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 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 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 ng0@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017 Christopher Allan Webber@*
49 Copyright @copyright{} 2017, 2018 Marius Bakke@*
50 Copyright @copyright{} 2017 Hartmut Goebel@*
51 Copyright @copyright{} 2017, 2019 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018, 2019 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@*
70 Permission is granted to copy, distribute and/or modify this document
71 under the terms of the GNU Free Documentation License, Version 1.3 or
72 any later version published by the Free Software Foundation; with no
73 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
74 copy of the license is included in the section entitled ``GNU Free
75 Documentation License''.
78 @dircategory System administration
80 * Guix: (guix). Manage installed software and system configuration.
81 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
82 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
83 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
84 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
85 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
88 @dircategory Software development
90 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
91 * guix build: (guix)Invoking guix build. Building packages.
92 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
96 @title GNU Guix Reference Manual
97 @subtitle Using the GNU Guix Functional Package Manager
98 @author The GNU Guix Developers
101 @vskip 0pt plus 1filll
102 Edition @value{EDITION} @*
110 @c *********************************************************************
114 This document describes GNU Guix version @value{VERSION}, a functional
115 package management tool written for the GNU system.
117 @c TRANSLATORS: You can replace the following paragraph with information on
118 @c how to join your own translation team and how to report issues with the
120 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
121 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
122 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
123 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
124 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
125 would like to translate it in your native language, consider joining the
126 @uref{https://translationproject.org/domain/guix-manual.html, Translation
130 * Introduction:: What is Guix about?
131 * Installation:: Installing Guix.
132 * System Installation:: Installing the whole operating system.
133 * Package Management:: Package installation, upgrade, etc.
134 * Development:: Guix-aided software development.
135 * Programming Interface:: Using Guix in Scheme.
136 * Utilities:: Package management commands.
137 * System Configuration:: Configuring the operating system.
138 * Documentation:: Browsing software user manuals.
139 * Installing Debugging Files:: Feeding the debugger.
140 * Security Updates:: Deploying security fixes quickly.
141 * Bootstrapping:: GNU/Linux built from scratch.
142 * Porting:: Targeting another platform or kernel.
143 * Contributing:: Your help needed!
145 * Acknowledgments:: Thanks!
146 * GNU Free Documentation License:: The license of this manual.
147 * Concept Index:: Concepts.
148 * Programming Index:: Data types, functions, and variables.
151 --- The Detailed Node Listing ---
155 * Managing Software the Guix Way:: What's special.
156 * GNU Distribution:: The packages and tools.
160 * Binary Installation:: Getting Guix running in no time!
161 * Requirements:: Software needed to build and run Guix.
162 * Running the Test Suite:: Testing Guix.
163 * Setting Up the Daemon:: Preparing the build daemon's environment.
164 * Invoking guix-daemon:: Running the build daemon.
165 * Application Setup:: Application-specific setup.
167 Setting Up the Daemon
169 * Build Environment Setup:: Preparing the isolated build environment.
170 * Daemon Offload Setup:: Offloading builds to remote machines.
171 * SELinux Support:: Using an SELinux policy for the daemon.
175 * Limitations:: What you can expect.
176 * Hardware Considerations:: Supported hardware.
177 * USB Stick and DVD Installation:: Preparing the installation medium.
178 * Preparing for Installation:: Networking, partitioning, etc.
179 * Guided Graphical Installation:: Easy graphical installation.
180 * Manual Installation:: Manual installation for wizards.
181 * After System Installation:: When installation succeeded.
182 * Installing Guix in a VM:: Guix System playground.
183 * Building the Installation Image:: How this comes to be.
187 * Keyboard Layout and Networking and Partitioning:: Initial setup.
188 * Proceeding with the Installation:: Installing.
192 * Features:: How Guix will make your life brighter.
193 * Invoking guix package:: Package installation, removal, etc.
194 * Substitutes:: Downloading pre-built binaries.
195 * Packages with Multiple Outputs:: Single source package, multiple outputs.
196 * Invoking guix gc:: Running the garbage collector.
197 * Invoking guix pull:: Fetching the latest Guix and distribution.
198 * Channels:: Customizing the package collection.
199 * Inferiors:: Interacting with another revision of Guix.
200 * Invoking guix describe:: Display information about your Guix revision.
201 * Invoking guix archive:: Exporting and importing store files.
205 * Official Substitute Server:: One particular source of substitutes.
206 * Substitute Server Authorization:: How to enable or disable substitutes.
207 * Substitute Authentication:: How Guix verifies substitutes.
208 * Proxy Settings:: How to get substitutes via proxy.
209 * Substitution Failure:: What happens when substitution fails.
210 * On Trusting Binaries:: How can you trust that binary blob?
214 * Invoking guix environment:: Setting up development environments.
215 * Invoking guix pack:: Creating software bundles.
217 Programming Interface
219 * Package Modules:: Packages from the programmer's viewpoint.
220 * Defining Packages:: Defining new packages.
221 * Build Systems:: Specifying how packages are built.
222 * The Store:: Manipulating the package store.
223 * Derivations:: Low-level interface to package derivations.
224 * The Store Monad:: Purely functional interface to the store.
225 * G-Expressions:: Manipulating build expressions.
226 * Invoking guix repl:: Fiddling with Guix interactively.
230 * package Reference:: The package data type.
231 * origin Reference:: The origin data type.
235 * Invoking guix build:: Building packages from the command line.
236 * Invoking guix edit:: Editing package definitions.
237 * Invoking guix download:: Downloading a file and printing its hash.
238 * Invoking guix hash:: Computing the cryptographic hash of a file.
239 * Invoking guix import:: Importing package definitions.
240 * Invoking guix refresh:: Updating package definitions.
241 * Invoking guix lint:: Finding errors in package definitions.
242 * Invoking guix size:: Profiling disk usage.
243 * Invoking guix graph:: Visualizing the graph of packages.
244 * Invoking guix publish:: Sharing substitutes.
245 * Invoking guix challenge:: Challenging substitute servers.
246 * Invoking guix copy:: Copying to and from a remote store.
247 * Invoking guix container:: Process isolation.
248 * Invoking guix weather:: Assessing substitute availability.
249 * Invoking guix processes:: Listing client processes.
251 Invoking @command{guix build}
253 * Common Build Options:: Build options for most commands.
254 * Package Transformation Options:: Creating variants of packages.
255 * Additional Build Options:: Options specific to 'guix build'.
256 * Debugging Build Failures:: Real life packaging experience.
260 * Using the Configuration System:: Customizing your GNU system.
261 * operating-system Reference:: Detail of operating-system declarations.
262 * File Systems:: Configuring file system mounts.
263 * Mapped Devices:: Block device extra processing.
264 * User Accounts:: Specifying user accounts.
265 * Keyboard Layout:: How the system interprets key strokes.
266 * Locales:: Language and cultural convention settings.
267 * Services:: Specifying system services.
268 * Setuid Programs:: Programs running with root privileges.
269 * X.509 Certificates:: Authenticating HTTPS servers.
270 * Name Service Switch:: Configuring libc's name service switch.
271 * Initial RAM Disk:: Linux-Libre bootstrapping.
272 * Bootloader Configuration:: Configuring the boot loader.
273 * Invoking guix system:: Instantiating a system configuration.
274 * Invoking guix deploy:: Deploying a system configuration to a remote host.
275 * Running Guix in a VM:: How to run Guix System in a virtual machine.
276 * Defining Services:: Adding new service definitions.
280 * Base Services:: Essential system services.
281 * Scheduled Job Execution:: The mcron service.
282 * Log Rotation:: The rottlog service.
283 * Networking Services:: Network setup, SSH daemon, etc.
284 * X Window:: Graphical display.
285 * Printing Services:: Local and remote printer support.
286 * Desktop Services:: D-Bus and desktop services.
287 * Sound Services:: ALSA and Pulseaudio services.
288 * Database Services:: SQL databases, key-value stores, etc.
289 * Mail Services:: IMAP, POP3, SMTP, and all that.
290 * Messaging Services:: Messaging services.
291 * Telephony Services:: Telephony services.
292 * Monitoring Services:: Monitoring services.
293 * Kerberos Services:: Kerberos services.
294 * Web Services:: Web servers.
295 * Certificate Services:: TLS certificates via Let's Encrypt.
296 * DNS Services:: DNS daemons.
297 * VPN Services:: VPN daemons.
298 * Network File System:: NFS related services.
299 * Continuous Integration:: The Cuirass service.
300 * Power Management Services:: Extending battery life.
301 * Audio Services:: The MPD.
302 * Virtualization Services:: Virtualization services.
303 * Version Control Services:: Providing remote access to Git repositories.
304 * Game Services:: Game servers.
305 * Miscellaneous Services:: Other services.
309 * Service Composition:: The model for composing services.
310 * Service Types and Services:: Types and services.
311 * Service Reference:: API reference.
312 * Shepherd Services:: A particular type of service.
317 @c *********************************************************************
319 @chapter Introduction
322 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
323 using the international phonetic alphabet (IPA).} is a package
324 management tool for and distribution of the GNU system.
325 Guix makes it easy for unprivileged
326 users to install, upgrade, or remove software packages, to roll back to a
327 previous package set, to build packages from source, and generally
328 assists with the creation and maintenance of software environments.
331 @cindex GuixSD, now Guix System
332 @cindex Guix System Distribution, now Guix System
333 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
334 complements the available tools without interference (@pxref{Installation}),
335 or you can use it as a standalone operating system distribution,
336 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
337 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
338 group everything under the ``Guix'' banner since, after all, Guix System is
339 readily available through the @command{guix system} command, even if you're
340 using a different distro underneath!}. @xref{GNU Distribution}.
343 * Managing Software the Guix Way:: What's special.
344 * GNU Distribution:: The packages and tools.
347 @node Managing Software the Guix Way
348 @section Managing Software the Guix Way
350 @cindex user interfaces
351 Guix provides a command-line package management interface
352 (@pxref{Package Management}), tools to help with software development
353 (@pxref{Development}), command-line utilities for more advanced usage,
354 (@pxref{Utilities}), as well as Scheme programming interfaces
355 (@pxref{Programming Interface}).
357 Its @dfn{build daemon} is responsible for building packages on behalf of
358 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
359 binaries from authorized sources (@pxref{Substitutes}).
361 @cindex extensibility of the distribution
362 @cindex customization, of packages
363 Guix includes package definitions for many GNU and non-GNU packages, all
364 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
365 user's computing freedom}. It is @emph{extensible}: users can write
366 their own package definitions (@pxref{Defining Packages}) and make them
367 available as independent package modules (@pxref{Package Modules}). It
368 is also @emph{customizable}: users can @emph{derive} specialized package
369 definitions from existing ones, including from the command line
370 (@pxref{Package Transformation Options}).
372 @cindex functional package management
374 Under the hood, Guix implements the @dfn{functional package management}
375 discipline pioneered by Nix (@pxref{Acknowledgments}).
376 In Guix, the package build and installation process is seen
377 as a @emph{function}, in the mathematical sense. That function takes inputs,
378 such as build scripts, a compiler, and libraries, and
379 returns an installed package. As a pure function, its result depends
380 solely on its inputs---for instance, it cannot refer to software or
381 scripts that were not explicitly passed as inputs. A build function
382 always produces the same result when passed a given set of inputs. It
383 cannot alter the environment of the running system in
384 any way; for instance, it cannot create, modify, or delete files outside
385 of its build and installation directories. This is achieved by running
386 build processes in isolated environments (or @dfn{containers}), where only their
387 explicit inputs are visible.
390 The result of package build functions is @dfn{cached} in the file
391 system, in a special directory called @dfn{the store} (@pxref{The
392 Store}). Each package is installed in a directory of its own in the
393 store---by default under @file{/gnu/store}. The directory name contains
394 a hash of all the inputs used to build that package; thus, changing an
395 input yields a different directory name.
397 This approach is the foundation for the salient features of Guix: support
398 for transactional package upgrade and rollback, per-user installation, and
399 garbage collection of packages (@pxref{Features}).
402 @node GNU Distribution
403 @section GNU Distribution
406 Guix comes with a distribution of the GNU system consisting entirely of
407 free software@footnote{The term ``free'' here refers to the
408 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
409 users of that software}.}. The
410 distribution can be installed on its own (@pxref{System Installation}),
411 but it is also possible to install Guix as a package manager on top of
412 an installed GNU/Linux system (@pxref{Installation}). When we need to
413 distinguish between the two, we refer to the standalone distribution as
416 The distribution provides core GNU packages such as GNU libc, GCC, and
417 Binutils, as well as many GNU and non-GNU applications. The complete
418 list of available packages can be browsed
419 @url{https://www.gnu.org/software/guix/packages,on-line} or by
420 running @command{guix package} (@pxref{Invoking guix package}):
423 guix package --list-available
426 Our goal is to provide a practical 100% free software distribution of
427 Linux-based and other variants of GNU, with a focus on the promotion and
428 tight integration of GNU components, and an emphasis on programs and
429 tools that help users exert that freedom.
431 Packages are currently available on the following platforms:
436 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
439 Intel 32-bit architecture (IA32), Linux-Libre kernel;
442 ARMv7-A architecture with hard float, Thumb-2 and NEON,
443 using the EABI hard-float application binary interface (ABI),
444 and Linux-Libre kernel.
447 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
450 little-endian 64-bit MIPS processors, specifically the Loongson series,
451 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
452 supported; in particular, the project's build farms no longer provide
453 substitutes for this architecture.
457 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
458 configuration and Guix takes care of instantiating the configuration in a
459 transactional, reproducible, and stateless fashion (@pxref{System
460 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
461 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
462 Manual}), the well-known GNU utilities and tool chain, as well as the
463 graphical environment or system services of your choice.
465 Guix System is available on all the above platforms except
466 @code{mips64el-linux}.
469 For information on porting to other architectures or kernels,
472 Building this distribution is a cooperative effort, and you are invited
473 to join! @xref{Contributing}, for information about how you can help.
476 @c *********************************************************************
478 @chapter Installation
480 @cindex installing Guix
483 We recommend the use of this
484 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
485 shell installer script} to install Guix on top of a running GNU/Linux system,
486 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
487 with the installation of the package manager, which can be done on top of a
488 running GNU/Linux system. If, instead, you want to install the complete GNU
489 operating system, @pxref{System Installation}.} The script automates the
490 download, installation, and initial configuration of Guix. It should be run
494 @cindex foreign distro
495 @cindex directories related to foreign distro
496 When installed on a foreign distro, GNU@tie{}Guix complements the available
497 tools without interference. Its data lives exclusively in two directories,
498 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
499 such as @file{/etc}, are left untouched.
501 Once installed, Guix can be updated by running @command{guix pull}
502 (@pxref{Invoking guix pull}).
504 If you prefer to perform the installation steps manually or want to tweak
505 them, you may find the following subsections useful. They describe the
506 software requirements of Guix, as well as how to install it manually and get
510 * Binary Installation:: Getting Guix running in no time!
511 * Requirements:: Software needed to build and run Guix.
512 * Running the Test Suite:: Testing Guix.
513 * Setting Up the Daemon:: Preparing the build daemon's environment.
514 * Invoking guix-daemon:: Running the build daemon.
515 * Application Setup:: Application-specific setup.
518 @node Binary Installation
519 @section Binary Installation
521 @cindex installing Guix from binaries
522 @cindex installer script
523 This section describes how to install Guix on an arbitrary system from a
524 self-contained tarball providing binaries for Guix and for all its
525 dependencies. This is often quicker than installing from source, which
526 is described in the next sections. The only requirement is to have
529 @c Note duplicated from the ``Installation'' node.
531 We recommend the use of this
532 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
533 shell installer script}. The script automates the download, installation, and
534 initial configuration steps described below. It should be run as the root
538 Installing goes along these lines:
542 @cindex downloading Guix binary
543 Download the binary tarball from
544 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz},
545 where @var{system} is @code{x86_64-linux} for an @code{x86_64} machine
546 already running the kernel Linux, and so on.
548 @c The following is somewhat duplicated in ``System Installation''.
549 Make sure to download the associated @file{.sig} file and to verify the
550 authenticity of the tarball against it, along these lines:
553 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
554 $ gpg --verify guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
557 If that command fails because you do not have the required public key,
558 then run this command to import it:
561 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
562 -qO - | gpg --import -
566 and rerun the @code{gpg --verify} command.
568 Take note that a warning like ``This key is not certified with a trusted
569 signature!'' is normal.
571 @c end authentication part
574 Now, you need to become the @code{root} user. Depending on your distribution,
575 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
579 # tar --warning=no-timestamp -xf \
580 /path/to/guix-binary-@value{VERSION}.@var{system}.tar.xz
581 # mv var/guix /var/ && mv gnu /
584 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
585 The latter contains a ready-to-use profile for @code{root} (see next
588 Do @emph{not} unpack the tarball on a working Guix system since that
589 would overwrite its own essential files.
591 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
592 not emit warnings about ``implausibly old time stamps'' (such
593 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
595 They stem from the fact that all the
596 files in the archive have their modification time set to zero (which
597 means January 1st, 1970.) This is done on purpose to make sure the
598 archive content is independent of its creation time, thus making it
602 Make the profile available under @file{~root/.config/guix/current}, which is
603 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
606 # mkdir -p ~root/.config/guix
607 # ln -sf /var/guix/profiles/per-user/root/current-guix \
608 ~root/.config/guix/current
611 Source @file{etc/profile} to augment @code{PATH} and other relevant
612 environment variables:
615 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
616 source $GUIX_PROFILE/etc/profile
620 Create the group and user accounts for build users as explained below
621 (@pxref{Build Environment Setup}).
624 Run the daemon, and set it to automatically start on boot.
626 If your host distro uses the systemd init system, this can be achieved
629 @c Versions of systemd that supported symlinked service files are not
630 @c yet widely deployed, so we should suggest that users copy the service
633 @c See this thread for more information:
634 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
637 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
639 # systemctl start guix-daemon && systemctl enable guix-daemon
642 If your host distro uses the Upstart init system:
645 # initctl reload-configuration
646 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
651 Otherwise, you can still start the daemon manually with:
654 # ~root/.config/guix/current/bin/guix-daemon \
655 --build-users-group=guixbuild
659 Make the @command{guix} command available to other users on the machine,
663 # mkdir -p /usr/local/bin
665 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
668 It is also a good idea to make the Info version of this manual available
672 # mkdir -p /usr/local/share/info
673 # cd /usr/local/share/info
674 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
678 That way, assuming @file{/usr/local/share/info} is in the search path,
679 running @command{info guix} will open this manual (@pxref{Other Info
680 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
684 @cindex substitutes, authorization thereof
685 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
686 (@pxref{Substitutes}), authorize them:
689 # guix archive --authorize < \
690 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
694 Each user may need to perform a few additional steps to make their Guix
695 environment ready for use, @pxref{Application Setup}.
698 Voilà, the installation is complete!
700 You can confirm that Guix is working by installing a sample package into
707 The binary installation tarball can be (re)produced and verified simply
708 by running the following command in the Guix source tree:
711 make guix-binary.@var{system}.tar.xz
715 ...@: which, in turn, runs:
718 guix pack -s @var{system} --localstatedir \
719 --profile-name=current-guix guix
722 @xref{Invoking guix pack}, for more info on this handy tool.
725 @section Requirements
727 This section lists requirements when building Guix from source. The
728 build procedure for Guix is the same as for other GNU software, and is
729 not covered here. Please see the files @file{README} and @file{INSTALL}
730 in the Guix source tree for additional details.
732 @cindex official website
733 GNU Guix is available for download from its website at
734 @url{https://www.gnu.org/software/guix/}.
736 GNU Guix depends on the following packages:
739 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 2.2.x;
740 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
743 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
744 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
745 Guile,, gnutls-guile, GnuTLS-Guile});
747 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
750 @c FIXME: Specify a version number once a release has been made.
751 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
753 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON} 3.x;
754 @item @url{https://zlib.net, zlib};
755 @item @url{https://www.gnu.org/software/make/, GNU Make}.
758 The following dependencies are optional:
762 @c Note: We need at least 0.10.2 for 'channel-send-eof'.
763 Support for build offloading (@pxref{Daemon Offload Setup}) and
764 @command{guix copy} (@pxref{Invoking guix copy}) depends on
765 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
766 version 0.10.2 or later.
769 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
770 substitutes can be used and @command{guix publish} can compress substitutes
774 When @url{http://www.bzip.org, libbz2} is available,
775 @command{guix-daemon} can use it to compress build logs.
778 Unless @code{--disable-daemon} was passed to @command{configure}, the
779 following packages are also needed:
782 @item @url{https://gnupg.org/, GNU libgcrypt};
783 @item @url{https://sqlite.org, SQLite 3};
784 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
788 @cindex state directory
789 When configuring Guix on a system that already has a Guix installation,
790 be sure to specify the same state directory as the existing installation
791 using the @code{--localstatedir} option of the @command{configure}
792 script (@pxref{Directory Variables, @code{localstatedir},, standards,
793 GNU Coding Standards}). The @command{configure} script protects against
794 unintended misconfiguration of @var{localstatedir} so you do not
795 inadvertently corrupt your store (@pxref{The Store}).
797 @cindex Nix, compatibility
798 When a working installation of @url{https://nixos.org/nix/, the Nix package
799 manager} is available, you
800 can instead configure Guix with @code{--disable-daemon}. In that case,
801 Nix replaces the three dependencies above.
803 Guix is compatible with Nix, so it is possible to share the same store
804 between both. To do so, you must pass @command{configure} not only the
805 same @code{--with-store-dir} value, but also the same
806 @code{--localstatedir} value. The latter is essential because it
807 specifies where the database that stores metadata about the store is
808 located, among other things. The default values for Nix are
809 @code{--with-store-dir=/nix/store} and @code{--localstatedir=/nix/var}.
810 Note that @code{--disable-daemon} is not required if
811 your goal is to share the store with Nix.
813 @node Running the Test Suite
814 @section Running the Test Suite
817 After a successful @command{configure} and @code{make} run, it is a good
818 idea to run the test suite. It can help catch issues with the setup or
819 environment, or bugs in Guix itself---and really, reporting test
820 failures is a good way to help improve the software. To run the test
827 Test cases can run in parallel: you can use the @code{-j} option of
828 GNU@tie{}make to speed things up. The first run may take a few minutes
829 on a recent machine; subsequent runs will be faster because the store
830 that is created for test purposes will already have various things in
833 It is also possible to run a subset of the tests by defining the
834 @code{TESTS} makefile variable as in this example:
837 make check TESTS="tests/store.scm tests/cpio.scm"
840 By default, tests results are displayed at a file level. In order to
841 see the details of every individual test cases, it is possible to define
842 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
845 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
848 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
849 @file{test-suite.log} file. Please specify the Guix version being used
850 as well as version numbers of the dependencies (@pxref{Requirements}) in
853 Guix also comes with a whole-system test suite that tests complete
854 Guix System instances. It can only run on systems where
855 Guix is already installed, using:
862 or, again, by defining @code{TESTS} to select a subset of tests to run:
865 make check-system TESTS="basic mcron"
868 These system tests are defined in the @code{(gnu tests @dots{})}
869 modules. They work by running the operating systems under test with
870 lightweight instrumentation in a virtual machine (VM). They can be
871 computationally intensive or rather cheap, depending on whether
872 substitutes are available for their dependencies (@pxref{Substitutes}).
873 Some of them require a lot of storage space to hold VM images.
875 Again in case of test failures, please send @email{bug-guix@@gnu.org}
878 @node Setting Up the Daemon
879 @section Setting Up the Daemon
882 Operations such as building a package or running the garbage collector
883 are all performed by a specialized process, the @dfn{build daemon}, on
884 behalf of clients. Only the daemon may access the store and its
885 associated database. Thus, any operation that manipulates the store
886 goes through the daemon. For instance, command-line tools such as
887 @command{guix package} and @command{guix build} communicate with the
888 daemon (@i{via} remote procedure calls) to instruct it what to do.
890 The following sections explain how to prepare the build daemon's
891 environment. See also @ref{Substitutes}, for information on how to allow
892 the daemon to download pre-built binaries.
895 * Build Environment Setup:: Preparing the isolated build environment.
896 * Daemon Offload Setup:: Offloading builds to remote machines.
897 * SELinux Support:: Using an SELinux policy for the daemon.
900 @node Build Environment Setup
901 @subsection Build Environment Setup
903 @cindex build environment
904 In a standard multi-user setup, Guix and its daemon---the
905 @command{guix-daemon} program---are installed by the system
906 administrator; @file{/gnu/store} is owned by @code{root} and
907 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
908 Guix tools to build packages or otherwise access the store, and the
909 daemon will do it on their behalf, ensuring that the store is kept in a
910 consistent state, and allowing built packages to be shared among users.
913 When @command{guix-daemon} runs as @code{root}, you may not want package
914 build processes themselves to run as @code{root} too, for obvious
915 security reasons. To avoid that, a special pool of @dfn{build users}
916 should be created for use by build processes started by the daemon.
917 These build users need not have a shell and a home directory: they will
918 just be used when the daemon drops @code{root} privileges in build
919 processes. Having several such users allows the daemon to launch
920 distinct build processes under separate UIDs, which guarantees that they
921 do not interfere with each other---an essential feature since builds are
922 regarded as pure functions (@pxref{Introduction}).
924 On a GNU/Linux system, a build user pool may be created like this (using
925 Bash syntax and the @code{shadow} commands):
927 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
928 @c for why `-G' is needed.
930 # groupadd --system guixbuild
931 # for i in `seq -w 1 10`;
933 useradd -g guixbuild -G guixbuild \
934 -d /var/empty -s `which nologin` \
935 -c "Guix build user $i" --system \
941 The number of build users determines how many build jobs may run in
942 parallel, as specified by the @option{--max-jobs} option
943 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
944 @command{guix system vm} and related commands, you may need to add the
945 build users to the @code{kvm} group so they can access @file{/dev/kvm},
946 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
947 (@pxref{Invoking guix system}).
949 The @code{guix-daemon} program may then be run as @code{root} with the
950 following command@footnote{If your machine uses the systemd init system,
951 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
952 file in @file{/etc/systemd/system} will ensure that
953 @command{guix-daemon} is automatically started. Similarly, if your
954 machine uses the Upstart init system, drop the
955 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
956 file in @file{/etc/init}.}:
959 # guix-daemon --build-users-group=guixbuild
964 This way, the daemon starts build processes in a chroot, under one of
965 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
966 environment contains nothing but:
968 @c Keep this list in sync with libstore/build.cc! -----------------------
971 a minimal @code{/dev} directory, created mostly independently from the
972 host @code{/dev}@footnote{``Mostly'', because while the set of files
973 that appear in the chroot's @code{/dev} is fixed, most of these files
974 can only be created if the host has them.};
977 the @code{/proc} directory; it only shows the processes of the container
978 since a separate PID name space is used;
981 @file{/etc/passwd} with an entry for the current user and an entry for
985 @file{/etc/group} with an entry for the user's group;
988 @file{/etc/hosts} with an entry that maps @code{localhost} to
992 a writable @file{/tmp} directory.
995 You can influence the directory where the daemon stores build trees
996 @i{via} the @code{TMPDIR} environment variable. However, the build tree
997 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
998 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
999 This way, the value of @code{TMPDIR} does not leak inside build
1000 environments, which avoids discrepancies in cases where build processes
1001 capture the name of their build tree.
1004 The daemon also honors the @code{http_proxy} environment variable for
1005 HTTP downloads it performs, be it for fixed-output derivations
1006 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1008 If you are installing Guix as an unprivileged user, it is still possible
1009 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1010 However, build processes will not be isolated from one another, and not
1011 from the rest of the system. Thus, build processes may interfere with
1012 each other, and may access programs, libraries, and other files
1013 available on the system---making it much harder to view them as
1014 @emph{pure} functions.
1017 @node Daemon Offload Setup
1018 @subsection Using the Offload Facility
1022 When desired, the build daemon can @dfn{offload} derivation builds to
1023 other machines running Guix, using the @code{offload} @dfn{build
1024 hook}@footnote{This feature is available only when
1025 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1026 present.}. When that
1027 feature is enabled, a list of user-specified build machines is read from
1028 @file{/etc/guix/machines.scm}; every time a build is requested, for
1029 instance via @code{guix build}, the daemon attempts to offload it to one
1030 of the machines that satisfy the constraints of the derivation, in
1031 particular its system type---e.g., @file{x86_64-linux}. Missing
1032 prerequisites for the build are copied over SSH to the target machine,
1033 which then proceeds with the build; upon success the output(s) of the
1034 build are copied back to the initial machine.
1036 The @file{/etc/guix/machines.scm} file typically looks like this:
1039 (list (build-machine
1040 (name "eightysix.example.org")
1041 (system "x86_64-linux")
1042 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1044 (speed 2.)) ;incredibly fast!
1047 (name "meeps.example.org")
1048 (system "mips64el-linux")
1049 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1052 (string-append (getenv "HOME")
1053 "/.ssh/identity-for-guix"))))
1057 In the example above we specify a list of two build machines, one for
1058 the @code{x86_64} architecture and one for the @code{mips64el}
1061 In fact, this file is---not surprisingly!---a Scheme file that is
1062 evaluated when the @code{offload} hook is started. Its return value
1063 must be a list of @code{build-machine} objects. While this example
1064 shows a fixed list of build machines, one could imagine, say, using
1065 DNS-SD to return a list of potential build machines discovered in the
1066 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1067 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1070 @deftp {Data Type} build-machine
1071 This data type represents build machines to which the daemon may offload
1072 builds. The important fields are:
1077 The host name of the remote machine.
1080 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1083 The user account to use when connecting to the remote machine over SSH.
1084 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1085 allow non-interactive logins.
1088 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1089 This is used to authenticate the machine when we connect to it. It is a
1090 long string that looks like this:
1093 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1096 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1097 key can be found in a file such as
1098 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1100 If the machine is running the SSH daemon of GNU@tie{}lsh,
1101 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1102 similar file. It can be converted to the OpenSSH format using
1103 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1106 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1107 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1112 A number of optional fields may be specified:
1116 @item @code{port} (default: @code{22})
1117 Port number of SSH server on the machine.
1119 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1120 The SSH private key file to use when connecting to the machine, in
1121 OpenSSH format. This key must not be protected with a passphrase.
1123 Note that the default value is the private key @emph{of the root
1124 account}. Make sure it exists if you use the default.
1126 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1127 @itemx @code{compression-level} (default: @code{3})
1128 The SSH-level compression methods and compression level requested.
1130 Note that offloading relies on SSH compression to reduce bandwidth usage
1131 when transferring files to and from build machines.
1133 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1134 File name of the Unix-domain socket @command{guix-daemon} is listening
1137 @item @code{parallel-builds} (default: @code{1})
1138 The number of builds that may run in parallel on the machine.
1140 @item @code{speed} (default: @code{1.0})
1141 A ``relative speed factor''. The offload scheduler will tend to prefer
1142 machines with a higher speed factor.
1144 @item @code{features} (default: @code{'()})
1145 A list of strings denoting specific features supported by the machine.
1146 An example is @code{"kvm"} for machines that have the KVM Linux modules
1147 and corresponding hardware support. Derivations can request features by
1148 name, and they will be scheduled on matching build machines.
1153 The @command{guix} command must be in the search path on the build
1154 machines. You can check whether this is the case by running:
1157 ssh build-machine guix repl --version
1160 There is one last thing to do once @file{machines.scm} is in place. As
1161 explained above, when offloading, files are transferred back and forth
1162 between the machine stores. For this to work, you first need to
1163 generate a key pair on each machine to allow the daemon to export signed
1164 archives of files from the store (@pxref{Invoking guix archive}):
1167 # guix archive --generate-key
1171 Each build machine must authorize the key of the master machine so that
1172 it accepts store items it receives from the master:
1175 # guix archive --authorize < master-public-key.txt
1179 Likewise, the master machine must authorize the key of each build machine.
1181 All the fuss with keys is here to express pairwise mutual trust
1182 relations between the master and the build machines. Concretely, when
1183 the master receives files from a build machine (and @i{vice versa}), its
1184 build daemon can make sure they are genuine, have not been tampered
1185 with, and that they are signed by an authorized key.
1187 @cindex offload test
1188 To test whether your setup is operational, run this command on the
1195 This will attempt to connect to each of the build machines specified in
1196 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1197 available on each machine, attempt to export to the machine and import
1198 from it, and report any error in the process.
1200 If you want to test a different machine file, just specify it on the
1204 # guix offload test machines-qualif.scm
1207 Last, you can test the subset of the machines whose name matches a
1208 regular expression like this:
1211 # guix offload test machines.scm '\.gnu\.org$'
1214 @cindex offload status
1215 To display the current load of all build hosts, run this command on the
1219 # guix offload status
1223 @node SELinux Support
1224 @subsection SELinux Support
1226 @cindex SELinux, daemon policy
1227 @cindex mandatory access control, SELinux
1228 @cindex security, guix-daemon
1229 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1230 can be installed on a system where SELinux is enabled, in order to label
1231 Guix files and to specify the expected behavior of the daemon. Since
1232 Guix System does not provide an SELinux base policy, the daemon policy cannot
1233 be used on Guix System.
1235 @subsubsection Installing the SELinux policy
1236 @cindex SELinux, policy installation
1237 To install the policy run this command as root:
1240 semodule -i etc/guix-daemon.cil
1243 Then relabel the file system with @code{restorecon} or by a different
1244 mechanism provided by your system.
1246 Once the policy is installed, the file system has been relabeled, and
1247 the daemon has been restarted, it should be running in the
1248 @code{guix_daemon_t} context. You can confirm this with the following
1252 ps -Zax | grep guix-daemon
1255 Monitor the SELinux log files as you run a command like @code{guix build
1256 hello} to convince yourself that SELinux permits all necessary
1259 @subsubsection Limitations
1260 @cindex SELinux, limitations
1262 This policy is not perfect. Here is a list of limitations or quirks
1263 that should be considered when deploying the provided SELinux policy for
1268 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1269 operations involve contexts that have anything to do with
1270 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1271 but it would be preferrable to define socket rules for only this label.
1274 @code{guix gc} cannot access arbitrary links to profiles. By design,
1275 the file label of the destination of a symlink is independent of the
1276 file label of the link itself. Although all profiles under
1277 $localstatedir are labelled, the links to these profiles inherit the
1278 label of the directory they are in. For links in the user’s home
1279 directory this will be @code{user_home_t}. But for links from the root
1280 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1281 directory, etc, this won’t work. @code{guix gc} would be prevented from
1282 reading and following these links.
1285 The daemon’s feature to listen for TCP connections might no longer work.
1286 This might require extra rules, because SELinux treats network sockets
1287 differently from files.
1290 Currently all files with a name matching the regular expression
1291 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1292 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1293 that name in any profile would be permitted to run in the
1294 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1295 build a package that provides this executable and convince a user to
1296 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1297 At that point SELinux could not prevent it from accessing files that are
1298 allowed for processes in that domain.
1300 We could generate a much more restrictive policy at installation time,
1301 so that only the @emph{exact} file name of the currently installed
1302 @code{guix-daemon} executable would be labelled with
1303 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1304 The downside is that root would have to install or upgrade the policy at
1305 installation time whenever the Guix package that provides the
1306 effectively running @code{guix-daemon} executable is upgraded.
1309 @node Invoking guix-daemon
1310 @section Invoking @command{guix-daemon}
1312 The @command{guix-daemon} program implements all the functionality to
1313 access the store. This includes launching build processes, running the
1314 garbage collector, querying the availability of a build result, etc. It
1315 is normally run as @code{root} like this:
1318 # guix-daemon --build-users-group=guixbuild
1322 For details on how to set it up, @pxref{Setting Up the Daemon}.
1325 @cindex container, build environment
1326 @cindex build environment
1327 @cindex reproducible builds
1328 By default, @command{guix-daemon} launches build processes under
1329 different UIDs, taken from the build group specified with
1330 @code{--build-users-group}. In addition, each build process is run in a
1331 chroot environment that only contains the subset of the store that the
1332 build process depends on, as specified by its derivation
1333 (@pxref{Programming Interface, derivation}), plus a set of specific
1334 system directories. By default, the latter contains @file{/dev} and
1335 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1336 @dfn{container}: in addition to having its own file system tree, it has
1337 a separate mount name space, its own PID name space, network name space,
1338 etc. This helps achieve reproducible builds (@pxref{Features}).
1340 When the daemon performs a build on behalf of the user, it creates a
1341 build directory under @file{/tmp} or under the directory specified by
1342 its @code{TMPDIR} environment variable. This directory is shared with
1343 the container for the duration of the build, though within the container,
1344 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1346 The build directory is automatically deleted upon completion, unless the
1347 build failed and the client specified @option{--keep-failed}
1348 (@pxref{Invoking guix build, @option{--keep-failed}}).
1350 The daemon listens for connections and spawns one sub-process for each session
1351 started by a client (one of the @command{guix} sub-commands.) The
1352 @command{guix processes} command allows you to get an overview of the activity
1353 on your system by viewing each of the active sessions and clients.
1354 @xref{Invoking guix processes}, for more information.
1356 The following command-line options are supported:
1359 @item --build-users-group=@var{group}
1360 Take users from @var{group} to run build processes (@pxref{Setting Up
1361 the Daemon, build users}).
1363 @item --no-substitutes
1365 Do not use substitutes for build products. That is, always build things
1366 locally instead of allowing downloads of pre-built binaries
1367 (@pxref{Substitutes}).
1369 When the daemon runs with @code{--no-substitutes}, clients can still
1370 explicitly enable substitution @i{via} the @code{set-build-options}
1371 remote procedure call (@pxref{The Store}).
1373 @item --substitute-urls=@var{urls}
1374 @anchor{daemon-substitute-urls}
1375 Consider @var{urls} the default whitespace-separated list of substitute
1376 source URLs. When this option is omitted,
1377 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1379 This means that substitutes may be downloaded from @var{urls}, as long
1380 as they are signed by a trusted signature (@pxref{Substitutes}).
1383 @item --no-build-hook
1384 Do not use the @dfn{build hook}.
1386 The build hook is a helper program that the daemon can start and to
1387 which it submits build requests. This mechanism is used to offload
1388 builds to other machines (@pxref{Daemon Offload Setup}).
1390 @item --cache-failures
1391 Cache build failures. By default, only successful builds are cached.
1393 When this option is used, @command{guix gc --list-failures} can be used
1394 to query the set of store items marked as failed; @command{guix gc
1395 --clear-failures} removes store items from the set of cached failures.
1396 @xref{Invoking guix gc}.
1398 @item --cores=@var{n}
1400 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1403 The default value is @code{0}, but it may be overridden by clients, such
1404 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1407 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1408 in the build process, which can then use it to exploit internal
1409 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1411 @item --max-jobs=@var{n}
1413 Allow at most @var{n} build jobs in parallel. The default value is
1414 @code{1}. Setting it to @code{0} means that no builds will be performed
1415 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1416 Setup}), or simply fail.
1418 @item --max-silent-time=@var{seconds}
1419 When the build or substitution process remains silent for more than
1420 @var{seconds}, terminate it and report a build failure.
1422 The default value is @code{0}, which disables the timeout.
1424 The value specified here can be overridden by clients (@pxref{Common
1425 Build Options, @code{--max-silent-time}}).
1427 @item --timeout=@var{seconds}
1428 Likewise, when the build or substitution process lasts for more than
1429 @var{seconds}, terminate it and report a build failure.
1431 The default value is @code{0}, which disables the timeout.
1433 The value specified here can be overridden by clients (@pxref{Common
1434 Build Options, @code{--timeout}}).
1436 @item --rounds=@var{N}
1437 Build each derivation @var{n} times in a row, and raise an error if
1438 consecutive build results are not bit-for-bit identical. Note that this
1439 setting can be overridden by clients such as @command{guix build}
1440 (@pxref{Invoking guix build}).
1442 When used in conjunction with @option{--keep-failed}, the differing
1443 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1444 This makes it easy to look for differences between the two results.
1447 Produce debugging output.
1449 This is useful to debug daemon start-up issues, but then it may be
1450 overridden by clients, for example the @code{--verbosity} option of
1451 @command{guix build} (@pxref{Invoking guix build}).
1453 @item --chroot-directory=@var{dir}
1454 Add @var{dir} to the build chroot.
1456 Doing this may change the result of build processes---for instance if
1457 they use optional dependencies found in @var{dir} when it is available,
1458 and not otherwise. For that reason, it is not recommended to do so.
1459 Instead, make sure that each derivation declares all the inputs that it
1462 @item --disable-chroot
1463 Disable chroot builds.
1465 Using this option is not recommended since, again, it would allow build
1466 processes to gain access to undeclared dependencies. It is necessary,
1467 though, when @command{guix-daemon} is running under an unprivileged user
1470 @item --log-compression=@var{type}
1471 Compress build logs according to @var{type}, one of @code{gzip},
1472 @code{bzip2}, or @code{none}.
1474 Unless @code{--lose-logs} is used, all the build logs are kept in the
1475 @var{localstatedir}. To save space, the daemon automatically compresses
1476 them with bzip2 by default.
1478 @item --disable-deduplication
1479 @cindex deduplication
1480 Disable automatic file ``deduplication'' in the store.
1482 By default, files added to the store are automatically ``deduplicated'':
1483 if a newly added file is identical to another one found in the store,
1484 the daemon makes the new file a hard link to the other file. This can
1485 noticeably reduce disk usage, at the expense of slightly increased
1486 input/output load at the end of a build process. This option disables
1489 @item --gc-keep-outputs[=yes|no]
1490 Tell whether the garbage collector (GC) must keep outputs of live
1494 @cindex garbage collector roots
1495 When set to ``yes'', the GC will keep the outputs of any live derivation
1496 available in the store---the @code{.drv} files. The default is ``no'',
1497 meaning that derivation outputs are kept only if they are reachable from a GC
1498 root. @xref{Invoking guix gc}, for more on GC roots.
1500 @item --gc-keep-derivations[=yes|no]
1501 Tell whether the garbage collector (GC) must keep derivations
1502 corresponding to live outputs.
1504 When set to ``yes'', as is the case by default, the GC keeps
1505 derivations---i.e., @code{.drv} files---as long as at least one of their
1506 outputs is live. This allows users to keep track of the origins of
1507 items in their store. Setting it to ``no'' saves a bit of disk space.
1509 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1510 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1511 ``yes'' causes liveness to flow from derivations to outputs. When both are
1512 set to ``yes'', the effect is to keep all the build prerequisites (the
1513 sources, compiler, libraries, and other build-time tools) of live objects in
1514 the store, regardless of whether these prerequisites are reachable from a GC
1515 root. This is convenient for developers since it saves rebuilds or downloads.
1517 @item --impersonate-linux-2.6
1518 On Linux-based systems, impersonate Linux 2.6. This means that the
1519 kernel's @code{uname} system call will report 2.6 as the release number.
1521 This might be helpful to build programs that (usually wrongfully) depend
1522 on the kernel version number.
1525 Do not keep build logs. By default they are kept under
1526 @code{@var{localstatedir}/guix/log}.
1528 @item --system=@var{system}
1529 Assume @var{system} as the current system type. By default it is the
1530 architecture/kernel pair found at configure time, such as
1531 @code{x86_64-linux}.
1533 @item --listen=@var{endpoint}
1534 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1535 as the file name of a Unix-domain socket if it starts with
1536 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1537 host name or host name and port to listen to. Here are a few examples:
1540 @item --listen=/gnu/var/daemon
1541 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1542 creating it if needed.
1544 @item --listen=localhost
1545 @cindex daemon, remote access
1546 @cindex remote access to the daemon
1547 @cindex daemon, cluster setup
1548 @cindex clusters, daemon setup
1549 Listen for TCP connections on the network interface corresponding to
1550 @code{localhost}, on port 44146.
1552 @item --listen=128.0.0.42:1234
1553 Listen for TCP connections on the network interface corresponding to
1554 @code{128.0.0.42}, on port 1234.
1557 This option can be repeated multiple times, in which case
1558 @command{guix-daemon} accepts connections on all the specified
1559 endpoints. Users can tell client commands what endpoint to connect to
1560 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1561 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1564 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1565 @code{--listen=@var{host}} is suitable on local networks, such as
1566 clusters, where only trusted nodes may connect to the build daemon. In
1567 other cases where remote access to the daemon is needed, we recommend
1568 using Unix-domain sockets along with SSH.
1571 When @code{--listen} is omitted, @command{guix-daemon} listens for
1572 connections on the Unix-domain socket located at
1573 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1577 @node Application Setup
1578 @section Application Setup
1580 @cindex foreign distro
1581 When using Guix on top of GNU/Linux distribution other than Guix System---a
1582 so-called @dfn{foreign distro}---a few additional steps are needed to
1583 get everything in place. Here are some of them.
1587 @anchor{locales-and-locpath}
1588 @cindex locales, when not on Guix System
1590 @vindex GUIX_LOCPATH
1591 Packages installed @i{via} Guix will not use the locale data of the
1592 host system. Instead, you must first install one of the locale packages
1593 available with Guix and then define the @code{GUIX_LOCPATH} environment
1597 $ guix install glibc-locales
1598 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1601 Note that the @code{glibc-locales} package contains data for all the
1602 locales supported by the GNU@tie{}libc and weighs in at around
1603 110@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1604 limited to a few UTF-8 locales.
1606 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1607 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1608 Manual}). There are two important differences though:
1612 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1613 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1614 to make sure the programs of the foreign distro will not end up loading
1615 incompatible locale data.
1618 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1619 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1620 should your Guix profile contain a mixture of programs linked against
1621 different libc version, each libc version will only try to load locale
1622 data in the right format.
1625 This is important because the locale data format used by different libc
1626 versions may be incompatible.
1628 @subsection Name Service Switch
1630 @cindex name service switch, glibc
1631 @cindex NSS (name service switch), glibc
1632 @cindex nscd (name service caching daemon)
1633 @cindex name service caching daemon (nscd)
1634 When using Guix on a foreign distro, we @emph{strongly recommend} that
1635 the system run the GNU C library's @dfn{name service cache daemon},
1636 @command{nscd}, which should be listening on the
1637 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1638 installed with Guix may fail to look up host names or user accounts, or
1639 may even crash. The next paragraphs explain why.
1641 @cindex @file{nsswitch.conf}
1642 The GNU C library implements a @dfn{name service switch} (NSS), which is
1643 an extensible mechanism for ``name lookups'' in general: host name
1644 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1645 The GNU C Library Reference Manual}).
1647 @cindex Network information service (NIS)
1648 @cindex NIS (Network information service)
1649 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1650 lookup implementations: for example, the @code{nss-mdns} plugin allow
1651 resolution of @code{.local} host names, the @code{nis} plugin allows
1652 user account lookup using the Network information service (NIS), and so
1653 on. These extra ``lookup services'' are configured system-wide in
1654 @file{/etc/nsswitch.conf}, and all the programs running on the system
1655 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1658 When they perform a name lookup---for instance by calling the
1659 @code{getaddrinfo} function in C---applications first try to connect to
1660 the nscd; on success, nscd performs name lookups on their behalf. If
1661 the nscd is not running, then they perform the name lookup by
1662 themselves, by loading the name lookup services into their own address
1663 space and running it. These name lookup services---the
1664 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1665 the host system's C library, rather than from the C library the
1666 application is linked against (the C library coming from Guix).
1668 And this is where the problem is: if your application is linked against
1669 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1670 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1671 likely crash or have its name lookups fail unexpectedly.
1673 Running @command{nscd} on the system, among other advantages, eliminates
1674 this binary incompatibility problem because those @code{libnss_*.so}
1675 files are loaded in the @command{nscd} process, not in applications
1678 @subsection X11 Fonts
1681 The majority of graphical applications use Fontconfig to locate and
1682 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1683 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1684 by default. Thus, to allow graphical applications installed with Guix
1685 to display fonts, you have to install fonts with Guix as well.
1686 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1687 @code{font-gnu-freefont-ttf}.
1689 To display text written in Chinese languages, Japanese, or Korean in
1690 graphical applications, consider installing
1691 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1692 has multiple outputs, one per language family (@pxref{Packages with
1693 Multiple Outputs}). For instance, the following command installs fonts
1694 for Chinese languages:
1697 guix install font-adobe-source-han-sans:cn
1700 @cindex @code{xterm}
1701 Older programs such as @command{xterm} do not use Fontconfig and instead
1702 rely on server-side font rendering. Such programs require to specify a
1703 full name of a font using XLFD (X Logical Font Description), like this:
1706 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1709 To be able to use such full names for the TrueType fonts installed in
1710 your Guix profile, you need to extend the font path of the X server:
1712 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1713 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1715 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1718 @cindex @code{xlsfonts}
1719 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1720 to make sure your TrueType fonts are listed there.
1722 @cindex @code{fc-cache}
1724 After installing fonts you may have to refresh the font cache to use
1725 them in applications. The same applies when applications installed via
1726 Guix do not seem to find fonts. To force rebuilding of the font cache
1727 run @code{fc-cache -f}. The @code{fc-cache} command is provided by the
1728 @code{fontconfig} package.
1730 @subsection X.509 Certificates
1732 @cindex @code{nss-certs}
1733 The @code{nss-certs} package provides X.509 certificates, which allow
1734 programs to authenticate Web servers accessed over HTTPS.
1736 When using Guix on a foreign distro, you can install this package and
1737 define the relevant environment variables so that packages know where to
1738 look for certificates. @xref{X.509 Certificates}, for detailed
1741 @subsection Emacs Packages
1743 @cindex @code{emacs}
1744 When you install Emacs packages with Guix, the elisp files may be placed
1745 either in @file{$HOME/.guix-profile/share/emacs/site-lisp/} or in
1747 @file{$HOME/.guix-profile/share/emacs/site-lisp/guix.d/}. The latter
1748 directory exists because potentially there may exist thousands of Emacs
1749 packages and storing all their files in a single directory may not be
1750 reliable (because of name conflicts). So we think using a separate
1751 directory for each package is a good idea. It is very similar to how
1752 the Emacs package system organizes the file structure (@pxref{Package
1753 Files,,, emacs, The GNU Emacs Manual}).
1755 By default, Emacs (installed with Guix) ``knows'' where these packages
1756 are placed, so you do not need to perform any configuration. If, for
1757 some reason, you want to avoid auto-loading Emacs packages installed
1758 with Guix, you can do so by running Emacs with @code{--no-site-file}
1759 option (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1761 @subsection The GCC toolchain
1766 Guix offers individual compiler packages such as @code{gcc} but if you
1767 are in need of a complete toolchain for compiling and linking source
1768 code what you really want is the @code{gcc-toolchain} package. This
1769 package provides a complete GCC toolchain for C/C++ development,
1770 including GCC itself, the GNU C Library (headers and binaries, plus
1771 debugging symbols in the @code{debug} output), Binutils, and a linker
1774 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
1775 passed to the linker, add corresponding @code{-rpath} arguments, and
1776 invoke the actual linker with this new set of arguments. You can instruct the
1777 wrapper to refuse to link against libraries not in the store by setting the
1778 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
1782 @c *********************************************************************
1783 @node System Installation
1784 @chapter System Installation
1786 @cindex installing Guix System
1787 @cindex Guix System, installation
1788 This section explains how to install Guix System
1789 on a machine. Guix, as a package manager, can
1790 also be installed on top of a running GNU/Linux system,
1791 @pxref{Installation}.
1795 @c This paragraph is for people reading this from tty2 of the
1796 @c installation image.
1797 You are reading this documentation with an Info reader. For details on
1798 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1799 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1800 Info}. Hit @kbd{l} afterwards to come back here.
1802 Alternately, run @command{info info} in another tty to keep the manual
1808 * Limitations:: What you can expect.
1809 * Hardware Considerations:: Supported hardware.
1810 * USB Stick and DVD Installation:: Preparing the installation medium.
1811 * Preparing for Installation:: Networking, partitioning, etc.
1812 * Guided Graphical Installation:: Easy graphical installation.
1813 * Manual Installation:: Manual installation for wizards.
1814 * After System Installation:: When installation succeeded.
1815 * Installing Guix in a VM:: Guix System playground.
1816 * Building the Installation Image:: How this comes to be.
1820 @section Limitations
1822 We consider Guix System to be ready for a wide range of ``desktop'' and server
1823 use cases. The reliability guarantees it provides---transactional upgrades
1824 and rollbacks, reproducibility---make it a solid foundation.
1826 Nevertheless, before you proceed with the installation, be aware of the
1827 following noteworthy limitations applicable to version @value{VERSION}:
1831 Support for the Logical Volume Manager (LVM) is missing.
1834 More and more system services are provided (@pxref{Services}), but some
1838 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1839 as well as a number of X11 window managers. However, KDE is currently
1843 More than a disclaimer, this is an invitation to report issues (and success
1844 stories!), and to join us in improving it. @xref{Contributing}, for more
1848 @node Hardware Considerations
1849 @section Hardware Considerations
1851 @cindex hardware support on Guix System
1852 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1853 builds around the kernel Linux-libre, which means that only hardware for
1854 which free software drivers and firmware exist is supported. Nowadays,
1855 a wide range of off-the-shelf hardware is supported on
1856 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1857 Ethernet controllers. Unfortunately, there are still areas where
1858 hardware vendors deny users control over their own computing, and such
1859 hardware is not supported on Guix System.
1861 @cindex WiFi, hardware support
1862 One of the main areas where free drivers or firmware are lacking is WiFi
1863 devices. WiFi devices known to work include those using Atheros chips
1864 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1865 driver, and those using Broadcom/AirForce chips (BCM43xx with
1866 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1867 Linux-libre driver. Free firmware exists for both and is available
1868 out-of-the-box on Guix System, as part of @code{%base-firmware}
1869 (@pxref{operating-system Reference, @code{firmware}}).
1871 @cindex RYF, Respects Your Freedom
1872 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1873 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1874 certification program for hardware products that respect your freedom
1875 and your privacy and ensure that you have control over your device. We
1876 encourage you to check the list of RYF-certified devices.
1878 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1879 web site. It contains a catalog of hardware devices with information
1880 about their support in GNU/Linux.
1883 @node USB Stick and DVD Installation
1884 @section USB Stick and DVD Installation
1886 An ISO-9660 installation image that can be written to a USB stick or
1887 burnt to a DVD can be downloaded from
1888 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1889 where @var{system} is one of:
1893 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1896 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1899 @c start duplication of authentication part from ``Binary Installation''
1900 Make sure to download the associated @file{.sig} file and to verify the
1901 authenticity of the image against it, along these lines:
1904 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1905 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1908 If that command fails because you do not have the required public key,
1909 then run this command to import it:
1912 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1913 -qO - | gpg --import -
1917 and rerun the @code{gpg --verify} command.
1919 Take note that a warning like ``This key is not certified with a trusted
1920 signature!'' is normal.
1924 This image contains the tools necessary for an installation.
1925 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1927 @unnumberedsubsec Copying to a USB Stick
1929 To copy the image to a USB stick, follow these steps:
1933 Decompress the image using the @command{xz} command:
1936 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1940 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1941 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1942 copy the image with:
1945 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1949 Access to @file{/dev/sdX} usually requires root privileges.
1952 @unnumberedsubsec Burning on a DVD
1954 To copy the image to a DVD, follow these steps:
1958 Decompress the image using the @command{xz} command:
1961 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1965 Insert a blank DVD into your machine, and determine
1966 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
1967 copy the image with:
1970 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
1973 Access to @file{/dev/srX} usually requires root privileges.
1976 @unnumberedsubsec Booting
1978 Once this is done, you should be able to reboot the system and boot from
1979 the USB stick or DVD. The latter usually requires you to get in the
1980 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
1982 @xref{Installing Guix in a VM}, if, instead, you would like to install
1983 Guix System in a virtual machine (VM).
1986 @node Preparing for Installation
1987 @section Preparing for Installation
1989 Once you have booted, you can use the guided graphical installer, which makes
1990 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
1991 if you are already familiar with GNU/Linux and if you want more control than
1992 what the graphical installer provides, you can choose the ``manual''
1993 installation process (@pxref{Manual Installation}).
1995 The graphical installer is available on TTY1. You can obtain root shells on
1996 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
1997 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
1998 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
1999 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2000 which allows you to select text with the left mouse button and to paste it
2001 with the middle button.
2004 Installation requires access to the Internet so that any missing
2005 dependencies of your system configuration can be downloaded. See the
2006 ``Networking'' section below.
2009 @node Guided Graphical Installation
2010 @section Guided Graphical Installation
2012 The graphical installer is a text-based user interface. It will guide you,
2013 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2015 The first dialog boxes allow you to set up the system as you use it during the
2016 installation: you can choose the language, keyboard layout, and set up
2017 networking, which will be used during the installation. The image below shows
2018 the networking dialog.
2020 @image{images/installer-network,5in,, networking setup with the graphical installer}
2022 Later steps allow you to partition your hard disk, as shown in the image
2023 below, to choose whether or not to use encrypted file systems, to enter the
2024 host name and root password, and to create an additional account, among other
2027 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2029 Note that, at any time, the installer allows you to exit the current
2030 installation step and resume at a previous step, as show in the image below.
2032 @image{images/installer-resume,5in,, resuming the installation process}
2034 Once you're done, the installer produces an operating system configuration and
2035 displays it (@pxref{Using the Configuration System}). At that point you can
2036 hit ``OK'' and installation will proceed. On success, you can reboot into the
2037 new system and enjoy. @xref{After System Installation}, for what's next!
2040 @node Manual Installation
2041 @section Manual Installation
2043 This section describes how you would ``manually'' install GNU@tie{}Guix System
2044 on your machine. This option requires familiarity with GNU/Linux, with the
2045 shell, and with common administration tools. If you think this is not for
2046 you, consider using the guided graphical installer (@pxref{Guided Graphical
2049 The installation system provides root shells on TTYs 3 to 6; press
2050 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2051 many common tools needed to install the system. But it is also a full-blown
2052 Guix System, which means that you can install additional packages, should you
2053 need it, using @command{guix package} (@pxref{Invoking guix package}).
2056 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2057 * Proceeding with the Installation:: Installing.
2060 @node Keyboard Layout and Networking and Partitioning
2061 @subsection Keyboard Layout, Networking, and Partitioning
2063 Before you can install the system, you may want to adjust the keyboard layout,
2064 set up networking, and partition your target hard disk. This section will
2065 guide you through this.
2067 @subsubsection Keyboard Layout
2069 @cindex keyboard layout
2070 The installation image uses the US qwerty keyboard layout. If you want
2071 to change it, you can use the @command{loadkeys} command. For example,
2072 the following command selects the Dvorak keyboard layout:
2078 See the files under @file{/run/current-system/profile/share/keymaps} for
2079 a list of available keyboard layouts. Run @command{man loadkeys} for
2082 @subsubsection Networking
2084 Run the following command to see what your network interfaces are called:
2091 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2097 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2098 Wired interfaces have a name starting with @samp{e}; for example, the
2099 interface corresponding to the first on-board Ethernet controller is
2100 called @samp{eno1}. Wireless interfaces have a name starting with
2101 @samp{w}, like @samp{w1p2s0}.
2104 @item Wired connection
2105 To configure a wired network run the following command, substituting
2106 @var{interface} with the name of the wired interface you want to use.
2109 ifconfig @var{interface} up
2112 @item Wireless connection
2115 To configure wireless networking, you can create a configuration file
2116 for the @command{wpa_supplicant} configuration tool (its location is not
2117 important) using one of the available text editors such as
2121 nano wpa_supplicant.conf
2124 As an example, the following stanza can go to this file and will work
2125 for many wireless networks, provided you give the actual SSID and
2126 passphrase for the network you are connecting to:
2130 ssid="@var{my-ssid}"
2132 psk="the network's secret passphrase"
2136 Start the wireless service and run it in the background with the
2137 following command (substitute @var{interface} with the name of the
2138 network interface you want to use):
2141 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2144 Run @command{man wpa_supplicant} for more information.
2148 At this point, you need to acquire an IP address. On a network where IP
2149 addresses are automatically assigned @i{via} DHCP, you can run:
2152 dhclient -v @var{interface}
2155 Try to ping a server to see if networking is up and running:
2161 Setting up network access is almost always a requirement because the
2162 image does not contain all the software and tools that may be needed.
2164 @cindex installing over SSH
2165 If you want to, you can continue the installation remotely by starting
2169 herd start ssh-daemon
2172 Make sure to either set a password with @command{passwd}, or configure
2173 OpenSSH public key authentication before logging in.
2175 @subsubsection Disk Partitioning
2177 Unless this has already been done, the next step is to partition, and
2178 then format the target partition(s).
2180 The installation image includes several partitioning tools, including
2181 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2182 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2183 the partition layout you want:
2189 If your disk uses the GUID Partition Table (GPT) format and you plan to
2190 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2191 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2194 @cindex EFI, installation
2195 @cindex UEFI, installation
2196 @cindex ESP, EFI system partition
2197 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2198 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2199 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2202 parted /dev/sda set 1 esp on
2206 @vindex grub-bootloader
2207 @vindex grub-efi-bootloader
2208 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2209 @file{/sys/firmware/efi} exists in the installation image, then you should
2210 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2211 Otherwise you should use the BIOS-based GRUB, known as
2212 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2216 Once you are done partitioning the target hard disk drive, you have to
2217 create a file system on the relevant partition(s)@footnote{Currently
2218 Guix System only supports ext4 and btrfs file systems. In particular, code
2219 that reads file system UUIDs and labels only works for these file system
2220 types.}. For the ESP, if you have one and assuming it is
2221 @file{/dev/sda1}, run:
2224 mkfs.fat -F32 /dev/sda1
2227 Preferably, assign file systems a label so that you can easily and
2228 reliably refer to them in @code{file-system} declarations (@pxref{File
2229 Systems}). This is typically done using the @code{-L} option of
2230 @command{mkfs.ext4} and related commands. So, assuming the target root
2231 partition lives at @file{/dev/sda2}, a file system with the label
2232 @code{my-root} can be created with:
2235 mkfs.ext4 -L my-root /dev/sda2
2238 @cindex encrypted disk
2239 If you are instead planning to encrypt the root partition, you can use
2240 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2241 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2242 @code{man cryptsetup}} for more information.) Assuming you want to
2243 store the root partition on @file{/dev/sda2}, the command sequence would
2244 be along these lines:
2247 cryptsetup luksFormat /dev/sda2
2248 cryptsetup open --type luks /dev/sda2 my-partition
2249 mkfs.ext4 -L my-root /dev/mapper/my-partition
2252 Once that is done, mount the target file system under @file{/mnt}
2253 with a command like (again, assuming @code{my-root} is the label of the
2257 mount LABEL=my-root /mnt
2260 Also mount any other file systems you would like to use on the target
2261 system relative to this path. If you have opted for @file{/boot/efi} as an
2262 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2263 found by @code{guix system init} afterwards.
2265 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2266 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2267 sure to initialize them with @command{mkswap}. Assuming you have one
2268 swap partition on @file{/dev/sda3}, you would run:
2275 Alternatively, you may use a swap file. For example, assuming that in
2276 the new system you want to use the file @file{/swapfile} as a swap file,
2277 you would run@footnote{This example will work for many types of file
2278 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2279 btrfs), the required steps may be different. For details, see the
2280 manual pages for @command{mkswap} and @command{swapon}.}:
2283 # This is 10 GiB of swap space. Adjust "count" to change the size.
2284 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2285 # For security, make the file readable and writable only by root.
2286 chmod 600 /mnt/swapfile
2287 mkswap /mnt/swapfile
2288 swapon /mnt/swapfile
2291 Note that if you have encrypted the root partition and created a swap
2292 file in its file system as described above, then the encryption also
2293 protects the swap file, just like any other file in that file system.
2295 @node Proceeding with the Installation
2296 @subsection Proceeding with the Installation
2298 With the target partitions ready and the target root mounted on
2299 @file{/mnt}, we're ready to go. First, run:
2302 herd start cow-store /mnt
2305 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2306 during the installation phase are written to the target disk on @file{/mnt}
2307 rather than kept in memory. This is necessary because the first phase of
2308 the @command{guix system init} command (see below) entails downloads or
2309 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2311 Next, you have to edit a file and
2312 provide the declaration of the operating system to be installed. To
2313 that end, the installation system comes with three text editors. We
2314 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2315 supports syntax highlighting and parentheses matching; other editors
2316 include GNU Zile (an Emacs clone), and
2317 nvi (a clone of the original BSD @command{vi} editor).
2318 We strongly recommend storing that file on the target root file system, say,
2319 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2320 configuration file once you have rebooted into the newly-installed system.
2322 @xref{Using the Configuration System}, for an overview of the
2323 configuration file. The example configurations discussed in that
2324 section are available under @file{/etc/configuration} in the
2325 installation image. Thus, to get started with a system configuration
2326 providing a graphical display server (a ``desktop'' system), you can run
2327 something along these lines:
2331 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2332 # nano /mnt/etc/config.scm
2335 You should pay attention to what your configuration file contains, and
2340 Make sure the @code{bootloader-configuration} form refers to the target
2341 you want to install GRUB on. It should mention @code{grub-bootloader} if
2342 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2343 for newer UEFI systems. For legacy systems, the @code{target} field
2344 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2345 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2346 currently mounted and a @code{file-system} entry is specified in your
2350 Be sure that your file system labels match the value of their respective
2351 @code{device} fields in your @code{file-system} configuration, assuming
2352 your @code{file-system} configuration uses the @code{file-system-label}
2353 procedure in its @code{device} field.
2356 If there are encrypted or RAID partitions, make sure to add a
2357 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2360 Once you are done preparing the configuration file, the new system must
2361 be initialized (remember that the target root file system is mounted
2365 guix system init /mnt/etc/config.scm /mnt
2369 This copies all the necessary files and installs GRUB on
2370 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2371 more information, @pxref{Invoking guix system}. This command may trigger
2372 downloads or builds of missing packages, which can take some time.
2374 Once that command has completed---and hopefully succeeded!---you can run
2375 @command{reboot} and boot into the new system. The @code{root} password
2376 in the new system is initially empty; other users' passwords need to be
2377 initialized by running the @command{passwd} command as @code{root},
2378 unless your configuration specifies otherwise
2379 (@pxref{user-account-password, user account passwords}).
2380 @xref{After System Installation}, for what's next!
2383 @node After System Installation
2384 @section After System Installation
2386 Success, you've now booted into Guix System! From then on, you can update the
2387 system whenever you want by running, say:
2391 sudo guix system reconfigure /etc/config.scm
2395 This builds a new system generation with the latest packages and services
2396 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2397 your system includes the latest security updates (@pxref{Security Updates}).
2399 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2401 @cindex sudo vs. @command{guix pull}
2402 Note that @command{sudo guix} runs your user's @command{guix} command and
2403 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2404 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2407 Join us on @code{#guix} on the Freenode IRC network or on
2408 @email{guix-devel@@gnu.org} to share your experience!
2411 @node Installing Guix in a VM
2412 @section Installing Guix in a Virtual Machine
2414 @cindex virtual machine, Guix System installation
2415 @cindex virtual private server (VPS)
2416 @cindex VPS (virtual private server)
2417 If you'd like to install Guix System in a virtual machine (VM) or on a
2418 virtual private server (VPS) rather than on your beloved machine, this
2421 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2422 disk image, follow these steps:
2426 First, retrieve and decompress the Guix system installation image as
2427 described previously (@pxref{USB Stick and DVD Installation}).
2430 Create a disk image that will hold the installed system. To make a
2431 qcow2-formatted disk image, use the @command{qemu-img} command:
2434 qemu-img create -f qcow2 guixsd.img 50G
2437 The resulting file will be much smaller than 50 GB (typically less than
2438 1 MB), but it will grow as the virtualized storage device is filled up.
2441 Boot the USB installation image in an VM:
2444 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2445 -net user -net nic,model=virtio -boot menu=on \
2446 -drive file=guix-system-install-@value{VERSION}.@var{system}.iso \
2447 -drive file=guixsd.img
2450 The ordering of the drives matters. @code{-enable-kvm} is optional, but
2451 significantly improves performance, @pxref{Running Guix in a VM}.
2453 In the VM console, quickly press the @kbd{F12} key to enter the boot
2454 menu. Then press the @kbd{2} key and the @kbd{RET} key to validate your
2458 You're now root in the VM, proceed with the installation process.
2459 @xref{Preparing for Installation}, and follow the instructions.
2462 Once installation is complete, you can boot the system that's on your
2463 @file{guixsd.img} image. @xref{Running Guix in a VM}, for how to do
2466 @node Building the Installation Image
2467 @section Building the Installation Image
2469 @cindex installation image
2470 The installation image described above was built using the @command{guix
2471 system} command, specifically:
2474 guix system disk-image --file-system-type=iso9660 \
2475 gnu/system/install.scm
2478 Have a look at @file{gnu/system/install.scm} in the source tree,
2479 and see also @ref{Invoking guix system} for more information
2480 about the installation image.
2482 @section Building the Installation Image for ARM Boards
2484 Many ARM boards require a specific variant of the
2485 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2487 If you build a disk image and the bootloader is not available otherwise
2488 (on another boot drive etc), it's advisable to build an image that
2489 includes the bootloader, specifically:
2492 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2495 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2496 board, a list of possible boards will be printed.
2498 @c *********************************************************************
2499 @node Package Management
2500 @chapter Package Management
2503 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2504 remove software packages, without having to know about their build
2505 procedures or dependencies. Guix also goes beyond this obvious set of
2508 This chapter describes the main features of Guix, as well as the
2509 package management tools it provides. Along with the command-line
2510 interface described below (@pxref{Invoking guix package, @code{guix
2511 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2512 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2513 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2517 guix install emacs-guix
2521 * Features:: How Guix will make your life brighter.
2522 * Invoking guix package:: Package installation, removal, etc.
2523 * Substitutes:: Downloading pre-built binaries.
2524 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2525 * Invoking guix gc:: Running the garbage collector.
2526 * Invoking guix pull:: Fetching the latest Guix and distribution.
2527 * Channels:: Customizing the package collection.
2528 * Inferiors:: Interacting with another revision of Guix.
2529 * Invoking guix describe:: Display information about your Guix revision.
2530 * Invoking guix archive:: Exporting and importing store files.
2536 When using Guix, each package ends up in the @dfn{package store}, in its
2537 own directory---something that resembles
2538 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2540 Instead of referring to these directories, users have their own
2541 @dfn{profile}, which points to the packages that they actually want to
2542 use. These profiles are stored within each user's home directory, at
2543 @code{$HOME/.guix-profile}.
2545 For example, @code{alice} installs GCC 4.7.2. As a result,
2546 @file{/home/alice/.guix-profile/bin/gcc} points to
2547 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2548 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2549 simply continues to point to
2550 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2551 coexist on the same system without any interference.
2553 The @command{guix package} command is the central tool to manage
2554 packages (@pxref{Invoking guix package}). It operates on the per-user
2555 profiles, and can be used @emph{with normal user privileges}.
2557 @cindex transactions
2558 The command provides the obvious install, remove, and upgrade
2559 operations. Each invocation is actually a @emph{transaction}: either
2560 the specified operation succeeds, or nothing happens. Thus, if the
2561 @command{guix package} process is terminated during the transaction,
2562 or if a power outage occurs during the transaction, then the user's
2563 profile remains in its previous state, and remains usable.
2565 In addition, any package transaction may be @emph{rolled back}. So, if,
2566 for example, an upgrade installs a new version of a package that turns
2567 out to have a serious bug, users may roll back to the previous instance
2568 of their profile, which was known to work well. Similarly, the global
2569 system configuration on Guix is subject to
2570 transactional upgrades and roll-back
2571 (@pxref{Using the Configuration System}).
2573 All packages in the package store may be @emph{garbage-collected}.
2574 Guix can determine which packages are still referenced by user
2575 profiles, and remove those that are provably no longer referenced
2576 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2577 generations of their profile so that the packages they refer to can be
2580 @cindex reproducibility
2581 @cindex reproducible builds
2582 Guix takes a @dfn{purely functional} approach to package
2583 management, as described in the introduction (@pxref{Introduction}).
2584 Each @file{/gnu/store} package directory name contains a hash of all the
2585 inputs that were used to build that package---compiler, libraries, build
2586 scripts, etc. This direct correspondence allows users to make sure a
2587 given package installation matches the current state of their
2588 distribution. It also helps maximize @dfn{build reproducibility}:
2589 thanks to the isolated build environments that are used, a given build
2590 is likely to yield bit-identical files when performed on different
2591 machines (@pxref{Invoking guix-daemon, container}).
2594 This foundation allows Guix to support @dfn{transparent binary/source
2595 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2596 available from an external source---a @dfn{substitute}, Guix just
2597 downloads it and unpacks it;
2598 otherwise, it builds the package from source, locally
2599 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2600 reproducible, users do not have to trust servers that provide
2601 substitutes: they can force a local build and @emph{challenge} providers
2602 (@pxref{Invoking guix challenge}).
2604 Control over the build environment is a feature that is also useful for
2605 developers. The @command{guix environment} command allows developers of
2606 a package to quickly set up the right development environment for their
2607 package, without having to manually install the dependencies of the
2608 package into their profile (@pxref{Invoking guix environment}).
2610 @cindex replication, of software environments
2611 @cindex provenance tracking, of software artifacts
2612 All of Guix and its package definitions is version-controlled, and
2613 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2614 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2615 Guix instance on a different machine or at a later point in time, which in
2616 turn allows you to @emph{replicate complete software environments}, while
2617 retaining precise @dfn{provenance tracking} of the software.
2619 @node Invoking guix package
2620 @section Invoking @command{guix package}
2622 @cindex installing packages
2623 @cindex removing packages
2624 @cindex package installation
2625 @cindex package removal
2626 The @command{guix package} command is the tool that allows users to
2627 install, upgrade, and remove packages, as well as rolling back to
2628 previous configurations. It operates only on the user's own profile,
2629 and works with normal user privileges (@pxref{Features}). Its syntax
2633 guix package @var{options}
2636 @cindex transactions
2637 Primarily, @var{options} specifies the operations to be performed during
2638 the transaction. Upon completion, a new profile is created, but
2639 previous @dfn{generations} of the profile remain available, should the user
2642 For example, to remove @code{lua} and install @code{guile} and
2643 @code{guile-cairo} in a single transaction:
2646 guix package -r lua -i guile guile-cairo
2649 @cindex aliases, for @command{guix package}
2650 For your convenience, we also provide the following aliases:
2654 @command{guix search} is an alias for @command{guix package -s},
2656 @command{guix install} is an alias for @command{guix package -i},
2658 @command{guix remove} is an alias for @command{guix package -r},
2660 and @command{guix upgrade} is an alias for @command{guix package -u}.
2663 These aliases are less expressive than @command{guix package} and provide
2664 fewer options, so in some cases you'll probably want to use @command{guix
2667 @command{guix package} also supports a @dfn{declarative approach}
2668 whereby the user specifies the exact set of packages to be available and
2669 passes it @i{via} the @option{--manifest} option
2670 (@pxref{profile-manifest, @option{--manifest}}).
2673 For each user, a symlink to the user's default profile is automatically
2674 created in @file{$HOME/.guix-profile}. This symlink always points to the
2675 current generation of the user's default profile. Thus, users can add
2676 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2677 variable, and so on.
2678 @cindex search paths
2679 If you are not using Guix System, consider adding the
2680 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2681 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2682 shells get all the right environment variable definitions:
2685 GUIX_PROFILE="$HOME/.guix-profile" ; \
2686 source "$HOME/.guix-profile/etc/profile"
2689 In a multi-user setup, user profiles are stored in a place registered as
2690 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2691 to (@pxref{Invoking guix gc}). That directory is normally
2692 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2693 @var{localstatedir} is the value passed to @code{configure} as
2694 @code{--localstatedir}, and @var{user} is the user name. The
2695 @file{per-user} directory is created when @command{guix-daemon} is
2696 started, and the @var{user} sub-directory is created by @command{guix
2699 The @var{options} can be among the following:
2703 @item --install=@var{package} @dots{}
2704 @itemx -i @var{package} @dots{}
2705 Install the specified @var{package}s.
2707 Each @var{package} may specify either a simple package name, such as
2708 @code{guile}, or a package name followed by an at-sign and version number,
2709 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2710 case, the newest version prefixed by @code{1.8} is selected.)
2712 If no version number is specified, the
2713 newest available version will be selected. In addition, @var{package}
2714 may contain a colon, followed by the name of one of the outputs of the
2715 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2716 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2717 name (and optionally version) are searched for among the GNU
2718 distribution modules (@pxref{Package Modules}).
2720 @cindex propagated inputs
2721 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2722 that automatically get installed along with the required package
2723 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2724 @code{package} objects}, for information about propagated inputs in
2725 package definitions).
2727 @anchor{package-cmd-propagated-inputs}
2728 An example is the GNU MPC library: its C header files refer to those of
2729 the GNU MPFR library, which in turn refer to those of the GMP library.
2730 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2731 in the profile; removing MPC also removes MPFR and GMP---unless they had
2732 also been explicitly installed by the user.
2734 Besides, packages sometimes rely on the definition of environment
2735 variables for their search paths (see explanation of
2736 @code{--search-paths} below). Any missing or possibly incorrect
2737 environment variable definitions are reported here.
2739 @item --install-from-expression=@var{exp}
2741 Install the package @var{exp} evaluates to.
2743 @var{exp} must be a Scheme expression that evaluates to a
2744 @code{<package>} object. This option is notably useful to disambiguate
2745 between same-named variants of a package, with expressions such as
2746 @code{(@@ (gnu packages base) guile-final)}.
2748 Note that this option installs the first output of the specified
2749 package, which may be insufficient when needing a specific output of a
2750 multiple-output package.
2752 @item --install-from-file=@var{file}
2753 @itemx -f @var{file}
2754 Install the package that the code within @var{file} evaluates to.
2756 As an example, @var{file} might contain a definition like this
2757 (@pxref{Defining Packages}):
2760 @verbatiminclude package-hello.scm
2763 Developers may find it useful to include such a @file{guix.scm} file
2764 in the root of their project source tree that can be used to test
2765 development snapshots and create reproducible development environments
2766 (@pxref{Invoking guix environment}).
2768 @item --remove=@var{package} @dots{}
2769 @itemx -r @var{package} @dots{}
2770 Remove the specified @var{package}s.
2772 As for @code{--install}, each @var{package} may specify a version number
2773 and/or output name in addition to the package name. For instance,
2774 @code{-r glibc:debug} would remove the @code{debug} output of
2777 @item --upgrade[=@var{regexp} @dots{}]
2778 @itemx -u [@var{regexp} @dots{}]
2779 @cindex upgrading packages
2780 Upgrade all the installed packages. If one or more @var{regexp}s are
2781 specified, upgrade only installed packages whose name matches a
2782 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2784 Note that this upgrades package to the latest version of packages found
2785 in the distribution currently installed. To update your distribution,
2786 you should regularly run @command{guix pull} (@pxref{Invoking guix
2789 @item --do-not-upgrade[=@var{regexp} @dots{}]
2790 When used together with the @code{--upgrade} option, do @emph{not}
2791 upgrade any packages whose name matches a @var{regexp}. For example, to
2792 upgrade all packages in the current profile except those containing the
2793 substring ``emacs'':
2796 $ guix package --upgrade . --do-not-upgrade emacs
2799 @item @anchor{profile-manifest}--manifest=@var{file}
2800 @itemx -m @var{file}
2801 @cindex profile declaration
2802 @cindex profile manifest
2803 Create a new generation of the profile from the manifest object
2804 returned by the Scheme code in @var{file}.
2806 This allows you to @emph{declare} the profile's contents rather than
2807 constructing it through a sequence of @code{--install} and similar
2808 commands. The advantage is that @var{file} can be put under version
2809 control, copied to different machines to reproduce the same profile, and
2812 @c FIXME: Add reference to (guix profile) documentation when available.
2813 @var{file} must return a @dfn{manifest} object, which is roughly a list
2816 @findex packages->manifest
2818 (use-package-modules guile emacs)
2823 ;; Use a specific package output.
2824 (list guile-2.0 "debug")))
2827 @findex specifications->manifest
2828 In this example we have to know which modules define the @code{emacs}
2829 and @code{guile-2.0} variables to provide the right
2830 @code{use-package-modules} line, which can be cumbersome. We can
2831 instead provide regular package specifications and let
2832 @code{specifications->manifest} look up the corresponding package
2836 (specifications->manifest
2837 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2841 @cindex rolling back
2842 @cindex undoing transactions
2843 @cindex transactions, undoing
2844 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2845 the last transaction.
2847 When combined with options such as @code{--install}, roll back occurs
2848 before any other actions.
2850 When rolling back from the first generation that actually contains
2851 installed packages, the profile is made to point to the @dfn{zeroth
2852 generation}, which contains no files apart from its own metadata.
2854 After having rolled back, installing, removing, or upgrading packages
2855 overwrites previous future generations. Thus, the history of the
2856 generations in a profile is always linear.
2858 @item --switch-generation=@var{pattern}
2859 @itemx -S @var{pattern}
2861 Switch to a particular generation defined by @var{pattern}.
2863 @var{pattern} may be either a generation number or a number prefixed
2864 with ``+'' or ``-''. The latter means: move forward/backward by a
2865 specified number of generations. For example, if you want to return to
2866 the latest generation after @code{--roll-back}, use
2867 @code{--switch-generation=+1}.
2869 The difference between @code{--roll-back} and
2870 @code{--switch-generation=-1} is that @code{--switch-generation} will
2871 not make a zeroth generation, so if a specified generation does not
2872 exist, the current generation will not be changed.
2874 @item --search-paths[=@var{kind}]
2875 @cindex search paths
2876 Report environment variable definitions, in Bash syntax, that may be
2877 needed in order to use the set of installed packages. These environment
2878 variables are used to specify @dfn{search paths} for files used by some
2879 of the installed packages.
2881 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2882 environment variables to be defined so it can look for headers and
2883 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2884 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2885 library are installed in the profile, then @code{--search-paths} will
2886 suggest setting these variables to @code{@var{profile}/include} and
2887 @code{@var{profile}/lib}, respectively.
2889 The typical use case is to define these environment variables in the
2893 $ eval `guix package --search-paths`
2896 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2897 meaning that the returned environment variable definitions will either
2898 be exact settings, or prefixes or suffixes of the current value of these
2899 variables. When omitted, @var{kind} defaults to @code{exact}.
2901 This option can also be used to compute the @emph{combined} search paths
2902 of several profiles. Consider this example:
2905 $ guix package -p foo -i guile
2906 $ guix package -p bar -i guile-json
2907 $ guix package -p foo -p bar --search-paths
2910 The last command above reports about the @code{GUILE_LOAD_PATH}
2911 variable, even though, taken individually, neither @file{foo} nor
2912 @file{bar} would lead to that recommendation.
2915 @item --profile=@var{profile}
2916 @itemx -p @var{profile}
2917 Use @var{profile} instead of the user's default profile.
2919 @cindex collisions, in a profile
2920 @cindex colliding packages in profiles
2921 @cindex profile collisions
2922 @item --allow-collisions
2923 Allow colliding packages in the new profile. Use at your own risk!
2925 By default, @command{guix package} reports as an error @dfn{collisions}
2926 in the profile. Collisions happen when two or more different versions
2927 or variants of a given package end up in the profile.
2930 Use the bootstrap Guile to build the profile. This option is only
2931 useful to distribution developers.
2935 In addition to these actions, @command{guix package} supports the
2936 following options to query the current state of a profile, or the
2937 availability of packages:
2941 @item --search=@var{regexp}
2942 @itemx -s @var{regexp}
2943 @cindex searching for packages
2944 List the available packages whose name, synopsis, or description matches
2945 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
2946 Print all the metadata of matching packages in
2947 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
2948 GNU recutils manual}).
2950 This allows specific fields to be extracted using the @command{recsel}
2951 command, for instance:
2954 $ guix package -s malloc | recsel -p name,version,relevance
2968 Similarly, to show the name of all the packages available under the
2969 terms of the GNU@tie{}LGPL version 3:
2972 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
2979 It is also possible to refine search results using several @code{-s} flags to
2980 @command{guix package}, or several arguments to @command{guix search}. For
2981 example, the following command returns a list of board games (this time using
2982 the @command{guix search} alias):
2985 $ guix search '\<board\>' game | recsel -p name
2990 If we were to omit @code{-s game}, we would also get software packages
2991 that deal with printed circuit boards; removing the angle brackets
2992 around @code{board} would further add packages that have to do with
2995 And now for a more elaborate example. The following command searches
2996 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
2997 libraries, and prints the name and synopsis of the matching packages:
3000 $ guix search crypto library | \
3001 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3005 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3006 information on @dfn{selection expressions} for @code{recsel -e}.
3008 @item --show=@var{package}
3009 Show details about @var{package}, taken from the list of available packages, in
3010 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3014 $ guix package --show=python | recsel -p name,version
3022 You may also specify the full name of a package to only get details about a
3023 specific version of it:
3025 $ guix package --show=python@@3.4 | recsel -p name,version
3032 @item --list-installed[=@var{regexp}]
3033 @itemx -I [@var{regexp}]
3034 List the currently installed packages in the specified profile, with the
3035 most recently installed packages shown last. When @var{regexp} is
3036 specified, list only installed packages whose name matches @var{regexp}.
3038 For each installed package, print the following items, separated by
3039 tabs: the package name, its version string, the part of the package that
3040 is installed (for instance, @code{out} for the default output,
3041 @code{include} for its headers, etc.), and the path of this package in
3044 @item --list-available[=@var{regexp}]
3045 @itemx -A [@var{regexp}]
3046 List packages currently available in the distribution for this system
3047 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3048 installed packages whose name matches @var{regexp}.
3050 For each package, print the following items separated by tabs: its name,
3051 its version string, the parts of the package (@pxref{Packages with
3052 Multiple Outputs}), and the source location of its definition.
3054 @item --list-generations[=@var{pattern}]
3055 @itemx -l [@var{pattern}]
3057 Return a list of generations along with their creation dates; for each
3058 generation, show the installed packages, with the most recently
3059 installed packages shown last. Note that the zeroth generation is never
3062 For each installed package, print the following items, separated by
3063 tabs: the name of a package, its version string, the part of the package
3064 that is installed (@pxref{Packages with Multiple Outputs}), and the
3065 location of this package in the store.
3067 When @var{pattern} is used, the command returns only matching
3068 generations. Valid patterns include:
3071 @item @emph{Integers and comma-separated integers}. Both patterns denote
3072 generation numbers. For instance, @code{--list-generations=1} returns
3075 And @code{--list-generations=1,8,2} outputs three generations in the
3076 specified order. Neither spaces nor trailing commas are allowed.
3078 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3079 specified generations and everything in between. Note that the start of
3080 a range must be smaller than its end.
3082 It is also possible to omit the endpoint. For example,
3083 @code{--list-generations=2..}, returns all generations starting from the
3086 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3087 or months by passing an integer along with the first letter of the
3088 duration. For example, @code{--list-generations=20d} lists generations
3089 that are up to 20 days old.
3092 @item --delete-generations[=@var{pattern}]
3093 @itemx -d [@var{pattern}]
3094 When @var{pattern} is omitted, delete all generations except the current
3097 This command accepts the same patterns as @option{--list-generations}.
3098 When @var{pattern} is specified, delete the matching generations. When
3099 @var{pattern} specifies a duration, generations @emph{older} than the
3100 specified duration match. For instance, @code{--delete-generations=1m}
3101 deletes generations that are more than one month old.
3103 If the current generation matches, it is @emph{not} deleted. Also, the
3104 zeroth generation is never deleted.
3106 Note that deleting generations prevents rolling back to them.
3107 Consequently, this command must be used with care.
3111 Finally, since @command{guix package} may actually start build
3112 processes, it supports all the common build options (@pxref{Common Build
3113 Options}). It also supports package transformation options, such as
3114 @option{--with-source} (@pxref{Package Transformation Options}).
3115 However, note that package transformations are lost when upgrading; to
3116 preserve transformations across upgrades, you should define your own
3117 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3118 (@pxref{Defining Packages}).
3121 @section Substitutes
3124 @cindex pre-built binaries
3125 Guix supports transparent source/binary deployment, which means that it
3126 can either build things locally, or download pre-built items from a
3127 server, or both. We call these pre-built items @dfn{substitutes}---they
3128 are substitutes for local build results. In many cases, downloading a
3129 substitute is much faster than building things locally.
3131 Substitutes can be anything resulting from a derivation build
3132 (@pxref{Derivations}). Of course, in the common case, they are
3133 pre-built package binaries, but source tarballs, for instance, which
3134 also result from derivation builds, can be available as substitutes.
3137 * Official Substitute Server:: One particular source of substitutes.
3138 * Substitute Server Authorization:: How to enable or disable substitutes.
3139 * Substitute Authentication:: How Guix verifies substitutes.
3140 * Proxy Settings:: How to get substitutes via proxy.
3141 * Substitution Failure:: What happens when substitution fails.
3142 * On Trusting Binaries:: How can you trust that binary blob?
3145 @node Official Substitute Server
3146 @subsection Official Substitute Server
3149 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3150 that builds packages from Guix continuously for some
3151 architectures, and makes them available as substitutes. This is the
3152 default source of substitutes; it can be overridden by passing the
3153 @option{--substitute-urls} option either to @command{guix-daemon}
3154 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3155 or to client tools such as @command{guix package}
3156 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3159 Substitute URLs can be either HTTP or HTTPS.
3160 HTTPS is recommended because communications are encrypted; conversely,
3161 using HTTP makes all communications visible to an eavesdropper, who
3162 could use the information gathered to determine, for instance, whether
3163 your system has unpatched security vulnerabilities.
3165 Substitutes from the official build farm are enabled by default when
3166 using Guix System (@pxref{GNU Distribution}). However,
3167 they are disabled by default when using Guix on a foreign distribution,
3168 unless you have explicitly enabled them via one of the recommended
3169 installation steps (@pxref{Installation}). The following paragraphs
3170 describe how to enable or disable substitutes for the official build
3171 farm; the same procedure can also be used to enable substitutes for any
3172 other substitute server.
3174 @node Substitute Server Authorization
3175 @subsection Substitute Server Authorization
3178 @cindex substitutes, authorization thereof
3179 @cindex access control list (ACL), for substitutes
3180 @cindex ACL (access control list), for substitutes
3181 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3183 must add its public key to the access control list (ACL) of archive
3184 imports, using the @command{guix archive} command (@pxref{Invoking guix
3185 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3186 be compromised and to serve genuine substitutes.
3188 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3189 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3190 the installation prefix of Guix. If you installed Guix from source,
3191 make sure you checked the GPG signature of
3192 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3193 Then, you can run something like this:
3196 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3199 Once this is in place, the output of a command like @code{guix build}
3200 should change from something like:
3203 $ guix build emacs --dry-run
3204 The following derivations would be built:
3205 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3206 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3207 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3208 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3216 $ guix build emacs --dry-run
3217 112.3 MB would be downloaded:
3218 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3219 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3220 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3221 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3226 This indicates that substitutes from @code{@value{SUBSTITUTE-SERVER}} are usable and
3227 will be downloaded, when possible, for future builds.
3229 @cindex substitutes, how to disable
3230 The substitute mechanism can be disabled globally by running
3231 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3232 guix-daemon}). It can also be disabled temporarily by passing the
3233 @code{--no-substitutes} option to @command{guix package}, @command{guix
3234 build}, and other command-line tools.
3236 @node Substitute Authentication
3237 @subsection Substitute Authentication
3239 @cindex digital signatures
3240 Guix detects and raises an error when attempting to use a substitute
3241 that has been tampered with. Likewise, it ignores substitutes that are
3242 not signed, or that are not signed by one of the keys listed in the ACL.
3244 There is one exception though: if an unauthorized server provides
3245 substitutes that are @emph{bit-for-bit identical} to those provided by
3246 an authorized server, then the unauthorized server becomes eligible for
3247 downloads. For example, assume we have chosen two substitute servers
3251 --substitute-urls="https://a.example.org https://b.example.org"
3255 @cindex reproducible builds
3256 If the ACL contains only the key for @code{b.example.org}, and if
3257 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3258 then Guix will download substitutes from @code{a.example.org} because it
3259 comes first in the list and can be considered a mirror of
3260 @code{b.example.org}. In practice, independent build machines usually
3261 produce the same binaries, thanks to bit-reproducible builds (see
3264 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3265 (in other words, the server is not authenticated), contrary to what
3266 HTTPS clients such as Web browsers usually do. This is because Guix
3267 authenticates substitute information itself, as explained above, which
3268 is what we care about (whereas X.509 certificates are about
3269 authenticating bindings between domain names and public keys.)
3271 @node Proxy Settings
3272 @subsection Proxy Settings
3275 Substitutes are downloaded over HTTP or HTTPS.
3276 The @code{http_proxy} environment
3277 variable can be set in the environment of @command{guix-daemon} and is
3278 honored for downloads of substitutes. Note that the value of
3279 @code{http_proxy} in the environment where @command{guix build},
3280 @command{guix package}, and other client commands are run has
3281 @emph{absolutely no effect}.
3283 @node Substitution Failure
3284 @subsection Substitution Failure
3286 Even when a substitute for a derivation is available, sometimes the
3287 substitution attempt will fail. This can happen for a variety of
3288 reasons: the substitute server might be offline, the substitute may
3289 recently have been deleted, the connection might have been interrupted,
3292 When substitutes are enabled and a substitute for a derivation is
3293 available, but the substitution attempt fails, Guix will attempt to
3294 build the derivation locally depending on whether or not
3295 @code{--fallback} was given (@pxref{fallback-option,, common build
3296 option @code{--fallback}}). Specifically, if @code{--fallback} was
3297 omitted, then no local build will be performed, and the derivation is
3298 considered to have failed. However, if @code{--fallback} was given,
3299 then Guix will attempt to build the derivation locally, and the success
3300 or failure of the derivation depends on the success or failure of the
3301 local build. Note that when substitutes are disabled or no substitute
3302 is available for the derivation in question, a local build will
3303 @emph{always} be performed, regardless of whether or not
3304 @code{--fallback} was given.
3306 To get an idea of how many substitutes are available right now, you can
3307 try running the @command{guix weather} command (@pxref{Invoking guix
3308 weather}). This command provides statistics on the substitutes provided
3311 @node On Trusting Binaries
3312 @subsection On Trusting Binaries
3314 @cindex trust, of pre-built binaries
3315 Today, each individual's control over their own computing is at the
3316 mercy of institutions, corporations, and groups with enough power and
3317 determination to subvert the computing infrastructure and exploit its
3318 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3319 convenient, we encourage users to also build on their own, or even run
3320 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3321 interesting target. One way to help is by publishing the software you
3322 build using @command{guix publish} so that others have one more choice
3323 of server to download substitutes from (@pxref{Invoking guix publish}).
3325 Guix has the foundations to maximize build reproducibility
3326 (@pxref{Features}). In most cases, independent builds of a given
3327 package or derivation should yield bit-identical results. Thus, through
3328 a diverse set of independent package builds, we can strengthen the
3329 integrity of our systems. The @command{guix challenge} command aims to
3330 help users assess substitute servers, and to assist developers in
3331 finding out about non-deterministic package builds (@pxref{Invoking guix
3332 challenge}). Similarly, the @option{--check} option of @command{guix
3333 build} allows users to check whether previously-installed substitutes
3334 are genuine by rebuilding them locally (@pxref{build-check,
3335 @command{guix build --check}}).
3337 In the future, we want Guix to have support to publish and retrieve
3338 binaries to/from other users, in a peer-to-peer fashion. If you would
3339 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3341 @node Packages with Multiple Outputs
3342 @section Packages with Multiple Outputs
3344 @cindex multiple-output packages
3345 @cindex package outputs
3348 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3349 source package leads to exactly one directory in the store. When running
3350 @command{guix install glibc}, one installs the default output of the
3351 GNU libc package; the default output is called @code{out}, but its name
3352 can be omitted as shown in this command. In this particular case, the
3353 default output of @code{glibc} contains all the C header files, shared
3354 libraries, static libraries, Info documentation, and other supporting
3357 Sometimes it is more appropriate to separate the various types of files
3358 produced from a single source package into separate outputs. For
3359 instance, the GLib C library (used by GTK+ and related packages)
3360 installs more than 20 MiB of reference documentation as HTML pages.
3361 To save space for users who do not need it, the documentation goes to a
3362 separate output, called @code{doc}. To install the main GLib output,
3363 which contains everything but the documentation, one would run:
3369 @cindex documentation
3370 The command to install its documentation is:
3373 guix install glib:doc
3376 Some packages install programs with different ``dependency footprints''.
3377 For instance, the WordNet package installs both command-line tools and
3378 graphical user interfaces (GUIs). The former depend solely on the C
3379 library, whereas the latter depend on Tcl/Tk and the underlying X
3380 libraries. In this case, we leave the command-line tools in the default
3381 output, whereas the GUIs are in a separate output. This allows users
3382 who do not need the GUIs to save space. The @command{guix size} command
3383 can help find out about such situations (@pxref{Invoking guix size}).
3384 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3386 There are several such multiple-output packages in the GNU distribution.
3387 Other conventional output names include @code{lib} for libraries and
3388 possibly header files, @code{bin} for stand-alone programs, and
3389 @code{debug} for debugging information (@pxref{Installing Debugging
3390 Files}). The outputs of a packages are listed in the third column of
3391 the output of @command{guix package --list-available} (@pxref{Invoking
3395 @node Invoking guix gc
3396 @section Invoking @command{guix gc}
3398 @cindex garbage collector
3400 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3401 The @command{guix gc} command allows users to explicitly run the garbage
3402 collector to reclaim space from the @file{/gnu/store} directory. It is
3403 the @emph{only} way to remove files from @file{/gnu/store}---removing
3404 files or directories manually may break it beyond repair!
3407 @cindex garbage collector roots
3408 The garbage collector has a set of known @dfn{roots}: any file under
3409 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3410 cannot be deleted; any other file is considered @dfn{dead} and may be
3411 deleted. The set of garbage collector roots (``GC roots'' for short)
3412 includes default user profiles; by default, the symlinks under
3413 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3414 added with @command{guix build --root}, for example (@pxref{Invoking
3415 guix build}). The @command{guix gc --list-roots} command lists them.
3417 Prior to running @code{guix gc --collect-garbage} to make space, it is
3418 often useful to remove old generations from user profiles; that way, old
3419 package builds referenced by those generations can be reclaimed. This
3420 is achieved by running @code{guix package --delete-generations}
3421 (@pxref{Invoking guix package}).
3423 Our recommendation is to run a garbage collection periodically, or when
3424 you are short on disk space. For instance, to guarantee that at least
3425 5@tie{}GB are available on your disk, simply run:
3431 It is perfectly safe to run as a non-interactive periodic job
3432 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3433 Running @command{guix gc} with no arguments will collect as
3434 much garbage as it can, but that is often inconvenient: you may find
3435 yourself having to rebuild or re-download software that is ``dead'' from
3436 the GC viewpoint but that is necessary to build other pieces of
3437 software---e.g., the compiler tool chain.
3439 The @command{guix gc} command has three modes of operation: it can be
3440 used to garbage-collect any dead files (the default), to delete specific
3441 files (the @code{--delete} option), to print garbage-collector
3442 information, or for more advanced queries. The garbage collection
3443 options are as follows:
3446 @item --collect-garbage[=@var{min}]
3447 @itemx -C [@var{min}]
3448 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3449 sub-directories. This is the default operation when no option is
3452 When @var{min} is given, stop once @var{min} bytes have been collected.
3453 @var{min} may be a number of bytes, or it may include a unit as a
3454 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3455 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3457 When @var{min} is omitted, collect all the garbage.
3459 @item --free-space=@var{free}
3460 @itemx -F @var{free}
3461 Collect garbage until @var{free} space is available under
3462 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3463 as @code{500MiB}, as described above.
3465 When @var{free} or more is already available in @file{/gnu/store}, do
3466 nothing and exit immediately.
3468 @item --delete-generations[=@var{duration}]
3469 @itemx -d [@var{duration}]
3470 Before starting the garbage collection process, delete all the generations
3471 older than @var{duration}, for all the user profiles; when run as root, this
3472 applies to all the profiles @emph{of all the users}.
3474 For example, this command deletes all the generations of all your profiles
3475 that are older than 2 months (except generations that are current), and then
3476 proceeds to free space until at least 10 GiB are available:
3479 guix gc -d 2m -F 10G
3484 Attempt to delete all the store files and directories specified as
3485 arguments. This fails if some of the files are not in the store, or if
3486 they are still live.
3488 @item --list-failures
3489 List store items corresponding to cached build failures.
3491 This prints nothing unless the daemon was started with
3492 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3493 @option{--cache-failures}}).
3496 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3500 List store items in use by currently running processes. These store
3501 items are effectively considered GC roots: they cannot be deleted.
3503 @item --clear-failures
3504 Remove the specified store items from the failed-build cache.
3506 Again, this option only makes sense when the daemon is started with
3507 @option{--cache-failures}. Otherwise, it does nothing.
3510 Show the list of dead files and directories still present in the
3511 store---i.e., files and directories no longer reachable from any root.
3514 Show the list of live store files and directories.
3518 In addition, the references among existing store files can be queried:
3524 @cindex package dependencies
3525 List the references (respectively, the referrers) of store files given
3531 List the requisites of the store files passed as arguments. Requisites
3532 include the store files themselves, their references, and the references
3533 of these, recursively. In other words, the returned list is the
3534 @dfn{transitive closure} of the store files.
3536 @xref{Invoking guix size}, for a tool to profile the size of the closure
3537 of an element. @xref{Invoking guix graph}, for a tool to visualize
3538 the graph of references.
3542 Return the derivation(s) leading to the given store items
3543 (@pxref{Derivations}).
3545 For example, this command:
3548 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3552 returns the @file{.drv} file(s) leading to the @code{emacs} package
3553 installed in your profile.
3555 Note that there may be zero matching @file{.drv} files, for instance
3556 because these files have been garbage-collected. There can also be more
3557 than one matching @file{.drv} due to fixed-output derivations.
3560 Lastly, the following options allow you to check the integrity of the
3561 store and to control disk usage.
3565 @item --verify[=@var{options}]
3566 @cindex integrity, of the store
3567 @cindex integrity checking
3568 Verify the integrity of the store.
3570 By default, make sure that all the store items marked as valid in the
3571 database of the daemon actually exist in @file{/gnu/store}.
3573 When provided, @var{options} must be a comma-separated list containing one
3574 or more of @code{contents} and @code{repair}.
3576 When passing @option{--verify=contents}, the daemon computes the
3577 content hash of each store item and compares it against its hash in the
3578 database. Hash mismatches are reported as data corruptions. Because it
3579 traverses @emph{all the files in the store}, this command can take a
3580 long time, especially on systems with a slow disk drive.
3582 @cindex repairing the store
3583 @cindex corruption, recovering from
3584 Using @option{--verify=repair} or @option{--verify=contents,repair}
3585 causes the daemon to try to repair corrupt store items by fetching
3586 substitutes for them (@pxref{Substitutes}). Because repairing is not
3587 atomic, and thus potentially dangerous, it is available only to the
3588 system administrator. A lightweight alternative, when you know exactly
3589 which items in the store are corrupt, is @command{guix build --repair}
3590 (@pxref{Invoking guix build}).
3593 @cindex deduplication
3594 Optimize the store by hard-linking identical files---this is
3595 @dfn{deduplication}.
3597 The daemon performs deduplication after each successful build or archive
3598 import, unless it was started with @code{--disable-deduplication}
3599 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3600 this option is primarily useful when the daemon was running with
3601 @code{--disable-deduplication}.
3605 @node Invoking guix pull
3606 @section Invoking @command{guix pull}
3608 @cindex upgrading Guix
3609 @cindex updating Guix
3610 @cindex @command{guix pull}
3612 Packages are installed or upgraded to the latest version available in
3613 the distribution currently available on your local machine. To update
3614 that distribution, along with the Guix tools, you must run @command{guix
3615 pull}: the command downloads the latest Guix source code and package
3616 descriptions, and deploys it. Source code is downloaded from a
3617 @uref{https://git-scm.com, Git} repository, by default the official
3618 GNU@tie{}Guix repository, though this can be customized.
3620 On completion, @command{guix package} will use packages and package
3621 versions from this just-retrieved copy of Guix. Not only that, but all
3622 the Guix commands and Scheme modules will also be taken from that latest
3623 version. New @command{guix} sub-commands added by the update also
3626 Any user can update their Guix copy using @command{guix pull}, and the
3627 effect is limited to the user who ran @command{guix pull}. For
3628 instance, when user @code{root} runs @command{guix pull}, this has no
3629 effect on the version of Guix that user @code{alice} sees, and vice
3632 The result of running @command{guix pull} is a @dfn{profile} available
3633 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3634 make sure to add it to the beginning of your search path so that you use
3635 the latest version, and similarly for the Info manual
3636 (@pxref{Documentation}):
3639 export PATH="$HOME/.config/guix/current/bin:$PATH"
3640 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3643 The @code{--list-generations} or @code{-l} option lists past generations
3644 produced by @command{guix pull}, along with details about their provenance:
3648 Generation 1 Jun 10 2018 00:18:18
3650 repository URL: https://git.savannah.gnu.org/git/guix.git
3651 branch: origin/master
3652 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3654 Generation 2 Jun 11 2018 11:02:49
3656 repository URL: https://git.savannah.gnu.org/git/guix.git
3657 branch: origin/master
3658 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3659 2 new packages: keepalived, libnfnetlink
3660 6 packages upgraded: emacs-nix-mode@@2.0.4,
3661 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3662 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3664 Generation 3 Jun 13 2018 23:31:07 (current)
3666 repository URL: https://git.savannah.gnu.org/git/guix.git
3667 branch: origin/master
3668 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3669 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3670 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3673 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3674 describe the current status of Guix.
3676 This @code{~/.config/guix/current} profile works like any other profile
3677 created by @command{guix package} (@pxref{Invoking guix package}). That
3678 is, you can list generations, roll back to the previous
3679 generation---i.e., the previous Guix---and so on:
3682 $ guix package -p ~/.config/guix/current --roll-back
3683 switched from generation 3 to 2
3684 $ guix package -p ~/.config/guix/current --delete-generations=1
3685 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3688 The @command{guix pull} command is usually invoked with no arguments,
3689 but it supports the following options:
3692 @item --url=@var{url}
3693 @itemx --commit=@var{commit}
3694 @itemx --branch=@var{branch}
3695 Download code for the @code{guix} channel from the specified @var{url}, at the
3696 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3697 string), or @var{branch}.
3699 @cindex @file{channels.scm}, configuration file
3700 @cindex configuration file for channels
3701 These options are provided for convenience, but you can also specify your
3702 configuration in the @file{~/.config/guix/channels.scm} file or using the
3703 @option{--channels} option (see below).
3705 @item --channels=@var{file}
3706 @itemx -C @var{file}
3707 Read the list of channels from @var{file} instead of
3708 @file{~/.config/guix/channels.scm}. @var{file} must contain Scheme code that
3709 evaluates to a list of channel objects. @xref{Channels}, for more
3714 Display the list of packages added or upgraded since the previous generation.
3716 This is the same information as displayed upon @command{guix pull} completion,
3717 but without ellipses; it is also similar to the output of @command{guix pull
3718 -l} for the last generation (see below).
3720 @item --list-generations[=@var{pattern}]
3721 @itemx -l [@var{pattern}]
3722 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3723 is provided, the subset of generations that match @var{pattern}.
3724 The syntax of @var{pattern} is the same as with @code{guix package
3725 --list-generations} (@pxref{Invoking guix package}).
3727 @xref{Invoking guix describe}, for a way to display information about the
3728 current generation only.
3730 @item --profile=@var{profile}
3731 @itemx -p @var{profile}
3732 Use @var{profile} instead of @file{~/.config/guix/current}.
3736 Show which channel commit(s) would be used and what would be built or
3737 substituted but do not actually do it.
3739 @item --system=@var{system}
3740 @itemx -s @var{system}
3741 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3742 the system type of the build host.
3745 Produce verbose output, writing build logs to the standard error output.
3748 Use the bootstrap Guile to build the latest Guix. This option is only
3749 useful to Guix developers.
3752 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3753 repository and branch to pull from, as well as @emph{additional} repositories
3754 containing package modules that should be deployed. @xref{Channels}, for more
3757 In addition, @command{guix pull} supports all the common build options
3758 (@pxref{Common Build Options}).
3764 @cindex @file{channels.scm}, configuration file
3765 @cindex configuration file for channels
3766 @cindex @command{guix pull}, configuration file
3767 @cindex configuration of @command{guix pull}
3768 Guix and its package collection are updated by running @command{guix pull}
3769 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3770 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3771 customized by defining @dfn{channels} in the
3772 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3773 of a Git repository to be deployed, and @command{guix pull} can be instructed
3774 to pull from one or more channels. In other words, channels can be used to
3775 @emph{customize} and to @emph{extend} Guix, as we will see below.
3777 @subsection Using a Custom Guix Channel
3779 The channel called @code{guix} specifies where Guix itself---its command-line
3780 tools as well as its package collection---should be downloaded. For instance,
3781 suppose you want to update from your own copy of the Guix repository at
3782 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3783 write in @code{~/.config/guix/channels.scm} this specification:
3786 ;; Tell 'guix pull' to use my own repo.
3789 (url "https://example.org/my-guix.git")
3790 (branch "super-hacks")))
3794 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3795 branch of the repository at @code{example.org}.
3797 @subsection Specifying Additional Channels
3799 @cindex extending the package collection (channels)
3800 @cindex personal packages (channels)
3801 @cindex channels, for personal packages
3802 You can also specify @emph{additional channels} to pull from. Let's say you
3803 have a bunch of custom package variants or personal packages that you think
3804 would make little sense to contribute to the Guix project, but would like to
3805 have these packages transparently available to you at the command line. You
3806 would first write modules containing those package definitions (@pxref{Package
3807 Modules}), maintain them in a Git repository, and then you and anyone else can
3808 use it as an additional channel to get packages from. Neat, no?
3810 @c What follows stems from discussions at
3811 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3812 @c earlier discussions on guix-devel@gnu.org.
3814 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3815 publish your personal channel to the world, we would like to share a few words
3820 Before publishing a channel, please consider contributing your package
3821 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3822 to free software of all sorts, and packages in Guix proper are readily
3823 available to all Guix users and benefit from the project's quality assurance
3827 When you maintain package definitions outside Guix, we, Guix developers,
3828 consider that @emph{the compatibility burden is on you}. Remember that
3829 package modules and package definitions are just Scheme code that uses various
3830 programming interfaces (APIs). We want to remain free to change these APIs to
3831 keep improving Guix, possibly in ways that break your channel. We never
3832 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
3836 Corollary: if you're using an external channel and that channel breaks, please
3837 @emph{report the issue to the channel authors}, not to the Guix project.
3840 You've been warned! Having said this, we believe external channels are a
3841 practical way to exert your freedom to augment Guix' package collection and to
3842 share your improvements, which are basic tenets of
3843 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
3844 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
3847 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
3848 @command{guix pull} to pull from it @emph{in addition} to the default Guix
3851 @vindex %default-channels
3853 ;; Add my personal packages to those Guix provides.
3855 (name 'my-personal-packages)
3856 (url "https://example.org/personal-packages.git"))
3861 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
3862 add a channel the list of channels that the variable @code{%default-channels}
3863 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
3864 Manual}). With this file in place, @command{guix pull} builds not only Guix
3865 but also the package modules from your own repository. The result in
3866 @file{~/.config/guix/current} is the union of Guix with your own package
3870 $ guix pull --list-generations
3872 Generation 19 Aug 27 2018 16:20:48
3874 repository URL: https://git.savannah.gnu.org/git/guix.git
3876 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
3877 my-personal-packages dd3df5e
3878 repository URL: https://example.org/personal-packages.git
3880 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
3881 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
3882 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
3886 The output of @command{guix pull} above shows that Generation@tie{}19 includes
3887 both Guix and packages from the @code{my-personal-packages} channel. Among
3888 the new and upgraded packages that are listed, some like @code{my-gimp} and
3889 @code{my-emacs-with-cool-features} might come from
3890 @code{my-personal-packages}, while others come from the Guix default channel.
3892 To create a channel, create a Git repository containing your own package
3893 modules and make it available. The repository can contain anything, but a
3894 useful channel will contain Guile modules that export packages. Once you
3895 start using a channel, Guix will behave as if the root directory of that
3896 channel's Git repository has been added to the Guile load path (@pxref{Load
3897 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
3898 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
3899 module, then the module will be available under the name @code{(my-packages
3900 my-tools)}, and you will be able to use it like any other module
3901 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
3903 @cindex dependencies, channels
3904 @cindex meta-data, channels
3905 @subsection Declaring Channel Dependencies
3907 Channel authors may decide to augment a package collection provided by other
3908 channels. They can declare their channel to be dependent on other channels in
3909 a meta-data file @file{.guix-channel}, which is to be placed in the root of
3910 the channel repository.
3912 The meta-data file should contain a simple S-expression like this:
3919 (name some-collection)
3920 (url "https://example.org/first-collection.git"))
3922 (name some-other-collection)
3923 (url "https://example.org/second-collection.git")
3924 (branch "testing"))))
3927 In the above example this channel is declared to depend on two other channels,
3928 which will both be fetched automatically. The modules provided by the channel
3929 will be compiled in an environment where the modules of all these declared
3930 channels are available.
3932 For the sake of reliability and maintainability, you should avoid dependencies
3933 on channels that you don't control, and you should aim to keep the number of
3934 dependencies to a minimum.
3936 @cindex subdirectory, channels
3937 @subsection Package Modules in a Sub-directory
3939 As a channel author, you may want to keep your channel modules in a
3940 sub-directory. If your modules are in the sub-directory @file{guix}, you must
3941 add a meta-data file @file{.guix-channel} that contains:
3949 @subsection Replicating Guix
3951 @cindex pinning, channels
3952 @cindex replicating Guix
3953 @cindex reproducibility, of Guix
3954 The @command{guix pull --list-generations} output above shows precisely which
3955 commits were used to build this instance of Guix. We can thus replicate it,
3956 say, on another machine, by providing a channel specification in
3957 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
3960 ;; Deploy specific commits of my channels of interest.
3963 (url "https://git.savannah.gnu.org/git/guix.git")
3964 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
3966 (name 'my-personal-packages)
3967 (url "https://example.org/personal-packages.git")
3968 (branch "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
3971 The @command{guix describe --format=channels} command can even generate this
3972 list of channels directly (@pxref{Invoking guix describe}).
3974 At this point the two machines run the @emph{exact same Guix}, with access to
3975 the @emph{exact same packages}. The output of @command{guix build gimp} on
3976 one machine will be exactly the same, bit for bit, as the output of the same
3977 command on the other machine. It also means both machines have access to all
3978 the source code of Guix and, transitively, to all the source code of every
3981 This gives you super powers, allowing you to track the provenance of binary
3982 artifacts with very fine grain, and to reproduce software environments at
3983 will---some sort of ``meta reproducibility'' capabilities, if you will.
3984 @xref{Inferiors}, for another way to take advantage of these super powers.
3989 @c TODO: Remove this once we're more confident about API stability.
3991 The functionality described here is a ``technology preview'' as of version
3992 @value{VERSION}. As such, the interface is subject to change.
3996 @cindex composition of Guix revisions
3997 Sometimes you might need to mix packages from the revision of Guix you're
3998 currently running with packages available in a different revision of Guix.
3999 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4000 revisions in arbitrary ways.
4002 @cindex inferior packages
4003 Technically, an ``inferior'' is essentially a separate Guix process connected
4004 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4005 @code{(guix inferior)} module allows you to create inferiors and to
4006 communicate with them. It also provides a high-level interface to browse and
4007 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4009 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4010 to interact with a separate revision of Guix. For example, let's assume you
4011 want to install in your profile the current @code{guile} package, along with
4012 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4013 because the newer @code{guile-json} has an incompatible API and you want to
4014 run your code against the old API@. To do that, you could write a manifest for
4015 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4016 manifest, you would create an inferior for that old Guix revision you care
4017 about, and you would look up the @code{guile-json} package in the inferior:
4020 (use-modules (guix inferior) (guix channels)
4021 (srfi srfi-1)) ;for 'first'
4024 ;; This is the old revision from which we want to
4025 ;; extract guile-json.
4028 (url "https://git.savannah.gnu.org/git/guix.git")
4030 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4033 ;; An inferior representing the above revision.
4034 (inferior-for-channels channels))
4036 ;; Now create a manifest with the current "guile" package
4037 ;; and the old "guile-json" package.
4039 (list (first (lookup-inferior-packages inferior "guile-json"))
4040 (specification->package "guile")))
4043 On its first run, @command{guix package --manifest} might have to build the
4044 channel you specified before it can create the inferior; subsequent runs will
4045 be much faster because the Guix revision will be cached.
4047 The @code{(guix inferior)} module provides the following procedures to open an
4050 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4051 [#:cache-directory] [#:ttl]
4052 Return an inferior for @var{channels}, a list of channels. Use the cache at
4053 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4054 This procedure opens a new connection to the build daemon.
4056 As a side effect, this procedure may build or substitute binaries for
4057 @var{channels}, which can take time.
4060 @deffn {Scheme Procedure} open-inferior @var{directory} @
4061 [#:command "bin/guix"]
4062 Open the inferior Guix in @var{directory}, running
4063 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4064 the inferior could not be launched.
4067 @cindex inferior packages
4068 The procedures listed below allow you to obtain and manipulate inferior
4071 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4072 Return the list of packages known to @var{inferior}.
4075 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4077 Return the sorted list of inferior packages matching @var{name} in
4078 @var{inferior}, with highest version numbers first. If @var{version} is true,
4079 return only packages with a version number prefixed by @var{version}.
4082 @deffn {Scheme Procedure} inferior-package? @var{obj}
4083 Return true if @var{obj} is an inferior package.
4086 @deffn {Scheme Procedure} inferior-package-name @var{package}
4087 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4088 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4089 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4090 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4091 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4092 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4093 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4094 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4095 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4096 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4097 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4098 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4099 These procedures are the counterpart of package record accessors
4100 (@pxref{package Reference}). Most of them work by querying the inferior
4101 @var{package} comes from, so the inferior must still be live when you call
4105 Inferior packages can be used transparently like any other package or
4106 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4107 transparently handled by the @code{packages->manifest} procedure, which is
4108 commonly use in manifests (@pxref{Invoking guix package, the
4109 @option{--manifest} option of @command{guix package}}). Thus you can insert
4110 an inferior package pretty much anywhere you would insert a regular package:
4111 in manifests, in the @code{packages} field of your @code{operating-system}
4112 declaration, and so on.
4114 @node Invoking guix describe
4115 @section Invoking @command{guix describe}
4117 @cindex reproducibility
4118 @cindex replicating Guix
4119 Often you may want to answer questions like: ``Which revision of Guix am I
4120 using?'' or ``Which channels am I using?'' This is useful information in many
4121 situations: if you want to @emph{replicate} an environment on a different
4122 machine or user account, if you want to report a bug or to determine what
4123 change in the channels you are using caused it, or if you want to record your
4124 system state for reproducibility purposes. The @command{guix describe}
4125 command answers these questions.
4127 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4128 displays the channel(s) that it was built from, including their repository URL
4129 and commit IDs (@pxref{Channels}):
4133 Generation 10 Sep 03 2018 17:32:44 (current)
4135 repository URL: https://git.savannah.gnu.org/git/guix.git
4137 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4140 If you're familiar with the Git version control system, this is similar in
4141 spirit to @command{git describe}; the output is also similar to that of
4142 @command{guix pull --list-generations}, but limited to the current generation
4143 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4144 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4145 information is all it takes to describe the revision of Guix you're using, and
4146 also to replicate it.
4148 To make it easier to replicate Guix, @command{guix describe} can also be asked
4149 to return a list of channels instead of the human-readable description above:
4152 $ guix describe -f channels
4155 (url "https://git.savannah.gnu.org/git/guix.git")
4157 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4161 You can save this to a file and feed it to @command{guix pull -C} on some
4162 other machine or at a later point in time, which will instantiate @emph{this
4163 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4164 From there on, since you're able to deploy the same revision of Guix, you can
4165 just as well @emph{replicate a complete software environment}. We humbly
4166 think that this is @emph{awesome}, and we hope you'll like it too!
4168 The details of the options supported by @command{guix describe} are as
4172 @item --format=@var{format}
4173 @itemx -f @var{format}
4174 Produce output in the specified @var{format}, one of:
4178 produce human-readable output;
4180 produce a list of channel specifications that can be passed to @command{guix
4181 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4185 produce a list of channel specifications in JSON format;
4187 produce a list of channel specifications in Recutils format.
4190 @item --profile=@var{profile}
4191 @itemx -p @var{profile}
4192 Display information about @var{profile}.
4195 @node Invoking guix archive
4196 @section Invoking @command{guix archive}
4198 @cindex @command{guix archive}
4200 The @command{guix archive} command allows users to @dfn{export} files
4201 from the store into a single archive, and to later @dfn{import} them on
4202 a machine that runs Guix.
4203 In particular, it allows store files to be transferred from one machine
4204 to the store on another machine.
4207 If you're looking for a way to produce archives in a format suitable for
4208 tools other than Guix, @pxref{Invoking guix pack}.
4211 @cindex exporting store items
4212 To export store files as an archive to standard output, run:
4215 guix archive --export @var{options} @var{specifications}...
4218 @var{specifications} may be either store file names or package
4219 specifications, as for @command{guix package} (@pxref{Invoking guix
4220 package}). For instance, the following command creates an archive
4221 containing the @code{gui} output of the @code{git} package and the main
4222 output of @code{emacs}:
4225 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4228 If the specified packages are not built yet, @command{guix archive}
4229 automatically builds them. The build process may be controlled with the
4230 common build options (@pxref{Common Build Options}).
4232 To transfer the @code{emacs} package to a machine connected over SSH,
4236 guix archive --export -r emacs | ssh the-machine guix archive --import
4240 Similarly, a complete user profile may be transferred from one machine
4241 to another like this:
4244 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4245 ssh the-machine guix archive --import
4249 However, note that, in both examples, all of @code{emacs} and the
4250 profile as well as all of their dependencies are transferred (due to
4251 @code{-r}), regardless of what is already available in the store on the
4252 target machine. The @code{--missing} option can help figure out which
4253 items are missing from the target store. The @command{guix copy}
4254 command simplifies and optimizes this whole process, so this is probably
4255 what you should use in this case (@pxref{Invoking guix copy}).
4257 @cindex nar, archive format
4258 @cindex normalized archive (nar)
4259 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4260 comparable in spirit to `tar', but with differences
4261 that make it more appropriate for our purposes. First, rather than
4262 recording all Unix metadata for each file, the nar format only mentions
4263 the file type (regular, directory, or symbolic link); Unix permissions
4264 and owner/group are dismissed. Second, the order in which directory
4265 entries are stored always follows the order of file names according to
4266 the C locale collation order. This makes archive production fully
4269 When exporting, the daemon digitally signs the contents of the archive,
4270 and that digital signature is appended. When importing, the daemon
4271 verifies the signature and rejects the import in case of an invalid
4272 signature or if the signing key is not authorized.
4273 @c FIXME: Add xref to daemon doc about signatures.
4275 The main options are:
4279 Export the specified store files or packages (see below.) Write the
4280 resulting archive to the standard output.
4282 Dependencies are @emph{not} included in the output, unless
4283 @code{--recursive} is passed.
4287 When combined with @code{--export}, this instructs @command{guix
4288 archive} to include dependencies of the given items in the archive.
4289 Thus, the resulting archive is self-contained: it contains the closure
4290 of the exported store items.
4293 Read an archive from the standard input, and import the files listed
4294 therein into the store. Abort if the archive has an invalid digital
4295 signature, or if it is signed by a public key not among the authorized
4296 keys (see @code{--authorize} below.)
4299 Read a list of store file names from the standard input, one per line,
4300 and write on the standard output the subset of these files missing from
4303 @item --generate-key[=@var{parameters}]
4304 @cindex signing, archives
4305 Generate a new key pair for the daemon. This is a prerequisite before
4306 archives can be exported with @code{--export}. Note that this operation
4307 usually takes time, because it needs to gather enough entropy to
4308 generate the key pair.
4310 The generated key pair is typically stored under @file{/etc/guix}, in
4311 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4312 key, which must be kept secret.) When @var{parameters} is omitted,
4313 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4314 versions before 1.6.0, it is a 4096-bit RSA key.
4315 Alternatively, @var{parameters} can specify
4316 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4317 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4318 Libgcrypt Reference Manual}).
4321 @cindex authorizing, archives
4322 Authorize imports signed by the public key passed on standard input.
4323 The public key must be in ``s-expression advanced format''---i.e., the
4324 same format as the @file{signing-key.pub} file.
4326 The list of authorized keys is kept in the human-editable file
4327 @file{/etc/guix/acl}. The file contains
4328 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4329 s-expressions''} and is structured as an access-control list in the
4330 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4333 @item --extract=@var{directory}
4334 @itemx -x @var{directory}
4335 Read a single-item archive as served by substitute servers
4336 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4337 low-level operation needed in only very narrow use cases; see below.
4339 For example, the following command extracts the substitute for Emacs
4340 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4344 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-emacs-24.5 \
4345 | bunzip2 | guix archive -x /tmp/emacs
4348 Single-item archives are different from multiple-item archives produced
4349 by @command{guix archive --export}; they contain a single store item,
4350 and they do @emph{not} embed a signature. Thus this operation does
4351 @emph{no} signature verification and its output should be considered
4354 The primary purpose of this operation is to facilitate inspection of
4355 archive contents coming from possibly untrusted substitute servers.
4360 @c *********************************************************************
4362 @chapter Development
4364 @cindex software development
4365 If you are a software developer, Guix provides tools that you should find
4366 helpful---independently of the language you're developing in. This is what
4367 this chapter is about.
4369 The @command{guix environment} command provides a convenient way to set up
4370 @dfn{development environments} containing all the dependencies and tools
4371 necessary to work on the software package of your choice. The @command{guix
4372 pack} command allows you to create @dfn{application bundles} that can be
4373 easily distributed to users who do not run Guix.
4376 * Invoking guix environment:: Setting up development environments.
4377 * Invoking guix pack:: Creating software bundles.
4380 @node Invoking guix environment
4381 @section Invoking @command{guix environment}
4383 @cindex reproducible build environments
4384 @cindex development environments
4385 @cindex @command{guix environment}
4386 @cindex environment, package build environment
4387 The purpose of @command{guix environment} is to assist hackers in
4388 creating reproducible development environments without polluting their
4389 package profile. The @command{guix environment} tool takes one or more
4390 packages, builds all of their inputs, and creates a shell
4391 environment to use them.
4393 The general syntax is:
4396 guix environment @var{options} @var{package}@dots{}
4399 The following example spawns a new shell set up for the development of
4403 guix environment guile
4406 If the needed dependencies are not built yet, @command{guix environment}
4407 automatically builds them. The environment of the new shell is an augmented
4408 version of the environment that @command{guix environment} was run in.
4409 It contains the necessary search paths for building the given package
4410 added to the existing environment variables. To create a ``pure''
4411 environment, in which the original environment variables have been unset,
4412 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4413 environment variables such as @code{PATH} in their @file{~/.bashrc}
4414 file. As a consequence, when @code{guix environment} launches it, Bash
4415 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4416 environment variables. It is an error to define such environment
4417 variables in @file{.bashrc}; instead, they should be defined in
4418 @file{.bash_profile}, which is sourced only by log-in shells.
4419 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4420 details on Bash start-up files.}.
4422 @vindex GUIX_ENVIRONMENT
4423 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4424 variable in the shell it spawns; its value is the file name of the
4425 profile of this environment. This allows users to, say, define a
4426 specific prompt for development environments in their @file{.bashrc}
4427 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4430 if [ -n "$GUIX_ENVIRONMENT" ]
4432 export PS1="\u@@\h \w [dev]\$ "
4437 ...@: or to browse the profile:
4440 $ ls "$GUIX_ENVIRONMENT/bin"
4443 Additionally, more than one package may be specified, in which case the
4444 union of the inputs for the given packages are used. For example, the
4445 command below spawns a shell where all of the dependencies of both Guile
4446 and Emacs are available:
4449 guix environment guile emacs
4452 Sometimes an interactive shell session is not desired. An arbitrary
4453 command may be invoked by placing the @code{--} token to separate the
4454 command from the rest of the arguments:
4457 guix environment guile -- make -j4
4460 In other situations, it is more convenient to specify the list of
4461 packages needed in the environment. For example, the following command
4462 runs @command{python} from an environment containing Python@tie{}2.7 and
4466 guix environment --ad-hoc python2-numpy python-2.7 -- python
4469 Furthermore, one might want the dependencies of a package and also some
4470 additional packages that are not build-time or runtime dependencies, but
4471 are useful when developing nonetheless. Because of this, the
4472 @code{--ad-hoc} flag is positional. Packages appearing before
4473 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4474 added to the environment. Packages appearing after are interpreted as
4475 packages that will be added to the environment directly. For example,
4476 the following command creates a Guix development environment that
4477 additionally includes Git and strace:
4480 guix environment guix --ad-hoc git strace
4483 Sometimes it is desirable to isolate the environment as much as
4484 possible, for maximal purity and reproducibility. In particular, when
4485 using Guix on a host distro that is not Guix System, it is desirable to
4486 prevent access to @file{/usr/bin} and other system-wide resources from
4487 the development environment. For example, the following command spawns
4488 a Guile REPL in a ``container'' where only the store and the current
4489 working directory are mounted:
4492 guix environment --ad-hoc --container guile -- guile
4496 The @code{--container} option requires Linux-libre 3.19 or newer.
4499 The available options are summarized below.
4502 @item --root=@var{file}
4503 @itemx -r @var{file}
4504 @cindex persistent environment
4505 @cindex garbage collector root, for environments
4506 Make @var{file} a symlink to the profile for this environment, and
4507 register it as a garbage collector root.
4509 This is useful if you want to protect your environment from garbage
4510 collection, to make it ``persistent''.
4512 When this option is omitted, the environment is protected from garbage
4513 collection only for the duration of the @command{guix environment}
4514 session. This means that next time you recreate the same environment,
4515 you could have to rebuild or re-download packages. @xref{Invoking guix
4516 gc}, for more on GC roots.
4518 @item --expression=@var{expr}
4519 @itemx -e @var{expr}
4520 Create an environment for the package or list of packages that
4521 @var{expr} evaluates to.
4523 For example, running:
4526 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4529 starts a shell with the environment for this specific variant of the
4535 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4538 starts a shell with all the base system packages available.
4540 The above commands only use the default output of the given packages.
4541 To select other outputs, two element tuples can be specified:
4544 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4547 @item --load=@var{file}
4548 @itemx -l @var{file}
4549 Create an environment for the package or list of packages that the code
4550 within @var{file} evaluates to.
4552 As an example, @var{file} might contain a definition like this
4553 (@pxref{Defining Packages}):
4556 @verbatiminclude environment-gdb.scm
4559 @item --manifest=@var{file}
4560 @itemx -m @var{file}
4561 Create an environment for the packages contained in the manifest object
4562 returned by the Scheme code in @var{file}.
4564 This is similar to the same-named option in @command{guix package}
4565 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4569 Include all specified packages in the resulting environment, as if an
4570 @i{ad hoc} package were defined with them as inputs. This option is
4571 useful for quickly creating an environment without having to write a
4572 package expression to contain the desired inputs.
4574 For instance, the command:
4577 guix environment --ad-hoc guile guile-sdl -- guile
4580 runs @command{guile} in an environment where Guile and Guile-SDL are
4583 Note that this example implicitly asks for the default output of
4584 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4585 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4586 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4588 This option may be composed with the default behavior of @command{guix
4589 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4590 as packages whose dependencies will be added to the environment, the
4591 default behavior. Packages appearing after are interpreted as packages
4592 that will be added to the environment directly.
4595 Unset existing environment variables when building the new environment, except
4596 those specified with @option{--preserve} (see below.) This has the effect of
4597 creating an environment in which search paths only contain package inputs.
4599 @item --preserve=@var{regexp}
4600 @itemx -E @var{regexp}
4601 When used alongside @option{--pure}, preserve the environment variables
4602 matching @var{regexp}---in other words, put them on a ``white list'' of
4603 environment variables that must be preserved. This option can be repeated
4607 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4611 This example runs @command{mpirun} in a context where the only environment
4612 variables defined are @code{PATH}, environment variables whose name starts
4613 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4616 @item --search-paths
4617 Display the environment variable definitions that make up the
4620 @item --system=@var{system}
4621 @itemx -s @var{system}
4622 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4627 Run @var{command} within an isolated container. The current working
4628 directory outside the container is mapped inside the container.
4629 Additionally, unless overridden with @code{--user}, a dummy home
4630 directory is created that matches the current user's home directory, and
4631 @file{/etc/passwd} is configured accordingly.
4633 The spawned process runs as the current user outside the container. Inside
4634 the container, it has the same UID and GID as the current user, unless
4635 @option{--user} is passed (see below.)
4639 For containers, share the network namespace with the host system.
4640 Containers created without this flag only have access to the loopback
4643 @item --link-profile
4645 For containers, link the environment profile to
4646 @file{~/.guix-profile} within the container. This is equivalent to
4647 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4648 within the container. Linking will fail and abort the environment if
4649 the directory already exists, which will certainly be the case if
4650 @command{guix environment} was invoked in the user's home directory.
4652 Certain packages are configured to look in
4653 @code{~/.guix-profile} for configuration files and data;@footnote{For
4654 example, the @code{fontconfig} package inspects
4655 @file{~/.guix-profile/share/fonts} for additional fonts.}
4656 @code{--link-profile} allows these programs to behave as expected within
4659 @item --user=@var{user}
4660 @itemx -u @var{user}
4661 For containers, use the username @var{user} in place of the current
4662 user. The generated @file{/etc/passwd} entry within the container will
4663 contain the name @var{user}, the home directory will be
4664 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4665 the UID and GID inside the container are 1000. @var{user}
4666 need not exist on the system.
4668 Additionally, any shared or exposed path (see @code{--share} and
4669 @code{--expose} respectively) whose target is within the current user's
4670 home directory will be remapped relative to @file{/home/USER}; this
4671 includes the automatic mapping of the current working directory.
4674 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4676 guix environment --container --user=foo \
4677 --expose=$HOME/test \
4678 --expose=/tmp/target=$HOME/target
4681 While this will limit the leaking of user identity through home paths
4682 and each of the user fields, this is only one useful component of a
4683 broader privacy/anonymity solution---not one in and of itself.
4686 For containers, the default behavior is to share the current working
4687 directory with the isolated container and immediately change to that
4688 directory within the container. If this is undesirable, @code{--no-cwd}
4689 will cause the current working directory to @emph{not} be automatically
4690 shared and will change to the user's home directory within the container
4691 instead. See also @code{--user}.
4693 @item --expose=@var{source}[=@var{target}]
4694 For containers, expose the file system @var{source} from the host system
4695 as the read-only file system @var{target} within the container. If
4696 @var{target} is not specified, @var{source} is used as the target mount
4697 point in the container.
4699 The example below spawns a Guile REPL in a container in which the user's
4700 home directory is accessible read-only via the @file{/exchange}
4704 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
4707 @item --share=@var{source}[=@var{target}]
4708 For containers, share the file system @var{source} from the host system
4709 as the writable file system @var{target} within the container. If
4710 @var{target} is not specified, @var{source} is used as the target mount
4711 point in the container.
4713 The example below spawns a Guile REPL in a container in which the user's
4714 home directory is accessible for both reading and writing via the
4715 @file{/exchange} directory:
4718 guix environment --container --share=$HOME=/exchange --ad-hoc guile -- guile
4722 @command{guix environment}
4723 also supports all of the common build options that @command{guix
4724 build} supports (@pxref{Common Build Options}) as well as package
4725 transformation options (@pxref{Package Transformation Options}).
4727 @node Invoking guix pack
4728 @section Invoking @command{guix pack}
4730 Occasionally you want to pass software to people who are not (yet!)
4731 lucky enough to be using Guix. You'd tell them to run @command{guix
4732 package -i @var{something}}, but that's not possible in this case. This
4733 is where @command{guix pack} comes in.
4736 If you are looking for ways to exchange binaries among machines that
4737 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
4738 publish}, and @ref{Invoking guix archive}.
4743 @cindex application bundle
4744 @cindex software bundle
4745 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
4746 @dfn{software bundle}: it creates a tarball or some other archive
4747 containing the binaries of the software you're interested in, and all
4748 its dependencies. The resulting archive can be used on any machine that
4749 does not have Guix, and people can run the exact same binaries as those
4750 you have with Guix. The pack itself is created in a bit-reproducible
4751 fashion, so anyone can verify that it really contains the build results
4752 that you pretend to be shipping.
4754 For example, to create a bundle containing Guile, Emacs, Geiser, and all
4755 their dependencies, you can run:
4758 $ guix pack guile emacs geiser
4760 /gnu/store/@dots{}-pack.tar.gz
4763 The result here is a tarball containing a @file{/gnu/store} directory
4764 with all the relevant packages. The resulting tarball contains a
4765 @dfn{profile} with the three packages of interest; the profile is the
4766 same as would be created by @command{guix package -i}. It is this
4767 mechanism that is used to create Guix's own standalone binary tarball
4768 (@pxref{Binary Installation}).
4770 Users of this pack would have to run
4771 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
4772 find inconvenient. To work around it, you can create, say, a
4773 @file{/opt/gnu/bin} symlink to the profile:
4776 guix pack -S /opt/gnu/bin=bin guile emacs geiser
4780 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
4782 @cindex relocatable binaries, with @command{guix pack}
4783 What if the recipient of your pack does not have root privileges on
4784 their machine, and thus cannot unpack it in the root file system? In
4785 that case, you will want to use the @code{--relocatable} option (see
4786 below). This option produces @dfn{relocatable binaries}, meaning they
4787 they can be placed anywhere in the file system hierarchy: in the example
4788 above, users can unpack your tarball in their home directory and
4789 directly run @file{./opt/gnu/bin/guile}.
4791 @cindex Docker, build an image with guix pack
4792 Alternatively, you can produce a pack in the Docker image format using
4793 the following command:
4796 guix pack -f docker guile emacs geiser
4800 The result is a tarball that can be passed to the @command{docker load}
4802 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
4803 documentation} for more information.
4805 @cindex Singularity, build an image with guix pack
4806 @cindex SquashFS, build an image with guix pack
4807 Yet another option is to produce a SquashFS image with the following
4811 guix pack -f squashfs guile emacs geiser
4815 The result is a SquashFS file system image that can either be mounted or
4816 directly be used as a file system container image with the
4817 @uref{https://singularity.lbl.gov, Singularity container execution
4818 environment}, using commands like @command{singularity shell} or
4819 @command{singularity exec}.
4821 Several command-line options allow you to customize your pack:
4824 @item --format=@var{format}
4825 @itemx -f @var{format}
4826 Produce a pack in the given @var{format}.
4828 The available formats are:
4832 This is the default format. It produces a tarball containing all the
4833 specified binaries and symlinks.
4836 This produces a tarball that follows the
4837 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
4838 Docker Image Specification}.
4841 This produces a SquashFS image containing all the specified binaries and
4842 symlinks, as well as empty mount points for virtual file systems like
4846 @cindex relocatable binaries
4849 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
4850 anywhere in the file system hierarchy and run from there.
4852 When this option is passed once, the resulting binaries require support for
4853 @dfn{user namespaces} in the kernel Linux; when passed
4854 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
4855 PRoot support, can be thought of as the abbreviation of ``Really
4856 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
4857 if user namespaces are unavailable, and essentially work anywhere---see below
4858 for the implications.
4860 For example, if you create a pack containing Bash with:
4863 guix pack -RR -S /mybin=bin bash
4867 ...@: you can copy that pack to a machine that lacks Guix, and from your
4868 home directory as a normal user, run:
4876 In that shell, if you type @code{ls /gnu/store}, you'll notice that
4877 @file{/gnu/store} shows up and contains all the dependencies of
4878 @code{bash}, even though the machine actually lacks @file{/gnu/store}
4879 altogether! That is probably the simplest way to deploy Guix-built
4880 software on a non-Guix machine.
4883 By default, relocatable binaries rely on the @dfn{user namespace} feature of
4884 the kernel Linux, which allows unprivileged users to mount or change root.
4885 Old versions of Linux did not support it, and some GNU/Linux distributions
4888 To produce relocatable binaries that work even in the absence of user
4889 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
4890 case, binaries will try user namespace support and fall back to PRoot if user
4891 namespaces are not supported.
4893 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
4894 support for file system virtualization. It achieves that by using the
4895 @code{ptrace} system call on the running program. This approach has the
4896 advantage to work without requiring special kernel support, but it incurs
4897 run-time overhead every time a system call is made.
4900 @cindex entry point, for Docker images
4901 @item --entry-point=@var{command}
4902 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
4903 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
4904 support it. @var{command} must be relative to the profile contained in the
4907 The entry point specifies the command that tools like @code{docker run} or
4908 @code{singularity run} automatically start by default. For example, you can
4912 guix pack -f docker --entry-point=bin/guile guile
4915 The resulting pack can easily be loaded and @code{docker run} with no extra
4916 arguments will spawn @code{bin/guile}:
4919 docker load -i pack.tar.gz
4920 docker run @var{image-id}
4923 @item --expression=@var{expr}
4924 @itemx -e @var{expr}
4925 Consider the package @var{expr} evaluates to.
4927 This has the same purpose as the same-named option in @command{guix
4928 build} (@pxref{Additional Build Options, @code{--expression} in
4929 @command{guix build}}).
4931 @item --manifest=@var{file}
4932 @itemx -m @var{file}
4933 Use the packages contained in the manifest object returned by the Scheme
4936 This has a similar purpose as the same-named option in @command{guix
4937 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
4938 same manifest files. It allows you to define a collection of packages
4939 once and use it both for creating profiles and for creating archives
4940 for use on machines that do not have Guix installed. Note that you can
4941 specify @emph{either} a manifest file @emph{or} a list of packages,
4944 @item --system=@var{system}
4945 @itemx -s @var{system}
4946 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4947 the system type of the build host.
4949 @item --target=@var{triplet}
4950 @cindex cross-compilation
4951 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
4952 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
4953 configuration triplets,, autoconf, Autoconf}).
4955 @item --compression=@var{tool}
4956 @itemx -C @var{tool}
4957 Compress the resulting tarball using @var{tool}---one of @code{gzip},
4958 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
4960 @item --symlink=@var{spec}
4961 @itemx -S @var{spec}
4962 Add the symlinks specified by @var{spec} to the pack. This option can
4963 appear several times.
4965 @var{spec} has the form @code{@var{source}=@var{target}}, where
4966 @var{source} is the symlink that will be created and @var{target} is the
4969 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
4970 symlink pointing to the @file{bin} sub-directory of the profile.
4972 @item --save-provenance
4973 Save provenance information for the packages passed on the command line.
4974 Provenance information includes the URL and commit of the channels in use
4977 Provenance information is saved in the
4978 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
4979 usual package metadata---the name and version of each package, their
4980 propagated inputs, and so on. It is useful information to the recipient of
4981 the pack, who then knows how the pack was (supposedly) obtained.
4983 This option is not enabled by default because, like timestamps, provenance
4984 information contributes nothing to the build process. In other words, there
4985 is an infinity of channel URLs and commit IDs that can lead to the same pack.
4986 Recording such ``silent'' metadata in the output thus potentially breaks the
4987 source-to-binary bitwise reproducibility property.
4989 @item --root=@var{file}
4990 @itemx -r @var{file}
4991 @cindex garbage collector root, for packs
4992 Make @var{file} a symlink to the resulting pack, and register it as a garbage
4995 @item --localstatedir
4996 @itemx --profile-name=@var{name}
4997 Include the ``local state directory'', @file{/var/guix}, in the resulting
4998 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
4999 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5000 @file{~root/.guix-profile}.
5002 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5003 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5004 the pack means that the store is ``complete'' and manageable by Guix;
5005 not providing it pack means that the store is ``dead'': items cannot be
5006 added to it or removed from it after extraction of the pack.
5008 One use case for this is the Guix self-contained binary tarball
5009 (@pxref{Binary Installation}).
5012 Use the bootstrap binaries to build the pack. This option is only
5013 useful to Guix developers.
5016 In addition, @command{guix pack} supports all the common build options
5017 (@pxref{Common Build Options}) and all the package transformation
5018 options (@pxref{Package Transformation Options}).
5021 @c *********************************************************************
5022 @node Programming Interface
5023 @chapter Programming Interface
5025 GNU Guix provides several Scheme programming interfaces (APIs) to
5026 define, build, and query packages. The first interface allows users to
5027 write high-level package definitions. These definitions refer to
5028 familiar packaging concepts, such as the name and version of a package,
5029 its build system, and its dependencies. These definitions can then be
5030 turned into concrete build actions.
5032 Build actions are performed by the Guix daemon, on behalf of users. In a
5033 standard setup, the daemon has write access to the store---the
5034 @file{/gnu/store} directory---whereas users do not. The recommended
5035 setup also has the daemon perform builds in chroots, under a specific
5036 build users, to minimize interference with the rest of the system.
5039 Lower-level APIs are available to interact with the daemon and the
5040 store. To instruct the daemon to perform a build action, users actually
5041 provide it with a @dfn{derivation}. A derivation is a low-level
5042 representation of the build actions to be taken, and the environment in
5043 which they should occur---derivations are to package definitions what
5044 assembly is to C programs. The term ``derivation'' comes from the fact
5045 that build results @emph{derive} from them.
5047 This chapter describes all these APIs in turn, starting from high-level
5048 package definitions.
5051 * Package Modules:: Packages from the programmer's viewpoint.
5052 * Defining Packages:: Defining new packages.
5053 * Build Systems:: Specifying how packages are built.
5054 * The Store:: Manipulating the package store.
5055 * Derivations:: Low-level interface to package derivations.
5056 * The Store Monad:: Purely functional interface to the store.
5057 * G-Expressions:: Manipulating build expressions.
5058 * Invoking guix repl:: Fiddling with Guix interactively.
5061 @node Package Modules
5062 @section Package Modules
5064 From a programming viewpoint, the package definitions of the
5065 GNU distribution are provided by Guile modules in the @code{(gnu packages
5066 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5067 packages @dots{})} module name space are not necessarily ``GNU
5068 packages''. This module naming scheme follows the usual Guile module
5069 naming convention: @code{gnu} means that these modules are distributed
5070 as part of the GNU system, and @code{packages} identifies modules that
5071 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5072 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5073 module exports a variable named @code{emacs}, which is bound to a
5074 @code{<package>} object (@pxref{Defining Packages}).
5076 The @code{(gnu packages @dots{})} module name space is
5077 automatically scanned for packages by the command-line tools. For
5078 instance, when running @code{guix install emacs}, all the @code{(gnu
5079 packages @dots{})} modules are scanned until one that exports a package
5080 object whose name is @code{emacs} is found. This package search
5081 facility is implemented in the @code{(gnu packages)} module.
5083 @cindex customization, of packages
5084 @cindex package module search path
5085 Users can store package definitions in modules with different
5086 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5087 name and module name must match. For instance, the @code{(my-packages
5088 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5089 relative to the load path specified with @option{--load-path} or
5090 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5091 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5092 these package definitions visible to the user interfaces:
5096 By adding the directory containing your package modules to the search path
5097 with the @code{-L} flag of @command{guix package} and other commands
5098 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5099 environment variable described below.
5102 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5103 pulls from it. A channel is essentially a Git repository containing package
5104 modules. @xref{Channels}, for more information on how to define and use
5108 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5110 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5111 This is a colon-separated list of directories to search for additional
5112 package modules. Directories listed in this variable take precedence
5113 over the own modules of the distribution.
5116 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5117 each package is built based solely on other packages in the
5118 distribution. The root of this dependency graph is a small set of
5119 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5120 bootstrap)} module. For more information on bootstrapping,
5121 @pxref{Bootstrapping}.
5123 @node Defining Packages
5124 @section Defining Packages
5126 The high-level interface to package definitions is implemented in the
5127 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5128 example, the package definition, or @dfn{recipe}, for the GNU Hello
5129 package looks like this:
5132 (define-module (gnu packages hello)
5133 #:use-module (guix packages)
5134 #:use-module (guix download)
5135 #:use-module (guix build-system gnu)
5136 #:use-module (guix licenses)
5137 #:use-module (gnu packages gawk))
5139 (define-public hello
5145 (uri (string-append "mirror://gnu/hello/hello-" version
5149 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5150 (build-system gnu-build-system)
5151 (arguments '(#:configure-flags '("--enable-silent-rules")))
5152 (inputs `(("gawk" ,gawk)))
5153 (synopsis "Hello, GNU world: An example GNU package")
5154 (description "Guess what GNU Hello prints!")
5155 (home-page "https://www.gnu.org/software/hello/")
5160 Without being a Scheme expert, the reader may have guessed the meaning
5161 of the various fields here. This expression binds the variable
5162 @code{hello} to a @code{<package>} object, which is essentially a record
5163 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5164 This package object can be inspected using procedures found in the
5165 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5166 returns---surprise!---@code{"hello"}.
5168 With luck, you may be able to import part or all of the definition of
5169 the package you are interested in from another repository, using the
5170 @code{guix import} command (@pxref{Invoking guix import}).
5172 In the example above, @var{hello} is defined in a module of its own,
5173 @code{(gnu packages hello)}. Technically, this is not strictly
5174 necessary, but it is convenient to do so: all the packages defined in
5175 modules under @code{(gnu packages @dots{})} are automatically known to
5176 the command-line tools (@pxref{Package Modules}).
5178 There are a few points worth noting in the above package definition:
5182 The @code{source} field of the package is an @code{<origin>} object
5183 (@pxref{origin Reference}, for the complete reference).
5184 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5185 meaning that the source is a file to be downloaded over FTP or HTTP.
5187 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5188 the GNU mirrors defined in @code{(guix download)}.
5190 The @code{sha256} field specifies the expected SHA256 hash of the file
5191 being downloaded. It is mandatory, and allows Guix to check the
5192 integrity of the file. The @code{(base32 @dots{})} form introduces the
5193 base32 representation of the hash. You can obtain this information with
5194 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5195 hash} (@pxref{Invoking guix hash}).
5198 When needed, the @code{origin} form can also have a @code{patches} field
5199 listing patches to be applied, and a @code{snippet} field giving a
5200 Scheme expression to modify the source code.
5203 @cindex GNU Build System
5204 The @code{build-system} field specifies the procedure to build the
5205 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5206 represents the familiar GNU Build System, where packages may be
5207 configured, built, and installed with the usual @code{./configure &&
5208 make && make check && make install} command sequence.
5211 The @code{arguments} field specifies options for the build system
5212 (@pxref{Build Systems}). Here it is interpreted by
5213 @var{gnu-build-system} as a request run @file{configure} with the
5214 @code{--enable-silent-rules} flag.
5220 What about these quote (@code{'}) characters? They are Scheme syntax to
5221 introduce a literal list; @code{'} is synonymous with @code{quote}.
5222 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5223 for details. Here the value of the @code{arguments} field is a list of
5224 arguments passed to the build system down the road, as with @code{apply}
5225 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5228 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5229 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5230 @code{#:configure-flags} is a keyword used to pass a keyword argument
5231 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5235 The @code{inputs} field specifies inputs to the build process---i.e.,
5236 build-time or run-time dependencies of the package. Here, we define an
5237 input called @code{"gawk"} whose value is that of the @var{gawk}
5238 variable; @var{gawk} is itself bound to a @code{<package>} object.
5240 @cindex backquote (quasiquote)
5243 @cindex comma (unquote)
5247 @findex unquote-splicing
5248 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5249 us to introduce a literal list in the @code{inputs} field, while
5250 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5251 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5254 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5255 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5256 of ensuring that they are present (@pxref{Build Systems}).
5258 However, any other dependencies need to be specified in the
5259 @code{inputs} field. Any dependency not specified here will simply be
5260 unavailable to the build process, possibly leading to a build failure.
5263 @xref{package Reference}, for a full description of possible fields.
5265 Once a package definition is in place, the
5266 package may actually be built using the @code{guix build} command-line
5267 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5268 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5269 package definition using the @command{guix edit} command
5270 (@pxref{Invoking guix edit}).
5271 @xref{Packaging Guidelines}, for
5272 more information on how to test package definitions, and
5273 @ref{Invoking guix lint}, for information on how to check a definition
5274 for style conformance.
5275 @vindex GUIX_PACKAGE_PATH
5276 Lastly, @pxref{Channels}, for information
5277 on how to extend the distribution by adding your own package definitions
5280 Finally, updating the package definition to a new upstream version
5281 can be partly automated by the @command{guix refresh} command
5282 (@pxref{Invoking guix refresh}).
5284 Behind the scenes, a derivation corresponding to the @code{<package>}
5285 object is first computed by the @code{package-derivation} procedure.
5286 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5287 The build actions it prescribes may then be realized by using the
5288 @code{build-derivations} procedure (@pxref{The Store}).
5290 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5291 Return the @code{<derivation>} object of @var{package} for @var{system}
5292 (@pxref{Derivations}).
5294 @var{package} must be a valid @code{<package>} object, and @var{system}
5295 must be a string denoting the target system type---e.g.,
5296 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5297 must be a connection to the daemon, which operates on the store
5298 (@pxref{The Store}).
5302 @cindex cross-compilation
5303 Similarly, it is possible to compute a derivation that cross-builds a
5304 package for some other system:
5306 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5307 @var{package} @var{target} [@var{system}]
5308 Return the @code{<derivation>} object of @var{package} cross-built from
5309 @var{system} to @var{target}.
5311 @var{target} must be a valid GNU triplet denoting the target hardware
5312 and operating system, such as @code{"mips64el-linux-gnu"}
5313 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5316 @cindex package transformations
5317 @cindex input rewriting
5318 @cindex dependency tree rewriting
5319 Packages can be manipulated in arbitrary ways. An example of a useful
5320 transformation is @dfn{input rewriting}, whereby the dependency tree of
5321 a package is rewritten by replacing specific inputs by others:
5323 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5324 [@var{rewrite-name}]
5325 Return a procedure that, when passed a package, replaces its direct and
5326 indirect dependencies (but not its implicit inputs) according to
5327 @var{replacements}. @var{replacements} is a list of package pairs; the
5328 first element of each pair is the package to replace, and the second one
5331 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5332 the name of a package and returns its new name after rewrite.
5336 Consider this example:
5339 (define libressl-instead-of-openssl
5340 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5342 (package-input-rewriting `((,openssl . ,libressl))))
5344 (define git-with-libressl
5345 (libressl-instead-of-openssl git))
5349 Here we first define a rewriting procedure that replaces @var{openssl}
5350 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5351 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5352 This is exactly what the @option{--with-input} command-line option does
5353 (@pxref{Package Transformation Options, @option{--with-input}}).
5355 The following variant of @code{package-input-rewriting} can match packages to
5356 be replaced by name rather than by identity.
5358 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5359 Return a procedure that, given a package, applies the given @var{replacements} to
5360 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5361 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5362 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5363 replacement for that package.
5366 The example above could be rewritten this way:
5369 (define libressl-instead-of-openssl
5370 ;; Replace all the packages called "openssl" with LibreSSL.
5371 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5374 The key difference here is that, this time, packages are matched by spec and
5375 not by identity. In other words, any package in the graph that is called
5376 @code{openssl} will be replaced.
5378 A more generic procedure to rewrite a package dependency graph is
5379 @code{package-mapping}: it supports arbitrary changes to nodes in the
5382 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5383 Return a procedure that, given a package, applies @var{proc} to all the packages
5384 depended on and returns the resulting package. The procedure stops recursion
5385 when @var{cut?} returns true for a given package.
5389 * package Reference:: The package data type.
5390 * origin Reference:: The origin data type.
5394 @node package Reference
5395 @subsection @code{package} Reference
5397 This section summarizes all the options available in @code{package}
5398 declarations (@pxref{Defining Packages}).
5400 @deftp {Data Type} package
5401 This is the data type representing a package recipe.
5405 The name of the package, as a string.
5407 @item @code{version}
5408 The version of the package, as a string.
5411 An object telling how the source code for the package should be
5412 acquired. Most of the time, this is an @code{origin} object, which
5413 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5414 can also be any other ``file-like'' object such as a @code{local-file},
5415 which denotes a file from the local file system (@pxref{G-Expressions,
5416 @code{local-file}}).
5418 @item @code{build-system}
5419 The build system that should be used to build the package (@pxref{Build
5422 @item @code{arguments} (default: @code{'()})
5423 The arguments that should be passed to the build system. This is a
5424 list, typically containing sequential keyword-value pairs.
5426 @item @code{inputs} (default: @code{'()})
5427 @itemx @code{native-inputs} (default: @code{'()})
5428 @itemx @code{propagated-inputs} (default: @code{'()})
5429 @cindex inputs, of packages
5430 These fields list dependencies of the package. Each one is a list of
5431 tuples, where each tuple has a label for the input (a string) as its
5432 first element, a package, origin, or derivation as its second element,
5433 and optionally the name of the output thereof that should be used, which
5434 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5435 more on package outputs). For example, the list below specifies three
5439 `(("libffi" ,libffi)
5440 ("libunistring" ,libunistring)
5441 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5444 @cindex cross compilation, package dependencies
5445 The distinction between @code{native-inputs} and @code{inputs} is
5446 necessary when considering cross-compilation. When cross-compiling,
5447 dependencies listed in @code{inputs} are built for the @emph{target}
5448 architecture; conversely, dependencies listed in @code{native-inputs}
5449 are built for the architecture of the @emph{build} machine.
5451 @code{native-inputs} is typically used to list tools needed at
5452 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5453 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5454 this area (@pxref{Invoking guix lint}).
5456 @anchor{package-propagated-inputs}
5457 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5458 specified packages will be automatically installed alongside the package
5459 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5460 package}}, for information on how @command{guix package} deals with
5463 For example this is necessary when a C/C++ library needs headers of
5464 another library to compile, or when a pkg-config file refers to another
5465 one @i{via} its @code{Requires} field.
5467 Another example where @code{propagated-inputs} is useful is for languages
5468 that lack a facility to record the run-time search path akin to the
5469 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5470 more. To ensure that libraries written in those languages can find
5471 library code they depend on at run time, run-time dependencies must be
5472 listed in @code{propagated-inputs} rather than @code{inputs}.
5474 @item @code{outputs} (default: @code{'("out")})
5475 The list of output names of the package. @xref{Packages with Multiple
5476 Outputs}, for typical uses of additional outputs.
5478 @item @code{native-search-paths} (default: @code{'()})
5479 @itemx @code{search-paths} (default: @code{'()})
5480 A list of @code{search-path-specification} objects describing
5481 search-path environment variables honored by the package.
5483 @item @code{replacement} (default: @code{#f})
5484 This must be either @code{#f} or a package object that will be used as a
5485 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5488 @item @code{synopsis}
5489 A one-line description of the package.
5491 @item @code{description}
5492 A more elaborate description of the package.
5494 @item @code{license}
5495 @cindex license, of packages
5496 The license of the package; a value from @code{(guix licenses)},
5497 or a list of such values.
5499 @item @code{home-page}
5500 The URL to the home-page of the package, as a string.
5502 @item @code{supported-systems} (default: @var{%supported-systems})
5503 The list of systems supported by the package, as strings of the form
5504 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5506 @item @code{maintainers} (default: @code{'()})
5507 The list of maintainers of the package, as @code{maintainer} objects.
5509 @item @code{location} (default: source location of the @code{package} form)
5510 The source location of the package. It is useful to override this when
5511 inheriting from another package, in which case this field is not
5512 automatically corrected.
5516 @deffn {Scheme Syntax} this-package
5517 When used in the @emph{lexical scope} of a package field definition, this
5518 identifier resolves to the package being defined.
5520 The example below shows how to add a package as a native input of itself when
5528 ;; When cross-compiled, Guile, for example, depends on
5529 ;; a native version of itself. Add it here.
5530 (native-inputs (if (%current-target-system)
5531 `(("self" ,this-package))
5535 It is an error to refer to @code{this-package} outside a package definition.
5538 @node origin Reference
5539 @subsection @code{origin} Reference
5541 This section summarizes all the options available in @code{origin}
5542 declarations (@pxref{Defining Packages}).
5544 @deftp {Data Type} origin
5545 This is the data type representing a source code origin.
5549 An object containing the URI of the source. The object type depends on
5550 the @code{method} (see below). For example, when using the
5551 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5552 values are: a URL represented as a string, or a list thereof.
5555 A procedure that handles the URI.
5560 @item @var{url-fetch} from @code{(guix download)}
5561 download a file from the HTTP, HTTPS, or FTP URL specified in the
5565 @item @var{git-fetch} from @code{(guix git-download)}
5566 clone the Git version control repository, and check out the revision
5567 specified in the @code{uri} field as a @code{git-reference} object; a
5568 @code{git-reference} looks like this:
5572 (url "https://git.savannah.gnu.org/git/hello.git")
5578 A bytevector containing the SHA-256 hash of the source. Typically the
5579 @code{base32} form is used here to generate the bytevector from a
5582 You can obtain this information using @code{guix download}
5583 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5586 @item @code{file-name} (default: @code{#f})
5587 The file name under which the source code should be saved. When this is
5588 @code{#f}, a sensible default value will be used in most cases. In case
5589 the source is fetched from a URL, the file name from the URL will be
5590 used. For version control checkouts, it is recommended to provide the
5591 file name explicitly because the default is not very descriptive.
5593 @item @code{patches} (default: @code{'()})
5594 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5595 file-like objects}) pointing to patches to be applied to the source.
5597 This list of patches must be unconditional. In particular, it cannot
5598 depend on the value of @code{%current-system} or
5599 @code{%current-target-system}.
5601 @item @code{snippet} (default: @code{#f})
5602 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5603 in the source directory. This is a convenient way to modify the source,
5604 sometimes more convenient than a patch.
5606 @item @code{patch-flags} (default: @code{'("-p1")})
5607 A list of command-line flags that should be passed to the @code{patch}
5610 @item @code{patch-inputs} (default: @code{#f})
5611 Input packages or derivations to the patching process. When this is
5612 @code{#f}, the usual set of inputs necessary for patching are provided,
5613 such as GNU@tie{}Patch.
5615 @item @code{modules} (default: @code{'()})
5616 A list of Guile modules that should be loaded during the patching
5617 process and while running the code in the @code{snippet} field.
5619 @item @code{patch-guile} (default: @code{#f})
5620 The Guile package that should be used in the patching process. When
5621 this is @code{#f}, a sensible default is used.
5627 @section Build Systems
5629 @cindex build system
5630 Each package definition specifies a @dfn{build system} and arguments for
5631 that build system (@pxref{Defining Packages}). This @code{build-system}
5632 field represents the build procedure of the package, as well as implicit
5633 dependencies of that build procedure.
5635 Build systems are @code{<build-system>} objects. The interface to
5636 create and manipulate them is provided by the @code{(guix build-system)}
5637 module, and actual build systems are exported by specific modules.
5639 @cindex bag (low-level package representation)
5640 Under the hood, build systems first compile package objects to
5641 @dfn{bags}. A @dfn{bag} is like a package, but with less
5642 ornamentation---in other words, a bag is a lower-level representation of
5643 a package, which includes all the inputs of that package, including some
5644 that were implicitly added by the build system. This intermediate
5645 representation is then compiled to a derivation (@pxref{Derivations}).
5647 Build systems accept an optional list of @dfn{arguments}. In package
5648 definitions, these are passed @i{via} the @code{arguments} field
5649 (@pxref{Defining Packages}). They are typically keyword arguments
5650 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5651 Guile Reference Manual}). The value of these arguments is usually
5652 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5653 by the daemon (@pxref{Derivations}).
5655 The main build system is @var{gnu-build-system}, which implements the
5656 standard build procedure for GNU and many other packages. It
5657 is provided by the @code{(guix build-system gnu)} module.
5659 @defvr {Scheme Variable} gnu-build-system
5660 @var{gnu-build-system} represents the GNU Build System, and variants
5661 thereof (@pxref{Configuration, configuration and makefile conventions,,
5662 standards, GNU Coding Standards}).
5664 @cindex build phases
5665 In a nutshell, packages using it are configured, built, and installed with
5666 the usual @code{./configure && make && make check && make install}
5667 command sequence. In practice, a few additional steps are often needed.
5668 All these steps are split up in separate @dfn{phases},
5669 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5670 modules for more details about the build phases.}:
5674 Unpack the source tarball, and change the current directory to the
5675 extracted source tree. If the source is actually a directory, copy it
5676 to the build tree, and enter that directory.
5678 @item patch-source-shebangs
5679 Patch shebangs encountered in source files so they refer to the right
5680 store file names. For instance, this changes @code{#!/bin/sh} to
5681 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
5684 Run the @file{configure} script with a number of default options, such
5685 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
5686 by the @code{#:configure-flags} argument.
5689 Run @code{make} with the list of flags specified with
5690 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
5691 (the default), build with @code{make -j}.
5694 Run @code{make check}, or some other target specified with
5695 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
5696 @code{#:parallel-tests?} argument is true (the default), run @code{make
5700 Run @code{make install} with the flags listed in @code{#:make-flags}.
5702 @item patch-shebangs
5703 Patch shebangs on the installed executable files.
5706 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
5707 is false), copying them to the @code{debug} output when available
5708 (@pxref{Installing Debugging Files}).
5711 @vindex %standard-phases
5712 The build-side module @code{(guix build gnu-build-system)} defines
5713 @var{%standard-phases} as the default list of build phases.
5714 @var{%standard-phases} is a list of symbol/procedure pairs, where the
5715 procedure implements the actual phase.
5717 The list of phases used for a particular package can be changed with the
5718 @code{#:phases} parameter. For instance, passing:
5721 #:phases (modify-phases %standard-phases (delete 'configure))
5724 means that all the phases described above will be used, except the
5725 @code{configure} phase.
5727 In addition, this build system ensures that the ``standard'' environment
5728 for GNU packages is available. This includes tools such as GCC, libc,
5729 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
5730 build-system gnu)} module for a complete list). We call these the
5731 @dfn{implicit inputs} of a package, because package definitions do not
5732 have to mention them.
5735 Other @code{<build-system>} objects are defined to support other
5736 conventions and tools used by free software packages. They inherit most
5737 of @var{gnu-build-system}, and differ mainly in the set of inputs
5738 implicitly added to the build process, and in the list of phases
5739 executed. Some of these build systems are listed below.
5741 @defvr {Scheme Variable} ant-build-system
5742 This variable is exported by @code{(guix build-system ant)}. It
5743 implements the build procedure for Java packages that can be built with
5744 @url{https://ant.apache.org/, Ant build tool}.
5746 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
5747 provided by the @code{icedtea} package to the set of inputs. Different
5748 packages can be specified with the @code{#:ant} and @code{#:jdk}
5749 parameters, respectively.
5751 When the original package does not provide a suitable Ant build file,
5752 the parameter @code{#:jar-name} can be used to generate a minimal Ant
5753 build file @file{build.xml} with tasks to build the specified jar
5754 archive. In this case the parameter @code{#:source-dir} can be used to
5755 specify the source sub-directory, defaulting to ``src''.
5757 The @code{#:main-class} parameter can be used with the minimal ant
5758 buildfile to specify the main class of the resulting jar. This makes the
5759 jar file executable. The @code{#:test-include} parameter can be used to
5760 specify the list of junit tests to run. It defaults to
5761 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
5762 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
5763 because abstract classes cannot be run as tests.
5765 The parameter @code{#:build-target} can be used to specify the Ant task
5766 that should be run during the @code{build} phase. By default the
5767 ``jar'' task will be run.
5771 @defvr {Scheme Variable} android-ndk-build-system
5772 @cindex Android distribution
5773 @cindex Android NDK build system
5774 This variable is exported by @code{(guix build-system android-ndk)}. It
5775 implements a build procedure for Android NDK (native development kit)
5776 packages using a Guix-specific build process.
5778 The build system assumes that packages install their public interface
5779 (header) files to the subdirectory "include" of the "out" output and
5780 their libraries to the subdirectory "lib" of the "out" output.
5782 It's also assumed that the union of all the dependencies of a package
5783 has no conflicting files.
5785 For the time being, cross-compilation is not supported - so right now
5786 the libraries and header files are assumed to be host tools.
5790 @defvr {Scheme Variable} asdf-build-system/source
5791 @defvrx {Scheme Variable} asdf-build-system/sbcl
5792 @defvrx {Scheme Variable} asdf-build-system/ecl
5794 These variables, exported by @code{(guix build-system asdf)}, implement
5795 build procedures for Common Lisp packages using
5796 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
5797 definition facility for Common Lisp programs and libraries.
5799 The @code{asdf-build-system/source} system installs the packages in
5800 source form, and can be loaded using any common lisp implementation, via
5801 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
5802 systems in the format which a particular implementation understands.
5803 These build systems can also be used to produce executable programs, or
5804 lisp images which contain a set of packages pre-loaded.
5806 The build system uses naming conventions. For binary packages, the
5807 package name should be prefixed with the lisp implementation, such as
5808 @code{sbcl-} for @code{asdf-build-system/sbcl}.
5810 Additionally, the corresponding source package should be labeled using
5811 the same convention as python packages (see @ref{Python Modules}), using
5812 the @code{cl-} prefix.
5814 For binary packages, each system should be defined as a Guix package.
5815 If one package @code{origin} contains several systems, package variants
5816 can be created in order to build all the systems. Source packages,
5817 which use @code{asdf-build-system/source}, may contain several systems.
5819 In order to create executable programs and images, the build-side
5820 procedures @code{build-program} and @code{build-image} can be used.
5821 They should be called in a build phase after the @code{create-symlinks}
5822 phase, so that the system which was just built can be used within the
5823 resulting image. @code{build-program} requires a list of Common Lisp
5824 expressions to be passed as the @code{#:entry-program} argument.
5826 If the system is not defined within its own @code{.asd} file of the same
5827 name, then the @code{#:asd-file} parameter should be used to specify
5828 which file the system is defined in. Furthermore, if the package
5829 defines a system for its tests in a separate file, it will be loaded
5830 before the tests are run if it is specified by the
5831 @code{#:test-asd-file} parameter. If it is not set, the files
5832 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
5833 and @code{test.asd} will be tried if they exist.
5835 If for some reason the package must be named in a different way than the
5836 naming conventions suggest, the @code{#:asd-system-name} parameter can
5837 be used to specify the name of the system.
5841 @defvr {Scheme Variable} cargo-build-system
5842 @cindex Rust programming language
5843 @cindex Cargo (Rust build system)
5844 This variable is exported by @code{(guix build-system cargo)}. It
5845 supports builds of packages using Cargo, the build tool of the
5846 @uref{https://www.rust-lang.org, Rust programming language}.
5848 It adds @code{rustc} and @code{cargo} to the set of inputs.
5849 A different Rust package can be specified with the @code{#:rust} parameter.
5851 Regular cargo dependencies should be added to the package definition via the
5852 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
5853 spec can be a package or a source definition. Note that the spec must
5854 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
5855 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
5856 should be added to the package definition via the
5857 @code{#:cargo-development-inputs} parameter.
5859 In its @code{configure} phase, this build system will make any source inputs
5860 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
5861 parameters available to cargo. It will also remove an included
5862 @code{Cargo.lock} file to be recreated by @code{cargo} during the
5863 @code{build} phase. The @code{install} phase installs any crate the binaries
5864 if they are defined by the crate.
5867 @cindex Clojure (programming language)
5868 @cindex simple Clojure build system
5869 @defvr {Scheme Variable} clojure-build-system
5870 This variable is exported by @code{(guix build-system clojure)}. It implements
5871 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
5872 using plain old @code{compile} in Clojure. Cross-compilation is not supported
5875 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
5876 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
5877 @code{#:zip} parameters, respectively.
5879 A list of source directories, test directories and jar names can be specified
5880 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
5881 parameters, respectively. Compile directory and main class can be specified
5882 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
5883 Other parameters are documented below.
5885 This build system is an extension of @var{ant-build-system}, but with the
5886 following phases changed:
5891 This phase calls @code{compile} in Clojure to compile source files and runs
5892 @command{jar} to create jars from both source files and compiled files
5893 according to the include list and exclude list specified in
5894 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
5895 has priority over the include list. These lists consist of symbols
5896 representing Clojure libraries or the special keyword @code{#:all} representing
5897 all Clojure libraries found under the source directories. The parameter
5898 @code{#:omit-source?} decides if source should be included into the jars.
5901 This phase runs tests according to the include list and exclude list specified
5902 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
5903 meanings are analogous to that of @code{#:aot-include} and
5904 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
5905 stands for all Clojure libraries found under the test directories. The
5906 parameter @code{#:tests?} decides if tests should be run.
5909 This phase installs all jars built previously.
5912 Apart from the above, this build system also contains an additional phase:
5917 This phase installs all top-level files with base name matching
5918 @var{%doc-regex}. A different regex can be specified with the
5919 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
5920 directories specified in @code{#:doc-dirs} are installed as well.
5924 @defvr {Scheme Variable} cmake-build-system
5925 This variable is exported by @code{(guix build-system cmake)}. It
5926 implements the build procedure for packages using the
5927 @url{https://www.cmake.org, CMake build tool}.
5929 It automatically adds the @code{cmake} package to the set of inputs.
5930 Which package is used can be specified with the @code{#:cmake}
5933 The @code{#:configure-flags} parameter is taken as a list of flags
5934 passed to the @command{cmake} command. The @code{#:build-type}
5935 parameter specifies in abstract terms the flags passed to the compiler;
5936 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
5937 debugging information''), which roughly means that code is compiled with
5938 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
5941 @defvr {Scheme Variable} dune-build-system
5942 This variable is exported by @code{(guix build-system dune)}. It
5943 supports builds of packages using @uref{https://dune.build/, Dune}, a build
5944 tool for the OCaml programming language. It is implemented as an extension
5945 of the @code{ocaml-build-system} which is described below. As such, the
5946 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
5949 It automatically adds the @code{dune} package to the set of inputs.
5950 Which package is used can be specified with the @code{#:dune}
5953 There is no @code{configure} phase because dune packages typically don't
5954 need to be configured. The @code{#:build-flags} parameter is taken as a
5955 list of flags passed to the @code{dune} command during the build.
5957 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
5958 command instead of the more recent @code{dune} command while building
5959 a package. Its default value is @code{#f}.
5961 The @code{#:package} parameter can be passed to specify a package name, which
5962 is useful when a package contains multiple packages and you want to build
5963 only one of them. This is equivalent to passing the @code{-p} argument to
5967 @defvr {Scheme Variable} go-build-system
5968 This variable is exported by @code{(guix build-system go)}. It
5969 implements a build procedure for Go packages using the standard
5970 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
5971 Go build mechanisms}.
5973 The user is expected to provide a value for the key @code{#:import-path}
5974 and, in some cases, @code{#:unpack-path}. The
5975 @url{https://golang.org/doc/code.html#ImportPaths, import path}
5976 corresponds to the file system path expected by the package's build
5977 scripts and any referring packages, and provides a unique way to
5978 refer to a Go package. It is typically based on a combination of the
5979 package source code's remote URI and file system hierarchy structure. In
5980 some cases, you will need to unpack the package's source code to a
5981 different directory structure than the one indicated by the import path,
5982 and @code{#:unpack-path} should be used in such cases.
5984 Packages that provide Go libraries should install their source code into
5985 the built output. The key @code{#:install-source?}, which defaults to
5986 @code{#t}, controls whether or not the source code is installed. It can
5987 be set to @code{#f} for packages that only provide executable files.
5990 @defvr {Scheme Variable} glib-or-gtk-build-system
5991 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
5992 is intended for use with packages making use of GLib or GTK+.
5994 This build system adds the following two phases to the ones defined by
5995 @var{gnu-build-system}:
5998 @item glib-or-gtk-wrap
5999 The phase @code{glib-or-gtk-wrap} ensures that programs in
6000 @file{bin/} are able to find GLib ``schemas'' and
6001 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6002 modules}. This is achieved by wrapping the programs in launch scripts
6003 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
6004 environment variables.
6006 It is possible to exclude specific package outputs from that wrapping
6007 process by listing their names in the
6008 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6009 when an output is known not to contain any GLib or GTK+ binaries, and
6010 where wrapping would gratuitously add a dependency of that output on
6013 @item glib-or-gtk-compile-schemas
6014 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6015 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6016 GSettings schemas} of GLib are compiled. Compilation is performed by the
6017 @command{glib-compile-schemas} program. It is provided by the package
6018 @code{glib:bin} which is automatically imported by the build system.
6019 The @code{glib} package providing @command{glib-compile-schemas} can be
6020 specified with the @code{#:glib} parameter.
6023 Both phases are executed after the @code{install} phase.
6026 @defvr {Scheme Variable} guile-build-system
6027 This build system is for Guile packages that consist exclusively of Scheme
6028 code and that are so lean that they don't even have a makefile, let alone a
6029 @file{configure} script. It compiles Scheme code using @command{guild
6030 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6031 installs the @file{.scm} and @file{.go} files in the right place. It also
6032 installs documentation.
6034 This build system supports cross-compilation by using the @code{--target}
6035 option of @command{guild compile}.
6037 Packages built with @code{guile-build-system} must provide a Guile package in
6038 their @code{native-inputs} field.
6041 @defvr {Scheme Variable} julia-build-system
6042 This variable is exported by @code{(guix build-system julia)}. It implements
6043 the build procedure used by @uref{https://julialang.org/, julia} packages,
6044 which essentially is similar to running @command{julia -e 'using Pkg;
6045 Pkg.add(package)'} in an environment where @code{JULIA_LOAD_PATH} contains the
6046 paths to all Julia package inputs. Tests are run not run.
6048 Julia packages require the source @code{file-name} to be the real name of the
6049 package, correctly capitalized.
6051 For packages requiring shared library dependencies, you may need to write the
6052 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6053 variable = /gnu/store/libary.so} for each dependency, plus a void function
6054 @code{check_deps() = nothing}.
6056 Some older packages that aren't using @file{Package.toml} yet, will require
6057 this file to be created, too. The function @code{julia-create-package-toml}
6058 helps creating the file. You need to pass the outputs and the source of the
6059 package, it's name (the same as the @code{file-name} parameter), the package
6060 uuid, the package version, and a list of dependencies specified by their name
6064 @defvr {Scheme Variable} minify-build-system
6065 This variable is exported by @code{(guix build-system minify)}. It
6066 implements a minification procedure for simple JavaScript packages.
6068 It adds @code{uglify-js} to the set of inputs and uses it to compress
6069 all JavaScript files in the @file{src} directory. A different minifier
6070 package can be specified with the @code{#:uglify-js} parameter, but it
6071 is expected that the package writes the minified code to the standard
6074 When the input JavaScript files are not all located in the @file{src}
6075 directory, the parameter @code{#:javascript-files} can be used to
6076 specify a list of file names to feed to the minifier.
6079 @defvr {Scheme Variable} ocaml-build-system
6080 This variable is exported by @code{(guix build-system ocaml)}. It implements
6081 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6082 of choosing the correct set of commands to run for each package. OCaml
6083 packages can expect many different commands to be run. This build system will
6086 When the package has a @file{setup.ml} file present at the top-level, it will
6087 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6088 @code{ocaml setup.ml -install}. The build system will assume that this file
6089 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6090 care of setting the prefix and enabling tests if they are not disabled. You
6091 can pass configure and build flags with the @code{#:configure-flags} and
6092 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6093 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6094 bypass this system in the build and install phases.
6096 When the package has a @file{configure} file, it is assumed that it is a
6097 hand-made configure script that requires a different argument format than
6098 in the @code{gnu-build-system}. You can add more flags with the
6099 @code{#:configure-flags} key.
6101 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6102 @code{#t}), it will be used and more flags can be passed to the build and
6103 install phases with the @code{#:make-flags} key.
6105 Finally, some packages do not have these files and use a somewhat standard
6106 location for its build system. In that case, the build system will run
6107 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6108 providing the path to the required findlib module. Additional flags can
6109 be passed via the @code{#:build-flags} key. Install is taken care of by
6110 @command{opam-installer}. In this case, the @code{opam} package must
6111 be added to the @code{native-inputs} field of the package definition.
6113 Note that most OCaml packages assume they will be installed in the same
6114 directory as OCaml, which is not what we want in guix. In particular, they
6115 will install @file{.so} files in their module's directory, which is usually
6116 fine because it is in the OCaml compiler directory. In guix though, these
6117 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6118 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6119 @file{.so} libraries should be installed.
6122 @defvr {Scheme Variable} python-build-system
6123 This variable is exported by @code{(guix build-system python)}. It
6124 implements the more or less standard build procedure used by Python
6125 packages, which consists in running @code{python setup.py build} and
6126 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6128 For packages that install stand-alone Python programs under @code{bin/},
6129 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6130 environment variable points to all the Python libraries they depend on.
6132 Which Python package is used to perform the build can be specified with
6133 the @code{#:python} parameter. This is a useful way to force a package
6134 to be built for a specific version of the Python interpreter, which
6135 might be necessary if the package is only compatible with a single
6136 interpreter version.
6138 By default guix calls @code{setup.py} under control of
6139 @code{setuptools}, much like @command{pip} does. Some packages are not
6140 compatible with setuptools (and pip), thus you can disable this by
6141 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6144 @defvr {Scheme Variable} perl-build-system
6145 This variable is exported by @code{(guix build-system perl)}. It
6146 implements the standard build procedure for Perl packages, which either
6147 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6148 followed by @code{Build} and @code{Build install}; or in running
6149 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6150 @code{make} and @code{make install}, depending on which of
6151 @code{Build.PL} or @code{Makefile.PL} is present in the package
6152 distribution. Preference is given to the former if both @code{Build.PL}
6153 and @code{Makefile.PL} exist in the package distribution. This
6154 preference can be reversed by specifying @code{#t} for the
6155 @code{#:make-maker?} parameter.
6157 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6158 passes flags specified by the @code{#:make-maker-flags} or
6159 @code{#:module-build-flags} parameter, respectively.
6161 Which Perl package is used can be specified with @code{#:perl}.
6164 @defvr {Scheme Variable} r-build-system
6165 This variable is exported by @code{(guix build-system r)}. It
6166 implements the build procedure used by @uref{https://r-project.org, R}
6167 packages, which essentially is little more than running @code{R CMD
6168 INSTALL --library=/gnu/store/@dots{}} in an environment where
6169 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6170 are run after installation using the R function
6171 @code{tools::testInstalledPackage}.
6174 @defvr {Scheme Variable} rakudo-build-system
6175 This variable is exported by @code{(guix build-system rakudo)}. It
6176 implements the build procedure used by @uref{https://rakudo.org/,
6177 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6178 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6179 installs the binaries, library files and the resources, as well as wrap
6180 the files under the @code{bin/} directory. Tests can be skipped by
6181 passing @code{#f} to the @code{tests?} parameter.
6183 Which rakudo package is used can be specified with @code{rakudo}.
6184 Which perl6-tap-harness package used for the tests can be specified with
6185 @code{#:prove6} or removed by passing @code{#f} to the
6186 @code{with-prove6?} parameter.
6187 Which perl6-zef package used for tests and installing can be specified
6188 with @code{#:zef} or removed by passing @code{#f} to the
6189 @code{with-zef?} parameter.
6192 @defvr {Scheme Variable} texlive-build-system
6193 This variable is exported by @code{(guix build-system texlive)}. It is
6194 used to build TeX packages in batch mode with a specified engine. The
6195 build system sets the @code{TEXINPUTS} variable to find all TeX source
6196 files in the inputs.
6198 By default it runs @code{luatex} on all files ending on @code{ins}. A
6199 different engine and format can be specified with the
6200 @code{#:tex-format} argument. Different build targets can be specified
6201 with the @code{#:build-targets} argument, which expects a list of file
6202 names. The build system adds only @code{texlive-bin} and
6203 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6204 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6205 and @code{#:texlive-latex-base}, respectively.
6207 The @code{#:tex-directory} parameter tells the build system where to
6208 install the built files under the texmf tree.
6211 @defvr {Scheme Variable} ruby-build-system
6212 This variable is exported by @code{(guix build-system ruby)}. It
6213 implements the RubyGems build procedure used by Ruby packages, which
6214 involves running @code{gem build} followed by @code{gem install}.
6216 The @code{source} field of a package that uses this build system
6217 typically references a gem archive, since this is the format that Ruby
6218 developers use when releasing their software. The build system unpacks
6219 the gem archive, potentially patches the source, runs the test suite,
6220 repackages the gem, and installs it. Additionally, directories and
6221 tarballs may be referenced to allow building unreleased gems from Git or
6222 a traditional source release tarball.
6224 Which Ruby package is used can be specified with the @code{#:ruby}
6225 parameter. A list of additional flags to be passed to the @command{gem}
6226 command can be specified with the @code{#:gem-flags} parameter.
6229 @defvr {Scheme Variable} waf-build-system
6230 This variable is exported by @code{(guix build-system waf)}. It
6231 implements a build procedure around the @code{waf} script. The common
6232 phases---@code{configure}, @code{build}, and @code{install}---are
6233 implemented by passing their names as arguments to the @code{waf}
6236 The @code{waf} script is executed by the Python interpreter. Which
6237 Python package is used to run the script can be specified with the
6238 @code{#:python} parameter.
6241 @defvr {Scheme Variable} scons-build-system
6242 This variable is exported by @code{(guix build-system scons)}. It
6243 implements the build procedure used by the SCons software construction
6244 tool. This build system runs @code{scons} to build the package,
6245 @code{scons test} to run tests, and then @code{scons install} to install
6248 Additional flags to be passed to @code{scons} can be specified with the
6249 @code{#:scons-flags} parameter. The version of Python used to run SCons
6250 can be specified by selecting the appropriate SCons package with the
6251 @code{#:scons} parameter.
6254 @defvr {Scheme Variable} haskell-build-system
6255 This variable is exported by @code{(guix build-system haskell)}. It
6256 implements the Cabal build procedure used by Haskell packages, which
6257 involves running @code{runhaskell Setup.hs configure
6258 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6259 Instead of installing the package by running @code{runhaskell Setup.hs
6260 install}, to avoid trying to register libraries in the read-only
6261 compiler store directory, the build system uses @code{runhaskell
6262 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6263 addition, the build system generates the package documentation by
6264 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6265 is passed. Optional Haddock parameters can be passed with the help of
6266 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6267 not found, the build system looks for @code{Setup.lhs} instead.
6269 Which Haskell compiler is used can be specified with the @code{#:haskell}
6270 parameter which defaults to @code{ghc}.
6273 @defvr {Scheme Variable} dub-build-system
6274 This variable is exported by @code{(guix build-system dub)}. It
6275 implements the Dub build procedure used by D packages, which
6276 involves running @code{dub build} and @code{dub run}.
6277 Installation is done by copying the files manually.
6279 Which D compiler is used can be specified with the @code{#:ldc}
6280 parameter which defaults to @code{ldc}.
6283 @defvr {Scheme Variable} emacs-build-system
6284 This variable is exported by @code{(guix build-system emacs)}. It
6285 implements an installation procedure similar to the packaging system
6286 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6288 It first creates the @code{@var{package}-autoloads.el} file, then it
6289 byte compiles all Emacs Lisp files. Differently from the Emacs
6290 packaging system, the Info documentation files are moved to the standard
6291 documentation directory and the @file{dir} file is deleted. Each
6292 package is installed in its own directory under
6293 @file{share/emacs/site-lisp/guix.d}.
6296 @defvr {Scheme Variable} font-build-system
6297 This variable is exported by @code{(guix build-system font)}. It
6298 implements an installation procedure for font packages where upstream
6299 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6300 need to be copied into place. It copies font files to standard
6301 locations in the output directory.
6304 @defvr {Scheme Variable} meson-build-system
6305 This variable is exported by @code{(guix build-system meson)}. It
6306 implements the build procedure for packages that use
6307 @url{https://mesonbuild.com, Meson} as their build system.
6309 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6310 of inputs, and they can be changed with the parameters @code{#:meson}
6311 and @code{#:ninja} if needed. The default Meson is
6312 @code{meson-for-build}, which is special because it doesn't clear the
6313 @code{RUNPATH} of binaries and libraries when they are installed.
6315 This build system is an extension of @var{gnu-build-system}, but with the
6316 following phases changed to some specific for Meson:
6321 The phase runs @code{meson} with the flags specified in
6322 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6323 @code{plain} unless something else is specified in @code{#:build-type}.
6326 The phase runs @code{ninja} to build the package in parallel by default, but
6327 this can be changed with @code{#:parallel-build?}.
6330 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6331 which is @code{"test"} by default.
6334 The phase runs @code{ninja install} and can not be changed.
6337 Apart from that, the build system also adds the following phases:
6342 This phase ensures that all binaries can find the libraries they need.
6343 It searches for required libraries in subdirectories of the package being
6344 built, and adds those to @code{RUNPATH} where needed. It also removes
6345 references to libraries left over from the build phase by
6346 @code{meson-for-build}, such as test dependencies, that aren't actually
6347 required for the program to run.
6349 @item glib-or-gtk-wrap
6350 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6351 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6353 @item glib-or-gtk-compile-schemas
6354 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6355 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6359 @defvr {Scheme Variable} linux-module-build-system
6360 @var{linux-module-build-system} allows building Linux kernel modules.
6362 @cindex build phases
6363 This build system is an extension of @var{gnu-build-system}, but with the
6364 following phases changed:
6369 This phase configures the environment so that the Linux kernel's Makefile
6370 can be used to build the external kernel module.
6373 This phase uses the Linux kernel's Makefile in order to build the external
6377 This phase uses the Linux kernel's Makefile in order to install the external
6381 It is possible and useful to specify the Linux kernel to use for building
6382 the module (in the "arguments" form of a package using the
6383 linux-module-build-system, use the key #:linux to specify it).
6386 @defvr {Scheme Variable} node-build-system
6387 This variable is exported by @code{(guix build-system node)}. It
6388 implements the build procedure used by @uref{http://nodejs.org,
6389 Node.js}, which implements an approximation of the @code{npm install}
6390 command, followed by an @code{npm test} command.
6392 Which Node.js package is used to interpret the @code{npm} commands can
6393 be specified with the @code{#:node} parameter which defaults to
6397 Lastly, for packages that do not need anything as sophisticated, a
6398 ``trivial'' build system is provided. It is trivial in the sense that
6399 it provides basically no support: it does not pull any implicit inputs,
6400 and does not have a notion of build phases.
6402 @defvr {Scheme Variable} trivial-build-system
6403 This variable is exported by @code{(guix build-system trivial)}.
6405 This build system requires a @code{#:builder} argument. This argument
6406 must be a Scheme expression that builds the package output(s)---as
6407 with @code{build-expression->derivation} (@pxref{Derivations,
6408 @code{build-expression->derivation}}).
6418 Conceptually, the @dfn{store} is the place where derivations that have
6419 been built successfully are stored---by default, @file{/gnu/store}.
6420 Sub-directories in the store are referred to as @dfn{store items} or
6421 sometimes @dfn{store paths}. The store has an associated database that
6422 contains information such as the store paths referred to by each store
6423 path, and the list of @emph{valid} store items---results of successful
6424 builds. This database resides in @file{@var{localstatedir}/guix/db},
6425 where @var{localstatedir} is the state directory specified @i{via}
6426 @option{--localstatedir} at configure time, usually @file{/var}.
6428 The store is @emph{always} accessed by the daemon on behalf of its clients
6429 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6430 connect to the daemon over a Unix-domain socket, send requests to it,
6431 and read the result---these are remote procedure calls, or RPCs.
6434 Users must @emph{never} modify files under @file{/gnu/store} directly.
6435 This would lead to inconsistencies and break the immutability
6436 assumptions of Guix's functional model (@pxref{Introduction}).
6438 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6439 how to check the integrity of the store and attempt recovery from
6440 accidental modifications.
6443 The @code{(guix store)} module provides procedures to connect to the
6444 daemon, and to perform RPCs. These are described below. By default,
6445 @code{open-connection}, and thus all the @command{guix} commands,
6446 connect to the local daemon or to the URI specified by the
6447 @code{GUIX_DAEMON_SOCKET} environment variable.
6449 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6450 When set, the value of this variable should be a file name or a URI
6451 designating the daemon endpoint. When it is a file name, it denotes a
6452 Unix-domain socket to connect to. In addition to file names, the
6453 supported URI schemes are:
6458 These are for Unix-domain sockets.
6459 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6460 @file{/var/guix/daemon-socket/socket}.
6463 @cindex daemon, remote access
6464 @cindex remote access to the daemon
6465 @cindex daemon, cluster setup
6466 @cindex clusters, daemon setup
6467 These URIs denote connections over TCP/IP, without encryption nor
6468 authentication of the remote host. The URI must specify the host name
6469 and optionally a port number (by default port 44146 is used):
6472 guix://master.guix.example.org:1234
6475 This setup is suitable on local networks, such as clusters, where only
6476 trusted nodes may connect to the build daemon at
6477 @code{master.guix.example.org}.
6479 The @code{--listen} option of @command{guix-daemon} can be used to
6480 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6484 @cindex SSH access to build daemons
6485 These URIs allow you to connect to a remote daemon over
6486 SSH@footnote{This feature requires Guile-SSH (@pxref{Requirements}).}.
6487 A typical URL might look like this:
6490 ssh://charlie@@guix.example.org:22
6493 As for @command{guix copy}, the usual OpenSSH client configuration files
6494 are honored (@pxref{Invoking guix copy}).
6497 Additional URI schemes may be supported in the future.
6499 @c XXX: Remove this note when the protocol incurs fewer round trips
6500 @c and when (guix derivations) no longer relies on file system access.
6502 The ability to connect to remote build daemons is considered
6503 experimental as of @value{VERSION}. Please get in touch with us to
6504 share any problems or suggestions you may have (@pxref{Contributing}).
6508 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6509 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6510 @var{reserve-space?} is true, instruct it to reserve a little bit of
6511 extra space on the file system so that the garbage collector can still
6512 operate should the disk become full. Return a server object.
6514 @var{file} defaults to @code{%default-socket-path}, which is the normal
6515 location given the options that were passed to @command{configure}.
6518 @deffn {Scheme Procedure} close-connection @var{server}
6519 Close the connection to @var{server}.
6522 @defvr {Scheme Variable} current-build-output-port
6523 This variable is bound to a SRFI-39 parameter, which refers to the port
6524 where build and error logs sent by the daemon should be written.
6527 Procedures that make RPCs all take a server object as their first
6530 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6531 @cindex invalid store items
6532 Return @code{#t} when @var{path} designates a valid store item and
6533 @code{#f} otherwise (an invalid item may exist on disk but still be
6534 invalid, for instance because it is the result of an aborted or failed
6537 A @code{&store-protocol-error} condition is raised if @var{path} is not
6538 prefixed by the store directory (@file{/gnu/store}).
6541 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6542 Add @var{text} under file @var{name} in the store, and return its store
6543 path. @var{references} is the list of store paths referred to by the
6544 resulting store path.
6547 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6549 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6550 file names, or derivation/output pairs, using the specified
6551 @var{mode}---@code{(build-mode normal)} by default.
6554 Note that the @code{(guix monads)} module provides a monad as well as
6555 monadic versions of the above procedures, with the goal of making it
6556 more convenient to work with code that accesses the store (@pxref{The
6560 @i{This section is currently incomplete.}
6563 @section Derivations
6566 Low-level build actions and the environment in which they are performed
6567 are represented by @dfn{derivations}. A derivation contains the
6568 following pieces of information:
6572 The outputs of the derivation---derivations produce at least one file or
6573 directory in the store, but may produce more.
6576 @cindex build-time dependencies
6577 @cindex dependencies, build-time
6578 The inputs of the derivations---i.e., its build-time dependencies---which may
6579 be other derivations or plain files in the store (patches, build scripts,
6583 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
6586 The file name of a build script in the store, along with the arguments
6590 A list of environment variables to be defined.
6594 @cindex derivation path
6595 Derivations allow clients of the daemon to communicate build actions to
6596 the store. They exist in two forms: as an in-memory representation,
6597 both on the client- and daemon-side, and as files in the store whose
6598 name end in @code{.drv}---these files are referred to as @dfn{derivation
6599 paths}. Derivations paths can be passed to the @code{build-derivations}
6600 procedure to perform the build actions they prescribe (@pxref{The
6603 @cindex fixed-output derivations
6604 Operations such as file downloads and version-control checkouts for
6605 which the expected content hash is known in advance are modeled as
6606 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
6607 of a fixed-output derivation are independent of its inputs---e.g., a
6608 source code download produces the same result regardless of the download
6609 method and tools being used.
6612 @cindex run-time dependencies
6613 @cindex dependencies, run-time
6614 The outputs of derivations---i.e., the build results---have a set of
6615 @dfn{references}, as reported by the @code{references} RPC or the
6616 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
6617 are the set of run-time dependencies of the build results. References are a
6618 subset of the inputs of the derivation; this subset is automatically computed
6619 by the build daemon by scanning all the files in the outputs.
6621 The @code{(guix derivations)} module provides a representation of
6622 derivations as Scheme objects, along with procedures to create and
6623 otherwise manipulate derivations. The lowest-level primitive to create
6624 a derivation is the @code{derivation} procedure:
6626 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
6627 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6628 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
6629 [#:system (%current-system)] [#:references-graphs #f] @
6630 [#:allowed-references #f] [#:disallowed-references #f] @
6631 [#:leaked-env-vars #f] [#:local-build? #f] @
6632 [#:substitutable? #t] [#:properties '()]
6633 Build a derivation with the given arguments, and return the resulting
6634 @code{<derivation>} object.
6636 When @var{hash} and @var{hash-algo} are given, a
6637 @dfn{fixed-output derivation} is created---i.e., one whose result is
6638 known in advance, such as a file download. If, in addition,
6639 @var{recursive?} is true, then that fixed output may be an executable
6640 file or a directory and @var{hash} must be the hash of an archive
6641 containing this output.
6643 When @var{references-graphs} is true, it must be a list of file
6644 name/store path pairs. In that case, the reference graph of each store
6645 path is exported in the build environment in the corresponding file, in
6646 a simple text format.
6648 When @var{allowed-references} is true, it must be a list of store items
6649 or outputs that the derivation's output may refer to. Likewise,
6650 @var{disallowed-references}, if true, must be a list of things the
6651 outputs may @emph{not} refer to.
6653 When @var{leaked-env-vars} is true, it must be a list of strings
6654 denoting environment variables that are allowed to ``leak'' from the
6655 daemon's environment to the build environment. This is only applicable
6656 to fixed-output derivations---i.e., when @var{hash} is true. The main
6657 use is to allow variables such as @code{http_proxy} to be passed to
6658 derivations that download files.
6660 When @var{local-build?} is true, declare that the derivation is not a
6661 good candidate for offloading and should rather be built locally
6662 (@pxref{Daemon Offload Setup}). This is the case for small derivations
6663 where the costs of data transfers would outweigh the benefits.
6665 When @var{substitutable?} is false, declare that substitutes of the
6666 derivation's output should not be used (@pxref{Substitutes}). This is
6667 useful, for instance, when building packages that capture details of the
6668 host CPU instruction set.
6670 @var{properties} must be an association list describing ``properties'' of the
6671 derivation. It is kept as-is, uninterpreted, in the derivation.
6675 Here's an example with a shell script as its builder, assuming
6676 @var{store} is an open connection to the daemon, and @var{bash} points
6677 to a Bash executable in the store:
6680 (use-modules (guix utils)
6684 (let ((builder ; add the Bash script to the store
6685 (add-text-to-store store "my-builder.sh"
6686 "echo hello world > $out\n" '())))
6687 (derivation store "foo"
6688 bash `("-e" ,builder)
6689 #:inputs `((,bash) (,builder))
6690 #:env-vars '(("HOME" . "/homeless"))))
6691 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
6694 As can be guessed, this primitive is cumbersome to use directly. A
6695 better approach is to write build scripts in Scheme, of course! The
6696 best course of action for that is to write the build code as a
6697 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
6698 information, @pxref{G-Expressions}.
6700 Once upon a time, @code{gexp->derivation} did not exist and constructing
6701 derivations with build code written in Scheme was achieved with
6702 @code{build-expression->derivation}, documented below. This procedure
6703 is now deprecated in favor of the much nicer @code{gexp->derivation}.
6705 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
6706 @var{name} @var{exp} @
6707 [#:system (%current-system)] [#:inputs '()] @
6708 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6709 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
6710 [#:references-graphs #f] [#:allowed-references #f] @
6711 [#:disallowed-references #f] @
6712 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
6713 Return a derivation that executes Scheme expression @var{exp} as a
6714 builder for derivation @var{name}. @var{inputs} must be a list of
6715 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
6716 @code{"out"} is assumed. @var{modules} is a list of names of Guile
6717 modules from the current search path to be copied in the store,
6718 compiled, and made available in the load path during the execution of
6719 @var{exp}---e.g., @code{((guix build utils) (guix build
6720 gnu-build-system))}.
6722 @var{exp} is evaluated in an environment where @code{%outputs} is bound
6723 to a list of output/path pairs, and where @code{%build-inputs} is bound
6724 to a list of string/output-path pairs made from @var{inputs}.
6725 Optionally, @var{env-vars} is a list of string pairs specifying the name
6726 and value of environment variables visible to the builder. The builder
6727 terminates by passing the result of @var{exp} to @code{exit}; thus, when
6728 @var{exp} returns @code{#f}, the build is considered to have failed.
6730 @var{exp} is built using @var{guile-for-build} (a derivation). When
6731 @var{guile-for-build} is omitted or is @code{#f}, the value of the
6732 @code{%guile-for-build} fluid is used instead.
6734 See the @code{derivation} procedure for the meaning of
6735 @var{references-graphs}, @var{allowed-references},
6736 @var{disallowed-references}, @var{local-build?}, and
6737 @var{substitutable?}.
6741 Here's an example of a single-output derivation that creates a directory
6742 containing one file:
6745 (let ((builder '(let ((out (assoc-ref %outputs "out")))
6746 (mkdir out) ; create /gnu/store/@dots{}-goo
6747 (call-with-output-file (string-append out "/test")
6749 (display '(hello guix) p))))))
6750 (build-expression->derivation store "goo" builder))
6752 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
6756 @node The Store Monad
6757 @section The Store Monad
6761 The procedures that operate on the store described in the previous
6762 sections all take an open connection to the build daemon as their first
6763 argument. Although the underlying model is functional, they either have
6764 side effects or depend on the current state of the store.
6766 The former is inconvenient: the connection to the build daemon has to be
6767 carried around in all those functions, making it impossible to compose
6768 functions that do not take that parameter with functions that do. The
6769 latter can be problematic: since store operations have side effects
6770 and/or depend on external state, they have to be properly sequenced.
6772 @cindex monadic values
6773 @cindex monadic functions
6774 This is where the @code{(guix monads)} module comes in. This module
6775 provides a framework for working with @dfn{monads}, and a particularly
6776 useful monad for our uses, the @dfn{store monad}. Monads are a
6777 construct that allows two things: associating ``context'' with values
6778 (in our case, the context is the store), and building sequences of
6779 computations (here computations include accesses to the store). Values
6780 in a monad---values that carry this additional context---are called
6781 @dfn{monadic values}; procedures that return such values are called
6782 @dfn{monadic procedures}.
6784 Consider this ``normal'' procedure:
6787 (define (sh-symlink store)
6788 ;; Return a derivation that symlinks the 'bash' executable.
6789 (let* ((drv (package-derivation store bash))
6790 (out (derivation->output-path drv))
6791 (sh (string-append out "/bin/bash")))
6792 (build-expression->derivation store "sh"
6793 `(symlink ,sh %output))))
6796 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
6797 as a monadic function:
6800 (define (sh-symlink)
6801 ;; Same, but return a monadic value.
6802 (mlet %store-monad ((drv (package->derivation bash)))
6803 (gexp->derivation "sh"
6804 #~(symlink (string-append #$drv "/bin/bash")
6808 There are several things to note in the second version: the @code{store}
6809 parameter is now implicit and is ``threaded'' in the calls to the
6810 @code{package->derivation} and @code{gexp->derivation} monadic
6811 procedures, and the monadic value returned by @code{package->derivation}
6812 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
6814 As it turns out, the call to @code{package->derivation} can even be
6815 omitted since it will take place implicitly, as we will see later
6816 (@pxref{G-Expressions}):
6819 (define (sh-symlink)
6820 (gexp->derivation "sh"
6821 #~(symlink (string-append #$bash "/bin/bash")
6826 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
6827 @c for the funny quote.
6828 Calling the monadic @code{sh-symlink} has no effect. As someone once
6829 said, ``you exit a monad like you exit a building on fire: by running''.
6830 So, to exit the monad and get the desired effect, one must use
6831 @code{run-with-store}:
6834 (run-with-store (open-connection) (sh-symlink))
6835 @result{} /gnu/store/...-sh-symlink
6838 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
6839 new ``meta-commands'' to make it easier to deal with monadic procedures:
6840 @code{run-in-store}, and @code{enter-store-monad}. The former is used
6841 to ``run'' a single monadic value through the store:
6844 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
6845 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6848 The latter enters a recursive REPL, where all the return values are
6849 automatically run through the store:
6852 scheme@@(guile-user)> ,enter-store-monad
6853 store-monad@@(guile-user) [1]> (package->derivation hello)
6854 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6855 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
6856 $3 = "/gnu/store/@dots{}-foo"
6857 store-monad@@(guile-user) [1]> ,q
6858 scheme@@(guile-user)>
6862 Note that non-monadic values cannot be returned in the
6863 @code{store-monad} REPL.
6865 The main syntactic forms to deal with monads in general are provided by
6866 the @code{(guix monads)} module and are described below.
6868 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
6869 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
6873 @deffn {Scheme Syntax} return @var{val}
6874 Return a monadic value that encapsulates @var{val}.
6877 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
6878 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
6879 procedures @var{mproc}@dots{}@footnote{This operation is commonly
6880 referred to as ``bind'', but that name denotes an unrelated procedure in
6881 Guile. Thus we use this somewhat cryptic symbol inherited from the
6882 Haskell language.}. There can be one @var{mproc} or several of them, as
6887 (with-monad %state-monad
6889 (lambda (x) (return (+ 1 x)))
6890 (lambda (x) (return (* 2 x)))))
6894 @result{} some-state
6898 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
6900 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
6902 Bind the variables @var{var} to the monadic values @var{mval} in
6903 @var{body}, which is a sequence of expressions. As with the bind
6904 operator, this can be thought of as ``unpacking'' the raw, non-monadic
6905 value ``contained'' in @var{mval} and making @var{var} refer to that
6906 raw, non-monadic value within the scope of the @var{body}. The form
6907 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
6908 @var{val}, as per @code{let}. The binding operations occur in sequence
6909 from left to right. The last expression of @var{body} must be a monadic
6910 expression, and its result will become the result of the @code{mlet} or
6911 @code{mlet*} when run in the @var{monad}.
6913 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
6914 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
6917 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
6918 Bind @var{mexp} and the following monadic expressions in sequence,
6919 returning the result of the last expression. Every expression in the
6920 sequence must be a monadic expression.
6922 This is akin to @code{mlet}, except that the return values of the
6923 monadic expressions are ignored. In that sense, it is analogous to
6924 @code{begin}, but applied to monadic expressions.
6927 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
6928 When @var{condition} is true, evaluate the sequence of monadic
6929 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6930 @var{condition} is false, return @code{*unspecified*} in the current
6931 monad. Every expression in the sequence must be a monadic expression.
6934 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
6935 When @var{condition} is false, evaluate the sequence of monadic
6936 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6937 @var{condition} is true, return @code{*unspecified*} in the current
6938 monad. Every expression in the sequence must be a monadic expression.
6942 The @code{(guix monads)} module provides the @dfn{state monad}, which
6943 allows an additional value---the state---to be @emph{threaded} through
6944 monadic procedure calls.
6946 @defvr {Scheme Variable} %state-monad
6947 The state monad. Procedures in the state monad can access and change
6948 the state that is threaded.
6950 Consider the example below. The @code{square} procedure returns a value
6951 in the state monad. It returns the square of its argument, but also
6952 increments the current state value:
6956 (mlet %state-monad ((count (current-state)))
6957 (mbegin %state-monad
6958 (set-current-state (+ 1 count))
6961 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
6966 When ``run'' through @var{%state-monad}, we obtain that additional state
6967 value, which is the number of @code{square} calls.
6970 @deffn {Monadic Procedure} current-state
6971 Return the current state as a monadic value.
6974 @deffn {Monadic Procedure} set-current-state @var{value}
6975 Set the current state to @var{value} and return the previous state as a
6979 @deffn {Monadic Procedure} state-push @var{value}
6980 Push @var{value} to the current state, which is assumed to be a list,
6981 and return the previous state as a monadic value.
6984 @deffn {Monadic Procedure} state-pop
6985 Pop a value from the current state and return it as a monadic value.
6986 The state is assumed to be a list.
6989 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
6990 Run monadic value @var{mval} starting with @var{state} as the initial
6991 state. Return two values: the resulting value, and the resulting state.
6994 The main interface to the store monad, provided by the @code{(guix
6995 store)} module, is as follows.
6997 @defvr {Scheme Variable} %store-monad
6998 The store monad---an alias for @var{%state-monad}.
7000 Values in the store monad encapsulate accesses to the store. When its
7001 effect is needed, a value of the store monad must be ``evaluated'' by
7002 passing it to the @code{run-with-store} procedure (see below.)
7005 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7006 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7007 open store connection.
7010 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7011 Return as a monadic value the absolute file name in the store of the file
7012 containing @var{text}, a string. @var{references} is a list of store items that the
7013 resulting text file refers to; it defaults to the empty list.
7016 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7017 Return as a monadic value the absolute file name in the store of the file
7018 containing @var{data}, a bytevector. @var{references} is a list of store
7019 items that the resulting binary file refers to; it defaults to the empty list.
7022 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7023 [#:recursive? #t] [#:select? (const #t)]
7024 Return the name of @var{file} once interned in the store. Use
7025 @var{name} as its store name, or the basename of @var{file} if
7026 @var{name} is omitted.
7028 When @var{recursive?} is true, the contents of @var{file} are added
7029 recursively; if @var{file} designates a flat file and @var{recursive?}
7030 is true, its contents are added, and its permission bits are kept.
7032 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7033 @var{stat})} for each directory entry, where @var{file} is the entry's
7034 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7035 entries for which @var{select?} does not return true.
7037 The example below adds a file to the store, under two different names:
7040 (run-with-store (open-connection)
7041 (mlet %store-monad ((a (interned-file "README"))
7042 (b (interned-file "README" "LEGU-MIN")))
7043 (return (list a b))))
7045 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7050 The @code{(guix packages)} module exports the following package-related
7053 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7054 [#:system (%current-system)] [#:target #f] @
7057 value in the absolute file name of @var{file} within the @var{output}
7058 directory of @var{package}. When @var{file} is omitted, return the name
7059 of the @var{output} directory of @var{package}. When @var{target} is
7060 true, use it as a cross-compilation target triplet.
7063 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7064 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7065 @var{target} [@var{system}]
7066 Monadic version of @code{package-derivation} and
7067 @code{package-cross-derivation} (@pxref{Defining Packages}).
7072 @section G-Expressions
7074 @cindex G-expression
7075 @cindex build code quoting
7076 So we have ``derivations'', which represent a sequence of build actions
7077 to be performed to produce an item in the store (@pxref{Derivations}).
7078 These build actions are performed when asking the daemon to actually
7079 build the derivations; they are run by the daemon in a container
7080 (@pxref{Invoking guix-daemon}).
7082 @cindex strata of code
7083 It should come as no surprise that we like to write these build actions
7084 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7085 code@footnote{The term @dfn{stratum} in this context was coined by
7086 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7087 Kiselyov, who has written insightful
7088 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7089 on this topic}, refers to this kind of code generation as
7090 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7091 to the daemon, etc.---and the ``build code''---code that actually
7092 performs build actions, such as making directories, invoking
7093 @command{make}, etc.
7095 To describe a derivation and its build actions, one typically needs to
7096 embed build code inside host code. It boils down to manipulating build
7097 code as data, and the homoiconicity of Scheme---code has a direct
7098 representation as data---comes in handy for that. But we need more than
7099 the normal @code{quasiquote} mechanism in Scheme to construct build
7102 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7103 S-expressions adapted to build expressions. G-expressions, or
7104 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7105 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7106 @code{#$}, and @code{#$@@}), which are comparable to
7107 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7108 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7109 GNU Guile Reference Manual}). However, there are major differences:
7113 Gexps are meant to be written to a file and run or manipulated by other
7117 When a high-level object such as a package or derivation is unquoted
7118 inside a gexp, the result is as if its output file name had been
7122 Gexps carry information about the packages or derivations they refer to,
7123 and these dependencies are automatically added as inputs to the build
7124 processes that use them.
7127 @cindex lowering, of high-level objects in gexps
7128 This mechanism is not limited to package and derivation
7129 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7130 derivations or files in the store can be defined,
7131 such that these objects can also be inserted
7132 into gexps. For example, a useful type of high-level objects that can be
7133 inserted in a gexp is ``file-like objects'', which make it easy to
7134 add files to the store and to refer to them in
7135 derivations and such (see @code{local-file} and @code{plain-file}
7138 To illustrate the idea, here is an example of a gexp:
7145 (symlink (string-append #$coreutils "/bin/ls")
7149 This gexp can be passed to @code{gexp->derivation}; we obtain a
7150 derivation that builds a directory containing exactly one symlink to
7151 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7154 (gexp->derivation "the-thing" build-exp)
7157 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7158 substituted to the reference to the @var{coreutils} package in the
7159 actual build code, and @var{coreutils} is automatically made an input to
7160 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7161 output)}) is replaced by a string containing the directory name of the
7162 output of the derivation.
7164 @cindex cross compilation
7165 In a cross-compilation context, it is useful to distinguish between
7166 references to the @emph{native} build of a package---that can run on the
7167 host---versus references to cross builds of a package. To that end, the
7168 @code{#+} plays the same role as @code{#$}, but is a reference to a
7169 native package build:
7172 (gexp->derivation "vi"
7175 (system* (string-append #+coreutils "/bin/ln")
7177 (string-append #$emacs "/bin/emacs")
7178 (string-append #$output "/bin/vi")))
7179 #:target "mips64el-linux-gnu")
7183 In the example above, the native build of @var{coreutils} is used, so
7184 that @command{ln} can actually run on the host; but then the
7185 cross-compiled build of @var{emacs} is referenced.
7187 @cindex imported modules, for gexps
7188 @findex with-imported-modules
7189 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7190 able to use certain Guile modules from the ``host environment'' in the
7191 gexp, so those modules should be imported in the ``build environment''.
7192 The @code{with-imported-modules} form allows you to express that:
7195 (let ((build (with-imported-modules '((guix build utils))
7197 (use-modules (guix build utils))
7198 (mkdir-p (string-append #$output "/bin"))))))
7199 (gexp->derivation "empty-dir"
7202 (display "success!\n")
7207 In this example, the @code{(guix build utils)} module is automatically
7208 pulled into the isolated build environment of our gexp, such that
7209 @code{(use-modules (guix build utils))} works as expected.
7211 @cindex module closure
7212 @findex source-module-closure
7213 Usually you want the @emph{closure} of the module to be imported---i.e.,
7214 the module itself and all the modules it depends on---rather than just
7215 the module; failing to do that, attempts to use the module will fail
7216 because of missing dependent modules. The @code{source-module-closure}
7217 procedure computes the closure of a module by looking at its source file
7218 headers, which comes in handy in this case:
7221 (use-modules (guix modules)) ;for 'source-module-closure'
7223 (with-imported-modules (source-module-closure
7224 '((guix build utils)
7226 (gexp->derivation "something-with-vms"
7228 (use-modules (guix build utils)
7233 @cindex extensions, for gexps
7234 @findex with-extensions
7235 In the same vein, sometimes you want to import not just pure-Scheme
7236 modules, but also ``extensions'' such as Guile bindings to C libraries
7237 or other ``full-blown'' packages. Say you need the @code{guile-json}
7238 package available on the build side, here's how you would do it:
7241 (use-modules (gnu packages guile)) ;for 'guile-json'
7243 (with-extensions (list guile-json)
7244 (gexp->derivation "something-with-json"
7246 (use-modules (json))
7250 The syntactic form to construct gexps is summarized below.
7252 @deffn {Scheme Syntax} #~@var{exp}
7253 @deffnx {Scheme Syntax} (gexp @var{exp})
7254 Return a G-expression containing @var{exp}. @var{exp} may contain one
7255 or more of the following forms:
7259 @itemx (ungexp @var{obj})
7260 Introduce a reference to @var{obj}. @var{obj} may have one of the
7261 supported types, for example a package or a
7262 derivation, in which case the @code{ungexp} form is replaced by its
7263 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7265 If @var{obj} is a list, it is traversed and references to supported
7266 objects are substituted similarly.
7268 If @var{obj} is another gexp, its contents are inserted and its
7269 dependencies are added to those of the containing gexp.
7271 If @var{obj} is another kind of object, it is inserted as is.
7273 @item #$@var{obj}:@var{output}
7274 @itemx (ungexp @var{obj} @var{output})
7275 This is like the form above, but referring explicitly to the
7276 @var{output} of @var{obj}---this is useful when @var{obj} produces
7277 multiple outputs (@pxref{Packages with Multiple Outputs}).
7280 @itemx #+@var{obj}:output
7281 @itemx (ungexp-native @var{obj})
7282 @itemx (ungexp-native @var{obj} @var{output})
7283 Same as @code{ungexp}, but produces a reference to the @emph{native}
7284 build of @var{obj} when used in a cross compilation context.
7286 @item #$output[:@var{output}]
7287 @itemx (ungexp output [@var{output}])
7288 Insert a reference to derivation output @var{output}, or to the main
7289 output when @var{output} is omitted.
7291 This only makes sense for gexps passed to @code{gexp->derivation}.
7294 @itemx (ungexp-splicing @var{lst})
7295 Like the above, but splices the contents of @var{lst} inside the
7299 @itemx (ungexp-native-splicing @var{lst})
7300 Like the above, but refers to native builds of the objects listed in
7305 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7306 of the @code{gexp?} type (see below.)
7309 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7310 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7311 in their execution environment.
7313 Each item in @var{modules} can be the name of a module, such as
7314 @code{(guix build utils)}, or it can be a module name, followed by an
7315 arrow, followed by a file-like object:
7318 `((guix build utils)
7320 ((guix config) => ,(scheme-file "config.scm"
7321 #~(define-module @dots{}))))
7325 In the example above, the first two modules are taken from the search
7326 path, and the last one is created from the given file-like object.
7328 This form has @emph{lexical} scope: it has an effect on the gexps
7329 directly defined in @var{body}@dots{}, but not on those defined, say, in
7330 procedures called from @var{body}@dots{}.
7333 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7334 Mark the gexps defined in @var{body}@dots{} as requiring
7335 @var{extensions} in their build and execution environment.
7336 @var{extensions} is typically a list of package objects such as those
7337 defined in the @code{(gnu packages guile)} module.
7339 Concretely, the packages listed in @var{extensions} are added to the
7340 load path while compiling imported modules in @var{body}@dots{}; they
7341 are also added to the load path of the gexp returned by
7345 @deffn {Scheme Procedure} gexp? @var{obj}
7346 Return @code{#t} if @var{obj} is a G-expression.
7349 G-expressions are meant to be written to disk, either as code building
7350 some derivation, or as plain files in the store. The monadic procedures
7351 below allow you to do that (@pxref{The Store Monad}, for more
7352 information about monads.)
7354 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7355 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7356 [#:hash #f] [#:hash-algo #f] @
7357 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7358 [#:module-path @var{%load-path}] @
7359 [#:effective-version "2.2"] @
7360 [#:references-graphs #f] [#:allowed-references #f] @
7361 [#:disallowed-references #f] @
7362 [#:leaked-env-vars #f] @
7363 [#:script-name (string-append @var{name} "-builder")] @
7364 [#:deprecation-warnings #f] @
7365 [#:local-build? #f] [#:substitutable? #t] @
7366 [#:properties '()] [#:guile-for-build #f]
7367 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7368 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7369 stored in a file called @var{script-name}. When @var{target} is true,
7370 it is used as the cross-compilation target triplet for packages referred
7373 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7375 make @var{modules} available in the evaluation context of @var{exp};
7376 @var{modules} is a list of names of Guile modules searched in
7377 @var{module-path} to be copied in the store, compiled, and made available in
7378 the load path during the execution of @var{exp}---e.g., @code{((guix
7379 build utils) (guix build gnu-build-system))}.
7381 @var{effective-version} determines the string to use when adding extensions of
7382 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7384 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7387 When @var{references-graphs} is true, it must be a list of tuples of one of the
7391 (@var{file-name} @var{package})
7392 (@var{file-name} @var{package} @var{output})
7393 (@var{file-name} @var{derivation})
7394 (@var{file-name} @var{derivation} @var{output})
7395 (@var{file-name} @var{store-item})
7398 The right-hand-side of each element of @var{references-graphs} is automatically made
7399 an input of the build process of @var{exp}. In the build environment, each
7400 @var{file-name} contains the reference graph of the corresponding item, in a simple
7403 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7404 In the latter case, the list denotes store items that the result is allowed to
7405 refer to. Any reference to another store item will lead to a build error.
7406 Similarly for @var{disallowed-references}, which can list items that must not be
7407 referenced by the outputs.
7409 @var{deprecation-warnings} determines whether to show deprecation warnings while
7410 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7412 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7415 @cindex file-like objects
7416 The @code{local-file}, @code{plain-file}, @code{computed-file},
7417 @code{program-file}, and @code{scheme-file} procedures below return
7418 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7419 these objects lead to a file in the store. Consider this G-expression:
7422 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7423 #$(local-file "/tmp/my-nscd.conf"))
7426 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7427 to the store. Once expanded, for instance @i{via}
7428 @code{gexp->derivation}, the G-expression refers to that copy under
7429 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7430 does not have any effect on what the G-expression does.
7431 @code{plain-file} can be used similarly; it differs in that the file
7432 content is directly passed as a string.
7434 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7435 [#:recursive? #f] [#:select? (const #t)]
7436 Return an object representing local file @var{file} to add to the store; this
7437 object can be used in a gexp. If @var{file} is a relative file name, it is looked
7438 up relative to the source file where this form appears. @var{file} will be added to
7439 the store under @var{name}--by default the base name of @var{file}.
7441 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7442 designates a flat file and @var{recursive?} is true, its contents are added, and its
7443 permission bits are kept.
7445 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7446 @var{stat})} for each directory entry, where @var{file} is the entry's
7447 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7448 entries for which @var{select?} does not return true.
7450 This is the declarative counterpart of the @code{interned-file} monadic
7451 procedure (@pxref{The Store Monad, @code{interned-file}}).
7454 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7455 Return an object representing a text file called @var{name} with the given
7456 @var{content} (a string or a bytevector) to be added to the store.
7458 This is the declarative counterpart of @code{text-file}.
7461 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7462 [#:options '(#:local-build? #t)]
7463 Return an object representing the store item @var{name}, a file or
7464 directory computed by @var{gexp}. @var{options}
7465 is a list of additional arguments to pass to @code{gexp->derivation}.
7467 This is the declarative counterpart of @code{gexp->derivation}.
7470 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7471 [#:guile (default-guile)] [#:module-path %load-path] @
7472 [#:system (%current-system)] [#:target #f]
7473 Return an executable script @var{name} that runs @var{exp} using
7474 @var{guile}, with @var{exp}'s imported modules in its search path.
7475 Look up @var{exp}'s modules in @var{module-path}.
7477 The example below builds a script that simply invokes the @command{ls}
7481 (use-modules (guix gexp) (gnu packages base))
7483 (gexp->script "list-files"
7484 #~(execl #$(file-append coreutils "/bin/ls")
7488 When ``running'' it through the store (@pxref{The Store Monad,
7489 @code{run-with-store}}), we obtain a derivation that produces an
7490 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7493 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7495 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7499 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7500 [#:guile #f] [#:module-path %load-path]
7501 Return an object representing the executable store item @var{name} that
7502 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7503 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7505 This is the declarative counterpart of @code{gexp->script}.
7508 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7509 [#:set-load-path? #t] [#:module-path %load-path] @
7511 [#:guile (default-guile)]
7512 Return a derivation that builds a file @var{name} containing @var{exp}.
7513 When @var{splice?} is true, @var{exp} is considered to be a list of
7514 expressions that will be spliced in the resulting file.
7516 When @var{set-load-path?} is true, emit code in the resulting file to
7517 set @code{%load-path} and @code{%load-compiled-path} to honor
7518 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7521 The resulting file holds references to all the dependencies of @var{exp}
7522 or a subset thereof.
7525 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7526 Return an object representing the Scheme file @var{name} that contains
7529 This is the declarative counterpart of @code{gexp->file}.
7532 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7533 Return as a monadic value a derivation that builds a text file
7534 containing all of @var{text}. @var{text} may list, in addition to
7535 strings, objects of any type that can be used in a gexp: packages,
7536 derivations, local file objects, etc. The resulting store file holds
7537 references to all these.
7539 This variant should be preferred over @code{text-file} anytime the file
7540 to create will reference items from the store. This is typically the
7541 case when building a configuration file that embeds store file names,
7545 (define (profile.sh)
7546 ;; Return the name of a shell script in the store that
7547 ;; initializes the 'PATH' environment variable.
7548 (text-file* "profile.sh"
7549 "export PATH=" coreutils "/bin:"
7550 grep "/bin:" sed "/bin\n"))
7553 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7554 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7555 preventing them from being garbage-collected during its lifetime.
7558 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7559 Return an object representing store file @var{name} containing
7560 @var{text}. @var{text} is a sequence of strings and file-like objects,
7564 (mixed-text-file "profile"
7565 "export PATH=" coreutils "/bin:" grep "/bin")
7568 This is the declarative counterpart of @code{text-file*}.
7571 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7572 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7573 Each item in @var{files} must be a two-element list where the first element is the
7574 file name to use in the new directory, and the second element is a gexp
7575 denoting the target file. Here's an example:
7579 `(("hosts" ,(plain-file "hosts"
7580 "127.0.0.1 localhost"))
7581 ("bashrc" ,(plain-file "bashrc"
7582 "alias ls='ls --color=auto'"))))
7585 This yields an @code{etc} directory containing these two files.
7588 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
7589 Return a directory that is the union of @var{things}, where @var{things} is a list of
7590 file-like objects denoting directories. For example:
7593 (directory-union "guile+emacs" (list guile emacs))
7596 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
7599 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
7600 Return a file-like object that expands to the concatenation of @var{obj}
7601 and @var{suffix}, where @var{obj} is a lowerable object and each
7602 @var{suffix} is a string.
7604 As an example, consider this gexp:
7607 (gexp->script "run-uname"
7608 #~(system* #$(file-append coreutils
7612 The same effect could be achieved with:
7615 (gexp->script "run-uname"
7616 #~(system* (string-append #$coreutils
7620 There is one difference though: in the @code{file-append} case, the
7621 resulting script contains the absolute file name as a string, whereas in
7622 the second case, the resulting script contains a @code{(string-append
7623 @dots{})} expression to construct the file name @emph{at run time}.
7627 Of course, in addition to gexps embedded in ``host'' code, there are
7628 also modules containing build tools. To make it clear that they are
7629 meant to be used in the build stratum, these modules are kept in the
7630 @code{(guix build @dots{})} name space.
7632 @cindex lowering, of high-level objects in gexps
7633 Internally, high-level objects are @dfn{lowered}, using their compiler,
7634 to either derivations or store items. For instance, lowering a package
7635 yields a derivation, and lowering a @code{plain-file} yields a store
7636 item. This is achieved using the @code{lower-object} monadic procedure.
7638 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
7640 Return as a value in @var{%store-monad} the derivation or store item
7641 corresponding to @var{obj} for @var{system}, cross-compiling for
7642 @var{target} if @var{target} is true. @var{obj} must be an object that
7643 has an associated gexp compiler, such as a @code{<package>}.
7646 @node Invoking guix repl
7647 @section Invoking @command{guix repl}
7649 @cindex REPL, read-eval-print loop
7650 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
7651 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
7652 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
7653 command, @command{guix repl} guarantees that all the Guix modules and all its
7654 dependencies are available in the search path. You can use it this way:
7658 scheme@@(guile-user)> ,use (gnu packages base)
7659 scheme@@(guile-user)> coreutils
7660 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
7664 In addition, @command{guix repl} implements a simple machine-readable REPL
7665 protocol for use by @code{(guix inferior)}, a facility to interact with
7666 @dfn{inferiors}, separate processes running a potentially different revision
7669 The available options are as follows:
7672 @item --type=@var{type}
7673 @itemx -t @var{type}
7674 Start a REPL of the given @var{TYPE}, which can be one of the following:
7678 This is default, and it spawns a standard full-featured Guile REPL.
7680 Spawn a REPL that uses the machine-readable protocol. This is the protocol
7681 that the @code{(guix inferior)} module speaks.
7684 @item --listen=@var{endpoint}
7685 By default, @command{guix repl} reads from standard input and writes to
7686 standard output. When this option is passed, it will instead listen for
7687 connections on @var{endpoint}. Here are examples of valid options:
7690 @item --listen=tcp:37146
7691 Accept connections on localhost on port 37146.
7693 @item --listen=unix:/tmp/socket
7694 Accept connections on the Unix-domain socket @file{/tmp/socket}.
7698 @c *********************************************************************
7702 This section describes Guix command-line utilities. Some of them are
7703 primarily targeted at developers and users who write new package
7704 definitions, while others are more generally useful. They complement
7705 the Scheme programming interface of Guix in a convenient way.
7708 * Invoking guix build:: Building packages from the command line.
7709 * Invoking guix edit:: Editing package definitions.
7710 * Invoking guix download:: Downloading a file and printing its hash.
7711 * Invoking guix hash:: Computing the cryptographic hash of a file.
7712 * Invoking guix import:: Importing package definitions.
7713 * Invoking guix refresh:: Updating package definitions.
7714 * Invoking guix lint:: Finding errors in package definitions.
7715 * Invoking guix size:: Profiling disk usage.
7716 * Invoking guix graph:: Visualizing the graph of packages.
7717 * Invoking guix publish:: Sharing substitutes.
7718 * Invoking guix challenge:: Challenging substitute servers.
7719 * Invoking guix copy:: Copying to and from a remote store.
7720 * Invoking guix container:: Process isolation.
7721 * Invoking guix weather:: Assessing substitute availability.
7722 * Invoking guix processes:: Listing client processes.
7725 @node Invoking guix build
7726 @section Invoking @command{guix build}
7728 @cindex package building
7729 @cindex @command{guix build}
7730 The @command{guix build} command builds packages or derivations and
7731 their dependencies, and prints the resulting store paths. Note that it
7732 does not modify the user's profile---this is the job of the
7733 @command{guix package} command (@pxref{Invoking guix package}). Thus,
7734 it is mainly useful for distribution developers.
7736 The general syntax is:
7739 guix build @var{options} @var{package-or-derivation}@dots{}
7742 As an example, the following command builds the latest versions of Emacs
7743 and of Guile, displays their build logs, and finally displays the
7744 resulting directories:
7747 guix build emacs guile
7750 Similarly, the following command builds all the available packages:
7753 guix build --quiet --keep-going \
7754 `guix package -A | cut -f1,2 --output-delimiter=@@`
7757 @var{package-or-derivation} may be either the name of a package found in
7758 the software distribution such as @code{coreutils} or
7759 @code{coreutils@@8.20}, or a derivation such as
7760 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
7761 package with the corresponding name (and optionally version) is searched
7762 for among the GNU distribution modules (@pxref{Package Modules}).
7764 Alternatively, the @code{--expression} option may be used to specify a
7765 Scheme expression that evaluates to a package; this is useful when
7766 disambiguating among several same-named packages or package variants is
7769 There may be zero or more @var{options}. The available options are
7770 described in the subsections below.
7773 * Common Build Options:: Build options for most commands.
7774 * Package Transformation Options:: Creating variants of packages.
7775 * Additional Build Options:: Options specific to 'guix build'.
7776 * Debugging Build Failures:: Real life packaging experience.
7779 @node Common Build Options
7780 @subsection Common Build Options
7782 A number of options that control the build process are common to
7783 @command{guix build} and other commands that can spawn builds, such as
7784 @command{guix package} or @command{guix archive}. These are the
7789 @item --load-path=@var{directory}
7790 @itemx -L @var{directory}
7791 Add @var{directory} to the front of the package module search path
7792 (@pxref{Package Modules}).
7794 This allows users to define their own packages and make them visible to
7795 the command-line tools.
7799 Keep the build tree of failed builds. Thus, if a build fails, its build
7800 tree is kept under @file{/tmp}, in a directory whose name is shown at
7801 the end of the build log. This is useful when debugging build issues.
7802 @xref{Debugging Build Failures}, for tips and tricks on how to debug
7805 This option has no effect when connecting to a remote daemon with a
7806 @code{guix://} URI (@pxref{The Store, the @code{GUIX_DAEMON_SOCKET}
7811 Keep going when some of the derivations fail to build; return only once
7812 all the builds have either completed or failed.
7814 The default behavior is to stop as soon as one of the specified
7815 derivations has failed.
7819 Do not build the derivations.
7821 @anchor{fallback-option}
7823 When substituting a pre-built binary fails, fall back to building
7824 packages locally (@pxref{Substitution Failure}).
7826 @item --substitute-urls=@var{urls}
7827 @anchor{client-substitute-urls}
7828 Consider @var{urls} the whitespace-separated list of substitute source
7829 URLs, overriding the default list of URLs of @command{guix-daemon}
7830 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
7832 This means that substitutes may be downloaded from @var{urls}, provided
7833 they are signed by a key authorized by the system administrator
7834 (@pxref{Substitutes}).
7836 When @var{urls} is the empty string, substitutes are effectively
7839 @item --no-substitutes
7840 Do not use substitutes for build products. That is, always build things
7841 locally instead of allowing downloads of pre-built binaries
7842 (@pxref{Substitutes}).
7845 Do not ``graft'' packages. In practice, this means that package updates
7846 available as grafts are not applied. @xref{Security Updates}, for more
7847 information on grafts.
7849 @item --rounds=@var{n}
7850 Build each derivation @var{n} times in a row, and raise an error if
7851 consecutive build results are not bit-for-bit identical.
7853 This is a useful way to detect non-deterministic builds processes.
7854 Non-deterministic build processes are a problem because they make it
7855 practically impossible for users to @emph{verify} whether third-party
7856 binaries are genuine. @xref{Invoking guix challenge}, for more.
7858 Note that, currently, the differing build results are not kept around,
7859 so you will have to manually investigate in case of an error---e.g., by
7860 stashing one of the build results with @code{guix archive --export}
7861 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
7864 @item --no-build-hook
7865 Do not attempt to offload builds @i{via} the ``build hook'' of the daemon
7866 (@pxref{Daemon Offload Setup}). That is, always build things locally
7867 instead of offloading builds to remote machines.
7869 @item --max-silent-time=@var{seconds}
7870 When the build or substitution process remains silent for more than
7871 @var{seconds}, terminate it and report a build failure.
7873 By default, the daemon's setting is honored (@pxref{Invoking
7874 guix-daemon, @code{--max-silent-time}}).
7876 @item --timeout=@var{seconds}
7877 Likewise, when the build or substitution process lasts for more than
7878 @var{seconds}, terminate it and report a build failure.
7880 By default, the daemon's setting is honored (@pxref{Invoking
7881 guix-daemon, @code{--timeout}}).
7883 @c Note: This option is actually not part of %standard-build-options but
7884 @c most programs honor it.
7885 @cindex verbosity, of the command-line tools
7886 @cindex build logs, verbosity
7887 @item -v @var{level}
7888 @itemx --verbosity=@var{level}
7889 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
7890 output is produced, 1 is for quiet output, and 2 shows all the build log
7891 output on standard error.
7893 @item --cores=@var{n}
7895 Allow the use of up to @var{n} CPU cores for the build. The special
7896 value @code{0} means to use as many CPU cores as available.
7898 @item --max-jobs=@var{n}
7900 Allow at most @var{n} build jobs in parallel. @xref{Invoking
7901 guix-daemon, @code{--max-jobs}}, for details about this option and the
7902 equivalent @command{guix-daemon} option.
7904 @item --debug=@var{level}
7905 Produce debugging output coming from the build daemon. @var{level} must be an
7906 integer between 0 and 5; higher means more verbose output. Setting a level of
7907 4 or more may be helpful when debugging setup issues with the build daemon.
7911 Behind the scenes, @command{guix build} is essentially an interface to
7912 the @code{package-derivation} procedure of the @code{(guix packages)}
7913 module, and to the @code{build-derivations} procedure of the @code{(guix
7914 derivations)} module.
7916 In addition to options explicitly passed on the command line,
7917 @command{guix build} and other @command{guix} commands that support
7918 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
7920 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
7921 Users can define this variable to a list of command line options that
7922 will automatically be used by @command{guix build} and other
7923 @command{guix} commands that can perform builds, as in the example
7927 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
7930 These options are parsed independently, and the result is appended to
7931 the parsed command-line options.
7935 @node Package Transformation Options
7936 @subsection Package Transformation Options
7938 @cindex package variants
7939 Another set of command-line options supported by @command{guix build}
7940 and also @command{guix package} are @dfn{package transformation
7941 options}. These are options that make it possible to define @dfn{package
7942 variants}---for instance, packages built from different source code.
7943 This is a convenient way to create customized packages on the fly
7944 without having to type in the definitions of package variants
7945 (@pxref{Defining Packages}).
7949 @item --with-source=@var{source}
7950 @itemx --with-source=@var{package}=@var{source}
7951 @itemx --with-source=@var{package}@@@var{version}=@var{source}
7952 Use @var{source} as the source of @var{package}, and @var{version} as
7954 @var{source} must be a file name or a URL, as for @command{guix
7955 download} (@pxref{Invoking guix download}).
7957 When @var{package} is omitted,
7958 it is taken to be the package name specified on the
7959 command line that matches the base of @var{source}---e.g.,
7960 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
7961 package is @code{guile}.
7963 Likewise, when @var{version} is omitted, the version string is inferred from
7964 @var{source}; in the previous example, it is @code{2.0.10}.
7966 This option allows users to try out versions of packages other than the
7967 one provided by the distribution. The example below downloads
7968 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
7969 the @code{ed} package:
7972 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
7975 As a developer, @code{--with-source} makes it easy to test release
7979 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
7982 @dots{} or to build from a checkout in a pristine environment:
7985 $ git clone git://git.sv.gnu.org/guix.git
7986 $ guix build guix --with-source=guix@@1.0=./guix
7989 @item --with-input=@var{package}=@var{replacement}
7990 Replace dependency on @var{package} by a dependency on
7991 @var{replacement}. @var{package} must be a package name, and
7992 @var{replacement} must be a package specification such as @code{guile}
7993 or @code{guile@@1.8}.
7995 For instance, the following command builds Guix, but replaces its
7996 dependency on the current stable version of Guile with a dependency on
7997 the legacy version of Guile, @code{guile@@2.0}:
8000 guix build --with-input=guile=guile@@2.0 guix
8003 This is a recursive, deep replacement. So in this example, both
8004 @code{guix} and its dependency @code{guile-json} (which also depends on
8005 @code{guile}) get rebuilt against @code{guile@@2.0}.
8007 This is implemented using the @code{package-input-rewriting} Scheme
8008 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8010 @item --with-graft=@var{package}=@var{replacement}
8011 This is similar to @code{--with-input} but with an important difference:
8012 instead of rebuilding the whole dependency chain, @var{replacement} is
8013 built and then @dfn{grafted} onto the binaries that were initially
8014 referring to @var{package}. @xref{Security Updates}, for more
8015 information on grafts.
8017 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8018 and all its dependencies, replacing references to the version of GnuTLS
8019 they currently refer to:
8022 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8025 This has the advantage of being much faster than rebuilding everything.
8026 But there is a caveat: it works if and only if @var{package} and
8027 @var{replacement} are strictly compatible---for example, if they provide
8028 a library, the application binary interface (ABI) of those libraries
8029 must be compatible. If @var{replacement} is somehow incompatible with
8030 @var{package}, then the resulting package may be unusable. Use with
8033 @item --with-git-url=@var{package}=@var{url}
8034 @cindex Git, using the latest commit
8035 @cindex latest commit, building
8036 Build @var{package} from the latest commit of the @code{master} branch of the
8037 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8040 For example, the following command builds the NumPy Python library against the
8041 latest commit of the master branch of Python itself:
8044 guix build python-numpy \
8045 --with-git-url=python=https://github.com/python/cpython
8048 This option can also be combined with @code{--with-branch} or
8049 @code{--with-commit} (see below).
8051 @cindex continuous integration
8052 Obviously, since it uses the latest commit of the given branch, the result of
8053 such a command varies over time. Nevertheless it is a convenient way to
8054 rebuild entire software stacks against the latest commit of one or more
8055 packages. This is particularly useful in the context of continuous
8058 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8059 consecutive accesses to the same repository. You may want to clean it up once
8060 in a while to save disk space.
8062 @item --with-branch=@var{package}=@var{branch}
8063 Build @var{package} from the latest commit of @var{branch}. If the
8064 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8065 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8066 repository URL is taken from that @code{source}. Otherwise you have to use
8067 @code{--with-git-url} to specify the URL of the Git repository.
8069 For instance, the following command builds @code{guile-sqlite3} from the
8070 latest commit of its @code{master} branch, and then builds @code{guix} (which
8071 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8072 specific @code{guile-sqlite3} build:
8075 guix build --with-branch=guile-sqlite3=master cuirass
8078 @item --with-commit=@var{package}=@var{commit}
8079 This is similar to @code{--with-branch}, except that it builds from
8080 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8081 Git commit SHA1 identifier or a tag.
8084 @node Additional Build Options
8085 @subsection Additional Build Options
8087 The command-line options presented below are specific to @command{guix
8094 Build quietly, without displaying the build log; this is equivalent to
8095 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8096 (or similar) and can always be retrieved using the @option{--log-file} option.
8098 @item --file=@var{file}
8099 @itemx -f @var{file}
8100 Build the package, derivation, or other file-like object that the code within
8101 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8103 As an example, @var{file} might contain a package definition like this
8104 (@pxref{Defining Packages}):
8107 @verbatiminclude package-hello.scm
8110 @item --expression=@var{expr}
8111 @itemx -e @var{expr}
8112 Build the package or derivation @var{expr} evaluates to.
8114 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8115 guile-1.8)}, which unambiguously designates this specific variant of
8116 version 1.8 of Guile.
8118 Alternatively, @var{expr} may be a G-expression, in which case it is used
8119 as a build program passed to @code{gexp->derivation}
8120 (@pxref{G-Expressions}).
8122 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8123 (@pxref{The Store Monad}). The procedure must return a derivation as a
8124 monadic value, which is then passed through @code{run-with-store}.
8128 Build the source derivations of the packages, rather than the packages
8131 For instance, @code{guix build -S gcc} returns something like
8132 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8135 The returned source tarball is the result of applying any patches and
8136 code snippets specified in the package @code{origin} (@pxref{Defining
8140 Fetch and return the source of @var{package-or-derivation} and all their
8141 dependencies, recursively. This is a handy way to obtain a local copy
8142 of all the source code needed to build @var{packages}, allowing you to
8143 eventually build them even without network access. It is an extension
8144 of the @code{--source} option and can accept one of the following
8145 optional argument values:
8149 This value causes the @code{--sources} option to behave in the same way
8150 as the @code{--source} option.
8153 Build the source derivations of all packages, including any source that
8154 might be listed as @code{inputs}. This is the default value.
8157 $ guix build --sources tzdata
8158 The following derivations will be built:
8159 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8160 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8164 Build the source derivations of all packages, as well of all transitive
8165 inputs to the packages. This can be used e.g.@: to
8166 prefetch package source for later offline building.
8169 $ guix build --sources=transitive tzdata
8170 The following derivations will be built:
8171 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8172 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8173 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8174 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8175 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8176 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8182 @item --system=@var{system}
8183 @itemx -s @var{system}
8184 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8185 the system type of the build host. The @command{guix build} command allows
8186 you to repeat this option several times, in which case it builds for all the
8187 specified systems; other commands ignore extraneous @option{-s} options.
8190 The @code{--system} flag is for @emph{native} compilation and must not
8191 be confused with cross-compilation. See @code{--target} below for
8192 information on cross-compilation.
8195 An example use of this is on Linux-based systems, which can emulate
8196 different personalities. For instance, passing
8197 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8198 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8199 to build packages in a complete 32-bit environment.
8202 Building for an @code{armhf-linux} system is unconditionally enabled on
8203 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8204 allow for this functionality, notably the ThunderX.
8207 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8208 is enabled (@pxref{Virtualization Services,
8209 @code{qemu-binfmt-service-type}}), you can build for any system for
8210 which a QEMU @code{binfmt_misc} handler is installed.
8212 Builds for a system other than that of the machine you are using can
8213 also be offloaded to a remote machine of the right architecture.
8214 @xref{Daemon Offload Setup}, for more information on offloading.
8216 @item --target=@var{triplet}
8217 @cindex cross-compilation
8218 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8219 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8220 configuration triplets,, autoconf, Autoconf}).
8222 @anchor{build-check}
8224 @cindex determinism, checking
8225 @cindex reproducibility, checking
8226 Rebuild @var{package-or-derivation}, which are already available in the
8227 store, and raise an error if the build results are not bit-for-bit
8230 This mechanism allows you to check whether previously installed
8231 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8232 of a package is deterministic. @xref{Invoking guix challenge}, for more
8233 background information and tools.
8235 When used in conjunction with @option{--keep-failed}, the differing
8236 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8237 This makes it easy to look for differences between the two results.
8240 @cindex repairing store items
8241 @cindex corruption, recovering from
8242 Attempt to repair the specified store items, if they are corrupt, by
8243 re-downloading or rebuilding them.
8245 This operation is not atomic and thus restricted to @code{root}.
8249 Return the derivation paths, not the output paths, of the given
8252 @item --root=@var{file}
8253 @itemx -r @var{file}
8254 @cindex GC roots, adding
8255 @cindex garbage collector roots, adding
8256 Make @var{file} a symlink to the result, and register it as a garbage
8259 Consequently, the results of this @command{guix build} invocation are
8260 protected from garbage collection until @var{file} is removed. When
8261 that option is omitted, build results are eligible for garbage
8262 collection as soon as the build completes. @xref{Invoking guix gc}, for
8266 @cindex build logs, access
8267 Return the build log file names or URLs for the given
8268 @var{package-or-derivation}, or raise an error if build logs are
8271 This works regardless of how packages or derivations are specified. For
8272 instance, the following invocations are equivalent:
8275 guix build --log-file `guix build -d guile`
8276 guix build --log-file `guix build guile`
8277 guix build --log-file guile
8278 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8281 If a log is unavailable locally, and unless @code{--no-substitutes} is
8282 passed, the command looks for a corresponding log on one of the
8283 substitute servers (as specified with @code{--substitute-urls}.)
8285 So for instance, imagine you want to see the build log of GDB on MIPS,
8286 but you are actually on an @code{x86_64} machine:
8289 $ guix build --log-file gdb -s mips64el-linux
8290 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8293 You can freely access a huge library of build logs!
8296 @node Debugging Build Failures
8297 @subsection Debugging Build Failures
8299 @cindex build failures, debugging
8300 When defining a new package (@pxref{Defining Packages}), you will
8301 probably find yourself spending some time debugging and tweaking the
8302 build until it succeeds. To do that, you need to operate the build
8303 commands yourself in an environment as close as possible to the one the
8306 To that end, the first thing to do is to use the @option{--keep-failed}
8307 or @option{-K} option of @command{guix build}, which will keep the
8308 failed build tree in @file{/tmp} or whatever directory you specified as
8309 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8311 From there on, you can @command{cd} to the failed build tree and source
8312 the @file{environment-variables} file, which contains all the
8313 environment variable definitions that were in place when the build
8314 failed. So let's say you're debugging a build failure in package
8315 @code{foo}; a typical session would look like this:
8319 @dots{} @i{build fails}
8320 $ cd /tmp/guix-build-foo.drv-0
8321 $ source ./environment-variables
8325 Now, you can invoke commands as if you were the daemon (almost) and
8326 troubleshoot your build process.
8328 Sometimes it happens that, for example, a package's tests pass when you
8329 run them manually but they fail when the daemon runs them. This can
8330 happen because the daemon runs builds in containers where, unlike in our
8331 environment above, network access is missing, @file{/bin/sh} does not
8332 exist, etc. (@pxref{Build Environment Setup}).
8334 In such cases, you may need to run inspect the build process from within
8335 a container similar to the one the build daemon creates:
8340 $ cd /tmp/guix-build-foo.drv-0
8341 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8342 [env]# source ./environment-variables
8346 Here, @command{guix environment -C} creates a container and spawns a new
8347 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8348 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8349 the container, which would may find handy while debugging. The
8350 @option{--no-grafts} option makes sure we get the exact same
8351 environment, with ungrafted packages (@pxref{Security Updates}, for more
8354 To get closer to a container like that used by the build daemon, we can
8355 remove @file{/bin/sh}:
8361 (Don't worry, this is harmless: this is all happening in the throw-away
8362 container created by @command{guix environment}.)
8364 The @command{strace} command is probably not in the search path, but we
8368 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8371 In this way, not only you will have reproduced the environment variables
8372 the daemon uses, you will also be running the build process in a container
8373 similar to the one the daemon uses.
8376 @node Invoking guix edit
8377 @section Invoking @command{guix edit}
8379 @cindex @command{guix edit}
8380 @cindex package definition, editing
8381 So many packages, so many source files! The @command{guix edit} command
8382 facilitates the life of users and packagers by pointing their editor at
8383 the source file containing the definition of the specified packages.
8387 guix edit gcc@@4.9 vim
8391 launches the program specified in the @code{VISUAL} or in the
8392 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8395 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8396 have created your own packages on @code{GUIX_PACKAGE_PATH}
8397 (@pxref{Package Modules}), you will be able to edit the package
8398 recipes. In other cases, you will be able to examine the read-only recipes
8399 for packages currently in the store.
8402 @node Invoking guix download
8403 @section Invoking @command{guix download}
8405 @cindex @command{guix download}
8406 @cindex downloading package sources
8407 When writing a package definition, developers typically need to download
8408 a source tarball, compute its SHA256 hash, and write that
8409 hash in the package definition (@pxref{Defining Packages}). The
8410 @command{guix download} tool helps with this task: it downloads a file
8411 from the given URI, adds it to the store, and prints both its file name
8412 in the store and its SHA256 hash.
8414 The fact that the downloaded file is added to the store saves bandwidth:
8415 when the developer eventually tries to build the newly defined package
8416 with @command{guix build}, the source tarball will not have to be
8417 downloaded again because it is already in the store. It is also a
8418 convenient way to temporarily stash files, which may be deleted
8419 eventually (@pxref{Invoking guix gc}).
8421 The @command{guix download} command supports the same URIs as used in
8422 package definitions. In particular, it supports @code{mirror://} URIs.
8423 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8424 Guile bindings for GnuTLS are available in the user's environment; when
8425 they are not available, an error is raised. @xref{Guile Preparations,
8426 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8427 GnuTLS-Guile}, for more information.
8429 @command{guix download} verifies HTTPS server certificates by loading
8430 the certificates of X.509 authorities from the directory pointed to by
8431 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8432 Certificates}), unless @option{--no-check-certificate} is used.
8434 The following options are available:
8437 @item --format=@var{fmt}
8439 Write the hash in the format specified by @var{fmt}. For more
8440 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8442 @item --no-check-certificate
8443 Do not validate the X.509 certificates of HTTPS servers.
8445 When using this option, you have @emph{absolutely no guarantee} that you
8446 are communicating with the authentic server responsible for the given
8447 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8449 @item --output=@var{file}
8450 @itemx -o @var{file}
8451 Save the downloaded file to @var{file} instead of adding it to the
8455 @node Invoking guix hash
8456 @section Invoking @command{guix hash}
8458 @cindex @command{guix hash}
8459 The @command{guix hash} command computes the SHA256 hash of a file.
8460 It is primarily a convenience tool for anyone contributing to the
8461 distribution: it computes the cryptographic hash of a file, which can be
8462 used in the definition of a package (@pxref{Defining Packages}).
8464 The general syntax is:
8467 guix hash @var{option} @var{file}
8470 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8471 hash of data read from standard input. @command{guix hash} has the
8476 @item --format=@var{fmt}
8478 Write the hash in the format specified by @var{fmt}.
8480 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8481 (@code{hex} and @code{hexadecimal} can be used as well).
8483 If the @option{--format} option is not specified, @command{guix hash}
8484 will output the hash in @code{nix-base32}. This representation is used
8485 in the definitions of packages.
8489 Compute the hash on @var{file} recursively.
8491 In this case, the hash is computed on an archive containing @var{file},
8492 including its children if it is a directory. Some of the metadata of
8493 @var{file} is part of the archive; for instance, when @var{file} is a
8494 regular file, the hash is different depending on whether @var{file} is
8495 executable or not. Metadata such as time stamps has no impact on the
8496 hash (@pxref{Invoking guix archive}).
8497 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8502 When combined with @option{--recursive}, exclude version control system
8503 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8506 As an example, here is how you would compute the hash of a Git checkout,
8507 which is useful when using the @code{git-fetch} method (@pxref{origin
8511 $ git clone http://example.org/foo.git
8517 @node Invoking guix import
8518 @section Invoking @command{guix import}
8520 @cindex importing packages
8521 @cindex package import
8522 @cindex package conversion
8523 @cindex Invoking @command{guix import}
8524 The @command{guix import} command is useful for people who would like to
8525 add a package to the distribution with as little work as
8526 possible---a legitimate demand. The command knows of a few
8527 repositories from which it can ``import'' package metadata. The result
8528 is a package definition, or a template thereof, in the format we know
8529 (@pxref{Defining Packages}).
8531 The general syntax is:
8534 guix import @var{importer} @var{options}@dots{}
8537 @var{importer} specifies the source from which to import package
8538 metadata, and @var{options} specifies a package identifier and other
8539 options specific to @var{importer}.
8541 Some of the importers rely on the ability to run the @command{gpgv} command.
8542 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
8545 Currently, the available ``importers'' are:
8549 Import metadata for the given GNU package. This provides a template
8550 for the latest version of that GNU package, including the hash of its
8551 source tarball, and its canonical synopsis and description.
8553 Additional information such as the package dependencies and its
8554 license needs to be figured out manually.
8556 For example, the following command returns a package definition for
8560 guix import gnu hello
8563 Specific command-line options are:
8566 @item --key-download=@var{policy}
8567 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
8568 keys when verifying the package signature. @xref{Invoking guix
8569 refresh, @code{--key-download}}.
8574 Import metadata from the @uref{https://pypi.python.org/, Python Package
8575 Index}. Information is taken from the JSON-formatted description
8576 available at @code{pypi.python.org} and usually includes all the relevant
8577 information, including package dependencies. For maximum efficiency, it
8578 is recommended to install the @command{unzip} utility, so that the
8579 importer can unzip Python wheels and gather data from them.
8581 The command below imports metadata for the @code{itsdangerous} Python
8585 guix import pypi itsdangerous
8591 Traverse the dependency graph of the given upstream package recursively
8592 and generate package expressions for all those packages that are not yet
8598 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
8599 is taken from the JSON-formatted description available at
8600 @code{rubygems.org} and includes most relevant information, including
8601 runtime dependencies. There are some caveats, however. The metadata
8602 doesn't distinguish between synopses and descriptions, so the same string
8603 is used for both fields. Additionally, the details of non-Ruby
8604 dependencies required to build native extensions is unavailable and left
8605 as an exercise to the packager.
8607 The command below imports metadata for the @code{rails} Ruby package:
8610 guix import gem rails
8616 Traverse the dependency graph of the given upstream package recursively
8617 and generate package expressions for all those packages that are not yet
8623 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
8624 Information is taken from the JSON-formatted metadata provided through
8625 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
8626 relevant information, such as module dependencies. License information
8627 should be checked closely. If Perl is available in the store, then the
8628 @code{corelist} utility will be used to filter core modules out of the
8629 list of dependencies.
8631 The command command below imports metadata for the @code{Acme::Boolean}
8635 guix import cpan Acme::Boolean
8640 @cindex Bioconductor
8641 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
8642 central repository for the @uref{https://r-project.org, GNU@tie{}R
8643 statistical and graphical environment}.
8645 Information is extracted from the @code{DESCRIPTION} file of the package.
8647 The command command below imports metadata for the @code{Cairo}
8651 guix import cran Cairo
8654 When @code{--recursive} is added, the importer will traverse the
8655 dependency graph of the given upstream package recursively and generate
8656 package expressions for all those packages that are not yet in Guix.
8658 When @code{--archive=bioconductor} is added, metadata is imported from
8659 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
8660 packages for for the analysis and comprehension of high-throughput
8661 genomic data in bioinformatics.
8663 Information is extracted from the @code{DESCRIPTION} file contained in the
8666 The command below imports metadata for the @code{GenomicRanges}
8670 guix import cran --archive=bioconductor GenomicRanges
8673 Finally, you can also import R packages that have not yet been published on
8674 CRAN or Bioconductor as long as they are in a git repository. Use
8675 @code{--archive=git} followed by the URL of the git repository:
8678 guix import cran --archive=git https://github.com/immunogenomics/harmony
8684 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
8685 comprehensive TeX archive network for TeX packages that are part of the
8686 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
8688 Information about the package is obtained through the XML API provided
8689 by CTAN, while the source code is downloaded from the SVN repository of
8690 the Tex Live project. This is done because the CTAN does not keep
8693 The command command below imports metadata for the @code{fontspec}
8697 guix import texlive fontspec
8700 When @code{--archive=DIRECTORY} is added, the source code is downloaded
8701 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
8702 tree in the TeX Live SVN repository, but from the specified sibling
8703 directory under the same root.
8705 The command below imports metadata for the @code{ifxetex} package from
8706 CTAN while fetching the sources from the directory
8707 @file{texmf/source/generic}:
8710 guix import texlive --archive=generic ifxetex
8714 @cindex JSON, import
8715 Import package metadata from a local JSON file. Consider the following
8716 example package definition in JSON format:
8722 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
8723 "build-system": "gnu",
8724 "home-page": "https://www.gnu.org/software/hello/",
8725 "synopsis": "Hello, GNU world: An example GNU package",
8726 "description": "GNU Hello prints a greeting.",
8727 "license": "GPL-3.0+",
8728 "native-inputs": ["gettext"]
8732 The field names are the same as for the @code{<package>} record
8733 (@xref{Defining Packages}). References to other packages are provided
8734 as JSON lists of quoted package specification strings such as
8735 @code{guile} or @code{guile@@2.0}.
8737 The importer also supports a more explicit source definition using the
8738 common fields for @code{<origin>} records:
8744 "method": "url-fetch",
8745 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
8747 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
8754 The command below reads metadata from the JSON file @code{hello.json}
8755 and outputs a package expression:
8758 guix import json hello.json
8762 Import metadata from a local copy of the source of the
8763 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
8764 relies on the @command{nix-instantiate} command of
8765 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
8766 typically written in a mixture of Nix-language and Bash code. This
8767 command only imports the high-level package structure that is written in
8768 the Nix language. It normally includes all the basic fields of a
8771 When importing a GNU package, the synopsis and descriptions are replaced
8772 by their canonical upstream variant.
8774 Usually, you will first need to do:
8777 export NIX_REMOTE=daemon
8781 so that @command{nix-instantiate} does not try to open the Nix database.
8783 As an example, the command below imports the package definition of
8784 LibreOffice (more precisely, it imports the definition of the package
8785 bound to the @code{libreoffice} top-level attribute):
8788 guix import nix ~/path/to/nixpkgs libreoffice
8793 Import metadata from the Haskell community's central package archive
8794 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
8795 Cabal files and includes all the relevant information, including package
8798 Specific command-line options are:
8803 Read a Cabal file from standard input.
8804 @item --no-test-dependencies
8806 Do not include dependencies required only by the test suites.
8807 @item --cabal-environment=@var{alist}
8808 @itemx -e @var{alist}
8809 @var{alist} is a Scheme alist defining the environment in which the
8810 Cabal conditionals are evaluated. The accepted keys are: @code{os},
8811 @code{arch}, @code{impl} and a string representing the name of a flag.
8812 The value associated with a flag has to be either the symbol
8813 @code{true} or @code{false}. The value associated with other keys
8814 has to conform to the Cabal file format definition. The default value
8815 associated with the keys @code{os}, @code{arch} and @code{impl} is
8816 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
8819 Traverse the dependency graph of the given upstream package recursively
8820 and generate package expressions for all those packages that are not yet
8824 The command below imports metadata for the latest version of the
8825 @code{HTTP} Haskell package without including test dependencies and
8826 specifying the value of the flag @samp{network-uri} as @code{false}:
8829 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
8832 A specific package version may optionally be specified by following the
8833 package name by an at-sign and a version number as in the following example:
8836 guix import hackage mtl@@2.1.3.1
8841 The @code{stackage} importer is a wrapper around the @code{hackage} one.
8842 It takes a package name, looks up the package version included in a
8843 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
8844 release and uses the @code{hackage} importer to retrieve its metadata.
8845 Note that it is up to you to select an LTS release compatible with the
8846 GHC compiler used by Guix.
8848 Specific command-line options are:
8851 @item --no-test-dependencies
8853 Do not include dependencies required only by the test suites.
8854 @item --lts-version=@var{version}
8855 @itemx -l @var{version}
8856 @var{version} is the desired LTS release version. If omitted the latest
8860 Traverse the dependency graph of the given upstream package recursively
8861 and generate package expressions for all those packages that are not yet
8865 The command below imports metadata for the @code{HTTP} Haskell package
8866 included in the LTS Stackage release version 7.18:
8869 guix import stackage --lts-version=7.18 HTTP
8874 Import metadata from an Emacs Lisp Package Archive (ELPA) package
8875 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
8877 Specific command-line options are:
8880 @item --archive=@var{repo}
8881 @itemx -a @var{repo}
8882 @var{repo} identifies the archive repository from which to retrieve the
8883 information. Currently the supported repositories and their identifiers
8887 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
8888 identifier. This is the default.
8890 Packages from @code{elpa.gnu.org} are signed with one of the keys
8891 contained in the GnuPG keyring at
8892 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
8893 @code{emacs} package (@pxref{Package Installation, ELPA package
8894 signatures,, emacs, The GNU Emacs Manual}).
8897 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
8898 @code{melpa-stable} identifier.
8901 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
8907 Traverse the dependency graph of the given upstream package recursively
8908 and generate package expressions for all those packages that are not yet
8914 Import metadata from the crates.io Rust package repository
8915 @uref{https://crates.io, crates.io}.
8920 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
8921 repository used by the OCaml community.
8924 The structure of the @command{guix import} code is modular. It would be
8925 useful to have more importers for other package formats, and your help
8926 is welcome here (@pxref{Contributing}).
8928 @node Invoking guix refresh
8929 @section Invoking @command{guix refresh}
8931 @cindex @command {guix refresh}
8932 The primary audience of the @command{guix refresh} command is developers
8933 of the GNU software distribution. By default, it reports any packages
8934 provided by the distribution that are outdated compared to the latest
8935 upstream version, like this:
8939 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
8940 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
8943 Alternately, one can specify packages to consider, in which case a
8944 warning is emitted for packages that lack an updater:
8947 $ guix refresh coreutils guile guile-ssh
8948 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
8949 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
8952 @command{guix refresh} browses the upstream repository of each package and determines
8953 the highest version number of the releases therein. The command
8954 knows how to update specific types of packages: GNU packages, ELPA
8955 packages, etc.---see the documentation for @option{--type} below. There
8956 are many packages, though, for which it lacks a method to determine
8957 whether a new upstream release is available. However, the mechanism is
8958 extensible, so feel free to get in touch with us to add a new method!
8963 Consider the packages specified, and all the packages upon which they depend.
8966 $ guix refresh --recursive coreutils
8967 gnu/packages/acl.scm:35:2: warning: no updater for acl
8968 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
8969 gnu/packages/xml.scm:68:2: warning: no updater for expat
8970 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
8976 Sometimes the upstream name differs from the package name used in Guix,
8977 and @command{guix refresh} needs a little help. Most updaters honor the
8978 @code{upstream-name} property in package definitions, which can be used
8982 (define-public network-manager
8984 (name "network-manager")
8986 (properties '((upstream-name . "NetworkManager")))))
8989 When passed @code{--update}, it modifies distribution source files to
8990 update the version numbers and source tarball hashes of those package
8991 recipes (@pxref{Defining Packages}). This is achieved by downloading
8992 each package's latest source tarball and its associated OpenPGP
8993 signature, authenticating the downloaded tarball against its signature
8994 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
8995 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
8998 key used to sign the tarball is missing from the user's keyring, an
8999 attempt is made to automatically retrieve it from a public key server;
9000 when this is successful, the key is added to the user's keyring; otherwise,
9001 @command{guix refresh} reports an error.
9003 The following options are supported:
9007 @item --expression=@var{expr}
9008 @itemx -e @var{expr}
9009 Consider the package @var{expr} evaluates to.
9011 This is useful to precisely refer to a package, as in this example:
9014 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9017 This command lists the dependents of the ``final'' libc (essentially all
9022 Update distribution source files (package recipes) in place. This is
9023 usually run from a checkout of the Guix source tree (@pxref{Running
9024 Guix Before It Is Installed}):
9027 $ ./pre-inst-env guix refresh -s non-core -u
9030 @xref{Defining Packages}, for more information on package definitions.
9032 @item --select=[@var{subset}]
9033 @itemx -s @var{subset}
9034 Select all the packages in @var{subset}, one of @code{core} or
9037 The @code{core} subset refers to all the packages at the core of the
9038 distribution---i.e., packages that are used to build ``everything
9039 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9040 changing one of these packages in the distribution entails a rebuild of
9041 all the others. Thus, such updates are an inconvenience to users in
9042 terms of build time or bandwidth used to achieve the upgrade.
9044 The @code{non-core} subset refers to the remaining packages. It is
9045 typically useful in cases where an update of the core packages would be
9048 @item --manifest=@var{file}
9049 @itemx -m @var{file}
9050 Select all the packages from the manifest in @var{file}. This is useful to
9051 check if any packages of the user manifest can be updated.
9053 @item --type=@var{updater}
9054 @itemx -t @var{updater}
9055 Select only packages handled by @var{updater} (may be a comma-separated
9056 list of updaters). Currently, @var{updater} may be one of:
9060 the updater for GNU packages;
9062 the updater for GNOME packages;
9064 the updater for KDE packages;
9066 the updater for X.org packages;
9068 the updater for packages hosted on kernel.org;
9070 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9072 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9074 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9076 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9078 the updater for @uref{https://pypi.python.org, PyPI} packages.
9080 the updater for @uref{https://rubygems.org, RubyGems} packages.
9082 the updater for @uref{https://github.com, GitHub} packages.
9084 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9086 the updater for @uref{https://www.stackage.org, Stackage} packages.
9088 the updater for @uref{https://crates.io, Crates} packages.
9090 the updater for @uref{https://launchpad.net, Launchpad} packages.
9093 For instance, the following command only checks for updates of Emacs
9094 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9097 $ guix refresh --type=elpa,cran
9098 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9099 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9104 In addition, @command{guix refresh} can be passed one or more package
9105 names, as in this example:
9108 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9112 The command above specifically updates the @code{emacs} and
9113 @code{idutils} packages. The @code{--select} option would have no
9114 effect in this case.
9116 When considering whether to upgrade a package, it is sometimes
9117 convenient to know which packages would be affected by the upgrade and
9118 should be checked for compatibility. For this the following option may
9119 be used when passing @command{guix refresh} one or more package names:
9123 @item --list-updaters
9125 List available updaters and exit (see @option{--type} above.)
9127 For each updater, display the fraction of packages it covers; at the
9128 end, display the fraction of packages covered by all these updaters.
9130 @item --list-dependent
9132 List top-level dependent packages that would need to be rebuilt as a
9133 result of upgrading one or more packages.
9135 @xref{Invoking guix graph, the @code{reverse-package} type of
9136 @command{guix graph}}, for information on how to visualize the list of
9137 dependents of a package.
9141 Be aware that the @code{--list-dependent} option only
9142 @emph{approximates} the rebuilds that would be required as a result of
9143 an upgrade. More rebuilds might be required under some circumstances.
9146 $ guix refresh --list-dependent flex
9147 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9148 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9151 The command above lists a set of packages that could be built to check
9152 for compatibility with an upgraded @code{flex} package.
9156 @item --list-transitive
9157 List all the packages which one or more packages depend upon.
9160 $ guix refresh --list-transitive flex
9161 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9162 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{}
9167 The command above lists a set of packages which, when changed, would cause
9168 @code{flex} to be rebuilt.
9170 The following options can be used to customize GnuPG operation:
9174 @item --gpg=@var{command}
9175 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9176 for in @code{$PATH}.
9178 @item --keyring=@var{file}
9179 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9180 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9181 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9182 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9183 information on a tool to manipulate keybox files).
9185 When this option is omitted, @command{guix refresh} uses
9186 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9187 signing keys. OpenPGP signatures are checked against keys from this keyring;
9188 missing keys are downloaded to this keyring as well (see
9189 @option{--key-download} below.)
9191 You can export keys from your default GPG keyring into a keybox file using
9192 commands like this one:
9195 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9198 Likewise, you can fetch keys to a specific keybox file like this:
9201 gpg --no-default-keyring --keyring mykeyring.kbx \
9202 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9205 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9206 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9208 @item --key-download=@var{policy}
9209 Handle missing OpenPGP keys according to @var{policy}, which may be one
9214 Always download missing OpenPGP keys from the key server, and add them
9215 to the user's GnuPG keyring.
9218 Never try to download missing OpenPGP keys. Instead just bail out.
9221 When a package signed with an unknown OpenPGP key is encountered, ask
9222 the user whether to download it or not. This is the default behavior.
9225 @item --key-server=@var{host}
9226 Use @var{host} as the OpenPGP key server when importing a public key.
9230 The @code{github} updater uses the
9231 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9232 releases. When used repeatedly e.g.@: when refreshing all packages,
9233 GitHub will eventually refuse to answer any further API requests. By
9234 default 60 API requests per hour are allowed, and a full refresh on all
9235 GitHub packages in Guix requires more than this. Authentication with
9236 GitHub through the use of an API token alleviates these limits. To use
9237 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9238 token procured from @uref{https://github.com/settings/tokens} or
9242 @node Invoking guix lint
9243 @section Invoking @command{guix lint}
9245 @cindex @command{guix lint}
9246 @cindex package, checking for errors
9247 The @command{guix lint} command is meant to help package developers avoid
9248 common errors and use a consistent style. It runs a number of checks on
9249 a given set of packages in order to find common mistakes in their
9250 definitions. Available @dfn{checkers} include (see
9251 @code{--list-checkers} for a complete list):
9256 Validate certain typographical and stylistic rules about package
9257 descriptions and synopses.
9259 @item inputs-should-be-native
9260 Identify inputs that should most likely be native inputs.
9266 @itemx source-file-name
9267 Probe @code{home-page} and @code{source} URLs and report those that are
9268 invalid. Suggest a @code{mirror://} URL when applicable. If the
9269 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9270 URL. Check that the source file name is meaningful, e.g.@: is not just a
9271 version number or ``git-checkout'', without a declared @code{file-name}
9272 (@pxref{origin Reference}).
9274 @item source-unstable-tarball
9275 Parse the @code{source} URL to determine if a tarball from GitHub is
9276 autogenerated or if it is a release tarball. Unfortunately GitHub's
9277 autogenerated tarballs are sometimes regenerated.
9280 @cindex Software Heritage, source code archive
9281 @cindex archival of source code, Software Heritage
9282 Checks whether the package's source code is archived at
9283 @uref{https://www.softwareheritage.org, Software Heritage}.
9285 When the source code that is not archived comes from a version-control system
9286 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
9287 ``save'' request so that it eventually archives it. This ensures that the
9288 source will remain available in the long term, and that Guix can fall back to
9289 Software Heritage should the source code disappear from its original host.
9290 The status of recent ``save'' requests can be
9291 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
9293 When source code is a tarball obtained with @code{url-fetch}, simply print a
9294 message when it is not archived. As of this writing, Software Heritage does
9295 not allow requests to save arbitrary tarballs; we are working on ways to
9296 ensure that non-VCS source code is also archived.
9299 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
9300 request rate per IP address}. When the limit is reached, @command{guix lint}
9301 prints a message and the @code{archival} checker stops doing anything until
9302 that limit has been reset.
9305 @cindex security vulnerabilities
9306 @cindex CVE, Common Vulnerabilities and Exposures
9307 Report known vulnerabilities found in the Common Vulnerabilities and
9308 Exposures (CVE) databases of the current and past year
9309 @uref{https://nvd.nist.gov/download.cfm#CVE_FEED, published by the US
9312 To view information about a particular vulnerability, visit pages such as:
9316 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9318 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9322 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9323 @code{CVE-2015-7554}.
9325 Package developers can specify in package recipes the
9326 @uref{https://nvd.nist.gov/cpe.cfm,Common Platform Enumeration (CPE)}
9327 name and version of the package when they differ from the name or version
9328 that Guix uses, as in this example:
9334 ;; CPE calls this package "grub2".
9335 (properties '((cpe-name . "grub2")
9336 (cpe-version . "2.3")))
9339 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9340 Some entries in the CVE database do not specify which version of a
9341 package they apply to, and would thus ``stick around'' forever. Package
9342 developers who found CVE alerts and verified they can be ignored can
9343 declare them as in this example:
9349 ;; These CVEs no longer apply and can be safely ignored.
9350 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9353 "CVE-2011-5244")))))
9357 Warn about obvious source code formatting issues: trailing white space,
9358 use of tabulations, etc.
9361 The general syntax is:
9364 guix lint @var{options} @var{package}@dots{}
9367 If no package is given on the command line, then all packages are checked.
9368 The @var{options} may be zero or more of the following:
9371 @item --list-checkers
9373 List and describe all the available checkers that will be run on packages
9378 Only enable the checkers specified in a comma-separated list using the
9379 names returned by @code{--list-checkers}.
9383 @node Invoking guix size
9384 @section Invoking @command{guix size}
9387 @cindex package size
9389 @cindex @command{guix size}
9390 The @command{guix size} command helps package developers profile the
9391 disk usage of packages. It is easy to overlook the impact of an
9392 additional dependency added to a package, or the impact of using a
9393 single output for a package that could easily be split (@pxref{Packages
9394 with Multiple Outputs}). Such are the typical issues that
9395 @command{guix size} can highlight.
9397 The command can be passed one or more package specifications
9398 such as @code{gcc@@4.8}
9399 or @code{guile:debug}, or a file name in the store. Consider this
9403 $ guix size coreutils
9404 store item total self
9405 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9406 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9407 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9408 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9409 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9410 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9411 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9412 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9417 The store items listed here constitute the @dfn{transitive closure} of
9418 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9419 would be returned by:
9422 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9425 Here the output shows three columns next to store items. The first column,
9426 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9427 the store item---that is, its own size plus the size of all its
9428 dependencies. The next column, labeled ``self'', shows the size of the
9429 item itself. The last column shows the ratio of the size of the item
9430 itself to the space occupied by all the items listed here.
9432 In this example, we see that the closure of Coreutils weighs in at
9433 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9434 libraries. (That libc and GCC's libraries represent a large fraction of
9435 the closure is not a problem @i{per se} because they are always available
9436 on the system anyway.)
9438 When the package(s) passed to @command{guix size} are available in the
9439 store@footnote{More precisely, @command{guix size} looks for the
9440 @emph{ungrafted} variant of the given package(s), as returned by
9441 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9442 for information on grafts.}, @command{guix size} queries the daemon to determine its
9443 dependencies, and measures its size in the store, similar to @command{du
9444 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9447 When the given packages are @emph{not} in the store, @command{guix size}
9448 reports information based on the available substitutes
9449 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9450 store items that are not even on disk, only available remotely.
9452 You can also specify several package names:
9455 $ guix size coreutils grep sed bash
9456 store item total self
9457 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9458 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9459 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9460 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9466 In this example we see that the combination of the four packages takes
9467 102.3@tie{}MiB in total, which is much less than the sum of each closure
9468 since they have a lot of dependencies in common.
9470 The available options are:
9474 @item --substitute-urls=@var{urls}
9475 Use substitute information from @var{urls}.
9476 @xref{client-substitute-urls, the same option for @code{guix build}}.
9478 @item --sort=@var{key}
9479 Sort lines according to @var{key}, one of the following options:
9483 the size of each item (the default);
9485 the total size of the item's closure.
9488 @item --map-file=@var{file}
9489 Write a graphical map of disk usage in PNG format to @var{file}.
9491 For the example above, the map looks like this:
9493 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
9494 produced by @command{guix size}}
9496 This option requires that
9497 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
9498 installed and visible in Guile's module search path. When that is not
9499 the case, @command{guix size} fails as it tries to load it.
9501 @item --system=@var{system}
9502 @itemx -s @var{system}
9503 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
9507 @node Invoking guix graph
9508 @section Invoking @command{guix graph}
9511 @cindex @command{guix graph}
9512 @cindex package dependencies
9513 Packages and their dependencies form a @dfn{graph}, specifically a
9514 directed acyclic graph (DAG). It can quickly become difficult to have a
9515 mental model of the package DAG, so the @command{guix graph} command
9516 provides a visual representation of the DAG. By default,
9517 @command{guix graph} emits a DAG representation in the input format of
9518 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
9519 directly to the @command{dot} command of Graphviz. It can also emit an
9520 HTML page with embedded JavaScript code to display a ``chord diagram''
9521 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
9522 emit Cypher queries to construct a graph in a graph database supporting
9523 the @uref{https://www.opencypher.org/, openCypher} query language.
9524 The general syntax is:
9527 guix graph @var{options} @var{package}@dots{}
9530 For example, the following command generates a PDF file representing the
9531 package DAG for the GNU@tie{}Core Utilities, showing its build-time
9535 guix graph coreutils | dot -Tpdf > dag.pdf
9538 The output looks like this:
9540 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
9542 Nice little graph, no?
9544 But there is more than one graph! The one above is concise: it is the
9545 graph of package objects, omitting implicit inputs such as GCC, libc,
9546 grep, etc. It is often useful to have such a concise graph, but
9547 sometimes one may want to see more details. @command{guix graph} supports
9548 several types of graphs, allowing you to choose the level of detail:
9552 This is the default type used in the example above. It shows the DAG of
9553 package objects, excluding implicit dependencies. It is concise, but
9554 filters out many details.
9556 @item reverse-package
9557 This shows the @emph{reverse} DAG of packages. For example:
9560 guix graph --type=reverse-package ocaml
9563 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
9564 you are also interested in cases where OCaml is an implicit dependency, see
9565 @code{reverse-bag} below.)
9567 Note that for core packages this can yield huge graphs. If all you want
9568 is to know the number of packages that depend on a given package, use
9569 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
9570 @option{--list-dependent}}).
9573 This is the package DAG, @emph{including} implicit inputs.
9575 For instance, the following command:
9578 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
9581 ...@: yields this bigger graph:
9583 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
9585 At the bottom of the graph, we see all the implicit inputs of
9586 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
9588 Now, note that the dependencies of these implicit inputs---that is, the
9589 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
9590 here, for conciseness.
9593 Similar to @code{bag-emerged}, but this time including all the bootstrap
9596 @item bag-with-origins
9597 Similar to @code{bag}, but also showing origins and their dependencies.
9600 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
9601 it also takes implicit dependencies into account. For example:
9604 guix graph -t reverse-bag dune
9608 ...@: yields the graph of all packages that depend on Dune, directly or
9609 indirectly. Since Dune is an @emph{implicit} dependency of many packages
9610 @i{via} @code{dune-build-system}, this shows a large number of packages,
9611 whereas @code{reverse-package} would show very few if any.
9614 This is the most detailed representation: It shows the DAG of
9615 derivations (@pxref{Derivations}) and plain store items. Compared to
9616 the above representation, many additional nodes are visible, including
9617 build scripts, patches, Guile modules, etc.
9619 For this type of graph, it is also possible to pass a @file{.drv} file
9620 name instead of a package name, as in:
9623 guix graph -t derivation `guix system build -d my-config.scm`
9627 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
9628 For example, the following command shows the graph for the package
9629 module that defines the @code{guile} package:
9632 guix graph -t module guile | dot -Tpdf > module-graph.pdf
9636 All the types above correspond to @emph{build-time dependencies}. The
9637 following graph type represents the @emph{run-time dependencies}:
9641 This is the graph of @dfn{references} of a package output, as returned
9642 by @command{guix gc --references} (@pxref{Invoking guix gc}).
9644 If the given package output is not available in the store, @command{guix
9645 graph} attempts to obtain dependency information from substitutes.
9647 Here you can also pass a store file name instead of a package name. For
9648 example, the command below produces the reference graph of your profile
9649 (which can be big!):
9652 guix graph -t references `readlink -f ~/.guix-profile`
9656 This is the graph of the @dfn{referrers} of a store item, as returned by
9657 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
9659 This relies exclusively on local information from your store. For
9660 instance, let us suppose that the current Inkscape is available in 10
9661 profiles on your machine; @command{guix graph -t referrers inkscape}
9662 will show a graph rooted at Inkscape and with those 10 profiles linked
9665 It can help determine what is preventing a store item from being garbage
9670 The available options are the following:
9673 @item --type=@var{type}
9674 @itemx -t @var{type}
9675 Produce a graph output of @var{type}, where @var{type} must be one of
9676 the values listed above.
9679 List the supported graph types.
9681 @item --backend=@var{backend}
9682 @itemx -b @var{backend}
9683 Produce a graph using the selected @var{backend}.
9685 @item --list-backends
9686 List the supported graph backends.
9688 Currently, the available backends are Graphviz and d3.js.
9690 @item --expression=@var{expr}
9691 @itemx -e @var{expr}
9692 Consider the package @var{expr} evaluates to.
9694 This is useful to precisely refer to a package, as in this example:
9697 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
9700 @item --system=@var{system}
9701 @itemx -s @var{system}
9702 Display the graph for @var{system}---e.g., @code{i686-linux}.
9704 The package dependency graph is largely architecture-independent, but there
9705 are some architecture-dependent bits that this option allows you to visualize.
9710 @node Invoking guix publish
9711 @section Invoking @command{guix publish}
9713 @cindex @command{guix publish}
9714 The purpose of @command{guix publish} is to enable users to easily share
9715 their store with others, who can then use it as a substitute server
9716 (@pxref{Substitutes}).
9718 When @command{guix publish} runs, it spawns an HTTP server which allows
9719 anyone with network access to obtain substitutes from it. This means
9720 that any machine running Guix can also act as if it were a build farm,
9721 since the HTTP interface is compatible with Cuirass, the software behind
9722 the @code{@value{SUBSTITUTE-SERVER}} build farm.
9724 For security, each substitute is signed, allowing recipients to check
9725 their authenticity and integrity (@pxref{Substitutes}). Because
9726 @command{guix publish} uses the signing key of the system, which is only
9727 readable by the system administrator, it must be started as root; the
9728 @code{--user} option makes it drop root privileges early on.
9730 The signing key pair must be generated before @command{guix publish} is
9731 launched, using @command{guix archive --generate-key} (@pxref{Invoking
9734 The general syntax is:
9737 guix publish @var{options}@dots{}
9740 Running @command{guix publish} without any additional arguments will
9741 spawn an HTTP server on port 8080:
9747 Once a publishing server has been authorized (@pxref{Invoking guix
9748 archive}), the daemon may download substitutes from it:
9751 guix-daemon --substitute-urls=http://example.org:8080
9754 By default, @command{guix publish} compresses archives on the fly as it
9755 serves them. This ``on-the-fly'' mode is convenient in that it requires
9756 no setup and is immediately available. However, when serving lots of
9757 clients, we recommend using the @option{--cache} option, which enables
9758 caching of the archives before they are sent to clients---see below for
9759 details. The @command{guix weather} command provides a handy way to
9760 check what a server provides (@pxref{Invoking guix weather}).
9762 As a bonus, @command{guix publish} also serves as a content-addressed
9763 mirror for source files referenced in @code{origin} records
9764 (@pxref{origin Reference}). For instance, assuming @command{guix
9765 publish} is running on @code{example.org}, the following URL returns the
9766 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
9767 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
9770 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
9773 Obviously, these URLs only work for files that are in the store; in
9774 other cases, they return 404 (``Not Found'').
9776 @cindex build logs, publication
9777 Build logs are available from @code{/log} URLs like:
9780 http://example.org/log/gwspk@dots{}-guile-2.2.3
9784 When @command{guix-daemon} is configured to save compressed build logs,
9785 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
9786 URLs return the compressed log as-is, with an appropriate
9787 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
9788 running @command{guix-daemon} with @code{--log-compression=gzip} since
9789 Web browsers can automatically decompress it, which is not the case with
9792 The following options are available:
9795 @item --port=@var{port}
9796 @itemx -p @var{port}
9797 Listen for HTTP requests on @var{port}.
9799 @item --listen=@var{host}
9800 Listen on the network interface for @var{host}. The default is to
9801 accept connections from any interface.
9803 @item --user=@var{user}
9804 @itemx -u @var{user}
9805 Change privileges to @var{user} as soon as possible---i.e., once the
9806 server socket is open and the signing key has been read.
9808 @item --compression[=@var{method}[:@var{level}]]
9809 @itemx -C [@var{method}[:@var{level}]]
9810 Compress data using the given @var{method} and @var{level}. @var{method} is
9811 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
9814 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
9815 to different compression levels: 1 is the fastest, and 9 is the best
9816 (CPU-intensive). The default is 3.
9818 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
9819 increase in CPU usage; see
9820 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
9823 Unless @option{--cache} is used, compression occurs on the fly and
9824 the compressed streams are not
9825 cached. Thus, to reduce load on the machine that runs @command{guix
9826 publish}, it may be a good idea to choose a low compression level, to
9827 run @command{guix publish} behind a caching proxy, or to use
9828 @option{--cache}. Using @option{--cache} has the advantage that it
9829 allows @command{guix publish} to add @code{Content-Length} HTTP header
9832 This option can be repeated, in which case every substitute gets compressed
9833 using all the selected methods, and all of them are advertised. This is
9834 useful when users may not support all the compression methods: they can select
9835 the one they support.
9837 @item --cache=@var{directory}
9838 @itemx -c @var{directory}
9839 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
9840 and only serve archives that are in cache.
9842 When this option is omitted, archives and meta-data are created
9843 on-the-fly. This can reduce the available bandwidth, especially when
9844 compression is enabled, since this may become CPU-bound. Another
9845 drawback of the default mode is that the length of archives is not known
9846 in advance, so @command{guix publish} does not add a
9847 @code{Content-Length} HTTP header to its responses, which in turn
9848 prevents clients from knowing the amount of data being downloaded.
9850 Conversely, when @option{--cache} is used, the first request for a store
9851 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
9852 background process to @dfn{bake} the archive---computing its
9853 @code{.narinfo} and compressing the archive, if needed. Once the
9854 archive is cached in @var{directory}, subsequent requests succeed and
9855 are served directly from the cache, which guarantees that clients get
9856 the best possible bandwidth.
9858 The ``baking'' process is performed by worker threads. By default, one
9859 thread per CPU core is created, but this can be customized. See
9860 @option{--workers} below.
9862 When @option{--ttl} is used, cached entries are automatically deleted
9863 when they have expired.
9865 @item --workers=@var{N}
9866 When @option{--cache} is used, request the allocation of @var{N} worker
9867 threads to ``bake'' archives.
9869 @item --ttl=@var{ttl}
9870 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
9871 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
9872 days, @code{1m} means 1 month, and so on.
9874 This allows the user's Guix to keep substitute information in cache for
9875 @var{ttl}. However, note that @code{guix publish} does not itself
9876 guarantee that the store items it provides will indeed remain available
9877 for as long as @var{ttl}.
9879 Additionally, when @option{--cache} is used, cached entries that have
9880 not been accessed for @var{ttl} and that no longer have a corresponding
9881 item in the store, may be deleted.
9883 @item --nar-path=@var{path}
9884 Use @var{path} as the prefix for the URLs of ``nar'' files
9885 (@pxref{Invoking guix archive, normalized archives}).
9887 By default, nars are served at a URL such as
9888 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
9889 change the @code{/nar} part to @var{path}.
9891 @item --public-key=@var{file}
9892 @itemx --private-key=@var{file}
9893 Use the specific @var{file}s as the public/private key pair used to sign
9894 the store items being published.
9896 The files must correspond to the same key pair (the private key is used
9897 for signing and the public key is merely advertised in the signature
9898 metadata). They must contain keys in the canonical s-expression format
9899 as produced by @command{guix archive --generate-key} (@pxref{Invoking
9900 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
9901 @file{/etc/guix/signing-key.sec} are used.
9903 @item --repl[=@var{port}]
9904 @itemx -r [@var{port}]
9905 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
9906 Reference Manual}) on @var{port} (37146 by default). This is used
9907 primarily for debugging a running @command{guix publish} server.
9910 Enabling @command{guix publish} on Guix System is a one-liner: just
9911 instantiate a @code{guix-publish-service-type} service in the @code{services} field
9912 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
9913 @code{guix-publish-service-type}}).
9915 If you are instead running Guix on a ``foreign distro'', follow these
9920 If your host distro uses the systemd init system:
9923 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
9924 /etc/systemd/system/
9925 # systemctl start guix-publish && systemctl enable guix-publish
9929 If your host distro uses the Upstart init system:
9932 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
9933 # start guix-publish
9937 Otherwise, proceed similarly with your distro's init system.
9940 @node Invoking guix challenge
9941 @section Invoking @command{guix challenge}
9943 @cindex reproducible builds
9944 @cindex verifiable builds
9945 @cindex @command{guix challenge}
9947 Do the binaries provided by this server really correspond to the source
9948 code it claims to build? Is a package build process deterministic?
9949 These are the questions the @command{guix challenge} command attempts to
9952 The former is obviously an important question: Before using a substitute
9953 server (@pxref{Substitutes}), one had better @emph{verify} that it
9954 provides the right binaries, and thus @emph{challenge} it. The latter
9955 is what enables the former: If package builds are deterministic, then
9956 independent builds of the package should yield the exact same result,
9957 bit for bit; if a server provides a binary different from the one
9958 obtained locally, it may be either corrupt or malicious.
9960 We know that the hash that shows up in @file{/gnu/store} file names is
9961 the hash of all the inputs of the process that built the file or
9962 directory---compilers, libraries, build scripts,
9963 etc. (@pxref{Introduction}). Assuming deterministic build processes,
9964 one store file name should map to exactly one build output.
9965 @command{guix challenge} checks whether there is, indeed, a single
9966 mapping by comparing the build outputs of several independent builds of
9967 any given store item.
9969 The command output looks like this:
9972 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
9973 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
9974 updating list of substitutes from 'https://guix.example.org'... 100.0%
9975 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
9976 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9977 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9978 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
9979 /gnu/store/@dots{}-git-2.5.0 contents differ:
9980 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
9981 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
9982 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
9983 /gnu/store/@dots{}-pius-2.1.1 contents differ:
9984 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9985 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9986 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
9990 6,406 store items were analyzed:
9991 - 4,749 (74.1%) were identical
9992 - 525 (8.2%) differed
9993 - 1,132 (17.7%) were inconclusive
9997 In this example, @command{guix challenge} first scans the store to
9998 determine the set of locally-built derivations---as opposed to store
9999 items that were downloaded from a substitute server---and then queries
10000 all the substitute servers. It then reports those store items for which
10001 the servers obtained a result different from the local build.
10003 @cindex non-determinism, in package builds
10004 As an example, @code{guix.example.org} always gets a different answer.
10005 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10006 case of Git. This might indicate that the build process of Git is
10007 non-deterministic, meaning that its output varies as a function of
10008 various things that Guix does not fully control, in spite of building
10009 packages in isolated environments (@pxref{Features}). Most common
10010 sources of non-determinism include the addition of timestamps in build
10011 results, the inclusion of random numbers, and directory listings sorted
10012 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
10015 To find out what is wrong with this Git binary, we can do something along
10016 these lines (@pxref{Invoking guix archive}):
10019 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0 \
10020 | guix archive -x /tmp/git
10021 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
10024 This command shows the difference between the files resulting from the
10025 local build, and the files resulting from the build on
10026 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
10027 diffutils, Comparing and Merging Files}). The @command{diff} command
10028 works great for text files. When binary files differ, a better option
10029 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
10030 visualize differences for all kinds of files.
10032 Once you have done that work, you can tell whether the differences are due
10033 to a non-deterministic build process or to a malicious server. We try
10034 hard to remove sources of non-determinism in packages to make it easier
10035 to verify substitutes, but of course, this is a process that
10036 involves not just Guix, but a large part of the free software community.
10037 In the meantime, @command{guix challenge} is one tool to help address
10040 If you are writing packages for Guix, you are encouraged to check
10041 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
10042 same build result as you did with:
10045 $ guix challenge @var{package}
10049 where @var{package} is a package specification such as
10050 @code{guile@@2.0} or @code{glibc:debug}.
10052 The general syntax is:
10055 guix challenge @var{options} [@var{packages}@dots{}]
10058 When a difference is found between the hash of a locally-built item and
10059 that of a server-provided substitute, or among substitutes provided by
10060 different servers, the command displays it as in the example above and
10061 its exit code is 2 (other non-zero exit codes denote other kinds of
10064 The one option that matters is:
10068 @item --substitute-urls=@var{urls}
10069 Consider @var{urls} the whitespace-separated list of substitute source
10070 URLs to compare to.
10074 Show details about matches (identical contents) in addition to
10075 information about mismatches.
10079 @node Invoking guix copy
10080 @section Invoking @command{guix copy}
10082 @cindex copy, of store items, over SSH
10083 @cindex SSH, copy of store items
10084 @cindex sharing store items across machines
10085 @cindex transferring store items across machines
10086 The @command{guix copy} command copies items from the store of one
10087 machine to that of another machine over a secure shell (SSH)
10088 connection@footnote{This command is available only when Guile-SSH was
10089 found. @xref{Requirements}, for details.}. For example, the following
10090 command copies the @code{coreutils} package, the user's profile, and all
10091 their dependencies over to @var{host}, logged in as @var{user}:
10094 guix copy --to=@var{user}@@@var{host} \
10095 coreutils `readlink -f ~/.guix-profile`
10098 If some of the items to be copied are already present on @var{host},
10099 they are not actually sent.
10101 The command below retrieves @code{libreoffice} and @code{gimp} from
10102 @var{host}, assuming they are available there:
10105 guix copy --from=@var{host} libreoffice gimp
10108 The SSH connection is established using the Guile-SSH client, which is
10109 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10110 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10112 The key used to sign items that are sent must be accepted by the remote
10113 machine. Likewise, the key used by the remote machine to sign items you
10114 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10115 own daemon. @xref{Invoking guix archive}, for more information about
10116 store item authentication.
10118 The general syntax is:
10121 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10124 You must always specify one of the following options:
10127 @item --to=@var{spec}
10128 @itemx --from=@var{spec}
10129 Specify the host to send to or receive from. @var{spec} must be an SSH
10130 spec such as @code{example.org}, @code{charlie@@example.org}, or
10131 @code{charlie@@example.org:2222}.
10134 The @var{items} can be either package names, such as @code{gimp}, or
10135 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10137 When specifying the name of a package to send, it is first built if
10138 needed, unless @option{--dry-run} was specified. Common build options
10139 are supported (@pxref{Common Build Options}).
10142 @node Invoking guix container
10143 @section Invoking @command{guix container}
10145 @cindex @command{guix container}
10147 As of version @value{VERSION}, this tool is experimental. The interface
10148 is subject to radical change in the future.
10151 The purpose of @command{guix container} is to manipulate processes
10152 running within an isolated environment, commonly known as a
10153 ``container'', typically created by the @command{guix environment}
10154 (@pxref{Invoking guix environment}) and @command{guix system container}
10155 (@pxref{Invoking guix system}) commands.
10157 The general syntax is:
10160 guix container @var{action} @var{options}@dots{}
10163 @var{action} specifies the operation to perform with a container, and
10164 @var{options} specifies the context-specific arguments for the action.
10166 The following actions are available:
10170 Execute a command within the context of a running container.
10175 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10178 @var{pid} specifies the process ID of the running container.
10179 @var{program} specifies an executable file name within the root file
10180 system of the container. @var{arguments} are the additional options that
10181 will be passed to @var{program}.
10183 The following command launches an interactive login shell inside a
10184 Guix system container, started by @command{guix system container}, and whose
10185 process ID is 9001:
10188 guix container exec 9001 /run/current-system/profile/bin/bash --login
10191 Note that the @var{pid} cannot be the parent process of a container. It
10192 must be PID 1 of the container or one of its child processes.
10196 @node Invoking guix weather
10197 @section Invoking @command{guix weather}
10199 Occasionally you're grumpy because substitutes are lacking and you end
10200 up building packages by yourself (@pxref{Substitutes}). The
10201 @command{guix weather} command reports on substitute availability on the
10202 specified servers so you can have an idea of whether you'll be grumpy
10203 today. It can sometimes be useful info as a user, but it is primarily
10204 useful to people running @command{guix publish} (@pxref{Invoking guix
10207 @cindex statistics, for substitutes
10208 @cindex availability of substitutes
10209 @cindex substitute availability
10210 @cindex weather, substitute availability
10211 Here's a sample run:
10214 $ guix weather --substitute-urls=https://guix.example.org
10215 computing 5,872 package derivations for x86_64-linux...
10216 looking for 6,128 store items on https://guix.example.org..
10217 updating list of substitutes from 'https://guix.example.org'... 100.0%
10218 https://guix.example.org
10219 43.4% substitutes available (2,658 out of 6,128)
10220 7,032.5 MiB of nars (compressed)
10221 19,824.2 MiB on disk (uncompressed)
10222 0.030 seconds per request (182.9 seconds in total)
10223 33.5 requests per second
10225 9.8% (342 out of 3,470) of the missing items are queued
10227 x86_64-linux: 518 (59.7%)
10228 i686-linux: 221 (25.5%)
10229 aarch64-linux: 128 (14.8%)
10230 build rate: 23.41 builds per hour
10231 x86_64-linux: 11.16 builds per hour
10232 i686-linux: 6.03 builds per hour
10233 aarch64-linux: 6.41 builds per hour
10236 @cindex continuous integration, statistics
10237 As you can see, it reports the fraction of all the packages for which
10238 substitutes are available on the server---regardless of whether
10239 substitutes are enabled, and regardless of whether this server's signing
10240 key is authorized. It also reports the size of the compressed archives
10241 (``nars'') provided by the server, the size the corresponding store
10242 items occupy in the store (assuming deduplication is turned off), and
10243 the server's throughput. The second part gives continuous integration
10244 (CI) statistics, if the server supports it. In addition, using the
10245 @option{--coverage} option, @command{guix weather} can list ``important''
10246 package substitutes missing on the server (see below).
10248 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10249 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10250 challenge}, it ignores signatures on those substitutes, which is
10251 innocuous since the command only gathers statistics and cannot install
10254 The general syntax is:
10257 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10260 When @var{packages} is omitted, @command{guix weather} checks the availability
10261 of substitutes for @emph{all} the packages, or for those specified with
10262 @option{--manifest}; otherwise it only considers the specified packages. It
10263 is also possible to query specific system types with @option{--system}. The
10264 available options are listed below.
10267 @item --substitute-urls=@var{urls}
10268 @var{urls} is the space-separated list of substitute server URLs to
10269 query. When this option is omitted, the default set of substitute
10270 servers is queried.
10272 @item --system=@var{system}
10273 @itemx -s @var{system}
10274 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10275 option can be repeated, in which case @command{guix weather} will query
10276 substitutes for several system types.
10278 @item --manifest=@var{file}
10279 Instead of querying substitutes for all the packages, only ask for those
10280 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10281 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10284 @item --coverage[=@var{count}]
10285 @itemx -c [@var{count}]
10286 Report on substitute coverage for packages: list packages with at least
10287 @var{count} dependents (zero by default) for which substitutes are
10288 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10289 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10290 @var{b} usually lacks substitutes as well. The result looks like this:
10293 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10294 computing 8,983 package derivations for x86_64-linux...
10295 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10296 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10297 @value{SUBSTITUTE-URL}
10298 64.7% substitutes available (6,047 out of 9,343)
10300 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10301 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10302 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10303 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10307 What this example shows is that @code{kcoreaddons} and presumably the 58
10308 packages that depend on it have no substitutes at @code{ci.guix.info};
10309 likewise for @code{qgpgme} and the 46 packages that depend on it.
10311 If you are a Guix developer, or if you are taking care of this build farm,
10312 you'll probably want to have a closer look at these packages: they may simply
10316 @node Invoking guix processes
10317 @section Invoking @command{guix processes}
10319 The @command{guix processes} command can be useful to developers and system
10320 administrators, especially on multi-user machines and on build farms: it lists
10321 the current sessions (connections to the daemon), as well as information about
10322 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10323 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10324 listed.}. Here's an example of the information it returns:
10327 $ sudo guix processes
10330 ClientCommand: guix environment --ad-hoc python
10334 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10338 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10339 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10340 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10341 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10342 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10343 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10344 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10347 In this example we see that @command{guix-daemon} has three clients:
10348 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10349 integration tool; their process identifier (PID) is given by the
10350 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10351 @command{guix-daemon} sub-process of this particular session.
10353 The @code{LockHeld} fields show which store items are currently locked by this
10354 session, which corresponds to store items being built or substituted (the
10355 @code{LockHeld} field is not displayed when @command{guix processes} is not
10356 running as root.) Last, by looking at the @code{ChildProcess} field, we
10357 understand that these three builds are being offloaded (@pxref{Daemon Offload
10360 The output is in Recutils format so we can use the handy @command{recsel}
10361 command to select sessions of interest (@pxref{Selection Expressions,,,
10362 recutils, GNU recutils manual}). As an example, the command shows the command
10363 line and PID of the client that triggered the build of a Perl package:
10366 $ sudo guix processes | \
10367 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10369 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10373 @node System Configuration
10374 @chapter System Configuration
10376 @cindex system configuration
10377 Guix System supports a consistent whole-system configuration
10378 mechanism. By that we mean that all aspects of the global system
10379 configuration---such as the available system services, timezone and
10380 locale settings, user accounts---are declared in a single place. Such
10381 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10383 One of the advantages of putting all the system configuration under the
10384 control of Guix is that it supports transactional system upgrades, and
10385 makes it possible to roll back to a previous system instantiation,
10386 should something go wrong with the new one (@pxref{Features}). Another
10387 advantage is that it makes it easy to replicate the exact same configuration
10388 across different machines, or at different points in time, without
10389 having to resort to additional administration tools layered on top of
10390 the own tools of the system.
10391 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10393 This section describes this mechanism. First we focus on the system
10394 administrator's viewpoint---explaining how the system is configured and
10395 instantiated. Then we show how this mechanism can be extended, for
10396 instance to support new system services.
10399 * Using the Configuration System:: Customizing your GNU system.
10400 * operating-system Reference:: Detail of operating-system declarations.
10401 * File Systems:: Configuring file system mounts.
10402 * Mapped Devices:: Block device extra processing.
10403 * User Accounts:: Specifying user accounts.
10404 * Keyboard Layout:: How the system interprets key strokes.
10405 * Locales:: Language and cultural convention settings.
10406 * Services:: Specifying system services.
10407 * Setuid Programs:: Programs running with root privileges.
10408 * X.509 Certificates:: Authenticating HTTPS servers.
10409 * Name Service Switch:: Configuring libc's name service switch.
10410 * Initial RAM Disk:: Linux-Libre bootstrapping.
10411 * Bootloader Configuration:: Configuring the boot loader.
10412 * Invoking guix system:: Instantiating a system configuration.
10413 * Invoking guix deploy:: Deploying a system configuration to a remote host.
10414 * Running Guix in a VM:: How to run Guix System in a virtual machine.
10415 * Defining Services:: Adding new service definitions.
10418 @node Using the Configuration System
10419 @section Using the Configuration System
10421 The operating system is configured by providing an
10422 @code{operating-system} declaration in a file that can then be passed to
10423 the @command{guix system} command (@pxref{Invoking guix system}). A
10424 simple setup, with the default system services, the default Linux-Libre
10425 kernel, initial RAM disk, and boot loader looks like this:
10427 @findex operating-system
10429 @include os-config-bare-bones.texi
10432 This example should be self-describing. Some of the fields defined
10433 above, such as @code{host-name} and @code{bootloader}, are mandatory.
10434 Others, such as @code{packages} and @code{services}, can be omitted, in
10435 which case they get a default value.
10437 Below we discuss the effect of some of the most important fields
10438 (@pxref{operating-system Reference}, for details about all the available
10439 fields), and how to @dfn{instantiate} the operating system using
10440 @command{guix system}.
10442 @unnumberedsubsec Bootloader
10444 @cindex legacy boot, on Intel machines
10445 @cindex BIOS boot, on Intel machines
10448 The @code{bootloader} field describes the method that will be used to boot
10449 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
10450 mode, as in the example above. However, more recent machines rely instead on
10451 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
10452 the @code{bootloader} field should contain something along these lines:
10455 (bootloader-configuration
10456 (bootloader grub-efi-bootloader)
10457 (target "/boot/efi"))
10460 @xref{Bootloader Configuration}, for more information on the available
10461 configuration options.
10463 @unnumberedsubsec Globally-Visible Packages
10465 @vindex %base-packages
10466 The @code{packages} field lists packages that will be globally visible
10467 on the system, for all user accounts---i.e., in every user's @code{PATH}
10468 environment variable---in addition to the per-user profiles
10469 (@pxref{Invoking guix package}). The @code{%base-packages} variable
10470 provides all the tools one would expect for basic user and administrator
10471 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
10472 the GNU Zile lightweight text editor, @command{find}, @command{grep},
10473 etc. The example above adds GNU@tie{}Screen to those,
10474 taken from the @code{(gnu packages screen)}
10475 module (@pxref{Package Modules}). The
10476 @code{(list package output)} syntax can be used to add a specific output
10480 (use-modules (gnu packages))
10481 (use-modules (gnu packages dns))
10485 (packages (cons (list bind "utils")
10489 @findex specification->package
10490 Referring to packages by variable name, like @code{bind} above, has
10491 the advantage of being unambiguous; it also allows typos and such to be
10492 diagnosed right away as ``unbound variables''. The downside is that one
10493 needs to know which module defines which package, and to augment the
10494 @code{use-package-modules} line accordingly. To avoid that, one can use
10495 the @code{specification->package} procedure of the @code{(gnu packages)}
10496 module, which returns the best package for a given name or name and
10500 (use-modules (gnu packages))
10504 (packages (append (map specification->package
10505 '("tcpdump" "htop" "gnupg@@2.0"))
10509 @unnumberedsubsec System Services
10512 @vindex %base-services
10513 The @code{services} field lists @dfn{system services} to be made
10514 available when the system starts (@pxref{Services}).
10515 The @code{operating-system} declaration above specifies that, in
10516 addition to the basic services, we want the OpenSSH secure shell
10517 daemon listening on port 2222 (@pxref{Networking Services,
10518 @code{openssh-service-type}}). Under the hood,
10519 @code{openssh-service-type} arranges so that @command{sshd} is started with the
10520 right command-line options, possibly with supporting configuration files
10521 generated as needed (@pxref{Defining Services}).
10523 @cindex customization, of services
10524 @findex modify-services
10525 Occasionally, instead of using the base services as is, you will want to
10526 customize them. To do this, use @code{modify-services} (@pxref{Service
10527 Reference, @code{modify-services}}) to modify the list.
10529 For example, suppose you want to modify @code{guix-daemon} and Mingetty
10530 (the console log-in) in the @code{%base-services} list (@pxref{Base
10531 Services, @code{%base-services}}). To do that, you can write the
10532 following in your operating system declaration:
10535 (define %my-services
10536 ;; My very own list of services.
10537 (modify-services %base-services
10538 (guix-service-type config =>
10539 (guix-configuration
10541 (use-substitutes? #f)
10542 (extra-options '("--gc-keep-derivations"))))
10543 (mingetty-service-type config =>
10544 (mingetty-configuration
10545 (inherit config)))))
10549 (services %my-services))
10552 This changes the configuration---i.e., the service parameters---of the
10553 @code{guix-service-type} instance, and that of all the
10554 @code{mingetty-service-type} instances in the @code{%base-services} list.
10555 Observe how this is accomplished: first, we arrange for the original
10556 configuration to be bound to the identifier @code{config} in the
10557 @var{body}, and then we write the @var{body} so that it evaluates to the
10558 desired configuration. In particular, notice how we use @code{inherit}
10559 to create a new configuration which has the same values as the old
10560 configuration, but with a few modifications.
10562 @cindex encrypted disk
10563 The configuration for a typical ``desktop'' usage, with an encrypted
10564 root partition, the X11 display
10565 server, GNOME and Xfce (users can choose which of these desktop
10566 environments to use at the log-in screen by pressing @kbd{F1}), network
10567 management, power management, and more, would look like this:
10570 @include os-config-desktop.texi
10573 A graphical system with a choice of lightweight window managers
10574 instead of full-blown desktop environments would look like this:
10577 @include os-config-lightweight-desktop.texi
10580 This example refers to the @file{/boot/efi} file system by its UUID,
10581 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
10582 as returned by the @command{blkid} command.
10584 @xref{Desktop Services}, for the exact list of services provided by
10585 @code{%desktop-services}. @xref{X.509 Certificates}, for background
10586 information about the @code{nss-certs} package that is used here.
10588 Again, @code{%desktop-services} is just a list of service objects. If
10589 you want to remove services from there, you can do so using the
10590 procedures for list filtering (@pxref{SRFI-1 Filtering and
10591 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
10592 following expression returns a list that contains all the services in
10593 @code{%desktop-services} minus the Avahi service:
10596 (remove (lambda (service)
10597 (eq? (service-kind service) avahi-service-type))
10601 @unnumberedsubsec Instantiating the System
10603 Assuming the @code{operating-system} declaration
10604 is stored in the @file{my-system-config.scm}
10605 file, the @command{guix system reconfigure my-system-config.scm} command
10606 instantiates that configuration, and makes it the default GRUB boot
10607 entry (@pxref{Invoking guix system}).
10609 The normal way to change the system configuration is by updating this
10610 file and re-running @command{guix system reconfigure}. One should never
10611 have to touch files in @file{/etc} or to run commands that modify the
10612 system state such as @command{useradd} or @command{grub-install}. In
10613 fact, you must avoid that since that would not only void your warranty
10614 but also prevent you from rolling back to previous versions of your
10615 system, should you ever need to.
10617 @cindex roll-back, of the operating system
10618 Speaking of roll-back, each time you run @command{guix system
10619 reconfigure}, a new @dfn{generation} of the system is created---without
10620 modifying or deleting previous generations. Old system generations get
10621 an entry in the bootloader boot menu, allowing you to boot them in case
10622 something went wrong with the latest generation. Reassuring, no? The
10623 @command{guix system list-generations} command lists the system
10624 generations available on disk. It is also possible to roll back the
10625 system via the commands @command{guix system roll-back} and
10626 @command{guix system switch-generation}.
10628 Although the @command{guix system reconfigure} command will not modify
10629 previous generations, you must take care when the current generation is not
10630 the latest (e.g., after invoking @command{guix system roll-back}), since
10631 the operation might overwrite a later generation (@pxref{Invoking guix
10634 @unnumberedsubsec The Programming Interface
10636 At the Scheme level, the bulk of an @code{operating-system} declaration
10637 is instantiated with the following monadic procedure (@pxref{The Store
10640 @deffn {Monadic Procedure} operating-system-derivation os
10641 Return a derivation that builds @var{os}, an @code{operating-system}
10642 object (@pxref{Derivations}).
10644 The output of the derivation is a single directory that refers to all
10645 the packages, configuration files, and other supporting files needed to
10646 instantiate @var{os}.
10649 This procedure is provided by the @code{(gnu system)} module. Along
10650 with @code{(gnu services)} (@pxref{Services}), this module contains the
10651 guts of Guix System. Make sure to visit it!
10654 @node operating-system Reference
10655 @section @code{operating-system} Reference
10657 This section summarizes all the options available in
10658 @code{operating-system} declarations (@pxref{Using the Configuration
10661 @deftp {Data Type} operating-system
10662 This is the data type representing an operating system configuration.
10663 By that, we mean all the global system configuration, not per-user
10664 configuration (@pxref{Using the Configuration System}).
10667 @item @code{kernel} (default: @var{linux-libre})
10668 The package object of the operating system kernel to use@footnote{Currently
10669 only the Linux-libre kernel is supported. In the future, it will be
10670 possible to use the GNU@tie{}Hurd.}.
10672 @item @code{kernel-arguments} (default: @code{'("quiet")})
10673 List of strings or gexps representing additional arguments to pass on
10674 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
10676 @item @code{bootloader}
10677 The system bootloader configuration object. @xref{Bootloader Configuration}.
10680 This is the label (a string) as it appears in the bootloader's menu entry.
10681 The default label includes the kernel name and version.
10683 @item @code{keyboard-layout} (default: @code{#f})
10684 This field specifies the keyboard layout to use in the console. It can be
10685 either @code{#f}, in which case the default keyboard layout is used (usually
10686 US English), or a @code{<keyboard-layout>} record.
10688 This keyboard layout is in effect as soon as the kernel has booted. For
10689 instance, it is the keyboard layout in effect when you type a passphrase if
10690 your root file system is on a @code{luks-device-mapping} mapped device
10691 (@pxref{Mapped Devices}).
10694 This does @emph{not} specify the keyboard layout used by the bootloader, nor
10695 that used by the graphical display server. @xref{Bootloader Configuration},
10696 for information on how to specify the bootloader's keyboard layout. @xref{X
10697 Window}, for information on how to specify the keyboard layout used by the X
10701 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
10703 @cindex initial RAM disk
10704 The list of Linux kernel modules that need to be available in the
10705 initial RAM disk. @xref{Initial RAM Disk}.
10707 @item @code{initrd} (default: @code{base-initrd})
10708 A procedure that returns an initial RAM disk for the Linux
10709 kernel. This field is provided to support low-level customization and
10710 should rarely be needed for casual use. @xref{Initial RAM Disk}.
10712 @item @code{firmware} (default: @code{%base-firmware})
10714 List of firmware packages loadable by the operating system kernel.
10716 The default includes firmware needed for Atheros- and Broadcom-based
10717 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
10718 respectively). @xref{Hardware Considerations}, for more info on
10719 supported hardware.
10721 @item @code{host-name}
10724 @item @code{hosts-file}
10726 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
10727 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
10728 Reference Manual}). The default is a file with entries for
10729 @code{localhost} and @var{host-name}.
10731 @item @code{mapped-devices} (default: @code{'()})
10732 A list of mapped devices. @xref{Mapped Devices}.
10734 @item @code{file-systems}
10735 A list of file systems. @xref{File Systems}.
10737 @item @code{swap-devices} (default: @code{'()})
10738 @cindex swap devices
10739 A list of strings identifying devices or files to be used for ``swap
10740 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
10741 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
10742 It is possible to specify a swap file in a file system on a mapped
10743 device, provided that the necessary device mapping and file system are
10744 also specified. @xref{Mapped Devices} and @ref{File Systems}.
10746 @item @code{users} (default: @code{%base-user-accounts})
10747 @itemx @code{groups} (default: @code{%base-groups})
10748 List of user accounts and groups. @xref{User Accounts}.
10750 If the @code{users} list lacks a user account with UID@tie{}0, a
10751 ``root'' account with UID@tie{}0 is automatically added.
10753 @item @code{skeletons} (default: @code{(default-skeletons)})
10754 A list target file name/file-like object tuples (@pxref{G-Expressions,
10755 file-like objects}). These are the skeleton files that will be added to
10756 the home directory of newly-created user accounts.
10758 For instance, a valid value may look like this:
10761 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
10762 (".guile" ,(plain-file "guile"
10763 "(use-modules (ice-9 readline))
10764 (activate-readline)")))
10767 @item @code{issue} (default: @code{%default-issue})
10768 A string denoting the contents of the @file{/etc/issue} file, which is
10769 displayed when users log in on a text console.
10771 @item @code{packages} (default: @code{%base-packages})
10772 The set of packages installed in the global profile, which is accessible
10773 at @file{/run/current-system/profile}.
10775 The default set includes core utilities and it is good practice to
10776 install non-core utilities in user profiles (@pxref{Invoking guix
10779 @item @code{timezone}
10780 A timezone identifying string---e.g., @code{"Europe/Paris"}.
10782 You can run the @command{tzselect} command to find out which timezone
10783 string corresponds to your region. Choosing an invalid timezone name
10784 causes @command{guix system} to fail.
10786 @item @code{locale} (default: @code{"en_US.utf8"})
10787 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
10788 Library Reference Manual}). @xref{Locales}, for more information.
10790 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
10791 The list of locale definitions to be compiled and that may be used at
10792 run time. @xref{Locales}.
10794 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
10795 The list of GNU@tie{}libc packages whose locale data and tools are used
10796 to build the locale definitions. @xref{Locales}, for compatibility
10797 considerations that justify this option.
10799 @item @code{name-service-switch} (default: @code{%default-nss})
10800 Configuration of the libc name service switch (NSS)---a
10801 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
10804 @item @code{services} (default: @code{%base-services})
10805 A list of service objects denoting system services. @xref{Services}.
10807 @cindex essential services
10808 @item @code{essential-services} (default: ...)
10809 The list of ``essential services''---i.e., things like instances of
10810 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
10811 Reference}), which are derived from the operating system definition itself.
10812 As a user you should @emph{never} need to touch this field.
10814 @item @code{pam-services} (default: @code{(base-pam-services)})
10816 @cindex pluggable authentication modules
10817 Linux @dfn{pluggable authentication module} (PAM) services.
10818 @c FIXME: Add xref to PAM services section.
10820 @item @code{setuid-programs} (default: @var{%setuid-programs})
10821 List of string-valued G-expressions denoting setuid programs.
10822 @xref{Setuid Programs}.
10824 @item @code{sudoers-file} (default: @var{%sudoers-specification})
10825 @cindex sudoers file
10826 The contents of the @file{/etc/sudoers} file as a file-like object
10827 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
10829 This file specifies which users can use the @command{sudo} command, what
10830 they are allowed to do, and what privileges they may gain. The default
10831 is that only @code{root} and members of the @code{wheel} group may use
10836 @deffn {Scheme Syntax} this-operating-system
10837 When used in the @emph{lexical scope} of an operating system field definition,
10838 this identifier resolves to the operating system being defined.
10840 The example below shows how to refer to the operating system being defined in
10841 the definition of the @code{label} field:
10844 (use-modules (gnu) (guix))
10848 (label (package-full-name
10849 (operating-system-kernel this-operating-system))))
10852 It is an error to refer to @code{this-operating-system} outside an operating
10859 @section File Systems
10861 The list of file systems to be mounted is specified in the
10862 @code{file-systems} field of the operating system declaration
10863 (@pxref{Using the Configuration System}). Each file system is declared
10864 using the @code{file-system} form, like this:
10868 (mount-point "/home")
10869 (device "/dev/sda3")
10873 As usual, some of the fields are mandatory---those shown in the example
10874 above---while others can be omitted. These are described below.
10876 @deftp {Data Type} file-system
10877 Objects of this type represent file systems to be mounted. They
10878 contain the following members:
10882 This is a string specifying the type of the file system---e.g.,
10885 @item @code{mount-point}
10886 This designates the place where the file system is to be mounted.
10888 @item @code{device}
10889 This names the ``source'' of the file system. It can be one of three
10890 things: a file system label, a file system UUID, or the name of a
10891 @file{/dev} node. Labels and UUIDs offer a way to refer to file
10892 systems without having to hard-code their actual device
10893 name@footnote{Note that, while it is tempting to use
10894 @file{/dev/disk/by-uuid} and similar device names to achieve the same
10895 result, this is not recommended: These special device nodes are created
10896 by the udev daemon and may be unavailable at the time the device is
10899 @findex file-system-label
10900 File system labels are created using the @code{file-system-label}
10901 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
10902 plain strings. Here's an example of a file system referred to by its
10903 label, as shown by the @command{e2label} command:
10907 (mount-point "/home")
10909 (device (file-system-label "my-home")))
10913 UUIDs are converted from their string representation (as shown by the
10914 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
10915 @code{uuid} form expects 16-byte UUIDs as defined in
10916 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
10917 form of UUID used by the ext2 family of file systems and others, but it
10918 is different from ``UUIDs'' found in FAT file systems, for instance.},
10923 (mount-point "/home")
10925 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
10928 When the source of a file system is a mapped device (@pxref{Mapped
10929 Devices}), its @code{device} field @emph{must} refer to the mapped
10930 device name---e.g., @file{"/dev/mapper/root-partition"}.
10931 This is required so that
10932 the system knows that mounting the file system depends on having the
10933 corresponding device mapping established.
10935 @item @code{flags} (default: @code{'()})
10936 This is a list of symbols denoting mount flags. Recognized flags
10937 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
10938 access to special files), @code{no-suid} (ignore setuid and setgid
10939 bits), @code{no-atime} (do not update file access times), and @code{no-exec}
10940 (disallow program execution). @xref{Mount-Unmount-Remount,,, libc, The GNU C
10941 Library Reference Manual}, for more information on these flags.
10943 @item @code{options} (default: @code{#f})
10944 This is either @code{#f}, or a string denoting mount options passed to the
10945 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
10946 Reference Manual}, for details and run @command{man 8 mount} for options for
10947 various file systems.
10949 @item @code{mount?} (default: @code{#t})
10950 This value indicates whether to automatically mount the file system when
10951 the system is brought up. When set to @code{#f}, the file system gets
10952 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
10953 is not automatically mounted.
10955 @item @code{needed-for-boot?} (default: @code{#f})
10956 This Boolean value indicates whether the file system is needed when
10957 booting. If that is true, then the file system is mounted when the
10958 initial RAM disk (initrd) is loaded. This is always the case, for
10959 instance, for the root file system.
10961 @item @code{check?} (default: @code{#t})
10962 This Boolean indicates whether the file system needs to be checked for
10963 errors before being mounted.
10965 @item @code{create-mount-point?} (default: @code{#f})
10966 When true, the mount point is created if it does not exist yet.
10968 @item @code{dependencies} (default: @code{'()})
10969 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
10970 representing file systems that must be mounted or mapped devices that
10971 must be opened before (and unmounted or closed after) this one.
10973 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
10974 a dependency of @file{/sys/fs/cgroup/cpu} and
10975 @file{/sys/fs/cgroup/memory}.
10977 Another example is a file system that depends on a mapped device, for
10978 example for an encrypted partition (@pxref{Mapped Devices}).
10982 The @code{(gnu system file-systems)} exports the following useful
10985 @defvr {Scheme Variable} %base-file-systems
10986 These are essential file systems that are required on normal systems,
10987 such as @var{%pseudo-terminal-file-system} and @var{%immutable-store} (see
10988 below.) Operating system declarations should always contain at least
10992 @defvr {Scheme Variable} %pseudo-terminal-file-system
10993 This is the file system to be mounted as @file{/dev/pts}. It supports
10994 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
10995 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
10996 Manual}). Pseudo-terminals are used by terminal emulators such as
11000 @defvr {Scheme Variable} %shared-memory-file-system
11001 This file system is mounted as @file{/dev/shm} and is used to support
11002 memory sharing across processes (@pxref{Memory-mapped I/O,
11003 @code{shm_open},, libc, The GNU C Library Reference Manual}).
11006 @defvr {Scheme Variable} %immutable-store
11007 This file system performs a read-only ``bind mount'' of
11008 @file{/gnu/store}, making it read-only for all the users including
11009 @code{root}. This prevents against accidental modification by software
11010 running as @code{root} or by system administrators.
11012 The daemon itself is still able to write to the store: it remounts it
11013 read-write in its own ``name space.''
11016 @defvr {Scheme Variable} %binary-format-file-system
11017 The @code{binfmt_misc} file system, which allows handling of arbitrary
11018 executable file types to be delegated to user space. This requires the
11019 @code{binfmt.ko} kernel module to be loaded.
11022 @defvr {Scheme Variable} %fuse-control-file-system
11023 The @code{fusectl} file system, which allows unprivileged users to mount
11024 and unmount user-space FUSE file systems. This requires the
11025 @code{fuse.ko} kernel module to be loaded.
11028 @node Mapped Devices
11029 @section Mapped Devices
11031 @cindex device mapping
11032 @cindex mapped devices
11033 The Linux kernel has a notion of @dfn{device mapping}: a block device,
11034 such as a hard disk partition, can be @dfn{mapped} into another device,
11035 usually in @code{/dev/mapper/},
11036 with additional processing over the data that flows through
11037 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
11038 concept of a ``mapped device'' and that of a file system: both boil down
11039 to @emph{translating} input/output operations made on a file to
11040 operations on its backing store. Thus, the Hurd implements mapped
11041 devices, like file systems, using the generic @dfn{translator} mechanism
11042 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
11043 typical example is encryption device mapping: all writes to the mapped
11044 device are encrypted, and all reads are deciphered, transparently.
11045 Guix extends this notion by considering any device or set of devices that
11046 are @dfn{transformed} in some way to create a new device; for instance,
11047 RAID devices are obtained by @dfn{assembling} several other devices, such
11048 as hard disks or partitions, into a new one that behaves as one partition.
11049 Other examples, not yet implemented, are LVM logical volumes.
11051 Mapped devices are declared using the @code{mapped-device} form,
11052 defined as follows; for examples, see below.
11054 @deftp {Data Type} mapped-device
11055 Objects of this type represent device mappings that will be made when
11056 the system boots up.
11060 This is either a string specifying the name of the block device to be mapped,
11061 such as @code{"/dev/sda3"}, or a list of such strings when several devices
11062 need to be assembled for creating a new one.
11065 This string specifies the name of the resulting mapped device. For
11066 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
11067 specifying @code{"my-partition"} leads to the creation of
11068 the @code{"/dev/mapper/my-partition"} device.
11069 For RAID devices of type @code{raid-device-mapping}, the full device name
11070 such as @code{"/dev/md0"} needs to be given.
11073 This must be a @code{mapped-device-kind} object, which specifies how
11074 @var{source} is mapped to @var{target}.
11078 @defvr {Scheme Variable} luks-device-mapping
11079 This defines LUKS block device encryption using the @command{cryptsetup}
11080 command from the package with the same name. It relies on the
11081 @code{dm-crypt} Linux kernel module.
11084 @defvr {Scheme Variable} raid-device-mapping
11085 This defines a RAID device, which is assembled using the @code{mdadm}
11086 command from the package with the same name. It requires a Linux kernel
11087 module for the appropriate RAID level to be loaded, such as @code{raid456}
11088 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
11091 @cindex disk encryption
11093 The following example specifies a mapping from @file{/dev/sda3} to
11094 @file{/dev/mapper/home} using LUKS---the
11095 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
11096 standard mechanism for disk encryption.
11097 The @file{/dev/mapper/home}
11098 device can then be used as the @code{device} of a @code{file-system}
11099 declaration (@pxref{File Systems}).
11103 (source "/dev/sda3")
11105 (type luks-device-mapping))
11108 Alternatively, to become independent of device numbering, one may obtain
11109 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11113 cryptsetup luksUUID /dev/sda3
11116 and use it as follows:
11120 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11122 (type luks-device-mapping))
11125 @cindex swap encryption
11126 It is also desirable to encrypt swap space, since swap space may contain
11127 sensitive data. One way to accomplish that is to use a swap file in a
11128 file system on a device mapped via LUKS encryption. In this way, the
11129 swap file is encrypted because the entire device is encrypted.
11130 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11132 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11133 may be declared as follows:
11137 (source (list "/dev/sda1" "/dev/sdb1"))
11138 (target "/dev/md0")
11139 (type raid-device-mapping))
11142 The @file{/dev/md0} device can then be used as the @code{device} of a
11143 @code{file-system} declaration (@pxref{File Systems}).
11144 Note that the RAID level need not be given; it is chosen during the
11145 initial creation and formatting of the RAID device and is determined
11146 automatically later.
11149 @node User Accounts
11150 @section User Accounts
11154 @cindex user accounts
11155 User accounts and groups are entirely managed through the
11156 @code{operating-system} declaration. They are specified with the
11157 @code{user-account} and @code{user-group} forms:
11163 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11164 "audio" ;sound card
11165 "video" ;video devices such as webcams
11166 "cdrom")) ;the good ol' CD-ROM
11167 (comment "Bob's sister")
11168 (home-directory "/home/alice"))
11171 When booting or upon completion of @command{guix system reconfigure},
11172 the system ensures that only the user accounts and groups specified in
11173 the @code{operating-system} declaration exist, and with the specified
11174 properties. Thus, account or group creations or modifications made by
11175 directly invoking commands such as @command{useradd} are lost upon
11176 reconfiguration or reboot. This ensures that the system remains exactly
11179 @deftp {Data Type} user-account
11180 Objects of this type represent user accounts. The following members may
11185 The name of the user account.
11189 This is the name (a string) or identifier (a number) of the user group
11190 this account belongs to.
11192 @item @code{supplementary-groups} (default: @code{'()})
11193 Optionally, this can be defined as a list of group names that this
11194 account belongs to.
11196 @item @code{uid} (default: @code{#f})
11197 This is the user ID for this account (a number), or @code{#f}. In the
11198 latter case, a number is automatically chosen by the system when the
11199 account is created.
11201 @item @code{comment} (default: @code{""})
11202 A comment about the account, such as the account owner's full name.
11204 @item @code{home-directory}
11205 This is the name of the home directory for the account.
11207 @item @code{create-home-directory?} (default: @code{#t})
11208 Indicates whether the home directory of this account should be created
11209 if it does not exist yet.
11211 @item @code{shell} (default: Bash)
11212 This is a G-expression denoting the file name of a program to be used as
11213 the shell (@pxref{G-Expressions}).
11215 @item @code{system?} (default: @code{#f})
11216 This Boolean value indicates whether the account is a ``system''
11217 account. System accounts are sometimes treated specially; for instance,
11218 graphical login managers do not list them.
11220 @anchor{user-account-password}
11221 @cindex password, for user accounts
11222 @item @code{password} (default: @code{#f})
11223 You would normally leave this field to @code{#f}, initialize user
11224 passwords as @code{root} with the @command{passwd} command, and then let
11225 users change it with @command{passwd}. Passwords set with
11226 @command{passwd} are of course preserved across reboot and
11229 If you @emph{do} want to set an initial password for an account, then
11230 this field must contain the encrypted password, as a string. You can use the
11231 @code{crypt} procedure for this purpose:
11238 ;; Specify a SHA-512-hashed initial password.
11239 (password (crypt "InitialPassword!" "$6$abc")))
11243 The hash of this initial password will be available in a file in
11244 @file{/gnu/store}, readable by all the users, so this method must be used with
11248 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11249 more information on password encryption, and @ref{Encryption,,, guile, GNU
11250 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11256 User group declarations are even simpler:
11259 (user-group (name "students"))
11262 @deftp {Data Type} user-group
11263 This type is for, well, user groups. There are just a few fields:
11267 The name of the group.
11269 @item @code{id} (default: @code{#f})
11270 The group identifier (a number). If @code{#f}, a new number is
11271 automatically allocated when the group is created.
11273 @item @code{system?} (default: @code{#f})
11274 This Boolean value indicates whether the group is a ``system'' group.
11275 System groups have low numerical IDs.
11277 @item @code{password} (default: @code{#f})
11278 What, user groups can have a password? Well, apparently yes. Unless
11279 @code{#f}, this field specifies the password of the group.
11284 For convenience, a variable lists all the basic user groups one may
11287 @defvr {Scheme Variable} %base-groups
11288 This is the list of basic user groups that users and/or packages expect
11289 to be present on the system. This includes groups such as ``root'',
11290 ``wheel'', and ``users'', as well as groups used to control access to
11291 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11294 @defvr {Scheme Variable} %base-user-accounts
11295 This is the list of basic system accounts that programs may expect to
11296 find on a GNU/Linux system, such as the ``nobody'' account.
11298 Note that the ``root'' account is not included here. It is a
11299 special-case and is automatically added whether or not it is specified.
11302 @node Keyboard Layout
11303 @section Keyboard Layout
11305 @cindex keyboard layout
11307 To specify what each key of your keyboard does, you need to tell the operating
11308 system what @dfn{keyboard layout} you want to use. The default, when nothing
11309 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11310 However, German speakers will usually prefer the German QWERTZ layout, French
11311 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11312 or bépo, and they might even want to further customize the effect of some of
11313 the keys. This section explains how to get that done.
11315 @cindex keyboard layout, definition
11316 There are three components that will want to know about your keyboard layout:
11320 The @emph{bootloader} may want to know what keyboard layout you want to use
11321 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11322 you want, for instance, to make sure that you can type the passphrase of your
11323 encrypted root partition using the right layout.
11326 The @emph{operating system kernel}, Linux, will need that so that the console
11327 is properly configured (@pxref{operating-system Reference,
11328 @code{keyboard-layout}}).
11331 The @emph{graphical display server}, usually Xorg, also has its own idea of
11332 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11335 Guix allows you to configure all three separately but, fortunately, it allows
11336 you to share the same keyboard layout for all three components.
11338 @cindex XKB, keyboard layouts
11339 Keyboard layouts are represented by records created by the
11340 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11341 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11342 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11343 optional variant name, an optional keyboard model name, and a possibly empty
11344 list of additional options. In most cases the layout name is all you care
11345 about. Here are a few example:
11348 ;; The German QWERTZ layout. Here we assume a standard
11349 ;; "pc105" keyboard model.
11350 (keyboard-layout "de")
11352 ;; The bépo variant of the French layout.
11353 (keyboard-layout "fr" "bepo")
11355 ;; The Catalan layout.
11356 (keyboard-layout "es" "cat")
11358 ;; The Latin American Spanish layout. In addition, the
11359 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11360 ;; and the "Menu" key is used as a "Compose" key to enter
11361 ;; accented letters.
11362 (keyboard-layout "latam"
11363 #:options '("ctrl:nocaps" "compose:menu"))
11365 ;; The Russian layout for a ThinkPad keyboard.
11366 (keyboard-layout "ru" #:model "thinkpad")
11368 ;; The "US international" layout, which is the US layout plus
11369 ;; dead keys to enter accented characters. This is for an
11370 ;; Apple MacBook keyboard.
11371 (keyboard-layout "us" "intl" #:model "macbook78")
11374 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11375 for a complete list of supported layouts, variants, and models.
11377 @cindex keyboard layout, configuration
11378 Let's say you want your system to use the Turkish keyboard layout throughout
11379 your system---bootloader, console, and Xorg. Here's what your system
11380 configuration would look like:
11382 @findex set-xorg-configuration
11384 ;; Using the Turkish layout for the bootloader, the console,
11389 (keyboard-layout (keyboard-layout "tr")) ;for the console
11390 (bootloader (bootloader-configuration
11391 (bootloader grub-efi-bootloader)
11392 (target "/boot/efi")
11393 (keyboard-layout keyboard-layout))) ;for GRUB
11394 (services (cons (set-xorg-configuration
11395 (xorg-configuration ;for Xorg
11396 (keyboard-layout keyboard-layout)))
11397 %desktop-services)))
11400 In the example above, for GRUB and for Xorg, we just refer to the
11401 @code{keyboard-layout} field defined above, but we could just as well refer to
11402 a different layout. The @code{set-xorg-configuration} procedure communicates
11403 the desired Xorg configuration to the graphical log-in manager, by default
11406 We've discussed how to specify the @emph{default} keyboard layout of your
11407 system when it starts, but you can also adjust it at run time:
11411 If you're using GNOME, its settings panel has a ``Region & Language'' entry
11412 where you can select one or more keyboard layouts.
11415 Under Xorg, the @command{setxkbmap} command (from the same-named package)
11416 allows you to change the current layout. For example, this is how you would
11417 change the layout to US Dvorak:
11420 setxkbmap us dvorak
11424 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
11425 console. However, note that @code{loadkeys} does @emph{not} use the XKB
11426 keyboard layout categorization described above. The command below loads the
11427 French bépo layout:
11438 A @dfn{locale} defines cultural conventions for a particular language
11439 and region of the world (@pxref{Locales,,, libc, The GNU C Library
11440 Reference Manual}). Each locale has a name that typically has the form
11441 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
11442 @code{fr_LU.utf8} designates the locale for the French language, with
11443 cultural conventions from Luxembourg, and using the UTF-8 encoding.
11445 @cindex locale definition
11446 Usually, you will want to specify the default locale for the machine
11447 using the @code{locale} field of the @code{operating-system} declaration
11448 (@pxref{operating-system Reference, @code{locale}}).
11450 The selected locale is automatically added to the @dfn{locale
11451 definitions} known to the system if needed, with its codeset inferred
11452 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
11453 @code{UTF-8} codeset. Additional locale definitions can be specified in
11454 the @code{locale-definitions} slot of @code{operating-system}---this is
11455 useful, for instance, if the codeset could not be inferred from the
11456 locale name. The default set of locale definitions includes some widely
11457 used locales, but not all the available locales, in order to save space.
11459 For instance, to add the North Frisian locale for Germany, the value of
11463 (cons (locale-definition
11464 (name "fy_DE.utf8") (source "fy_DE"))
11465 %default-locale-definitions)
11468 Likewise, to save space, one might want @code{locale-definitions} to
11469 list only the locales that are actually used, as in:
11472 (list (locale-definition
11473 (name "ja_JP.eucjp") (source "ja_JP")
11474 (charset "EUC-JP")))
11478 The compiled locale definitions are available at
11479 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
11480 version, which is the default location where the GNU@tie{}libc provided
11481 by Guix looks for locale data. This can be overridden using the
11482 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
11483 @code{LOCPATH} and locale packages}).
11485 The @code{locale-definition} form is provided by the @code{(gnu system
11486 locale)} module. Details are given below.
11488 @deftp {Data Type} locale-definition
11489 This is the data type of a locale definition.
11494 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
11495 Reference Manual}, for more information on locale names.
11497 @item @code{source}
11498 The name of the source for that locale. This is typically the
11499 @code{@var{language}_@var{territory}} part of the locale name.
11501 @item @code{charset} (default: @code{"UTF-8"})
11502 The ``character set'' or ``code set'' for that locale,
11503 @uref{https://www.iana.org/assignments/character-sets, as defined by
11509 @defvr {Scheme Variable} %default-locale-definitions
11510 A list of commonly used UTF-8 locales, used as the default
11511 value of the @code{locale-definitions} field of @code{operating-system}
11514 @cindex locale name
11515 @cindex normalized codeset in locale names
11516 These locale definitions use the @dfn{normalized codeset} for the part
11517 that follows the dot in the name (@pxref{Using gettextized software,
11518 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
11519 instance it has @code{uk_UA.utf8} but @emph{not}, say,
11520 @code{uk_UA.UTF-8}.
11523 @subsection Locale Data Compatibility Considerations
11525 @cindex incompatibility, of locale data
11526 @code{operating-system} declarations provide a @code{locale-libcs} field
11527 to specify the GNU@tie{}libc packages that are used to compile locale
11528 declarations (@pxref{operating-system Reference}). ``Why would I
11529 care?'', you may ask. Well, it turns out that the binary format of
11530 locale data is occasionally incompatible from one libc version to
11533 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
11534 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
11535 For instance, a program linked against libc version 2.21 is unable to
11536 read locale data produced with libc 2.22; worse, that program
11537 @emph{aborts} instead of simply ignoring the incompatible locale
11538 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
11539 the incompatible locale data, which is already an improvement.}.
11540 Similarly, a program linked against libc 2.22 can read most, but not
11541 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
11542 data is incompatible); thus calls to @code{setlocale} may fail, but
11543 programs will not abort.
11545 The ``problem'' with Guix is that users have a lot of freedom: They can
11546 choose whether and when to upgrade software in their profiles, and might
11547 be using a libc version different from the one the system administrator
11548 used to build the system-wide locale data.
11550 Fortunately, unprivileged users can also install their own locale data
11551 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
11552 @code{GUIX_LOCPATH} and locale packages}).
11554 Still, it is best if the system-wide locale data at
11555 @file{/run/current-system/locale} is built for all the libc versions
11556 actually in use on the system, so that all the programs can access
11557 it---this is especially crucial on a multi-user system. To do that, the
11558 administrator can specify several libc packages in the
11559 @code{locale-libcs} field of @code{operating-system}:
11562 (use-package-modules base)
11566 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
11569 This example would lead to a system containing locale definitions for
11570 both libc 2.21 and the current version of libc in
11571 @file{/run/current-system/locale}.
11577 @cindex system services
11578 An important part of preparing an @code{operating-system} declaration is
11579 listing @dfn{system services} and their configuration (@pxref{Using the
11580 Configuration System}). System services are typically daemons launched
11581 when the system boots, or other actions needed at that time---e.g.,
11582 configuring network access.
11584 Guix has a broad definition of ``service'' (@pxref{Service
11585 Composition}), but many services are managed by the GNU@tie{}Shepherd
11586 (@pxref{Shepherd Services}). On a running system, the @command{herd}
11587 command allows you to list the available services, show their status,
11588 start and stop them, or do other specific operations (@pxref{Jump
11589 Start,,, shepherd, The GNU Shepherd Manual}). For example:
11595 The above command, run as @code{root}, lists the currently defined
11596 services. The @command{herd doc} command shows a synopsis of the given
11597 service and its associated actions:
11601 Run libc's name service cache daemon (nscd).
11603 # herd doc nscd action invalidate
11604 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
11607 The @command{start}, @command{stop}, and @command{restart} sub-commands
11608 have the effect you would expect. For instance, the commands below stop
11609 the nscd service and restart the Xorg display server:
11613 Service nscd has been stopped.
11614 # herd restart xorg-server
11615 Service xorg-server has been stopped.
11616 Service xorg-server has been started.
11619 The following sections document the available services, starting with
11620 the core services, that may be used in an @code{operating-system}
11624 * Base Services:: Essential system services.
11625 * Scheduled Job Execution:: The mcron service.
11626 * Log Rotation:: The rottlog service.
11627 * Networking Services:: Network setup, SSH daemon, etc.
11628 * X Window:: Graphical display.
11629 * Printing Services:: Local and remote printer support.
11630 * Desktop Services:: D-Bus and desktop services.
11631 * Sound Services:: ALSA and Pulseaudio services.
11632 * Database Services:: SQL databases, key-value stores, etc.
11633 * Mail Services:: IMAP, POP3, SMTP, and all that.
11634 * Messaging Services:: Messaging services.
11635 * Telephony Services:: Telephony services.
11636 * Monitoring Services:: Monitoring services.
11637 * Kerberos Services:: Kerberos services.
11638 * LDAP Services:: LDAP services.
11639 * Web Services:: Web servers.
11640 * Certificate Services:: TLS certificates via Let's Encrypt.
11641 * DNS Services:: DNS daemons.
11642 * VPN Services:: VPN daemons.
11643 * Network File System:: NFS related services.
11644 * Continuous Integration:: The Cuirass service.
11645 * Power Management Services:: Extending battery life.
11646 * Audio Services:: The MPD.
11647 * Virtualization Services:: Virtualization services.
11648 * Version Control Services:: Providing remote access to Git repositories.
11649 * Game Services:: Game servers.
11650 * Miscellaneous Services:: Other services.
11653 @node Base Services
11654 @subsection Base Services
11656 The @code{(gnu services base)} module provides definitions for the basic
11657 services that one expects from the system. The services exported by
11658 this module are listed below.
11660 @defvr {Scheme Variable} %base-services
11661 This variable contains a list of basic services (@pxref{Service Types
11662 and Services}, for more information on service objects) one would
11663 expect from the system: a login service (mingetty) on each tty, syslogd,
11664 the libc name service cache daemon (nscd), the udev device manager, and
11667 This is the default value of the @code{services} field of
11668 @code{operating-system} declarations. Usually, when customizing a
11669 system, you will want to append services to @code{%base-services}, like
11673 (append (list (service avahi-service-type)
11674 (service openssh-service-type))
11679 @defvr {Scheme Variable} special-files-service-type
11680 This is the service that sets up ``special files'' such as
11681 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
11683 The value associated with @code{special-files-service-type} services
11684 must be a list of tuples where the first element is the ``special file''
11685 and the second element is its target. By default it is:
11687 @cindex @file{/bin/sh}
11688 @cindex @file{sh}, in @file{/bin}
11690 `(("/bin/sh" ,(file-append bash "/bin/sh")))
11693 @cindex @file{/usr/bin/env}
11694 @cindex @file{env}, in @file{/usr/bin}
11695 If you want to add, say, @code{/usr/bin/env} to your system, you can
11699 `(("/bin/sh" ,(file-append bash "/bin/sh"))
11700 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
11703 Since this is part of @code{%base-services}, you can use
11704 @code{modify-services} to customize the set of special files
11705 (@pxref{Service Reference, @code{modify-services}}). But the simple way
11706 to add a special file is @i{via} the @code{extra-special-file} procedure
11710 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
11711 Use @var{target} as the ``special file'' @var{file}.
11713 For example, adding the following lines to the @code{services} field of
11714 your operating system declaration leads to a @file{/usr/bin/env}
11718 (extra-special-file "/usr/bin/env"
11719 (file-append coreutils "/bin/env"))
11723 @deffn {Scheme Procedure} host-name-service @var{name}
11724 Return a service that sets the host name to @var{name}.
11727 @deffn {Scheme Procedure} login-service @var{config}
11728 Return a service to run login according to @var{config}, a
11729 @code{<login-configuration>} object, which specifies the message of the day,
11730 among other things.
11733 @deftp {Data Type} login-configuration
11734 This is the data type representing the configuration of login.
11739 @cindex message of the day
11740 A file-like object containing the ``message of the day''.
11742 @item @code{allow-empty-passwords?} (default: @code{#t})
11743 Allow empty passwords by default so that first-time users can log in when
11744 the 'root' account has just been created.
11749 @deffn {Scheme Procedure} mingetty-service @var{config}
11750 Return a service to run mingetty according to @var{config}, a
11751 @code{<mingetty-configuration>} object, which specifies the tty to run, among
11755 @deftp {Data Type} mingetty-configuration
11756 This is the data type representing the configuration of Mingetty, which
11757 provides the default implementation of virtual console log-in.
11762 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
11764 @item @code{auto-login} (default: @code{#f})
11765 When true, this field must be a string denoting the user name under
11766 which the system automatically logs in. When it is @code{#f}, a
11767 user name and password must be entered to log in.
11769 @item @code{login-program} (default: @code{#f})
11770 This must be either @code{#f}, in which case the default log-in program
11771 is used (@command{login} from the Shadow tool suite), or a gexp denoting
11772 the name of the log-in program.
11774 @item @code{login-pause?} (default: @code{#f})
11775 When set to @code{#t} in conjunction with @var{auto-login}, the user
11776 will have to press a key before the log-in shell is launched.
11778 @item @code{mingetty} (default: @var{mingetty})
11779 The Mingetty package to use.
11784 @deffn {Scheme Procedure} agetty-service @var{config}
11785 Return a service to run agetty according to @var{config}, an
11786 @code{<agetty-configuration>} object, which specifies the tty to run,
11787 among other things.
11790 @deftp {Data Type} agetty-configuration
11791 This is the data type representing the configuration of agetty, which
11792 implements virtual and serial console log-in. See the @code{agetty(8)}
11793 man page for more information.
11798 The name of the console this agetty runs on, as a string---e.g.,
11799 @code{"ttyS0"}. This argument is optional, it will default to
11800 a reasonable default serial port used by the kernel Linux.
11802 For this, if there is a value for an option @code{agetty.tty} in the kernel
11803 command line, agetty will extract the device name of the serial port
11804 from it and use that.
11806 If not and if there is a value for an option @code{console} with a tty in
11807 the Linux command line, agetty will extract the device name of the
11808 serial port from it and use that.
11810 In both cases, agetty will leave the other serial device settings
11811 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
11814 @item @code{baud-rate} (default: @code{#f})
11815 A string containing a comma-separated list of one or more baud rates, in
11818 @item @code{term} (default: @code{#f})
11819 A string containing the value used for the @code{TERM} environment
11822 @item @code{eight-bits?} (default: @code{#f})
11823 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
11826 @item @code{auto-login} (default: @code{#f})
11827 When passed a login name, as a string, the specified user will be logged
11828 in automatically without prompting for their login name or password.
11830 @item @code{no-reset?} (default: @code{#f})
11831 When @code{#t}, don't reset terminal cflags (control modes).
11833 @item @code{host} (default: @code{#f})
11834 This accepts a string containing the "login_host", which will be written
11835 into the @file{/var/run/utmpx} file.
11837 @item @code{remote?} (default: @code{#f})
11838 When set to @code{#t} in conjunction with @var{host}, this will add an
11839 @code{-r} fakehost option to the command line of the login program
11840 specified in @var{login-program}.
11842 @item @code{flow-control?} (default: @code{#f})
11843 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
11845 @item @code{no-issue?} (default: @code{#f})
11846 When set to @code{#t}, the contents of the @file{/etc/issue} file will
11847 not be displayed before presenting the login prompt.
11849 @item @code{init-string} (default: @code{#f})
11850 This accepts a string that will be sent to the tty or modem before
11851 sending anything else. It can be used to initialize a modem.
11853 @item @code{no-clear?} (default: @code{#f})
11854 When set to @code{#t}, agetty will not clear the screen before showing
11857 @item @code{login-program} (default: (file-append shadow "/bin/login"))
11858 This must be either a gexp denoting the name of a log-in program, or
11859 unset, in which case the default value is the @command{login} from the
11862 @item @code{local-line} (default: @code{#f})
11863 Control the CLOCAL line flag. This accepts one of three symbols as
11864 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
11865 the default value chosen by agetty is @code{'auto}.
11867 @item @code{extract-baud?} (default: @code{#f})
11868 When set to @code{#t}, instruct agetty to try to extract the baud rate
11869 from the status messages produced by certain types of modems.
11871 @item @code{skip-login?} (default: @code{#f})
11872 When set to @code{#t}, do not prompt the user for a login name. This
11873 can be used with @var{login-program} field to use non-standard login
11876 @item @code{no-newline?} (default: @code{#f})
11877 When set to @code{#t}, do not print a newline before printing the
11878 @file{/etc/issue} file.
11880 @c Is this dangerous only when used with login-program, or always?
11881 @item @code{login-options} (default: @code{#f})
11882 This option accepts a string containing options that are passed to the
11883 login program. When used with the @var{login-program}, be aware that a
11884 malicious user could try to enter a login name containing embedded
11885 options that could be parsed by the login program.
11887 @item @code{login-pause} (default: @code{#f})
11888 When set to @code{#t}, wait for any key before showing the login prompt.
11889 This can be used in conjunction with @var{auto-login} to save memory by
11890 lazily spawning shells.
11892 @item @code{chroot} (default: @code{#f})
11893 Change root to the specified directory. This option accepts a directory
11896 @item @code{hangup?} (default: @code{#f})
11897 Use the Linux system call @code{vhangup} to do a virtual hangup of the
11898 specified terminal.
11900 @item @code{keep-baud?} (default: @code{#f})
11901 When set to @code{#t}, try to keep the existing baud rate. The baud
11902 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
11905 @item @code{timeout} (default: @code{#f})
11906 When set to an integer value, terminate if no user name could be read
11907 within @var{timeout} seconds.
11909 @item @code{detect-case?} (default: @code{#f})
11910 When set to @code{#t}, turn on support for detecting an uppercase-only
11911 terminal. This setting will detect a login name containing only
11912 uppercase letters as indicating an uppercase-only terminal and turn on
11913 some upper-to-lower case conversions. Note that this will not support
11914 Unicode characters.
11916 @item @code{wait-cr?} (default: @code{#f})
11917 When set to @code{#t}, wait for the user or modem to send a
11918 carriage-return or linefeed character before displaying
11919 @file{/etc/issue} or login prompt. This is typically used with the
11920 @var{init-string} option.
11922 @item @code{no-hints?} (default: @code{#f})
11923 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
11926 @item @code{no-hostname?} (default: @code{#f})
11927 By default, the hostname is printed. When this option is set to
11928 @code{#t}, no hostname will be shown at all.
11930 @item @code{long-hostname?} (default: @code{#f})
11931 By default, the hostname is only printed until the first dot. When this
11932 option is set to @code{#t}, the fully qualified hostname by
11933 @code{gethostname} or @code{getaddrinfo} is shown.
11935 @item @code{erase-characters} (default: @code{#f})
11936 This option accepts a string of additional characters that should be
11937 interpreted as backspace when the user types their login name.
11939 @item @code{kill-characters} (default: @code{#f})
11940 This option accepts a string that should be interpreted to mean "ignore
11941 all previous characters" (also called a "kill" character) when the user
11942 types their login name.
11944 @item @code{chdir} (default: @code{#f})
11945 This option accepts, as a string, a directory path that will be changed
11948 @item @code{delay} (default: @code{#f})
11949 This options accepts, as an integer, the number of seconds to sleep
11950 before opening the tty and displaying the login prompt.
11952 @item @code{nice} (default: @code{#f})
11953 This option accepts, as an integer, the nice value with which to run the
11954 @command{login} program.
11956 @item @code{extra-options} (default: @code{'()})
11957 This option provides an "escape hatch" for the user to provide arbitrary
11958 command-line arguments to @command{agetty} as a list of strings.
11963 @deffn {Scheme Procedure} kmscon-service-type @var{config}
11964 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
11965 according to @var{config}, a @code{<kmscon-configuration>} object, which
11966 specifies the tty to run, among other things.
11969 @deftp {Data Type} kmscon-configuration
11970 This is the data type representing the configuration of Kmscon, which
11971 implements virtual console log-in.
11975 @item @code{virtual-terminal}
11976 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
11978 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
11979 A gexp denoting the name of the log-in program. The default log-in program is
11980 @command{login} from the Shadow tool suite.
11982 @item @code{login-arguments} (default: @code{'("-p")})
11983 A list of arguments to pass to @command{login}.
11985 @item @code{auto-login} (default: @code{#f})
11986 When passed a login name, as a string, the specified user will be logged
11987 in automatically without prompting for their login name or password.
11989 @item @code{hardware-acceleration?} (default: #f)
11990 Whether to use hardware acceleration.
11992 @item @code{kmscon} (default: @var{kmscon})
11993 The Kmscon package to use.
11998 @cindex name service cache daemon
12000 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
12001 [#:name-services '()]
12002 Return a service that runs the libc name service cache daemon (nscd) with the
12003 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
12004 Service Switch}, for an example.
12006 For convenience, the Shepherd service for nscd provides the following actions:
12010 @cindex cache invalidation, nscd
12011 @cindex nscd, cache invalidation
12012 This invalidate the given cache. For instance, running:
12015 herd invalidate nscd hosts
12019 invalidates the host name lookup cache of nscd.
12022 Running @command{herd statistics nscd} displays information about nscd usage
12028 @defvr {Scheme Variable} %nscd-default-configuration
12029 This is the default @code{<nscd-configuration>} value (see below) used
12030 by @code{nscd-service}. It uses the caches defined by
12031 @var{%nscd-default-caches}; see below.
12034 @deftp {Data Type} nscd-configuration
12035 This is the data type representing the name service cache daemon (nscd)
12040 @item @code{name-services} (default: @code{'()})
12041 List of packages denoting @dfn{name services} that must be visible to
12042 the nscd---e.g., @code{(list @var{nss-mdns})}.
12044 @item @code{glibc} (default: @var{glibc})
12045 Package object denoting the GNU C Library providing the @command{nscd}
12048 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
12049 Name of the nscd log file. This is where debugging output goes when
12050 @code{debug-level} is strictly positive.
12052 @item @code{debug-level} (default: @code{0})
12053 Integer denoting the debugging levels. Higher numbers mean that more
12054 debugging output is logged.
12056 @item @code{caches} (default: @var{%nscd-default-caches})
12057 List of @code{<nscd-cache>} objects denoting things to be cached; see
12063 @deftp {Data Type} nscd-cache
12064 Data type representing a cache database of nscd and its parameters.
12068 @item @code{database}
12069 This is a symbol representing the name of the database to be cached.
12070 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
12071 @code{services}, which designate the corresponding NSS database
12072 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
12074 @item @code{positive-time-to-live}
12075 @itemx @code{negative-time-to-live} (default: @code{20})
12076 A number representing the number of seconds during which a positive or
12077 negative lookup result remains in cache.
12079 @item @code{check-files?} (default: @code{#t})
12080 Whether to check for updates of the files corresponding to
12083 For instance, when @var{database} is @code{hosts}, setting this flag
12084 instructs nscd to check for updates in @file{/etc/hosts} and to take
12087 @item @code{persistent?} (default: @code{#t})
12088 Whether the cache should be stored persistently on disk.
12090 @item @code{shared?} (default: @code{#t})
12091 Whether the cache should be shared among users.
12093 @item @code{max-database-size} (default: 32@tie{}MiB)
12094 Maximum size in bytes of the database cache.
12096 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
12097 @c settings, so leave them out.
12102 @defvr {Scheme Variable} %nscd-default-caches
12103 List of @code{<nscd-cache>} objects used by default by
12104 @code{nscd-configuration} (see above).
12106 It enables persistent and aggressive caching of service and host name
12107 lookups. The latter provides better host name lookup performance,
12108 resilience in the face of unreliable name servers, and also better
12109 privacy---often the result of host name lookups is in local cache, so
12110 external name servers do not even need to be queried.
12113 @anchor{syslog-configuration-type}
12116 @deftp {Data Type} syslog-configuration
12117 This data type represents the configuration of the syslog daemon.
12120 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12121 The syslog daemon to use.
12123 @item @code{config-file} (default: @code{%default-syslog.conf})
12124 The syslog configuration file to use.
12129 @anchor{syslog-service}
12131 @deffn {Scheme Procedure} syslog-service @var{config}
12132 Return a service that runs a syslog daemon according to @var{config}.
12134 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12135 information on the configuration file syntax.
12138 @defvr {Scheme Variable} guix-service-type
12139 This is the type of the service that runs the build daemon,
12140 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12141 @code{guix-configuration} record as described below.
12144 @anchor{guix-configuration-type}
12145 @deftp {Data Type} guix-configuration
12146 This data type represents the configuration of the Guix build daemon.
12147 @xref{Invoking guix-daemon}, for more information.
12150 @item @code{guix} (default: @var{guix})
12151 The Guix package to use.
12153 @item @code{build-group} (default: @code{"guixbuild"})
12154 Name of the group for build user accounts.
12156 @item @code{build-accounts} (default: @code{10})
12157 Number of build user accounts to create.
12159 @item @code{authorize-key?} (default: @code{#t})
12160 @cindex substitutes, authorization thereof
12161 Whether to authorize the substitute keys listed in
12162 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12163 (@pxref{Substitutes}).
12165 @vindex %default-authorized-guix-keys
12166 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12167 The list of authorized key files for archive imports, as a list of
12168 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12169 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12171 @item @code{use-substitutes?} (default: @code{#t})
12172 Whether to use substitutes.
12174 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12175 The list of URLs where to look for substitutes by default.
12177 @item @code{max-silent-time} (default: @code{0})
12178 @itemx @code{timeout} (default: @code{0})
12179 The number of seconds of silence and the number of seconds of activity,
12180 respectively, after which a build process times out. A value of zero
12181 disables the timeout.
12183 @item @code{log-compression} (default: @code{'bzip2})
12184 The type of compression used for build logs---one of @code{gzip},
12185 @code{bzip2}, or @code{none}.
12187 @item @code{extra-options} (default: @code{'()})
12188 List of extra command-line options for @command{guix-daemon}.
12190 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12191 File where @command{guix-daemon}'s standard output and standard error
12194 @item @code{http-proxy} (default: @code{#f})
12195 The HTTP proxy used for downloading fixed-output derivations and
12198 @item @code{tmpdir} (default: @code{#f})
12199 A directory path where the @command{guix-daemon} will perform builds.
12204 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12205 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12206 udev rules can be provided as a list of files through the @var{rules}
12207 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12208 @code{(gnu services base)} simplify the creation of such rule files.
12211 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12212 Return a udev-rule file named @var{file-name} containing the rules
12213 defined by the @var{contents} literal.
12215 In the following example, a rule for a USB device is defined to be
12216 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12217 upon detecting a USB device with a given product identifier.
12220 (define %example-udev-rule
12222 "90-usb-thing.rules"
12223 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12224 "ATTR@{product@}==\"Example\", "
12225 "RUN+=\"/path/to/script\"")))
12228 The @command{herd rules udev} command, as root, returns the name of the
12229 directory containing all the active udev rules.
12232 Here we show how the default @var{udev-service} can be extended with it.
12238 (modify-services %desktop-services
12239 (udev-service-type config =>
12240 (udev-configuration (inherit config)
12241 (rules (append (udev-configuration-rules config)
12242 (list %example-udev-rule))))))))
12245 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12246 Return a udev file named @var{file-name} containing the rules defined
12247 within @var{file}, a file-like object.
12249 The following example showcases how we can use an existing rule file.
12252 (use-modules (guix download) ;for url-fetch
12253 (guix packages) ;for origin
12256 (define %android-udev-rules
12258 "51-android-udev.rules"
12259 (let ((version "20170910"))
12262 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12263 "android-udev-rules/" version "/51-android.rules"))
12265 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12269 Additionally, Guix package definitions can be included in @var{rules} in
12270 order to extend the udev rules with the definitions found under their
12271 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12272 @var{file->udev-rule} example, we could have used the
12273 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12274 packages android)} module.
12276 The following example shows how to use the @var{android-udev-rules}
12277 package so that the Android tool @command{adb} can detect devices
12278 without root privileges. It also details how to create the
12279 @code{adbusers} group, which is required for the proper functioning of
12280 the rules defined within the @var{android-udev-rules} package. To
12281 create such a group, we must define it both as part of the
12282 @var{supplementary-groups} of our @var{user-account} declaration, as
12283 well as in the @var{groups} field of the @var{operating-system} record.
12286 (use-modules (gnu packages android) ;for android-udev-rules
12287 (gnu system shadow) ;for user-group
12292 (users (cons (user-acount
12294 (supplementary-groups
12295 '("adbusers" ;for adb
12296 "wheel" "netdev" "audio" "video"))
12299 (groups (cons (user-group (system? #t) (name "adbusers"))
12305 (modify-services %desktop-services
12308 (udev-configuration (inherit config)
12309 (rules (cons android-udev-rules
12310 (udev-configuration-rules config))))))))
12313 @defvr {Scheme Variable} urandom-seed-service-type
12314 Save some entropy in @var{%random-seed-file} to seed @file{/dev/urandom}
12315 when rebooting. It also tries to seed @file{/dev/urandom} from
12316 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12320 @defvr {Scheme Variable} %random-seed-file
12321 This is the name of the file where some random bytes are saved by
12322 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12323 It defaults to @file{/var/lib/random-seed}.
12328 @defvr {Scheme Variable} gpm-service-type
12329 This is the type of the service that runs GPM, the @dfn{general-purpose
12330 mouse daemon}, which provides mouse support to the Linux console. GPM
12331 allows users to use the mouse in the console, notably to select, copy,
12334 The value for services of this type must be a @code{gpm-configuration}
12335 (see below). This service is not part of @code{%base-services}.
12338 @deftp {Data Type} gpm-configuration
12339 Data type representing the configuration of GPM.
12342 @item @code{options} (default: @code{%default-gpm-options})
12343 Command-line options passed to @command{gpm}. The default set of
12344 options instruct @command{gpm} to listen to mouse events on
12345 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12348 @item @code{gpm} (default: @code{gpm})
12349 The GPM package to use.
12354 @anchor{guix-publish-service-type}
12355 @deffn {Scheme Variable} guix-publish-service-type
12356 This is the service type for @command{guix publish} (@pxref{Invoking
12357 guix publish}). Its value must be a @code{guix-publish-configuration}
12358 object, as described below.
12360 This assumes that @file{/etc/guix} already contains a signing key pair as
12361 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12362 archive}). If that is not the case, the service will fail to start.
12365 @deftp {Data Type} guix-publish-configuration
12366 Data type representing the configuration of the @code{guix publish}
12370 @item @code{guix} (default: @code{guix})
12371 The Guix package to use.
12373 @item @code{port} (default: @code{80})
12374 The TCP port to listen for connections.
12376 @item @code{host} (default: @code{"localhost"})
12377 The host (and thus, network interface) to listen to. Use
12378 @code{"0.0.0.0"} to listen on all the network interfaces.
12380 @item @code{compression} (default: @code{'(("gzip" 3))})
12381 This is a list of compression method/level tuple used when compressing
12382 substitutes. For example, to compress all substitutes with @emph{both} lzip
12383 at level 7 and gzip at level 9, write:
12386 '(("lzip" 7) ("gzip" 9))
12389 Level 9 achieves the best compression ratio at the expense of increased CPU
12390 usage, whereas level 1 achieves fast compression.
12392 An empty list disables compression altogether.
12394 @item @code{nar-path} (default: @code{"nar"})
12395 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
12396 publish, @code{--nar-path}}, for details.
12398 @item @code{cache} (default: @code{#f})
12399 When it is @code{#f}, disable caching and instead generate archives on
12400 demand. Otherwise, this should be the name of a directory---e.g.,
12401 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
12402 archives and meta-data ready to be sent. @xref{Invoking guix publish,
12403 @option{--cache}}, for more information on the tradeoffs involved.
12405 @item @code{workers} (default: @code{#f})
12406 When it is an integer, this is the number of worker threads used for
12407 caching; when @code{#f}, the number of processors is used.
12408 @xref{Invoking guix publish, @option{--workers}}, for more information.
12410 @item @code{ttl} (default: @code{#f})
12411 When it is an integer, this denotes the @dfn{time-to-live} in seconds
12412 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
12413 for more information.
12417 @anchor{rngd-service}
12418 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
12419 [#:device "/dev/hwrng"]
12420 Return a service that runs the @command{rngd} program from @var{rng-tools}
12421 to add @var{device} to the kernel's entropy pool. The service will fail if
12422 @var{device} does not exist.
12425 @anchor{pam-limits-service}
12426 @cindex session limits
12431 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
12433 Return a service that installs a configuration file for the
12434 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
12435 @code{pam_limits} module}. The procedure optionally takes a list of
12436 @code{pam-limits-entry} values, which can be used to specify
12437 @code{ulimit} limits and nice priority limits to user sessions.
12439 The following limits definition sets two hard and soft limits for all
12440 login sessions of users in the @code{realtime} group:
12443 (pam-limits-service
12445 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
12446 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
12449 The first entry increases the maximum realtime priority for
12450 non-privileged processes; the second entry lifts any restriction of the
12451 maximum address space that can be locked in memory. These settings are
12452 commonly used for real-time audio systems.
12455 @node Scheduled Job Execution
12456 @subsection Scheduled Job Execution
12460 @cindex scheduling jobs
12461 The @code{(gnu services mcron)} module provides an interface to
12462 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
12463 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
12464 Unix @command{cron} daemon; the main difference is that it is
12465 implemented in Guile Scheme, which provides a lot of flexibility when
12466 specifying the scheduling of jobs and their actions.
12468 The example below defines an operating system that runs the
12469 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
12470 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
12471 well as the @command{mkid} command on behalf of an unprivileged user
12472 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
12473 gexps to introduce job definitions that are passed to mcron
12474 (@pxref{G-Expressions}).
12477 (use-modules (guix) (gnu) (gnu services mcron))
12478 (use-package-modules base idutils)
12480 (define updatedb-job
12481 ;; Run 'updatedb' at 3AM every day. Here we write the
12482 ;; job's action as a Scheme procedure.
12483 #~(job '(next-hour '(3))
12485 (execl (string-append #$findutils "/bin/updatedb")
12487 "--prunepaths=/tmp /var/tmp /gnu/store"))))
12489 (define garbage-collector-job
12490 ;; Collect garbage 5 minutes after midnight every day.
12491 ;; The job's action is a shell command.
12492 #~(job "5 0 * * *" ;Vixie cron syntax
12495 (define idutils-job
12496 ;; Update the index database as user "charlie" at 12:15PM
12497 ;; and 19:15PM. This runs from the user's home directory.
12498 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
12499 (string-append #$idutils "/bin/mkid src")
12504 (services (cons (service mcron-service-type
12505 (mcron-configuration
12506 (jobs (list garbage-collector-job
12512 For more complex jobs defined in Scheme where you need control over the top
12513 level, for instance to introduce a @code{use-modules} form, you can move your
12514 code to a separate program using the @code{program-file} procedure of the
12515 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
12519 (define %battery-alert-job
12520 ;; Beep when the battery percentage falls below %MIN-LEVEL.
12522 '(next-minute (range 0 60 1))
12524 "battery-alert.scm"
12525 (with-imported-modules (source-module-closure
12526 '((guix build utils)))
12528 (define %min-level 20)
12529 (use-modules (guix build utils)
12532 (ice-9 textual-ports)
12534 (setenv "LC_ALL" "C") ;ensure English output
12535 (and-let* ((input-pipe (open-pipe*
12537 #$(file-append acpi "/bin/acpi")))
12538 (output (get-string-all input-pipe))
12539 (m (string-match "Discharging, ([0-9]+)%" output))
12540 (level (string->number (match:substring m 1)))
12541 ((< level %min-level)))
12542 (format #t "warning: Battery level is low (~a%)~%" level)
12543 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
12546 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
12547 for more information on mcron job specifications. Below is the
12548 reference of the mcron service.
12550 On a running system, you can use the @code{schedule} action of the service to
12551 visualize the mcron jobs that will be executed next:
12554 # herd schedule mcron
12558 The example above lists the next five tasks that will be executed, but you can
12559 also specify the number of tasks to display:
12562 # herd schedule mcron 10
12565 @defvr {Scheme Variable} mcron-service-type
12566 This is the type of the @code{mcron} service, whose value is an
12567 @code{mcron-configuration} object.
12569 This service type can be the target of a service extension that provides
12570 it additional job specifications (@pxref{Service Composition}). In
12571 other words, it is possible to define services that provide additional
12575 @deftp {Data Type} mcron-configuration
12576 Data type representing the configuration of mcron.
12579 @item @code{mcron} (default: @var{mcron})
12580 The mcron package to use.
12583 This is a list of gexps (@pxref{G-Expressions}), where each gexp
12584 corresponds to an mcron job specification (@pxref{Syntax, mcron job
12585 specifications,, mcron, GNU@tie{}mcron}).
12591 @subsection Log Rotation
12594 @cindex log rotation
12596 Log files such as those found in @file{/var/log} tend to grow endlessly,
12597 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
12598 their contents in separate files, possibly compressed. The @code{(gnu
12599 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
12600 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
12602 The example below defines an operating system that provides log rotation
12603 with the default settings, for commonly encountered log files.
12606 (use-modules (guix) (gnu))
12607 (use-service-modules admin mcron)
12608 (use-package-modules base idutils)
12612 (services (cons (service rottlog-service-type)
12616 @defvr {Scheme Variable} rottlog-service-type
12617 This is the type of the Rottlog service, whose value is a
12618 @code{rottlog-configuration} object.
12620 Other services can extend this one with new @code{log-rotation} objects
12621 (see below), thereby augmenting the set of files to be rotated.
12623 This service type can define mcron jobs (@pxref{Scheduled Job
12624 Execution}) to run the rottlog service.
12627 @deftp {Data Type} rottlog-configuration
12628 Data type representing the configuration of rottlog.
12631 @item @code{rottlog} (default: @code{rottlog})
12632 The Rottlog package to use.
12634 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
12635 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
12636 rottlog, GNU Rot[t]log Manual}).
12638 @item @code{rotations} (default: @code{%default-rotations})
12639 A list of @code{log-rotation} objects as defined below.
12642 This is a list of gexps where each gexp corresponds to an mcron job
12643 specification (@pxref{Scheduled Job Execution}).
12647 @deftp {Data Type} log-rotation
12648 Data type representing the rotation of a group of log files.
12650 Taking an example from the Rottlog manual (@pxref{Period Related File
12651 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
12657 (files '("/var/log/apache/*"))
12658 (options '("storedir apache-archives"
12664 The list of fields is as follows:
12667 @item @code{frequency} (default: @code{'weekly})
12668 The log rotation frequency, a symbol.
12671 The list of files or file glob patterns to rotate.
12673 @item @code{options} (default: @code{'()})
12674 The list of rottlog options for this rotation (@pxref{Configuration
12675 parameters,,, rottlog, GNU Rot[t]lg Manual}).
12677 @item @code{post-rotate} (default: @code{#f})
12678 Either @code{#f} or a gexp to execute once the rotation has completed.
12682 @defvr {Scheme Variable} %default-rotations
12683 Specifies weekly rotation of @var{%rotated-files} and of
12684 @file{/var/log/guix-daemon.log}.
12687 @defvr {Scheme Variable} %rotated-files
12688 The list of syslog-controlled files to be rotated. By default it is:
12689 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
12690 "/var/log/maillog")}.
12693 @node Networking Services
12694 @subsection Networking Services
12696 The @code{(gnu services networking)} module provides services to configure
12697 the network interface.
12699 @cindex DHCP, networking service
12700 @defvr {Scheme Variable} dhcp-client-service-type
12701 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
12702 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
12703 is the DHCP client package to use, @code{isc-dhcp} by default.
12706 @deffn {Scheme Procedure} dhcpd-service-type
12707 This type defines a service that runs a DHCP daemon. To create a
12708 service of this type, you must supply a @code{<dhcpd-configuration>}.
12712 (service dhcpd-service-type
12713 (dhcpd-configuration
12714 (config-file (local-file "my-dhcpd.conf"))
12715 (interfaces '("enp0s25"))))
12719 @deftp {Data Type} dhcpd-configuration
12721 @item @code{package} (default: @code{isc-dhcp})
12722 The package that provides the DHCP daemon. This package is expected to
12723 provide the daemon at @file{sbin/dhcpd} relative to its output
12724 directory. The default package is the
12725 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
12726 @item @code{config-file} (default: @code{#f})
12727 The configuration file to use. This is required. It will be passed to
12728 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
12729 object (@pxref{G-Expressions, file-like objects}). See @code{man
12730 dhcpd.conf} for details on the configuration file syntax.
12731 @item @code{version} (default: @code{"4"})
12732 The DHCP version to use. The ISC DHCP server supports the values ``4'',
12733 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
12734 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
12736 @item @code{run-directory} (default: @code{"/run/dhcpd"})
12737 The run directory to use. At service activation time, this directory
12738 will be created if it does not exist.
12739 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
12740 The PID file to use. This corresponds to the @code{-pf} option of
12741 @code{dhcpd}. See @code{man dhcpd} for details.
12742 @item @code{interfaces} (default: @code{'()})
12743 The names of the network interfaces on which dhcpd should listen for
12744 broadcasts. If this list is not empty, then its elements (which must be
12745 strings) will be appended to the @code{dhcpd} invocation when starting
12746 the daemon. It may not be necessary to explicitly specify any
12747 interfaces here; see @code{man dhcpd} for details.
12751 @defvr {Scheme Variable} static-networking-service-type
12752 This is the type for statically-configured network interfaces.
12753 @c TODO Document <static-networking> data structures.
12756 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
12757 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
12758 [#:requirement @code{'(udev)}]
12759 Return a service that starts @var{interface} with address @var{ip}. If
12760 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
12761 it must be a string specifying the default network gateway. @var{requirement}
12762 can be used to declare a dependency on another service before configuring the
12765 This procedure can be called several times, one for each network
12766 interface of interest. Behind the scenes what it does is extend
12767 @code{static-networking-service-type} with additional network interfaces
12773 (static-networking-service "eno1" "192.168.1.82"
12774 #:gateway "192.168.1.2"
12775 #:name-servers '("192.168.1.2"))
12782 @cindex network management
12783 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
12784 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
12785 management daemon that aims to simplify wired and wireless networking.
12787 This service adds the @var{wicd} package to the global profile, providing
12788 several commands to interact with the daemon and configure networking:
12789 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
12790 and @command{wicd-curses} user interfaces.
12793 @cindex ModemManager
12795 @defvr {Scheme Variable} modem-manager-service-type
12796 This is the service type for the
12797 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
12798 service. The value for this service type is a
12799 @code{modem-manager-configuration} record.
12801 This service is part of @code{%desktop-services} (@pxref{Desktop
12805 @deftp {Data Type} modem-manager-configuration
12806 Data type representing the configuration of ModemManager.
12809 @item @code{modem-manager} (default: @code{modem-manager})
12810 The ModemManager package to use.
12815 @cindex USB_ModeSwitch
12816 @cindex Modeswitching
12818 @defvr {Scheme Variable} usb-modeswitch-service-type
12819 This is the service type for the
12820 @uref{http://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
12821 value for this service type is a @code{usb-modeswitch-configuration} record.
12823 When plugged in, some USB modems (and other USB devices) initially present
12824 themselves as a read-only storage medium and not as a modem. They need to be
12825 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
12826 installs udev rules to automatically modeswitch these devices when they are
12829 This service is part of @code{%desktop-services} (@pxref{Desktop
12833 @deftp {Data Type} usb-modeswitch-configuration
12834 Data type representing the configuration of USB_ModeSwitch.
12837 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
12838 The USB_ModeSwitch package providing the binaries for modeswitching.
12840 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
12841 The package providing the device data and udev rules file used by
12844 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
12845 Which config file to use for the USB_ModeSwitch dispatcher. By default the
12846 config file shipped with USB_ModeSwitch is used which disables logging to
12847 @file{/var/log} among other default settings. If set to @code{#f}, no config
12853 @cindex NetworkManager
12855 @defvr {Scheme Variable} network-manager-service-type
12856 This is the service type for the
12857 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
12858 service. The value for this service type is a
12859 @code{network-manager-configuration} record.
12861 This service is part of @code{%desktop-services} (@pxref{Desktop
12865 @deftp {Data Type} network-manager-configuration
12866 Data type representing the configuration of NetworkManager.
12869 @item @code{network-manager} (default: @code{network-manager})
12870 The NetworkManager package to use.
12872 @item @code{dns} (default: @code{"default"})
12873 Processing mode for DNS, which affects how NetworkManager uses the
12874 @code{resolv.conf} configuration file.
12878 NetworkManager will update @code{resolv.conf} to reflect the nameservers
12879 provided by currently active connections.
12882 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
12883 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
12884 then update @code{resolv.conf} to point to the local nameserver.
12886 With this setting, you can share your network connection. For example when
12887 you want to share your network connection to another laptop @i{via} an
12888 Ethernet cable, you can open @command{nm-connection-editor} and configure the
12889 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
12890 and reestablish the connection (or reboot).
12892 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
12893 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
12894 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
12895 browser on your host system, or connect to the VM @i{via} SSH
12896 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
12897 host-to-guest connection, run this command once:
12900 nmcli connection add type tun \
12901 connection.interface-name tap0 \
12902 tun.mode tap tun.owner $(id -u) \
12903 ipv4.method shared \
12904 ipv4.addresses 172.28.112.1/24
12907 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
12908 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
12909 @command{qemu-system-...}.
12912 NetworkManager will not modify @code{resolv.conf}.
12915 @item @code{vpn-plugins} (default: @code{'()})
12916 This is the list of available plugins for virtual private networks
12917 (VPNs). An example of this is the @code{network-manager-openvpn}
12918 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
12924 @deffn {Scheme Variable} connman-service-type
12925 This is the service type to run @url{https://01.org/connman,Connman},
12926 a network connection manager.
12928 Its value must be an
12929 @code{connman-configuration} record as in this example:
12932 (service connman-service-type
12933 (connman-configuration
12934 (disable-vpn? #t)))
12937 See below for details about @code{connman-configuration}.
12940 @deftp {Data Type} connman-configuration
12941 Data Type representing the configuration of connman.
12944 @item @code{connman} (default: @var{connman})
12945 The connman package to use.
12947 @item @code{disable-vpn?} (default: @code{#f})
12948 When true, disable connman's vpn plugin.
12952 @cindex WPA Supplicant
12953 @defvr {Scheme Variable} wpa-supplicant-service-type
12954 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
12955 supplicant}, an authentication daemon required to authenticate against
12956 encrypted WiFi or ethernet networks.
12959 @deftp {Data Type} wpa-supplicant-configuration
12960 Data type representing the configuration of WPA Supplicant.
12962 It takes the following parameters:
12965 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
12966 The WPA Supplicant package to use.
12968 @item @code{dbus?} (default: @code{#t})
12969 Whether to listen for requests on D-Bus.
12971 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
12972 Where to store the PID file.
12974 @item @code{interface} (default: @code{#f})
12975 If this is set, it must specify the name of a network interface that
12976 WPA supplicant will control.
12978 @item @code{config-file} (default: @code{#f})
12979 Optional configuration file to use.
12981 @item @code{extra-options} (default: @code{'()})
12982 List of additional command-line arguments to pass to the daemon.
12987 @defvr {Scheme Variable} iptables-service-type
12988 This is the service type to set up an iptables configuration. iptables is a
12989 packet filtering framework supported by the Linux kernel. This service
12990 supports configuring iptables for both IPv4 and IPv6. A simple example
12991 configuration rejecting all incoming connections except those to the ssh port
12995 (service iptables-service-type
12996 (iptables-configuration
12997 (ipv4-rules (plain-file "iptables.rules" "*filter
13001 -A INPUT -p tcp --dport 22 -j ACCEPT
13002 -A INPUT -j REJECT --reject-with icmp-port-unreachable
13005 (ipv6-rules (plain-file "ip6tables.rules" "*filter
13009 -A INPUT -p tcp --dport 22 -j ACCEPT
13010 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
13016 @deftp {Data Type} iptables-configuration
13017 The data type representing the configuration of iptables.
13020 @item @code{iptables} (default: @code{iptables})
13021 The iptables package that provides @code{iptables-restore} and
13022 @code{ip6tables-restore}.
13023 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
13024 The iptables rules to use. It will be passed to @code{iptables-restore}.
13025 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13027 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
13028 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
13029 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13034 @cindex NTP (Network Time Protocol), service
13035 @cindex ntpd, service for the Network Time Protocol daemon
13036 @cindex real time clock
13037 @defvr {Scheme Variable} ntp-service-type
13038 This is the type of the service running the @uref{http://www.ntp.org,
13039 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
13040 system clock synchronized with that of the specified NTP servers.
13042 The value of this service is an @code{ntpd-configuration} object, as described
13046 @deftp {Data Type} ntp-configuration
13047 This is the data type for the NTP service configuration.
13050 @item @code{servers} (default: @code{%ntp-servers})
13051 This is the list of servers (@code{<ntp-server>} records) with which
13052 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
13055 @item @code{allow-large-adjustment?} (default: @code{#t})
13056 This determines whether @command{ntpd} is allowed to make an initial
13057 adjustment of more than 1,000 seconds.
13059 @item @code{ntp} (default: @code{ntp})
13060 The NTP package to use.
13064 @defvr {Scheme Variable} %ntp-servers
13065 List of host names used as the default NTP servers. These are servers of the
13066 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
13069 @deftp {Data Type} ntp-server
13070 The data type representing the configuration of a NTP server.
13073 @item @code{type} (default: @code{'server})
13074 The type of the NTP server, given as a symbol. One of @code{'pool},
13075 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
13077 @item @code{address}
13078 The address of the server, as a string.
13080 @item @code{options}
13081 NTPD options to use with that specific server, given as a list of option names
13082 and/or of option names and values tuples. The following example define a server
13083 to use with the options @option{iburst} and @option{prefer}, as well as
13084 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
13089 (address "some.ntp.server.org")
13090 (options `(iburst (version 3) (maxpoll 16) prefer))))
13096 @deffn {Scheme Procedure} openntpd-service-type
13097 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
13098 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
13099 clock synchronized with that of the given servers.
13103 openntpd-service-type
13104 (openntpd-configuration
13105 (listen-on '("127.0.0.1" "::1"))
13106 (sensor '("udcf0 correction 70000"))
13107 (constraint-from '("www.gnu.org"))
13108 (constraints-from '("https://www.google.com/"))
13109 (allow-large-adjustment? #t)))
13114 @defvr {Scheme Variable} %openntpd-servers
13115 This variable is a list of the server addresses defined in
13116 @var{%ntp-servers}.
13119 @deftp {Data Type} openntpd-configuration
13121 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
13122 The openntpd executable to use.
13123 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
13124 A list of local IP addresses or hostnames the ntpd daemon should listen on.
13125 @item @code{query-from} (default: @code{'()})
13126 A list of local IP address the ntpd daemon should use for outgoing queries.
13127 @item @code{sensor} (default: @code{'()})
13128 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
13129 will listen to each sensor that actually exists and ignore non-existent ones.
13130 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
13132 @item @code{server} (default: @code{'()})
13133 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
13134 @item @code{servers} (default: @var{%openntp-servers})
13135 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
13136 @item @code{constraint-from} (default: @code{'()})
13137 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
13138 This time information is not used for precision but acts as an authenticated
13139 constraint, thereby reducing the impact of unauthenticated NTP
13140 man-in-the-middle attacks.
13141 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
13143 @item @code{constraints-from} (default: @code{'()})
13144 As with constraint from, specify a list of URLs, IP addresses or hostnames of
13145 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
13146 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
13147 @item @code{allow-large-adjustment?} (default: @code{#f})
13148 Determines if @code{ntpd} is allowed to make an initial adjustment of more
13154 @deffn {Scheme variable} inetd-service-type
13155 This service runs the @command{inetd} (@pxref{inetd invocation,,,
13156 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
13157 connections on internet sockets, and lazily starts the specified server
13158 program when a connection is made on one of these sockets.
13160 The value of this service is an @code{inetd-configuration} object. The
13161 following example configures the @command{inetd} daemon to provide the
13162 built-in @command{echo} service, as well as an smtp service which
13163 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
13164 gateway @code{hostname}:
13169 (inetd-configuration
13173 (socket-type 'stream)
13180 (socket-type 'stream)
13184 (program (file-append openssh "/bin/ssh"))
13186 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13187 "-W" "smtp-server:25" "user@@hostname")))))
13190 See below for more details about @code{inetd-configuration}.
13193 @deftp {Data Type} inetd-configuration
13194 Data type representing the configuration of @command{inetd}.
13197 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13198 The @command{inetd} executable to use.
13200 @item @code{entries} (default: @code{'()})
13201 A list of @command{inetd} service entries. Each entry should be created
13202 by the @code{inetd-entry} constructor.
13206 @deftp {Data Type} inetd-entry
13207 Data type representing an entry in the @command{inetd} configuration.
13208 Each entry corresponds to a socket where @command{inetd} will listen for
13212 @item @code{node} (default: @code{#f})
13213 Optional string, a comma-separated list of local addresses
13214 @command{inetd} should use when listening for this service.
13215 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13216 description of all options.
13218 A string, the name must correspond to an entry in @code{/etc/services}.
13219 @item @code{socket-type}
13220 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13222 @item @code{protocol}
13223 A string, must correspond to an entry in @code{/etc/protocols}.
13224 @item @code{wait?} (default: @code{#t})
13225 Whether @command{inetd} should wait for the server to exit before
13226 listening to new service requests.
13228 A string containing the user (and, optionally, group) name of the user
13229 as whom the server should run. The group name can be specified in a
13230 suffix, separated by a colon or period, i.e.@: @code{"user"},
13231 @code{"user:group"} or @code{"user.group"}.
13232 @item @code{program} (default: @code{"internal"})
13233 The server program which will serve the requests, or @code{"internal"}
13234 if @command{inetd} should use a built-in service.
13235 @item @code{arguments} (default: @code{'()})
13236 A list strings or file-like objects, which are the server program's
13237 arguments, starting with the zeroth argument, i.e.@: the name of the
13238 program itself. For @command{inetd}'s internal services, this entry
13239 must be @code{'()} or @code{'("internal")}.
13242 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13243 detailed discussion of each configuration field.
13247 @defvr {Scheme Variable} tor-service-type
13248 This is the type for a service that runs the @uref{https://torproject.org,
13249 Tor} anonymous networking daemon. The service is configured using a
13250 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
13251 @code{tor} unprivileged user, which is a member of the @code{tor} group.
13255 @deftp {Data Type} tor-configuration
13257 @item @code{tor} (default: @code{tor})
13258 The package that provides the Tor daemon. This package is expected to provide
13259 the daemon at @file{bin/tor} relative to its output directory. The default
13260 package is the @uref{https://www.torproject.org, Tor Project's}
13263 @item @code{config-file} (default: @code{(plain-file "empty" "")})
13264 The configuration file to use. It will be appended to a default configuration
13265 file, and the final configuration file will be passed to @code{tor} via its
13266 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
13267 file-like objects}). See @code{man tor} for details on the configuration file
13270 @item @code{hidden-services} (default: @code{'()})
13271 The list of @code{<hidden-service>} records to use. For any hidden service
13272 you include in this list, appropriate configuration to enable the hidden
13273 service will be automatically added to the default configuration file. You
13274 may conveniently create @code{<hidden-service>} records using the
13275 @code{tor-hidden-service} procedure described below.
13277 @item @code{socks-socket-type} (default: @code{'tcp})
13278 The default socket type that Tor should use for its SOCKS socket. This must
13279 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
13280 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
13281 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
13282 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13285 If you want to customize the SOCKS socket in more detail, leave
13286 @code{socks-socket-type} at its default value of @code{'tcp} and use
13287 @code{config-file} to override the default by providing your own
13288 @code{SocksPort} option.
13292 @cindex hidden service
13293 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13294 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13295 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13298 '((22 "127.0.0.1:22")
13299 (80 "127.0.0.1:8080"))
13302 In this example, port 22 of the hidden service is mapped to local port 22, and
13303 port 80 is mapped to local port 8080.
13305 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13306 the @file{hostname} file contains the @code{.onion} host name for the hidden
13309 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13310 project's documentation} for more information.
13313 The @code{(gnu services rsync)} module provides the following services:
13315 You might want an rsync daemon if you have files that you want available
13316 so anyone (or just yourself) can download existing files or upload new
13319 @deffn {Scheme Variable} rsync-service-type
13320 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13321 The value for this service type is a
13322 @command{rsync-configuration} record as in this example:
13325 (service rsync-service-type)
13328 See below for details about @code{rsync-configuration}.
13331 @deftp {Data Type} rsync-configuration
13332 Data type representing the configuration for @code{rsync-service}.
13335 @item @code{package} (default: @var{rsync})
13336 @code{rsync} package to use.
13338 @item @code{port-number} (default: @code{873})
13339 TCP port on which @command{rsync} listens for incoming connections. If port
13340 is less than @code{1024} @command{rsync} needs to be started as the
13341 @code{root} user and group.
13343 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
13344 Name of the file where @command{rsync} writes its PID.
13346 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
13347 Name of the file where @command{rsync} writes its lock file.
13349 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
13350 Name of the file where @command{rsync} writes its log file.
13352 @item @code{use-chroot?} (default: @var{#t})
13353 Whether to use chroot for @command{rsync} shared directory.
13355 @item @code{share-path} (default: @file{/srv/rsync})
13356 Location of the @command{rsync} shared directory.
13358 @item @code{share-comment} (default: @code{"Rsync share"})
13359 Comment of the @command{rsync} shared directory.
13361 @item @code{read-only?} (default: @var{#f})
13362 Read-write permissions to shared directory.
13364 @item @code{timeout} (default: @code{300})
13365 I/O timeout in seconds.
13367 @item @code{user} (default: @var{"root"})
13368 Owner of the @code{rsync} process.
13370 @item @code{group} (default: @var{"root"})
13371 Group of the @code{rsync} process.
13373 @item @code{uid} (default: @var{"rsyncd"})
13374 User name or user ID that file transfers to and from that module should take
13375 place as when the daemon was run as @code{root}.
13377 @item @code{gid} (default: @var{"rsyncd"})
13378 Group name or group ID that will be used when accessing the module.
13383 Furthermore, @code{(gnu services ssh)} provides the following services.
13387 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
13388 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
13389 [#:allow-empty-passwords? #f] [#:root-login? #f] @
13390 [#:syslog-output? #t] [#:x11-forwarding? #t] @
13391 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
13392 [#:public-key-authentication? #t] [#:initialize? #t]
13393 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
13394 @var{host-key} must designate a file containing the host key, and readable
13397 When @var{daemonic?} is true, @command{lshd} will detach from the
13398 controlling terminal and log its output to syslogd, unless one sets
13399 @var{syslog-output?} to false. Obviously, it also makes lsh-service
13400 depend on existence of syslogd service. When @var{pid-file?} is true,
13401 @command{lshd} writes its PID to the file called @var{pid-file}.
13403 When @var{initialize?} is true, automatically create the seed and host key
13404 upon service activation if they do not exist yet. This may take long and
13405 require interaction.
13407 When @var{initialize?} is false, it is up to the user to initialize the
13408 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
13409 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
13410 basics,,, lsh, LSH Manual}).
13412 When @var{interfaces} is empty, lshd listens for connections on all the
13413 network interfaces; otherwise, @var{interfaces} must be a list of host names
13416 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
13417 passwords, and @var{root-login?} specifies whether to accept log-ins as
13420 The other options should be self-descriptive.
13425 @deffn {Scheme Variable} openssh-service-type
13426 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
13427 shell daemon, @command{sshd}. Its value must be an
13428 @code{openssh-configuration} record as in this example:
13431 (service openssh-service-type
13432 (openssh-configuration
13433 (x11-forwarding? #t)
13434 (permit-root-login 'without-password)
13436 `(("alice" ,(local-file "alice.pub"))
13437 ("bob" ,(local-file "bob.pub"))))))
13440 See below for details about @code{openssh-configuration}.
13442 This service can be extended with extra authorized keys, as in this
13446 (service-extension openssh-service-type
13447 (const `(("charlie"
13448 ,(local-file "charlie.pub")))))
13452 @deftp {Data Type} openssh-configuration
13453 This is the configuration record for OpenSSH's @command{sshd}.
13456 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
13457 Name of the file where @command{sshd} writes its PID.
13459 @item @code{port-number} (default: @code{22})
13460 TCP port on which @command{sshd} listens for incoming connections.
13462 @item @code{permit-root-login} (default: @code{#f})
13463 This field determines whether and when to allow logins as root. If
13464 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
13465 If it's the symbol @code{'without-password}, then root logins are
13466 permitted but not with password-based authentication.
13468 @item @code{allow-empty-passwords?} (default: @code{#f})
13469 When true, users with empty passwords may log in. When false, they may
13472 @item @code{password-authentication?} (default: @code{#t})
13473 When true, users may log in with their password. When false, they have
13474 other authentication methods.
13476 @item @code{public-key-authentication?} (default: @code{#t})
13477 When true, users may log in using public key authentication. When
13478 false, users have to use other authentication method.
13480 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
13481 This is used only by protocol version 2.
13483 @item @code{x11-forwarding?} (default: @code{#f})
13484 When true, forwarding of X11 graphical client connections is
13485 enabled---in other words, @command{ssh} options @option{-X} and
13486 @option{-Y} will work.
13488 @item @code{allow-agent-forwarding?} (default: @code{#t})
13489 Whether to allow agent forwarding.
13491 @item @code{allow-tcp-forwarding?} (default: @code{#t})
13492 Whether to allow TCP forwarding.
13494 @item @code{gateway-ports?} (default: @code{#f})
13495 Whether to allow gateway ports.
13497 @item @code{challenge-response-authentication?} (default: @code{#f})
13498 Specifies whether challenge response authentication is allowed (e.g.@: via
13501 @item @code{use-pam?} (default: @code{#t})
13502 Enables the Pluggable Authentication Module interface. If set to
13503 @code{#t}, this will enable PAM authentication using
13504 @code{challenge-response-authentication?} and
13505 @code{password-authentication?}, in addition to PAM account and session
13506 module processing for all authentication types.
13508 Because PAM challenge response authentication usually serves an
13509 equivalent role to password authentication, you should disable either
13510 @code{challenge-response-authentication?} or
13511 @code{password-authentication?}.
13513 @item @code{print-last-log?} (default: @code{#t})
13514 Specifies whether @command{sshd} should print the date and time of the
13515 last user login when a user logs in interactively.
13517 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
13518 Configures external subsystems (e.g.@: file transfer daemon).
13520 This is a list of two-element lists, each of which containing the
13521 subsystem name and a command (with optional arguments) to execute upon
13524 The command @command{internal-sftp} implements an in-process SFTP
13525 server. Alternately, one can specify the @command{sftp-server} command:
13527 (service openssh-service-type
13528 (openssh-configuration
13530 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
13533 @item @code{accepted-environment} (default: @code{'()})
13534 List of strings describing which environment variables may be exported.
13536 Each string gets on its own line. See the @code{AcceptEnv} option in
13537 @code{man sshd_config}.
13539 This example allows ssh-clients to export the @code{COLORTERM} variable.
13540 It is set by terminal emulators, which support colors. You can use it in
13541 your shell's ressource file to enable colors for the prompt and commands
13542 if this variable is set.
13545 (service openssh-service-type
13546 (openssh-configuration
13547 (accepted-environment '("COLORTERM"))))
13550 @item @code{authorized-keys} (default: @code{'()})
13551 @cindex authorized keys, SSH
13552 @cindex SSH authorized keys
13553 This is the list of authorized keys. Each element of the list is a user
13554 name followed by one or more file-like objects that represent SSH public
13558 (openssh-configuration
13560 `(("rekado" ,(local-file "rekado.pub"))
13561 ("chris" ,(local-file "chris.pub"))
13562 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
13566 registers the specified public keys for user accounts @code{rekado},
13567 @code{chris}, and @code{root}.
13569 Additional authorized keys can be specified @i{via}
13570 @code{service-extension}.
13572 Note that this does @emph{not} interfere with the use of
13573 @file{~/.ssh/authorized_keys}.
13575 @item @code{log-level} (default: @code{'info})
13576 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
13577 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
13578 page for @file{sshd_config} for the full list of level names.
13580 @item @code{extra-content} (default: @code{""})
13581 This field can be used to append arbitrary text to the configuration file. It
13582 is especially useful for elaborate configurations that cannot be expressed
13583 otherwise. This configuration, for example, would generally disable root
13584 logins, but permit them from one specific IP address:
13587 (openssh-configuration
13589 Match Address 192.168.0.1
13590 PermitRootLogin yes"))
13596 @deffn {Scheme Procedure} dropbear-service [@var{config}]
13597 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
13598 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
13601 For example, to specify a Dropbear service listening on port 1234, add
13602 this call to the operating system's @code{services} field:
13605 (dropbear-service (dropbear-configuration
13606 (port-number 1234)))
13610 @deftp {Data Type} dropbear-configuration
13611 This data type represents the configuration of a Dropbear SSH daemon.
13614 @item @code{dropbear} (default: @var{dropbear})
13615 The Dropbear package to use.
13617 @item @code{port-number} (default: 22)
13618 The TCP port where the daemon waits for incoming connections.
13620 @item @code{syslog-output?} (default: @code{#t})
13621 Whether to enable syslog output.
13623 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
13624 File name of the daemon's PID file.
13626 @item @code{root-login?} (default: @code{#f})
13627 Whether to allow @code{root} logins.
13629 @item @code{allow-empty-passwords?} (default: @code{#f})
13630 Whether to allow empty passwords.
13632 @item @code{password-authentication?} (default: @code{#t})
13633 Whether to enable password-based authentication.
13637 @defvr {Scheme Variable} %facebook-host-aliases
13638 This variable contains a string for use in @file{/etc/hosts}
13639 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
13640 line contains a entry that maps a known server name of the Facebook
13641 on-line service---e.g., @code{www.facebook.com}---to the local
13642 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
13644 This variable is typically used in the @code{hosts-file} field of an
13645 @code{operating-system} declaration (@pxref{operating-system Reference,
13646 @file{/etc/hosts}}):
13649 (use-modules (gnu) (guix))
13652 (host-name "mymachine")
13655 ;; Create a /etc/hosts file with aliases for "localhost"
13656 ;; and "mymachine", as well as for Facebook servers.
13657 (plain-file "hosts"
13658 (string-append (local-host-aliases host-name)
13659 %facebook-host-aliases))))
13662 This mechanism can prevent programs running locally, such as Web
13663 browsers, from accessing Facebook.
13666 The @code{(gnu services avahi)} provides the following definition.
13668 @defvr {Scheme Variable} avahi-service-type
13669 This is the service that runs @command{avahi-daemon}, a system-wide
13670 mDNS/DNS-SD responder that allows for service discovery and
13671 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
13672 Its value must be a @code{zero-configuration} record---see below.
13674 This service extends the name service cache daemon (nscd) so that it can
13675 resolve @code{.local} host names using
13676 @uref{http://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
13677 Service Switch}, for information on host name resolution.
13679 Additionally, add the @var{avahi} package to the system profile so that
13680 commands such as @command{avahi-browse} are directly usable.
13683 @deftp {Data Type} avahi-configuration
13684 Data type representation the configuration for Avahi.
13688 @item @code{host-name} (default: @code{#f})
13689 If different from @code{#f}, use that as the host name to
13690 publish for this machine; otherwise, use the machine's actual host name.
13692 @item @code{publish?} (default: @code{#t})
13693 When true, allow host names and services to be published (broadcast) over the
13696 @item @code{publish-workstation?} (default: @code{#t})
13697 When true, @command{avahi-daemon} publishes the machine's host name and IP
13698 address via mDNS on the local network. To view the host names published on
13699 your local network, you can run:
13702 avahi-browse _workstation._tcp
13705 @item @code{wide-area?} (default: @code{#f})
13706 When true, DNS-SD over unicast DNS is enabled.
13708 @item @code{ipv4?} (default: @code{#t})
13709 @itemx @code{ipv6?} (default: @code{#t})
13710 These fields determine whether to use IPv4/IPv6 sockets.
13712 @item @code{domains-to-browse} (default: @code{'()})
13713 This is a list of domains to browse.
13717 @deffn {Scheme Variable} openvswitch-service-type
13718 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
13719 service, whose value should be an @code{openvswitch-configuration}
13723 @deftp {Data Type} openvswitch-configuration
13724 Data type representing the configuration of Open vSwitch, a multilayer
13725 virtual switch which is designed to enable massive network automation
13726 through programmatic extension.
13729 @item @code{package} (default: @var{openvswitch})
13730 Package object of the Open vSwitch.
13736 @subsection X Window
13739 @cindex X Window System
13740 @cindex login manager
13741 Support for the X Window graphical display system---specifically
13742 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
13743 there is no @code{xorg-service} procedure. Instead, the X server is
13744 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
13747 @cindex GNOME, login manager
13748 GDM of course allows users to log in into window managers and desktop
13749 environments other than GNOME; for those using GNOME, GDM is required for
13750 features such as automatic screen locking.
13752 @cindex window manager
13753 To use X11, you must install at least one @dfn{window manager}---for
13754 example the @code{windowmaker} or @code{openbox} packages---preferably
13755 by adding it to the @code{packages} field of your operating system
13756 definition (@pxref{operating-system Reference, system-wide packages}).
13758 @defvr {Scheme Variable} gdm-service-type
13759 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
13760 Desktop Manager} (GDM), a program that manages graphical display servers and
13761 handles graphical user logins. Its value must be a @code{gdm-configuration}
13764 @cindex session types (X11)
13765 @cindex X11 session types
13766 GDM looks for @dfn{session types} described by the @file{.desktop} files in
13767 @file{/run/current-system/profile/share/xsessions} and allows users to choose
13768 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
13769 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
13770 set of packages automatically makes them available at the log-in screen.
13772 In addition, @file{~/.xsession} files are honored. When available,
13773 @file{~/.xsession} must be an executable that starts a window manager
13774 and/or other X clients.
13777 @deftp {Data Type} gdm-configuration
13779 @item @code{auto-login?} (default: @code{#f})
13780 @itemx @code{default-user} (default: @code{#f})
13781 When @code{auto-login?} is false, GDM presents a log-in screen.
13783 When @code{auto-login?} is true, GDM logs in directly as
13784 @code{default-user}.
13786 @item @code{gnome-shell-assets} (default: ...)
13787 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
13789 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
13790 Configuration of the Xorg graphical server.
13792 @item @code{xsession} (default: @code{(xinitrc)})
13793 Script to run before starting a X session.
13795 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
13796 File name of the @code{dbus-daemon} executable.
13798 @item @code{gdm} (default: @code{gdm})
13799 The GDM package to use.
13803 @defvr {Scheme Variable} slim-service-type
13804 This is the type for the SLiM graphical login manager for X11.
13806 Like GDM, SLiM looks for session types described by @file{.desktop} files and
13807 allows users to choose a session from the log-in screen using @kbd{F1}. It
13808 also honors @file{~/.xsession} files.
13810 Unlike GDM, SLiM does not spawn the user session on a different VT after
13811 logging in, which means that you can only start one graphical session. If you
13812 want to be able to run multiple graphical sessions at the same time you have
13813 to add multiple SLiM services to your system services. The following example
13814 shows how to replace the default GDM service with two SLiM services on tty7
13818 (use-modules (gnu services)
13819 (gnu services desktop)
13820 (gnu services xorg)
13821 (srfi srfi-1)) ;for 'remove'
13825 (services (cons* (service slim-service-type (slim-configuration
13828 (service slim-service-type (slim-configuration
13831 (remove (lambda (service)
13832 (eq? (service-kind service) gdm-service-type))
13833 %desktop-services))))
13838 @deftp {Data Type} slim-configuration
13839 Data type representing the configuration of @code{slim-service-type}.
13842 @item @code{allow-empty-passwords?} (default: @code{#t})
13843 Whether to allow logins with empty passwords.
13845 @item @code{auto-login?} (default: @code{#f})
13846 @itemx @code{default-user} (default: @code{""})
13847 When @code{auto-login?} is false, SLiM presents a log-in screen.
13849 When @code{auto-login?} is true, SLiM logs in directly as
13850 @code{default-user}.
13852 @item @code{theme} (default: @code{%default-slim-theme})
13853 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
13854 The graphical theme to use and its name.
13856 @item @code{auto-login-session} (default: @code{#f})
13857 If true, this must be the name of the executable to start as the default
13858 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
13860 If false, a session described by one of the available @file{.desktop}
13861 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
13865 You must install at least one window manager in the system profile or in
13866 your user profile. Failing to do that, if @code{auto-login-session} is
13867 false, you will be unable to log in.
13870 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13871 Configuration of the Xorg graphical server.
13873 @item @code{display} (default @code{":0"})
13874 The display on which to start the Xorg graphical server.
13876 @item @code{vt} (default @code{"vt7"})
13877 The VT on which to start the Xorg graphical server.
13879 @item @code{xauth} (default: @code{xauth})
13880 The XAuth package to use.
13882 @item @code{shepherd} (default: @code{shepherd})
13883 The Shepherd package used when invoking @command{halt} and
13886 @item @code{sessreg} (default: @code{sessreg})
13887 The sessreg package used in order to register the session.
13889 @item @code{slim} (default: @code{slim})
13890 The SLiM package to use.
13894 @defvr {Scheme Variable} %default-theme
13895 @defvrx {Scheme Variable} %default-theme-name
13896 The default SLiM theme and its name.
13900 @deftp {Data Type} sddm-configuration
13901 This is the data type representing the sddm service configuration.
13904 @item @code{display-server} (default: "x11")
13905 Select display server to use for the greeter. Valid values are "x11"
13908 @item @code{numlock} (default: "on")
13909 Valid values are "on", "off" or "none".
13911 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
13912 Command to run when halting.
13914 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
13915 Command to run when rebooting.
13917 @item @code{theme} (default "maldives")
13918 Theme to use. Default themes provided by SDDM are "elarun" or "maldives".
13920 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
13921 Directory to look for themes.
13923 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
13924 Directory to look for faces.
13926 @item @code{default-path} (default "/run/current-system/profile/bin")
13927 Default PATH to use.
13929 @item @code{minimum-uid} (default: 1000)
13930 Minimum UID displayed in SDDM and allowed for log-in.
13932 @item @code{maximum-uid} (default: 2000)
13933 Maximum UID to display in SDDM.
13935 @item @code{remember-last-user?} (default #t)
13936 Remember last user.
13938 @item @code{remember-last-session?} (default #t)
13939 Remember last session.
13941 @item @code{hide-users} (default "")
13942 Usernames to hide from SDDM greeter.
13944 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
13945 Users with shells listed will be hidden from the SDDM greeter.
13947 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
13948 Script to run before starting a wayland session.
13950 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
13951 Directory to look for desktop files starting wayland sessions.
13953 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13954 Configuration of the Xorg graphical server.
13956 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
13959 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
13962 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
13963 Script to run after starting xorg-server.
13965 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
13966 Script to run before stopping xorg-server.
13968 @item @code{xsession-command} (default: @code{xinitrc})
13969 Script to run before starting a X session.
13971 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
13972 Directory to look for desktop files starting X sessions.
13974 @item @code{minimum-vt} (default: 7)
13977 @item @code{auto-login-user} (default "")
13978 User to use for auto-login.
13980 @item @code{auto-login-session} (default "")
13981 Desktop file to use for auto-login.
13983 @item @code{relogin?} (default #f)
13984 Relogin after logout.
13989 @cindex login manager
13991 @deffn {Scheme Procedure} sddm-service config
13992 Return a service that spawns the SDDM graphical login manager for config of
13993 type @code{<sddm-configuration>}.
13996 (sddm-service (sddm-configuration
13997 (auto-login-user "Alice")
13998 (auto-login-session "xfce.desktop")))
14002 @cindex Xorg, configuration
14003 @deftp {Data Type} xorg-configuration
14004 This data type represents the configuration of the Xorg graphical display
14005 server. Note that there is not Xorg service; instead, the X server is started
14006 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
14007 of these display managers aggregates an @code{xorg-configuration} record.
14010 @item @code{modules} (default: @code{%default-xorg-modules})
14011 This is a list of @dfn{module packages} loaded by the Xorg
14012 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
14014 @item @code{fonts} (default: @code{%default-xorg-fonts})
14015 This is a list of font directories to add to the server's @dfn{font path}.
14017 @item @code{drivers} (default: @code{'()})
14018 This must be either the empty list, in which case Xorg chooses a graphics
14019 driver automatically, or a list of driver names that will be tried in this
14020 order---e.g., @code{("modesetting" "vesa")}.
14022 @item @code{resolutions} (default: @code{'()})
14023 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
14024 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
14027 @cindex keyboard layout, for Xorg
14028 @cindex keymap, for Xorg
14029 @item @code{keyboard-layout} (default: @code{#f})
14030 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
14031 English (``qwerty'') for a 105-key PC keyboard.
14033 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
14034 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
14035 information on how to specify the keyboard layout.
14037 @item @code{extra-config} (default: @code{'()})
14038 This is a list of strings or objects appended to the configuration file. It
14039 is used to pass extra text to be added verbatim to the configuration file.
14041 @item @code{server} (default: @code{xorg-server})
14042 This is the package providing the Xorg server.
14044 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
14045 This is the list of command-line arguments to pass to the X server. The
14046 default is @code{-nolisten tcp}.
14050 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
14051 [@var{login-manager-service-type}]
14052 Tell the log-in manager (of type @var{login-manager-service-type}) to use
14053 @var{config}, an @code{<xorg-configuration>} record.
14055 Since the Xorg configuration is embedded in the log-in manager's
14056 configuration---e.g., @code{gdm-configuration}---this procedure provides a
14057 shorthand to set the Xorg configuration.
14060 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
14061 Return a @code{startx} script in which the modules, fonts, etc. specified
14062 in @var{config}, are available. The result should be used in place of
14065 Usually the X server is started by a login manager.
14069 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
14070 Add @var{package}, a package for a screen locker or screen saver whose
14071 command is @var{program}, to the set of setuid programs and add a PAM entry
14072 for it. For example:
14075 (screen-locker-service xlockmore "xlock")
14078 makes the good ol' XlockMore usable.
14082 @node Printing Services
14083 @subsection Printing Services
14085 @cindex printer support with CUPS
14086 The @code{(gnu services cups)} module provides a Guix service definition
14087 for the CUPS printing service. To add printer support to a Guix
14088 system, add a @code{cups-service} to the operating system definition:
14090 @deffn {Scheme Variable} cups-service-type
14091 The service type for the CUPS print server. Its value should be a valid
14092 CUPS configuration (see below). To use the default settings, simply
14095 (service cups-service-type)
14099 The CUPS configuration controls the basic things about your CUPS
14100 installation: what interfaces it listens on, what to do if a print job
14101 fails, how much logging to do, and so on. To actually add a printer,
14102 you have to visit the @url{http://localhost:631} URL, or use a tool such
14103 as GNOME's printer configuration services. By default, configuring a
14104 CUPS service will generate a self-signed certificate if needed, for
14105 secure connections to the print server.
14107 Suppose you want to enable the Web interface of CUPS and also add
14108 support for Epson printers @i{via} the @code{escpr} package and for HP
14109 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
14110 like this (you need to use the @code{(gnu packages cups)} module):
14113 (service cups-service-type
14114 (cups-configuration
14115 (web-interface? #t)
14117 (list cups-filters escpr hplip-minimal))))
14120 Note: If you wish to use the Qt5 based GUI which comes with the hplip
14121 package then it is suggested that you install the @code{hplip} package,
14122 either in your OS configuration file or as your user.
14124 The available configuration parameters follow. Each parameter
14125 definition is preceded by its type; for example, @samp{string-list foo}
14126 indicates that the @code{foo} parameter should be specified as a list of
14127 strings. There is also a way to specify the configuration as a string,
14128 if you have an old @code{cupsd.conf} file that you want to port over
14129 from some other system; see the end for more details.
14131 @c The following documentation was initially generated by
14132 @c (generate-documentation) in (gnu services cups). Manually maintained
14133 @c documentation is better, so we shouldn't hesitate to edit below as
14134 @c needed. However if the change you want to make to this documentation
14135 @c can be done in an automated way, it's probably easier to change
14136 @c (generate-documentation) than to make it below and have to deal with
14137 @c the churn as CUPS updates.
14140 Available @code{cups-configuration} fields are:
14142 @deftypevr {@code{cups-configuration} parameter} package cups
14146 @deftypevr {@code{cups-configuration} parameter} package-list extensions
14147 Drivers and other extensions to the CUPS package.
14150 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
14151 Configuration of where to write logs, what directories to use for print
14152 spools, and related privileged configuration parameters.
14154 Available @code{files-configuration} fields are:
14156 @deftypevr {@code{files-configuration} parameter} log-location access-log
14157 Defines the access log filename. Specifying a blank filename disables
14158 access log generation. The value @code{stderr} causes log entries to be
14159 sent to the standard error file when the scheduler is running in the
14160 foreground, or to the system log daemon when run in the background. The
14161 value @code{syslog} causes log entries to be sent to the system log
14162 daemon. The server name may be included in filenames using the string
14163 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
14165 Defaults to @samp{"/var/log/cups/access_log"}.
14168 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
14169 Where CUPS should cache data.
14171 Defaults to @samp{"/var/cache/cups"}.
14174 @deftypevr {@code{files-configuration} parameter} string config-file-perm
14175 Specifies the permissions for all configuration files that the scheduler
14178 Note that the permissions for the printers.conf file are currently
14179 masked to only allow access from the scheduler user (typically root).
14180 This is done because printer device URIs sometimes contain sensitive
14181 authentication information that should not be generally known on the
14182 system. There is no way to disable this security feature.
14184 Defaults to @samp{"0640"}.
14187 @deftypevr {@code{files-configuration} parameter} log-location error-log
14188 Defines the error log filename. Specifying a blank filename disables
14189 error log generation. The value @code{stderr} causes log entries to be
14190 sent to the standard error file when the scheduler is running in the
14191 foreground, or to the system log daemon when run in the background. The
14192 value @code{syslog} causes log entries to be sent to the system log
14193 daemon. The server name may be included in filenames using the string
14194 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
14196 Defaults to @samp{"/var/log/cups/error_log"}.
14199 @deftypevr {@code{files-configuration} parameter} string fatal-errors
14200 Specifies which errors are fatal, causing the scheduler to exit. The
14205 No errors are fatal.
14208 All of the errors below are fatal.
14211 Browsing initialization errors are fatal, for example failed connections
14212 to the DNS-SD daemon.
14215 Configuration file syntax errors are fatal.
14218 Listen or Port errors are fatal, except for IPv6 failures on the
14219 loopback or @code{any} addresses.
14222 Log file creation or write errors are fatal.
14225 Bad startup file permissions are fatal, for example shared TLS
14226 certificate and key files with world-read permissions.
14229 Defaults to @samp{"all -browse"}.
14232 @deftypevr {@code{files-configuration} parameter} boolean file-device?
14233 Specifies whether the file pseudo-device can be used for new printer
14234 queues. The URI @uref{file:///dev/null} is always allowed.
14236 Defaults to @samp{#f}.
14239 @deftypevr {@code{files-configuration} parameter} string group
14240 Specifies the group name or ID that will be used when executing external
14243 Defaults to @samp{"lp"}.
14246 @deftypevr {@code{files-configuration} parameter} string log-file-perm
14247 Specifies the permissions for all log files that the scheduler writes.
14249 Defaults to @samp{"0644"}.
14252 @deftypevr {@code{files-configuration} parameter} log-location page-log
14253 Defines the page log filename. Specifying a blank filename disables
14254 page log generation. The value @code{stderr} causes log entries to be
14255 sent to the standard error file when the scheduler is running in the
14256 foreground, or to the system log daemon when run in the background. The
14257 value @code{syslog} causes log entries to be sent to the system log
14258 daemon. The server name may be included in filenames using the string
14259 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
14261 Defaults to @samp{"/var/log/cups/page_log"}.
14264 @deftypevr {@code{files-configuration} parameter} string remote-root
14265 Specifies the username that is associated with unauthenticated accesses
14266 by clients claiming to be the root user. The default is @code{remroot}.
14268 Defaults to @samp{"remroot"}.
14271 @deftypevr {@code{files-configuration} parameter} file-name request-root
14272 Specifies the directory that contains print jobs and other HTTP request
14275 Defaults to @samp{"/var/spool/cups"}.
14278 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
14279 Specifies the level of security sandboxing that is applied to print
14280 filters, backends, and other child processes of the scheduler; either
14281 @code{relaxed} or @code{strict}. This directive is currently only
14282 used/supported on macOS.
14284 Defaults to @samp{strict}.
14287 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
14288 Specifies the location of TLS certificates and private keys. CUPS will
14289 look for public and private keys in this directory: a @code{.crt} files
14290 for PEM-encoded certificates and corresponding @code{.key} files for
14291 PEM-encoded private keys.
14293 Defaults to @samp{"/etc/cups/ssl"}.
14296 @deftypevr {@code{files-configuration} parameter} file-name server-root
14297 Specifies the directory containing the server configuration files.
14299 Defaults to @samp{"/etc/cups"}.
14302 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
14303 Specifies whether the scheduler calls fsync(2) after writing
14304 configuration or state files.
14306 Defaults to @samp{#f}.
14309 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
14310 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
14313 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
14314 Specifies the directory where temporary files are stored.
14316 Defaults to @samp{"/var/spool/cups/tmp"}.
14319 @deftypevr {@code{files-configuration} parameter} string user
14320 Specifies the user name or ID that is used when running external
14323 Defaults to @samp{"lp"}.
14326 @deftypevr {@code{files-configuration} parameter} string set-env
14327 Set the specified environment variable to be passed to child processes.
14329 Defaults to @samp{"variable value"}.
14333 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
14334 Specifies the logging level for the AccessLog file. The @code{config}
14335 level logs when printers and classes are added, deleted, or modified and
14336 when configuration files are accessed or updated. The @code{actions}
14337 level logs when print jobs are submitted, held, released, modified, or
14338 canceled, and any of the conditions for @code{config}. The @code{all}
14339 level logs all requests.
14341 Defaults to @samp{actions}.
14344 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
14345 Specifies whether to purge job history data automatically when it is no
14346 longer required for quotas.
14348 Defaults to @samp{#f}.
14351 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
14352 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
14353 For example, @samp{"_cups" "_print"} will tell network clients that both
14354 CUPS sharing and IPP Everywhere are supported.
14356 Defaults to @samp{"_cups"}.
14359 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
14360 Specifies which protocols to use for local printer sharing.
14362 Defaults to @samp{dnssd}.
14365 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
14366 Specifies whether the CUPS web interface is advertised.
14368 Defaults to @samp{#f}.
14371 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
14372 Specifies whether shared printers are advertised.
14374 Defaults to @samp{#f}.
14377 @deftypevr {@code{cups-configuration} parameter} string classification
14378 Specifies the security classification of the server. Any valid banner
14379 name can be used, including "classified", "confidential", "secret",
14380 "topsecret", and "unclassified", or the banner can be omitted to disable
14381 secure printing functions.
14383 Defaults to @samp{""}.
14386 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
14387 Specifies whether users may override the classification (cover page) of
14388 individual print jobs using the @code{job-sheets} option.
14390 Defaults to @samp{#f}.
14393 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
14394 Specifies the default type of authentication to use.
14396 Defaults to @samp{Basic}.
14399 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
14400 Specifies whether encryption will be used for authenticated requests.
14402 Defaults to @samp{Required}.
14405 @deftypevr {@code{cups-configuration} parameter} string default-language
14406 Specifies the default language to use for text and web content.
14408 Defaults to @samp{"en"}.
14411 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
14412 Specifies the default paper size for new print queues. @samp{"Auto"}
14413 uses a locale-specific default, while @samp{"None"} specifies there is
14414 no default paper size. Specific size names are typically
14415 @samp{"Letter"} or @samp{"A4"}.
14417 Defaults to @samp{"Auto"}.
14420 @deftypevr {@code{cups-configuration} parameter} string default-policy
14421 Specifies the default access policy to use.
14423 Defaults to @samp{"default"}.
14426 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
14427 Specifies whether local printers are shared by default.
14429 Defaults to @samp{#t}.
14432 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
14433 Specifies the delay for updating of configuration and state files, in
14434 seconds. A value of 0 causes the update to happen as soon as possible,
14435 typically within a few milliseconds.
14437 Defaults to @samp{30}.
14440 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
14441 Specifies what to do when an error occurs. Possible values are
14442 @code{abort-job}, which will discard the failed print job;
14443 @code{retry-job}, which will retry the job at a later time;
14444 @code{retry-current-job}, which retries the failed job immediately; and
14445 @code{stop-printer}, which stops the printer.
14447 Defaults to @samp{stop-printer}.
14450 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
14451 Specifies the maximum cost of filters that are run concurrently, which
14452 can be used to minimize disk, memory, and CPU resource problems. A
14453 limit of 0 disables filter limiting. An average print to a
14454 non-PostScript printer needs a filter limit of about 200. A PostScript
14455 printer needs about half that (100). Setting the limit below these
14456 thresholds will effectively limit the scheduler to printing a single job
14459 Defaults to @samp{0}.
14462 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
14463 Specifies the scheduling priority of filters that are run to print a
14464 job. The nice value ranges from 0, the highest priority, to 19, the
14467 Defaults to @samp{0}.
14470 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
14471 Specifies whether to do reverse lookups on connecting clients. The
14472 @code{double} setting causes @code{cupsd} to verify that the hostname
14473 resolved from the address matches one of the addresses returned for that
14474 hostname. Double lookups also prevent clients with unregistered
14475 addresses from connecting to your server. Only set this option to
14476 @code{#t} or @code{double} if absolutely required.
14478 Defaults to @samp{#f}.
14481 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
14482 Specifies the number of seconds to wait before killing the filters and
14483 backend associated with a canceled or held job.
14485 Defaults to @samp{30}.
14488 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
14489 Specifies the interval between retries of jobs in seconds. This is
14490 typically used for fax queues but can also be used with normal print
14491 queues whose error policy is @code{retry-job} or
14492 @code{retry-current-job}.
14494 Defaults to @samp{30}.
14497 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
14498 Specifies the number of retries that are done for jobs. This is
14499 typically used for fax queues but can also be used with normal print
14500 queues whose error policy is @code{retry-job} or
14501 @code{retry-current-job}.
14503 Defaults to @samp{5}.
14506 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
14507 Specifies whether to support HTTP keep-alive connections.
14509 Defaults to @samp{#t}.
14512 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
14513 Specifies how long an idle client connection remains open, in seconds.
14515 Defaults to @samp{30}.
14518 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
14519 Specifies the maximum size of print files, IPP requests, and HTML form
14520 data. A limit of 0 disables the limit check.
14522 Defaults to @samp{0}.
14525 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
14526 Listens on the specified interfaces for connections. Valid values are
14527 of the form @var{address}:@var{port}, where @var{address} is either an
14528 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
14529 indicate all addresses. Values can also be file names of local UNIX
14530 domain sockets. The Listen directive is similar to the Port directive
14531 but allows you to restrict access to specific interfaces or networks.
14534 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
14535 Specifies the number of pending connections that will be allowed. This
14536 normally only affects very busy servers that have reached the MaxClients
14537 limit, but can also be triggered by large numbers of simultaneous
14538 connections. When the limit is reached, the operating system will
14539 refuse additional connections until the scheduler can accept the pending
14542 Defaults to @samp{128}.
14545 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
14546 Specifies a set of additional access controls.
14548 Available @code{location-access-controls} fields are:
14550 @deftypevr {@code{location-access-controls} parameter} file-name path
14551 Specifies the URI path to which the access control applies.
14554 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
14555 Access controls for all access to this path, in the same format as the
14556 @code{access-controls} of @code{operation-access-control}.
14558 Defaults to @samp{()}.
14561 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
14562 Access controls for method-specific access to this path.
14564 Defaults to @samp{()}.
14566 Available @code{method-access-controls} fields are:
14568 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
14569 If @code{#t}, apply access controls to all methods except the listed
14570 methods. Otherwise apply to only the listed methods.
14572 Defaults to @samp{#f}.
14575 @deftypevr {@code{method-access-controls} parameter} method-list methods
14576 Methods to which this access control applies.
14578 Defaults to @samp{()}.
14581 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
14582 Access control directives, as a list of strings. Each string should be
14583 one directive, such as "Order allow,deny".
14585 Defaults to @samp{()}.
14590 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
14591 Specifies the number of debugging messages that are retained for logging
14592 if an error occurs in a print job. Debug messages are logged regardless
14593 of the LogLevel setting.
14595 Defaults to @samp{100}.
14598 @deftypevr {@code{cups-configuration} parameter} log-level log-level
14599 Specifies the level of logging for the ErrorLog file. The value
14600 @code{none} stops all logging while @code{debug2} logs everything.
14602 Defaults to @samp{info}.
14605 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
14606 Specifies the format of the date and time in the log files. The value
14607 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
14609 Defaults to @samp{standard}.
14612 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
14613 Specifies the maximum number of simultaneous clients that are allowed by
14616 Defaults to @samp{100}.
14619 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
14620 Specifies the maximum number of simultaneous clients that are allowed
14621 from a single address.
14623 Defaults to @samp{100}.
14626 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
14627 Specifies the maximum number of copies that a user can print of each
14630 Defaults to @samp{9999}.
14633 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
14634 Specifies the maximum time a job may remain in the @code{indefinite}
14635 hold state before it is canceled. A value of 0 disables cancellation of
14638 Defaults to @samp{0}.
14641 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
14642 Specifies the maximum number of simultaneous jobs that are allowed. Set
14643 to 0 to allow an unlimited number of jobs.
14645 Defaults to @samp{500}.
14648 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
14649 Specifies the maximum number of simultaneous jobs that are allowed per
14650 printer. A value of 0 allows up to MaxJobs jobs per printer.
14652 Defaults to @samp{0}.
14655 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
14656 Specifies the maximum number of simultaneous jobs that are allowed per
14657 user. A value of 0 allows up to MaxJobs jobs per user.
14659 Defaults to @samp{0}.
14662 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
14663 Specifies the maximum time a job may take to print before it is
14664 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
14666 Defaults to @samp{10800}.
14669 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
14670 Specifies the maximum size of the log files before they are rotated, in
14671 bytes. The value 0 disables log rotation.
14673 Defaults to @samp{1048576}.
14676 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
14677 Specifies the maximum amount of time to allow between files in a
14678 multiple file print job, in seconds.
14680 Defaults to @samp{300}.
14683 @deftypevr {@code{cups-configuration} parameter} string page-log-format
14684 Specifies the format of PageLog lines. Sequences beginning with percent
14685 (@samp{%}) characters are replaced with the corresponding information,
14686 while all other characters are copied literally. The following percent
14687 sequences are recognized:
14691 insert a single percent character
14694 insert the value of the specified IPP attribute
14697 insert the number of copies for the current page
14700 insert the current page number
14703 insert the current date and time in common log format
14709 insert the printer name
14712 insert the username
14715 A value of the empty string disables page logging. The string @code{%p
14716 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
14717 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
14720 Defaults to @samp{""}.
14723 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
14724 Passes the specified environment variable(s) to child processes; a list
14727 Defaults to @samp{()}.
14730 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
14731 Specifies named access control policies.
14733 Available @code{policy-configuration} fields are:
14735 @deftypevr {@code{policy-configuration} parameter} string name
14736 Name of the policy.
14739 @deftypevr {@code{policy-configuration} parameter} string job-private-access
14740 Specifies an access list for a job's private values. @code{@@ACL} maps
14741 to the printer's requesting-user-name-allowed or
14742 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14743 owner. @code{@@SYSTEM} maps to the groups listed for the
14744 @code{system-group} field of the @code{files-config} configuration,
14745 which is reified into the @code{cups-files.conf(5)} file. Other
14746 possible elements of the access list include specific user names, and
14747 @code{@@@var{group}} to indicate members of a specific group. The
14748 access list may also be simply @code{all} or @code{default}.
14750 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14753 @deftypevr {@code{policy-configuration} parameter} string job-private-values
14754 Specifies the list of job values to make private, or @code{all},
14755 @code{default}, or @code{none}.
14757 Defaults to @samp{"job-name job-originating-host-name
14758 job-originating-user-name phone"}.
14761 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
14762 Specifies an access list for a subscription's private values.
14763 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
14764 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14765 owner. @code{@@SYSTEM} maps to the groups listed for the
14766 @code{system-group} field of the @code{files-config} configuration,
14767 which is reified into the @code{cups-files.conf(5)} file. Other
14768 possible elements of the access list include specific user names, and
14769 @code{@@@var{group}} to indicate members of a specific group. The
14770 access list may also be simply @code{all} or @code{default}.
14772 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14775 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
14776 Specifies the list of job values to make private, or @code{all},
14777 @code{default}, or @code{none}.
14779 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
14780 notify-subscriber-user-name notify-user-data"}.
14783 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
14784 Access control by IPP operation.
14786 Defaults to @samp{()}.
14790 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
14791 Specifies whether job files (documents) are preserved after a job is
14792 printed. If a numeric value is specified, job files are preserved for
14793 the indicated number of seconds after printing. Otherwise a boolean
14794 value applies indefinitely.
14796 Defaults to @samp{86400}.
14799 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
14800 Specifies whether the job history is preserved after a job is printed.
14801 If a numeric value is specified, the job history is preserved for the
14802 indicated number of seconds after printing. If @code{#t}, the job
14803 history is preserved until the MaxJobs limit is reached.
14805 Defaults to @samp{#t}.
14808 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
14809 Specifies the amount of time to wait for job completion before
14810 restarting the scheduler.
14812 Defaults to @samp{30}.
14815 @deftypevr {@code{cups-configuration} parameter} string rip-cache
14816 Specifies the maximum amount of memory to use when converting documents
14817 into bitmaps for a printer.
14819 Defaults to @samp{"128m"}.
14822 @deftypevr {@code{cups-configuration} parameter} string server-admin
14823 Specifies the email address of the server administrator.
14825 Defaults to @samp{"root@@localhost.localdomain"}.
14828 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
14829 The ServerAlias directive is used for HTTP Host header validation when
14830 clients connect to the scheduler from external interfaces. Using the
14831 special name @code{*} can expose your system to known browser-based DNS
14832 rebinding attacks, even when accessing sites through a firewall. If the
14833 auto-discovery of alternate names does not work, we recommend listing
14834 each alternate name with a ServerAlias directive instead of using
14837 Defaults to @samp{*}.
14840 @deftypevr {@code{cups-configuration} parameter} string server-name
14841 Specifies the fully-qualified host name of the server.
14843 Defaults to @samp{"localhost"}.
14846 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
14847 Specifies what information is included in the Server header of HTTP
14848 responses. @code{None} disables the Server header. @code{ProductOnly}
14849 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
14850 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
14851 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
14852 the output of the @code{uname} command. @code{Full} reports @code{CUPS
14853 2.0.0 (@var{uname}) IPP/2.0}.
14855 Defaults to @samp{Minimal}.
14858 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
14859 Listens on the specified interfaces for encrypted connections. Valid
14860 values are of the form @var{address}:@var{port}, where @var{address} is
14861 either an IPv6 address enclosed in brackets, an IPv4 address, or
14862 @code{*} to indicate all addresses.
14864 Defaults to @samp{()}.
14867 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
14868 Sets encryption options. By default, CUPS only supports encryption
14869 using TLS v1.0 or higher using known secure cipher suites. Security is
14870 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
14871 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
14872 suites, which are required for some older clients. The @code{AllowSSL3} option
14873 enables SSL v3.0, which is required for some older clients that do not support
14874 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
14875 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
14876 protocol version to TLS v1.1.
14878 Defaults to @samp{()}.
14881 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
14882 Specifies whether the scheduler requires clients to strictly adhere to
14883 the IPP specifications.
14885 Defaults to @samp{#f}.
14888 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
14889 Specifies the HTTP request timeout, in seconds.
14891 Defaults to @samp{300}.
14895 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
14896 Specifies whether the web interface is enabled.
14898 Defaults to @samp{#f}.
14901 At this point you're probably thinking ``oh dear, Guix manual, I like
14902 you but you can stop already with the configuration options''. Indeed.
14903 However, one more point: it could be that you have an existing
14904 @code{cupsd.conf} that you want to use. In that case, you can pass an
14905 @code{opaque-cups-configuration} as the configuration of a
14906 @code{cups-service-type}.
14908 Available @code{opaque-cups-configuration} fields are:
14910 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
14914 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
14915 The contents of the @code{cupsd.conf}, as a string.
14918 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
14919 The contents of the @code{cups-files.conf} file, as a string.
14922 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
14923 strings of the same name, you could instantiate a CUPS service like
14927 (service cups-service-type
14928 (opaque-cups-configuration
14929 (cupsd.conf cupsd.conf)
14930 (cups-files.conf cups-files.conf)))
14934 @node Desktop Services
14935 @subsection Desktop Services
14937 The @code{(gnu services desktop)} module provides services that are
14938 usually useful in the context of a ``desktop'' setup---that is, on a
14939 machine running a graphical display server, possibly with graphical user
14940 interfaces, etc. It also defines services that provide specific desktop
14941 environments like GNOME, Xfce or MATE.
14943 To simplify things, the module defines a variable containing the set of
14944 services that users typically expect on a machine with a graphical
14945 environment and networking:
14947 @defvr {Scheme Variable} %desktop-services
14948 This is a list of services that builds upon @code{%base-services} and
14949 adds or adjusts services for a typical ``desktop'' setup.
14951 In particular, it adds a graphical login manager (@pxref{X Window,
14952 @code{gdm-service-type}}), screen lockers, a network management tool
14953 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
14954 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
14955 energy and color management services, the @code{elogind} login and seat
14956 manager, the Polkit privilege service, the GeoClue location service, the
14957 AccountsService daemon that allows authorized users change system passwords,
14958 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
14959 name service switch service configured to be able to use @code{nss-mdns}
14960 (@pxref{Name Service Switch, mDNS}).
14963 The @code{%desktop-services} variable can be used as the @code{services}
14964 field of an @code{operating-system} declaration (@pxref{operating-system
14965 Reference, @code{services}}).
14967 Additionally, the @code{gnome-desktop-service-type},
14968 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
14969 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
14970 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
14971 services like the backlight adjustment helpers and the power management
14972 utilities are added to the system, extending @code{polkit} and @code{dbus}
14973 appropriately, allowing GNOME to operate with elevated privileges on a
14974 limited number of special-purpose system interfaces. Additionally,
14975 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
14976 metapackage to the system profile. Likewise, adding the Xfce service
14977 not only adds the @code{xfce} metapackage to the system profile, but it
14978 also gives the Thunar file manager the ability to open a ``root-mode''
14979 file management window, if the user authenticates using the
14980 administrator's password via the standard polkit graphical interface.
14981 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
14982 appropriately, allowing MATE to operate with elevated privileges on a
14983 limited number of special-purpose system interfaces. Additionally,
14984 adding a service of type @code{mate-desktop-service-type} adds the MATE
14985 metapackage to the system profile. ``Adding Enlightenment'' means that
14986 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
14987 are set as setuid, allowing Enlightenment's screen locker and other
14988 functionality to work as expetected.
14990 The desktop environments in Guix use the Xorg display server by
14991 default. If you'd like to use the newer display server protocol
14992 called Wayland, you need to use the @code{sddm-service} instead of
14993 GDM as the graphical login manager. You should then
14994 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
14995 also try starting GNOME on Wayland manually from a TTY with the
14996 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
14997 gnome-session``. Currently only GNOME has support for Wayland.
14999 @defvr {Scheme Variable} gnome-desktop-service-type
15000 This is the type of the service that adds the @uref{https://www.gnome.org,
15001 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
15002 object (see below.)
15004 This service adds the @code{gnome} package to the system profile, and extends
15005 polkit with the actions from @code{gnome-settings-daemon}.
15008 @deftp {Data Type} gnome-desktop-configuration
15009 Configuration record for the GNOME desktop environment.
15012 @item @code{gnome} (default: @code{gnome})
15013 The GNOME package to use.
15017 @defvr {Scheme Variable} xfce-desktop-service-type
15018 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
15019 desktop environment. Its value is an @code{xfce-desktop-configuration} object
15022 This service adds the @code{xfce} package to the system profile, and
15023 extends polkit with the ability for @code{thunar} to manipulate the file
15024 system as root from within a user session, after the user has authenticated
15025 with the administrator's password.
15028 @deftp {Data Type} xfce-desktop-configuration
15029 Configuration record for the Xfce desktop environment.
15032 @item @code{xfce} (default: @code{xfce})
15033 The Xfce package to use.
15037 @deffn {Scheme Variable} mate-desktop-service-type
15038 This is the type of the service that runs the @uref{https://mate-desktop.org/,
15039 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
15040 object (see below.)
15042 This service adds the @code{mate} package to the system
15043 profile, and extends polkit with the actions from
15044 @code{mate-settings-daemon}.
15047 @deftp {Data Type} mate-desktop-configuration
15048 Configuration record for the MATE desktop environment.
15051 @item @code{mate} (default: @code{mate})
15052 The MATE package to use.
15056 @deffn {Scheme Variable} enlightenment-desktop-service-type
15057 Return a service that adds the @code{enlightenment} package to the system
15058 profile, and extends dbus with actions from @code{efl}.
15061 @deftp {Data Type} enlightenment-desktop-service-configuration
15063 @item @code{enlightenment} (default: @code{enlightenment})
15064 The enlightenment package to use.
15068 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
15069 the default @code{%desktop-services} variable doesn't include any of
15070 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
15071 @code{%desktop-services} in the @code{services} field of your
15072 @code{operating-system}:
15075 (use-modules (gnu))
15076 (use-service-modules desktop)
15079 ;; cons* adds items to the list given as its last argument.
15080 (services (cons* (service gnome-desktop-service-type)
15081 (service xfce-desktop-service)
15082 %desktop-services))
15086 These desktop environments will then be available as options in the
15087 graphical login window.
15089 The actual service definitions included in @code{%desktop-services} and
15090 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
15091 are described below.
15093 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
15094 Return a service that runs the ``system bus'', using @var{dbus}, with
15095 support for @var{services}.
15097 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
15098 facility. Its system bus is used to allow system services to communicate
15099 and to be notified of system-wide events.
15101 @var{services} must be a list of packages that provide an
15102 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
15103 and policy files. For example, to allow avahi-daemon to use the system bus,
15104 @var{services} must be equal to @code{(list avahi)}.
15107 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
15108 Return a service that runs the @code{elogind} login and
15109 seat management daemon. @uref{https://github.com/elogind/elogind,
15110 Elogind} exposes a D-Bus interface that can be used to know which users
15111 are logged in, know what kind of sessions they have open, suspend the
15112 system, inhibit system suspend, reboot the system, and other tasks.
15114 Elogind handles most system-level power events for a computer, for
15115 example suspending the system when a lid is closed, or shutting it down
15116 when the power button is pressed.
15118 The @var{config} keyword argument specifies the configuration for
15119 elogind, and should be the result of an @code{(elogind-configuration
15120 (@var{parameter} @var{value})...)} invocation. Available parameters and
15121 their default values are:
15124 @item kill-user-processes?
15126 @item kill-only-users
15128 @item kill-exclude-users
15130 @item inhibit-delay-max-seconds
15132 @item handle-power-key
15134 @item handle-suspend-key
15136 @item handle-hibernate-key
15138 @item handle-lid-switch
15140 @item handle-lid-switch-docked
15142 @item power-key-ignore-inhibited?
15144 @item suspend-key-ignore-inhibited?
15146 @item hibernate-key-ignore-inhibited?
15148 @item lid-switch-ignore-inhibited?
15150 @item holdoff-timeout-seconds
15154 @item idle-action-seconds
15156 @item runtime-directory-size-percent
15158 @item runtime-directory-size
15162 @item suspend-state
15163 @code{("mem" "standby" "freeze")}
15166 @item hibernate-state
15168 @item hibernate-mode
15169 @code{("platform" "shutdown")}
15170 @item hybrid-sleep-state
15172 @item hybrid-sleep-mode
15173 @code{("suspend" "platform" "shutdown")}
15177 @deffn {Scheme Procedure} accountsservice-service @
15178 [#:accountsservice @var{accountsservice}]
15179 Return a service that runs AccountsService, a system service that can
15180 list available accounts, change their passwords, and so on.
15181 AccountsService integrates with PolicyKit to enable unprivileged users
15182 to acquire the capability to modify their system configuration.
15183 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
15184 accountsservice web site} for more information.
15186 The @var{accountsservice} keyword argument is the @code{accountsservice}
15187 package to expose as a service.
15190 @deffn {Scheme Procedure} polkit-service @
15191 [#:polkit @var{polkit}]
15192 Return a service that runs the
15193 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
15194 management service}, which allows system administrators to grant access to
15195 privileged operations in a structured way. By querying the Polkit service, a
15196 privileged system component can know when it should grant additional
15197 capabilities to ordinary users. For example, an ordinary user can be granted
15198 the capability to suspend the system if the user is logged in locally.
15201 @defvr {Scheme Variable} upower-service-type
15202 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
15203 system-wide monitor for power consumption and battery levels, with the given
15204 configuration settings.
15206 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
15207 notably used by GNOME.
15210 @deftp {Data Type} upower-configuration
15211 Data type representation the configuration for UPower.
15215 @item @code{upower} (default: @var{upower})
15216 Package to use for @code{upower}.
15218 @item @code{watts-up-pro?} (default: @code{#f})
15219 Enable the Watts Up Pro device.
15221 @item @code{poll-batteries?} (default: @code{#t})
15222 Enable polling the kernel for battery level changes.
15224 @item @code{ignore-lid?} (default: @code{#f})
15225 Ignore the lid state, this can be useful if it's incorrect on a device.
15227 @item @code{use-percentage-for-policy?} (default: @code{#f})
15228 Whether battery percentage based policy should be used. The default is to use
15229 the time left, change to @code{#t} to use the percentage.
15231 @item @code{percentage-low} (default: @code{10})
15232 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15233 at which the battery is considered low.
15235 @item @code{percentage-critical} (default: @code{3})
15236 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15237 at which the battery is considered critical.
15239 @item @code{percentage-action} (default: @code{2})
15240 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15241 at which action will be taken.
15243 @item @code{time-low} (default: @code{1200})
15244 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15245 seconds at which the battery is considered low.
15247 @item @code{time-critical} (default: @code{300})
15248 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15249 seconds at which the battery is considered critical.
15251 @item @code{time-action} (default: @code{120})
15252 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15253 seconds at which action will be taken.
15255 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
15256 The action taken when @code{percentage-action} or @code{time-action} is
15257 reached (depending on the configuration of @code{use-percentage-for-policy?}).
15259 Possible values are:
15269 @code{'hybrid-sleep}.
15275 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
15276 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
15277 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
15278 notifications and ways to mount/unmount disks. Programs that talk to UDisks
15279 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
15282 @deffn {Scheme Procedure} colord-service [#:colord @var{colord}]
15283 Return a service that runs @command{colord}, a system service with a D-Bus
15284 interface to manage the color profiles of input and output devices such as
15285 screens and scanners. It is notably used by the GNOME Color Manager graphical
15286 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
15287 site} for more information.
15290 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
15291 Return a configuration allowing an application to access GeoClue
15292 location data. @var{name} is the Desktop ID of the application, without
15293 the @code{.desktop} part. If @var{allowed?} is true, the application
15294 will have access to location information by default. The boolean
15295 @var{system?} value indicates whether an application is a system component
15296 or not. Finally @var{users} is a list of UIDs of all users for which
15297 this application is allowed location info access. An empty users list
15298 means that all users are allowed.
15301 @defvr {Scheme Variable} %standard-geoclue-applications
15302 The standard list of well-known GeoClue application configurations,
15303 granting authority to the GNOME date-and-time utility to ask for the
15304 current location in order to set the time zone, and allowing the
15305 IceCat and Epiphany web browsers to request location information.
15306 IceCat and Epiphany both query the user before allowing a web page to
15307 know the user's location.
15310 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
15311 [#:whitelist '()] @
15312 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
15313 [#:submit-data? #f]
15314 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
15315 [#:submission-nick "geoclue"] @
15316 [#:applications %standard-geoclue-applications]
15317 Return a service that runs the GeoClue location service. This service
15318 provides a D-Bus interface to allow applications to request access to a
15319 user's physical location, and optionally to add information to online
15320 location databases. See
15321 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
15322 web site} for more information.
15325 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
15326 [@w{#:auto-enable? #f}]
15327 Return a service that runs the @command{bluetoothd} daemon, which
15328 manages all the Bluetooth devices and provides a number of D-Bus
15329 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
15330 powered automatically at boot, which can be useful when using a
15331 bluetooth keyboard or mouse.
15333 Users need to be in the @code{lp} group to access the D-Bus service.
15336 @node Sound Services
15337 @subsection Sound Services
15339 @cindex sound support
15341 @cindex PulseAudio, sound support
15343 The @code{(gnu services sound)} module provides a service to configure the
15344 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
15345 preferred ALSA output driver.
15347 @deffn {Scheme Variable} alsa-service-type
15348 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
15349 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
15350 configuration file. The value for this type is a @command{alsa-configuration}
15351 record as in this example:
15354 (service alsa-service-type)
15357 See below for details about @code{alsa-configuration}.
15360 @deftp {Data Type} alsa-configuration
15361 Data type representing the configuration for @code{alsa-service}.
15364 @item @code{alsa-plugins} (default: @var{alsa-plugins})
15365 @code{alsa-plugins} package to use.
15367 @item @code{pulseaudio?} (default: @var{#t})
15368 Whether ALSA applications should transparently be made to use the
15369 @uref{http://www.pulseaudio.org/, PulseAudio} sound server.
15371 Using PulseAudio allows you to run several sound-producing applications
15372 at the same time and to individual control them @i{via}
15373 @command{pavucontrol}, among other things.
15375 @item @code{extra-options} (default: @var{""})
15376 String to append to the @file{/etc/asound.conf} file.
15381 Individual users who want to override the system configuration of ALSA can do
15382 it with the @file{~/.asoundrc} file:
15385 # In guix, we have to specify the absolute path for plugins.
15387 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
15390 # Routing ALSA to jack:
15391 # <http://jackaudio.org/faq/routing_alsa.html>.
15395 0 system:playback_1
15396 1 system:playback_2
15413 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
15417 @node Database Services
15418 @subsection Database Services
15422 The @code{(gnu services databases)} module provides the following services.
15424 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
15425 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
15426 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
15427 Return a service that runs @var{postgresql}, the PostgreSQL database
15430 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
15431 creates a database cluster with @var{locale} as the default
15432 locale, stored in @var{data-directory}. It then listens on @var{port}.
15434 @cindex postgresql extension-packages
15435 Additional extensions are loaded from packages listed in
15436 @var{extension-packages}. Extensions are available at runtime. For instance,
15437 to create a geographic database using the @code{postgis} extension, a user can
15438 configure the postgresql-service as in this example:
15442 (use-package-modules databases geo)
15446 ;; postgresql is required to run `psql' but postgis is not required for
15447 ;; proper operation.
15448 (packages (cons* postgresql %base-packages))
15451 (postgresql-service #:extension-packages (list postgis))
15455 Then the extension becomes visible and you can initialise an empty geographic
15456 database in this way:
15460 > create database postgistest;
15461 > \connect postgistest;
15462 > create extension postgis;
15463 > create extension postgis_topology;
15466 There is no need to add this field for contrib extensions such as hstore or
15467 dblink as they are already loadable by postgresql. This field is only
15468 required to add extensions provided by other packages.
15471 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
15472 Return a service that runs @command{mysqld}, the MySQL or MariaDB
15475 The optional @var{config} argument specifies the configuration for
15476 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
15479 @deftp {Data Type} mysql-configuration
15480 Data type representing the configuration of @var{mysql-service}.
15483 @item @code{mysql} (default: @var{mariadb})
15484 Package object of the MySQL database server, can be either @var{mariadb}
15487 For MySQL, a temporary root password will be displayed at activation time.
15488 For MariaDB, the root password is empty.
15490 @item @code{port} (default: @code{3306})
15491 TCP port on which the database server listens for incoming connections.
15495 @defvr {Scheme Variable} memcached-service-type
15496 This is the service type for the @uref{https://memcached.org/,
15497 Memcached} service, which provides a distributed in memory cache. The
15498 value for the service type is a @code{memcached-configuration} object.
15502 (service memcached-service-type)
15505 @deftp {Data Type} memcached-configuration
15506 Data type representing the configuration of memcached.
15509 @item @code{memcached} (default: @code{memcached})
15510 The Memcached package to use.
15512 @item @code{interfaces} (default: @code{'("0.0.0.0")})
15513 Network interfaces on which to listen.
15515 @item @code{tcp-port} (default: @code{11211})
15516 Port on which to accept connections on,
15518 @item @code{udp-port} (default: @code{11211})
15519 Port on which to accept UDP connections on, a value of 0 will disable
15520 listening on a UDP socket.
15522 @item @code{additional-options} (default: @code{'()})
15523 Additional command line options to pass to @code{memcached}.
15527 @defvr {Scheme Variable} mongodb-service-type
15528 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
15529 The value for the service type is a @code{mongodb-configuration} object.
15533 (service mongodb-service-type)
15536 @deftp {Data Type} mongodb-configuration
15537 Data type representing the configuration of mongodb.
15540 @item @code{mongodb} (default: @code{mongodb})
15541 The MongoDB package to use.
15543 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
15544 The configuration file for MongoDB.
15546 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
15547 This value is used to create the directory, so that it exists and is
15548 owned by the mongodb user. It should match the data-directory which
15549 MongoDB is configured to use through the configuration file.
15553 @defvr {Scheme Variable} redis-service-type
15554 This is the service type for the @uref{https://redis.io/, Redis}
15555 key/value store, whose value is a @code{redis-configuration} object.
15558 @deftp {Data Type} redis-configuration
15559 Data type representing the configuration of redis.
15562 @item @code{redis} (default: @code{redis})
15563 The Redis package to use.
15565 @item @code{bind} (default: @code{"127.0.0.1"})
15566 Network interface on which to listen.
15568 @item @code{port} (default: @code{6379})
15569 Port on which to accept connections on, a value of 0 will disable
15570 listening on a TCP socket.
15572 @item @code{working-directory} (default: @code{"/var/lib/redis"})
15573 Directory in which to store the database and related files.
15577 @node Mail Services
15578 @subsection Mail Services
15582 The @code{(gnu services mail)} module provides Guix service definitions
15583 for email services: IMAP, POP3, and LMTP servers, as well as mail
15584 transport agents (MTAs). Lots of acronyms! These services are detailed
15585 in the subsections below.
15587 @subsubheading Dovecot Service
15589 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
15590 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
15593 By default, Dovecot does not need much configuration; the default
15594 configuration object created by @code{(dovecot-configuration)} will
15595 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
15596 certificate will be generated for TLS-protected connections, though
15597 Dovecot will also listen on cleartext ports by default. There are a
15598 number of options, though, which mail administrators might need to change,
15599 and as is the case with other services, Guix allows the system
15600 administrator to specify these parameters via a uniform Scheme interface.
15602 For example, to specify that mail is located at @code{maildir~/.mail},
15603 one would instantiate the Dovecot service like this:
15606 (dovecot-service #:config
15607 (dovecot-configuration
15608 (mail-location "maildir:~/.mail")))
15611 The available configuration parameters follow. Each parameter
15612 definition is preceded by its type; for example, @samp{string-list foo}
15613 indicates that the @code{foo} parameter should be specified as a list of
15614 strings. There is also a way to specify the configuration as a string,
15615 if you have an old @code{dovecot.conf} file that you want to port over
15616 from some other system; see the end for more details.
15618 @c The following documentation was initially generated by
15619 @c (generate-documentation) in (gnu services mail). Manually maintained
15620 @c documentation is better, so we shouldn't hesitate to edit below as
15621 @c needed. However if the change you want to make to this documentation
15622 @c can be done in an automated way, it's probably easier to change
15623 @c (generate-documentation) than to make it below and have to deal with
15624 @c the churn as dovecot updates.
15626 Available @code{dovecot-configuration} fields are:
15628 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
15629 The dovecot package.
15632 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
15633 A list of IPs or hosts where to listen for connections. @samp{*}
15634 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
15635 interfaces. If you want to specify non-default ports or anything more
15636 complex, customize the address and port fields of the
15637 @samp{inet-listener} of the specific services you are interested in.
15640 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
15641 List of protocols we want to serve. Available protocols include
15642 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
15644 Available @code{protocol-configuration} fields are:
15646 @deftypevr {@code{protocol-configuration} parameter} string name
15647 The name of the protocol.
15650 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
15651 UNIX socket path to the master authentication server to find users.
15652 This is used by imap (for shared users) and lda.
15653 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
15656 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
15657 Space separated list of plugins to load.
15660 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
15661 Maximum number of IMAP connections allowed for a user from each IP
15662 address. NOTE: The username is compared case-sensitively.
15663 Defaults to @samp{10}.
15668 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
15669 List of services to enable. Available services include @samp{imap},
15670 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
15673 Available @code{service-configuration} fields are:
15675 @deftypevr {@code{service-configuration} parameter} string kind
15676 The service kind. Valid values include @code{director},
15677 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
15678 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
15679 @code{tcpwrap}, @code{quota-warning}, or anything else.
15682 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
15683 Listeners for the service. A listener is either a
15684 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
15685 an @code{inet-listener-configuration}.
15686 Defaults to @samp{()}.
15688 Available @code{unix-listener-configuration} fields are:
15690 @deftypevr {@code{unix-listener-configuration} parameter} string path
15691 Path to the file, relative to @code{base-dir} field. This is also used as
15695 @deftypevr {@code{unix-listener-configuration} parameter} string mode
15696 The access mode for the socket.
15697 Defaults to @samp{"0600"}.
15700 @deftypevr {@code{unix-listener-configuration} parameter} string user
15701 The user to own the socket.
15702 Defaults to @samp{""}.
15705 @deftypevr {@code{unix-listener-configuration} parameter} string group
15706 The group to own the socket.
15707 Defaults to @samp{""}.
15711 Available @code{fifo-listener-configuration} fields are:
15713 @deftypevr {@code{fifo-listener-configuration} parameter} string path
15714 Path to the file, relative to @code{base-dir} field. This is also used as
15718 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
15719 The access mode for the socket.
15720 Defaults to @samp{"0600"}.
15723 @deftypevr {@code{fifo-listener-configuration} parameter} string user
15724 The user to own the socket.
15725 Defaults to @samp{""}.
15728 @deftypevr {@code{fifo-listener-configuration} parameter} string group
15729 The group to own the socket.
15730 Defaults to @samp{""}.
15734 Available @code{inet-listener-configuration} fields are:
15736 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
15737 The protocol to listen for.
15740 @deftypevr {@code{inet-listener-configuration} parameter} string address
15741 The address on which to listen, or empty for all addresses.
15742 Defaults to @samp{""}.
15745 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
15746 The port on which to listen.
15749 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
15750 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
15752 Defaults to @samp{#t}.
15757 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
15758 Maximum number of simultaneous client connections per process. Once
15759 this number of connections is received, the next incoming connection
15760 will prompt Dovecot to spawn another process. If set to 0,
15761 @code{default-client-limit} is used instead.
15763 Defaults to @samp{0}.
15767 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
15768 Number of connections to handle before starting a new process.
15769 Typically the only useful values are 0 (unlimited) or 1. 1 is more
15770 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
15771 Defaults to @samp{1}.
15775 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
15776 Maximum number of processes that can exist for this service. If set to
15777 0, @code{default-process-limit} is used instead.
15779 Defaults to @samp{0}.
15783 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
15784 Number of processes to always keep waiting for more connections.
15785 Defaults to @samp{0}.
15788 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
15789 If you set @samp{service-count 0}, you probably need to grow
15791 Defaults to @samp{256000000}.
15796 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
15797 Dict configuration, as created by the @code{dict-configuration}
15800 Available @code{dict-configuration} fields are:
15802 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
15803 A list of key-value pairs that this dict should hold.
15804 Defaults to @samp{()}.
15809 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
15810 A list of passdb configurations, each one created by the
15811 @code{passdb-configuration} constructor.
15813 Available @code{passdb-configuration} fields are:
15815 @deftypevr {@code{passdb-configuration} parameter} string driver
15816 The driver that the passdb should use. Valid values include
15817 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
15819 Defaults to @samp{"pam"}.
15822 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
15823 Space separated list of arguments to the passdb driver.
15824 Defaults to @samp{""}.
15829 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
15830 List of userdb configurations, each one created by the
15831 @code{userdb-configuration} constructor.
15833 Available @code{userdb-configuration} fields are:
15835 @deftypevr {@code{userdb-configuration} parameter} string driver
15836 The driver that the userdb should use. Valid values include
15837 @samp{passwd} and @samp{static}.
15838 Defaults to @samp{"passwd"}.
15841 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
15842 Space separated list of arguments to the userdb driver.
15843 Defaults to @samp{""}.
15846 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
15847 Override fields from passwd.
15848 Defaults to @samp{()}.
15853 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
15854 Plug-in configuration, created by the @code{plugin-configuration}
15858 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
15859 List of namespaces. Each item in the list is created by the
15860 @code{namespace-configuration} constructor.
15862 Available @code{namespace-configuration} fields are:
15864 @deftypevr {@code{namespace-configuration} parameter} string name
15865 Name for this namespace.
15868 @deftypevr {@code{namespace-configuration} parameter} string type
15869 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
15870 Defaults to @samp{"private"}.
15873 @deftypevr {@code{namespace-configuration} parameter} string separator
15874 Hierarchy separator to use. You should use the same separator for
15875 all namespaces or some clients get confused. @samp{/} is usually a good
15876 one. The default however depends on the underlying mail storage
15878 Defaults to @samp{""}.
15881 @deftypevr {@code{namespace-configuration} parameter} string prefix
15882 Prefix required to access this namespace. This needs to be
15883 different for all namespaces. For example @samp{Public/}.
15884 Defaults to @samp{""}.
15887 @deftypevr {@code{namespace-configuration} parameter} string location
15888 Physical location of the mailbox. This is in the same format as
15889 mail_location, which is also the default for it.
15890 Defaults to @samp{""}.
15893 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
15894 There can be only one INBOX, and this setting defines which
15896 Defaults to @samp{#f}.
15899 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
15900 If namespace is hidden, it's not advertised to clients via NAMESPACE
15901 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
15902 useful when converting from another server with different namespaces
15903 which you want to deprecate but still keep working. For example you can
15904 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
15906 Defaults to @samp{#f}.
15909 @deftypevr {@code{namespace-configuration} parameter} boolean list?
15910 Show the mailboxes under this namespace with the LIST command. This
15911 makes the namespace visible for clients that do not support the NAMESPACE
15912 extension. The special @code{children} value lists child mailboxes, but
15913 hides the namespace prefix.
15914 Defaults to @samp{#t}.
15917 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
15918 Namespace handles its own subscriptions. If set to @code{#f}, the
15919 parent namespace handles them. The empty prefix should always have this
15921 Defaults to @samp{#t}.
15924 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
15925 List of predefined mailboxes in this namespace.
15926 Defaults to @samp{()}.
15928 Available @code{mailbox-configuration} fields are:
15930 @deftypevr {@code{mailbox-configuration} parameter} string name
15931 Name for this mailbox.
15934 @deftypevr {@code{mailbox-configuration} parameter} string auto
15935 @samp{create} will automatically create this mailbox.
15936 @samp{subscribe} will both create and subscribe to the mailbox.
15937 Defaults to @samp{"no"}.
15940 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
15941 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
15942 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
15943 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
15944 Defaults to @samp{()}.
15951 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
15952 Base directory where to store runtime data.
15953 Defaults to @samp{"/var/run/dovecot/"}.
15956 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
15957 Greeting message for clients.
15958 Defaults to @samp{"Dovecot ready."}.
15961 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
15962 List of trusted network ranges. Connections from these IPs are
15963 allowed to override their IP addresses and ports (for logging and for
15964 authentication checks). @samp{disable-plaintext-auth} is also ignored
15965 for these networks. Typically you would specify your IMAP proxy servers
15967 Defaults to @samp{()}.
15970 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
15971 List of login access check sockets (e.g.@: tcpwrap).
15972 Defaults to @samp{()}.
15975 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
15976 Show more verbose process titles (in ps). Currently shows user name
15977 and IP address. Useful for seeing who is actually using the IMAP
15978 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
15980 Defaults to @samp{#f}.
15983 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
15984 Should all processes be killed when Dovecot master process shuts down.
15985 Setting this to @code{#f} means that Dovecot can be upgraded without
15986 forcing existing client connections to close (although that could also
15987 be a problem if the upgrade is e.g.@: due to a security fix).
15988 Defaults to @samp{#t}.
15991 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
15992 If non-zero, run mail commands via this many connections to doveadm
15993 server, instead of running them directly in the same process.
15994 Defaults to @samp{0}.
15997 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
15998 UNIX socket or host:port used for connecting to doveadm server.
15999 Defaults to @samp{"doveadm-server"}.
16002 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
16003 List of environment variables that are preserved on Dovecot startup
16004 and passed down to all of its child processes. You can also give
16005 key=value pairs to always set specific settings.
16008 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
16009 Disable LOGIN command and all other plaintext authentications unless
16010 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
16011 matches the local IP (i.e.@: you're connecting from the same computer),
16012 the connection is considered secure and plaintext authentication is
16013 allowed. See also ssl=required setting.
16014 Defaults to @samp{#t}.
16017 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
16018 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
16019 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
16020 for caching to be used.
16021 Defaults to @samp{0}.
16024 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
16025 Time to live for cached data. After TTL expires the cached record
16026 is no longer used, *except* if the main database lookup returns internal
16027 failure. We also try to handle password changes automatically: If
16028 user's previous authentication was successful, but this one wasn't, the
16029 cache isn't used. For now this works only with plaintext
16031 Defaults to @samp{"1 hour"}.
16034 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
16035 TTL for negative hits (user not found, password mismatch).
16036 0 disables caching them completely.
16037 Defaults to @samp{"1 hour"}.
16040 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
16041 List of realms for SASL authentication mechanisms that need them.
16042 You can leave it empty if you don't want to support multiple realms.
16043 Many clients simply use the first one listed here, so keep the default
16045 Defaults to @samp{()}.
16048 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
16049 Default realm/domain to use if none was specified. This is used for
16050 both SASL realms and appending @@domain to username in plaintext
16052 Defaults to @samp{""}.
16055 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
16056 List of allowed characters in username. If the user-given username
16057 contains a character not listed in here, the login automatically fails.
16058 This is just an extra check to make sure user can't exploit any
16059 potential quote escaping vulnerabilities with SQL/LDAP databases. If
16060 you want to allow all characters, set this value to empty.
16061 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
16064 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
16065 Username character translations before it's looked up from
16066 databases. The value contains series of from -> to characters. For
16067 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
16068 translated to @samp{@@}.
16069 Defaults to @samp{""}.
16072 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
16073 Username formatting before it's looked up from databases. You can
16074 use the standard variables here, e.g.@: %Lu would lowercase the username,
16075 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
16076 change the @samp{@@} into @samp{-AT-}. This translation is done after
16077 @samp{auth-username-translation} changes.
16078 Defaults to @samp{"%Lu"}.
16081 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
16082 If you want to allow master users to log in by specifying the master
16083 username within the normal username string (i.e.@: not using SASL
16084 mechanism's support for it), you can specify the separator character
16085 here. The format is then <username><separator><master username>.
16086 UW-IMAP uses @samp{*} as the separator, so that could be a good
16088 Defaults to @samp{""}.
16091 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
16092 Username to use for users logging in with ANONYMOUS SASL
16094 Defaults to @samp{"anonymous"}.
16097 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
16098 Maximum number of dovecot-auth worker processes. They're used to
16099 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
16100 They're automatically created and destroyed as needed.
16101 Defaults to @samp{30}.
16104 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
16105 Host name to use in GSSAPI principal names. The default is to use
16106 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
16107 allow all keytab entries.
16108 Defaults to @samp{""}.
16111 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
16112 Kerberos keytab to use for the GSSAPI mechanism. Will use the
16113 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
16114 need to change the auth service to run as root to be able to read this
16116 Defaults to @samp{""}.
16119 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
16120 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
16121 and @samp{ntlm-auth} helper.
16122 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
16123 Defaults to @samp{#f}.
16126 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
16127 Path for Samba's @samp{ntlm-auth} helper binary.
16128 Defaults to @samp{"/usr/bin/ntlm_auth"}.
16131 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
16132 Time to delay before replying to failed authentications.
16133 Defaults to @samp{"2 secs"}.
16136 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
16137 Require a valid SSL client certificate or the authentication
16139 Defaults to @samp{#f}.
16142 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
16143 Take the username from client's SSL certificate, using
16144 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
16146 Defaults to @samp{#f}.
16149 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
16150 List of wanted authentication mechanisms. Supported mechanisms are:
16151 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
16152 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
16153 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
16154 @samp{disable-plaintext-auth} setting.
16157 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
16158 List of IPs or hostnames to all director servers, including ourself.
16159 Ports can be specified as ip:port. The default port is the same as what
16160 director service's @samp{inet-listener} is using.
16161 Defaults to @samp{()}.
16164 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
16165 List of IPs or hostnames to all backend mail servers. Ranges are
16166 allowed too, like 10.0.0.10-10.0.0.30.
16167 Defaults to @samp{()}.
16170 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
16171 How long to redirect users to a specific server after it no longer
16172 has any connections.
16173 Defaults to @samp{"15 min"}.
16176 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
16177 How the username is translated before being hashed. Useful values
16178 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
16179 are shared within domain.
16180 Defaults to @samp{"%Lu"}.
16183 @deftypevr {@code{dovecot-configuration} parameter} string log-path
16184 Log file to use for error messages. @samp{syslog} logs to syslog,
16185 @samp{/dev/stderr} logs to stderr.
16186 Defaults to @samp{"syslog"}.
16189 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
16190 Log file to use for informational messages. Defaults to
16192 Defaults to @samp{""}.
16195 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
16196 Log file to use for debug messages. Defaults to
16197 @samp{info-log-path}.
16198 Defaults to @samp{""}.
16201 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
16202 Syslog facility to use if you're logging to syslog. Usually if you
16203 don't want to use @samp{mail}, you'll use local0..local7. Also other
16204 standard facilities are supported.
16205 Defaults to @samp{"mail"}.
16208 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
16209 Log unsuccessful authentication attempts and the reasons why they
16211 Defaults to @samp{#f}.
16214 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
16215 In case of password mismatches, log the attempted password. Valid
16216 values are no, plain and sha1. sha1 can be useful for detecting brute
16217 force password attempts vs. user simply trying the same password over
16218 and over again. You can also truncate the value to n chars by appending
16219 ":n" (e.g.@: sha1:6).
16220 Defaults to @samp{"no"}.
16223 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
16224 Even more verbose logging for debugging purposes. Shows for example
16226 Defaults to @samp{#f}.
16229 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
16230 In case of password mismatches, log the passwords and used scheme so
16231 the problem can be debugged. Enabling this also enables
16233 Defaults to @samp{#f}.
16236 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
16237 Enable mail process debugging. This can help you figure out why
16238 Dovecot isn't finding your mails.
16239 Defaults to @samp{#f}.
16242 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
16243 Show protocol level SSL errors.
16244 Defaults to @samp{#f}.
16247 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
16248 Prefix for each line written to log file. % codes are in
16249 strftime(3) format.
16250 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
16253 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
16254 List of elements we want to log. The elements which have a
16255 non-empty variable value are joined together to form a comma-separated
16259 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
16260 Login log format. %s contains @samp{login-log-format-elements}
16261 string, %$ contains the data we want to log.
16262 Defaults to @samp{"%$: %s"}.
16265 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
16266 Log prefix for mail processes. See doc/wiki/Variables.txt for list
16267 of possible variables you can use.
16268 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
16271 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
16272 Format to use for logging mail deliveries. You can use variables:
16275 Delivery status message (e.g.@: @samp{saved to INBOX})
16287 Defaults to @samp{"msgid=%m: %$"}.
16290 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
16291 Location for users' mailboxes. The default is empty, which means
16292 that Dovecot tries to find the mailboxes automatically. This won't work
16293 if the user doesn't yet have any mail, so you should explicitly tell
16294 Dovecot the full location.
16296 If you're using mbox, giving a path to the INBOX
16297 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
16298 where the other mailboxes are kept. This is called the "root mail
16299 directory", and it must be the first path given in the
16300 @samp{mail-location} setting.
16302 There are a few special variables you can use, eg.:
16308 user part in user@@domain, same as %u if there's no domain
16310 domain part in user@@domain, empty if there's no domain
16315 See doc/wiki/Variables.txt for full list. Some examples:
16317 @item maildir:~/Maildir
16318 @item mbox:~/mail:INBOX=/var/mail/%u
16319 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
16321 Defaults to @samp{""}.
16324 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
16325 System user and group used to access mails. If you use multiple,
16326 userdb can override these by returning uid or gid fields. You can use
16327 either numbers or names. <doc/wiki/UserIds.txt>.
16328 Defaults to @samp{""}.
16331 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
16333 Defaults to @samp{""}.
16336 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
16337 Group to enable temporarily for privileged operations. Currently
16338 this is used only with INBOX when either its initial creation or
16339 dotlocking fails. Typically this is set to "mail" to give access to
16341 Defaults to @samp{""}.
16344 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
16345 Grant access to these supplementary groups for mail processes.
16346 Typically these are used to set up access to shared mailboxes. Note
16347 that it may be dangerous to set these if users can create
16348 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
16349 could allow a user to delete others' mailboxes, or ln -s
16350 /secret/shared/box ~/mail/mybox would allow reading it).
16351 Defaults to @samp{""}.
16354 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
16355 Allow full file system access to clients. There's no access checks
16356 other than what the operating system does for the active UID/GID. It
16357 works with both maildir and mboxes, allowing you to prefix mailboxes
16358 names with e.g.@: /path/ or ~user/.
16359 Defaults to @samp{#f}.
16362 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
16363 Don't use mmap() at all. This is required if you store indexes to
16364 shared file systems (NFS or clustered file system).
16365 Defaults to @samp{#f}.
16368 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
16369 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
16370 supports @samp{O_EXCL} since version 3, so this should be safe to use
16371 nowadays by default.
16372 Defaults to @samp{#t}.
16375 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
16376 When to use fsync() or fdatasync() calls:
16379 Whenever necessary to avoid losing important data
16381 Useful with e.g.@: NFS when write()s are delayed
16383 Never use it (best performance, but crashes can lose data).
16385 Defaults to @samp{"optimized"}.
16388 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
16389 Mail storage exists in NFS. Set this to yes to make Dovecot flush
16390 NFS caches whenever needed. If you're using only a single mail server
16392 Defaults to @samp{#f}.
16395 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
16396 Mail index files also exist in NFS. Setting this to yes requires
16397 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
16398 Defaults to @samp{#f}.
16401 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
16402 Locking method for index files. Alternatives are fcntl, flock and
16403 dotlock. Dotlocking uses some tricks which may create more disk I/O
16404 than other locking methods. NFS users: flock doesn't work, remember to
16405 change @samp{mmap-disable}.
16406 Defaults to @samp{"fcntl"}.
16409 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
16410 Directory in which LDA/LMTP temporarily stores incoming mails >128
16412 Defaults to @samp{"/tmp"}.
16415 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
16416 Valid UID range for users. This is mostly to make sure that users can't
16417 log in as daemons or other system users. Note that denying root logins is
16418 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
16420 Defaults to @samp{500}.
16423 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
16425 Defaults to @samp{0}.
16428 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
16429 Valid GID range for users. Users having non-valid GID as primary group ID
16430 aren't allowed to log in. If user belongs to supplementary groups with
16431 non-valid GIDs, those groups are not set.
16432 Defaults to @samp{1}.
16435 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
16437 Defaults to @samp{0}.
16440 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
16441 Maximum allowed length for mail keyword name. It's only forced when
16442 trying to create new keywords.
16443 Defaults to @samp{50}.
16446 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
16447 List of directories under which chrooting is allowed for mail
16448 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
16449 too). This setting doesn't affect @samp{login-chroot}
16450 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
16451 "/./" in home dirs are ignored. WARNING: Never add directories here
16452 which local users can modify, that may lead to root exploit. Usually
16453 this should be done only if you don't allow shell access for users.
16454 <doc/wiki/Chrooting.txt>.
16455 Defaults to @samp{()}.
16458 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
16459 Default chroot directory for mail processes. This can be overridden
16460 for specific users in user database by giving /./ in user's home
16461 directory (e.g.@: /home/./user chroots into /home). Note that usually
16462 there is no real need to do chrooting, Dovecot doesn't allow users to
16463 access files outside their mail directory anyway. If your home
16464 directories are prefixed with the chroot directory, append "/."@: to
16465 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
16466 Defaults to @samp{""}.
16469 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
16470 UNIX socket path to master authentication server to find users.
16471 This is used by imap (for shared users) and lda.
16472 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16475 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
16476 Directory where to look up mail plugins.
16477 Defaults to @samp{"/usr/lib/dovecot"}.
16480 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
16481 List of plugins to load for all services. Plugins specific to IMAP,
16482 LDA, etc.@: are added to this list in their own .conf files.
16483 Defaults to @samp{()}.
16486 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
16487 The minimum number of mails in a mailbox before updates are done to
16488 cache file. This allows optimizing Dovecot's behavior to do less disk
16489 writes at the cost of more disk reads.
16490 Defaults to @samp{0}.
16493 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
16494 When IDLE command is running, mailbox is checked once in a while to
16495 see if there are any new mails or other changes. This setting defines
16496 the minimum time to wait between those checks. Dovecot can also use
16497 dnotify, inotify and kqueue to find out immediately when changes
16499 Defaults to @samp{"30 secs"}.
16502 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
16503 Save mails with CR+LF instead of plain LF. This makes sending those
16504 mails take less CPU, especially with sendfile() syscall with Linux and
16505 FreeBSD. But it also creates a bit more disk I/O which may just make it
16506 slower. Also note that if other software reads the mboxes/maildirs,
16507 they may handle the extra CRs wrong and cause problems.
16508 Defaults to @samp{#f}.
16511 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
16512 By default LIST command returns all entries in maildir beginning
16513 with a dot. Enabling this option makes Dovecot return only entries
16514 which are directories. This is done by stat()ing each entry, so it
16515 causes more disk I/O.
16516 (For systems setting struct @samp{dirent->d_type} this check is free
16517 and it's done always regardless of this setting).
16518 Defaults to @samp{#f}.
16521 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
16522 When copying a message, do it with hard links whenever possible.
16523 This makes the performance much better, and it's unlikely to have any
16525 Defaults to @samp{#t}.
16528 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
16529 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
16530 directory only when its mtime changes unexpectedly or when we can't find
16531 the mail otherwise.
16532 Defaults to @samp{#f}.
16535 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
16536 Which locking methods to use for locking mbox. There are four
16541 Create <mailbox>.lock file. This is the oldest and most NFS-safe
16542 solution. If you want to use /var/mail/ like directory, the users will
16543 need write access to that directory.
16545 Same as dotlock, but if it fails because of permissions or because there
16546 isn't enough disk space, just skip it.
16548 Use this if possible. Works with NFS too if lockd is used.
16550 May not exist in all systems. Doesn't work with NFS.
16552 May not exist in all systems. Doesn't work with NFS.
16555 You can use multiple locking methods; if you do the order they're declared
16556 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
16557 locking methods as well. Some operating systems don't allow using some of
16558 them simultaneously.
16561 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
16565 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
16566 Maximum time to wait for lock (all of them) before aborting.
16567 Defaults to @samp{"5 mins"}.
16570 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
16571 If dotlock exists but the mailbox isn't modified in any way,
16572 override the lock file after this much time.
16573 Defaults to @samp{"2 mins"}.
16576 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
16577 When mbox changes unexpectedly we have to fully read it to find out
16578 what changed. If the mbox is large this can take a long time. Since
16579 the change is usually just a newly appended mail, it'd be faster to
16580 simply read the new mails. If this setting is enabled, Dovecot does
16581 this but still safely fallbacks to re-reading the whole mbox file
16582 whenever something in mbox isn't how it's expected to be. The only real
16583 downside to this setting is that if some other MUA changes message
16584 flags, Dovecot doesn't notice it immediately. Note that a full sync is
16585 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
16586 Defaults to @samp{#t}.
16589 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
16590 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
16591 EXAMINE, EXPUNGE or CHECK commands. If this is set,
16592 @samp{mbox-dirty-syncs} is ignored.
16593 Defaults to @samp{#f}.
16596 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
16597 Delay writing mbox headers until doing a full write sync (EXPUNGE
16598 and CHECK commands and when closing the mailbox). This is especially
16599 useful for POP3 where clients often delete all mails. The downside is
16600 that our changes aren't immediately visible to other MUAs.
16601 Defaults to @samp{#t}.
16604 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
16605 If mbox size is smaller than this (e.g.@: 100k), don't write index
16606 files. If an index file already exists it's still read, just not
16608 Defaults to @samp{0}.
16611 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
16612 Maximum dbox file size until it's rotated.
16613 Defaults to @samp{10000000}.
16616 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
16617 Maximum dbox file age until it's rotated. Typically in days. Day
16618 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
16620 Defaults to @samp{"1d"}.
16623 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
16624 When creating new mdbox files, immediately preallocate their size to
16625 @samp{mdbox-rotate-size}. This setting currently works only in Linux
16626 with some file systems (ext4, xfs).
16627 Defaults to @samp{#f}.
16630 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
16631 sdbox and mdbox support saving mail attachments to external files,
16632 which also allows single instance storage for them. Other backends
16633 don't support this for now.
16635 WARNING: This feature hasn't been tested much yet. Use at your own risk.
16637 Directory root where to store mail attachments. Disabled, if empty.
16638 Defaults to @samp{""}.
16641 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
16642 Attachments smaller than this aren't saved externally. It's also
16643 possible to write a plugin to disable saving specific attachments
16645 Defaults to @samp{128000}.
16648 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
16649 File system backend to use for saving attachments:
16652 No SiS done by Dovecot (but this might help FS's own deduplication)
16654 SiS with immediate byte-by-byte comparison during saving
16655 @item sis-queue posix
16656 SiS with delayed comparison and deduplication.
16658 Defaults to @samp{"sis posix"}.
16661 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
16662 Hash format to use in attachment filenames. You can add any text and
16663 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
16664 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
16665 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
16666 Defaults to @samp{"%@{sha1@}"}.
16669 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
16671 Defaults to @samp{100}.
16674 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
16676 Defaults to @samp{1000}.
16679 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
16680 Default VSZ (virtual memory size) limit for service processes.
16681 This is mainly intended to catch and kill processes that leak memory
16682 before they eat up everything.
16683 Defaults to @samp{256000000}.
16686 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
16687 Login user is internally used by login processes. This is the most
16688 untrusted user in Dovecot system. It shouldn't have access to anything
16690 Defaults to @samp{"dovenull"}.
16693 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
16694 Internal user is used by unprivileged processes. It should be
16695 separate from login user, so that login processes can't disturb other
16697 Defaults to @samp{"dovecot"}.
16700 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
16701 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
16702 Defaults to @samp{"required"}.
16705 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
16706 PEM encoded X.509 SSL/TLS certificate (public key).
16707 Defaults to @samp{"</etc/dovecot/default.pem"}.
16710 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
16711 PEM encoded SSL/TLS private key. The key is opened before
16712 dropping root privileges, so keep the key file unreadable by anyone but
16714 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
16717 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
16718 If key file is password protected, give the password here.
16719 Alternatively give it when starting dovecot with -p parameter. Since
16720 this file is often world-readable, you may want to place this setting
16721 instead to a different.
16722 Defaults to @samp{""}.
16725 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
16726 PEM encoded trusted certificate authority. Set this only if you
16727 intend to use @samp{ssl-verify-client-cert? #t}. The file should
16728 contain the CA certificate(s) followed by the matching
16729 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
16730 Defaults to @samp{""}.
16733 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
16734 Require that CRL check succeeds for client certificates.
16735 Defaults to @samp{#t}.
16738 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
16739 Request client to send a certificate. If you also want to require
16740 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
16741 Defaults to @samp{#f}.
16744 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
16745 Which field from certificate to use for username. commonName and
16746 x500UniqueIdentifier are the usual choices. You'll also need to set
16747 @samp{auth-ssl-username-from-cert? #t}.
16748 Defaults to @samp{"commonName"}.
16751 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
16752 Minimum SSL protocol version to accept.
16753 Defaults to @samp{"TLSv1"}.
16756 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
16757 SSL ciphers to use.
16758 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
16761 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
16762 SSL crypto device to use, for valid values run "openssl engine".
16763 Defaults to @samp{""}.
16766 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
16767 Address to use when sending rejection mails.
16768 %d expands to recipient domain.
16769 Defaults to @samp{"postmaster@@%d"}.
16772 @deftypevr {@code{dovecot-configuration} parameter} string hostname
16773 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
16774 and in LMTP replies. Default is the system's real hostname@@domain.
16775 Defaults to @samp{""}.
16778 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
16779 If user is over quota, return with temporary failure instead of
16781 Defaults to @samp{#f}.
16784 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
16785 Binary to use for sending mails.
16786 Defaults to @samp{"/usr/sbin/sendmail"}.
16789 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
16790 If non-empty, send mails via this SMTP host[:port] instead of
16792 Defaults to @samp{""}.
16795 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
16796 Subject: header to use for rejection mails. You can use the same
16797 variables as for @samp{rejection-reason} below.
16798 Defaults to @samp{"Rejected: %s"}.
16801 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
16802 Human readable error message for rejection mails. You can use
16815 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
16818 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
16819 Delimiter character between local-part and detail in email
16821 Defaults to @samp{"+"}.
16824 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
16825 Header where the original recipient address (SMTP's RCPT TO:
16826 address) is taken from if not available elsewhere. With dovecot-lda -a
16827 parameter overrides this. A commonly used header for this is
16829 Defaults to @samp{""}.
16832 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
16833 Should saving a mail to a nonexistent mailbox automatically create
16835 Defaults to @samp{#f}.
16838 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
16839 Should automatically created mailboxes be also automatically
16841 Defaults to @samp{#f}.
16844 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
16845 Maximum IMAP command line length. Some clients generate very long
16846 command lines with huge mailboxes, so you may need to raise this if you
16847 get "Too long argument" or "IMAP command line too large" errors
16849 Defaults to @samp{64000}.
16852 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
16853 IMAP logout format string:
16856 total number of bytes read from client
16858 total number of bytes sent to client.
16860 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
16861 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@}"}.
16864 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
16865 Override the IMAP CAPABILITY response. If the value begins with '+',
16866 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
16867 Defaults to @samp{""}.
16870 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
16871 How long to wait between "OK Still here" notifications when client
16873 Defaults to @samp{"2 mins"}.
16876 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
16877 ID field names and values to send to clients. Using * as the value
16878 makes Dovecot use the default value. The following fields have default
16879 values currently: name, version, os, os-version, support-url,
16881 Defaults to @samp{""}.
16884 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
16885 ID fields sent by client to log. * means everything.
16886 Defaults to @samp{""}.
16889 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
16890 Workarounds for various client bugs:
16893 @item delay-newmail
16894 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
16895 CHECK commands. Some clients ignore them otherwise, for example OSX
16896 Mail (<v2.1). Outlook Express breaks more badly though, without this it
16897 may show user "Message no longer in server" errors. Note that OE6
16898 still breaks even with this workaround if synchronization is set to
16901 @item tb-extra-mailbox-sep
16902 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
16903 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
16904 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
16906 @item tb-lsub-flags
16907 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
16908 This makes Thunderbird realize they aren't selectable and show them
16909 greyed out, instead of only later giving "not selectable" popup error.
16911 Defaults to @samp{()}.
16914 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
16915 Host allowed in URLAUTH URLs sent by client. "*" allows all.
16916 Defaults to @samp{""}.
16920 Whew! Lots of configuration options. The nice thing about it though is
16921 that Guix has a complete interface to Dovecot's configuration
16922 language. This allows not only a nice way to declare configurations,
16923 but also offers reflective capabilities as well: users can write code to
16924 inspect and transform configurations from within Scheme.
16926 However, it could be that you just want to get a @code{dovecot.conf} up
16927 and running. In that case, you can pass an
16928 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
16929 @code{dovecot-service}. As its name indicates, an opaque configuration
16930 does not have easy reflective capabilities.
16932 Available @code{opaque-dovecot-configuration} fields are:
16934 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
16935 The dovecot package.
16938 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
16939 The contents of the @code{dovecot.conf}, as a string.
16942 For example, if your @code{dovecot.conf} is just the empty string, you
16943 could instantiate a dovecot service like this:
16946 (dovecot-service #:config
16947 (opaque-dovecot-configuration
16951 @subsubheading OpenSMTPD Service
16953 @deffn {Scheme Variable} opensmtpd-service-type
16954 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
16955 service, whose value should be an @code{opensmtpd-configuration} object
16956 as in this example:
16959 (service opensmtpd-service-type
16960 (opensmtpd-configuration
16961 (config-file (local-file "./my-smtpd.conf"))))
16965 @deftp {Data Type} opensmtpd-configuration
16966 Data type representing the configuration of opensmtpd.
16969 @item @code{package} (default: @var{opensmtpd})
16970 Package object of the OpenSMTPD SMTP server.
16972 @item @code{config-file} (default: @code{%default-opensmtpd-file})
16973 File-like object of the OpenSMTPD configuration file to use. By default
16974 it listens on the loopback network interface, and allows for mail from
16975 users and daemons on the local machine, as well as permitting email to
16976 remote servers. Run @command{man smtpd.conf} for more information.
16981 @subsubheading Exim Service
16983 @cindex mail transfer agent (MTA)
16984 @cindex MTA (mail transfer agent)
16987 @deffn {Scheme Variable} exim-service-type
16988 This is the type of the @uref{https://exim.org, Exim} mail transfer
16989 agent (MTA), whose value should be an @code{exim-configuration} object
16990 as in this example:
16993 (service exim-service-type
16994 (exim-configuration
16995 (config-file (local-file "./my-exim.conf"))))
16999 In order to use an @code{exim-service-type} service you must also have a
17000 @code{mail-aliases-service-type} service present in your
17001 @code{operating-system} (even if it has no aliases).
17003 @deftp {Data Type} exim-configuration
17004 Data type representing the configuration of exim.
17007 @item @code{package} (default: @var{exim})
17008 Package object of the Exim server.
17010 @item @code{config-file} (default: @code{#f})
17011 File-like object of the Exim configuration file to use. If its value is
17012 @code{#f} then use the default configuration file from the package
17013 provided in @code{package}. The resulting configuration file is loaded
17014 after setting the @code{exim_user} and @code{exim_group} configuration
17020 @subsubheading Getmail service
17025 @deffn {Scheme Variable} getmail-service-type
17026 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
17027 mail retriever, whose value should be an @code{getmail-configuration}.
17030 Available @code{getmail-configuration} fields are:
17032 @deftypevr {@code{getmail-configuration} parameter} symbol name
17033 A symbol to identify the getmail service.
17035 Defaults to @samp{"unset"}.
17039 @deftypevr {@code{getmail-configuration} parameter} package package
17040 The getmail package to use.
17044 @deftypevr {@code{getmail-configuration} parameter} string user
17045 The user to run getmail as.
17047 Defaults to @samp{"getmail"}.
17051 @deftypevr {@code{getmail-configuration} parameter} string group
17052 The group to run getmail as.
17054 Defaults to @samp{"getmail"}.
17058 @deftypevr {@code{getmail-configuration} parameter} string directory
17059 The getmail directory to use.
17061 Defaults to @samp{"/var/lib/getmail/default"}.
17065 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
17066 The getmail configuration file to use.
17068 Available @code{getmail-configuration-file} fields are:
17070 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
17071 What mail account to retrieve mail from, and how to access that account.
17073 Available @code{getmail-retriever-configuration} fields are:
17075 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
17076 The type of mail retriever to use. Valid values include @samp{passwd}
17079 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
17083 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
17084 Space separated list of arguments to the userdb driver.
17086 Defaults to @samp{unset}.
17090 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
17091 Space separated list of arguments to the userdb driver.
17093 Defaults to @samp{unset}.
17097 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
17098 Space separated list of arguments to the userdb driver.
17100 Defaults to @samp{#f}.
17104 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
17105 Override fields from passwd.
17107 Defaults to @samp{""}.
17111 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
17112 Override fields from passwd.
17114 Defaults to @samp{()}.
17118 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
17119 PEM-formatted key file to use for the TLS negotiation
17121 Defaults to @samp{""}.
17125 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
17126 PEM-formatted certificate file to use for the TLS negotiation
17128 Defaults to @samp{""}.
17132 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
17133 CA certificates to use
17135 Defaults to @samp{""}.
17139 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
17140 Extra retriever parameters
17142 Defaults to @samp{()}.
17148 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
17149 What to do with retrieved messages.
17151 Available @code{getmail-destination-configuration} fields are:
17153 @deftypevr {@code{getmail-destination-configuration} parameter} string type
17154 The type of mail destination. Valid values include @samp{Maildir},
17155 @samp{Mboxrd} and @samp{MDA_external}.
17157 Defaults to @samp{unset}.
17161 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
17162 The path option for the mail destination. The behaviour depends on the
17165 Defaults to @samp{""}.
17169 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
17170 Extra destination parameters
17172 Defaults to @samp{()}.
17178 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
17181 Available @code{getmail-options-configuration} fields are:
17183 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
17184 If set to @samp{0}, getmail will only print warnings and errors. A
17185 value of @samp{1} means that messages will be printed about retrieving
17186 and deleting messages. If set to @samp{2}, getmail will print messages
17187 about each of it's actions.
17189 Defaults to @samp{1}.
17193 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
17194 If true, getmail will retrieve all available messages. Otherwise it
17195 will only retrieve messages it hasn't seen previously.
17197 Defaults to @samp{#t}.
17201 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
17202 If set to true, messages will be deleted from the server after
17203 retrieving and successfully delivering them. Otherwise, messages will
17204 be left on the server.
17206 Defaults to @samp{#f}.
17210 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
17211 Getmail will delete messages this number of days after seeing them, if
17212 they have not been delivered. This means messages will be left on the
17213 server this number of days after delivering them. A value of @samp{0}
17214 disabled this feature.
17216 Defaults to @samp{0}.
17220 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
17221 Delete messages larger than this of bytes after retrieving them, even if
17222 the delete and delete-after options are disabled. A value of @samp{0}
17223 disables this feature.
17225 Defaults to @samp{0}.
17229 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
17230 Retrieve messages totalling up to this number of bytes before closing
17231 the session with the server. A value of @samp{0} disables this feature.
17233 Defaults to @samp{0}.
17237 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
17238 Don't retrieve messages larger than this number of bytes. A value of
17239 @samp{0} disables this feature.
17241 Defaults to @samp{0}.
17245 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
17246 If true, getmail will add a Delivered-To header to messages.
17248 Defaults to @samp{#t}.
17252 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
17253 If set, getmail adds a Received header to the messages.
17255 Defaults to @samp{#t}.
17259 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
17260 Getmail will record a log of its actions to the named file. A value of
17261 @samp{""} disables this feature.
17263 Defaults to @samp{""}.
17267 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
17268 If true, getmail will record a log of its actions using the system
17271 Defaults to @samp{#t}.
17275 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
17276 If true, getmail will log information about messages not retrieved and
17277 the reason for not retrieving them, as well as starting and ending
17280 Defaults to @samp{#t}.
17284 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
17285 Extra options to include.
17287 Defaults to @samp{()}.
17295 @deftypevr {@code{getmail-configuration} parameter} list idle
17296 A list of mailboxes that getmail should wait on the server for new mail
17297 notifications. This depends on the server supporting the IDLE
17300 Defaults to @samp{()}.
17304 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
17305 Environment variables to set for getmail.
17307 Defaults to @samp{()}.
17311 @subsubheading Mail Aliases Service
17313 @cindex email aliases
17314 @cindex aliases, for email addresses
17316 @deffn {Scheme Variable} mail-aliases-service-type
17317 This is the type of the service which provides @code{/etc/aliases},
17318 specifying how to deliver mail to users on this system.
17321 (service mail-aliases-service-type
17322 '(("postmaster" "bob")
17323 ("bob" "bob@@example.com" "bob@@example2.com")))
17327 The configuration for a @code{mail-aliases-service-type} service is an
17328 association list denoting how to deliver mail that comes to this
17329 system. Each entry is of the form @code{(alias addresses ...)}, with
17330 @code{alias} specifying the local alias and @code{addresses} specifying
17331 where to deliver this user's mail.
17333 The aliases aren't required to exist as users on the local system. In
17334 the above example, there doesn't need to be a @code{postmaster} entry in
17335 the @code{operating-system}'s @code{user-accounts} in order to deliver
17336 the @code{postmaster} mail to @code{bob} (which subsequently would
17337 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
17339 @subsubheading GNU Mailutils IMAP4 Daemon
17340 @cindex GNU Mailutils IMAP4 Daemon
17342 @deffn {Scheme Variable} imap4d-service-type
17343 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
17344 mailutils, GNU Mailutils Manual}), whose value should be an
17345 @code{imap4d-configuration} object as in this example:
17348 (service imap4d-service-type
17349 (imap4d-configuration
17350 (config-file (local-file "imap4d.conf"))))
17354 @deftp {Data Type} imap4d-configuration
17355 Data type representing the configuration of @command{imap4d}.
17358 @item @code{package} (default: @code{mailutils})
17359 The package that provides @command{imap4d}.
17361 @item @code{config-file} (default: @code{%default-imap4d-config-file})
17362 File-like object of the configuration file to use, by default it will listen
17363 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
17364 Mailutils Manual}, for details.
17369 @node Messaging Services
17370 @subsection Messaging Services
17375 The @code{(gnu services messaging)} module provides Guix service
17376 definitions for messaging services: currently only Prosody is supported.
17378 @subsubheading Prosody Service
17380 @deffn {Scheme Variable} prosody-service-type
17381 This is the type for the @uref{https://prosody.im, Prosody XMPP
17382 communication server}. Its value must be a @code{prosody-configuration}
17383 record as in this example:
17386 (service prosody-service-type
17387 (prosody-configuration
17388 (modules-enabled (cons "groups" "mam" %default-modules-enabled))
17391 (int-component-configuration
17392 (hostname "conference.example.net")
17394 (mod-muc (mod-muc-configuration)))))
17397 (virtualhost-configuration
17398 (domain "example.net"))))))
17401 See below for details about @code{prosody-configuration}.
17405 By default, Prosody does not need much configuration. Only one
17406 @code{virtualhosts} field is needed: it specifies the domain you wish
17409 You can perform various sanity checks on the generated configuration
17410 with the @code{prosodyctl check} command.
17412 Prosodyctl will also help you to import certificates from the
17413 @code{letsencrypt} directory so that the @code{prosody} user can access
17414 them. See @url{https://prosody.im/doc/letsencrypt}.
17417 prosodyctl --root cert import /etc/letsencrypt/live
17420 The available configuration parameters follow. Each parameter
17421 definition is preceded by its type; for example, @samp{string-list foo}
17422 indicates that the @code{foo} parameter should be specified as a list of
17423 strings. Types starting with @code{maybe-} denote parameters that won't
17424 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
17426 There is also a way to specify the configuration as a string, if you
17427 have an old @code{prosody.cfg.lua} file that you want to port over from
17428 some other system; see the end for more details.
17430 The @code{file-object} type designates either a file-like object
17431 (@pxref{G-Expressions, file-like objects}) or a file name.
17433 @c The following documentation was initially generated by
17434 @c (generate-documentation) in (gnu services messaging). Manually maintained
17435 @c documentation is better, so we shouldn't hesitate to edit below as
17436 @c needed. However if the change you want to make to this documentation
17437 @c can be done in an automated way, it's probably easier to change
17438 @c (generate-documentation) than to make it below and have to deal with
17439 @c the churn as Prosody updates.
17441 Available @code{prosody-configuration} fields are:
17443 @deftypevr {@code{prosody-configuration} parameter} package prosody
17444 The Prosody package.
17447 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
17448 Location of the Prosody data storage directory. See
17449 @url{https://prosody.im/doc/configure}.
17450 Defaults to @samp{"/var/lib/prosody"}.
17453 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
17454 Additional plugin directories. They are searched in all the specified
17455 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
17456 Defaults to @samp{()}.
17459 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
17460 Every virtual host and component needs a certificate so that clients and
17461 servers can securely verify its identity. Prosody will automatically load
17462 certificates/keys from the directory specified here.
17463 Defaults to @samp{"/etc/prosody/certs"}.
17466 @deftypevr {@code{prosody-configuration} parameter} string-list admins
17467 This is a list of accounts that are admins for the server. Note that you
17468 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
17469 @url{https://prosody.im/doc/creating_accounts}.
17470 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
17471 Defaults to @samp{()}.
17474 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
17475 Enable use of libevent for better performance under high load. See
17476 @url{https://prosody.im/doc/libevent}.
17477 Defaults to @samp{#f}.
17480 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
17481 This is the list of modules Prosody will load on startup. It looks for
17482 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
17483 Documentation on modules can be found at:
17484 @url{https://prosody.im/doc/modules}.
17485 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
17488 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
17489 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
17490 should you want to disable them then add them to this list.
17491 Defaults to @samp{()}.
17494 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
17495 Path to a text file where the shared groups are defined. If this path is
17496 empty then @samp{mod_groups} does nothing. See
17497 @url{https://prosody.im/doc/modules/mod_groups}.
17498 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
17501 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
17502 Disable account creation by default, for security. See
17503 @url{https://prosody.im/doc/creating_accounts}.
17504 Defaults to @samp{#f}.
17507 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
17508 These are the SSL/TLS-related settings. Most of them are disabled so to
17509 use Prosody's defaults. If you do not completely understand these options, do
17510 not add them to your config, it is easy to lower the security of your server
17511 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
17513 Available @code{ssl-configuration} fields are:
17515 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
17516 This determines what handshake to use.
17519 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
17520 Path to your private key file.
17523 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
17524 Path to your certificate file.
17527 @deftypevr {@code{ssl-configuration} parameter} file-object capath
17528 Path to directory containing root certificates that you wish Prosody to
17529 trust when verifying the certificates of remote servers.
17530 Defaults to @samp{"/etc/ssl/certs"}.
17533 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
17534 Path to a file containing root certificates that you wish Prosody to trust.
17535 Similar to @code{capath} but with all certificates concatenated together.
17538 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
17539 A list of verification options (these mostly map to OpenSSL's
17540 @code{set_verify()} flags).
17543 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
17544 A list of general options relating to SSL/TLS. These map to OpenSSL's
17545 @code{set_options()}. For a full list of options available in LuaSec, see the
17549 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
17550 How long a chain of certificate authorities to check when looking for a
17551 trusted root certificate.
17554 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
17555 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
17556 clients, and in what order.
17559 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
17560 A path to a file containing parameters for Diffie-Hellman key exchange. You
17561 can create such a file with:
17562 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
17565 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
17566 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
17567 @samp{"secp384r1"}.
17570 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
17571 A list of "extra" verification options.
17574 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
17575 Password for encrypted private keys.
17580 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
17581 Whether to force all client-to-server connections to be encrypted or not.
17582 See @url{https://prosody.im/doc/modules/mod_tls}.
17583 Defaults to @samp{#f}.
17586 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
17587 Set of mechanisms that will never be offered. See
17588 @url{https://prosody.im/doc/modules/mod_saslauth}.
17589 Defaults to @samp{("DIGEST-MD5")}.
17592 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
17593 Whether to force all server-to-server connections to be encrypted or not.
17594 See @url{https://prosody.im/doc/modules/mod_tls}.
17595 Defaults to @samp{#f}.
17598 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
17599 Whether to require encryption and certificate authentication. This
17600 provides ideal security, but requires servers you communicate with to support
17601 encryption AND present valid, trusted certificates. See
17602 @url{https://prosody.im/doc/s2s#security}.
17603 Defaults to @samp{#f}.
17606 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
17607 Many servers don't support encryption or have invalid or self-signed
17608 certificates. You can list domains here that will not be required to
17609 authenticate using certificates. They will be authenticated using DNS. See
17610 @url{https://prosody.im/doc/s2s#security}.
17611 Defaults to @samp{()}.
17614 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
17615 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
17616 valid certificates for some domains by specifying a list here. See
17617 @url{https://prosody.im/doc/s2s#security}.
17618 Defaults to @samp{()}.
17621 @deftypevr {@code{prosody-configuration} parameter} string authentication
17622 Select the authentication backend to use. The default provider stores
17623 passwords in plaintext and uses Prosody's configured data storage to store the
17624 authentication data. If you do not trust your server please see
17625 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
17626 about using the hashed backend. See also
17627 @url{https://prosody.im/doc/authentication}
17628 Defaults to @samp{"internal_plain"}.
17631 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
17632 Set logging options. Advanced logging configuration is not yet supported
17633 by the Prosody service. See @url{https://prosody.im/doc/logging}.
17634 Defaults to @samp{"*syslog"}.
17637 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
17638 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
17639 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
17642 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
17643 Maximum allowed size of the HTTP body (in bytes).
17646 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
17647 Some modules expose their own URL in various ways. This URL is built
17648 from the protocol, host and port used. If Prosody sits behind a proxy, the
17649 public URL will be @code{http-external-url} instead. See
17650 @url{https://prosody.im/doc/http#external_url}.
17653 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
17654 A host in Prosody is a domain on which user accounts can be created. For
17655 example if you want your users to have addresses like
17656 @samp{"john.smith@@example.com"} then you need to add a host
17657 @samp{"example.com"}. All options in this list will apply only to this host.
17659 Note: the name "virtual" host is used in configuration to avoid confusion with
17660 the actual physical host that Prosody is installed on. A single Prosody
17661 instance can serve many domains, each one defined as a VirtualHost entry in
17662 Prosody's configuration. Conversely a server that hosts a single domain would
17663 have just one VirtualHost entry.
17665 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
17667 Available @code{virtualhost-configuration} fields are:
17669 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:
17670 @deftypevr {@code{virtualhost-configuration} parameter} string domain
17671 Domain you wish Prosody to serve.
17676 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
17677 Components are extra services on a server which are available to clients,
17678 usually on a subdomain of the main server (such as
17679 @samp{"mycomponent.example.com"}). Example components might be chatroom
17680 servers, user directories, or gateways to other protocols.
17682 Internal components are implemented with Prosody-specific plugins. To add an
17683 internal component, you simply fill the hostname field, and the plugin you wish
17684 to use for the component.
17686 See @url{https://prosody.im/doc/components}.
17687 Defaults to @samp{()}.
17689 Available @code{int-component-configuration} fields are:
17691 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:
17692 @deftypevr {@code{int-component-configuration} parameter} string hostname
17693 Hostname of the component.
17696 @deftypevr {@code{int-component-configuration} parameter} string plugin
17697 Plugin you wish to use for the component.
17700 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
17701 Multi-user chat (MUC) is Prosody's module for allowing you to create
17702 hosted chatrooms/conferences for XMPP users.
17704 General information on setting up and using multi-user chatrooms can be found
17705 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
17706 which you should read if you are new to XMPP chatrooms.
17708 See also @url{https://prosody.im/doc/modules/mod_muc}.
17710 Available @code{mod-muc-configuration} fields are:
17712 @deftypevr {@code{mod-muc-configuration} parameter} string name
17713 The name to return in service discovery responses.
17714 Defaults to @samp{"Prosody Chatrooms"}.
17717 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
17718 If @samp{#t}, this will only allow admins to create new chatrooms.
17719 Otherwise anyone can create a room. The value @samp{"local"} restricts room
17720 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
17721 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
17722 restricts to service administrators only.
17723 Defaults to @samp{#f}.
17726 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
17727 Maximum number of history messages that will be sent to the member that has
17728 just joined the room.
17729 Defaults to @samp{20}.
17736 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
17737 External components use XEP-0114, which most standalone components
17738 support. To add an external component, you simply fill the hostname field. See
17739 @url{https://prosody.im/doc/components}.
17740 Defaults to @samp{()}.
17742 Available @code{ext-component-configuration} fields are:
17744 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:
17745 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
17746 Password which the component will use to log in.
17749 @deftypevr {@code{ext-component-configuration} parameter} string hostname
17750 Hostname of the component.
17755 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
17756 Port(s) Prosody listens on for component connections.
17757 Defaults to @samp{(5347)}.
17760 @deftypevr {@code{prosody-configuration} parameter} string component-interface
17761 Interface Prosody listens on for component connections.
17762 Defaults to @samp{"127.0.0.1"}.
17765 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
17766 Raw content that will be added to the configuration file.
17769 It could be that you just want to get a @code{prosody.cfg.lua}
17770 up and running. In that case, you can pass an
17771 @code{opaque-prosody-configuration} record as the value of
17772 @code{prosody-service-type}. As its name indicates, an opaque configuration
17773 does not have easy reflective capabilities.
17774 Available @code{opaque-prosody-configuration} fields are:
17776 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
17777 The prosody package.
17780 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
17781 The contents of the @code{prosody.cfg.lua} to use.
17784 For example, if your @code{prosody.cfg.lua} is just the empty
17785 string, you could instantiate a prosody service like this:
17788 (service prosody-service-type
17789 (opaque-prosody-configuration
17790 (prosody.cfg.lua "")))
17793 @c end of Prosody auto-generated documentation
17795 @subsubheading BitlBee Service
17797 @cindex IRC (Internet Relay Chat)
17798 @cindex IRC gateway
17799 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
17800 interface to a variety of messaging protocols such as XMPP.
17802 @defvr {Scheme Variable} bitlbee-service-type
17803 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
17804 gateway daemon. Its value is a @code{bitlbee-configuration} (see
17807 To have BitlBee listen on port 6667 on localhost, add this line to your
17811 (service bitlbee-service-type)
17815 @deftp {Data Type} bitlbee-configuration
17816 This is the configuration for BitlBee, with the following fields:
17819 @item @code{interface} (default: @code{"127.0.0.1"})
17820 @itemx @code{port} (default: @code{6667})
17821 Listen on the network interface corresponding to the IP address
17822 specified in @var{interface}, on @var{port}.
17824 When @var{interface} is @code{127.0.0.1}, only local clients can
17825 connect; when it is @code{0.0.0.0}, connections can come from any
17826 networking interface.
17828 @item @code{package} (default: @code{bitlbee})
17829 The BitlBee package to use.
17831 @item @code{plugins} (default: @code{'()})
17832 List of plugin packages to use---e.g., @code{bitlbee-discord}.
17834 @item @code{extra-settings} (default: @code{""})
17835 Configuration snippet added as-is to the BitlBee configuration file.
17839 @subsubheading Quassel Service
17841 @cindex IRC (Internet Relay Chat)
17842 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
17843 meaning that one or more clients can attach to and detach from the
17846 @defvr {Scheme Variable} quassel-service-type
17847 This is the service type for the @url{https://quassel-irc.org/,Quassel}
17848 IRC backend daemon. Its value is a @code{quassel-configuration}
17852 @deftp {Data Type} quassel-configuration
17853 This is the configuration for Quassel, with the following fields:
17856 @item @code{quassel} (default: @code{quassel})
17857 The Quassel package to use.
17859 @item @code{interface} (default: @code{"::,0.0.0.0"})
17860 @item @code{port} (default: @code{4242})
17861 Listen on the network interface(s) corresponding to the IPv4 or IPv6
17862 interfaces specified in the comma delimited @var{interface}, on
17865 @item @code{loglevel} (default: @code{"Info"})
17866 The level of logging desired. Accepted values are Debug, Info, Warning
17871 @node Telephony Services
17872 @subsection Telephony Services
17874 @cindex Murmur (VoIP server)
17875 @cindex VoIP server
17876 This section describes how to set up and run a Murmur server. Murmur is
17877 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
17880 @deftp {Data Type} murmur-configuration
17881 The service type for the Murmur server. An example configuration can
17885 (service murmur-service-type
17886 (murmur-configuration
17888 "Welcome to this Mumble server running on Guix!")
17889 (cert-required? #t) ;disallow text password logins
17890 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
17891 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
17894 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
17895 password with the command that is printed during the activation phase.
17897 It is recommended to register a normal Mumble user account
17898 and grant it admin or moderator rights.
17899 You can use the @code{mumble} client to
17900 login as new normal user, register yourself, and log out.
17901 For the next step login with the name @code{SuperUser} use
17902 the @code{SuperUser} password that you set previously,
17903 and grant your newly registered mumble user administrator or moderator
17904 rights and create some channels.
17906 Available @code{murmur-configuration} fields are:
17909 @item @code{package} (default: @code{mumble})
17910 Package that contains @code{bin/murmurd}.
17912 @item @code{user} (default: @code{"murmur"})
17913 User who will run the Murmur server.
17915 @item @code{group} (default: @code{"murmur"})
17916 Group of the user who will run the murmur server.
17918 @item @code{port} (default: @code{64738})
17919 Port on which the server will listen.
17921 @item @code{welcome-text} (default: @code{""})
17922 Welcome text sent to clients when they connect.
17924 @item @code{server-password} (default: @code{""})
17925 Password the clients have to enter in order to connect.
17927 @item @code{max-users} (default: @code{100})
17928 Maximum of users that can be connected to the server at once.
17930 @item @code{max-user-bandwidth} (default: @code{#f})
17931 Maximum voice traffic a user can send per second.
17933 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
17934 File name of the sqlite database.
17935 The service's user will become the owner of the directory.
17937 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
17938 File name of the log file.
17939 The service's user will become the owner of the directory.
17941 @item @code{autoban-attempts} (default: @code{10})
17942 Maximum number of logins a user can make in @code{autoban-timeframe}
17943 without getting auto banned for @code{autoban-time}.
17945 @item @code{autoban-timeframe} (default: @code{120})
17946 Timeframe for autoban in seconds.
17948 @item @code{autoban-time} (default: @code{300})
17949 Amount of time in seconds for which a client gets banned
17950 when violating the autoban limits.
17952 @item @code{opus-threshold} (default: @code{100})
17953 Percentage of clients that need to support opus
17954 before switching over to opus audio codec.
17956 @item @code{channel-nesting-limit} (default: @code{10})
17957 How deep channels can be nested at maximum.
17959 @item @code{channelname-regex} (default: @code{#f})
17960 A string in form of a Qt regular expression that channel names must conform to.
17962 @item @code{username-regex} (default: @code{#f})
17963 A string in form of a Qt regular expression that user names must conform to.
17965 @item @code{text-message-length} (default: @code{5000})
17966 Maximum size in bytes that a user can send in one text chat message.
17968 @item @code{image-message-length} (default: @code{(* 128 1024)})
17969 Maximum size in bytes that a user can send in one image message.
17971 @item @code{cert-required?} (default: @code{#f})
17972 If it is set to @code{#t} clients that use weak password authentication
17973 will not be accepted. Users must have completed the certificate wizard to join.
17975 @item @code{remember-channel?} (default: @code{#f})
17976 Should murmur remember the last channel each user was in when they disconnected
17977 and put them into the remembered channel when they rejoin.
17979 @item @code{allow-html?} (default: @code{#f})
17980 Should html be allowed in text messages, user comments, and channel descriptions.
17982 @item @code{allow-ping?} (default: @code{#f})
17983 Setting to true exposes the current user count, the maximum user count, and
17984 the server's maximum bandwidth per client to unauthenticated users. In the
17985 Mumble client, this information is shown in the Connect dialog.
17987 Disabling this setting will prevent public listing of the server.
17989 @item @code{bonjour?} (default: @code{#f})
17990 Should the server advertise itself in the local network through the bonjour protocol.
17992 @item @code{send-version?} (default: @code{#f})
17993 Should the murmur server version be exposed in ping requests.
17995 @item @code{log-days} (default: @code{31})
17996 Murmur also stores logs in the database, which are accessible via RPC.
17997 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
17998 or -1 to disable logging to the database.
18000 @item @code{obfuscate-ips?} (default: @code{#t})
18001 Should logged ips be obfuscated to protect the privacy of users.
18003 @item @code{ssl-cert} (default: @code{#f})
18004 File name of the SSL/TLS certificate used for encrypted connections.
18007 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
18009 @item @code{ssl-key} (default: @code{#f})
18010 Filepath to the ssl private key used for encrypted connections.
18012 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
18015 @item @code{ssl-dh-params} (default: @code{#f})
18016 File name of a PEM-encoded file with Diffie-Hellman parameters
18017 for the SSL/TLS encryption. Alternatively you set it to
18018 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
18019 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
18021 @item @code{ssl-ciphers} (default: @code{#f})
18022 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
18025 This option is specified using
18026 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
18027 OpenSSL cipher list notation}.
18029 It is recommended that you try your cipher string using 'openssl ciphers <string>'
18030 before setting it here, to get a feel for which cipher suites you will get.
18031 After setting this option, it is recommend that you inspect your Murmur log
18032 to ensure that Murmur is using the cipher suites that you expected it to.
18034 Note: Changing this option may impact the backwards compatibility of your
18035 Murmur server, and can remove the ability for older Mumble clients to be able
18038 @item @code{public-registration} (default: @code{#f})
18039 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
18041 You can optionally register your server in the public server list that the
18042 @code{mumble} client shows on startup.
18043 You cannot register your server if you have set a @code{server-password},
18044 or set @code{allow-ping} to @code{#f}.
18046 It might take a few hours until it shows up in the public list.
18048 @item @code{file} (default: @code{#f})
18049 Optional alternative override for this configuration.
18053 @deftp {Data Type} murmur-public-registration-configuration
18054 Configuration for public registration of a murmur service.
18058 This is a display name for your server. Not to be confused with the hostname.
18060 @item @code{password}
18061 A password to identify your registration.
18062 Subsequent updates will need the same password. Don't lose your password.
18065 This should be a @code{http://} or @code{https://} link to your web
18068 @item @code{hostname} (default: @code{#f})
18069 By default your server will be listed by its IP address.
18070 If it is set your server will be linked by this host name instead.
18076 @node Monitoring Services
18077 @subsection Monitoring Services
18079 @subsubheading Tailon Service
18081 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
18082 viewing and searching log files.
18084 The following example will configure the service with default values.
18085 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
18088 (service tailon-service-type)
18091 The following example customises more of the Tailon configuration,
18092 adding @command{sed} to the list of allowed commands.
18095 (service tailon-service-type
18096 (tailon-configuration
18098 (tailon-configuration-file
18099 (allowed-commands '("tail" "grep" "awk" "sed"))))))
18103 @deftp {Data Type} tailon-configuration
18104 Data type representing the configuration of Tailon.
18105 This type has the following parameters:
18108 @item @code{config-file} (default: @code{(tailon-configuration-file)})
18109 The configuration file to use for Tailon. This can be set to a
18110 @dfn{tailon-configuration-file} record value, or any gexp
18111 (@pxref{G-Expressions}).
18113 For example, to instead use a local file, the @code{local-file} function
18117 (service tailon-service-type
18118 (tailon-configuration
18119 (config-file (local-file "./my-tailon.conf"))))
18122 @item @code{package} (default: @code{tailon})
18123 The tailon package to use.
18128 @deftp {Data Type} tailon-configuration-file
18129 Data type representing the configuration options for Tailon.
18130 This type has the following parameters:
18133 @item @code{files} (default: @code{(list "/var/log")})
18134 List of files to display. The list can include strings for a single file
18135 or directory, or a list, where the first item is the name of a
18136 subsection, and the remaining items are the files or directories in that
18139 @item @code{bind} (default: @code{"localhost:8080"})
18140 Address and port to which Tailon should bind on.
18142 @item @code{relative-root} (default: @code{#f})
18143 URL path to use for Tailon, set to @code{#f} to not use a path.
18145 @item @code{allow-transfers?} (default: @code{#t})
18146 Allow downloading the log files in the web interface.
18148 @item @code{follow-names?} (default: @code{#t})
18149 Allow tailing of not-yet existent files.
18151 @item @code{tail-lines} (default: @code{200})
18152 Number of lines to read initially from each file.
18154 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
18155 Commands to allow running. By default, @code{sed} is disabled.
18157 @item @code{debug?} (default: @code{#f})
18158 Set @code{debug?} to @code{#t} to show debug messages.
18160 @item @code{wrap-lines} (default: @code{#t})
18161 Initial line wrapping state in the web interface. Set to @code{#t} to
18162 initially wrap lines (the default), or to @code{#f} to initially not
18165 @item @code{http-auth} (default: @code{#f})
18166 HTTP authentication type to use. Set to @code{#f} to disable
18167 authentication (the default). Supported values are @code{"digest"} or
18170 @item @code{users} (default: @code{#f})
18171 If HTTP authentication is enabled (see @code{http-auth}), access will be
18172 restricted to the credentials provided here. To configure users, use a
18173 list of pairs, where the first element of the pair is the username, and
18174 the 2nd element of the pair is the password.
18177 (tailon-configuration-file
18178 (http-auth "basic")
18179 (users '(("user1" . "password1")
18180 ("user2" . "password2"))))
18187 @subsubheading Darkstat Service
18189 Darkstat is a packet sniffer that captures network traffic, calculates
18190 statistics about usage, and serves reports over HTTP.
18192 @defvar {Scheme Variable} darkstat-service-type
18193 This is the service type for the
18194 @uref{https://unix4lyfe.org/darkstat/, darkstat}
18195 service, its value must be a @code{darkstat-configuration} record as in
18199 (service darkstat-service-type
18200 (darkstat-configuration
18201 (interface "eno1")))
18205 @deftp {Data Type} darkstat-configuration
18206 Data type representing the configuration of @command{darkstat}.
18209 @item @code{package} (default: @code{darkstat})
18210 The darkstat package to use.
18212 @item @code{interface}
18213 Capture traffic on the specified network interface.
18215 @item @code{port} (default: @code{"667"})
18216 Bind the web interface to the specified port.
18218 @item @code{bind-address} (default: @code{"127.0.0.1"})
18219 Bind the web interface to the specified address.
18221 @item @code{base} (default: @code{"/"})
18222 Specify the path of the base URL. This can be useful if
18223 @command{darkstat} is accessed via a reverse proxy.
18228 @subsubheading Prometheus Node Exporter Service
18230 @cindex prometheus-node-exporter
18231 The Prometheus ``node exporter'' makes hardware and operating system statistics
18232 provided by the Linux kernel available for the Prometheus monitoring system.
18233 This service should be deployed on all physical nodes and virtual machines,
18234 where monitoring these statistics is desirable.
18236 @defvar {Scheme variable} prometheus-node-exporter-service-type
18237 This is the service type for the
18238 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
18239 service, its value must be a @code{prometheus-node-exporter-configuration}
18240 record as in this example:
18243 (service prometheus-node-exporter-service-type
18244 (prometheus-node-exporter-configuration
18245 (web-listen-address ":9100")))
18249 @deftp {Data Type} prometheus-node-exporter-configuration
18250 Data type representing the configuration of @command{node_exporter}.
18253 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
18254 The prometheus-node-exporter package to use.
18256 @item @code{web-listen-address} (default: @code{":9100"})
18257 Bind the web interface to the specified address.
18262 @subsubheading Zabbix server
18263 @cindex zabbix zabbix-server
18264 Zabbix provides monitoring metrics, among others network utilization, CPU load
18265 and disk space consumption:
18268 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
18269 @item Auto-discovery of servers and network devices and interfaces.
18270 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
18271 @item Distributed monitoring with centralized web administration.
18272 @item Native high performance agents.
18273 @item SLA, and ITIL KPI metrics on reporting.
18274 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
18275 @item Remote command execution through Zabbix proxies.
18278 @c %start of fragment
18280 Available @code{zabbix-server-configuration} fields are:
18282 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
18283 The zabbix-server package.
18287 @deftypevr {@code{zabbix-server-configuration} parameter} string user
18288 User who will run the Zabbix server.
18290 Defaults to @samp{"zabbix"}.
18294 @deftypevr {@code{zabbix-server-configuration} parameter} group group
18295 Group who will run the Zabbix server.
18297 Defaults to @samp{"zabbix"}.
18301 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
18302 Database host name.
18304 Defaults to @samp{"127.0.0.1"}.
18308 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
18311 Defaults to @samp{"zabbix"}.
18315 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
18318 Defaults to @samp{"zabbix"}.
18322 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
18323 Database password. Please, use @code{include-files} with
18324 @code{DBPassword=SECRET} inside a specified file instead.
18326 Defaults to @samp{""}.
18330 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
18333 Defaults to @samp{5432}.
18337 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
18338 Specifies where log messages are written to:
18342 @code{system} - syslog.
18345 @code{file} - file specified with @code{log-file} parameter.
18348 @code{console} - standard output.
18352 Defaults to @samp{""}.
18356 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
18357 Log file name for @code{log-type} @code{file} parameter.
18359 Defaults to @samp{"/var/log/zabbix/server.log"}.
18363 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
18366 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
18370 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
18371 The location of certificate authority (CA) files for SSL server
18372 certificate verification.
18374 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
18378 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
18379 Location of SSL client certificates.
18381 Defaults to @samp{"/etc/ssl/certs"}.
18385 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
18386 Extra options will be appended to Zabbix server configuration file.
18388 Defaults to @samp{""}.
18392 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
18393 You may include individual files or all files in a directory in the
18394 configuration file.
18396 Defaults to @samp{()}.
18400 @c %end of fragment
18402 @subsubheading Zabbix agent
18403 @cindex zabbix zabbix-agent
18405 Zabbix agent gathers information for Zabbix server.
18407 @c %start of fragment
18409 Available @code{zabbix-agent-configuration} fields are:
18411 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
18412 The zabbix-agent package.
18416 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
18417 User who will run the Zabbix agent.
18419 Defaults to @samp{"zabbix"}.
18423 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
18424 Group who will run the Zabbix agent.
18426 Defaults to @samp{"zabbix"}.
18430 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
18431 Unique, case sensitive hostname which is required for active checks and
18432 must match hostname as configured on the server.
18434 Defaults to @samp{"Zabbix server"}.
18438 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
18439 Specifies where log messages are written to:
18443 @code{system} - syslog.
18446 @code{file} - file specified with @code{log-file} parameter.
18449 @code{console} - standard output.
18453 Defaults to @samp{""}.
18457 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
18458 Log file name for @code{log-type} @code{file} parameter.
18460 Defaults to @samp{"/var/log/zabbix/agent.log"}.
18464 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
18467 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
18471 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
18472 List of IP addresses, optionally in CIDR notation, or hostnames of
18473 Zabbix servers and Zabbix proxies. Incoming connections will be
18474 accepted only from the hosts listed here.
18476 Defaults to @samp{("127.0.0.1")}.
18480 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
18481 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
18482 proxies for active checks. If port is not specified, default port is
18483 used. If this parameter is not specified, active checks are disabled.
18485 Defaults to @samp{("127.0.0.1")}.
18489 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
18490 Extra options will be appended to Zabbix server configuration file.
18492 Defaults to @samp{""}.
18496 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
18497 You may include individual files or all files in a directory in the
18498 configuration file.
18500 Defaults to @samp{()}.
18504 @c %end of fragment
18506 @subsubheading Zabbix front-end
18507 @cindex zabbix zabbix-front-end
18509 This service provides a WEB interface to Zabbix server.
18511 @c %start of fragment
18513 Available @code{zabbix-front-end-configuration} fields are:
18515 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
18516 NGINX configuration.
18520 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
18521 Database host name.
18523 Defaults to @samp{"localhost"}.
18527 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
18530 Defaults to @samp{5432}.
18534 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
18537 Defaults to @samp{"zabbix"}.
18541 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
18544 Defaults to @samp{"zabbix"}.
18548 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
18549 Database password. Please, use @code{db-secret-file} instead.
18551 Defaults to @samp{""}.
18555 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
18556 Secret file which will be appended to @file{zabbix.conf.php} file. This
18557 file contains credentials for use by Zabbix front-end. You are expected
18558 to create it manually.
18560 Defaults to @samp{""}.
18564 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
18565 Zabbix server hostname.
18567 Defaults to @samp{"localhost"}.
18571 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
18572 Zabbix server port.
18574 Defaults to @samp{10051}.
18579 @c %end of fragment
18581 @node Kerberos Services
18582 @subsection Kerberos Services
18585 The @code{(gnu services kerberos)} module provides services relating to
18586 the authentication protocol @dfn{Kerberos}.
18588 @subsubheading Krb5 Service
18590 Programs using a Kerberos client library normally
18591 expect a configuration file in @file{/etc/krb5.conf}.
18592 This service generates such a file from a definition provided in the
18593 operating system declaration.
18594 It does not cause any daemon to be started.
18596 No ``keytab'' files are provided by this service---you must explicitly create them.
18597 This service is known to work with the MIT client library, @code{mit-krb5}.
18598 Other implementations have not been tested.
18600 @defvr {Scheme Variable} krb5-service-type
18601 A service type for Kerberos 5 clients.
18605 Here is an example of its use:
18607 (service krb5-service-type
18608 (krb5-configuration
18609 (default-realm "EXAMPLE.COM")
18610 (allow-weak-crypto? #t)
18613 (name "EXAMPLE.COM")
18614 (admin-server "groucho.example.com")
18615 (kdc "karl.example.com"))
18618 (admin-server "kerb-admin.argrx.edu")
18619 (kdc "keys.argrx.edu"))))))
18623 This example provides a Kerberos@tie{}5 client configuration which:
18625 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
18626 of which have distinct administration servers and key distribution centers;
18627 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
18628 specified by clients;
18629 @item Accepts services which only support encryption types known to be weak.
18632 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
18633 Only the most commonly used ones are described here.
18634 For a full list, and more detailed explanation of each, see the MIT
18635 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
18639 @deftp {Data Type} krb5-realm
18640 @cindex realm, kerberos
18643 This field is a string identifying the name of the realm.
18644 A common convention is to use the fully qualified DNS name of your organization,
18645 converted to upper case.
18647 @item @code{admin-server}
18648 This field is a string identifying the host where the administration server is
18652 This field is a string identifying the key distribution center
18657 @deftp {Data Type} krb5-configuration
18660 @item @code{allow-weak-crypto?} (default: @code{#f})
18661 If this flag is @code{#t} then services which only offer encryption algorithms
18662 known to be weak will be accepted.
18664 @item @code{default-realm} (default: @code{#f})
18665 This field should be a string identifying the default Kerberos
18666 realm for the client.
18667 You should set this field to the name of your Kerberos realm.
18668 If this value is @code{#f}
18669 then a realm must be specified with every Kerberos principal when invoking programs
18670 such as @command{kinit}.
18672 @item @code{realms}
18673 This should be a non-empty list of @code{krb5-realm} objects, which clients may
18675 Normally, one of them will have a @code{name} field matching the @code{default-realm}
18681 @subsubheading PAM krb5 Service
18684 The @code{pam-krb5} service allows for login authentication and password
18685 management via Kerberos.
18686 You will need this service if you want PAM enabled applications to authenticate
18687 users using Kerberos.
18689 @defvr {Scheme Variable} pam-krb5-service-type
18690 A service type for the Kerberos 5 PAM module.
18693 @deftp {Data Type} pam-krb5-configuration
18694 Data type representing the configuration of the Kerberos 5 PAM module.
18695 This type has the following parameters:
18697 @item @code{pam-krb5} (default: @code{pam-krb5})
18698 The pam-krb5 package to use.
18700 @item @code{minimum-uid} (default: @code{1000})
18701 The smallest user ID for which Kerberos authentications should be attempted.
18702 Local accounts with lower values will silently fail to authenticate.
18707 @node LDAP Services
18708 @subsection LDAP Services
18710 @cindex nslcd, LDAP service
18712 The @code{(gnu services authentication)} module provides the
18713 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
18714 server. In addition to configuring the service itself, you may want to add
18715 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
18716 Switch} for detailed information.
18718 Here is a simple operating system declaration with a default configuration of
18719 the @code{nslcd-service-type} and a Name Service Switch configuration that
18720 consults the @code{ldap} name service last:
18723 (use-service-modules authentication)
18724 (use-modules (gnu system nss))
18730 (service nslcd-service-type)
18731 (service dhcp-client-service-type)
18733 (name-service-switch
18734 (let ((services (list (name-service (name "db"))
18735 (name-service (name "files"))
18736 (name-service (name "ldap")))))
18737 (name-service-switch
18738 (inherit %mdns-host-lookup-nss)
18739 (password services)
18742 (netgroup services)
18743 (gshadow services)))))
18746 @c %start of generated documentation for nslcd-configuration
18748 Available @code{nslcd-configuration} fields are:
18750 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
18751 The @code{nss-pam-ldapd} package to use.
18755 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
18756 The number of threads to start that can handle requests and perform LDAP
18757 queries. Each thread opens a separate connection to the LDAP server.
18758 The default is to start 5 threads.
18760 Defaults to @samp{disabled}.
18764 @deftypevr {@code{nslcd-configuration} parameter} string uid
18765 This specifies the user id with which the daemon should be run.
18767 Defaults to @samp{"nslcd"}.
18771 @deftypevr {@code{nslcd-configuration} parameter} string gid
18772 This specifies the group id with which the daemon should be run.
18774 Defaults to @samp{"nslcd"}.
18778 @deftypevr {@code{nslcd-configuration} parameter} log-option log
18779 This option controls the way logging is done via a list containing
18780 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
18781 or "syslog", or an absolute file name. The LEVEL argument is optional
18782 and specifies the log level. The log level may be one of the following
18783 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
18784 messages with the specified log level or higher are logged.
18786 Defaults to @samp{("/var/log/nslcd" info)}.
18790 @deftypevr {@code{nslcd-configuration} parameter} list uri
18791 The list of LDAP server URIs. Normally, only the first server will be
18792 used with the following servers as fall-back.
18794 Defaults to @samp{("ldap://localhost:389/")}.
18798 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
18799 The version of the LDAP protocol to use. The default is to use the
18800 maximum version supported by the LDAP library.
18802 Defaults to @samp{disabled}.
18806 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
18807 Specifies the distinguished name with which to bind to the directory
18808 server for lookups. The default is to bind anonymously.
18810 Defaults to @samp{disabled}.
18814 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
18815 Specifies the credentials with which to bind. This option is only
18816 applicable when used with binddn.
18818 Defaults to @samp{disabled}.
18822 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
18823 Specifies the distinguished name to use when the root user tries to
18824 modify a user's password using the PAM module.
18826 Defaults to @samp{disabled}.
18830 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
18831 Specifies the credentials with which to bind if the root user tries to
18832 change a user's password. This option is only applicable when used with
18835 Defaults to @samp{disabled}.
18839 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
18840 Specifies the SASL mechanism to be used when performing SASL
18843 Defaults to @samp{disabled}.
18847 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
18848 Specifies the SASL realm to be used when performing SASL authentication.
18850 Defaults to @samp{disabled}.
18854 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
18855 Specifies the authentication identity to be used when performing SASL
18858 Defaults to @samp{disabled}.
18862 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
18863 Specifies the authorization identity to be used when performing SASL
18866 Defaults to @samp{disabled}.
18870 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
18871 Determines whether the LDAP server host name should be canonicalised. If
18872 this is enabled the LDAP library will do a reverse host name lookup. By
18873 default, it is left up to the LDAP library whether this check is
18876 Defaults to @samp{disabled}.
18880 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
18881 Set the name for the GSS-API Kerberos credentials cache.
18883 Defaults to @samp{disabled}.
18887 @deftypevr {@code{nslcd-configuration} parameter} string base
18888 The directory search base.
18890 Defaults to @samp{"dc=example,dc=com"}.
18894 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
18895 Specifies the search scope (subtree, onelevel, base or children). The
18896 default scope is subtree; base scope is almost never useful for name
18897 service lookups; children scope is not supported on all servers.
18899 Defaults to @samp{(subtree)}.
18903 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
18904 Specifies the policy for dereferencing aliases. The default policy is
18905 to never dereference aliases.
18907 Defaults to @samp{disabled}.
18911 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
18912 Specifies whether automatic referral chasing should be enabled. The
18913 default behaviour is to chase referrals.
18915 Defaults to @samp{disabled}.
18919 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
18920 This option allows for custom attributes to be looked up instead of the
18921 default RFC 2307 attributes. It is a list of maps, each consisting of
18922 the name of a map, the RFC 2307 attribute to match and the query
18923 expression for the attribute as it is available in the directory.
18925 Defaults to @samp{()}.
18929 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
18930 A list of filters consisting of the name of a map to which the filter
18931 applies and an LDAP search filter expression.
18933 Defaults to @samp{()}.
18937 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
18938 Specifies the time limit in seconds to use when connecting to the
18939 directory server. The default value is 10 seconds.
18941 Defaults to @samp{disabled}.
18945 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
18946 Specifies the time limit (in seconds) to wait for a response from the
18947 LDAP server. A value of zero, which is the default, is to wait
18948 indefinitely for searches to be completed.
18950 Defaults to @samp{disabled}.
18954 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
18955 Specifies the period if inactivity (in seconds) after which the con‐
18956 nection to the LDAP server will be closed. The default is not to time
18959 Defaults to @samp{disabled}.
18963 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
18964 Specifies the number of seconds to sleep when connecting to all LDAP
18965 servers fails. By default one second is waited between the first
18966 failure and the first retry.
18968 Defaults to @samp{disabled}.
18972 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
18973 Specifies the time after which the LDAP server is considered to be
18974 permanently unavailable. Once this time is reached retries will be done
18975 only once per this time period. The default value is 10 seconds.
18977 Defaults to @samp{disabled}.
18981 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
18982 Specifies whether to use SSL/TLS or not (the default is not to). If
18983 'start-tls is specified then StartTLS is used rather than raw LDAP over
18986 Defaults to @samp{disabled}.
18990 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
18991 Specifies what checks to perform on a server-supplied certificate. The
18992 meaning of the values is described in the ldap.conf(5) manual page.
18994 Defaults to @samp{disabled}.
18998 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
18999 Specifies the directory containing X.509 certificates for peer authen‐
19000 tication. This parameter is ignored when using GnuTLS.
19002 Defaults to @samp{disabled}.
19006 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
19007 Specifies the path to the X.509 certificate for peer authentication.
19009 Defaults to @samp{disabled}.
19013 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
19014 Specifies the path to an entropy source. This parameter is ignored when
19017 Defaults to @samp{disabled}.
19021 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
19022 Specifies the ciphers to use for TLS as a string.
19024 Defaults to @samp{disabled}.
19028 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
19029 Specifies the path to the file containing the local certificate for
19030 client TLS authentication.
19032 Defaults to @samp{disabled}.
19036 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
19037 Specifies the path to the file containing the private key for client TLS
19040 Defaults to @samp{disabled}.
19044 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
19045 Set this to a number greater than 0 to request paged results from the
19046 LDAP server in accordance with RFC2696. The default (0) is to not
19047 request paged results.
19049 Defaults to @samp{disabled}.
19053 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
19054 This option prevents group membership lookups through LDAP for the
19055 specified users. Alternatively, the value 'all-local may be used. With
19056 that value nslcd builds a full list of non-LDAP users on startup.
19058 Defaults to @samp{disabled}.
19062 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
19063 This option ensures that LDAP users with a numeric user id lower than
19064 the specified value are ignored.
19066 Defaults to @samp{disabled}.
19070 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
19071 This option specifies an offset that is added to all LDAP numeric user
19072 ids. This can be used to avoid user id collisions with local users.
19074 Defaults to @samp{disabled}.
19078 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
19079 This option specifies an offset that is added to all LDAP numeric group
19080 ids. This can be used to avoid user id collisions with local groups.
19082 Defaults to @samp{disabled}.
19086 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
19087 If this option is set, the member attribute of a group may point to
19088 another group. Members of nested groups are also returned in the higher
19089 level group and parent groups are returned when finding groups for a
19090 specific user. The default is not to perform extra searches for nested
19093 Defaults to @samp{disabled}.
19097 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
19098 If this option is set, the group member list is not retrieved when
19099 looking up groups. Lookups for finding which groups a user belongs to
19100 will remain functional so the user will likely still get the correct
19101 groups assigned on login.
19103 Defaults to @samp{disabled}.
19107 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
19108 If this option is set, functions which cause all user/group entries to
19109 be loaded from the directory will not succeed in doing so. This can
19110 dramatically reduce LDAP server load in situations where there are a
19111 great number of users and/or groups. This option is not recommended for
19112 most configurations.
19114 Defaults to @samp{disabled}.
19118 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
19119 This option can be used to specify how user and group names are verified
19120 within the system. This pattern is used to check all user and group
19121 names that are requested and returned from LDAP.
19123 Defaults to @samp{disabled}.
19127 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
19128 This specifies whether or not to perform searches using case-insensitive
19129 matching. Enabling this could open up the system to authorization
19130 bypass vulnerabilities and introduce nscd cache poisoning
19131 vulnerabilities which allow denial of service.
19133 Defaults to @samp{disabled}.
19137 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
19138 This option specifies whether password policy controls are requested and
19139 handled from the LDAP server when performing user authentication.
19141 Defaults to @samp{disabled}.
19145 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
19146 By default nslcd performs an LDAP search with the user's credentials
19147 after BIND (authentication) to ensure that the BIND operation was
19148 successful. The default search is a simple check to see if the user's
19149 DN exists. A search filter can be specified that will be used instead.
19150 It should return at least one entry.
19152 Defaults to @samp{disabled}.
19156 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
19157 This option allows flexible fine tuning of the authorisation check that
19158 should be performed. The search filter specified is executed and if any
19159 entries match, access is granted, otherwise access is denied.
19161 Defaults to @samp{disabled}.
19165 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
19166 If this option is set password modification using pam_ldap will be
19167 denied and the specified message will be presented to the user instead.
19168 The message can be used to direct the user to an alternative means of
19169 changing their password.
19171 Defaults to @samp{disabled}.
19175 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
19176 List of pam service names for which LDAP authentication should suffice.
19178 Defaults to @samp{()}.
19182 @c %end of generated documentation for nslcd-configuration
19186 @subsection Web Services
19191 The @code{(gnu services web)} module provides the Apache HTTP Server,
19192 the nginx web server, and also a fastcgi wrapper daemon.
19194 @subsubheading Apache HTTP Server
19196 @deffn {Scheme Variable} httpd-service-type
19197 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
19198 (@dfn{httpd}). The value for this service type is a
19199 @code{httpd-configuration} record.
19201 A simple example configuration is given below.
19204 (service httpd-service-type
19205 (httpd-configuration
19208 (server-name "www.example.com")
19209 (document-root "/srv/http/www.example.com")))))
19212 Other services can also extend the @code{httpd-service-type} to add to
19216 (simple-service 'my-extra-server httpd-service-type
19220 (list (string-append
19221 "ServerName "www.example.com
19222 DocumentRoot \"/srv/http/www.example.com\"")))))
19226 The details for the @code{httpd-configuration}, @code{httpd-module},
19227 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
19230 @deffn {Data Type} httpd-configuration
19231 This data type represents the configuration for the httpd service.
19234 @item @code{package} (default: @code{httpd})
19235 The httpd package to use.
19237 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19238 The pid file used by the shepherd-service.
19240 @item @code{config} (default: @code{(httpd-config-file)})
19241 The configuration file to use with the httpd service. The default value
19242 is a @code{httpd-config-file} record, but this can also be a different
19243 G-expression that generates a file, for example a @code{plain-file}. A
19244 file outside of the store can also be specified through a string.
19249 @deffn {Data Type} httpd-module
19250 This data type represents a module for the httpd service.
19254 The name of the module.
19257 The file for the module. This can be relative to the httpd package being
19258 used, the absolute location of a file, or a G-expression for a file
19259 within the store, for example @code{(file-append mod-wsgi
19260 "/modules/mod_wsgi.so")}.
19265 @defvr {Scheme Variable} %default-httpd-modules
19266 A default list of @code{httpd-module} objects.
19269 @deffn {Data Type} httpd-config-file
19270 This data type represents a configuration file for the httpd service.
19273 @item @code{modules} (default: @code{%default-httpd-modules})
19274 The modules to load. Additional modules can be added here, or loaded by
19275 additional configuration.
19277 For example, in order to handle requests for PHP files, you can use Apache’s
19278 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
19281 (service httpd-service-type
19282 (httpd-configuration
19287 (name "proxy_module")
19288 (file "modules/mod_proxy.so"))
19290 (name "proxy_fcgi_module")
19291 (file "modules/mod_proxy_fcgi.so"))
19292 %default-httpd-modules))
19293 (extra-config (list "\
19294 <FilesMatch \\.php$>
19295 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
19296 </FilesMatch>"))))))
19297 (service php-fpm-service-type
19298 (php-fpm-configuration
19299 (socket "/var/run/php-fpm.sock")
19300 (socket-group "httpd")))
19303 @item @code{server-root} (default: @code{httpd})
19304 The @code{ServerRoot} in the configuration file, defaults to the httpd
19305 package. Directives including @code{Include} and @code{LoadModule} are
19306 taken as relative to the server root.
19308 @item @code{server-name} (default: @code{#f})
19309 The @code{ServerName} in the configuration file, used to specify the
19310 request scheme, hostname and port that the server uses to identify
19313 This doesn't need to be set in the server config, and can be specifyed
19314 in virtual hosts. The default is @code{#f} to not specify a
19317 @item @code{document-root} (default: @code{"/srv/http"})
19318 The @code{DocumentRoot} from which files will be served.
19320 @item @code{listen} (default: @code{'("80")})
19321 The list of values for the @code{Listen} directives in the config
19322 file. The value should be a list of strings, when each string can
19323 specify the port number to listen on, and optionally the IP address and
19326 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19327 The @code{PidFile} to use. This should match the @code{pid-file} set in
19328 the @code{httpd-configuration} so that the Shepherd service is
19329 configured correctly.
19331 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
19332 The @code{ErrorLog} to which the server will log errors.
19334 @item @code{user} (default: @code{"httpd"})
19335 The @code{User} which the server will answer requests as.
19337 @item @code{group} (default: @code{"httpd"})
19338 The @code{Group} which the server will answer requests as.
19340 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
19341 A flat list of strings and G-expressions which will be added to the end
19342 of the configuration file.
19344 Any values which the service is extended with will be appended to this
19350 @deffn {Data Type} httpd-virtualhost
19351 This data type represents a virtualhost configuration block for the httpd service.
19353 These should be added to the extra-config for the httpd-service.
19356 (simple-service 'my-extra-server httpd-service-type
19360 (list (string-append
19361 "ServerName "www.example.com
19362 DocumentRoot \"/srv/http/www.example.com\"")))))
19366 @item @code{addresses-and-ports}
19367 The addresses and ports for the @code{VirtualHost} directive.
19369 @item @code{contents}
19370 The contents of the @code{VirtualHost} directive, this should be a list
19371 of strings and G-expressions.
19376 @subsubheading NGINX
19378 @deffn {Scheme Variable} nginx-service-type
19379 Service type for the @uref{https://nginx.org/,NGinx} web server. The
19380 value for this service type is a @code{<nginx-configuration>} record.
19382 A simple example configuration is given below.
19385 (service nginx-service-type
19386 (nginx-configuration
19388 (list (nginx-server-configuration
19389 (server-name '("www.example.com"))
19390 (root "/srv/http/www.example.com"))))))
19393 In addition to adding server blocks to the service configuration
19394 directly, this service can be extended by other services to add server
19395 blocks, as in this example:
19398 (simple-service 'my-extra-server nginx-service-type
19399 (list (nginx-server-configuration
19400 (root "/srv/http/extra-website")
19401 (try-files (list "$uri" "$uri/index.html")))))
19405 At startup, @command{nginx} has not yet read its configuration file, so
19406 it uses a default file to log error messages. If it fails to load its
19407 configuration file, that is where error messages are logged. After the
19408 configuration file is loaded, the default error log file changes as per
19409 configuration. In our case, startup error messages can be found in
19410 @file{/var/run/nginx/logs/error.log}, and after configuration in
19411 @file{/var/log/nginx/error.log}. The second location can be changed
19412 with the @var{log-directory} configuration option.
19414 @deffn {Data Type} nginx-configuration
19415 This data type represents the configuration for NGinx. Some
19416 configuration can be done through this and the other provided record
19417 types, or alternatively, a config file can be provided.
19420 @item @code{nginx} (default: @code{nginx})
19421 The nginx package to use.
19423 @item @code{log-directory} (default: @code{"/var/log/nginx"})
19424 The directory to which NGinx will write log files.
19426 @item @code{run-directory} (default: @code{"/var/run/nginx"})
19427 The directory in which NGinx will create a pid file, and write temporary
19430 @item @code{server-blocks} (default: @code{'()})
19431 A list of @dfn{server blocks} to create in the generated configuration
19432 file, the elements should be of type
19433 @code{<nginx-server-configuration>}.
19435 The following example would setup NGinx to serve @code{www.example.com}
19436 from the @code{/srv/http/www.example.com} directory, without using
19439 (service nginx-service-type
19440 (nginx-configuration
19442 (list (nginx-server-configuration
19443 (server-name '("www.example.com"))
19444 (root "/srv/http/www.example.com"))))))
19447 @item @code{upstream-blocks} (default: @code{'()})
19448 A list of @dfn{upstream blocks} to create in the generated configuration
19449 file, the elements should be of type
19450 @code{<nginx-upstream-configuration>}.
19452 Configuring upstreams through the @code{upstream-blocks} can be useful
19453 when combined with @code{locations} in the
19454 @code{<nginx-server-configuration>} records. The following example
19455 creates a server configuration with one location configuration, that
19456 will proxy requests to a upstream configuration, which will handle
19457 requests with two servers.
19462 (nginx-configuration
19464 (list (nginx-server-configuration
19465 (server-name '("www.example.com"))
19466 (root "/srv/http/www.example.com")
19469 (nginx-location-configuration
19471 (body '("proxy_pass http://server-proxy;"))))))))
19473 (list (nginx-upstream-configuration
19474 (name "server-proxy")
19475 (servers (list "server1.example.com"
19476 "server2.example.com")))))))
19479 @item @code{file} (default: @code{#f})
19480 If a configuration @var{file} is provided, this will be used, rather than
19481 generating a configuration file from the provided @code{log-directory},
19482 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
19483 proper operation, these arguments should match what is in @var{file} to ensure
19484 that the directories are created when the service is activated.
19486 This can be useful if you have an existing configuration file, or it's
19487 not possible to do what is required through the other parts of the
19488 nginx-configuration record.
19490 @item @code{server-names-hash-bucket-size} (default: @code{#f})
19491 Bucket size for the server names hash tables, defaults to @code{#f} to
19492 use the size of the processors cache line.
19494 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
19495 Maximum bucket size for the server names hash tables.
19497 @item @code{extra-content} (default: @code{""})
19498 Extra content for the @code{http} block. Should be string or a string
19499 valued G-expression.
19504 @deftp {Data Type} nginx-server-configuration
19505 Data type representing the configuration of an nginx server block.
19506 This type has the following parameters:
19509 @item @code{listen} (default: @code{'("80" "443 ssl")})
19510 Each @code{listen} directive sets the address and port for IP, or the
19511 path for a UNIX-domain socket on which the server will accept requests.
19512 Both address and port, or only address or only port can be specified.
19513 An address may also be a hostname, for example:
19516 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
19519 @item @code{server-name} (default: @code{(list 'default)})
19520 A list of server names this server represents. @code{'default} represents the
19521 default server for connections matching no other server.
19523 @item @code{root} (default: @code{"/srv/http"})
19524 Root of the website nginx will serve.
19526 @item @code{locations} (default: @code{'()})
19527 A list of @dfn{nginx-location-configuration} or
19528 @dfn{nginx-named-location-configuration} records to use within this
19531 @item @code{index} (default: @code{(list "index.html")})
19532 Index files to look for when clients ask for a directory. If it cannot be found,
19533 Nginx will send the list of files in the directory.
19535 @item @code{try-files} (default: @code{'()})
19536 A list of files whose existence is checked in the specified order.
19537 @code{nginx} will use the first file it finds to process the request.
19539 @item @code{ssl-certificate} (default: @code{#f})
19540 Where to find the certificate for secure connections. Set it to @code{#f} if
19541 you don't have a certificate or you don't want to use HTTPS.
19543 @item @code{ssl-certificate-key} (default: @code{#f})
19544 Where to find the private key for secure connections. Set it to @code{#f} if
19545 you don't have a key or you don't want to use HTTPS.
19547 @item @code{server-tokens?} (default: @code{#f})
19548 Whether the server should add its configuration to response.
19550 @item @code{raw-content} (default: @code{'()})
19551 A list of raw lines added to the server block.
19556 @deftp {Data Type} nginx-upstream-configuration
19557 Data type representing the configuration of an nginx @code{upstream}
19558 block. This type has the following parameters:
19562 Name for this group of servers.
19564 @item @code{servers}
19565 Specify the addresses of the servers in the group. The address can be
19566 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
19567 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
19568 prefix @samp{unix:}. For addresses using an IP address or domain name,
19569 the default port is 80, and a different port can be specified
19575 @deftp {Data Type} nginx-location-configuration
19576 Data type representing the configuration of an nginx @code{location}
19577 block. This type has the following parameters:
19581 URI which this location block matches.
19583 @anchor{nginx-location-configuration body}
19585 Body of the location block, specified as a list of strings. This can contain
19587 configuration directives. For example, to pass requests to a upstream
19588 server group defined using an @code{nginx-upstream-configuration} block,
19589 the following directive would be specified in the body @samp{(list "proxy_pass
19590 http://upstream-name;")}.
19595 @deftp {Data Type} nginx-named-location-configuration
19596 Data type representing the configuration of an nginx named location
19597 block. Named location blocks are used for request redirection, and not
19598 used for regular request processing. This type has the following
19603 Name to identify this location block.
19606 @xref{nginx-location-configuration body}, as the body for named location
19607 blocks can be used in a similar way to the
19608 @code{nginx-location-configuration body}. One restriction is that the
19609 body of a named location block cannot contain location blocks.
19614 @subsubheading Varnish Cache
19616 Varnish is a fast cache server that sits in between web applications
19617 and end users. It proxies requests from clients and caches the
19618 accessed URLs such that multiple requests for the same resource only
19619 creates one request to the back-end.
19621 @defvr {Scheme Variable} varnish-service-type
19622 Service type for the Varnish daemon.
19625 @deftp {Data Type} varnish-configuration
19626 Data type representing the @code{varnish} service configuration.
19627 This type has the following parameters:
19630 @item @code{package} (default: @code{varnish})
19631 The Varnish package to use.
19633 @item @code{name} (default: @code{"default"})
19634 A name for this Varnish instance. Varnish will create a directory in
19635 @file{/var/varnish/} with this name and keep temporary files there. If
19636 the name starts with a forward slash, it is interpreted as an absolute
19639 Pass the @code{-n} argument to other Varnish programs to connect to the
19640 named instance, e.g.@: @command{varnishncsa -n default}.
19642 @item @code{backend} (default: @code{"localhost:8080"})
19643 The backend to use. This option has no effect if @code{vcl} is set.
19645 @item @code{vcl} (default: #f)
19646 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
19647 is @code{#f}, Varnish will proxy @code{backend} using the default
19648 configuration. Otherwise this must be a file-like object with valid
19651 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
19652 For example, to mirror @url{http://www.gnu.org,www.gnu.org} with VCL you
19653 can do something along these lines:
19656 (define %gnu-mirror
19660 backend gnu @{ .host = "www.gnu.org"; @}"))
19664 (services (cons (service varnish-service-type
19665 (varnish-configuration
19667 (vcl %gnu-mirror)))
19671 The configuration of an already running Varnish instance can be inspected
19672 and changed using the @command{varnishadm} program.
19674 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
19675 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
19676 comprehensive documentation on Varnish and its configuration language.
19678 @item @code{listen} (default: @code{'("localhost:80")})
19679 List of addresses Varnish will listen on.
19681 @item @code{storage} (default: @code{'("malloc,128m")})
19682 List of storage backends that will be available in VCL.
19684 @item @code{parameters} (default: @code{'()})
19685 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
19687 @item @code{extra-options} (default: @code{'()})
19688 Additional arguments to pass to the @command{varnishd} process.
19693 @subsubheading Patchwork
19695 Patchwork is a patch tracking system. It can collect patches sent to a
19696 mailing list, and display them in a web interface.
19698 @defvr {Scheme Variable} patchwork-service-type
19699 Service type for Patchwork.
19702 The following example is an example of a minimal service for Patchwork, for
19703 the @code{patchwork.example.com} domain.
19706 (service patchwork-service-type
19707 (patchwork-configuration
19708 (domain "patchwork.example.com")
19710 (patchwork-settings-module
19711 (allowed-hosts (list domain))
19712 (default-from-email "patchwork@@patchwork.example.com")))
19713 (getmail-retriever-config
19714 (getmail-retriever-configuration
19715 (type "SimpleIMAPSSLRetriever")
19716 (server "imap.example.com")
19718 (username "patchwork")
19720 (list (file-append coreutils "/bin/cat")
19721 "/etc/getmail-patchwork-imap-password"))
19723 '((mailboxes . ("Patches"))))))))
19727 There are three records for configuring the Patchwork service. The
19728 @code{<patchwork-configuration>} relates to the configuration for Patchwork
19729 within the HTTPD service.
19731 The @code{settings-module} field within the @code{<patchwork-configuration>}
19732 record can be populated with the @code{<patchwork-settings-module>} record,
19733 which describes a settings module that is generated within the Guix store.
19735 For the @code{database-configuration} field within the
19736 @code{<patchwork-settings-module>}, the
19737 @code{<patchwork-database-configuration>} must be used.
19739 @deftp {Data Type} patchwork-configuration
19740 Data type representing the Patchwork service configuration. This type has the
19741 following parameters:
19744 @item @code{patchwork} (default: @code{patchwork})
19745 The Patchwork package to use.
19747 @item @code{domain}
19748 The domain to use for Patchwork, this is used in the HTTPD service virtual
19751 @item @code{settings-module}
19752 The settings module to use for Patchwork. As a Django application, Patchwork
19753 is configured with a Python module containing the settings. This can either be
19754 an instance of the @code{<patchwork-settings-module>} record, any other record
19755 that represents the settings in the store, or a directory outside of the
19758 @item @code{static-path} (default: @code{"/static/"})
19759 The path under which the HTTPD service should serve the static files.
19761 @item @code{getmail-retriever-config}
19762 The getmail-retriever-configuration record value to use with
19763 Patchwork. Getmail will be configured with this value, the messages will be
19764 delivered to Patchwork.
19769 @deftp {Data Type} patchwork-settings-module
19770 Data type representing a settings module for Patchwork. Some of these
19771 settings relate directly to Patchwork, but others relate to Django, the web
19772 framework used by Patchwork, or the Django Rest Framework library. This type
19773 has the following parameters:
19776 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
19777 The database connection settings used for Patchwork. See the
19778 @code{<patchwork-database-configuration>} record type for more information.
19780 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
19781 Patchwork, as a Django web application uses a secret key for cryptographically
19782 signing values. This file should contain a unique unpredictable value.
19784 If this file does not exist, it will be created and populated with a random
19785 value by the patchwork-setup shepherd service.
19787 This setting relates to Django.
19789 @item @code{allowed-hosts}
19790 A list of valid hosts for this Patchwork service. This should at least include
19791 the domain specified in the @code{<patchwork-configuration>} record.
19793 This is a Django setting.
19795 @item @code{default-from-email}
19796 The email address from which Patchwork should send email by default.
19798 This is a Patchwork setting.
19800 @item @code{static-url} (default: @code{#f})
19801 The URL to use when serving static assets. It can be part of a URL, or a full
19802 URL, but must end in a @code{/}.
19804 If the default value is used, the @code{static-path} value from the
19805 @code{<patchwork-configuration>} record will be used.
19807 This is a Django setting.
19809 @item @code{admins} (default: @code{'()})
19810 Email addresses to send the details of errors that occur. Each value should
19811 be a list containing two elements, the name and then the email address.
19813 This is a Django setting.
19815 @item @code{debug?} (default: @code{#f})
19816 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
19817 messages will be shown.
19819 This is a Django setting.
19821 @item @code{enable-rest-api?} (default: @code{#t})
19822 Whether to enable the Patchwork REST API.
19824 This is a Patchwork setting.
19826 @item @code{enable-xmlrpc?} (default: @code{#t})
19827 Whether to enable the XML RPC API.
19829 This is a Patchwork setting.
19831 @item @code{force-https-links?} (default: @code{#t})
19832 Whether to use HTTPS links on Patchwork pages.
19834 This is a Patchwork setting.
19836 @item @code{extra-settings} (default: @code{""})
19837 Extra code to place at the end of the Patchwork settings module.
19842 @deftp {Data Type} patchwork-database-configuration
19843 Data type representing the database configuration for Patchwork.
19846 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
19847 The database engine to use.
19849 @item @code{name} (default: @code{"patchwork"})
19850 The name of the database to use.
19852 @item @code{user} (default: @code{"httpd"})
19853 The user to connect to the database as.
19855 @item @code{password} (default: @code{""})
19856 The password to use when connecting to the database.
19858 @item @code{host} (default: @code{""})
19859 The host to make the database connection to.
19861 @item @code{port} (default: @code{""})
19862 The port on which to connect to the database.
19867 @subsubheading FastCGI
19870 FastCGI is an interface between the front-end and the back-end of a web
19871 service. It is a somewhat legacy facility; new web services should
19872 generally just talk HTTP between the front-end and the back-end.
19873 However there are a number of back-end services such as PHP or the
19874 optimized HTTP Git repository access that use FastCGI, so we have
19875 support for it in Guix.
19877 To use FastCGI, you configure the front-end web server (e.g., nginx) to
19878 dispatch some subset of its requests to the fastcgi backend, which
19879 listens on a local TCP or UNIX socket. There is an intermediary
19880 @code{fcgiwrap} program that sits between the actual backend process and
19881 the web server. The front-end indicates which backend program to run,
19882 passing that information to the @code{fcgiwrap} process.
19884 @defvr {Scheme Variable} fcgiwrap-service-type
19885 A service type for the @code{fcgiwrap} FastCGI proxy.
19888 @deftp {Data Type} fcgiwrap-configuration
19889 Data type representing the configuration of the @code{fcgiwrap} service.
19890 This type has the following parameters:
19892 @item @code{package} (default: @code{fcgiwrap})
19893 The fcgiwrap package to use.
19895 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
19896 The socket on which the @code{fcgiwrap} process should listen, as a
19897 string. Valid @var{socket} values include
19898 @code{unix:@var{/path/to/unix/socket}},
19899 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
19900 @code{tcp6:[@var{ipv6_addr}]:port}.
19902 @item @code{user} (default: @code{fcgiwrap})
19903 @itemx @code{group} (default: @code{fcgiwrap})
19904 The user and group names, as strings, under which to run the
19905 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
19906 the user asks for the specific user or group names @code{fcgiwrap} that
19907 the corresponding user and/or group is present on the system.
19909 It is possible to configure a FastCGI-backed web service to pass HTTP
19910 authentication information from the front-end to the back-end, and to
19911 allow @code{fcgiwrap} to run the back-end process as a corresponding
19912 local user. To enable this capability on the back-end., run
19913 @code{fcgiwrap} as the @code{root} user and group. Note that this
19914 capability also has to be configured on the front-end as well.
19919 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
19920 with some additional features useful for sites of any size.
19922 These features include:
19924 @item Adaptive process spawning
19925 @item Basic statistics (similar to Apache's mod_status)
19926 @item Advanced process management with graceful stop/start
19927 @item Ability to start workers with different uid/gid/chroot/environment
19928 and different php.ini (replaces safe_mode)
19929 @item Stdout & stderr logging
19930 @item Emergency restart in case of accidental opcode cache destruction
19931 @item Accelerated upload support
19932 @item Support for a "slowlog"
19933 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
19934 a special function to finish request & flush all data while continuing to do
19935 something time-consuming (video converting, stats processing, etc.)
19937 ...@: and much more.
19939 @defvr {Scheme Variable} php-fpm-service-type
19940 A Service type for @code{php-fpm}.
19943 @deftp {Data Type} php-fpm-configuration
19944 Data Type for php-fpm service configuration.
19946 @item @code{php} (default: @code{php})
19947 The php package to use.
19948 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
19949 The address on which to accept FastCGI requests. Valid syntaxes are:
19951 @item @code{"ip.add.re.ss:port"}
19952 Listen on a TCP socket to a specific address on a specific port.
19953 @item @code{"port"}
19954 Listen on a TCP socket to all addresses on a specific port.
19955 @item @code{"/path/to/unix/socket"}
19956 Listen on a unix socket.
19959 @item @code{user} (default: @code{php-fpm})
19960 User who will own the php worker processes.
19961 @item @code{group} (default: @code{php-fpm})
19962 Group of the worker processes.
19963 @item @code{socket-user} (default: @code{php-fpm})
19964 User who can speak to the php-fpm socket.
19965 @item @code{socket-group} (default: @code{php-fpm})
19966 Group that can speak to the php-fpm socket.
19967 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
19968 The process id of the php-fpm process is written to this file
19969 once the service has started.
19970 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
19971 Log for the php-fpm master process.
19972 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
19973 Detailed settings for the php-fpm process manager.
19976 @item @code{<php-fpm-dynamic-process-manager-configuration>}
19977 @item @code{<php-fpm-static-process-manager-configuration>}
19978 @item @code{<php-fpm-on-demand-process-manager-configuration>}
19980 @item @code{display-errors} (default @code{#f})
19981 Determines whether php errors and warning should be sent to clients
19982 and displayed in their browsers.
19983 This is useful for local php development, but a security risk for public sites,
19984 as error messages can reveal passwords and personal data.
19985 @item @code{timezone} (default @code{#f})
19986 Specifies @code{php_admin_value[date.timezone]} parameter.
19987 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
19988 This file will log the @code{stderr} outputs of php worker processes.
19989 Can be set to @code{#f} to disable logging.
19990 @item @code{file} (default @code{#f})
19991 An optional override of the whole configuration.
19992 You can use the @code{mixed-text-file} function or an absolute filepath for it.
19996 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
19997 Data Type for the @code{dynamic} php-fpm process manager. With the
19998 @code{dynamic} process manager, spare worker processes are kept around
19999 based on it's configured limits.
20001 @item @code{max-children} (default: @code{5})
20002 Maximum of worker processes.
20003 @item @code{start-servers} (default: @code{2})
20004 How many worker processes should be started on start-up.
20005 @item @code{min-spare-servers} (default: @code{1})
20006 How many spare worker processes should be kept around at minimum.
20007 @item @code{max-spare-servers} (default: @code{3})
20008 How many spare worker processes should be kept around at maximum.
20012 @deftp {Data type} php-fpm-static-process-manager-configuration
20013 Data Type for the @code{static} php-fpm process manager. With the
20014 @code{static} process manager, an unchanging number of worker processes
20017 @item @code{max-children} (default: @code{5})
20018 Maximum of worker processes.
20022 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
20023 Data Type for the @code{on-demand} php-fpm process manager. With the
20024 @code{on-demand} process manager, worker processes are only created as
20027 @item @code{max-children} (default: @code{5})
20028 Maximum of worker processes.
20029 @item @code{process-idle-timeout} (default: @code{10})
20030 The time in seconds after which a process with no requests is killed.
20035 @deffn {Scheme Procedure} nginx-php-fpm-location @
20036 [#:nginx-package nginx] @
20037 [socket (string-append "/var/run/php" @
20038 (version-major (package-version php)) @
20040 A helper function to quickly add php to an @code{nginx-server-configuration}.
20043 A simple services setup for nginx with php can look like this:
20045 (services (cons* (service dhcp-client-service-type)
20046 (service php-fpm-service-type)
20047 (service nginx-service-type
20048 (nginx-server-configuration
20049 (server-name '("example.com"))
20050 (root "/srv/http/")
20052 (list (nginx-php-location)))
20054 (ssl-certificate #f)
20055 (ssl-certificate-key #f)))
20059 @cindex cat-avatar-generator
20060 The cat avatar generator is a simple service to demonstrate the use of php-fpm
20061 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
20062 the hash of a user's email address.
20064 @deffn {Scheme Procedure} cat-avatar-generator-service @
20065 [#:cache-dir "/var/cache/cat-avatar-generator"] @
20066 [#:package cat-avatar-generator] @
20067 [#:configuration (nginx-server-configuration)]
20068 Returns an nginx-server-configuration that inherits @code{configuration}. It
20069 extends the nginx configuration to add a server block that serves @code{package},
20070 a version of cat-avatar-generator. During execution, cat-avatar-generator will
20071 be able to use @code{cache-dir} as its cache directory.
20074 A simple setup for cat-avatar-generator can look like this:
20076 (services (cons* (cat-avatar-generator-service
20078 (nginx-server-configuration
20079 (server-name '("example.com"))))
20084 @subsubheading Hpcguix-web
20086 @cindex hpcguix-web
20087 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
20088 program is a customizable web interface to browse Guix packages,
20089 initially designed for users of high-performance computing (HPC)
20092 @defvr {Scheme Variable} hpcguix-web-service-type
20093 The service type for @code{hpcguix-web}.
20096 @deftp {Data Type} hpcguix-web-configuration
20097 Data type for the hpcguix-web service configuration.
20101 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
20102 configuration. The main items available in this spec are:
20105 @item @code{title-prefix} (default: @code{"hpcguix | "})
20106 The page title prefix.
20108 @item @code{guix-command} (default: @code{"guix"})
20109 The @command{guix} command.
20111 @item @code{package-filter-proc} (default: @code{(const #t)})
20112 A procedure specifying how to filter packages that are displayed.
20114 @item @code{package-page-extension-proc} (default: @code{(const '())})
20115 Extension package for @code{hpcguix-web}.
20117 @item @code{menu} (default: @code{'()})
20118 Additional entry in page @code{menu}.
20120 @item @code{channels} (default: @code{%default-channels})
20121 List of channels from which the package list is built (@pxref{Channels}).
20123 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
20124 The expiration time, in seconds, after which the package list is rebuilt from
20125 the latest instances of the given channels.
20128 See the hpcguix-web repository for a
20129 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
20132 @item @code{package} (default: @code{hpcguix-web})
20133 The hpcguix-web package to use.
20137 A typical hpcguix-web service declaration looks like this:
20140 (service hpcguix-web-service-type
20141 (hpcguix-web-configuration
20143 #~(define site-config
20144 (hpcweb-configuration
20145 (title-prefix "Guix-HPC - ")
20146 (menu '(("/about" "ABOUT"))))))))
20150 The hpcguix-web service periodically updates the package list it publishes by
20151 pulling channels from Git. To that end, it needs to access X.509 certificates
20152 so that it can authenticate Git servers when communicating over HTTPS, and it
20153 assumes that @file{/etc/ssl/certs} contains those certificates.
20155 Thus, make sure to add @code{nss-certs} or another certificate package to the
20156 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
20157 more information on X.509 certificates.
20160 @node Certificate Services
20161 @subsection Certificate Services
20164 @cindex HTTP, HTTPS
20165 @cindex Let's Encrypt
20166 @cindex TLS certificates
20167 The @code{(gnu services certbot)} module provides a service to
20168 automatically obtain a valid TLS certificate from the Let's Encrypt
20169 certificate authority. These certificates can then be used to serve
20170 content securely over HTTPS or other TLS-based protocols, with the
20171 knowledge that the client will be able to verify the server's
20174 @url{https://letsencrypt.org/, Let's Encrypt} provides the
20175 @code{certbot} tool to automate the certification process. This tool
20176 first securely generates a key on the server. It then makes a request
20177 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
20178 checks that the request originates from the host in question by using a
20179 challenge-response protocol, requiring the server to provide its
20180 response over HTTP. If that protocol completes successfully, the CA
20181 signs the key, resulting in a certificate. That certificate is valid
20182 for a limited period of time, and therefore to continue to provide TLS
20183 services, the server needs to periodically ask the CA to renew its
20186 The certbot service automates this process: the initial key
20187 generation, the initial certification request to the Let's Encrypt
20188 service, the web server challenge/response integration, writing the
20189 certificate to disk, the automated periodic renewals, and the deployment
20190 tasks associated with the renewal (e.g.@: reloading services, copying keys
20191 with different permissions).
20193 Certbot is run twice a day, at a random minute within the hour. It
20194 won't do anything until your certificates are due for renewal or
20195 revoked, but running it regularly would give your service a chance of
20196 staying online in case a Let's Encrypt-initiated revocation happened for
20199 By using this service, you agree to the ACME Subscriber Agreement, which
20200 can be found there:
20201 @url{https://acme-v01.api.letsencrypt.org/directory}.
20203 @defvr {Scheme Variable} certbot-service-type
20204 A service type for the @code{certbot} Let's Encrypt client. Its value
20205 must be a @code{certbot-configuration} record as in this example:
20208 (define %nginx-deploy-hook
20210 "nginx-deploy-hook"
20211 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
20212 (kill pid SIGHUP))))
20214 (service certbot-service-type
20215 (certbot-configuration
20216 (email "foo@@example.net")
20219 (certificate-configuration
20220 (domains '("example.net" "www.example.net"))
20221 (deploy-hook %nginx-deploy-hook))
20222 (certificate-configuration
20223 (domains '("bar.example.net")))))))
20226 See below for details about @code{certbot-configuration}.
20229 @deftp {Data Type} certbot-configuration
20230 Data type representing the configuration of the @code{certbot} service.
20231 This type has the following parameters:
20234 @item @code{package} (default: @code{certbot})
20235 The certbot package to use.
20237 @item @code{webroot} (default: @code{/var/www})
20238 The directory from which to serve the Let's Encrypt challenge/response
20241 @item @code{certificates} (default: @code{()})
20242 A list of @code{certificates-configuration}s for which to generate
20243 certificates and request signatures. Each certificate has a @code{name}
20244 and several @code{domains}.
20247 Mandatory email used for registration, recovery contact, and important
20248 account notifications.
20250 @item @code{rsa-key-size} (default: @code{2048})
20251 Size of the RSA key.
20253 @item @code{default-location} (default: @i{see below})
20254 The default @code{nginx-location-configuration}. Because @code{certbot}
20255 needs to be able to serve challenges and responses, it needs to be able
20256 to run a web server. It does so by extending the @code{nginx} web
20257 service with an @code{nginx-server-configuration} listening on the
20258 @var{domains} on port 80, and which has a
20259 @code{nginx-location-configuration} for the @code{/.well-known/} URI
20260 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
20261 these nginx configuration data types.
20263 Requests to other URL paths will be matched by the
20264 @code{default-location}, which if present is added to all
20265 @code{nginx-server-configuration}s.
20267 By default, the @code{default-location} will issue a redirect from
20268 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
20269 you to define what to serve on your site via @code{https}.
20271 Pass @code{#f} to not issue a default location.
20275 @deftp {Data Type} certificate-configuration
20276 Data type representing the configuration of a certificate.
20277 This type has the following parameters:
20280 @item @code{name} (default: @i{see below})
20281 This name is used by Certbot for housekeeping and in file paths; it
20282 doesn't affect the content of the certificate itself. To see
20283 certificate names, run @code{certbot certificates}.
20285 Its default is the first provided domain.
20287 @item @code{domains} (default: @code{()})
20288 The first domain provided will be the subject CN of the certificate, and
20289 all domains will be Subject Alternative Names on the certificate.
20291 @item @code{challenge} (default: @code{#f})
20292 The challenge type that has to be run by certbot. If @code{#f} is specified,
20293 default to the HTTP challenge. If a value is specified, defaults to the
20294 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
20295 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}).
20297 @item @code{authentication-hook} (default: @code{#f})
20298 Command to be run in a shell once for each certificate challenge to be
20299 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
20300 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
20301 contains the validation string and @code{$CERTBOT_TOKEN} contains the
20302 file name of the resource requested when performing an HTTP-01 challenge.
20304 @item @code{cleanup-hook} (default: @code{#f})
20305 Command to be run in a shell once for each certificate challenge that
20306 have been answered by the @code{auth-hook}. For this command, the shell
20307 variables available in the @code{auth-hook} script are still available, and
20308 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
20309 of the @code{auth-hook} script.
20311 @item @code{deploy-hook} (default: @code{#f})
20312 Command to be run in a shell once for each successfully issued
20313 certificate. For this command, the shell variable
20314 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
20315 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
20316 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
20317 contain a space-delimited list of renewed certificate domains (for
20318 example, @samp{"example.com www.example.com"}.
20323 For each @code{certificate-configuration}, the certificate is saved to
20324 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
20325 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
20327 @subsection DNS Services
20328 @cindex DNS (domain name system)
20329 @cindex domain name system (DNS)
20331 The @code{(gnu services dns)} module provides services related to the
20332 @dfn{domain name system} (DNS). It provides a server service for hosting
20333 an @emph{authoritative} DNS server for multiple zones, slave or master.
20334 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
20335 caching and forwarding DNS server for the LAN, which uses
20336 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
20338 @subsubheading Knot Service
20340 An example configuration of an authoritative server for two zones, one master
20344 (define-zone-entries example.org.zone
20345 ;; Name TTL Class Type Data
20346 ("@@" "" "IN" "A" "127.0.0.1")
20347 ("@@" "" "IN" "NS" "ns")
20348 ("ns" "" "IN" "A" "127.0.0.1"))
20350 (define master-zone
20351 (knot-zone-configuration
20352 (domain "example.org")
20354 (origin "example.org")
20355 (entries example.org.zone)))))
20358 (knot-zone-configuration
20359 (domain "plop.org")
20360 (dnssec-policy "default")
20361 (master (list "plop-master"))))
20363 (define plop-master
20364 (knot-remote-configuration
20366 (address (list "208.76.58.171"))))
20370 (services (cons* (service knot-service-type
20371 (knot-configuration
20372 (remotes (list plop-master))
20373 (zones (list master-zone slave-zone))))
20378 @deffn {Scheme Variable} knot-service-type
20379 This is the type for the Knot DNS server.
20381 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
20382 zones, that is to say domain names you would buy from a registrar. This server
20383 is not a resolver, meaning that it can only resolve names for which it is
20384 authoritative. This server can be configured to serve zones as a master server
20385 or a slave server as a per-zone basis. Slave zones will get their data from
20386 masters, and will serve it as an authoritative server. From the point of view
20387 of a resolver, there is no difference between master and slave.
20389 The following data types are used to configure the Knot DNS server:
20392 @deftp {Data Type} knot-key-configuration
20393 Data type representing a key.
20394 This type has the following parameters:
20397 @item @code{id} (default: @code{""})
20398 An identifier for other configuration fields to refer to this key. IDs must
20399 be unique and must not be empty.
20401 @item @code{algorithm} (default: @code{#f})
20402 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
20403 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
20404 and @code{'hmac-sha512}.
20406 @item @code{secret} (default: @code{""})
20407 The secret key itself.
20412 @deftp {Data Type} knot-acl-configuration
20413 Data type representing an Access Control List (ACL) configuration.
20414 This type has the following parameters:
20417 @item @code{id} (default: @code{""})
20418 An identifier for ether configuration fields to refer to this key. IDs must be
20419 unique and must not be empty.
20421 @item @code{address} (default: @code{'()})
20422 An ordered list of IP addresses, network subnets, or network ranges represented
20423 with strings. The query must match one of them. Empty value means that
20424 address match is not required.
20426 @item @code{key} (default: @code{'()})
20427 An ordered list of references to keys represented with strings. The string
20428 must match a key ID defined in a @code{knot-key-configuration}. No key means
20429 that a key is not require to match that ACL.
20431 @item @code{action} (default: @code{'()})
20432 An ordered list of actions that are permitted or forbidden by this ACL. Possible
20433 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
20434 and @code{'update}.
20436 @item @code{deny?} (default: @code{#f})
20437 When true, the ACL defines restrictions. Listed actions are forbidden. When
20438 false, listed actions are allowed.
20443 @deftp {Data Type} zone-entry
20444 Data type represnting a record entry in a zone file.
20445 This type has the following parameters:
20448 @item @code{name} (default: @code{"@@"})
20449 The name of the record. @code{"@@"} refers to the origin of the zone. Names
20450 are relative to the origin of the zone. For example, in the @code{example.org}
20451 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
20452 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
20453 refers to @code{ns.example.org}.
20455 @item @code{ttl} (default: @code{""})
20456 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
20458 @item @code{class} (default: @code{"IN"})
20459 The class of the record. Knot currently supports only @code{"IN"} and
20460 partially @code{"CH"}.
20462 @item @code{type} (default: @code{"A"})
20463 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
20464 address), NS (Name Server) and MX (Mail eXchange). Many other types are
20467 @item @code{data} (default: @code{""})
20468 The data contained in the record. For instance an IP address associated with
20469 an A record, or a domain name associated with an NS record. Remember that
20470 domain names are relative to the origin unless they end with a dot.
20475 @deftp {Data Type} zone-file
20476 Data type representing the content of a zone file.
20477 This type has the following parameters:
20480 @item @code{entries} (default: @code{'()})
20481 The list of entries. The SOA record is taken care of, so you don't need to
20482 put it in the list of entries. This list should probably contain an entry
20483 for your primary authoritative DNS server. Other than using a list of entries
20484 directly, you can use @code{define-zone-entries} to define a object containing
20485 the list of entries more easily, that you can later pass to the @code{entries}
20486 field of the @code{zone-file}.
20488 @item @code{origin} (default: @code{""})
20489 The name of your zone. This parameter cannot be empty.
20491 @item @code{ns} (default: @code{"ns"})
20492 The domain of your primary authoritative DNS server. The name is relative to
20493 the origin, unless it ends with a dot. It is mandatory that this primary
20494 DNS server corresponds to an NS record in the zone and that it is associated
20495 to an IP address in the list of entries.
20497 @item @code{mail} (default: @code{"hostmaster"})
20498 An email address people can contact you at, as the owner of the zone. This
20499 is translated as @code{<mail>@@<origin>}.
20501 @item @code{serial} (default: @code{1})
20502 The serial number of the zone. As this is used to keep track of changes by
20503 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
20504 Always increment it when you make a change in your zone.
20506 @item @code{refresh} (default: @code{(* 2 24 3600)})
20507 The frequency at which slaves will do a zone transfer. This value is a number
20508 of seconds. It can be computed by multiplications or with
20509 @code{(string->duration)}.
20511 @item @code{retry} (default: @code{(* 15 60)})
20512 The period after which a slave will retry to contact its master when it fails
20513 to do so a first time.
20515 @item @code{expiry} (default: @code{(* 14 24 3600)})
20516 Default TTL of records. Existing records are considered correct for at most
20517 this amount of time. After this period, resolvers will invalidate their cache
20518 and check again that it still exists.
20520 @item @code{nx} (default: @code{3600})
20521 Default TTL of inexistant records. This delay is usually short because you want
20522 your new domains to reach everyone quickly.
20527 @deftp {Data Type} knot-remote-configuration
20528 Data type representing a remote configuration.
20529 This type has the following parameters:
20532 @item @code{id} (default: @code{""})
20533 An identifier for other configuration fields to refer to this remote. IDs must
20534 be unique and must not be empty.
20536 @item @code{address} (default: @code{'()})
20537 An ordered list of destination IP addresses. Addresses are tried in sequence.
20538 An optional port can be given with the @@ separator. For instance:
20539 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
20541 @item @code{via} (default: @code{'()})
20542 An ordered list of source IP addresses. An empty list will have Knot choose
20543 an appropriate source IP. An optional port can be given with the @@ separator.
20544 The default is to choose at random.
20546 @item @code{key} (default: @code{#f})
20547 A reference to a key, that is a string containing the identifier of a key
20548 defined in a @code{knot-key-configuration} field.
20553 @deftp {Data Type} knot-keystore-configuration
20554 Data type representing a keystore to hold dnssec keys.
20555 This type has the following parameters:
20558 @item @code{id} (default: @code{""})
20559 The id of the keystore. It must not be empty.
20561 @item @code{backend} (default: @code{'pem})
20562 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
20564 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
20565 The configuration string of the backend. An example for the PKCS#11 is:
20566 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
20567 For the pem backend, the string reprensents a path in the file system.
20572 @deftp {Data Type} knot-policy-configuration
20573 Data type representing a dnssec policy. Knot DNS is able to automatically
20574 sign your zones. It can either generate and manage your keys automatically or
20575 use keys that you generate.
20577 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
20578 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
20579 zone. In order to be trusted, the KSK needs to be present in the parent zone
20580 (usually a top-level domain). If your registrar supports dnssec, you will
20581 have to send them your KSK's hash so they can add a DS record in their zone.
20582 This is not automated and need to be done each time you change your KSK.
20584 The policy also defines the lifetime of keys. Usually, ZSK can be changed
20585 easily and use weaker cryptographic functions (they use lower parameters) in
20586 order to sign records quickly, so they are changed often. The KSK however
20587 requires manual interaction with the registrar, so they are changed less often
20588 and use stronger parameters because they sign only one record.
20590 This type has the following parameters:
20593 @item @code{id} (default: @code{""})
20594 The id of the policy. It must not be empty.
20596 @item @code{keystore} (default: @code{"default"})
20597 A reference to a keystore, that is a string containing the identifier of a
20598 keystore defined in a @code{knot-keystore-configuration} field. The
20599 @code{"default"} identifier means the default keystore (a kasp database that
20600 was setup by this service).
20602 @item @code{manual?} (default: @code{#f})
20603 Whether the key management is manual or automatic.
20605 @item @code{single-type-signing?} (default: @code{#f})
20606 When @code{#t}, use the Single-Type Signing Scheme.
20608 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
20609 An algorithm of signing keys and issued signatures.
20611 @item @code{ksk-size} (default: @code{256})
20612 The length of the KSK. Note that this value is correct for the default
20613 algorithm, but would be unsecure for other algorithms.
20615 @item @code{zsk-size} (default: @code{256})
20616 The length of the ZSK. Note that this value is correct for the default
20617 algorithm, but would be unsecure for other algorithms.
20619 @item @code{dnskey-ttl} (default: @code{'default})
20620 The TTL value for DNSKEY records added into zone apex. The special
20621 @code{'default} value means same as the zone SOA TTL.
20623 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
20624 The period between ZSK publication and the next rollover initiation.
20626 @item @code{propagation-delay} (default: @code{(* 24 3600)})
20627 An extra delay added for each key rollover step. This value should be high
20628 enough to cover propagation of data from the master server to all slaves.
20630 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
20631 A validity period of newly issued signatures.
20633 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
20634 A period how long before a signature expiration the signature will be refreshed.
20636 @item @code{nsec3?} (default: @code{#f})
20637 When @code{#t}, NSEC3 will be used instead of NSEC.
20639 @item @code{nsec3-iterations} (default: @code{5})
20640 The number of additional times the hashing is performed.
20642 @item @code{nsec3-salt-length} (default: @code{8})
20643 The length of a salt field in octets, which is appended to the original owner
20644 name before hashing.
20646 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
20647 The validity period of newly issued salt field.
20652 @deftp {Data Type} knot-zone-configuration
20653 Data type representing a zone served by Knot.
20654 This type has the following parameters:
20657 @item @code{domain} (default: @code{""})
20658 The domain served by this configuration. It must not be empty.
20660 @item @code{file} (default: @code{""})
20661 The file where this zone is saved. This parameter is ignored by master zones.
20662 Empty means default location that depends on the domain name.
20664 @item @code{zone} (default: @code{(zone-file)})
20665 The content of the zone file. This parameter is ignored by slave zones. It
20666 must contain a zone-file record.
20668 @item @code{master} (default: @code{'()})
20669 A list of master remotes. When empty, this zone is a master. When set, this
20670 zone is a slave. This is a list of remotes identifiers.
20672 @item @code{ddns-master} (default: @code{#f})
20673 The main master. When empty, it defaults to the first master in the list of
20676 @item @code{notify} (default: @code{'()})
20677 A list of slave remote identifiers.
20679 @item @code{acl} (default: @code{'()})
20680 A list of acl identifiers.
20682 @item @code{semantic-checks?} (default: @code{#f})
20683 When set, this adds more semantic checks to the zone.
20685 @item @code{disable-any?} (default: @code{#f})
20686 When set, this forbids queries of the ANY type.
20688 @item @code{zonefile-sync} (default: @code{0})
20689 The delay between a modification in memory and on disk. 0 means immediate
20692 @item @code{zonefile-load} (default: @code{#f})
20693 The way the zone file contents are applied during zone load. Possible values
20697 @item @code{#f} for using the default value from Knot,
20698 @item @code{'none} for not using the zone file at all,
20699 @item @code{'difference} for computing the difference between already available
20700 contents and zone contents and applying it to the current zone contents,
20701 @item @code{'difference-no-serial} for the same as @code{'difference}, but
20702 ignoring the SOA serial in the zone file, while the server takes care of it
20704 @item @code{'whole} for loading zone contents from the zone file.
20707 @item @code{journal-content} (default: @code{#f})
20708 The way the journal is used to store zone and its changes. Possible values
20709 are @code{'none} to not use it at all, @code{'changes} to store changes and
20710 @code{'all} to store contents. @code{#f} does not set this option, so the
20711 default value from Knot is used.
20713 @item @code{max-journal-usage} (default: @code{#f})
20714 The maximum size for the journal on disk. @code{#f} does not set this option,
20715 so the default value from Knot is used.
20717 @item @code{max-journal-depth} (default: @code{#f})
20718 The maximum size of the history. @code{#f} does not set this option, so the
20719 default value from Knot is used.
20721 @item @code{max-zone-size} (default: @code{#f})
20722 The maximum size of the zone file. This limit is enforced for incoming
20723 transfer and updates. @code{#f} does not set this option, so the default
20724 value from Knot is used.
20726 @item @code{dnssec-policy} (default: @code{#f})
20727 A reference to a @code{knot-policy-configuration} record, or the special
20728 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
20731 @item @code{serial-policy} (default: @code{'increment})
20732 A policy between @code{'increment} and @code{'unixtime}.
20737 @deftp {Data Type} knot-configuration
20738 Data type representing the Knot configuration.
20739 This type has the following parameters:
20742 @item @code{knot} (default: @code{knot})
20745 @item @code{run-directory} (default: @code{"/var/run/knot"})
20746 The run directory. This directory will be used for pid file and sockets.
20748 @item @code{includes} (default: @code{'()})
20749 A list of strings or file-like objects denoting other files that must be
20750 included at the top of the configuration file.
20752 @cindex secrets, Knot service
20753 This can be used to manage secrets out-of-band. For example, secret
20754 keys may be stored in an out-of-band file not managed by Guix, and
20755 thus not visible in @file{/gnu/store}---e.g., you could store secret
20756 key configuration in @file{/etc/knot/secrets.conf} and add this file
20757 to the @code{includes} list.
20759 One can generate a secret tsig key (for nsupdate and zone transfers with the
20760 keymgr command from the knot package. Note that the package is not automatically
20761 installed by the service. The following example shows how to generate a new
20765 keymgr -t mysecret > /etc/knot/secrets.conf
20766 chmod 600 /etc/knot/secrets.conf
20769 Also note that the generated key will be named @var{mysecret}, so it is the
20770 name that needs to be used in the @var{key} field of the
20771 @code{knot-acl-configuration} record and in other places that need to refer
20774 It can also be used to add configuration not supported by this interface.
20776 @item @code{listen-v4} (default: @code{"0.0.0.0"})
20777 An ip address on which to listen.
20779 @item @code{listen-v6} (default: @code{"::"})
20780 An ip address on which to listen.
20782 @item @code{listen-port} (default: @code{53})
20783 A port on which to listen.
20785 @item @code{keys} (default: @code{'()})
20786 The list of knot-key-configuration used by this configuration.
20788 @item @code{acls} (default: @code{'()})
20789 The list of knot-acl-configuration used by this configuration.
20791 @item @code{remotes} (default: @code{'()})
20792 The list of knot-remote-configuration used by this configuration.
20794 @item @code{zones} (default: @code{'()})
20795 The list of knot-zone-configuration used by this configuration.
20800 @subsubheading Dnsmasq Service
20802 @deffn {Scheme Variable} dnsmasq-service-type
20803 This is the type of the dnsmasq service, whose value should be an
20804 @code{dnsmasq-configuration} object as in this example:
20807 (service dnsmasq-service-type
20808 (dnsmasq-configuration
20810 (servers '("192.168.1.1"))))
20814 @deftp {Data Type} dnsmasq-configuration
20815 Data type representing the configuration of dnsmasq.
20818 @item @code{package} (default: @var{dnsmasq})
20819 Package object of the dnsmasq server.
20821 @item @code{no-hosts?} (default: @code{#f})
20822 When true, don't read the hostnames in /etc/hosts.
20824 @item @code{port} (default: @code{53})
20825 The port to listen on. Setting this to zero completely disables DNS
20826 responses, leaving only DHCP and/or TFTP functions.
20828 @item @code{local-service?} (default: @code{#t})
20829 Accept DNS queries only from hosts whose address is on a local subnet,
20830 ie a subnet for which an interface exists on the server.
20832 @item @code{listen-addresses} (default: @code{'()})
20833 Listen on the given IP addresses.
20835 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
20836 The file to read the IP address of the upstream nameservers from.
20838 @item @code{no-resolv?} (default: @code{#f})
20839 When true, don't read @var{resolv-file}.
20841 @item @code{servers} (default: @code{'()})
20842 Specify IP address of upstream servers directly.
20844 @item @code{cache-size} (default: @code{150})
20845 Set the size of dnsmasq's cache. Setting the cache size to zero
20848 @item @code{negative-cache?} (default: @code{#t})
20849 When false, disable negative caching.
20854 @subsubheading ddclient Service
20857 The ddclient service described below runs the ddclient daemon, which takes
20858 care of automatically updating DNS entries for service providers such as
20859 @uref{https://dyn.com/dns/, Dyn}.
20861 The following example show instantiates the service with its default
20865 (service ddclient-service-type)
20868 Note that ddclient needs to access credentials that are stored in a
20869 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
20870 @code{secret-file} below.) You are expected to create this file manually, in
20871 an ``out-of-band'' fashion (you @emph{could} make this file part of the
20872 service configuration, for instance by using @code{plain-file}, but it will be
20873 world-readable @i{via} @file{/gnu/store}.) See the examples in the
20874 @file{share/ddclient} directory of the @code{ddclient} package.
20876 @c %start of fragment
20878 Available @code{ddclient-configuration} fields are:
20880 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
20881 The ddclient package.
20885 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
20886 The period after which ddclient will retry to check IP and domain name.
20888 Defaults to @samp{300}.
20892 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
20893 Use syslog for the output.
20895 Defaults to @samp{#t}.
20899 @deftypevr {@code{ddclient-configuration} parameter} string mail
20902 Defaults to @samp{"root"}.
20906 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
20907 Mail failed update to user.
20909 Defaults to @samp{"root"}.
20913 @deftypevr {@code{ddclient-configuration} parameter} string pid
20914 The ddclient PID file.
20916 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
20920 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
20921 Enable SSL support.
20923 Defaults to @samp{#t}.
20927 @deftypevr {@code{ddclient-configuration} parameter} string user
20928 Specifies the user name or ID that is used when running ddclient
20931 Defaults to @samp{"ddclient"}.
20935 @deftypevr {@code{ddclient-configuration} parameter} string group
20936 Group of the user who will run the ddclient program.
20938 Defaults to @samp{"ddclient"}.
20942 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
20943 Secret file which will be appended to @file{ddclient.conf} file. This
20944 file contains credentials for use by ddclient. You are expected to
20945 create it manually.
20947 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
20951 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
20952 Extra options will be appended to @file{ddclient.conf} file.
20954 Defaults to @samp{()}.
20959 @c %end of fragment
20963 @subsection VPN Services
20964 @cindex VPN (virtual private network)
20965 @cindex virtual private network (VPN)
20967 The @code{(gnu services vpn)} module provides services related to
20968 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
20969 your machine to connect to a VPN, and a @emph{server} service for your machine
20970 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
20972 @deffn {Scheme Procedure} openvpn-client-service @
20973 [#:config (openvpn-client-configuration)]
20975 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
20978 @deffn {Scheme Procedure} openvpn-server-service @
20979 [#:config (openvpn-server-configuration)]
20981 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
20983 Both can be run simultaneously.
20986 @c %automatically generated documentation
20988 Available @code{openvpn-client-configuration} fields are:
20990 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
20991 The OpenVPN package.
20995 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
20996 The OpenVPN pid file.
20998 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21002 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
21003 The protocol (UDP or TCP) used to open a channel between clients and
21006 Defaults to @samp{udp}.
21010 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
21011 The device type used to represent the VPN connection.
21013 Defaults to @samp{tun}.
21017 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
21018 The certificate authority to check connections against.
21020 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21024 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
21025 The certificate of the machine the daemon is running on. It should be
21026 signed by the authority given in @code{ca}.
21028 Defaults to @samp{"/etc/openvpn/client.crt"}.
21032 @deftypevr {@code{openvpn-client-configuration} parameter} string key
21033 The key of the machine the daemon is running on. It must be the key whose
21034 certificate is @code{cert}.
21036 Defaults to @samp{"/etc/openvpn/client.key"}.
21040 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
21041 Whether to use the lzo compression algorithm.
21043 Defaults to @samp{#t}.
21047 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
21048 Don't re-read key files across SIGUSR1 or --ping-restart.
21050 Defaults to @samp{#t}.
21054 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
21055 Don't close and reopen TUN/TAP device or run up/down scripts across
21056 SIGUSR1 or --ping-restart restarts.
21058 Defaults to @samp{#t}.
21062 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
21065 Defaults to @samp{3}.
21069 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
21070 Add an additional layer of HMAC authentication on top of the TLS control
21071 channel to protect against DoS attacks.
21073 Defaults to @samp{#f}.
21077 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
21078 Whether to check the server certificate has server usage extension.
21080 Defaults to @samp{#t}.
21084 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
21085 Bind to a specific local port number.
21087 Defaults to @samp{#f}.
21091 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
21092 Retry resolving server address.
21094 Defaults to @samp{#t}.
21098 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
21099 A list of remote servers to connect to.
21101 Defaults to @samp{()}.
21103 Available @code{openvpn-remote-configuration} fields are:
21105 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
21108 Defaults to @samp{"my-server"}.
21112 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
21113 Port number the server listens to.
21115 Defaults to @samp{1194}.
21120 @c %end of automatic openvpn-client documentation
21122 @c %automatically generated documentation
21124 Available @code{openvpn-server-configuration} fields are:
21126 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
21127 The OpenVPN package.
21131 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
21132 The OpenVPN pid file.
21134 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21138 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
21139 The protocol (UDP or TCP) used to open a channel between clients and
21142 Defaults to @samp{udp}.
21146 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
21147 The device type used to represent the VPN connection.
21149 Defaults to @samp{tun}.
21153 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
21154 The certificate authority to check connections against.
21156 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21160 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
21161 The certificate of the machine the daemon is running on. It should be
21162 signed by the authority given in @code{ca}.
21164 Defaults to @samp{"/etc/openvpn/client.crt"}.
21168 @deftypevr {@code{openvpn-server-configuration} parameter} string key
21169 The key of the machine the daemon is running on. It must be the key whose
21170 certificate is @code{cert}.
21172 Defaults to @samp{"/etc/openvpn/client.key"}.
21176 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
21177 Whether to use the lzo compression algorithm.
21179 Defaults to @samp{#t}.
21183 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
21184 Don't re-read key files across SIGUSR1 or --ping-restart.
21186 Defaults to @samp{#t}.
21190 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
21191 Don't close and reopen TUN/TAP device or run up/down scripts across
21192 SIGUSR1 or --ping-restart restarts.
21194 Defaults to @samp{#t}.
21198 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
21201 Defaults to @samp{3}.
21205 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
21206 Add an additional layer of HMAC authentication on top of the TLS control
21207 channel to protect against DoS attacks.
21209 Defaults to @samp{#f}.
21213 @deftypevr {@code{openvpn-server-configuration} parameter} number port
21214 Specifies the port number on which the server listens.
21216 Defaults to @samp{1194}.
21220 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
21221 An ip and mask specifying the subnet inside the virtual network.
21223 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
21227 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
21228 A CIDR notation specifying the IPv6 subnet inside the virtual network.
21230 Defaults to @samp{#f}.
21234 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
21235 The Diffie-Hellman parameters file.
21237 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
21241 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
21242 The file that records client IPs.
21244 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
21248 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
21249 When true, the server will act as a gateway for its clients.
21251 Defaults to @samp{#f}.
21255 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
21256 When true, clients are allowed to talk to each other inside the VPN.
21258 Defaults to @samp{#f}.
21262 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
21263 Causes ping-like messages to be sent back and forth over the link so
21264 that each side knows when the other side has gone down. @code{keepalive}
21265 requires a pair. The first element is the period of the ping sending,
21266 and the second element is the timeout before considering the other side
21271 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
21272 The maximum number of clients.
21274 Defaults to @samp{100}.
21278 @deftypevr {@code{openvpn-server-configuration} parameter} string status
21279 The status file. This file shows a small report on current connection.
21280 It is truncated and rewritten every minute.
21282 Defaults to @samp{"/var/run/openvpn/status"}.
21286 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
21287 The list of configuration for some clients.
21289 Defaults to @samp{()}.
21291 Available @code{openvpn-ccd-configuration} fields are:
21293 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
21296 Defaults to @samp{"client"}.
21300 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
21303 Defaults to @samp{#f}.
21307 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
21310 Defaults to @samp{#f}.
21317 @c %end of automatic openvpn-server documentation
21320 @node Network File System
21321 @subsection Network File System
21324 The @code{(gnu services nfs)} module provides the following services,
21325 which are most commonly used in relation to mounting or exporting
21326 directory trees as @dfn{network file systems} (NFS).
21328 @subsubheading RPC Bind Service
21331 The RPC Bind service provides a facility to map program numbers into
21332 universal addresses.
21333 Many NFS related services use this facility. Hence it is automatically
21334 started when a dependent service starts.
21336 @defvr {Scheme Variable} rpcbind-service-type
21337 A service type for the RPC portmapper daemon.
21341 @deftp {Data Type} rpcbind-configuration
21342 Data type representing the configuration of the RPC Bind Service.
21343 This type has the following parameters:
21345 @item @code{rpcbind} (default: @code{rpcbind})
21346 The rpcbind package to use.
21348 @item @code{warm-start?} (default: @code{#t})
21349 If this parameter is @code{#t}, then the daemon will read a
21350 state file on startup thus reloading state information saved by a previous
21356 @subsubheading Pipefs Pseudo File System
21360 The pipefs file system is used to transfer NFS related data
21361 between the kernel and user space programs.
21363 @defvr {Scheme Variable} pipefs-service-type
21364 A service type for the pipefs pseudo file system.
21367 @deftp {Data Type} pipefs-configuration
21368 Data type representing the configuration of the pipefs pseudo file system service.
21369 This type has the following parameters:
21371 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21372 The directory to which the file system is to be attached.
21377 @subsubheading GSS Daemon Service
21380 @cindex global security system
21382 The @dfn{global security system} (GSS) daemon provides strong security for RPC
21384 Before exchanging RPC requests an RPC client must establish a security
21385 context. Typically this is done using the Kerberos command @command{kinit}
21386 or automatically at login time using PAM services (@pxref{Kerberos Services}).
21388 @defvr {Scheme Variable} gss-service-type
21389 A service type for the Global Security System (GSS) daemon.
21392 @deftp {Data Type} gss-configuration
21393 Data type representing the configuration of the GSS daemon service.
21394 This type has the following parameters:
21396 @item @code{nfs-utils} (default: @code{nfs-utils})
21397 The package in which the @command{rpc.gssd} command is to be found.
21399 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21400 The directory where the pipefs file system is mounted.
21406 @subsubheading IDMAP Daemon Service
21408 @cindex name mapper
21410 The idmap daemon service provides mapping between user IDs and user names.
21411 Typically it is required in order to access file systems mounted via NFSv4.
21413 @defvr {Scheme Variable} idmap-service-type
21414 A service type for the Identity Mapper (IDMAP) daemon.
21417 @deftp {Data Type} idmap-configuration
21418 Data type representing the configuration of the IDMAP daemon service.
21419 This type has the following parameters:
21421 @item @code{nfs-utils} (default: @code{nfs-utils})
21422 The package in which the @command{rpc.idmapd} command is to be found.
21424 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21425 The directory where the pipefs file system is mounted.
21427 @item @code{domain} (default: @code{#f})
21428 The local NFSv4 domain name.
21429 This must be a string or @code{#f}.
21430 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
21435 @node Continuous Integration
21436 @subsection Continuous Integration
21438 @cindex continuous integration
21439 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
21440 continuous integration tool for Guix. It can be used both for development and
21441 for providing substitutes to others (@pxref{Substitutes}).
21443 The @code{(gnu services cuirass)} module provides the following service.
21445 @defvr {Scheme Procedure} cuirass-service-type
21446 The type of the Cuirass service. Its value must be a
21447 @code{cuirass-configuration} object, as described below.
21450 To add build jobs, you have to set the @code{specifications} field of the
21451 configuration. Here is an example of a service that polls the Guix repository
21452 and builds the packages from a manifest. Some of the packages are defined in
21453 the @code{"custom-packages"} input, which is the equivalent of
21454 @code{GUIX_PACKAGE_PATH}.
21457 (define %cuirass-specs
21459 '((#:name . "my-manifest")
21460 (#:load-path-inputs . ("guix"))
21461 (#:package-path-inputs . ("custom-packages"))
21462 (#:proc-input . "guix")
21463 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
21464 (#:proc . cuirass-jobs)
21465 (#:proc-args . ((subset . "manifests")
21466 (systems . ("x86_64-linux"))
21467 (manifests . (("config" . "guix/manifest.scm")))))
21468 (#:inputs . (((#:name . "guix")
21469 (#:url . "git://git.savannah.gnu.org/guix.git")
21470 (#:load-path . ".")
21471 (#:branch . "master")
21472 (#:no-compile? . #t))
21473 ((#:name . "config")
21474 (#:url . "https://git.example.org/config.git")
21475 (#:load-path . ".")
21476 (#:branch . "master")
21477 (#:no-compile? . #t))
21478 ((#:name . "custom-packages")
21479 (#:url . "https://git.example.org/custom-packages.git")
21480 (#:load-path . ".")
21481 (#:branch . "master")
21482 (#:no-compile? . #t)))))))
21484 (service cuirass-service-type
21485 (cuirass-configuration
21486 (specifications %cuirass-specs)))
21489 While information related to build jobs is located directly in the
21490 specifications, global settings for the @command{cuirass} process are
21491 accessible in other @code{cuirass-configuration} fields.
21493 @deftp {Data Type} cuirass-configuration
21494 Data type representing the configuration of Cuirass.
21497 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
21498 Location of the log file.
21500 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
21501 Location of the log file used by the web interface.
21503 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
21504 Location of the repository cache.
21506 @item @code{user} (default: @code{"cuirass"})
21507 Owner of the @code{cuirass} process.
21509 @item @code{group} (default: @code{"cuirass"})
21510 Owner's group of the @code{cuirass} process.
21512 @item @code{interval} (default: @code{60})
21513 Number of seconds between the poll of the repositories followed by the
21516 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
21517 Location of sqlite database which contains the build results and previously
21518 added specifications.
21520 @item @code{ttl} (default: @code{(* 30 24 3600)})
21521 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
21522 are registered for build results. This means that build results are protected
21523 from garbage collection for at least @var{ttl} seconds.
21525 @item @code{port} (default: @code{8081})
21526 Port number used by the HTTP server.
21528 @item @code{host} (default: @code{"localhost"})
21529 Listen on the network interface for @var{host}. The default is to
21530 accept connections from localhost.
21532 @item @code{specifications} (default: @code{#~'()})
21533 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
21534 where a specification is an association list
21535 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
21536 keys are keywords (@code{#:keyword-example}) as shown in the example
21539 @item @code{use-substitutes?} (default: @code{#f})
21540 This allows using substitutes to avoid building every dependencies of a job
21543 @item @code{one-shot?} (default: @code{#f})
21544 Only evaluate specifications and build derivations once.
21546 @item @code{fallback?} (default: @code{#f})
21547 When substituting a pre-built binary fails, fall back to building
21550 @item @code{cuirass} (default: @code{cuirass})
21551 The Cuirass package to use.
21555 @node Power Management Services
21556 @subsection Power Management Services
21559 @cindex power management with TLP
21560 @subsubheading TLP daemon
21562 The @code{(gnu services pm)} module provides a Guix service definition
21563 for the Linux power management tool TLP.
21565 TLP enables various powersaving modes in userspace and kernel.
21566 Contrary to @code{upower-service}, it is not a passive,
21567 monitoring tool, as it will apply custom settings each time a new power
21568 source is detected. More information can be found at
21569 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
21571 @deffn {Scheme Variable} tlp-service-type
21572 The service type for the TLP tool. Its value should be a valid
21573 TLP configuration (see below). To use the default settings, simply
21576 (service tlp-service-type)
21580 By default TLP does not need much configuration but most TLP parameters
21581 can be tweaked using @code{tlp-configuration}.
21583 Each parameter definition is preceded by its type; for example,
21584 @samp{boolean foo} indicates that the @code{foo} parameter
21585 should be specified as a boolean. Types starting with
21586 @code{maybe-} denote parameters that won't show up in TLP config file
21587 when their value is @code{'disabled}.
21589 @c The following documentation was initially generated by
21590 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
21591 @c documentation is better, so we shouldn't hesitate to edit below as
21592 @c needed. However if the change you want to make to this documentation
21593 @c can be done in an automated way, it's probably easier to change
21594 @c (generate-documentation) than to make it below and have to deal with
21595 @c the churn as TLP updates.
21597 Available @code{tlp-configuration} fields are:
21599 @deftypevr {@code{tlp-configuration} parameter} package tlp
21604 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
21605 Set to true if you wish to enable TLP.
21607 Defaults to @samp{#t}.
21611 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
21612 Default mode when no power supply can be detected. Alternatives are AC
21615 Defaults to @samp{"AC"}.
21619 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
21620 Number of seconds Linux kernel has to wait after the disk goes idle,
21621 before syncing on AC.
21623 Defaults to @samp{0}.
21627 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
21628 Same as @code{disk-idle-ac} but on BAT mode.
21630 Defaults to @samp{2}.
21634 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
21635 Dirty pages flushing periodicity, expressed in seconds.
21637 Defaults to @samp{15}.
21641 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
21642 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
21644 Defaults to @samp{60}.
21648 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
21649 CPU frequency scaling governor on AC mode. With intel_pstate driver,
21650 alternatives are powersave and performance. With acpi-cpufreq driver,
21651 alternatives are ondemand, powersave, performance and conservative.
21653 Defaults to @samp{disabled}.
21657 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
21658 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
21660 Defaults to @samp{disabled}.
21664 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
21665 Set the min available frequency for the scaling governor on AC.
21667 Defaults to @samp{disabled}.
21671 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
21672 Set the max available frequency for the scaling governor on AC.
21674 Defaults to @samp{disabled}.
21678 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
21679 Set the min available frequency for the scaling governor on BAT.
21681 Defaults to @samp{disabled}.
21685 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
21686 Set the max available frequency for the scaling governor on BAT.
21688 Defaults to @samp{disabled}.
21692 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
21693 Limit the min P-state to control the power dissipation of the CPU, in AC
21694 mode. Values are stated as a percentage of the available performance.
21696 Defaults to @samp{disabled}.
21700 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
21701 Limit the max P-state to control the power dissipation of the CPU, in AC
21702 mode. Values are stated as a percentage of the available performance.
21704 Defaults to @samp{disabled}.
21708 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
21709 Same as @code{cpu-min-perf-on-ac} on BAT mode.
21711 Defaults to @samp{disabled}.
21715 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
21716 Same as @code{cpu-max-perf-on-ac} on BAT mode.
21718 Defaults to @samp{disabled}.
21722 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
21723 Enable CPU turbo boost feature on AC mode.
21725 Defaults to @samp{disabled}.
21729 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
21730 Same as @code{cpu-boost-on-ac?} on BAT mode.
21732 Defaults to @samp{disabled}.
21736 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
21737 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
21738 used under light load conditions.
21740 Defaults to @samp{#f}.
21744 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
21745 Same as @code{sched-powersave-on-ac?} but on BAT mode.
21747 Defaults to @samp{#t}.
21751 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
21752 Enable Linux kernel NMI watchdog.
21754 Defaults to @samp{#f}.
21758 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
21759 For Linux kernels with PHC patch applied, change CPU voltages. An
21760 example value would be @samp{"F:V F:V F:V F:V"}.
21762 Defaults to @samp{disabled}.
21766 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
21767 Set CPU performance versus energy saving policy on AC. Alternatives are
21768 performance, normal, powersave.
21770 Defaults to @samp{"performance"}.
21774 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
21775 Same as @code{energy-perf-policy-ac} but on BAT mode.
21777 Defaults to @samp{"powersave"}.
21781 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
21786 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
21787 Hard disk advanced power management level.
21791 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
21792 Same as @code{disk-apm-bat} but on BAT mode.
21796 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
21797 Hard disk spin down timeout. One value has to be specified for each
21798 declared hard disk.
21800 Defaults to @samp{disabled}.
21804 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
21805 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
21807 Defaults to @samp{disabled}.
21811 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
21812 Select IO scheduler for disk devices. One value has to be specified for
21813 each declared hard disk. Example alternatives are cfq, deadline and
21816 Defaults to @samp{disabled}.
21820 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
21821 SATA aggressive link power management (ALPM) level. Alternatives are
21822 min_power, medium_power, max_performance.
21824 Defaults to @samp{"max_performance"}.
21828 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
21829 Same as @code{sata-linkpwr-ac} but on BAT mode.
21831 Defaults to @samp{"min_power"}.
21835 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
21836 Exclude specified SATA host devices for link power management.
21838 Defaults to @samp{disabled}.
21842 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
21843 Enable Runtime Power Management for AHCI controller and disks on AC
21846 Defaults to @samp{disabled}.
21850 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
21851 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
21853 Defaults to @samp{disabled}.
21857 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
21858 Seconds of inactivity before disk is suspended.
21860 Defaults to @samp{15}.
21864 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
21865 PCI Express Active State Power Management level. Alternatives are
21866 default, performance, powersave.
21868 Defaults to @samp{"performance"}.
21872 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
21873 Same as @code{pcie-aspm-ac} but on BAT mode.
21875 Defaults to @samp{"powersave"}.
21879 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
21880 Radeon graphics clock speed level. Alternatives are low, mid, high,
21883 Defaults to @samp{"high"}.
21887 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
21888 Same as @code{radeon-power-ac} but on BAT mode.
21890 Defaults to @samp{"low"}.
21894 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
21895 Radeon dynamic power management method (DPM). Alternatives are battery,
21898 Defaults to @samp{"performance"}.
21902 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
21903 Same as @code{radeon-dpm-state-ac} but on BAT mode.
21905 Defaults to @samp{"battery"}.
21909 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
21910 Radeon DPM performance level. Alternatives are auto, low, high.
21912 Defaults to @samp{"auto"}.
21916 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
21917 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
21919 Defaults to @samp{"auto"}.
21923 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
21924 Wifi power saving mode.
21926 Defaults to @samp{#f}.
21930 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
21931 Same as @code{wifi-power-ac?} but on BAT mode.
21933 Defaults to @samp{#t}.
21937 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
21938 Disable wake on LAN.
21940 Defaults to @samp{#t}.
21944 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
21945 Timeout duration in seconds before activating audio power saving on
21946 Intel HDA and AC97 devices. A value of 0 disables power saving.
21948 Defaults to @samp{0}.
21952 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
21953 Same as @code{sound-powersave-ac} but on BAT mode.
21955 Defaults to @samp{1}.
21959 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
21960 Disable controller in powersaving mode on Intel HDA devices.
21962 Defaults to @samp{#t}.
21966 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
21967 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
21968 powered on again by releasing (and reinserting) the eject lever or by
21969 pressing the disc eject button on newer models.
21971 Defaults to @samp{#f}.
21975 @deftypevr {@code{tlp-configuration} parameter} string bay-device
21976 Name of the optical drive device to power off.
21978 Defaults to @samp{"sr0"}.
21982 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
21983 Runtime Power Management for PCI(e) bus devices. Alternatives are on
21986 Defaults to @samp{"on"}.
21990 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
21991 Same as @code{runtime-pm-ac} but on BAT mode.
21993 Defaults to @samp{"auto"}.
21997 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
21998 Runtime Power Management for all PCI(e) bus devices, except blacklisted
22001 Defaults to @samp{#t}.
22005 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
22006 Exclude specified PCI(e) device addresses from Runtime Power Management.
22008 Defaults to @samp{disabled}.
22012 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
22013 Exclude PCI(e) devices assigned to the specified drivers from Runtime
22018 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
22019 Enable USB autosuspend feature.
22021 Defaults to @samp{#t}.
22025 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
22026 Exclude specified devices from USB autosuspend.
22028 Defaults to @samp{disabled}.
22032 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
22033 Exclude WWAN devices from USB autosuspend.
22035 Defaults to @samp{#t}.
22039 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
22040 Include specified devices into USB autosuspend, even if they are already
22041 excluded by the driver or via @code{usb-blacklist-wwan?}.
22043 Defaults to @samp{disabled}.
22047 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
22048 Enable USB autosuspend before shutdown.
22050 Defaults to @samp{disabled}.
22054 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
22055 Restore radio device state (bluetooth, wifi, wwan) from previous
22056 shutdown on system startup.
22058 Defaults to @samp{#f}.
22063 @cindex CPU frequency scaling with thermald
22064 @subsubheading Thermald daemon
22066 The @code{(gnu services pm)} module provides an interface to
22067 thermald, a CPU frequency scaling service which helps prevent overheating.
22069 @defvr {Scheme Variable} thermald-service-type
22070 This is the service type for
22071 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
22072 Thermal Daemon, which is responsible for controlling the thermal state
22073 of processors and preventing overheating.
22076 @deftp {Data Type} thermald-configuration
22077 Data type representing the configuration of @code{thermald-service-type}.
22080 @item @code{ignore-cpuid-check?} (default: @code{#f})
22081 Ignore cpuid check for supported CPU models.
22083 @item @code{thermald} (default: @var{thermald})
22084 Package object of thermald.
22089 @node Audio Services
22090 @subsection Audio Services
22092 The @code{(gnu services audio)} module provides a service to start MPD
22093 (the Music Player Daemon).
22096 @subsubheading Music Player Daemon
22098 The Music Player Daemon (MPD) is a service that can play music while
22099 being controlled from the local machine or over the network by a variety
22102 The following example shows how one might run @code{mpd} as user
22103 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
22106 (service mpd-service-type
22112 @defvr {Scheme Variable} mpd-service-type
22113 The service type for @command{mpd}
22116 @deftp {Data Type} mpd-configuration
22117 Data type representing the configuration of @command{mpd}.
22120 @item @code{user} (default: @code{"mpd"})
22121 The user to run mpd as.
22123 @item @code{music-dir} (default: @code{"~/Music"})
22124 The directory to scan for music files.
22126 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
22127 The directory to store playlists.
22129 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
22130 The location of the music database.
22132 @item @code{state-file} (default: @code{"~/.mpd/state"})
22133 The location of the file that stores current MPD's state.
22135 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
22136 The location of the sticker database.
22138 @item @code{port} (default: @code{"6600"})
22139 The port to run mpd on.
22141 @item @code{address} (default: @code{"any"})
22142 The address that mpd will bind to. To use a Unix domain socket,
22143 an absolute path can be specified here.
22148 @node Virtualization Services
22149 @subsection Virtualization services
22151 The @code{(gnu services virtualization)} module provides services for
22152 the libvirt and virtlog daemons, as well as other virtualization-related
22155 @subsubheading Libvirt daemon
22156 @code{libvirtd} is the server side daemon component of the libvirt
22157 virtualization management system. This daemon runs on host servers
22158 and performs required management tasks for virtualized guests.
22160 @deffn {Scheme Variable} libvirt-service-type
22161 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
22162 Its value must be a @code{libvirt-configuration}.
22165 (service libvirt-service-type
22166 (libvirt-configuration
22167 (unix-sock-group "libvirt")
22168 (tls-port "16555")))
22172 @c Auto-generated with (generate-libvirt-documentation)
22173 Available @code{libvirt-configuration} fields are:
22175 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
22180 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
22181 Flag listening for secure TLS connections on the public TCP/IP port.
22182 must set @code{listen} for this to have any effect.
22184 It is necessary to setup a CA and issue server certificates before using
22187 Defaults to @samp{#t}.
22191 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
22192 Listen for unencrypted TCP connections on the public TCP/IP port. must
22193 set @code{listen} for this to have any effect.
22195 Using the TCP socket requires SASL authentication by default. Only SASL
22196 mechanisms which support data encryption are allowed. This is
22197 DIGEST_MD5 and GSSAPI (Kerberos5)
22199 Defaults to @samp{#f}.
22203 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
22204 Port for accepting secure TLS connections This can be a port number, or
22207 Defaults to @samp{"16514"}.
22211 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
22212 Port for accepting insecure TCP connections This can be a port number,
22215 Defaults to @samp{"16509"}.
22219 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
22220 IP address or hostname used for client connections.
22222 Defaults to @samp{"0.0.0.0"}.
22226 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
22227 Flag toggling mDNS advertisement of the libvirt service.
22229 Alternatively can disable for all services on a host by stopping the
22232 Defaults to @samp{#f}.
22236 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
22237 Default mDNS advertisement name. This must be unique on the immediate
22240 Defaults to @samp{"Virtualization Host <hostname>"}.
22244 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
22245 UNIX domain socket group ownership. This can be used to allow a
22246 'trusted' set of users access to management capabilities without
22249 Defaults to @samp{"root"}.
22253 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
22254 UNIX socket permissions for the R/O socket. This is used for monitoring
22257 Defaults to @samp{"0777"}.
22261 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
22262 UNIX socket permissions for the R/W socket. Default allows only root.
22263 If PolicyKit is enabled on the socket, the default will change to allow
22264 everyone (eg, 0777)
22266 Defaults to @samp{"0770"}.
22270 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
22271 UNIX socket permissions for the admin socket. Default allows only owner
22272 (root), do not change it unless you are sure to whom you are exposing
22275 Defaults to @samp{"0777"}.
22279 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
22280 The directory in which sockets will be found/created.
22282 Defaults to @samp{"/var/run/libvirt"}.
22286 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
22287 Authentication scheme for UNIX read-only sockets. By default socket
22288 permissions allow anyone to connect
22290 Defaults to @samp{"polkit"}.
22294 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
22295 Authentication scheme for UNIX read-write sockets. By default socket
22296 permissions only allow root. If PolicyKit support was compiled into
22297 libvirt, the default will be to use 'polkit' auth.
22299 Defaults to @samp{"polkit"}.
22303 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
22304 Authentication scheme for TCP sockets. If you don't enable SASL, then
22305 all TCP traffic is cleartext. Don't do this outside of a dev/test
22308 Defaults to @samp{"sasl"}.
22312 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
22313 Authentication scheme for TLS sockets. TLS sockets already have
22314 encryption provided by the TLS layer, and limited authentication is done
22317 It is possible to make use of any SASL authentication mechanism as well,
22318 by using 'sasl' for this option
22320 Defaults to @samp{"none"}.
22324 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
22325 API access control scheme.
22327 By default an authenticated user is allowed access to all APIs. Access
22328 drivers can place restrictions on this.
22330 Defaults to @samp{()}.
22334 @deftypevr {@code{libvirt-configuration} parameter} string key-file
22335 Server key file path. If set to an empty string, then no private key is
22338 Defaults to @samp{""}.
22342 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
22343 Server key file path. If set to an empty string, then no certificate is
22346 Defaults to @samp{""}.
22350 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
22351 Server key file path. If set to an empty string, then no CA certificate
22354 Defaults to @samp{""}.
22358 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
22359 Certificate revocation list path. If set to an empty string, then no
22362 Defaults to @samp{""}.
22366 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
22367 Disable verification of our own server certificates.
22369 When libvirtd starts it performs some sanity checks against its own
22372 Defaults to @samp{#f}.
22376 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
22377 Disable verification of client certificates.
22379 Client certificate verification is the primary authentication mechanism.
22380 Any client which does not present a certificate signed by the CA will be
22383 Defaults to @samp{#f}.
22387 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
22388 Whitelist of allowed x509 Distinguished Name.
22390 Defaults to @samp{()}.
22394 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
22395 Whitelist of allowed SASL usernames. The format for username depends on
22396 the SASL authentication mechanism.
22398 Defaults to @samp{()}.
22402 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
22403 Override the compile time default TLS priority string. The default is
22404 usually "NORMAL" unless overridden at build time. Only set this is it
22405 is desired for libvirt to deviate from the global default settings.
22407 Defaults to @samp{"NORMAL"}.
22411 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
22412 Maximum number of concurrent client connections to allow over all
22415 Defaults to @samp{5000}.
22419 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
22420 Maximum length of queue of connections waiting to be accepted by the
22421 daemon. Note, that some protocols supporting retransmission may obey
22422 this so that a later reattempt at connection succeeds.
22424 Defaults to @samp{1000}.
22428 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
22429 Maximum length of queue of accepted but not yet authenticated clients.
22430 Set this to zero to turn this feature off
22432 Defaults to @samp{20}.
22436 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
22437 Number of workers to start up initially.
22439 Defaults to @samp{5}.
22443 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
22444 Maximum number of worker threads.
22446 If the number of active clients exceeds @code{min-workers}, then more
22447 threads are spawned, up to max_workers limit. Typically you'd want
22448 max_workers to equal maximum number of clients allowed.
22450 Defaults to @samp{20}.
22454 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
22455 Number of priority workers. If all workers from above pool are stuck,
22456 some calls marked as high priority (notably domainDestroy) can be
22457 executed in this pool.
22459 Defaults to @samp{5}.
22463 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
22464 Total global limit on concurrent RPC calls.
22466 Defaults to @samp{20}.
22470 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
22471 Limit on concurrent requests from a single client connection. To avoid
22472 one client monopolizing the server this should be a small fraction of
22473 the global max_requests and max_workers parameter.
22475 Defaults to @samp{5}.
22479 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
22480 Same as @code{min-workers} but for the admin interface.
22482 Defaults to @samp{1}.
22486 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
22487 Same as @code{max-workers} but for the admin interface.
22489 Defaults to @samp{5}.
22493 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
22494 Same as @code{max-clients} but for the admin interface.
22496 Defaults to @samp{5}.
22500 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
22501 Same as @code{max-queued-clients} but for the admin interface.
22503 Defaults to @samp{5}.
22507 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
22508 Same as @code{max-client-requests} but for the admin interface.
22510 Defaults to @samp{5}.
22514 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
22515 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22517 Defaults to @samp{3}.
22521 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
22524 A filter allows to select a different logging level for a given category
22525 of logs The format for a filter is one of:
22536 where @code{name} is a string which is matched against the category
22537 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22538 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22539 be a substring of the full category name, in order to match multiple
22540 similar categories), the optional "+" prefix tells libvirt to log stack
22541 trace for each message matching name, and @code{x} is the minimal level
22542 where matching messages should be logged:
22559 Multiple filters can be defined in a single filters statement, they just
22560 need to be separated by spaces.
22562 Defaults to @samp{"3:remote 4:event"}.
22566 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
22569 An output is one of the places to save logging information. The format
22570 for an output can be:
22574 output goes to stderr
22576 @item x:syslog:name
22577 use syslog for the output and use the given name as the ident
22579 @item x:file:file_path
22580 output to a file, with the given filepath
22583 output to journald logging system
22587 In all case the x prefix is the minimal level, acting as a filter
22604 Multiple outputs can be defined, they just need to be separated by
22607 Defaults to @samp{"3:stderr"}.
22611 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
22612 Allows usage of the auditing subsystem to be altered
22616 0: disable all auditing
22619 1: enable auditing, only if enabled on host
22622 2: enable auditing, and exit if disabled on host.
22626 Defaults to @samp{1}.
22630 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
22631 Send audit messages via libvirt logging infrastructure.
22633 Defaults to @samp{#f}.
22637 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
22638 Host UUID. UUID must not have all digits be the same.
22640 Defaults to @samp{""}.
22644 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
22645 Source to read host UUID.
22649 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
22652 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
22656 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
22659 Defaults to @samp{"smbios"}.
22663 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
22664 A keepalive message is sent to a client after @code{keepalive_interval}
22665 seconds of inactivity to check if the client is still responding. If
22666 set to -1, libvirtd will never send keepalive requests; however clients
22667 can still send them and the daemon will send responses.
22669 Defaults to @samp{5}.
22673 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
22674 Maximum number of keepalive messages that are allowed to be sent to the
22675 client without getting any response before the connection is considered
22678 In other words, the connection is automatically closed approximately
22679 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
22680 the last message received from the client. When @code{keepalive-count}
22681 is set to 0, connections will be automatically closed after
22682 @code{keepalive-interval} seconds of inactivity without sending any
22683 keepalive messages.
22685 Defaults to @samp{5}.
22689 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
22690 Same as above but for admin interface.
22692 Defaults to @samp{5}.
22696 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
22697 Same as above but for admin interface.
22699 Defaults to @samp{5}.
22703 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
22704 Timeout for Open vSwitch calls.
22706 The @code{ovs-vsctl} utility is used for the configuration and its
22707 timeout option is set by default to 5 seconds to avoid potential
22708 infinite waits blocking libvirt.
22710 Defaults to @samp{5}.
22714 @c %end of autogenerated docs
22716 @subsubheading Virtlog daemon
22717 The virtlogd service is a server side daemon component of libvirt that is
22718 used to manage logs from virtual machine consoles.
22720 This daemon is not used directly by libvirt client applications, rather it
22721 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
22722 standalone daemon, the main @code{libvirtd} daemon can be restarted without
22723 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
22724 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
22726 @deffn {Scheme Variable} virtlog-service-type
22727 This is the type of the virtlog daemon.
22728 Its value must be a @code{virtlog-configuration}.
22731 (service virtlog-service-type
22732 (virtlog-configuration
22733 (max-clients 1000)))
22737 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
22738 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22740 Defaults to @samp{3}.
22744 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
22747 A filter allows to select a different logging level for a given category
22748 of logs The format for a filter is one of:
22759 where @code{name} is a string which is matched against the category
22760 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22761 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22762 be a substring of the full category name, in order to match multiple
22763 similar categories), the optional "+" prefix tells libvirt to log stack
22764 trace for each message matching name, and @code{x} is the minimal level
22765 where matching messages should be logged:
22782 Multiple filters can be defined in a single filters statement, they just
22783 need to be separated by spaces.
22785 Defaults to @samp{"3:remote 4:event"}.
22789 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
22792 An output is one of the places to save logging information The format
22793 for an output can be:
22797 output goes to stderr
22799 @item x:syslog:name
22800 use syslog for the output and use the given name as the ident
22802 @item x:file:file_path
22803 output to a file, with the given filepath
22806 output to journald logging system
22810 In all case the x prefix is the minimal level, acting as a filter
22827 Multiple outputs can be defined, they just need to be separated by
22830 Defaults to @samp{"3:stderr"}.
22834 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
22835 Maximum number of concurrent client connections to allow over all
22838 Defaults to @samp{1024}.
22842 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
22843 Maximum file size before rolling over.
22845 Defaults to @samp{2MB}
22849 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
22850 Maximum number of backup files to keep.
22852 Defaults to @samp{3}
22856 @subsubheading Transparent Emulation with QEMU
22859 @cindex @code{binfmt_misc}
22860 @code{qemu-binfmt-service-type} provides support for transparent
22861 emulation of program binaries built for different architectures---e.g.,
22862 it allows you to transparently execute an ARMv7 program on an x86_64
22863 machine. It achieves this by combining the @uref{https://www.qemu.org,
22864 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
22866 @defvr {Scheme Variable} qemu-binfmt-service-type
22867 This is the type of the QEMU/binfmt service for transparent emulation.
22868 Its value must be a @code{qemu-binfmt-configuration} object, which
22869 specifies the QEMU package to use as well as the architecture we want to
22873 (service qemu-binfmt-service-type
22874 (qemu-binfmt-configuration
22875 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
22878 In this example, we enable transparent emulation for the ARM and aarch64
22879 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
22880 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
22881 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
22884 @deftp {Data Type} qemu-binfmt-configuration
22885 This is the configuration for the @code{qemu-binfmt} service.
22888 @item @code{platforms} (default: @code{'()})
22889 The list of emulated QEMU platforms. Each item must be a @dfn{platform
22890 object} as returned by @code{lookup-qemu-platforms} (see below).
22892 @item @code{guix-support?} (default: @code{#f})
22893 When it is true, QEMU and all its dependencies are added to the build
22894 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
22895 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
22896 handlers to be used within the build environment, which in turn means
22897 that you can transparently build programs for another architecture.
22899 For example, let's suppose you're on an x86_64 machine and you have this
22903 (service qemu-binfmt-service-type
22904 (qemu-binfmt-configuration
22905 (platforms (lookup-qemu-platforms "arm"))
22906 (guix-support? #t)))
22912 guix build -s armhf-linux inkscape
22916 and it will build Inkscape for ARMv7 @emph{as if it were a native
22917 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
22918 if you'd like to test a package build for an architecture you don't have
22921 @item @code{qemu} (default: @code{qemu})
22922 The QEMU package to use.
22926 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
22927 Return the list of QEMU platform objects corresponding to
22928 @var{platforms}@dots{}. @var{platforms} must be a list of strings
22929 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
22930 @code{"mips64el"}, and so on.
22933 @deffn {Scheme Procedure} qemu-platform? @var{obj}
22934 Return true if @var{obj} is a platform object.
22937 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
22938 Return the name of @var{platform}---a string such as @code{"arm"}.
22941 @node Version Control Services
22942 @subsection Version Control Services
22944 The @code{(gnu services version-control)} module provides a service to
22945 allow remote access to local Git repositories. There are three options:
22946 the @code{git-daemon-service}, which provides access to repositories via
22947 the @code{git://} unsecured TCP-based protocol, extending the
22948 @code{nginx} web server to proxy some requests to
22949 @code{git-http-backend}, or providing a web interface with
22950 @code{cgit-service-type}.
22952 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
22954 Return a service that runs @command{git daemon}, a simple TCP server to
22955 expose repositories over the Git protocol for anonymous access.
22957 The optional @var{config} argument should be a
22958 @code{<git-daemon-configuration>} object, by default it allows read-only
22959 access to exported@footnote{By creating the magic file
22960 "git-daemon-export-ok" in the repository directory.} repositories under
22965 @deftp {Data Type} git-daemon-configuration
22966 Data type representing the configuration for @code{git-daemon-service}.
22969 @item @code{package} (default: @var{git})
22970 Package object of the Git distributed version control system.
22972 @item @code{export-all?} (default: @var{#f})
22973 Whether to allow access for all Git repositories, even if they do not
22974 have the @file{git-daemon-export-ok} file.
22976 @item @code{base-path} (default: @file{/srv/git})
22977 Whether to remap all the path requests as relative to the given path.
22978 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
22979 then if you later try to pull @code{git://example.com/hello.git}, git
22980 daemon will interpret the path as @code{/srv/git/hello.git}.
22982 @item @code{user-path} (default: @var{#f})
22983 Whether to allow @code{~user} notation to be used in requests. When
22984 specified with empty string, requests to @code{git://host/~alice/foo} is
22985 taken as a request to access @code{foo} repository in the home directory
22986 of user @code{alice}. If @var{(user-path "path")} is specified, the
22987 same request is taken as a request to access @code{path/foo} repository
22988 in the home directory of user @code{alice}.
22990 @item @code{listen} (default: @var{'()})
22991 Whether to listen on specific IP addresses or hostnames, defaults to
22994 @item @code{port} (default: @var{#f})
22995 Whether to listen on an alternative port, which defaults to 9418.
22997 @item @code{whitelist} (default: @var{'()})
22998 If not empty, only allow access to this list of directories.
23000 @item @code{extra-options} (default: @var{'()})
23001 Extra options will be passed to @code{git daemon}, please run
23002 @command{man git-daemon} for more information.
23007 The @code{git://} protocol lacks authentication. When you pull from a
23008 repository fetched via @code{git://}, you don't know whether the data you
23009 receive was modified or is even coming from the specified host, and your
23010 connection is subject to eavesdropping. It's better to use an authenticated
23011 and encrypted transport, such as @code{https}. Although Git allows you
23012 to serve repositories using unsophisticated file-based web servers,
23013 there is a faster protocol implemented by the @code{git-http-backend}
23014 program. This program is the back-end of a proper Git web service. It
23015 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
23016 on running the necessary @code{fcgiwrap} daemon.
23018 Guix has a separate configuration data type for serving Git repositories
23021 @deftp {Data Type} git-http-configuration
23022 Data type representing the configuration for @code{git-http-service}.
23025 @item @code{package} (default: @var{git})
23026 Package object of the Git distributed version control system.
23028 @item @code{git-root} (default: @file{/srv/git})
23029 Directory containing the Git repositories to expose to the world.
23031 @item @code{export-all?} (default: @var{#f})
23032 Whether to expose access for all Git repositories in @var{git-root},
23033 even if they do not have the @file{git-daemon-export-ok} file.
23035 @item @code{uri-path} (default: @file{/git/})
23036 Path prefix for Git access. With the default @code{/git/} prefix, this
23037 will map @code{http://@var{server}/git/@var{repo}.git} to
23038 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
23039 with this prefix are not passed on to this Git instance.
23041 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
23042 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
23047 There is no @code{git-http-service-type}, currently; instead you can
23048 create an @code{nginx-location-configuration} from a
23049 @code{git-http-configuration} and then add that location to a web
23052 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
23053 [config=(git-http-configuration)]
23054 Compute an @code{nginx-location-configuration} that corresponds to the
23055 given Git http configuration. An example nginx service definition to
23056 serve the default @file{/srv/git} over HTTPS might be:
23059 (service nginx-service-type
23060 (nginx-configuration
23063 (nginx-server-configuration
23064 (listen '("443 ssl"))
23065 (server-name "git.my-host.org")
23067 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
23068 (ssl-certificate-key
23069 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
23072 (git-http-nginx-location-configuration
23073 (git-http-configuration (uri-path "/"))))))))))
23076 This example assumes that you are using Let's Encrypt to get your TLS
23077 certificate. @xref{Certificate Services}. The default @code{certbot}
23078 service will redirect all HTTP traffic on @code{git.my-host.org} to
23079 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
23080 system services. @xref{Web Services}.
23083 @subsubheading Cgit Service
23085 @cindex Cgit service
23086 @cindex Git, web interface
23087 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
23088 repositories written in C.
23090 The following example will configure the service with default values.
23091 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
23094 (service cgit-service-type)
23097 The @code{file-object} type designates either a file-like object
23098 (@pxref{G-Expressions, file-like objects}) or a string.
23100 @c %start of fragment
23102 Available @code{cgit-configuration} fields are:
23104 @deftypevr {@code{cgit-configuration} parameter} package package
23109 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
23110 NGINX configuration.
23114 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
23115 Specifies a command which will be invoked to format the content of about
23116 pages (both top-level and for each repository).
23118 Defaults to @samp{""}.
23122 @deftypevr {@code{cgit-configuration} parameter} string agefile
23123 Specifies a path, relative to each repository path, which can be used to
23124 specify the date and time of the youngest commit in the repository.
23126 Defaults to @samp{""}.
23130 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
23131 Specifies a command that will be invoked for authenticating repository
23134 Defaults to @samp{""}.
23138 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
23139 Flag which, when set to @samp{age}, enables date ordering in the branch
23140 ref list, and when set @samp{name} enables ordering by branch name.
23142 Defaults to @samp{"name"}.
23146 @deftypevr {@code{cgit-configuration} parameter} string cache-root
23147 Path used to store the cgit cache entries.
23149 Defaults to @samp{"/var/cache/cgit"}.
23153 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
23154 Number which specifies the time-to-live, in minutes, for the cached
23155 version of repository pages accessed with a fixed SHA1.
23157 Defaults to @samp{-1}.
23161 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
23162 Number which specifies the time-to-live, in minutes, for the cached
23163 version of repository pages accessed without a fixed SHA1.
23165 Defaults to @samp{5}.
23169 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
23170 Number which specifies the time-to-live, in minutes, for the cached
23171 version of the repository summary page.
23173 Defaults to @samp{5}.
23177 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
23178 Number which specifies the time-to-live, in minutes, for the cached
23179 version of the repository index page.
23181 Defaults to @samp{5}.
23185 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
23186 Number which specifies the time-to-live, in minutes, for the result of
23187 scanning a path for Git repositories.
23189 Defaults to @samp{15}.
23193 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
23194 Number which specifies the time-to-live, in minutes, for the cached
23195 version of the repository about page.
23197 Defaults to @samp{15}.
23201 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
23202 Number which specifies the time-to-live, in minutes, for the cached
23203 version of snapshots.
23205 Defaults to @samp{5}.
23209 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
23210 The maximum number of entries in the cgit cache. When set to @samp{0},
23211 caching is disabled.
23213 Defaults to @samp{0}.
23217 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
23218 Sort items in the repo list case sensitively.
23220 Defaults to @samp{#t}.
23224 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
23225 List of common prefixes which, when combined with a repository URL,
23226 generates valid clone URLs for the repository.
23228 Defaults to @samp{()}.
23232 @deftypevr {@code{cgit-configuration} parameter} list clone-url
23233 List of @code{clone-url} templates.
23235 Defaults to @samp{()}.
23239 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
23240 Command which will be invoked to format commit messages.
23242 Defaults to @samp{""}.
23246 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
23247 Flag which, when set to @samp{date}, enables strict date ordering in the
23248 commit log, and when set to @samp{topo} enables strict topological
23251 Defaults to @samp{"git log"}.
23255 @deftypevr {@code{cgit-configuration} parameter} file-object css
23256 URL which specifies the css document to include in all cgit pages.
23258 Defaults to @samp{"/share/cgit/cgit.css"}.
23262 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
23263 Specifies a command which will be invoked to format names and email
23264 address of committers, authors, and taggers, as represented in various
23265 places throughout the cgit interface.
23267 Defaults to @samp{""}.
23271 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
23272 Flag which, when set to @samp{#t}, will make cgit generate a HTML
23273 fragment suitable for embedding in other HTML pages.
23275 Defaults to @samp{#f}.
23279 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
23280 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
23281 commit history graph to the left of the commit messages in the
23282 repository log page.
23284 Defaults to @samp{#f}.
23288 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
23289 Flag which, when set to @samp{#t}, allows all filter settings to be
23290 overridden in repository-specific cgitrc files.
23292 Defaults to @samp{#f}.
23296 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
23297 Flag which, when set to @samp{#t}, allows users to follow a file in the
23300 Defaults to @samp{#f}.
23304 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
23305 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
23308 Defaults to @samp{#t}.
23312 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
23313 Flag which, when set to @samp{#t}, will make cgit generate extra links
23314 "summary", "commit", "tree" for each repo in the repository index.
23316 Defaults to @samp{#f}.
23320 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
23321 Flag which, when set to @samp{#t}, will make cgit display the owner of
23322 each repo in the repository index.
23324 Defaults to @samp{#t}.
23328 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
23329 Flag which, when set to @samp{#t}, will make cgit print the number of
23330 modified files for each commit on the repository log page.
23332 Defaults to @samp{#f}.
23336 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
23337 Flag which, when set to @samp{#t}, will make cgit print the number of
23338 added and removed lines for each commit on the repository log page.
23340 Defaults to @samp{#f}.
23344 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
23345 Flag which, when set to @code{#t}, will make cgit display remote
23346 branches in the summary and refs views.
23348 Defaults to @samp{#f}.
23352 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
23353 Flag which, when set to @code{1}, will make cgit use the subject of the
23354 parent commit as link text when generating links to parent commits in
23357 Defaults to @samp{#f}.
23361 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
23362 Flag which, when set to @samp{#t}, will make cgit use the subject of the
23363 parent commit as link text when generating links to parent commits in
23366 Defaults to @samp{#f}.
23370 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
23371 Flag which, when set to @samp{#t}, will make cgit generate linenumber
23372 links for plaintext blobs printed in the tree view.
23374 Defaults to @samp{#t}.
23378 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
23379 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
23380 set any repo specific settings.
23382 Defaults to @samp{#f}.
23386 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
23387 URL used as link to a shortcut icon for cgit.
23389 Defaults to @samp{"/favicon.ico"}.
23393 @deftypevr {@code{cgit-configuration} parameter} string footer
23394 The content of the file specified with this option will be included
23395 verbatim at the bottom of all pages (i.e.@: it replaces the standard
23396 "generated by..."@: message).
23398 Defaults to @samp{""}.
23402 @deftypevr {@code{cgit-configuration} parameter} string head-include
23403 The content of the file specified with this option will be included
23404 verbatim in the HTML HEAD section on all pages.
23406 Defaults to @samp{""}.
23410 @deftypevr {@code{cgit-configuration} parameter} string header
23411 The content of the file specified with this option will be included
23412 verbatim at the top of all pages.
23414 Defaults to @samp{""}.
23418 @deftypevr {@code{cgit-configuration} parameter} file-object include
23419 Name of a configfile to include before the rest of the current config-
23422 Defaults to @samp{""}.
23426 @deftypevr {@code{cgit-configuration} parameter} string index-header
23427 The content of the file specified with this option will be included
23428 verbatim above the repository index.
23430 Defaults to @samp{""}.
23434 @deftypevr {@code{cgit-configuration} parameter} string index-info
23435 The content of the file specified with this option will be included
23436 verbatim below the heading on the repository index page.
23438 Defaults to @samp{""}.
23442 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
23443 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
23444 in the servers timezone.
23446 Defaults to @samp{#f}.
23450 @deftypevr {@code{cgit-configuration} parameter} file-object logo
23451 URL which specifies the source of an image which will be used as a logo
23454 Defaults to @samp{"/share/cgit/cgit.png"}.
23458 @deftypevr {@code{cgit-configuration} parameter} string logo-link
23459 URL loaded when clicking on the cgit logo image.
23461 Defaults to @samp{""}.
23465 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
23466 Command which will be invoked to format the Owner column of the main
23469 Defaults to @samp{""}.
23473 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
23474 Number of items to display in atom feeds view.
23476 Defaults to @samp{10}.
23480 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
23481 Number of entries to list per page in "log" view.
23483 Defaults to @samp{50}.
23487 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
23488 Number of commit message characters to display in "log" view.
23490 Defaults to @samp{80}.
23494 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
23495 Specifies the number of entries to list per page on the repository index
23498 Defaults to @samp{50}.
23502 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
23503 Specifies the maximum number of repo description characters to display
23504 on the repository index page.
23506 Defaults to @samp{80}.
23510 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
23511 Specifies the maximum size of a blob to display HTML for in KBytes.
23513 Defaults to @samp{0}.
23517 @deftypevr {@code{cgit-configuration} parameter} string max-stats
23518 Maximum statistics period. Valid values are @samp{week},@samp{month},
23519 @samp{quarter} and @samp{year}.
23521 Defaults to @samp{""}.
23525 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
23526 Mimetype for the specified filename extension.
23528 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
23529 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
23530 "image/png") (svg "image/svg+xml"))}.
23534 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
23535 Specifies the file to use for automatic mimetype lookup.
23537 Defaults to @samp{""}.
23541 @deftypevr {@code{cgit-configuration} parameter} string module-link
23542 Text which will be used as the formatstring for a hyperlink when a
23543 submodule is printed in a directory listing.
23545 Defaults to @samp{""}.
23549 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
23550 If set to the value @samp{#t} caching will be disabled.
23552 Defaults to @samp{#f}.
23556 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
23557 If set to @samp{#t} showing full author email addresses will be
23560 Defaults to @samp{#f}.
23564 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
23565 Flag which, when set to @samp{#t}, will make cgit omit the standard
23566 header on all pages.
23568 Defaults to @samp{#f}.
23572 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
23573 A list of subdirectories inside of @code{repository-directory}, relative
23574 to it, that should loaded as Git repositories. An empty list means that
23575 all subdirectories will be loaded.
23577 Defaults to @samp{()}.
23581 @deftypevr {@code{cgit-configuration} parameter} file-object readme
23582 Text which will be used as default value for @code{cgit-repo-readme}.
23584 Defaults to @samp{""}.
23588 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
23589 If set to @code{#t} and @code{repository-directory} is enabled, if any
23590 repositories are found with a suffix of @code{.git}, this suffix will be
23591 removed for the URL and name.
23593 Defaults to @samp{#f}.
23597 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
23598 Maximum number of files to consider when detecting renames.
23600 Defaults to @samp{-1}.
23604 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
23605 The way in which repositories in each section are sorted.
23607 Defaults to @samp{""}.
23611 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
23612 Text used as content for the @code{robots} meta-tag.
23614 Defaults to @samp{("noindex" "nofollow")}.
23618 @deftypevr {@code{cgit-configuration} parameter} string root-desc
23619 Text printed below the heading on the repository index page.
23621 Defaults to @samp{"a fast webinterface for the git dscm"}.
23625 @deftypevr {@code{cgit-configuration} parameter} string root-readme
23626 The content of the file specified with this option will be included
23627 verbatim below thef "about" link on the repository index page.
23629 Defaults to @samp{""}.
23633 @deftypevr {@code{cgit-configuration} parameter} string root-title
23634 Text printed as heading on the repository index page.
23636 Defaults to @samp{""}.
23640 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
23641 If set to @samp{#t} and repository-directory is enabled,
23642 repository-directory will recurse into directories whose name starts
23643 with a period. Otherwise, repository-directory will stay away from such
23644 directories, considered as "hidden". Note that this does not apply to
23645 the ".git" directory in non-bare repos.
23647 Defaults to @samp{#f}.
23651 @deftypevr {@code{cgit-configuration} parameter} list snapshots
23652 Text which specifies the default set of snapshot formats that cgit
23653 generates links for.
23655 Defaults to @samp{()}.
23659 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
23660 Name of the directory to scan for repositories (represents
23663 Defaults to @samp{"/srv/git"}.
23667 @deftypevr {@code{cgit-configuration} parameter} string section
23668 The name of the current repository section - all repositories defined
23669 after this option will inherit the current section name.
23671 Defaults to @samp{""}.
23675 @deftypevr {@code{cgit-configuration} parameter} string section-sort
23676 Flag which, when set to @samp{1}, will sort the sections on the
23677 repository listing by name.
23679 Defaults to @samp{""}.
23683 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
23684 A number which, if defined prior to repository-directory, specifies how
23685 many path elements from each repo path to use as a default section name.
23687 Defaults to @samp{0}.
23691 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
23692 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
23695 Defaults to @samp{#f}.
23699 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
23700 Specifies a command which will be invoked to format plaintext blobs in
23703 Defaults to @samp{""}.
23707 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
23708 Specifies the number of branches to display in the repository "summary"
23711 Defaults to @samp{10}.
23715 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
23716 Specifies the number of log entries to display in the repository
23719 Defaults to @samp{10}.
23723 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
23724 Specifies the number of tags to display in the repository "summary"
23727 Defaults to @samp{10}.
23731 @deftypevr {@code{cgit-configuration} parameter} string strict-export
23732 Filename which, if specified, needs to be present within the repository
23733 for cgit to allow access to that repository.
23735 Defaults to @samp{""}.
23739 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
23740 URL which, if specified, will be used as root for all cgit links.
23742 Defaults to @samp{"/"}.
23746 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
23747 A list of @dfn{cgit-repo} records to use with config.
23749 Defaults to @samp{()}.
23751 Available @code{repository-cgit-configuration} fields are:
23753 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
23754 A mask of snapshot formats for this repo that cgit generates links for,
23755 restricted by the global @code{snapshots} setting.
23757 Defaults to @samp{()}.
23761 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
23762 Override the default @code{source-filter}.
23764 Defaults to @samp{""}.
23768 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
23769 The relative URL used to access the repository.
23771 Defaults to @samp{""}.
23775 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
23776 Override the default @code{about-filter}.
23778 Defaults to @samp{""}.
23782 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
23783 Flag which, when set to @samp{age}, enables date ordering in the branch
23784 ref list, and when set to @samp{name} enables ordering by branch name.
23786 Defaults to @samp{""}.
23790 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
23791 A list of URLs which can be used to clone repo.
23793 Defaults to @samp{()}.
23797 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
23798 Override the default @code{commit-filter}.
23800 Defaults to @samp{""}.
23804 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
23805 Flag which, when set to @samp{date}, enables strict date ordering in the
23806 commit log, and when set to @samp{topo} enables strict topological
23809 Defaults to @samp{""}.
23813 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
23814 The name of the default branch for this repository. If no such branch
23815 exists in the repository, the first branch name (when sorted) is used as
23816 default instead. By default branch pointed to by HEAD, or "master" if
23817 there is no suitable HEAD.
23819 Defaults to @samp{""}.
23823 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
23824 The value to show as repository description.
23826 Defaults to @samp{""}.
23830 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
23831 The value to show as repository homepage.
23833 Defaults to @samp{""}.
23837 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
23838 Override the default @code{email-filter}.
23840 Defaults to @samp{""}.
23844 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
23845 A flag which can be used to disable the global setting
23846 @code{enable-commit-graph?}.
23848 Defaults to @samp{disabled}.
23852 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
23853 A flag which can be used to disable the global setting
23854 @code{enable-log-filecount?}.
23856 Defaults to @samp{disabled}.
23860 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
23861 A flag which can be used to disable the global setting
23862 @code{enable-log-linecount?}.
23864 Defaults to @samp{disabled}.
23868 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
23869 Flag which, when set to @code{#t}, will make cgit display remote
23870 branches in the summary and refs views.
23872 Defaults to @samp{disabled}.
23876 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
23877 A flag which can be used to override the global setting
23878 @code{enable-subject-links?}.
23880 Defaults to @samp{disabled}.
23884 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
23885 A flag which can be used to override the global setting
23886 @code{enable-html-serving?}.
23888 Defaults to @samp{disabled}.
23892 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
23893 Flag which, when set to @code{#t}, hides the repository from the
23896 Defaults to @samp{#f}.
23900 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
23901 Flag which, when set to @samp{#t}, ignores the repository.
23903 Defaults to @samp{#f}.
23907 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
23908 URL which specifies the source of an image which will be used as a logo
23909 on this repo’s pages.
23911 Defaults to @samp{""}.
23915 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
23916 URL loaded when clicking on the cgit logo image.
23918 Defaults to @samp{""}.
23922 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
23923 Override the default @code{owner-filter}.
23925 Defaults to @samp{""}.
23929 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
23930 Text which will be used as the formatstring for a hyperlink when a
23931 submodule is printed in a directory listing. The arguments for the
23932 formatstring are the path and SHA1 of the submodule commit.
23934 Defaults to @samp{""}.
23938 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
23939 Text which will be used as the formatstring for a hyperlink when a
23940 submodule with the specified subdirectory path is printed in a directory
23943 Defaults to @samp{()}.
23947 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
23948 Override the default maximum statistics period.
23950 Defaults to @samp{""}.
23954 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
23955 The value to show as repository name.
23957 Defaults to @samp{""}.
23961 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
23962 A value used to identify the owner of the repository.
23964 Defaults to @samp{""}.
23968 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
23969 An absolute path to the repository directory.
23971 Defaults to @samp{""}.
23975 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
23976 A path (relative to repo) which specifies a file to include verbatim as
23977 the "About" page for this repo.
23979 Defaults to @samp{""}.
23983 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
23984 The name of the current repository section - all repositories defined
23985 after this option will inherit the current section name.
23987 Defaults to @samp{""}.
23991 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
23992 Extra options will be appended to cgitrc file.
23994 Defaults to @samp{()}.
24000 @deftypevr {@code{cgit-configuration} parameter} list extra-options
24001 Extra options will be appended to cgitrc file.
24003 Defaults to @samp{()}.
24008 @c %end of fragment
24010 However, it could be that you just want to get a @code{cgitrc} up and
24011 running. In that case, you can pass an @code{opaque-cgit-configuration}
24012 as a record to @code{cgit-service-type}. As its name indicates, an
24013 opaque configuration does not have easy reflective capabilities.
24015 Available @code{opaque-cgit-configuration} fields are:
24017 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
24021 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
24022 The contents of the @code{cgitrc}, as a string.
24025 For example, if your @code{cgitrc} is just the empty string, you
24026 could instantiate a cgit service like this:
24029 (service cgit-service-type
24030 (opaque-cgit-configuration
24034 @subsubheading Gitolite Service
24036 @cindex Gitolite service
24037 @cindex Git, hosting
24038 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
24039 repositories on a central server.
24041 Gitolite can handle multiple repositories and users, and supports flexible
24042 configuration of the permissions for the users on the repositories.
24044 The following example will configure Gitolite using the default @code{git}
24045 user, and the provided SSH public key.
24048 (service gitolite-service-type
24049 (gitolite-configuration
24050 (admin-pubkey (plain-file
24052 "ssh-rsa AAAA... guix@@example.com"))))
24055 Gitolite is configured through a special admin repository which you can clone,
24056 for example, if you setup Gitolite on @code{example.com}, you would run the
24057 following command to clone the admin repository.
24060 git clone git@@example.com:gitolite-admin
24063 When the Gitolite service is activated, the provided @code{admin-pubkey} will
24064 be inserted in to the @file{keydir} directory in the gitolite-admin
24065 repository. If this results in a change in the repository, it will be
24066 committed using the message ``gitolite setup by GNU Guix''.
24068 @deftp {Data Type} gitolite-configuration
24069 Data type representing the configuration for @code{gitolite-service-type}.
24072 @item @code{package} (default: @var{gitolite})
24073 Gitolite package to use.
24075 @item @code{user} (default: @var{git})
24076 User to use for Gitolite. This will be user that you use when accessing
24079 @item @code{group} (default: @var{git})
24080 Group to use for Gitolite.
24082 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
24083 Directory in which to store the Gitolite configuration and repositories.
24085 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
24086 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
24087 representing the configuration for Gitolite.
24089 @item @code{admin-pubkey} (default: @var{#f})
24090 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
24091 setup Gitolite. This will be inserted in to the @file{keydir} directory
24092 within the gitolite-admin repository.
24094 To specify the SSH key as a string, use the @code{plain-file} function.
24097 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
24103 @deftp {Data Type} gitolite-rc-file
24104 Data type representing the Gitolite RC file.
24107 @item @code{umask} (default: @code{#o0077})
24108 This controls the permissions Gitolite sets on the repositories and their
24111 A value like @code{#o0027} will give read access to the group used by Gitolite
24112 (by default: @code{git}). This is necessary when using Gitolite with software
24113 like cgit or gitweb.
24115 @item @code{git-config-keys} (default: @code{""})
24116 Gitolite allows you to set git config values using the "config" keyword. This
24117 setting allows control over the config keys to accept.
24119 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
24120 Set the role names allowed to be used by users running the perms command.
24122 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
24123 This setting controls the commands and features to enable within Gitolite.
24129 @node Game Services
24130 @subsection Game Services
24132 @subsubheading The Battle for Wesnoth Service
24134 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
24135 based tactical strategy game, with several single player campaigns, and
24136 multiplayer games (both networked and local).
24138 @defvar {Scheme Variable} wesnothd-service-type
24139 Service type for the wesnothd service. Its value must be a
24140 @code{wesnothd-configuration} object. To run wesnothd in the default
24141 configuration, instantiate it as:
24144 (service wesnothd-service-type)
24148 @deftp {Data Type} wesnothd-configuration
24149 Data type representing the configuration of @command{wesnothd}.
24152 @item @code{package} (default: @code{wesnoth-server})
24153 The wesnoth server package to use.
24155 @item @code{port} (default: @code{15000})
24156 The port to bind the server to.
24160 @node Miscellaneous Services
24161 @subsection Miscellaneous Services
24163 @cindex fingerprint
24164 @subsubheading Fingerprint Service
24166 The @code{(gnu services authentication)} module provides a DBus service to
24167 read and identify fingerprints via a fingerprint sensor.
24169 @defvr {Scheme Variable} fprintd-service-type
24170 The service type for @command{fprintd}, which provides the fingerprint
24171 reading capability.
24174 (service fprintd-service-type)
24179 @subsubheading System Control Service
24181 The @code{(gnu services sysctl)} provides a service to configure kernel
24182 parameters at boot.
24184 @defvr {Scheme Variable} sysctl-service-type
24185 The service type for @command{sysctl}, which modifies kernel parameters
24186 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
24190 (service sysctl-service-type
24191 (sysctl-configuration
24192 (settings '(("net.ipv4.ip_forward" . "1")))))
24196 @deftp {Data Type} sysctl-configuration
24197 The data type representing the configuration of @command{sysctl}.
24200 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
24201 The @command{sysctl} executable to use.
24203 @item @code{settings} (default: @code{'()})
24204 An association list specifies kernel parameters and their values.
24209 @subsubheading PC/SC Smart Card Daemon Service
24211 The @code{(gnu services security-token)} module provides the following service
24212 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
24213 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
24214 manager that coordinates communications with smart card readers, smart cards
24215 and cryptographic tokens that are connected to the system.
24217 @defvr {Scheme Variable} pcscd-service-type
24218 Service type for the @command{pcscd} service. Its value must be a
24219 @code{pcscd-configuration} object. To run pcscd in the default
24220 configuration, instantiate it as:
24223 (service pcscd-service-type)
24227 @deftp {Data Type} pcscd-configuration
24228 The data type representing the configuration of @command{pcscd}.
24231 @item @code{pcsc-lite} (default: @code{pcsc-lite})
24232 The pcsc-lite package that provides pcscd.
24233 @item @code{usb-drivers} (default: @code{(list ccid)})
24234 List of packages that provide USB drivers to pcscd. Drivers are expected to be
24235 under @file{pcsc/drivers} in the store directory of the package.
24240 @subsubheading Lirc Service
24242 The @code{(gnu services lirc)} module provides the following service.
24244 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
24245 [#:device #f] [#:driver #f] [#:config-file #f] @
24246 [#:extra-options '()]
24247 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
24248 decodes infrared signals from remote controls.
24250 Optionally, @var{device}, @var{driver} and @var{config-file}
24251 (configuration file name) may be specified. See @command{lircd} manual
24254 Finally, @var{extra-options} is a list of additional command-line options
24255 passed to @command{lircd}.
24259 @subsubheading Spice Service
24261 The @code{(gnu services spice)} module provides the following service.
24263 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
24264 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
24265 that enables sharing the clipboard with a vm and setting the guest display
24266 resolution when the graphical console window resizes.
24269 @cindex inputattach
24270 @subsubheading inputattach Service
24272 @cindex tablet input, for Xorg
24273 @cindex touchscreen input, for Xorg
24274 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
24275 use input devices such as Wacom tablets, touchscreens, or joysticks with the
24276 Xorg display server.
24278 @deffn {Scheme Variable} inputattach-service-type
24279 Type of a service that runs @command{inputattach} on a device and
24280 dispatches events from it.
24283 @deftp {Data Type} inputattach-configuration
24285 @item @code{device-type} (default: @code{"wacom"})
24286 The type of device to connect to. Run @command{inputattach --help}, from the
24287 @code{inputattach} package, to see the list of supported device types.
24289 @item @code{device} (default: @code{"/dev/ttyS0"})
24290 The device file to connect to the device.
24292 @item @code{log-file} (default: @code{#f})
24293 If true, this must be the name of a file to log messages to.
24297 @subsection Dictionary Services
24299 The @code{(gnu services dict)} module provides the following service:
24301 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
24302 Return a service that runs the @command{dicod} daemon, an implementation
24303 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
24305 The optional @var{config} argument specifies the configuration for
24306 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
24307 default it serves the GNU Collaborative International Dictonary of English.
24309 You can add @command{open localhost} to your @file{~/.dico} file to make
24310 @code{localhost} the default server for @command{dico} client
24311 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
24314 @deftp {Data Type} dicod-configuration
24315 Data type representing the configuration of dicod.
24318 @item @code{dico} (default: @var{dico})
24319 Package object of the GNU Dico dictionary server.
24321 @item @code{interfaces} (default: @var{'("localhost")})
24322 This is the list of IP addresses and ports and possibly socket file
24323 names to listen to (@pxref{Server Settings, @code{listen} directive,,
24324 dico, GNU Dico Manual}).
24326 @item @code{handlers} (default: @var{'()})
24327 List of @code{<dicod-handler>} objects denoting handlers (module instances).
24329 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
24330 List of @code{<dicod-database>} objects denoting dictionaries to be served.
24334 @deftp {Data Type} dicod-handler
24335 Data type representing a dictionary handler (module instance).
24339 Name of the handler (module instance).
24341 @item @code{module} (default: @var{#f})
24342 Name of the dicod module of the handler (instance). If it is @code{#f},
24343 the module has the same name as the handler.
24344 (@pxref{Modules,,, dico, GNU Dico Manual}).
24346 @item @code{options}
24347 List of strings or gexps representing the arguments for the module handler
24351 @deftp {Data Type} dicod-database
24352 Data type representing a dictionary database.
24356 Name of the database, will be used in DICT commands.
24358 @item @code{handler}
24359 Name of the dicod handler (module instance) used by this database
24360 (@pxref{Handlers,,, dico, GNU Dico Manual}).
24362 @item @code{complex?} (default: @var{#f})
24363 Whether the database configuration complex. The complex configuration
24364 will need a corresponding @code{<dicod-handler>} object, otherwise not.
24366 @item @code{options}
24367 List of strings or gexps representing the arguments for the database
24368 (@pxref{Databases,,, dico, GNU Dico Manual}).
24372 @defvr {Scheme Variable} %dicod-database:gcide
24373 A @code{<dicod-database>} object serving the GNU Collaborative International
24374 Dictionary of English using the @code{gcide} package.
24377 The following is an example @code{dicod-service} configuration.
24380 (dicod-service #:config
24381 (dicod-configuration
24382 (handlers (list (dicod-handler
24386 (list #~(string-append "dbdir=" #$wordnet))))))
24387 (databases (list (dicod-database
24390 (handler "wordnet")
24391 (options '("database=wn")))
24392 %dicod-database:gcide))))
24396 @subsubheading Docker Service
24398 The @code{(gnu services docker)} module provides the following services.
24400 @defvr {Scheme Variable} docker-service-type
24402 This is the type of the service that runs @url{https://www.docker.com,Docker},
24403 a daemon that can execute application bundles (sometimes referred to as
24404 ``containers'') in isolated environments.
24408 @deftp {Data Type} docker-configuration
24409 This is the data type representing the configuration of Docker and Containerd.
24413 @item @code{package} (default: @code{docker})
24414 The Docker package to use.
24416 @item @code{containerd} (default: @var{containerd})
24417 The Containerd package to use.
24423 @subsubheading Auditd Service
24425 The @code{(gnu services auditd)} module provides the following service.
24427 @defvr {Scheme Variable} auditd-service-type
24429 This is the type of the service that runs
24430 @url{https://people.redhat.com/sgrubb/audit/,auditd},
24431 a daemon that tracks security-relevant information on your system.
24433 Examples of things that can be tracked:
24443 Failed login attempts
24450 @command{auditctl} from the @code{audit} package can be used in order
24451 to add or remove events to be tracked (until the next reboot).
24452 In order to permanently track events, put the command line arguments
24453 of auditctl into @file{/etc/audit/audit.rules}.
24454 @command{aureport} from the @code{audit} package can be used in order
24455 to view a report of all recorded events.
24456 The audit daemon usually logs into the directory @file{/var/log/audit}.
24460 @deftp {Data Type} auditd-configuration
24461 This is the data type representing the configuration of auditd.
24465 @item @code{audit} (default: @code{audit})
24466 The audit package to use.
24471 @defvr {Scheme Variable} singularity-service-type
24472 This is the type of the service that allows you to run
24473 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
24474 create and run application bundles (aka. ``containers''). The value for this
24475 service is the Singularity package to use.
24477 The service does not install a daemon; instead, it installs helper programs as
24478 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
24479 @command{singularity run} and similar commands.
24483 @subsubheading Nix service
24485 The @code{(gnu services nix)} module provides the following service.
24487 @defvr {Scheme Variable} nix-service-type
24489 This is the type of the service that runs build daemon of the
24490 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
24494 (use-modules (gnu))
24495 (use-service-modules nix)
24496 (use-package-modules package-management)
24500 (packages (append (list nix)
24503 (services (append (list (service nix-service-type))
24507 After @command{guix system reconfigure} configure Nix for your user:
24510 @item Add a Nix channel and update it. See
24511 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
24513 @item Create a symlink to your profile and activate Nix profile:
24517 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
24518 $ source /run/current-system/profile/etc/profile.d/nix.sh
24523 @node Setuid Programs
24524 @section Setuid Programs
24526 @cindex setuid programs
24527 Some programs need to run with ``root'' privileges, even when they are
24528 launched by unprivileged users. A notorious example is the
24529 @command{passwd} program, which users can run to change their
24530 password, and which needs to access the @file{/etc/passwd} and
24531 @file{/etc/shadow} files---something normally restricted to root, for
24532 obvious security reasons. To address that, these executables are
24533 @dfn{setuid-root}, meaning that they always run with root privileges
24534 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
24535 for more info about the setuid mechanism.)
24537 The store itself @emph{cannot} contain setuid programs: that would be a
24538 security issue since any user on the system can write derivations that
24539 populate the store (@pxref{The Store}). Thus, a different mechanism is
24540 used: instead of changing the setuid bit directly on files that are in
24541 the store, we let the system administrator @emph{declare} which programs
24542 should be setuid root.
24544 The @code{setuid-programs} field of an @code{operating-system}
24545 declaration contains a list of G-expressions denoting the names of
24546 programs to be setuid-root (@pxref{Using the Configuration System}).
24547 For instance, the @command{passwd} program, which is part of the Shadow
24548 package, can be designated by this G-expression (@pxref{G-Expressions}):
24551 #~(string-append #$shadow "/bin/passwd")
24554 A default set of setuid programs is defined by the
24555 @code{%setuid-programs} variable of the @code{(gnu system)} module.
24557 @defvr {Scheme Variable} %setuid-programs
24558 A list of G-expressions denoting common programs that are setuid-root.
24560 The list includes commands such as @command{passwd}, @command{ping},
24561 @command{su}, and @command{sudo}.
24564 Under the hood, the actual setuid programs are created in the
24565 @file{/run/setuid-programs} directory at system activation time. The
24566 files in this directory refer to the ``real'' binaries, which are in the
24569 @node X.509 Certificates
24570 @section X.509 Certificates
24572 @cindex HTTPS, certificates
24573 @cindex X.509 certificates
24575 Web servers available over HTTPS (that is, HTTP over the transport-layer
24576 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
24577 that the client can then use to @emph{authenticate} the server. To do
24578 that, clients verify that the server's certificate is signed by a
24579 so-called @dfn{certificate authority} (CA). But to verify the CA's
24580 signature, clients must have first acquired the CA's certificate.
24582 Web browsers such as GNU@tie{}IceCat include their own set of CA
24583 certificates, such that they are able to verify CA signatures
24586 However, most other programs that can talk HTTPS---@command{wget},
24587 @command{git}, @command{w3m}, etc.---need to be told where CA
24588 certificates can be found.
24590 @cindex @code{nss-certs}
24591 In Guix, this is done by adding a package that provides certificates
24592 to the @code{packages} field of the @code{operating-system} declaration
24593 (@pxref{operating-system Reference}). Guix includes one such package,
24594 @code{nss-certs}, which is a set of CA certificates provided as part of
24595 Mozilla's Network Security Services.
24597 Note that it is @emph{not} part of @code{%base-packages}, so you need to
24598 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
24599 most applications and libraries look for certificates by default, points
24600 to the certificates installed globally.
24602 Unprivileged users, including users of Guix on a foreign distro,
24603 can also install their own certificate package in
24604 their profile. A number of environment variables need to be defined so
24605 that applications and libraries know where to find them. Namely, the
24606 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
24607 variables. Some applications add their own environment variables; for
24608 instance, the Git version control system honors the certificate bundle
24609 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
24610 would typically run something like:
24613 $ guix install nss-certs
24614 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
24615 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24616 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
24619 As another example, R requires the @code{CURL_CA_BUNDLE} environment
24620 variable to point to a certificate bundle, so you would have to run
24621 something like this:
24624 $ guix install nss-certs
24625 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24628 For other applications you may want to look up the required environment
24629 variable in the relevant documentation.
24632 @node Name Service Switch
24633 @section Name Service Switch
24635 @cindex name service switch
24637 The @code{(gnu system nss)} module provides bindings to the
24638 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
24639 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
24640 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
24641 extended with new ``name'' lookup methods for system databases, which
24642 includes host names, service names, user accounts, and more (@pxref{Name
24643 Service Switch, System Databases and Name Service Switch,, libc, The GNU
24644 C Library Reference Manual}).
24646 The NSS configuration specifies, for each system database, which lookup
24647 method is to be used, and how the various methods are chained
24648 together---for instance, under which circumstances NSS should try the
24649 next method in the list. The NSS configuration is given in the
24650 @code{name-service-switch} field of @code{operating-system} declarations
24651 (@pxref{operating-system Reference, @code{name-service-switch}}).
24654 @cindex .local, host name lookup
24655 As an example, the declaration below configures the NSS to use the
24656 @uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
24657 back-end}, which supports host name lookups over multicast DNS (mDNS)
24658 for host names ending in @code{.local}:
24661 (name-service-switch
24662 (hosts (list %files ;first, check /etc/hosts
24664 ;; If the above did not succeed, try
24665 ;; with 'mdns_minimal'.
24667 (name "mdns_minimal")
24669 ;; 'mdns_minimal' is authoritative for
24670 ;; '.local'. When it returns "not found",
24671 ;; no need to try the next methods.
24672 (reaction (lookup-specification
24673 (not-found => return))))
24675 ;; Then fall back to DNS.
24679 ;; Finally, try with the "full" 'mdns'.
24684 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
24685 contains this configuration, so you will not have to type it if all you
24686 want is to have @code{.local} host lookup working.
24688 Note that, in this case, in addition to setting the
24689 @code{name-service-switch} of the @code{operating-system} declaration,
24690 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
24691 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
24692 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
24693 to the name service cache daemon (@pxref{Base Services,
24694 @code{nscd-service}}).
24696 For convenience, the following variables provide typical NSS
24699 @defvr {Scheme Variable} %default-nss
24700 This is the default name service switch configuration, a
24701 @code{name-service-switch} object.
24704 @defvr {Scheme Variable} %mdns-host-lookup-nss
24705 This is the name service switch configuration with support for host name
24706 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
24709 The reference for name service switch configuration is given below. It
24710 is a direct mapping of the configuration file format of the C library , so
24711 please refer to the C library manual for more information (@pxref{NSS
24712 Configuration File,,, libc, The GNU C Library Reference Manual}).
24713 Compared to the configuration file format of libc NSS, it has the advantage
24714 not only of adding this warm parenthetic feel that we like, but also
24715 static checks: you will know about syntax errors and typos as soon as you
24716 run @command{guix system}.
24718 @deftp {Data Type} name-service-switch
24720 This is the data type representation the configuration of libc's name
24721 service switch (NSS). Each field below represents one of the supported
24738 The system databases handled by the NSS. Each of these fields must be a
24739 list of @code{<name-service>} objects (see below).
24743 @deftp {Data Type} name-service
24745 This is the data type representing an actual name service and the
24746 associated lookup action.
24750 A string denoting the name service (@pxref{Services in the NSS
24751 configuration,,, libc, The GNU C Library Reference Manual}).
24753 Note that name services listed here must be visible to nscd. This is
24754 achieved by passing the @code{#:name-services} argument to
24755 @code{nscd-service} the list of packages providing the needed name
24756 services (@pxref{Base Services, @code{nscd-service}}).
24759 An action specified using the @code{lookup-specification} macro
24760 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
24761 Reference Manual}). For example:
24764 (lookup-specification (unavailable => continue)
24765 (success => return))
24770 @node Initial RAM Disk
24771 @section Initial RAM Disk
24774 @cindex initial RAM disk
24775 For bootstrapping purposes, the Linux-Libre kernel is passed an
24776 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
24777 root file system as well as an initialization script. The latter is
24778 responsible for mounting the real root file system, and for loading any
24779 kernel modules that may be needed to achieve that.
24781 The @code{initrd-modules} field of an @code{operating-system}
24782 declaration allows you to specify Linux-libre kernel modules that must
24783 be available in the initrd. In particular, this is where you would list
24784 modules needed to actually drive the hard disk where your root partition
24785 is---although the default value of @code{initrd-modules} should cover
24786 most use cases. For example, assuming you need the @code{megaraid_sas}
24787 module in addition to the default modules to be able to access your root
24788 file system, you would write:
24793 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
24796 @defvr {Scheme Variable} %base-initrd-modules
24797 This is the list of kernel modules included in the initrd by default.
24800 Furthermore, if you need lower-level customization, the @code{initrd}
24801 field of an @code{operating-system} declaration allows
24802 you to specify which initrd you would like to use. The @code{(gnu
24803 system linux-initrd)} module provides three ways to build an initrd: the
24804 high-level @code{base-initrd} procedure and the low-level
24805 @code{raw-initrd} and @code{expression->initrd} procedures.
24807 The @code{base-initrd} procedure is intended to cover most common uses.
24808 For example, if you want to add a bunch of kernel modules to be loaded
24809 at boot time, you can define the @code{initrd} field of the operating
24810 system declaration like this:
24813 (initrd (lambda (file-systems . rest)
24814 ;; Create a standard initrd but set up networking
24815 ;; with the parameters QEMU expects by default.
24816 (apply base-initrd file-systems
24817 #:qemu-networking? #t
24821 The @code{base-initrd} procedure also handles common use cases that
24822 involves using the system as a QEMU guest, or as a ``live'' system with
24823 volatile root file system.
24825 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
24826 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
24827 such as trying to guess which kernel modules and packages should be included
24828 to the initrd. An example use of @code{raw-initrd} is when a user has
24829 a custom Linux kernel configuration and default kernel modules included by
24830 @code{base-initrd} are not available.
24832 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
24833 honors several options passed on the Linux kernel command line
24834 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
24835 @code{-append} option of QEMU), notably:
24838 @item --load=@var{boot}
24839 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
24840 program, once it has mounted the root file system.
24842 Guix uses this option to yield control to a boot program that runs the
24843 service activation programs and then spawns the GNU@tie{}Shepherd, the
24844 initialization system.
24846 @item --root=@var{root}
24847 Mount @var{root} as the root file system. @var{root} can be a
24848 device name like @code{/dev/sda1}, a file system label, or a file system
24851 @item --system=@var{system}
24852 Have @file{/run/booted-system} and @file{/run/current-system} point to
24855 @item modprobe.blacklist=@var{modules}@dots{}
24856 @cindex module, black-listing
24857 @cindex black list, of kernel modules
24858 Instruct the initial RAM disk as well as the @command{modprobe} command
24859 (from the kmod package) to refuse to load @var{modules}. @var{modules}
24860 must be a comma-separated list of module names---e.g.,
24861 @code{usbkbd,9pnet}.
24864 Start a read-eval-print loop (REPL) from the initial RAM disk before it
24865 tries to load kernel modules and to mount the root file system. Our
24866 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
24867 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
24868 Manual}, for more information on Guile's REPL.
24872 Now that you know all the features that initial RAM disks produced by
24873 @code{base-initrd} and @code{raw-initrd} provide,
24874 here is how to use it and customize it further.
24877 @cindex initial RAM disk
24878 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
24879 [#:linux-modules '()] [#:mapped-devices '()] @
24880 [#:keyboard-layout #f] @
24881 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
24882 Return a derivation that builds a raw initrd. @var{file-systems} is
24883 a list of file systems to be mounted by the initrd, possibly in addition to
24884 the root file system specified on the kernel command line via @code{--root}.
24885 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
24886 @var{mapped-devices} is a list of device mappings to realize before
24887 @var{file-systems} are mounted (@pxref{Mapped Devices}).
24888 @var{helper-packages} is a list of packages to be copied in the initrd. It may
24889 include @code{e2fsck/static} or other packages needed by the initrd to check
24890 the root file system.
24892 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24893 the desired console keyboard layout. This is done before @var{mapped-devices}
24894 are set up and before @var{file-systems} are mounted such that, should the
24895 user need to enter a passphrase or use the REPL, this happens using the
24896 intended keyboard layout.
24898 When @var{qemu-networking?} is true, set up networking with the standard QEMU
24899 parameters. When @var{virtio?} is true, load additional modules so that the
24900 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
24902 When @var{volatile-root?} is true, the root file system is writable but any changes
24906 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
24907 [#:mapped-devices '()] [#:keyboard-layout #f] @
24908 [#:qemu-networking? #f] [#:volatile-root? #f] @
24909 [#:linux-modules '()]
24910 Return as a file-like object a generic initrd, with kernel
24911 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
24912 mounted by the initrd, possibly in addition to the root file system specified
24913 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
24914 mappings to realize before @var{file-systems} are mounted.
24916 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24917 the desired console keyboard layout. This is done before @var{mapped-devices}
24918 are set up and before @var{file-systems} are mounted such that, should the
24919 user need to enter a passphrase or use the REPL, this happens using the
24920 intended keyboard layout.
24922 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
24924 The initrd is automatically populated with all the kernel modules necessary
24925 for @var{file-systems} and for the given options. Additional kernel
24926 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
24927 loaded at boot time in the order in which they appear.
24930 Needless to say, the initrds we produce and use embed a
24931 statically-linked Guile, and the initialization program is a Guile
24932 program. That gives a lot of flexibility. The
24933 @code{expression->initrd} procedure builds such an initrd, given the
24934 program to run in that initrd.
24936 @deffn {Scheme Procedure} expression->initrd @var{exp} @
24937 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
24938 Return as a file-like object a Linux initrd (a gzipped cpio archive)
24939 containing @var{guile} and that evaluates @var{exp}, a G-expression,
24940 upon booting. All the derivations referenced by @var{exp} are
24941 automatically copied to the initrd.
24944 @node Bootloader Configuration
24945 @section Bootloader Configuration
24948 @cindex boot loader
24950 The operating system supports multiple bootloaders. The bootloader is
24951 configured using @code{bootloader-configuration} declaration. All the
24952 fields of this structure are bootloader agnostic except for one field,
24953 @code{bootloader} that indicates the bootloader to be configured and
24956 Some of the bootloaders do not honor every field of
24957 @code{bootloader-configuration}. For instance, the extlinux
24958 bootloader does not support themes and thus ignores the @code{theme}
24961 @deftp {Data Type} bootloader-configuration
24962 The type of a bootloader configuration declaration.
24966 @item @code{bootloader}
24967 @cindex EFI, bootloader
24968 @cindex UEFI, bootloader
24969 @cindex BIOS, bootloader
24970 The bootloader to use, as a @code{bootloader} object. For now
24971 @code{grub-bootloader}, @code{grub-efi-bootloader},
24972 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
24974 @vindex grub-efi-bootloader
24975 @code{grub-efi-bootloader} allows to boot on modern systems using the
24976 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
24977 use if the installation image contains a @file{/sys/firmware/efi} directory
24978 when you boot it on your system.
24980 @vindex grub-bootloader
24981 @code{grub-bootloader} allows you to boot in particular Intel-based machines
24982 in ``legacy'' BIOS mode.
24984 @cindex ARM, bootloaders
24985 @cindex AArch64, bootloaders
24986 Available bootloaders are described in @code{(gnu bootloader @dots{})}
24987 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
24988 of bootloaders for a wide range of ARM and AArch64 systems, using the
24989 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
24991 @item @code{target}
24992 This is a string denoting the target onto which to install the
24995 The interpretation depends on the bootloader in question. For
24996 @code{grub-bootloader}, for example, it should be a device name understood by
24997 the bootloader @command{installer} command, such as @code{/dev/sda} or
24998 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
24999 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
25000 system, usually @file{/boot/efi}.
25002 @item @code{menu-entries} (default: @code{()})
25003 A possibly empty list of @code{menu-entry} objects (see below), denoting
25004 entries to appear in the bootloader menu, in addition to the current
25005 system entry and the entry pointing to previous system generations.
25007 @item @code{default-entry} (default: @code{0})
25008 The index of the default boot menu entry. Index 0 is for the entry of the
25011 @item @code{timeout} (default: @code{5})
25012 The number of seconds to wait for keyboard input before booting. Set to
25013 0 to boot immediately, and to -1 to wait indefinitely.
25015 @cindex keyboard layout, for the bootloader
25016 @item @code{keyboard-layout} (default: @code{#f})
25017 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
25018 layout, usually US@tie{}English (``qwerty'').
25020 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
25024 This option is currently ignored by bootloaders other than @code{grub} and
25028 @item @code{theme} (default: @var{#f})
25029 The bootloader theme object describing the theme to use. If no theme
25030 is provided, some bootloaders might use a default theme, that's true
25033 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
25034 The output terminals used for the bootloader boot menu, as a list of
25035 symbols. GRUB accepts the values: @code{console}, @code{serial},
25036 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
25037 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
25038 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
25039 configuration,,, grub,GNU GRUB manual}).
25041 @item @code{terminal-inputs} (default: @code{'()})
25042 The input terminals used for the bootloader boot menu, as a list of
25043 symbols. For GRUB, the default is the native platform terminal as
25044 determined at run-time. GRUB accepts the values: @code{console},
25045 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
25046 @code{usb_keyboard}. This field corresponds to the GRUB variable
25047 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
25050 @item @code{serial-unit} (default: @code{#f})
25051 The serial unit used by the bootloader, as an integer from 0 to 3.
25052 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
25053 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
25055 @item @code{serial-speed} (default: @code{#f})
25056 The speed of the serial interface, as an integer. For GRUB, the
25057 default value is chosen at run-time; currently GRUB chooses
25058 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
25065 Should you want to list additional boot menu entries @i{via} the
25066 @code{menu-entries} field above, you will need to create them with the
25067 @code{menu-entry} form. For example, imagine you want to be able to
25068 boot another distro (hard to imagine!), you can define a menu entry
25073 (label "The Other Distro")
25074 (linux "/boot/old/vmlinux-2.6.32")
25075 (linux-arguments '("root=/dev/sda2"))
25076 (initrd "/boot/old/initrd"))
25081 @deftp {Data Type} menu-entry
25082 The type of an entry in the bootloader menu.
25087 The label to show in the menu---e.g., @code{"GNU"}.
25090 The Linux kernel image to boot, for example:
25093 (file-append linux-libre "/bzImage")
25096 For GRUB, it is also possible to specify a device explicitly in the
25097 file path using GRUB's device naming convention (@pxref{Naming
25098 convention,,, grub, GNU GRUB manual}), for example:
25101 "(hd0,msdos1)/boot/vmlinuz"
25104 If the device is specified explicitly as above, then the @code{device}
25105 field is ignored entirely.
25107 @item @code{linux-arguments} (default: @code{()})
25108 The list of extra Linux kernel command-line arguments---e.g.,
25109 @code{("console=ttyS0")}.
25111 @item @code{initrd}
25112 A G-Expression or string denoting the file name of the initial RAM disk
25113 to use (@pxref{G-Expressions}).
25114 @item @code{device} (default: @code{#f})
25115 The device where the kernel and initrd are to be found---i.e., for GRUB,
25116 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
25118 This may be a file system label (a string), a file system UUID (a
25119 bytevector, @pxref{File Systems}), or @code{#f}, in which case
25120 the bootloader will search the device containing the file specified by
25121 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
25122 must @emph{not} be an OS device name such as @file{/dev/sda1}.
25127 @c FIXME: Write documentation once it's stable.
25128 For now only GRUB has theme support. GRUB themes are created using
25129 the @code{grub-theme} form, which is not documented yet.
25131 @defvr {Scheme Variable} %default-theme
25132 This is the default GRUB theme used by the operating system if no
25133 @code{theme} field is specified in @code{bootloader-configuration}
25136 It comes with a fancy background image displaying the GNU and Guix
25141 @node Invoking guix system
25142 @section Invoking @code{guix system}
25144 Once you have written an operating system declaration as seen in the
25145 previous section, it can be @dfn{instantiated} using the @command{guix
25146 system} command. The synopsis is:
25149 guix system @var{options}@dots{} @var{action} @var{file}
25152 @var{file} must be the name of a file containing an
25153 @code{operating-system} declaration. @var{action} specifies how the
25154 operating system is instantiated. Currently the following values are
25159 Display available service type definitions that match the given regular
25160 expressions, sorted by relevance:
25163 $ guix system search console font
25164 name: console-fonts
25165 location: gnu/services/base.scm:729:2
25166 extends: shepherd-root
25167 description: Install the given fonts on the specified ttys (fonts are
25168 + per virtual console on GNU/Linux). The value of this service is a list
25169 + of tty/font pairs like:
25171 + '(("tty1" . "LatGrkCyr-8x16"))
25175 location: gnu/services/base.scm:1048:2
25176 extends: shepherd-root
25177 description: Provide console login using the `mingetty' program.
25181 location: gnu/services/base.scm:775:2
25183 description: Provide a console log-in service as specified by its
25184 + configuration value, a `login-configuration' object.
25190 As for @command{guix package --search}, the result is written in
25191 @code{recutils} format, which makes it easy to filter the output
25192 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
25195 Build the operating system described in @var{file}, activate it, and
25196 switch to it@footnote{This action (and the related actions
25197 @code{switch-generation} and @code{roll-back}) are usable only on
25198 systems already running Guix System.}.
25200 This effects all the configuration specified in @var{file}: user
25201 accounts, system services, global package list, setuid programs, etc.
25202 The command starts system services specified in @var{file} that are not
25203 currently running; if a service is currently running this command will
25204 arrange for it to be upgraded the next time it is stopped (e.g.@: by
25205 @code{herd stop X} or @code{herd restart X}).
25207 This command creates a new generation whose number is one greater than
25208 the current generation (as reported by @command{guix system
25209 list-generations}). If that generation already exists, it will be
25210 overwritten. This behavior mirrors that of @command{guix package}
25211 (@pxref{Invoking guix package}).
25213 It also adds a bootloader menu entry for the new OS configuration,
25214 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
25215 entries for older configurations to a submenu, allowing you to choose
25216 an older system generation at boot time should you need it.
25219 @c The paragraph below refers to the problem discussed at
25220 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
25221 It is highly recommended to run @command{guix pull} once before you run
25222 @command{guix system reconfigure} for the first time (@pxref{Invoking
25223 guix pull}). Failing to do that you would see an older version of Guix
25224 once @command{reconfigure} has completed.
25227 @item switch-generation
25228 @cindex generations
25229 Switch to an existing system generation. This action atomically
25230 switches the system profile to the specified system generation. It
25231 also rearranges the system's existing bootloader menu entries. It
25232 makes the menu entry for the specified system generation the default,
25233 and it moves the entries for the other generatiors to a submenu, if
25234 supported by the bootloader being used. The next time the system
25235 boots, it will use the specified system generation.
25237 The bootloader itself is not being reinstalled when using this
25238 command. Thus, the installed bootloader is used with an updated
25239 configuration file.
25241 The target generation can be specified explicitly by its generation
25242 number. For example, the following invocation would switch to system
25246 guix system switch-generation 7
25249 The target generation can also be specified relative to the current
25250 generation with the form @code{+N} or @code{-N}, where @code{+3} means
25251 ``3 generations ahead of the current generation,'' and @code{-1} means
25252 ``1 generation prior to the current generation.'' When specifying a
25253 negative value such as @code{-1}, you must precede it with @code{--} to
25254 prevent it from being parsed as an option. For example:
25257 guix system switch-generation -- -1
25260 Currently, the effect of invoking this action is @emph{only} to switch
25261 the system profile to an existing generation and rearrange the
25262 bootloader menu entries. To actually start using the target system
25263 generation, you must reboot after running this action. In the future,
25264 it will be updated to do the same things as @command{reconfigure},
25265 like activating and deactivating services.
25267 This action will fail if the specified generation does not exist.
25270 @cindex rolling back
25271 Switch to the preceding system generation. The next time the system
25272 boots, it will use the preceding system generation. This is the inverse
25273 of @command{reconfigure}, and it is exactly the same as invoking
25274 @command{switch-generation} with an argument of @code{-1}.
25276 Currently, as with @command{switch-generation}, you must reboot after
25277 running this action to actually start using the preceding system
25280 @item delete-generations
25281 @cindex deleting system generations
25282 @cindex saving space
25283 Delete system generations, making them candidates for garbage collection
25284 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
25287 This works in the same way as @command{guix package --delete-generations}
25288 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
25289 arguments, all system generations but the current one are deleted:
25292 guix system delete-generations
25295 You can also select the generations you want to delete. The example below
25296 deletes all the system generations that are more than two month old:
25299 guix system delete-generations 2m
25302 Running this command automatically reinstalls the bootloader with an updated
25303 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
25304 longer lists the generations that have been deleted.
25307 Build the derivation of the operating system, which includes all the
25308 configuration files and programs needed to boot and run the system.
25309 This action does not actually install anything.
25312 Populate the given directory with all the files necessary to run the
25313 operating system specified in @var{file}. This is useful for first-time
25314 installations of Guix System. For instance:
25317 guix system init my-os-config.scm /mnt
25320 copies to @file{/mnt} all the store items required by the configuration
25321 specified in @file{my-os-config.scm}. This includes configuration
25322 files, packages, and so on. It also creates other essential files
25323 needed for the system to operate correctly---e.g., the @file{/etc},
25324 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
25326 This command also installs bootloader on the target specified in
25327 @file{my-os-config}, unless the @option{--no-bootloader} option was
25331 @cindex virtual machine
25333 @anchor{guix system vm}
25334 Build a virtual machine that contains the operating system declared in
25335 @var{file}, and return a script to run that virtual machine (VM).
25338 The @code{vm} action and others below
25339 can use KVM support in the Linux-libre kernel. Specifically, if the
25340 machine has hardware virtualization support, the corresponding
25341 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
25342 must exist and be readable and writable by the user and by the
25343 build users of the daemon (@pxref{Build Environment Setup}).
25346 Arguments given to the script are passed to QEMU as in the example
25347 below, which enables networking and requests 1@tie{}GiB of RAM for the
25351 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -net user
25354 The VM shares its store with the host system.
25356 Additional file systems can be shared between the host and the VM using
25357 the @code{--share} and @code{--expose} command-line options: the former
25358 specifies a directory to be shared with write access, while the latter
25359 provides read-only access to the shared directory.
25361 The example below creates a VM in which the user's home directory is
25362 accessible read-only, and where the @file{/exchange} directory is a
25363 read-write mapping of @file{$HOME/tmp} on the host:
25366 guix system vm my-config.scm \
25367 --expose=$HOME --share=$HOME/tmp=/exchange
25370 On GNU/Linux, the default is to boot directly to the kernel; this has
25371 the advantage of requiring only a very tiny root disk image since the
25372 store of the host can then be mounted.
25374 The @code{--full-boot} option forces a complete boot sequence, starting
25375 with the bootloader. This requires more disk space since a root image
25376 containing at least the kernel, initrd, and bootloader data files must
25377 be created. The @code{--image-size} option can be used to specify the
25380 @cindex System images, creation in various formats
25381 @cindex Creating system images in various formats
25384 @itemx docker-image
25385 Return a virtual machine, disk image, or Docker image of the operating
25386 system declared in @var{file} that stands alone. By default,
25387 @command{guix system} estimates the size of the image needed to store
25388 the system, but you can use the @option{--image-size} option to specify
25389 a value. Docker images are built to contain exactly what they need, so
25390 the @option{--image-size} option is ignored in the case of
25391 @code{docker-image}.
25393 You can specify the root file system type by using the
25394 @option{--file-system-type} option. It defaults to @code{ext4}.
25396 When using @code{vm-image}, the returned image is in qcow2 format, which
25397 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
25398 for more information on how to run the image in a virtual machine.
25400 When using @code{disk-image}, a raw disk image is produced; it can be
25401 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
25402 the device corresponding to a USB stick, one can copy the image to it
25403 using the following command:
25406 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
25409 When using @code{docker-image}, a Docker image is produced. Guix builds
25410 the image from scratch, not from a pre-existing Docker base image. As a
25411 result, it contains @emph{exactly} what you define in the operating
25412 system configuration file. You can then load the image and launch a
25413 Docker container using commands like the following:
25416 image_id="`docker load < guix-system-docker-image.tar.gz`"
25417 container_id="`docker create $image_id`"
25418 docker start $container_id
25421 This command starts a new Docker container from the specified image. It
25422 will boot the Guix system in the usual manner, which means it will
25423 start any services you have defined in the operating system
25424 configuration. You can get an interactive shell running in the container
25425 using @command{docker exec}:
25428 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
25431 Depending on what you run in the Docker container, it
25432 may be necessary to give the container additional permissions. For
25433 example, if you intend to build software using Guix inside of the Docker
25434 container, you may need to pass the @option{--privileged} option to
25435 @code{docker create}.
25438 Return a script to run the operating system declared in @var{file}
25439 within a container. Containers are a set of lightweight isolation
25440 mechanisms provided by the kernel Linux-libre. Containers are
25441 substantially less resource-demanding than full virtual machines since
25442 the kernel, shared objects, and other resources can be shared with the
25443 host system; this also means they provide thinner isolation.
25445 Currently, the script must be run as root in order to support more than
25446 a single user and group. The container shares its store with the host
25449 As with the @code{vm} action (@pxref{guix system vm}), additional file
25450 systems to be shared between the host and container can be specified
25451 using the @option{--share} and @option{--expose} options:
25454 guix system container my-config.scm \
25455 --expose=$HOME --share=$HOME/tmp=/exchange
25459 This option requires Linux-libre 3.19 or newer.
25464 @var{options} can contain any of the common build options (@pxref{Common
25465 Build Options}). In addition, @var{options} can contain one of the
25469 @item --expression=@var{expr}
25470 @itemx -e @var{expr}
25471 Consider the operating-system @var{expr} evaluates to.
25472 This is an alternative to specifying a file which evaluates to an
25474 This is used to generate the Guix system installer @pxref{Building the
25475 Installation Image}).
25477 @item --system=@var{system}
25478 @itemx -s @var{system}
25479 Attempt to build for @var{system} instead of the host system type.
25480 This works as per @command{guix build} (@pxref{Invoking guix build}).
25484 Return the derivation file name of the given operating system without
25487 @item --file-system-type=@var{type}
25488 @itemx -t @var{type}
25489 For the @code{disk-image} action, create a file system of the given
25490 @var{type} on the image.
25492 When this option is omitted, @command{guix system} uses @code{ext4}.
25494 @cindex ISO-9660 format
25495 @cindex CD image format
25496 @cindex DVD image format
25497 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
25498 for burning on CDs and DVDs.
25500 @item --image-size=@var{size}
25501 For the @code{vm-image} and @code{disk-image} actions, create an image
25502 of the given @var{size}. @var{size} may be a number of bytes, or it may
25503 include a unit as a suffix (@pxref{Block size, size specifications,,
25504 coreutils, GNU Coreutils}).
25506 When this option is omitted, @command{guix system} computes an estimate
25507 of the image size as a function of the size of the system declared in
25512 For the @code{container} action, allow containers to access the host network,
25513 that is, do not create a network namespace.
25515 @item --root=@var{file}
25516 @itemx -r @var{file}
25517 Make @var{file} a symlink to the result, and register it as a garbage
25520 @item --skip-checks
25521 Skip pre-installation safety checks.
25523 By default, @command{guix system init} and @command{guix system
25524 reconfigure} perform safety checks: they make sure the file systems that
25525 appear in the @code{operating-system} declaration actually exist
25526 (@pxref{File Systems}), and that any Linux kernel modules that may be
25527 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
25528 RAM Disk}). Passing this option skips these tests altogether.
25531 @cindex on-error strategy
25532 @cindex error strategy
25533 @item --on-error=@var{strategy}
25534 Apply @var{strategy} when an error occurs when reading @var{file}.
25535 @var{strategy} may be one of the following:
25538 @item nothing-special
25539 Report the error concisely and exit. This is the default strategy.
25542 Likewise, but also display a backtrace.
25545 Report the error and enter Guile's debugger. From there, you can run
25546 commands such as @code{,bt} to get a backtrace, @code{,locals} to
25547 display local variable values, and more generally inspect the state of the
25548 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
25549 a list of available debugging commands.
25553 Once you have built, configured, re-configured, and re-re-configured
25554 your Guix installation, you may find it useful to list the operating
25555 system generations available on disk---and that you can choose from the
25556 bootloader boot menu:
25560 @item list-generations
25561 List a summary of each generation of the operating system available on
25562 disk, in a human-readable way. This is similar to the
25563 @option{--list-generations} option of @command{guix package}
25564 (@pxref{Invoking guix package}).
25566 Optionally, one can specify a pattern, with the same syntax that is used
25567 in @command{guix package --list-generations}, to restrict the list of
25568 generations displayed. For instance, the following command displays
25569 generations that are up to 10 days old:
25572 $ guix system list-generations 10d
25577 The @command{guix system} command has even more to offer! The following
25578 sub-commands allow you to visualize how your system services relate to
25581 @anchor{system-extension-graph}
25584 @item extension-graph
25585 Emit in Dot/Graphviz format to standard output the @dfn{service
25586 extension graph} of the operating system defined in @var{file}
25587 (@pxref{Service Composition}, for more information on service
25593 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
25596 produces a PDF file showing the extension relations among services.
25598 @anchor{system-shepherd-graph}
25599 @item shepherd-graph
25600 Emit in Dot/Graphviz format to standard output the @dfn{dependency
25601 graph} of shepherd services of the operating system defined in
25602 @var{file}. @xref{Shepherd Services}, for more information and for an
25607 @node Invoking guix deploy
25608 @section Invoking @code{guix deploy}
25610 We've already seen @code{operating-system} declarations used to manage a
25611 machine's configuration locally. Suppose you need to configure multiple
25612 machines, though---perhaps you're managing a service on the web that's
25613 comprised of several servers. @command{guix deploy} enables you to use those
25614 same @code{operating-system} declarations to manage multiple remote hosts at
25615 once as a logical ``deployment''.
25618 The functionality described in this section is still under development
25619 and is subject to change. Get in touch with us on
25620 @email{guix-devel@@gnu.org}!
25624 guix deploy @var{file}
25627 Such an invocation will deploy the machines that the code within @var{file}
25628 evaluates to. As an example, @var{file} might contain a definition like this:
25631 ;; This is a Guix deployment of a "bare bones" setup, with
25632 ;; no X11 display server, to a machine with an SSH daemon
25633 ;; listening on localhost:2222. A configuration such as this
25634 ;; may be appropriate for virtual machine with ports
25635 ;; forwarded to the host's loopback interface.
25637 (use-service-modules networking ssh)
25638 (use-package-modules bootloaders)
25642 (host-name "gnu-deployed")
25643 (timezone "Etc/UTC")
25644 (bootloader (bootloader-configuration
25645 (bootloader grub-bootloader)
25646 (target "/dev/vda")
25647 (terminal-outputs '(console))))
25648 (file-systems (cons (file-system
25650 (device "/dev/vda1")
25652 %base-file-systems))
25654 (append (list (service dhcp-client-service-type)
25655 (service openssh-service-type
25656 (openssh-configuration
25657 (permit-root-login #t)
25658 (allow-empty-passwords? #t))))
25662 (operating-system %system)
25663 (environment managed-host-environment-type)
25664 (configuration (machine-ssh-configuration
25665 (host-name "localhost")
25666 (system "x86_64-linux")
25668 (identity "./id_rsa")
25672 The file should evaluate to a list of @var{machine} objects. This example,
25673 upon being deployed, will create a new generation on the remote system
25674 realizing the @code{operating-system} declaration @var{%system}.
25675 @var{environment} and @var{configuration} specify how the machine should be
25676 provisioned---that is, how the computing resources should be created and
25677 managed. The above example does not create any resources, as a
25678 @code{'managed-host} is a machine that is already running the Guix system and
25679 available over the network. This is a particularly simple case; a more
25680 complex deployment may involve, for example, starting virtual machines through
25681 a Virtual Private Server (VPS) provider. In such a case, a different
25682 @var{environment} type would be used.
25684 Do note that you first need to generate a key pair on the coordinator machine
25685 to allow the daemon to export signed archives of files from the store
25686 (@pxref{Invoking guix archive}).
25689 # guix archive --generate-key
25693 Each target machine must authorize the key of the master machine so that it
25694 accepts store items it receives from the coordinator:
25697 # guix archive --authorize < coordinator-public-key.txt
25700 @code{user}, in this example, specifies the name of the user account to log in
25701 as to perform the deployment. Its default value is @code{root}, but root
25702 login over SSH may be forbidden in some cases. To work around this,
25703 @command{guix deploy} can log in as an unprivileged user and employ
25704 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
25705 currently installed on the remote and can be invoked non-interactively as
25706 @code{user}. That is: the line in @code{sudoers} granting @code{user} the
25707 ability to use @code{sudo} must contain the @code{NOPASSWD} tag.
25709 @deftp {Data Type} machine
25710 This is the data type representing a single machine in a heterogeneous Guix
25714 @item @code{operating-system}
25715 The object of the operating system configuration to deploy.
25717 @item @code{environment}
25718 An @code{environment-type} describing how the machine should be provisioned.
25719 At the moment, the only supported value is
25720 @code{managed-host-environment-type}.
25722 @item @code{configuration} (default: @code{#f})
25723 An object describing the configuration for the machine's @code{environment}.
25724 If the @code{environment} has a default configuration, @code{#f} maybe used.
25725 If @code{#f} is used for an environment with no default configuration,
25726 however, an error will be thrown.
25730 @deftp {Data Type} machine-ssh-configuration
25731 This is the data type representing the SSH client parameters for a machine
25732 with an @code{environment} of @code{managed-host-environment-type}.
25735 @item @code{host-name}
25736 @item @code{build-locally?} (default: @code{#t})
25737 If false, system derivations will be built on the machine being deployed to.
25738 @item @code{system}
25739 The Nix system type describing the architecture of the machine being deployed
25740 to. This should look something like ``x86_64-linux''.
25741 @item @code{authorize?} (default: @code{#t})
25742 If true, the coordinator's signing key will be added to the remote's ACL
25744 @item @code{port} (default: @code{22})
25745 @item @code{user} (default: @code{"root"})
25746 @item @code{identity} (default: @code{#f})
25747 If specified, the path to the SSH private key to use to authenticate with the
25752 @node Running Guix in a VM
25753 @section Running Guix in a Virtual Machine
25755 @cindex virtual machine
25756 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
25758 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
25759 This image is a compressed image in QCOW format. You will first need to
25760 decompress with @command{xz -d}, and then you can pass it to an emulator such
25761 as QEMU (see below for details).
25763 This image boots the Xfce graphical environment and it contains some
25764 commonly-used tools. You can install more software in the image by running
25765 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
25766 also reconfigure the system based on its initial configuration file available
25767 as @file{/etc/config.scm} (@pxref{Using the Configuration System}).
25769 Instead of using this pre-built image, one can also build their own virtual
25770 machine image using @command{guix system vm-image} (@pxref{Invoking guix
25771 system}). The returned image is in qcow2 format, which the
25772 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
25775 If you built your own image, you must copy it out of the store
25776 (@pxref{The Store}) and give yourself permission to write to the copy
25777 before you can use it. When invoking QEMU, you must choose a system
25778 emulator that is suitable for your hardware platform. Here is a minimal
25779 QEMU invocation that will boot the result of @command{guix system
25780 vm-image} on x86_64 hardware:
25783 $ qemu-system-x86_64 \
25784 -net user -net nic,model=virtio \
25785 -enable-kvm -m 1024 \
25786 -device virtio-blk,drive=myhd \
25787 -drive if=none,file=/tmp/qemu-image,id=myhd
25790 Here is what each of these options means:
25793 @item qemu-system-x86_64
25794 This specifies the hardware platform to emulate. This should match the
25798 Enable the unprivileged user-mode network stack. The guest OS can
25799 access the host but not vice versa. This is the simplest way to get the
25802 @item -net nic,model=virtio
25803 You must create a network interface of a given model. If you do not
25804 create a NIC, the boot will fail. Assuming your hardware platform is
25805 x86_64, you can get a list of available NIC models by running
25806 @command{qemu-system-x86_64 -net nic,model=help}.
25809 If your system has hardware virtualization extensions, enabling the
25810 virtual machine support (KVM) of the Linux kernel will make things run
25813 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
25815 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
25816 which may be insufficient for some operations.
25818 @item -device virtio-blk,drive=myhd
25819 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
25820 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
25821 better performance than if it were emulating a complete disk drive. See the
25822 QEMU and KVM documentation for more info.
25824 @item -drive if=none,file=/tmp/qemu-image,id=myhd
25825 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
25826 the ``myhd'' drive.
25829 The default @command{run-vm.sh} script that is returned by an invocation of
25830 @command{guix system vm} does not add a @command{-net user} flag by default.
25831 To get network access from within the vm add the @code{(dhcp-client-service)}
25832 to your system definition and start the VM using
25833 @command{`guix system vm config.scm` -net user}. An important caveat of using
25834 @command{-net user} for networking is that @command{ping} will not work, because
25835 it uses the ICMP protocol. You'll have to use a different command to check for
25836 network connectivity, for example @command{guix download}.
25838 @subsection Connecting Through SSH
25842 To enable SSH inside a VM you need to add an SSH server like
25843 @code{openssh-service-type} to your VM (@pxref{Networking Services,
25844 @code{openssh-service-type}}). In addition you need to forward the SSH port,
25845 22 by default, to the host. You can do this with
25848 `guix system vm config.scm` -net user,hostfwd=tcp::10022-:22
25851 To connect to the VM you can run
25854 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
25857 The @command{-p} tells @command{ssh} the port you want to connect to.
25858 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
25859 every time you modify your @command{config.scm} file and the
25860 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
25861 connection to an unknown host every time you connect.
25863 @subsection Using @command{virt-viewer} with Spice
25865 As an alternative to the default @command{qemu} graphical client you can
25866 use the @command{remote-viewer} from the @command{virt-viewer} package. To
25867 connect pass the @command{-spice port=5930,disable-ticketing} flag to
25868 @command{qemu}. See previous section for further information on how to do this.
25870 Spice also allows you to do some nice stuff like share your clipboard with your
25871 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
25874 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
25875 -chardev spicevmc,name=vdagent,id=vdagent
25876 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
25877 name=com.redhat.spice.0
25880 You'll also need to add the @pxref{Miscellaneous Services, Spice service}.
25882 @node Defining Services
25883 @section Defining Services
25885 The previous sections show the available services and how one can combine
25886 them in an @code{operating-system} declaration. But how do we define
25887 them in the first place? And what is a service anyway?
25890 * Service Composition:: The model for composing services.
25891 * Service Types and Services:: Types and services.
25892 * Service Reference:: API reference.
25893 * Shepherd Services:: A particular type of service.
25896 @node Service Composition
25897 @subsection Service Composition
25901 Here we define a @dfn{service} as, broadly, something that extends the
25902 functionality of the operating system. Often a service is a process---a
25903 @dfn{daemon}---started when the system boots: a secure shell server, a
25904 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
25905 whose execution can be triggered by another daemon---e.g., an FTP server
25906 started by @command{inetd} or a D-Bus service activated by
25907 @command{dbus-daemon}. Occasionally, a service does not map to a
25908 daemon. For instance, the ``account'' service collects user accounts
25909 and makes sure they exist when the system runs; the ``udev'' service
25910 collects device management rules and makes them available to the eudev
25911 daemon; the @file{/etc} service populates the @file{/etc} directory
25914 @cindex service extensions
25915 Guix system services are connected by @dfn{extensions}. For instance, the
25916 secure shell service @emph{extends} the Shepherd---the
25917 initialization system, running as PID@tie{}1---by giving it the command
25918 lines to start and stop the secure shell daemon (@pxref{Networking
25919 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
25920 service by passing it its @file{.service} specification, and extends the
25921 udev service by passing it device management rules (@pxref{Desktop
25922 Services, @code{upower-service}}); the Guix daemon service extends the
25923 Shepherd by passing it the command lines to start and stop the daemon,
25924 and extends the account service by passing it a list of required build
25925 user accounts (@pxref{Base Services}).
25927 All in all, services and their ``extends'' relations form a directed
25928 acyclic graph (DAG). If we represent services as boxes and extensions
25929 as arrows, a typical system might provide something like this:
25931 @image{images/service-graph,,5in,Typical service extension graph.}
25933 @cindex system service
25934 At the bottom, we see the @dfn{system service}, which produces the
25935 directory containing everything to run and boot the system, as returned
25936 by the @command{guix system build} command. @xref{Service Reference},
25937 to learn about the other service types shown here.
25938 @xref{system-extension-graph, the @command{guix system extension-graph}
25939 command}, for information on how to generate this representation for a
25940 particular operating system definition.
25942 @cindex service types
25943 Technically, developers can define @dfn{service types} to express these
25944 relations. There can be any number of services of a given type on the
25945 system---for instance, a system running two instances of the GNU secure
25946 shell server (lsh) has two instances of @code{lsh-service-type}, with
25947 different parameters.
25949 The following section describes the programming interface for service
25950 types and services.
25952 @node Service Types and Services
25953 @subsection Service Types and Services
25955 A @dfn{service type} is a node in the DAG described above. Let us start
25956 with a simple example, the service type for the Guix build daemon
25957 (@pxref{Invoking guix-daemon}):
25960 (define guix-service-type
25964 (list (service-extension shepherd-root-service-type guix-shepherd-service)
25965 (service-extension account-service-type guix-accounts)
25966 (service-extension activation-service-type guix-activation)))
25967 (default-value (guix-configuration))))
25971 It defines three things:
25975 A name, whose sole purpose is to make inspection and debugging easier.
25978 A list of @dfn{service extensions}, where each extension designates the
25979 target service type and a procedure that, given the parameters of the
25980 service, returns a list of objects to extend the service of that type.
25982 Every service type has at least one service extension. The only
25983 exception is the @dfn{boot service type}, which is the ultimate service.
25986 Optionally, a default value for instances of this type.
25989 In this example, @code{guix-service-type} extends three services:
25992 @item shepherd-root-service-type
25993 The @code{guix-shepherd-service} procedure defines how the Shepherd
25994 service is extended. Namely, it returns a @code{<shepherd-service>}
25995 object that defines how @command{guix-daemon} is started and stopped
25996 (@pxref{Shepherd Services}).
25998 @item account-service-type
25999 This extension for this service is computed by @code{guix-accounts},
26000 which returns a list of @code{user-group} and @code{user-account}
26001 objects representing the build user accounts (@pxref{Invoking
26004 @item activation-service-type
26005 Here @code{guix-activation} is a procedure that returns a gexp, which is
26006 a code snippet to run at ``activation time''---e.g., when the service is
26010 A service of this type is instantiated like this:
26013 (service guix-service-type
26014 (guix-configuration
26016 (use-substitutes? #f)))
26019 The second argument to the @code{service} form is a value representing
26020 the parameters of this specific service instance.
26021 @xref{guix-configuration-type, @code{guix-configuration}}, for
26022 information about the @code{guix-configuration} data type. When the
26023 value is omitted, the default value specified by
26024 @code{guix-service-type} is used:
26027 (service guix-service-type)
26030 @code{guix-service-type} is quite simple because it extends other
26031 services but is not extensible itself.
26033 @c @subsubsubsection Extensible Service Types
26035 The service type for an @emph{extensible} service looks like this:
26038 (define udev-service-type
26039 (service-type (name 'udev)
26041 (list (service-extension shepherd-root-service-type
26042 udev-shepherd-service)))
26044 (compose concatenate) ;concatenate the list of rules
26045 (extend (lambda (config rules)
26047 (($ <udev-configuration> udev initial-rules)
26048 (udev-configuration
26049 (udev udev) ;the udev package to use
26050 (rules (append initial-rules rules)))))))))
26053 This is the service type for the
26054 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
26055 management daemon}. Compared to the previous example, in addition to an
26056 extension of @code{shepherd-root-service-type}, we see two new fields:
26060 This is the procedure to @dfn{compose} the list of extensions to
26061 services of this type.
26063 Services can extend the udev service by passing it lists of rules; we
26064 compose those extensions simply by concatenating them.
26067 This procedure defines how the value of the service is @dfn{extended} with
26068 the composition of the extensions.
26070 Udev extensions are composed into a list of rules, but the udev service
26071 value is itself a @code{<udev-configuration>} record. So here, we
26072 extend that record by appending the list of rules it contains to the
26073 list of contributed rules.
26076 This is a string giving an overview of the service type. The string can
26077 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
26078 @command{guix system search} command searches these strings and displays
26079 them (@pxref{Invoking guix system}).
26082 There can be only one instance of an extensible service type such as
26083 @code{udev-service-type}. If there were more, the
26084 @code{service-extension} specifications would be ambiguous.
26086 Still here? The next section provides a reference of the programming
26087 interface for services.
26089 @node Service Reference
26090 @subsection Service Reference
26092 We have seen an overview of service types (@pxref{Service Types and
26093 Services}). This section provides a reference on how to manipulate
26094 services and service types. This interface is provided by the
26095 @code{(gnu services)} module.
26097 @deffn {Scheme Procedure} service @var{type} [@var{value}]
26098 Return a new service of @var{type}, a @code{<service-type>} object (see
26099 below.) @var{value} can be any object; it represents the parameters of
26100 this particular service instance.
26102 When @var{value} is omitted, the default value specified by @var{type}
26103 is used; if @var{type} does not specify a default value, an error is
26106 For instance, this:
26109 (service openssh-service-type)
26113 is equivalent to this:
26116 (service openssh-service-type
26117 (openssh-configuration))
26120 In both cases the result is an instance of @code{openssh-service-type}
26121 with the default configuration.
26124 @deffn {Scheme Procedure} service? @var{obj}
26125 Return true if @var{obj} is a service.
26128 @deffn {Scheme Procedure} service-kind @var{service}
26129 Return the type of @var{service}---i.e., a @code{<service-type>} object.
26132 @deffn {Scheme Procedure} service-value @var{service}
26133 Return the value associated with @var{service}. It represents its
26137 Here is an example of how a service is created and manipulated:
26141 (service nginx-service-type
26142 (nginx-configuration
26144 (log-directory log-directory)
26145 (run-directory run-directory)
26146 (file config-file))))
26151 (eq? (service-kind s) nginx-service-type)
26155 The @code{modify-services} form provides a handy way to change the
26156 parameters of some of the services of a list such as
26157 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
26158 evaluates to a list of services. Of course, you could always use
26159 standard list combinators such as @code{map} and @code{fold} to do that
26160 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
26161 @code{modify-services} simply provides a more concise form for this
26164 @deffn {Scheme Syntax} modify-services @var{services} @
26165 (@var{type} @var{variable} => @var{body}) @dots{}
26167 Modify the services listed in @var{services} according to the given
26168 clauses. Each clause has the form:
26171 (@var{type} @var{variable} => @var{body})
26174 where @var{type} is a service type---e.g.,
26175 @code{guix-service-type}---and @var{variable} is an identifier that is
26176 bound within the @var{body} to the service parameters---e.g., a
26177 @code{guix-configuration} instance---of the original service of that
26180 The @var{body} should evaluate to the new service parameters, which will
26181 be used to configure the new service. This new service will replace the
26182 original in the resulting list. Because a service's service parameters
26183 are created using @code{define-record-type*}, you can write a succinct
26184 @var{body} that evaluates to the new service parameters by using the
26185 @code{inherit} feature that @code{define-record-type*} provides.
26187 @xref{Using the Configuration System}, for example usage.
26191 Next comes the programming interface for service types. This is
26192 something you want to know when writing new service definitions, but not
26193 necessarily when simply looking for ways to customize your
26194 @code{operating-system} declaration.
26196 @deftp {Data Type} service-type
26197 @cindex service type
26198 This is the representation of a @dfn{service type} (@pxref{Service Types
26203 This is a symbol, used only to simplify inspection and debugging.
26205 @item @code{extensions}
26206 A non-empty list of @code{<service-extension>} objects (see below).
26208 @item @code{compose} (default: @code{#f})
26209 If this is @code{#f}, then the service type denotes services that cannot
26210 be extended---i.e., services that do not receive ``values'' from other
26213 Otherwise, it must be a one-argument procedure. The procedure is called
26214 by @code{fold-services} and is passed a list of values collected from
26215 extensions. It may return any single value.
26217 @item @code{extend} (default: @code{#f})
26218 If this is @code{#f}, services of this type cannot be extended.
26220 Otherwise, it must be a two-argument procedure: @code{fold-services}
26221 calls it, passing it the initial value of the service as the first
26222 argument and the result of applying @code{compose} to the extension
26223 values as the second argument. It must return a value that is a valid
26224 parameter value for the service instance.
26227 @xref{Service Types and Services}, for examples.
26230 @deffn {Scheme Procedure} service-extension @var{target-type} @
26232 Return a new extension for services of type @var{target-type}.
26233 @var{compute} must be a one-argument procedure: @code{fold-services}
26234 calls it, passing it the value associated with the service that provides
26235 the extension; it must return a valid value for the target service.
26238 @deffn {Scheme Procedure} service-extension? @var{obj}
26239 Return true if @var{obj} is a service extension.
26242 Occasionally, you might want to simply extend an existing service. This
26243 involves creating a new service type and specifying the extension of
26244 interest, which can be verbose; the @code{simple-service} procedure
26245 provides a shorthand for this.
26247 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
26248 Return a service that extends @var{target} with @var{value}. This works
26249 by creating a singleton service type @var{name}, of which the returned
26250 service is an instance.
26252 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
26256 (simple-service 'my-mcron-job mcron-service-type
26257 #~(job '(next-hour (3)) "guix gc -F 2G"))
26261 At the core of the service abstraction lies the @code{fold-services}
26262 procedure, which is responsible for ``compiling'' a list of services
26263 down to a single directory that contains everything needed to boot and
26264 run the system---the directory shown by the @command{guix system build}
26265 command (@pxref{Invoking guix system}). In essence, it propagates
26266 service extensions down the service graph, updating each node parameters
26267 on the way, until it reaches the root node.
26269 @deffn {Scheme Procedure} fold-services @var{services} @
26270 [#:target-type @var{system-service-type}]
26271 Fold @var{services} by propagating their extensions down to the root of
26272 type @var{target-type}; return the root service adjusted accordingly.
26275 Lastly, the @code{(gnu services)} module also defines several essential
26276 service types, some of which are listed below.
26278 @defvr {Scheme Variable} system-service-type
26279 This is the root of the service graph. It produces the system directory
26280 as returned by the @command{guix system build} command.
26283 @defvr {Scheme Variable} boot-service-type
26284 The type of the ``boot service'', which produces the @dfn{boot script}.
26285 The boot script is what the initial RAM disk runs when booting.
26288 @defvr {Scheme Variable} etc-service-type
26289 The type of the @file{/etc} service. This service is used to create
26290 files under @file{/etc} and can be extended by
26291 passing it name/file tuples such as:
26294 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
26297 In this example, the effect would be to add an @file{/etc/issue} file
26298 pointing to the given file.
26301 @defvr {Scheme Variable} setuid-program-service-type
26302 Type for the ``setuid-program service''. This service collects lists of
26303 executable file names, passed as gexps, and adds them to the set of
26304 setuid-root programs on the system (@pxref{Setuid Programs}).
26307 @defvr {Scheme Variable} profile-service-type
26308 Type of the service that populates the @dfn{system profile}---i.e., the
26309 programs under @file{/run/current-system/profile}. Other services can
26310 extend it by passing it lists of packages to add to the system profile.
26314 @node Shepherd Services
26315 @subsection Shepherd Services
26317 @cindex shepherd services
26319 @cindex init system
26320 The @code{(gnu services shepherd)} module provides a way to define
26321 services managed by the GNU@tie{}Shepherd, which is the
26322 initialization system---the first process that is started when the
26323 system boots, also known as PID@tie{}1
26324 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
26326 Services in the Shepherd can depend on each other. For instance, the
26327 SSH daemon may need to be started after the syslog daemon has been
26328 started, which in turn can only happen once all the file systems have
26329 been mounted. The simple operating system defined earlier (@pxref{Using
26330 the Configuration System}) results in a service graph like this:
26332 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
26334 You can actually generate such a graph for any operating system
26335 definition using the @command{guix system shepherd-graph} command
26336 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
26338 The @code{%shepherd-root-service} is a service object representing
26339 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
26340 by passing it lists of @code{<shepherd-service>} objects.
26342 @deftp {Data Type} shepherd-service
26343 The data type representing a service managed by the Shepherd.
26346 @item @code{provision}
26347 This is a list of symbols denoting what the service provides.
26349 These are the names that may be passed to @command{herd start},
26350 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
26351 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
26352 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
26354 @item @code{requirement} (default: @code{'()})
26355 List of symbols denoting the Shepherd services this one depends on.
26357 @cindex one-shot services, for the Shepherd
26358 @item @code{one-shot?} (default: @code{#f})
26359 Whether this service is @dfn{one-shot}. One-shot services stop immediately
26360 after their @code{start} action has completed. @xref{Slots of services,,,
26361 shepherd, The GNU Shepherd Manual}, for more info.
26363 @item @code{respawn?} (default: @code{#t})
26364 Whether to restart the service when it stops, for instance when the
26365 underlying process dies.
26368 @itemx @code{stop} (default: @code{#~(const #f)})
26369 The @code{start} and @code{stop} fields refer to the Shepherd's
26370 facilities to start and stop processes (@pxref{Service De- and
26371 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
26372 G-expressions that get expanded in the Shepherd configuration file
26373 (@pxref{G-Expressions}).
26375 @item @code{actions} (default: @code{'()})
26376 @cindex actions, of Shepherd services
26377 This is a list of @code{shepherd-action} objects (see below) defining
26378 @dfn{actions} supported by the service, in addition to the standard
26379 @code{start} and @code{stop} actions. Actions listed here become available as
26380 @command{herd} sub-commands:
26383 herd @var{action} @var{service} [@var{arguments}@dots{}]
26386 @item @code{auto-start?} (default: @code{#t})
26387 Whether this service should be started automatically by the Shepherd. If it
26388 is @code{#f} the service has to be started manually with @code{herd start}.
26390 @item @code{documentation}
26391 A documentation string, as shown when running:
26394 herd doc @var{service-name}
26397 where @var{service-name} is one of the symbols in @code{provision}
26398 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
26400 @item @code{modules} (default: @code{%default-modules})
26401 This is the list of modules that must be in scope when @code{start} and
26402 @code{stop} are evaluated.
26407 @deftp {Data Type} shepherd-action
26408 This is the data type that defines additional actions implemented by a
26409 Shepherd service (see above).
26413 Symbol naming the action.
26415 @item documentation
26416 This is a documentation string for the action. It can be viewed by running:
26419 herd doc @var{service} action @var{action}
26423 This should be a gexp that evaluates to a procedure of at least one argument,
26424 which is the ``running value'' of the service (@pxref{Slots of services,,,
26425 shepherd, The GNU Shepherd Manual}).
26428 The following example defines an action called @code{say-hello} that kindly
26434 (documentation "Say hi!")
26435 (procedure #~(lambda (running . args)
26436 (format #t "Hello, friend! arguments: ~s\n"
26441 Assuming this action is added to the @code{example} service, then you can do:
26444 # herd say-hello example
26445 Hello, friend! arguments: ()
26446 # herd say-hello example a b c
26447 Hello, friend! arguments: ("a" "b" "c")
26450 This, as you can see, is a fairly sophisticated way to say hello.
26451 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
26455 @defvr {Scheme Variable} shepherd-root-service-type
26456 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
26458 This is the service type that extensions target when they want to create
26459 shepherd services (@pxref{Service Types and Services}, for an example).
26460 Each extension must pass a list of @code{<shepherd-service>}.
26463 @defvr {Scheme Variable} %shepherd-root-service
26464 This service represents PID@tie{}1.
26468 @node Documentation
26469 @chapter Documentation
26471 @cindex documentation, searching for
26472 @cindex searching for documentation
26473 @cindex Info, documentation format
26475 @cindex manual pages
26476 In most cases packages installed with Guix come with documentation.
26477 There are two main documentation formats: ``Info'', a browseable
26478 hypertext format used for GNU software, and ``manual pages'' (or ``man
26479 pages''), the linear documentation format traditionally found on Unix.
26480 Info manuals are accessed with the @command{info} command or with Emacs,
26481 and man pages are accessed using @command{man}.
26483 You can look for documentation of software installed on your system by
26484 keyword. For example, the following command searches for information
26485 about ``TLS'' in Info manuals:
26489 "(emacs)Network Security" -- STARTTLS
26490 "(emacs)Network Security" -- TLS
26491 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
26492 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
26497 The command below searches for the same keyword in man pages:
26501 SSL (7) - OpenSSL SSL/TLS library
26502 certtool (1) - GnuTLS certificate tool
26506 These searches are purely local to your computer so you have the
26507 guarantee that documentation you find corresponds to what you have
26508 actually installed, you can access it off-line, and your privacy is
26511 Once you have these results, you can view the relevant documentation by
26515 $ info "(gnutls)Core TLS API"
26525 Info manuals contain sections and indices as well as hyperlinks like
26526 those found in Web pages. The @command{info} reader (@pxref{Top, Info
26527 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
26528 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
26529 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
26530 Introduction}, for an introduction to Info navigation.
26532 @node Installing Debugging Files
26533 @chapter Installing Debugging Files
26535 @cindex debugging files
26536 Program binaries, as produced by the GCC compilers for instance, are
26537 typically written in the ELF format, with a section containing
26538 @dfn{debugging information}. Debugging information is what allows the
26539 debugger, GDB, to map binary code to source code; it is required to
26540 debug a compiled program in good conditions.
26542 The problem with debugging information is that is takes up a fair amount
26543 of disk space. For example, debugging information for the GNU C Library
26544 weighs in at more than 60 MiB. Thus, as a user, keeping all the
26545 debugging info of all the installed programs is usually not an option.
26546 Yet, space savings should not come at the cost of an impediment to
26547 debugging---especially in the GNU system, which should make it easier
26548 for users to exert their computing freedom (@pxref{GNU Distribution}).
26550 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
26551 mechanism that allows users to get the best of both worlds: debugging
26552 information can be stripped from the binaries and stored in separate
26553 files. GDB is then able to load debugging information from those files,
26554 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
26557 The GNU distribution takes advantage of this by storing debugging
26558 information in the @code{lib/debug} sub-directory of a separate package
26559 output unimaginatively called @code{debug} (@pxref{Packages with
26560 Multiple Outputs}). Users can choose to install the @code{debug} output
26561 of a package when they need it. For instance, the following command
26562 installs the debugging information for the GNU C Library and for GNU
26566 guix install glibc:debug guile:debug
26569 GDB must then be told to look for debug files in the user's profile, by
26570 setting the @code{debug-file-directory} variable (consider setting it
26571 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
26575 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
26578 From there on, GDB will pick up debugging information from the
26579 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
26581 In addition, you will most likely want GDB to be able to show the source
26582 code being debugged. To do that, you will have to unpack the source
26583 code of the package of interest (obtained with @code{guix build
26584 --source}, @pxref{Invoking guix build}), and to point GDB to that source
26585 directory using the @code{directory} command (@pxref{Source Path,
26586 @code{directory},, gdb, Debugging with GDB}).
26588 @c XXX: keep me up-to-date
26589 The @code{debug} output mechanism in Guix is implemented by the
26590 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
26591 opt-in---debugging information is available only for the packages
26592 with definitions explicitly declaring a @code{debug} output. This may be
26593 changed to opt-out in the future if our build farm servers can handle
26594 the load. To check whether a package has a @code{debug} output, use
26595 @command{guix package --list-available} (@pxref{Invoking guix package}).
26598 @node Security Updates
26599 @chapter Security Updates
26601 @cindex security updates
26602 @cindex security vulnerabilities
26603 Occasionally, important security vulnerabilities are discovered in software
26604 packages and must be patched. Guix developers try hard to keep track of
26605 known vulnerabilities and to apply fixes as soon as possible in the
26606 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
26607 containing only security updates.) The @command{guix lint} tool helps
26608 developers find out about vulnerable versions of software packages in the
26613 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
26614 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
26615 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
26619 @xref{Invoking guix lint}, for more information.
26621 Guix follows a functional
26622 package management discipline (@pxref{Introduction}), which implies
26623 that, when a package is changed, @emph{every package that depends on it}
26624 must be rebuilt. This can significantly slow down the deployment of
26625 fixes in core packages such as libc or Bash, since basically the whole
26626 distribution would need to be rebuilt. Using pre-built binaries helps
26627 (@pxref{Substitutes}), but deployment may still take more time than
26631 To address this, Guix implements @dfn{grafts}, a mechanism that allows
26632 for fast deployment of critical updates without the costs associated
26633 with a whole-distribution rebuild. The idea is to rebuild only the
26634 package that needs to be patched, and then to ``graft'' it onto packages
26635 explicitly installed by the user and that were previously referring to
26636 the original package. The cost of grafting is typically very low, and
26637 order of magnitudes lower than a full rebuild of the dependency chain.
26639 @cindex replacements of packages, for grafts
26640 For instance, suppose a security update needs to be applied to Bash.
26641 Guix developers will provide a package definition for the ``fixed''
26642 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
26643 Packages}). Then, the original package definition is augmented with a
26644 @code{replacement} field pointing to the package containing the bug fix:
26651 (replacement bash-fixed)))
26654 From there on, any package depending directly or indirectly on Bash---as
26655 reported by @command{guix gc --requisites} (@pxref{Invoking guix
26656 gc})---that is installed is automatically ``rewritten'' to refer to
26657 @code{bash-fixed} instead of @code{bash}. This grafting process takes
26658 time proportional to the size of the package, usually less than a
26659 minute for an ``average'' package on a recent machine. Grafting is
26660 recursive: when an indirect dependency requires grafting, then grafting
26661 ``propagates'' up to the package that the user is installing.
26663 Currently, the length of the name and version of the graft and that of
26664 the package it replaces (@code{bash-fixed} and @code{bash} in the example
26665 above) must be equal. This restriction mostly comes from the fact that
26666 grafting works by patching files, including binary files, directly.
26667 Other restrictions may apply: for instance, when adding a graft to a
26668 package providing a shared library, the original shared library and its
26669 replacement must have the same @code{SONAME} and be binary-compatible.
26671 The @option{--no-grafts} command-line option allows you to forcefully
26672 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
26676 guix build bash --no-grafts
26680 returns the store file name of the original Bash, whereas:
26687 returns the store file name of the ``fixed'', replacement Bash. This
26688 allows you to distinguish between the two variants of Bash.
26690 To verify which Bash your whole profile refers to, you can run
26691 (@pxref{Invoking guix gc}):
26694 guix gc -R `readlink -f ~/.guix-profile` | grep bash
26698 @dots{} and compare the store file names that you get with those above.
26699 Likewise for a complete Guix system generation:
26702 guix gc -R `guix system build my-config.scm` | grep bash
26705 Lastly, to check which Bash running processes are using, you can use the
26706 @command{lsof} command:
26709 lsof | grep /gnu/store/.*bash
26713 @node Bootstrapping
26714 @chapter Bootstrapping
26716 @c Adapted from the ELS 2013 paper.
26718 @cindex bootstrapping
26720 Bootstrapping in our context refers to how the distribution gets built
26721 ``from nothing''. Remember that the build environment of a derivation
26722 contains nothing but its declared inputs (@pxref{Introduction}). So
26723 there's an obvious chicken-and-egg problem: how does the first package
26724 get built? How does the first compiler get compiled? Note that this is
26725 a question of interest only to the curious hacker, not to the regular
26726 user, so you can shamelessly skip this section if you consider yourself
26727 a ``regular user''.
26729 @cindex bootstrap binaries
26730 The GNU system is primarily made of C code, with libc at its core. The
26731 GNU build system itself assumes the availability of a Bourne shell and
26732 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
26733 `grep'. Furthermore, build programs---programs that run
26734 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
26735 (@pxref{Derivations}). Consequently, to be able to build anything at
26736 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
26737 Binutils, libc, and the other packages mentioned above---the
26738 @dfn{bootstrap binaries}.
26740 These bootstrap binaries are ``taken for granted'', though we can also
26741 re-create them if needed (more on that later).
26743 @unnumberedsec Preparing to Use the Bootstrap Binaries
26745 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
26746 @c large image, it's hard to scroll. Oh well.
26747 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
26749 The figure above shows the very beginning of the dependency graph of the
26750 distribution, corresponding to the package definitions of the @code{(gnu
26751 packages bootstrap)} module. A similar figure can be generated with
26752 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
26755 guix graph -t derivation \
26756 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
26760 At this level of detail, things are
26761 slightly complex. First, Guile itself consists of an ELF executable,
26762 along with many source and compiled Scheme files that are dynamically
26763 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
26764 tarball shown in this graph. This tarball is part of Guix's ``source''
26765 distribution, and gets inserted into the store with @code{add-to-store}
26766 (@pxref{The Store}).
26768 But how do we write a derivation that unpacks this tarball and adds it
26769 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
26770 derivation---the first one that gets built---uses @code{bash} as its
26771 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
26772 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
26773 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
26774 the Guix source distribution, whose sole purpose is to allow the Guile
26775 tarball to be unpacked.
26777 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
26778 Guile that can be used to run subsequent build programs. Its first task
26779 is to download tarballs containing the other pre-built binaries---this
26780 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
26781 @code{ftp-client.scm} are used for this purpose. The
26782 @code{module-import.drv} derivations import those modules in a directory
26783 in the store, using the original layout. The
26784 @code{module-import-compiled.drv} derivations compile those modules, and
26785 write them in an output directory with the right layout. This
26786 corresponds to the @code{#:modules} argument of
26787 @code{build-expression->derivation} (@pxref{Derivations}).
26789 Finally, the various tarballs are unpacked by the
26790 derivations @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv},
26791 etc., at which point we have a working C tool chain.
26794 @unnumberedsec Building the Build Tools
26796 Bootstrapping is complete when we have a full tool chain that does not
26797 depend on the pre-built bootstrap tools discussed above. This
26798 no-dependency requirement is verified by checking whether the files of
26799 the final tool chain contain references to the @file{/gnu/store}
26800 directories of the bootstrap inputs. The process that leads to this
26801 ``final'' tool chain is described by the package definitions found in
26802 the @code{(gnu packages commencement)} module.
26804 The @command{guix graph} command allows us to ``zoom out'' compared to
26805 the graph above, by looking at the level of package objects instead of
26806 individual derivations---remember that a package may translate to
26807 several derivations, typically one derivation to download its source,
26808 one to build the Guile modules it needs, and one to actually build the
26809 package from source. The command:
26812 guix graph -t bag \
26813 -e '(@@@@ (gnu packages commencement)
26814 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
26818 produces the dependency graph leading to the ``final'' C
26819 library@footnote{You may notice the @code{glibc-intermediate} label,
26820 suggesting that it is not @emph{quite} final, but as a good
26821 approximation, we will consider it final.}, depicted below.
26823 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
26825 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
26826 The first tool that gets built with the bootstrap binaries is
26827 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
26828 for all the following packages. From there Findutils and Diffutils get
26831 Then come the first-stage Binutils and GCC, built as pseudo cross
26832 tools---i.e., with @code{--target} equal to @code{--host}. They are
26833 used to build libc. Thanks to this cross-build trick, this libc is
26834 guaranteed not to hold any reference to the initial tool chain.
26836 From there the final Binutils and GCC (not shown above) are built.
26838 from the final Binutils, and links programs against the just-built libc.
26839 This tool chain is used to build the other packages used by Guix and by
26840 the GNU Build System: Guile, Bash, Coreutils, etc.
26842 And voilà! At this point we have the complete set of build tools that
26843 the GNU Build System expects. These are in the @code{%final-inputs}
26844 variable of the @code{(gnu packages commencement)} module, and are
26845 implicitly used by any package that uses @code{gnu-build-system}
26846 (@pxref{Build Systems, @code{gnu-build-system}}).
26849 @unnumberedsec Building the Bootstrap Binaries
26851 @cindex bootstrap binaries
26852 Because the final tool chain does not depend on the bootstrap binaries,
26853 those rarely need to be updated. Nevertheless, it is useful to have an
26854 automated way to produce them, should an update occur, and this is what
26855 the @code{(gnu packages make-bootstrap)} module provides.
26857 The following command builds the tarballs containing the bootstrap
26858 binaries (Guile, Binutils, GCC, libc, and a tarball containing a mixture
26859 of Coreutils and other basic command-line tools):
26862 guix build bootstrap-tarballs
26865 The generated tarballs are those that should be referred to in the
26866 @code{(gnu packages bootstrap)} module mentioned at the beginning of
26869 Still here? Then perhaps by now you've started to wonder: when do we
26870 reach a fixed point? That is an interesting question! The answer is
26871 unknown, but if you would like to investigate further (and have
26872 significant computational and storage resources to do so), then let us
26875 @unnumberedsec Reducing the Set of Bootstrap Binaries
26877 Our bootstrap binaries currently include GCC, Guile, etc. That's a lot
26878 of binary code! Why is that a problem? It's a problem because these
26879 big chunks of binary code are practically non-auditable, which makes it
26880 hard to establish what source code produced them. Every unauditable
26881 binary also leaves us vulnerable to compiler backdoors as described by
26882 Ken Thompson in the 1984 paper @emph{Reflections on Trusting Trust}.
26884 This is mitigated by the fact that our bootstrap binaries were generated
26885 from an earlier Guix revision. Nevertheless it lacks the level of
26886 transparency that we get in the rest of the package dependency graph,
26887 where Guix always gives us a source-to-binary mapping. Thus, our goal
26888 is to reduce the set of bootstrap binaries to the bare minimum.
26890 The @uref{http://bootstrappable.org, Bootstrappable.org web site} lists
26891 on-going projects to do that. One of these is about replacing the
26892 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
26893 of increasing complexity, which could be built from source starting from
26894 a simple and auditable assembler. Your help is welcome!
26898 @chapter Porting to a New Platform
26900 As discussed above, the GNU distribution is self-contained, and
26901 self-containment is achieved by relying on pre-built ``bootstrap
26902 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
26903 operating system kernel, CPU architecture, and application binary
26904 interface (ABI). Thus, to port the distribution to a platform that is
26905 not yet supported, one must build those bootstrap binaries, and update
26906 the @code{(gnu packages bootstrap)} module to use them on that platform.
26908 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
26909 When everything goes well, and assuming the GNU tool chain supports the
26910 target platform, this can be as simple as running a command like this
26914 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
26917 For this to work, the @code{glibc-dynamic-linker} procedure in
26918 @code{(gnu packages bootstrap)} must be augmented to return the right
26919 file name for libc's dynamic linker on that platform; likewise,
26920 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
26921 taught about the new platform.
26923 Once these are built, the @code{(gnu packages bootstrap)} module needs
26924 to be updated to refer to these binaries on the target platform. That
26925 is, the hashes and URLs of the bootstrap tarballs for the new platform
26926 must be added alongside those of the currently supported platforms. The
26927 bootstrap Guile tarball is treated specially: it is expected to be
26928 available locally, and @file{gnu/local.mk} has rules to download it for
26929 the supported architectures; a rule for the new platform must be added
26932 In practice, there may be some complications. First, it may be that the
26933 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
26934 above) is not recognized by all the GNU tools. Typically, glibc
26935 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
26936 configure flag (see @code{gcc.scm} for examples of how to handle this).
26937 Second, some of the required packages could fail to build for that
26938 platform. Lastly, the generated binaries could be broken for some
26941 @c *********************************************************************
26942 @include contributing.texi
26944 @c *********************************************************************
26945 @node Acknowledgments
26946 @chapter Acknowledgments
26948 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
26949 which was designed and
26950 implemented by Eelco Dolstra, with contributions from other people (see
26951 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
26952 management, and promoted unprecedented features, such as transactional
26953 package upgrades and rollbacks, per-user profiles, and referentially
26954 transparent build processes. Without this work, Guix would not exist.
26956 The Nix-based software distributions, Nixpkgs and NixOS, have also been
26957 an inspiration for Guix.
26959 GNU@tie{}Guix itself is a collective work with contributions from a
26960 number of people. See the @file{AUTHORS} file in Guix for more
26961 information on these fine people. The @file{THANKS} file lists people
26962 who have helped by reporting bugs, taking care of the infrastructure,
26963 providing artwork and themes, making suggestions, and more---thank you!
26966 @c *********************************************************************
26967 @node GNU Free Documentation License
26968 @appendix GNU Free Documentation License
26969 @cindex license, GNU Free Documentation License
26970 @include fdl-1.3.texi
26972 @c *********************************************************************
26973 @node Concept Index
26974 @unnumbered Concept Index
26977 @node Programming Index
26978 @unnumbered Programming Index
26979 @syncodeindex tp fn
26980 @syncodeindex vr fn
26985 @c Local Variables:
26986 @c ispell-local-dictionary: "american";