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 KEY-SERVER pool.sks-keyservers.net
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 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 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018 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 $ gpg --keyserver @value{KEY-SERVER} \
562 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
566 and rerun the @code{gpg --verify} command.
567 @c end authentication part
570 Now, you need to become the @code{root} user. Depending on your distribution,
571 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
575 # tar --warning=no-timestamp -xf \
576 /path/to/guix-binary-@value{VERSION}.@var{system}.tar.xz
577 # mv var/guix /var/ && mv gnu /
580 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
581 The latter contains a ready-to-use profile for @code{root} (see next
584 Do @emph{not} unpack the tarball on a working Guix system since that
585 would overwrite its own essential files.
587 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
588 not emit warnings about ``implausibly old time stamps'' (such
589 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
591 They stem from the fact that all the
592 files in the archive have their modification time set to zero (which
593 means January 1st, 1970.) This is done on purpose to make sure the
594 archive content is independent of its creation time, thus making it
598 Make the profile available under @file{~root/.config/guix/current}, which is
599 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
602 # mkdir -p ~root/.config/guix
603 # ln -sf /var/guix/profiles/per-user/root/current-guix \
604 ~root/.config/guix/current
607 Source @file{etc/profile} to augment @code{PATH} and other relevant
608 environment variables:
611 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
612 source $GUIX_PROFILE/etc/profile
616 Create the group and user accounts for build users as explained below
617 (@pxref{Build Environment Setup}).
620 Run the daemon, and set it to automatically start on boot.
622 If your host distro uses the systemd init system, this can be achieved
625 @c Versions of systemd that supported symlinked service files are not
626 @c yet widely deployed, so we should suggest that users copy the service
629 @c See this thread for more information:
630 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
633 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
635 # systemctl start guix-daemon && systemctl enable guix-daemon
638 If your host distro uses the Upstart init system:
641 # initctl reload-configuration
642 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
647 Otherwise, you can still start the daemon manually with:
650 # ~root/.config/guix/current/bin/guix-daemon \
651 --build-users-group=guixbuild
655 Make the @command{guix} command available to other users on the machine,
659 # mkdir -p /usr/local/bin
661 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
664 It is also a good idea to make the Info version of this manual available
668 # mkdir -p /usr/local/share/info
669 # cd /usr/local/share/info
670 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
674 That way, assuming @file{/usr/local/share/info} is in the search path,
675 running @command{info guix} will open this manual (@pxref{Other Info
676 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
680 @cindex substitutes, authorization thereof
681 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
682 (@pxref{Substitutes}), authorize them:
685 # guix archive --authorize < \
686 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
690 Each user may need to perform a few additional steps to make their Guix
691 environment ready for use, @pxref{Application Setup}.
694 Voilà, the installation is complete!
696 You can confirm that Guix is working by installing a sample package into
703 The binary installation tarball can be (re)produced and verified simply
704 by running the following command in the Guix source tree:
707 make guix-binary.@var{system}.tar.xz
711 ...@: which, in turn, runs:
714 guix pack -s @var{system} --localstatedir \
715 --profile-name=current-guix guix
718 @xref{Invoking guix pack}, for more info on this handy tool.
721 @section Requirements
723 This section lists requirements when building Guix from source. The
724 build procedure for Guix is the same as for other GNU software, and is
725 not covered here. Please see the files @file{README} and @file{INSTALL}
726 in the Guix source tree for additional details.
728 @cindex official website
729 GNU Guix is available for download from its website at
730 @url{https://www.gnu.org/software/guix/}.
732 GNU Guix depends on the following packages:
735 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 2.2.x;
736 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
739 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
740 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
741 Guile,, gnutls-guile, GnuTLS-Guile});
743 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
746 @c FIXME: Specify a version number once a release has been made.
747 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
749 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON};
750 @item @url{https://zlib.net, zlib};
751 @item @url{https://www.gnu.org/software/make/, GNU Make}.
754 The following dependencies are optional:
758 @c Note: We need at least 0.10.2 for 'channel-send-eof'.
759 Support for build offloading (@pxref{Daemon Offload Setup}) and
760 @command{guix copy} (@pxref{Invoking guix copy}) depends on
761 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
762 version 0.10.2 or later.
765 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
766 substitutes can be used and @command{guix publish} can compress substitutes
770 When @url{http://www.bzip.org, libbz2} is available,
771 @command{guix-daemon} can use it to compress build logs.
774 Unless @code{--disable-daemon} was passed to @command{configure}, the
775 following packages are also needed:
778 @item @url{https://gnupg.org/, GNU libgcrypt};
779 @item @url{https://sqlite.org, SQLite 3};
780 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
784 @cindex state directory
785 When configuring Guix on a system that already has a Guix installation,
786 be sure to specify the same state directory as the existing installation
787 using the @code{--localstatedir} option of the @command{configure}
788 script (@pxref{Directory Variables, @code{localstatedir},, standards,
789 GNU Coding Standards}). The @command{configure} script protects against
790 unintended misconfiguration of @var{localstatedir} so you do not
791 inadvertently corrupt your store (@pxref{The Store}).
793 @cindex Nix, compatibility
794 When a working installation of @url{https://nixos.org/nix/, the Nix package
795 manager} is available, you
796 can instead configure Guix with @code{--disable-daemon}. In that case,
797 Nix replaces the three dependencies above.
799 Guix is compatible with Nix, so it is possible to share the same store
800 between both. To do so, you must pass @command{configure} not only the
801 same @code{--with-store-dir} value, but also the same
802 @code{--localstatedir} value. The latter is essential because it
803 specifies where the database that stores metadata about the store is
804 located, among other things. The default values for Nix are
805 @code{--with-store-dir=/nix/store} and @code{--localstatedir=/nix/var}.
806 Note that @code{--disable-daemon} is not required if
807 your goal is to share the store with Nix.
809 @node Running the Test Suite
810 @section Running the Test Suite
813 After a successful @command{configure} and @code{make} run, it is a good
814 idea to run the test suite. It can help catch issues with the setup or
815 environment, or bugs in Guix itself---and really, reporting test
816 failures is a good way to help improve the software. To run the test
823 Test cases can run in parallel: you can use the @code{-j} option of
824 GNU@tie{}make to speed things up. The first run may take a few minutes
825 on a recent machine; subsequent runs will be faster because the store
826 that is created for test purposes will already have various things in
829 It is also possible to run a subset of the tests by defining the
830 @code{TESTS} makefile variable as in this example:
833 make check TESTS="tests/store.scm tests/cpio.scm"
836 By default, tests results are displayed at a file level. In order to
837 see the details of every individual test cases, it is possible to define
838 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
841 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
844 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
845 @file{test-suite.log} file. Please specify the Guix version being used
846 as well as version numbers of the dependencies (@pxref{Requirements}) in
849 Guix also comes with a whole-system test suite that tests complete
850 Guix System instances. It can only run on systems where
851 Guix is already installed, using:
858 or, again, by defining @code{TESTS} to select a subset of tests to run:
861 make check-system TESTS="basic mcron"
864 These system tests are defined in the @code{(gnu tests @dots{})}
865 modules. They work by running the operating systems under test with
866 lightweight instrumentation in a virtual machine (VM). They can be
867 computationally intensive or rather cheap, depending on whether
868 substitutes are available for their dependencies (@pxref{Substitutes}).
869 Some of them require a lot of storage space to hold VM images.
871 Again in case of test failures, please send @email{bug-guix@@gnu.org}
874 @node Setting Up the Daemon
875 @section Setting Up the Daemon
878 Operations such as building a package or running the garbage collector
879 are all performed by a specialized process, the @dfn{build daemon}, on
880 behalf of clients. Only the daemon may access the store and its
881 associated database. Thus, any operation that manipulates the store
882 goes through the daemon. For instance, command-line tools such as
883 @command{guix package} and @command{guix build} communicate with the
884 daemon (@i{via} remote procedure calls) to instruct it what to do.
886 The following sections explain how to prepare the build daemon's
887 environment. See also @ref{Substitutes}, for information on how to allow
888 the daemon to download pre-built binaries.
891 * Build Environment Setup:: Preparing the isolated build environment.
892 * Daemon Offload Setup:: Offloading builds to remote machines.
893 * SELinux Support:: Using an SELinux policy for the daemon.
896 @node Build Environment Setup
897 @subsection Build Environment Setup
899 @cindex build environment
900 In a standard multi-user setup, Guix and its daemon---the
901 @command{guix-daemon} program---are installed by the system
902 administrator; @file{/gnu/store} is owned by @code{root} and
903 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
904 Guix tools to build packages or otherwise access the store, and the
905 daemon will do it on their behalf, ensuring that the store is kept in a
906 consistent state, and allowing built packages to be shared among users.
909 When @command{guix-daemon} runs as @code{root}, you may not want package
910 build processes themselves to run as @code{root} too, for obvious
911 security reasons. To avoid that, a special pool of @dfn{build users}
912 should be created for use by build processes started by the daemon.
913 These build users need not have a shell and a home directory: they will
914 just be used when the daemon drops @code{root} privileges in build
915 processes. Having several such users allows the daemon to launch
916 distinct build processes under separate UIDs, which guarantees that they
917 do not interfere with each other---an essential feature since builds are
918 regarded as pure functions (@pxref{Introduction}).
920 On a GNU/Linux system, a build user pool may be created like this (using
921 Bash syntax and the @code{shadow} commands):
923 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
924 @c for why `-G' is needed.
926 # groupadd --system guixbuild
927 # for i in `seq -w 1 10`;
929 useradd -g guixbuild -G guixbuild \
930 -d /var/empty -s `which nologin` \
931 -c "Guix build user $i" --system \
937 The number of build users determines how many build jobs may run in
938 parallel, as specified by the @option{--max-jobs} option
939 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
940 @command{guix system vm} and related commands, you may need to add the
941 build users to the @code{kvm} group so they can access @file{/dev/kvm},
942 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
943 (@pxref{Invoking guix system}).
945 The @code{guix-daemon} program may then be run as @code{root} with the
946 following command@footnote{If your machine uses the systemd init system,
947 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
948 file in @file{/etc/systemd/system} will ensure that
949 @command{guix-daemon} is automatically started. Similarly, if your
950 machine uses the Upstart init system, drop the
951 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
952 file in @file{/etc/init}.}:
955 # guix-daemon --build-users-group=guixbuild
960 This way, the daemon starts build processes in a chroot, under one of
961 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
962 environment contains nothing but:
964 @c Keep this list in sync with libstore/build.cc! -----------------------
967 a minimal @code{/dev} directory, created mostly independently from the
968 host @code{/dev}@footnote{``Mostly'', because while the set of files
969 that appear in the chroot's @code{/dev} is fixed, most of these files
970 can only be created if the host has them.};
973 the @code{/proc} directory; it only shows the processes of the container
974 since a separate PID name space is used;
977 @file{/etc/passwd} with an entry for the current user and an entry for
981 @file{/etc/group} with an entry for the user's group;
984 @file{/etc/hosts} with an entry that maps @code{localhost} to
988 a writable @file{/tmp} directory.
991 You can influence the directory where the daemon stores build trees
992 @i{via} the @code{TMPDIR} environment variable. However, the build tree
993 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
994 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
995 This way, the value of @code{TMPDIR} does not leak inside build
996 environments, which avoids discrepancies in cases where build processes
997 capture the name of their build tree.
1000 The daemon also honors the @code{http_proxy} environment variable for
1001 HTTP downloads it performs, be it for fixed-output derivations
1002 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1004 If you are installing Guix as an unprivileged user, it is still possible
1005 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1006 However, build processes will not be isolated from one another, and not
1007 from the rest of the system. Thus, build processes may interfere with
1008 each other, and may access programs, libraries, and other files
1009 available on the system---making it much harder to view them as
1010 @emph{pure} functions.
1013 @node Daemon Offload Setup
1014 @subsection Using the Offload Facility
1018 When desired, the build daemon can @dfn{offload} derivation builds to
1019 other machines running Guix, using the @code{offload} @dfn{build
1020 hook}@footnote{This feature is available only when
1021 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1022 present.}. When that
1023 feature is enabled, a list of user-specified build machines is read from
1024 @file{/etc/guix/machines.scm}; every time a build is requested, for
1025 instance via @code{guix build}, the daemon attempts to offload it to one
1026 of the machines that satisfy the constraints of the derivation, in
1027 particular its system type---e.g., @file{x86_64-linux}. Missing
1028 prerequisites for the build are copied over SSH to the target machine,
1029 which then proceeds with the build; upon success the output(s) of the
1030 build are copied back to the initial machine.
1032 The @file{/etc/guix/machines.scm} file typically looks like this:
1035 (list (build-machine
1036 (name "eightysix.example.org")
1037 (system "x86_64-linux")
1038 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1040 (speed 2.)) ;incredibly fast!
1043 (name "meeps.example.org")
1044 (system "mips64el-linux")
1045 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1048 (string-append (getenv "HOME")
1049 "/.ssh/identity-for-guix"))))
1053 In the example above we specify a list of two build machines, one for
1054 the @code{x86_64} architecture and one for the @code{mips64el}
1057 In fact, this file is---not surprisingly!---a Scheme file that is
1058 evaluated when the @code{offload} hook is started. Its return value
1059 must be a list of @code{build-machine} objects. While this example
1060 shows a fixed list of build machines, one could imagine, say, using
1061 DNS-SD to return a list of potential build machines discovered in the
1062 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1063 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1066 @deftp {Data Type} build-machine
1067 This data type represents build machines to which the daemon may offload
1068 builds. The important fields are:
1073 The host name of the remote machine.
1076 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1079 The user account to use when connecting to the remote machine over SSH.
1080 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1081 allow non-interactive logins.
1084 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1085 This is used to authenticate the machine when we connect to it. It is a
1086 long string that looks like this:
1089 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1092 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1093 key can be found in a file such as
1094 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1096 If the machine is running the SSH daemon of GNU@tie{}lsh,
1097 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1098 similar file. It can be converted to the OpenSSH format using
1099 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1102 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1103 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1108 A number of optional fields may be specified:
1112 @item @code{port} (default: @code{22})
1113 Port number of SSH server on the machine.
1115 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1116 The SSH private key file to use when connecting to the machine, in
1117 OpenSSH format. This key must not be protected with a passphrase.
1119 Note that the default value is the private key @emph{of the root
1120 account}. Make sure it exists if you use the default.
1122 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1123 @itemx @code{compression-level} (default: @code{3})
1124 The SSH-level compression methods and compression level requested.
1126 Note that offloading relies on SSH compression to reduce bandwidth usage
1127 when transferring files to and from build machines.
1129 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1130 File name of the Unix-domain socket @command{guix-daemon} is listening
1133 @item @code{parallel-builds} (default: @code{1})
1134 The number of builds that may run in parallel on the machine.
1136 @item @code{speed} (default: @code{1.0})
1137 A ``relative speed factor''. The offload scheduler will tend to prefer
1138 machines with a higher speed factor.
1140 @item @code{features} (default: @code{'()})
1141 A list of strings denoting specific features supported by the machine.
1142 An example is @code{"kvm"} for machines that have the KVM Linux modules
1143 and corresponding hardware support. Derivations can request features by
1144 name, and they will be scheduled on matching build machines.
1149 The @command{guix} command must be in the search path on the build
1150 machines. You can check whether this is the case by running:
1153 ssh build-machine guix repl --version
1156 There is one last thing to do once @file{machines.scm} is in place. As
1157 explained above, when offloading, files are transferred back and forth
1158 between the machine stores. For this to work, you first need to
1159 generate a key pair on each machine to allow the daemon to export signed
1160 archives of files from the store (@pxref{Invoking guix archive}):
1163 # guix archive --generate-key
1167 Each build machine must authorize the key of the master machine so that
1168 it accepts store items it receives from the master:
1171 # guix archive --authorize < master-public-key.txt
1175 Likewise, the master machine must authorize the key of each build machine.
1177 All the fuss with keys is here to express pairwise mutual trust
1178 relations between the master and the build machines. Concretely, when
1179 the master receives files from a build machine (and @i{vice versa}), its
1180 build daemon can make sure they are genuine, have not been tampered
1181 with, and that they are signed by an authorized key.
1183 @cindex offload test
1184 To test whether your setup is operational, run this command on the
1191 This will attempt to connect to each of the build machines specified in
1192 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1193 available on each machine, attempt to export to the machine and import
1194 from it, and report any error in the process.
1196 If you want to test a different machine file, just specify it on the
1200 # guix offload test machines-qualif.scm
1203 Last, you can test the subset of the machines whose name matches a
1204 regular expression like this:
1207 # guix offload test machines.scm '\.gnu\.org$'
1210 @cindex offload status
1211 To display the current load of all build hosts, run this command on the
1215 # guix offload status
1219 @node SELinux Support
1220 @subsection SELinux Support
1222 @cindex SELinux, daemon policy
1223 @cindex mandatory access control, SELinux
1224 @cindex security, guix-daemon
1225 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1226 can be installed on a system where SELinux is enabled, in order to label
1227 Guix files and to specify the expected behavior of the daemon. Since
1228 Guix System does not provide an SELinux base policy, the daemon policy cannot
1229 be used on Guix System.
1231 @subsubsection Installing the SELinux policy
1232 @cindex SELinux, policy installation
1233 To install the policy run this command as root:
1236 semodule -i etc/guix-daemon.cil
1239 Then relabel the file system with @code{restorecon} or by a different
1240 mechanism provided by your system.
1242 Once the policy is installed, the file system has been relabeled, and
1243 the daemon has been restarted, it should be running in the
1244 @code{guix_daemon_t} context. You can confirm this with the following
1248 ps -Zax | grep guix-daemon
1251 Monitor the SELinux log files as you run a command like @code{guix build
1252 hello} to convince yourself that SELinux permits all necessary
1255 @subsubsection Limitations
1256 @cindex SELinux, limitations
1258 This policy is not perfect. Here is a list of limitations or quirks
1259 that should be considered when deploying the provided SELinux policy for
1264 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1265 operations involve contexts that have anything to do with
1266 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1267 but it would be preferrable to define socket rules for only this label.
1270 @code{guix gc} cannot access arbitrary links to profiles. By design,
1271 the file label of the destination of a symlink is independent of the
1272 file label of the link itself. Although all profiles under
1273 $localstatedir are labelled, the links to these profiles inherit the
1274 label of the directory they are in. For links in the user’s home
1275 directory this will be @code{user_home_t}. But for links from the root
1276 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1277 directory, etc, this won’t work. @code{guix gc} would be prevented from
1278 reading and following these links.
1281 The daemon’s feature to listen for TCP connections might no longer work.
1282 This might require extra rules, because SELinux treats network sockets
1283 differently from files.
1286 Currently all files with a name matching the regular expression
1287 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1288 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1289 that name in any profile would be permitted to run in the
1290 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1291 build a package that provides this executable and convince a user to
1292 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1293 At that point SELinux could not prevent it from accessing files that are
1294 allowed for processes in that domain.
1296 We could generate a much more restrictive policy at installation time,
1297 so that only the @emph{exact} file name of the currently installed
1298 @code{guix-daemon} executable would be labelled with
1299 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1300 The downside is that root would have to install or upgrade the policy at
1301 installation time whenever the Guix package that provides the
1302 effectively running @code{guix-daemon} executable is upgraded.
1305 @node Invoking guix-daemon
1306 @section Invoking @command{guix-daemon}
1308 The @command{guix-daemon} program implements all the functionality to
1309 access the store. This includes launching build processes, running the
1310 garbage collector, querying the availability of a build result, etc. It
1311 is normally run as @code{root} like this:
1314 # guix-daemon --build-users-group=guixbuild
1318 For details on how to set it up, @pxref{Setting Up the Daemon}.
1321 @cindex container, build environment
1322 @cindex build environment
1323 @cindex reproducible builds
1324 By default, @command{guix-daemon} launches build processes under
1325 different UIDs, taken from the build group specified with
1326 @code{--build-users-group}. In addition, each build process is run in a
1327 chroot environment that only contains the subset of the store that the
1328 build process depends on, as specified by its derivation
1329 (@pxref{Programming Interface, derivation}), plus a set of specific
1330 system directories. By default, the latter contains @file{/dev} and
1331 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1332 @dfn{container}: in addition to having its own file system tree, it has
1333 a separate mount name space, its own PID name space, network name space,
1334 etc. This helps achieve reproducible builds (@pxref{Features}).
1336 When the daemon performs a build on behalf of the user, it creates a
1337 build directory under @file{/tmp} or under the directory specified by
1338 its @code{TMPDIR} environment variable. This directory is shared with
1339 the container for the duration of the build, though within the container,
1340 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1342 The build directory is automatically deleted upon completion, unless the
1343 build failed and the client specified @option{--keep-failed}
1344 (@pxref{Invoking guix build, @option{--keep-failed}}).
1346 The daemon listens for connections and spawns one sub-process for each session
1347 started by a client (one of the @command{guix} sub-commands.) The
1348 @command{guix processes} command allows you to get an overview of the activity
1349 on your system by viewing each of the active sessions and clients.
1350 @xref{Invoking guix processes}, for more information.
1352 The following command-line options are supported:
1355 @item --build-users-group=@var{group}
1356 Take users from @var{group} to run build processes (@pxref{Setting Up
1357 the Daemon, build users}).
1359 @item --no-substitutes
1361 Do not use substitutes for build products. That is, always build things
1362 locally instead of allowing downloads of pre-built binaries
1363 (@pxref{Substitutes}).
1365 When the daemon runs with @code{--no-substitutes}, clients can still
1366 explicitly enable substitution @i{via} the @code{set-build-options}
1367 remote procedure call (@pxref{The Store}).
1369 @item --substitute-urls=@var{urls}
1370 @anchor{daemon-substitute-urls}
1371 Consider @var{urls} the default whitespace-separated list of substitute
1372 source URLs. When this option is omitted,
1373 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1375 This means that substitutes may be downloaded from @var{urls}, as long
1376 as they are signed by a trusted signature (@pxref{Substitutes}).
1379 @item --no-build-hook
1380 Do not use the @dfn{build hook}.
1382 The build hook is a helper program that the daemon can start and to
1383 which it submits build requests. This mechanism is used to offload
1384 builds to other machines (@pxref{Daemon Offload Setup}).
1386 @item --cache-failures
1387 Cache build failures. By default, only successful builds are cached.
1389 When this option is used, @command{guix gc --list-failures} can be used
1390 to query the set of store items marked as failed; @command{guix gc
1391 --clear-failures} removes store items from the set of cached failures.
1392 @xref{Invoking guix gc}.
1394 @item --cores=@var{n}
1396 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1399 The default value is @code{0}, but it may be overridden by clients, such
1400 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1403 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1404 in the build process, which can then use it to exploit internal
1405 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1407 @item --max-jobs=@var{n}
1409 Allow at most @var{n} build jobs in parallel. The default value is
1410 @code{1}. Setting it to @code{0} means that no builds will be performed
1411 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1412 Setup}), or simply fail.
1414 @item --max-silent-time=@var{seconds}
1415 When the build or substitution process remains silent for more than
1416 @var{seconds}, terminate it and report a build failure.
1418 The default value is @code{0}, which disables the timeout.
1420 The value specified here can be overridden by clients (@pxref{Common
1421 Build Options, @code{--max-silent-time}}).
1423 @item --timeout=@var{seconds}
1424 Likewise, when the build or substitution process lasts for more than
1425 @var{seconds}, terminate it and report a build failure.
1427 The default value is @code{0}, which disables the timeout.
1429 The value specified here can be overridden by clients (@pxref{Common
1430 Build Options, @code{--timeout}}).
1432 @item --rounds=@var{N}
1433 Build each derivation @var{n} times in a row, and raise an error if
1434 consecutive build results are not bit-for-bit identical. Note that this
1435 setting can be overridden by clients such as @command{guix build}
1436 (@pxref{Invoking guix build}).
1438 When used in conjunction with @option{--keep-failed}, the differing
1439 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1440 This makes it easy to look for differences between the two results.
1443 Produce debugging output.
1445 This is useful to debug daemon start-up issues, but then it may be
1446 overridden by clients, for example the @code{--verbosity} option of
1447 @command{guix build} (@pxref{Invoking guix build}).
1449 @item --chroot-directory=@var{dir}
1450 Add @var{dir} to the build chroot.
1452 Doing this may change the result of build processes---for instance if
1453 they use optional dependencies found in @var{dir} when it is available,
1454 and not otherwise. For that reason, it is not recommended to do so.
1455 Instead, make sure that each derivation declares all the inputs that it
1458 @item --disable-chroot
1459 Disable chroot builds.
1461 Using this option is not recommended since, again, it would allow build
1462 processes to gain access to undeclared dependencies. It is necessary,
1463 though, when @command{guix-daemon} is running under an unprivileged user
1466 @item --log-compression=@var{type}
1467 Compress build logs according to @var{type}, one of @code{gzip},
1468 @code{bzip2}, or @code{none}.
1470 Unless @code{--lose-logs} is used, all the build logs are kept in the
1471 @var{localstatedir}. To save space, the daemon automatically compresses
1472 them with bzip2 by default.
1474 @item --disable-deduplication
1475 @cindex deduplication
1476 Disable automatic file ``deduplication'' in the store.
1478 By default, files added to the store are automatically ``deduplicated'':
1479 if a newly added file is identical to another one found in the store,
1480 the daemon makes the new file a hard link to the other file. This can
1481 noticeably reduce disk usage, at the expense of slightly increased
1482 input/output load at the end of a build process. This option disables
1485 @item --gc-keep-outputs[=yes|no]
1486 Tell whether the garbage collector (GC) must keep outputs of live
1490 @cindex garbage collector roots
1491 When set to ``yes'', the GC will keep the outputs of any live derivation
1492 available in the store---the @code{.drv} files. The default is ``no'',
1493 meaning that derivation outputs are kept only if they are reachable from a GC
1494 root. @xref{Invoking guix gc}, for more on GC roots.
1496 @item --gc-keep-derivations[=yes|no]
1497 Tell whether the garbage collector (GC) must keep derivations
1498 corresponding to live outputs.
1500 When set to ``yes'', as is the case by default, the GC keeps
1501 derivations---i.e., @code{.drv} files---as long as at least one of their
1502 outputs is live. This allows users to keep track of the origins of
1503 items in their store. Setting it to ``no'' saves a bit of disk space.
1505 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1506 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1507 ``yes'' causes liveness to flow from derivations to outputs. When both are
1508 set to ``yes'', the effect is to keep all the build prerequisites (the
1509 sources, compiler, libraries, and other build-time tools) of live objects in
1510 the store, regardless of whether these prerequisites are reachable from a GC
1511 root. This is convenient for developers since it saves rebuilds or downloads.
1513 @item --impersonate-linux-2.6
1514 On Linux-based systems, impersonate Linux 2.6. This means that the
1515 kernel's @code{uname} system call will report 2.6 as the release number.
1517 This might be helpful to build programs that (usually wrongfully) depend
1518 on the kernel version number.
1521 Do not keep build logs. By default they are kept under
1522 @code{@var{localstatedir}/guix/log}.
1524 @item --system=@var{system}
1525 Assume @var{system} as the current system type. By default it is the
1526 architecture/kernel pair found at configure time, such as
1527 @code{x86_64-linux}.
1529 @item --listen=@var{endpoint}
1530 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1531 as the file name of a Unix-domain socket if it starts with
1532 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1533 host name or host name and port to listen to. Here are a few examples:
1536 @item --listen=/gnu/var/daemon
1537 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1538 creating it if needed.
1540 @item --listen=localhost
1541 @cindex daemon, remote access
1542 @cindex remote access to the daemon
1543 @cindex daemon, cluster setup
1544 @cindex clusters, daemon setup
1545 Listen for TCP connections on the network interface corresponding to
1546 @code{localhost}, on port 44146.
1548 @item --listen=128.0.0.42:1234
1549 Listen for TCP connections on the network interface corresponding to
1550 @code{128.0.0.42}, on port 1234.
1553 This option can be repeated multiple times, in which case
1554 @command{guix-daemon} accepts connections on all the specified
1555 endpoints. Users can tell client commands what endpoint to connect to
1556 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1557 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1560 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1561 @code{--listen=@var{host}} is suitable on local networks, such as
1562 clusters, where only trusted nodes may connect to the build daemon. In
1563 other cases where remote access to the daemon is needed, we recommend
1564 using Unix-domain sockets along with SSH.
1567 When @code{--listen} is omitted, @command{guix-daemon} listens for
1568 connections on the Unix-domain socket located at
1569 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1573 @node Application Setup
1574 @section Application Setup
1576 @cindex foreign distro
1577 When using Guix on top of GNU/Linux distribution other than Guix System---a
1578 so-called @dfn{foreign distro}---a few additional steps are needed to
1579 get everything in place. Here are some of them.
1583 @anchor{locales-and-locpath}
1584 @cindex locales, when not on Guix System
1586 @vindex GUIX_LOCPATH
1587 Packages installed @i{via} Guix will not use the locale data of the
1588 host system. Instead, you must first install one of the locale packages
1589 available with Guix and then define the @code{GUIX_LOCPATH} environment
1593 $ guix install glibc-locales
1594 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1597 Note that the @code{glibc-locales} package contains data for all the
1598 locales supported by the GNU@tie{}libc and weighs in at around
1599 110@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1600 limited to a few UTF-8 locales.
1602 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1603 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1604 Manual}). There are two important differences though:
1608 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1609 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1610 to make sure the programs of the foreign distro will not end up loading
1611 incompatible locale data.
1614 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1615 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1616 should your Guix profile contain a mixture of programs linked against
1617 different libc version, each libc version will only try to load locale
1618 data in the right format.
1621 This is important because the locale data format used by different libc
1622 versions may be incompatible.
1624 @subsection Name Service Switch
1626 @cindex name service switch, glibc
1627 @cindex NSS (name service switch), glibc
1628 @cindex nscd (name service caching daemon)
1629 @cindex name service caching daemon (nscd)
1630 When using Guix on a foreign distro, we @emph{strongly recommend} that
1631 the system run the GNU C library's @dfn{name service cache daemon},
1632 @command{nscd}, which should be listening on the
1633 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1634 installed with Guix may fail to look up host names or user accounts, or
1635 may even crash. The next paragraphs explain why.
1637 @cindex @file{nsswitch.conf}
1638 The GNU C library implements a @dfn{name service switch} (NSS), which is
1639 an extensible mechanism for ``name lookups'' in general: host name
1640 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1641 The GNU C Library Reference Manual}).
1643 @cindex Network information service (NIS)
1644 @cindex NIS (Network information service)
1645 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1646 lookup implementations: for example, the @code{nss-mdns} plugin allow
1647 resolution of @code{.local} host names, the @code{nis} plugin allows
1648 user account lookup using the Network information service (NIS), and so
1649 on. These extra ``lookup services'' are configured system-wide in
1650 @file{/etc/nsswitch.conf}, and all the programs running on the system
1651 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1654 When they perform a name lookup---for instance by calling the
1655 @code{getaddrinfo} function in C---applications first try to connect to
1656 the nscd; on success, nscd performs name lookups on their behalf. If
1657 the nscd is not running, then they perform the name lookup by
1658 themselves, by loading the name lookup services into their own address
1659 space and running it. These name lookup services---the
1660 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1661 the host system's C library, rather than from the C library the
1662 application is linked against (the C library coming from Guix).
1664 And this is where the problem is: if your application is linked against
1665 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1666 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1667 likely crash or have its name lookups fail unexpectedly.
1669 Running @command{nscd} on the system, among other advantages, eliminates
1670 this binary incompatibility problem because those @code{libnss_*.so}
1671 files are loaded in the @command{nscd} process, not in applications
1674 @subsection X11 Fonts
1677 The majority of graphical applications use Fontconfig to locate and
1678 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1679 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1680 by default. Thus, to allow graphical applications installed with Guix
1681 to display fonts, you have to install fonts with Guix as well.
1682 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1683 @code{font-gnu-freefont-ttf}.
1685 To display text written in Chinese languages, Japanese, or Korean in
1686 graphical applications, consider installing
1687 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1688 has multiple outputs, one per language family (@pxref{Packages with
1689 Multiple Outputs}). For instance, the following command installs fonts
1690 for Chinese languages:
1693 guix install font-adobe-source-han-sans:cn
1696 @cindex @code{xterm}
1697 Older programs such as @command{xterm} do not use Fontconfig and instead
1698 rely on server-side font rendering. Such programs require to specify a
1699 full name of a font using XLFD (X Logical Font Description), like this:
1702 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1705 To be able to use such full names for the TrueType fonts installed in
1706 your Guix profile, you need to extend the font path of the X server:
1708 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1709 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1711 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1714 @cindex @code{xlsfonts}
1715 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1716 to make sure your TrueType fonts are listed there.
1718 @cindex @code{fc-cache}
1720 After installing fonts you may have to refresh the font cache to use
1721 them in applications. The same applies when applications installed via
1722 Guix do not seem to find fonts. To force rebuilding of the font cache
1723 run @code{fc-cache -f}. The @code{fc-cache} command is provided by the
1724 @code{fontconfig} package.
1726 @subsection X.509 Certificates
1728 @cindex @code{nss-certs}
1729 The @code{nss-certs} package provides X.509 certificates, which allow
1730 programs to authenticate Web servers accessed over HTTPS.
1732 When using Guix on a foreign distro, you can install this package and
1733 define the relevant environment variables so that packages know where to
1734 look for certificates. @xref{X.509 Certificates}, for detailed
1737 @subsection Emacs Packages
1739 @cindex @code{emacs}
1740 When you install Emacs packages with Guix, the elisp files may be placed
1741 either in @file{$HOME/.guix-profile/share/emacs/site-lisp/} or in
1743 @file{$HOME/.guix-profile/share/emacs/site-lisp/guix.d/}. The latter
1744 directory exists because potentially there may exist thousands of Emacs
1745 packages and storing all their files in a single directory may not be
1746 reliable (because of name conflicts). So we think using a separate
1747 directory for each package is a good idea. It is very similar to how
1748 the Emacs package system organizes the file structure (@pxref{Package
1749 Files,,, emacs, The GNU Emacs Manual}).
1751 By default, Emacs (installed with Guix) ``knows'' where these packages
1752 are placed, so you do not need to perform any configuration. If, for
1753 some reason, you want to avoid auto-loading Emacs packages installed
1754 with Guix, you can do so by running Emacs with @code{--no-site-file}
1755 option (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1757 @subsection The GCC toolchain
1762 Guix offers individual compiler packages such as @code{gcc} but if you
1763 are in need of a complete toolchain for compiling and linking source
1764 code what you really want is the @code{gcc-toolchain} package. This
1765 package provides a complete GCC toolchain for C/C++ development,
1766 including GCC itself, the GNU C Library (headers and binaries, plus
1767 debugging symbols in the @code{debug} output), Binutils, and a linker
1770 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
1771 passed to the linker, add corresponding @code{-rpath} arguments, and
1772 invoke the actual linker with this new set of arguments. You can instruct the
1773 wrapper to refuse to link against libraries not in the store by setting the
1774 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
1778 @c *********************************************************************
1779 @node System Installation
1780 @chapter System Installation
1782 @cindex installing Guix System
1783 @cindex Guix System, installation
1784 This section explains how to install Guix System
1785 on a machine. Guix, as a package manager, can
1786 also be installed on top of a running GNU/Linux system,
1787 @pxref{Installation}.
1791 @c This paragraph is for people reading this from tty2 of the
1792 @c installation image.
1793 You are reading this documentation with an Info reader. For details on
1794 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1795 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1796 Info}. Hit @kbd{l} afterwards to come back here.
1798 Alternately, run @command{info info} in another tty to keep the manual
1804 * Limitations:: What you can expect.
1805 * Hardware Considerations:: Supported hardware.
1806 * USB Stick and DVD Installation:: Preparing the installation medium.
1807 * Preparing for Installation:: Networking, partitioning, etc.
1808 * Guided Graphical Installation:: Easy graphical installation.
1809 * Manual Installation:: Manual installation for wizards.
1810 * After System Installation:: When installation succeeded.
1811 * Installing Guix in a VM:: Guix System playground.
1812 * Building the Installation Image:: How this comes to be.
1816 @section Limitations
1818 We consider Guix System to be ready for a wide range of ``desktop'' and server
1819 use cases. The reliability guarantees it provides---transactional upgrades
1820 and rollbacks, reproducibility---make it a solid foundation.
1822 Nevertheless, before you proceed with the installation, be aware of the
1823 following noteworthy limitations applicable to version @value{VERSION}:
1827 Support for the Logical Volume Manager (LVM) is missing.
1830 More and more system services are provided (@pxref{Services}), but some
1834 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1835 as well as a number of X11 window managers. However, KDE is currently
1839 More than a disclaimer, this is an invitation to report issues (and success
1840 stories!), and to join us in improving it. @xref{Contributing}, for more
1844 @node Hardware Considerations
1845 @section Hardware Considerations
1847 @cindex hardware support on Guix System
1848 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1849 builds around the kernel Linux-libre, which means that only hardware for
1850 which free software drivers and firmware exist is supported. Nowadays,
1851 a wide range of off-the-shelf hardware is supported on
1852 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1853 Ethernet controllers. Unfortunately, there are still areas where
1854 hardware vendors deny users control over their own computing, and such
1855 hardware is not supported on Guix System.
1857 @cindex WiFi, hardware support
1858 One of the main areas where free drivers or firmware are lacking is WiFi
1859 devices. WiFi devices known to work include those using Atheros chips
1860 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1861 driver, and those using Broadcom/AirForce chips (BCM43xx with
1862 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1863 Linux-libre driver. Free firmware exists for both and is available
1864 out-of-the-box on Guix System, as part of @code{%base-firmware}
1865 (@pxref{operating-system Reference, @code{firmware}}).
1867 @cindex RYF, Respects Your Freedom
1868 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1869 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1870 certification program for hardware products that respect your freedom
1871 and your privacy and ensure that you have control over your device. We
1872 encourage you to check the list of RYF-certified devices.
1874 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1875 web site. It contains a catalog of hardware devices with information
1876 about their support in GNU/Linux.
1879 @node USB Stick and DVD Installation
1880 @section USB Stick and DVD Installation
1882 An ISO-9660 installation image that can be written to a USB stick or
1883 burnt to a DVD can be downloaded from
1884 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1885 where @var{system} is one of:
1889 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1892 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1895 @c start duplication of authentication part from ``Binary Installation''
1896 Make sure to download the associated @file{.sig} file and to verify the
1897 authenticity of the image against it, along these lines:
1900 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1901 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1904 If that command fails because you do not have the required public key,
1905 then run this command to import it:
1908 $ gpg --keyserver @value{KEY-SERVER} \
1909 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
1913 and rerun the @code{gpg --verify} command.
1916 This image contains the tools necessary for an installation.
1917 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1919 @unnumberedsubsec Copying to a USB Stick
1921 To copy the image to a USB stick, follow these steps:
1925 Decompress the image using the @command{xz} command:
1928 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1932 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1933 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1934 copy the image with:
1937 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1941 Access to @file{/dev/sdX} usually requires root privileges.
1944 @unnumberedsubsec Burning on a DVD
1946 To copy the image to a DVD, follow these steps:
1950 Decompress the image using the @command{xz} command:
1953 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1957 Insert a blank DVD into your machine, and determine
1958 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
1959 copy the image with:
1962 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
1965 Access to @file{/dev/srX} usually requires root privileges.
1968 @unnumberedsubsec Booting
1970 Once this is done, you should be able to reboot the system and boot from
1971 the USB stick or DVD. The latter usually requires you to get in the
1972 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
1974 @xref{Installing Guix in a VM}, if, instead, you would like to install
1975 Guix System in a virtual machine (VM).
1978 @node Preparing for Installation
1979 @section Preparing for Installation
1981 Once you have booted, you can use the guided graphical installer, which makes
1982 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
1983 if you are already familiar with GNU/Linux and if you want more control than
1984 what the graphical installer provides, you can choose the ``manual''
1985 installation process (@pxref{Manual Installation}).
1987 The graphical installer is available on TTY1. You can obtain root shells on
1988 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
1989 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
1990 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
1991 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
1992 which allows you to select text with the left mouse button and to paste it
1993 with the middle button.
1996 Installation requires access to the Internet so that any missing
1997 dependencies of your system configuration can be downloaded. See the
1998 ``Networking'' section below.
2001 @node Guided Graphical Installation
2002 @section Guided Graphical Installation
2004 The graphical installer is a text-based user interface. It will guide you,
2005 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2007 The first dialog boxes allow you to set up the system as you use it during the
2008 installation: you can choose the language, keyboard layout, and set up
2009 networking, which will be used during the installation. The image below shows
2010 the networking dialog.
2012 @image{images/installer-network,5in,, networking setup with the graphical installer}
2014 Later steps allow you to partition your hard disk, as shown in the image
2015 below, to choose whether or not to use encrypted file systems, to enter the
2016 host name and root password, and to create an additional account, among other
2019 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2021 Note that, at any time, the installer allows you to exit the current
2022 installation step and resume at a previous step, as show in the image below.
2024 @image{images/installer-resume,5in,, resuming the installation process}
2026 Once you're done, the installer produces an operating system configuration and
2027 displays it (@pxref{Using the Configuration System}). At that point you can
2028 hit ``OK'' and installation will proceed. On success, you can reboot into the
2029 new system and enjoy. @xref{After System Installation}, for what's next!
2032 @node Manual Installation
2033 @section Manual Installation
2035 This section describes how you would ``manually'' install GNU@tie{}Guix System
2036 on your machine. This option requires familiarity with GNU/Linux, with the
2037 shell, and with common administration tools. If you think this is not for
2038 you, consider using the guided graphical installer (@pxref{Guided Graphical
2041 The installation system provides root shells on TTYs 3 to 6; press
2042 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2043 many common tools needed to install the system. But it is also a full-blown
2044 Guix System, which means that you can install additional packages, should you
2045 need it, using @command{guix package} (@pxref{Invoking guix package}).
2048 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2049 * Proceeding with the Installation:: Installing.
2052 @node Keyboard Layout and Networking and Partitioning
2053 @subsection Keyboard Layout, Networking, and Partitioning
2055 Before you can install the system, you may want to adjust the keyboard layout,
2056 set up networking, and partition your target hard disk. This section will
2057 guide you through this.
2059 @subsubsection Keyboard Layout
2061 @cindex keyboard layout
2062 The installation image uses the US qwerty keyboard layout. If you want
2063 to change it, you can use the @command{loadkeys} command. For example,
2064 the following command selects the Dvorak keyboard layout:
2070 See the files under @file{/run/current-system/profile/share/keymaps} for
2071 a list of available keyboard layouts. Run @command{man loadkeys} for
2074 @subsubsection Networking
2076 Run the following command to see what your network interfaces are called:
2083 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2089 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2090 Wired interfaces have a name starting with @samp{e}; for example, the
2091 interface corresponding to the first on-board Ethernet controller is
2092 called @samp{eno1}. Wireless interfaces have a name starting with
2093 @samp{w}, like @samp{w1p2s0}.
2096 @item Wired connection
2097 To configure a wired network run the following command, substituting
2098 @var{interface} with the name of the wired interface you want to use.
2101 ifconfig @var{interface} up
2104 @item Wireless connection
2107 To configure wireless networking, you can create a configuration file
2108 for the @command{wpa_supplicant} configuration tool (its location is not
2109 important) using one of the available text editors such as
2113 nano wpa_supplicant.conf
2116 As an example, the following stanza can go to this file and will work
2117 for many wireless networks, provided you give the actual SSID and
2118 passphrase for the network you are connecting to:
2122 ssid="@var{my-ssid}"
2124 psk="the network's secret passphrase"
2128 Start the wireless service and run it in the background with the
2129 following command (substitute @var{interface} with the name of the
2130 network interface you want to use):
2133 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2136 Run @command{man wpa_supplicant} for more information.
2140 At this point, you need to acquire an IP address. On a network where IP
2141 addresses are automatically assigned @i{via} DHCP, you can run:
2144 dhclient -v @var{interface}
2147 Try to ping a server to see if networking is up and running:
2153 Setting up network access is almost always a requirement because the
2154 image does not contain all the software and tools that may be needed.
2156 @cindex installing over SSH
2157 If you want to, you can continue the installation remotely by starting
2161 herd start ssh-daemon
2164 Make sure to either set a password with @command{passwd}, or configure
2165 OpenSSH public key authentication before logging in.
2167 @subsubsection Disk Partitioning
2169 Unless this has already been done, the next step is to partition, and
2170 then format the target partition(s).
2172 The installation image includes several partitioning tools, including
2173 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2174 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2175 the partition layout you want:
2181 If your disk uses the GUID Partition Table (GPT) format and you plan to
2182 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2183 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2186 @cindex EFI, installation
2187 @cindex UEFI, installation
2188 @cindex ESP, EFI system partition
2189 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2190 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2191 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2194 parted /dev/sda set 1 esp on
2198 @vindex grub-bootloader
2199 @vindex grub-efi-bootloader
2200 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2201 @file{/sys/firmware/efi} exists in the installation image, then you should
2202 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2203 Otherwise you should use the BIOS-based GRUB, known as
2204 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2208 Once you are done partitioning the target hard disk drive, you have to
2209 create a file system on the relevant partition(s)@footnote{Currently
2210 Guix System only supports ext4 and btrfs file systems. In particular, code
2211 that reads file system UUIDs and labels only works for these file system
2212 types.}. For the ESP, if you have one and assuming it is
2213 @file{/dev/sda1}, run:
2216 mkfs.fat -F32 /dev/sda1
2219 Preferably, assign file systems a label so that you can easily and
2220 reliably refer to them in @code{file-system} declarations (@pxref{File
2221 Systems}). This is typically done using the @code{-L} option of
2222 @command{mkfs.ext4} and related commands. So, assuming the target root
2223 partition lives at @file{/dev/sda2}, a file system with the label
2224 @code{my-root} can be created with:
2227 mkfs.ext4 -L my-root /dev/sda2
2230 @cindex encrypted disk
2231 If you are instead planning to encrypt the root partition, you can use
2232 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2233 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2234 @code{man cryptsetup}} for more information.) Assuming you want to
2235 store the root partition on @file{/dev/sda2}, the command sequence would
2236 be along these lines:
2239 cryptsetup luksFormat /dev/sda2
2240 cryptsetup open --type luks /dev/sda2 my-partition
2241 mkfs.ext4 -L my-root /dev/mapper/my-partition
2244 Once that is done, mount the target file system under @file{/mnt}
2245 with a command like (again, assuming @code{my-root} is the label of the
2249 mount LABEL=my-root /mnt
2252 Also mount any other file systems you would like to use on the target
2253 system relative to this path. If you have opted for @file{/boot/efi} as an
2254 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2255 found by @code{guix system init} afterwards.
2257 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2258 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2259 sure to initialize them with @command{mkswap}. Assuming you have one
2260 swap partition on @file{/dev/sda3}, you would run:
2267 Alternatively, you may use a swap file. For example, assuming that in
2268 the new system you want to use the file @file{/swapfile} as a swap file,
2269 you would run@footnote{This example will work for many types of file
2270 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2271 btrfs), the required steps may be different. For details, see the
2272 manual pages for @command{mkswap} and @command{swapon}.}:
2275 # This is 10 GiB of swap space. Adjust "count" to change the size.
2276 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2277 # For security, make the file readable and writable only by root.
2278 chmod 600 /mnt/swapfile
2279 mkswap /mnt/swapfile
2280 swapon /mnt/swapfile
2283 Note that if you have encrypted the root partition and created a swap
2284 file in its file system as described above, then the encryption also
2285 protects the swap file, just like any other file in that file system.
2287 @node Proceeding with the Installation
2288 @subsection Proceeding with the Installation
2290 With the target partitions ready and the target root mounted on
2291 @file{/mnt}, we're ready to go. First, run:
2294 herd start cow-store /mnt
2297 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2298 during the installation phase are written to the target disk on @file{/mnt}
2299 rather than kept in memory. This is necessary because the first phase of
2300 the @command{guix system init} command (see below) entails downloads or
2301 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2303 Next, you have to edit a file and
2304 provide the declaration of the operating system to be installed. To
2305 that end, the installation system comes with three text editors. We
2306 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2307 supports syntax highlighting and parentheses matching; other editors
2308 include GNU Zile (an Emacs clone), and
2309 nvi (a clone of the original BSD @command{vi} editor).
2310 We strongly recommend storing that file on the target root file system, say,
2311 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2312 configuration file once you have rebooted into the newly-installed system.
2314 @xref{Using the Configuration System}, for an overview of the
2315 configuration file. The example configurations discussed in that
2316 section are available under @file{/etc/configuration} in the
2317 installation image. Thus, to get started with a system configuration
2318 providing a graphical display server (a ``desktop'' system), you can run
2319 something along these lines:
2323 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2324 # nano /mnt/etc/config.scm
2327 You should pay attention to what your configuration file contains, and
2332 Make sure the @code{bootloader-configuration} form refers to the target
2333 you want to install GRUB on. It should mention @code{grub-bootloader} if
2334 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2335 for newer UEFI systems. For legacy systems, the @code{target} field
2336 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2337 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2338 currently mounted and a @code{file-system} entry is specified in your
2342 Be sure that your file system labels match the value of their respective
2343 @code{device} fields in your @code{file-system} configuration, assuming
2344 your @code{file-system} configuration uses the @code{file-system-label}
2345 procedure in its @code{device} field.
2348 If there are encrypted or RAID partitions, make sure to add a
2349 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2352 Once you are done preparing the configuration file, the new system must
2353 be initialized (remember that the target root file system is mounted
2357 guix system init /mnt/etc/config.scm /mnt
2361 This copies all the necessary files and installs GRUB on
2362 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2363 more information, @pxref{Invoking guix system}. This command may trigger
2364 downloads or builds of missing packages, which can take some time.
2366 Once that command has completed---and hopefully succeeded!---you can run
2367 @command{reboot} and boot into the new system. The @code{root} password
2368 in the new system is initially empty; other users' passwords need to be
2369 initialized by running the @command{passwd} command as @code{root},
2370 unless your configuration specifies otherwise
2371 (@pxref{user-account-password, user account passwords}).
2372 @xref{After System Installation}, for what's next!
2375 @node After System Installation
2376 @section After System Installation
2378 Success, you've now booted into Guix System! From then on, you can update the
2379 system whenever you want by running, say:
2383 sudo guix system reconfigure /etc/config.scm
2387 This builds a new system generation with the latest packages and services
2388 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2389 your system includes the latest security updates (@pxref{Security Updates}).
2391 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2393 @cindex sudo vs. @command{guix pull}
2394 Note that @command{sudo guix} runs your user's @command{guix} command and
2395 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2396 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2399 Join us on @code{#guix} on the Freenode IRC network or on
2400 @email{guix-devel@@gnu.org} to share your experience!
2403 @node Installing Guix in a VM
2404 @section Installing Guix in a Virtual Machine
2406 @cindex virtual machine, Guix System installation
2407 @cindex virtual private server (VPS)
2408 @cindex VPS (virtual private server)
2409 If you'd like to install Guix System in a virtual machine (VM) or on a
2410 virtual private server (VPS) rather than on your beloved machine, this
2413 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2414 disk image, follow these steps:
2418 First, retrieve and decompress the Guix system installation image as
2419 described previously (@pxref{USB Stick and DVD Installation}).
2422 Create a disk image that will hold the installed system. To make a
2423 qcow2-formatted disk image, use the @command{qemu-img} command:
2426 qemu-img create -f qcow2 guixsd.img 50G
2429 The resulting file will be much smaller than 50 GB (typically less than
2430 1 MB), but it will grow as the virtualized storage device is filled up.
2433 Boot the USB installation image in an VM:
2436 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2437 -net user -net nic,model=virtio -boot menu=on \
2438 -drive file=guix-system-install-@value{VERSION}.@var{system}.iso \
2439 -drive file=guixsd.img
2442 The ordering of the drives matters. @code{-enable-kvm} is optional, but
2443 significantly improves performance, @pxref{Running Guix in a VM}.
2445 In the VM console, quickly press the @kbd{F12} key to enter the boot
2446 menu. Then press the @kbd{2} key and the @kbd{RET} key to validate your
2450 You're now root in the VM, proceed with the installation process.
2451 @xref{Preparing for Installation}, and follow the instructions.
2454 Once installation is complete, you can boot the system that's on your
2455 @file{guixsd.img} image. @xref{Running Guix in a VM}, for how to do
2458 @node Building the Installation Image
2459 @section Building the Installation Image
2461 @cindex installation image
2462 The installation image described above was built using the @command{guix
2463 system} command, specifically:
2466 guix system disk-image --file-system-type=iso9660 \
2467 gnu/system/install.scm
2470 Have a look at @file{gnu/system/install.scm} in the source tree,
2471 and see also @ref{Invoking guix system} for more information
2472 about the installation image.
2474 @section Building the Installation Image for ARM Boards
2476 Many ARM boards require a specific variant of the
2477 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2479 If you build a disk image and the bootloader is not available otherwise
2480 (on another boot drive etc), it's advisable to build an image that
2481 includes the bootloader, specifically:
2484 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2487 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2488 board, a list of possible boards will be printed.
2490 @c *********************************************************************
2491 @node Package Management
2492 @chapter Package Management
2495 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2496 remove software packages, without having to know about their build
2497 procedures or dependencies. Guix also goes beyond this obvious set of
2500 This chapter describes the main features of Guix, as well as the
2501 package management tools it provides. Along with the command-line
2502 interface described below (@pxref{Invoking guix package, @code{guix
2503 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2504 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2505 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2509 guix install emacs-guix
2513 * Features:: How Guix will make your life brighter.
2514 * Invoking guix package:: Package installation, removal, etc.
2515 * Substitutes:: Downloading pre-built binaries.
2516 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2517 * Invoking guix gc:: Running the garbage collector.
2518 * Invoking guix pull:: Fetching the latest Guix and distribution.
2519 * Channels:: Customizing the package collection.
2520 * Inferiors:: Interacting with another revision of Guix.
2521 * Invoking guix describe:: Display information about your Guix revision.
2522 * Invoking guix archive:: Exporting and importing store files.
2528 When using Guix, each package ends up in the @dfn{package store}, in its
2529 own directory---something that resembles
2530 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2532 Instead of referring to these directories, users have their own
2533 @dfn{profile}, which points to the packages that they actually want to
2534 use. These profiles are stored within each user's home directory, at
2535 @code{$HOME/.guix-profile}.
2537 For example, @code{alice} installs GCC 4.7.2. As a result,
2538 @file{/home/alice/.guix-profile/bin/gcc} points to
2539 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2540 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2541 simply continues to point to
2542 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2543 coexist on the same system without any interference.
2545 The @command{guix package} command is the central tool to manage
2546 packages (@pxref{Invoking guix package}). It operates on the per-user
2547 profiles, and can be used @emph{with normal user privileges}.
2549 @cindex transactions
2550 The command provides the obvious install, remove, and upgrade
2551 operations. Each invocation is actually a @emph{transaction}: either
2552 the specified operation succeeds, or nothing happens. Thus, if the
2553 @command{guix package} process is terminated during the transaction,
2554 or if a power outage occurs during the transaction, then the user's
2555 profile remains in its previous state, and remains usable.
2557 In addition, any package transaction may be @emph{rolled back}. So, if,
2558 for example, an upgrade installs a new version of a package that turns
2559 out to have a serious bug, users may roll back to the previous instance
2560 of their profile, which was known to work well. Similarly, the global
2561 system configuration on Guix is subject to
2562 transactional upgrades and roll-back
2563 (@pxref{Using the Configuration System}).
2565 All packages in the package store may be @emph{garbage-collected}.
2566 Guix can determine which packages are still referenced by user
2567 profiles, and remove those that are provably no longer referenced
2568 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2569 generations of their profile so that the packages they refer to can be
2572 @cindex reproducibility
2573 @cindex reproducible builds
2574 Guix takes a @dfn{purely functional} approach to package
2575 management, as described in the introduction (@pxref{Introduction}).
2576 Each @file{/gnu/store} package directory name contains a hash of all the
2577 inputs that were used to build that package---compiler, libraries, build
2578 scripts, etc. This direct correspondence allows users to make sure a
2579 given package installation matches the current state of their
2580 distribution. It also helps maximize @dfn{build reproducibility}:
2581 thanks to the isolated build environments that are used, a given build
2582 is likely to yield bit-identical files when performed on different
2583 machines (@pxref{Invoking guix-daemon, container}).
2586 This foundation allows Guix to support @dfn{transparent binary/source
2587 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2588 available from an external source---a @dfn{substitute}, Guix just
2589 downloads it and unpacks it;
2590 otherwise, it builds the package from source, locally
2591 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2592 reproducible, users do not have to trust servers that provide
2593 substitutes: they can force a local build and @emph{challenge} providers
2594 (@pxref{Invoking guix challenge}).
2596 Control over the build environment is a feature that is also useful for
2597 developers. The @command{guix environment} command allows developers of
2598 a package to quickly set up the right development environment for their
2599 package, without having to manually install the dependencies of the
2600 package into their profile (@pxref{Invoking guix environment}).
2602 @cindex replication, of software environments
2603 @cindex provenance tracking, of software artifacts
2604 All of Guix and its package definitions is version-controlled, and
2605 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2606 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2607 Guix instance on a different machine or at a later point in time, which in
2608 turn allows you to @emph{replicate complete software environments}, while
2609 retaining precise @dfn{provenance tracking} of the software.
2611 @node Invoking guix package
2612 @section Invoking @command{guix package}
2614 @cindex installing packages
2615 @cindex removing packages
2616 @cindex package installation
2617 @cindex package removal
2618 The @command{guix package} command is the tool that allows users to
2619 install, upgrade, and remove packages, as well as rolling back to
2620 previous configurations. It operates only on the user's own profile,
2621 and works with normal user privileges (@pxref{Features}). Its syntax
2625 guix package @var{options}
2628 @cindex transactions
2629 Primarily, @var{options} specifies the operations to be performed during
2630 the transaction. Upon completion, a new profile is created, but
2631 previous @dfn{generations} of the profile remain available, should the user
2634 For example, to remove @code{lua} and install @code{guile} and
2635 @code{guile-cairo} in a single transaction:
2638 guix package -r lua -i guile guile-cairo
2641 @cindex aliases, for @command{guix package}
2642 For your convenience, we also provide the following aliases:
2646 @command{guix search} is an alias for @command{guix package -s},
2648 @command{guix install} is an alias for @command{guix package -i},
2650 @command{guix remove} is an alias for @command{guix package -r},
2652 and @command{guix upgrade} is an alias for @command{guix package -u}.
2655 These aliases are less expressive than @command{guix package} and provide
2656 fewer options, so in some cases you'll probably want to use @command{guix
2659 @command{guix package} also supports a @dfn{declarative approach}
2660 whereby the user specifies the exact set of packages to be available and
2661 passes it @i{via} the @option{--manifest} option
2662 (@pxref{profile-manifest, @option{--manifest}}).
2665 For each user, a symlink to the user's default profile is automatically
2666 created in @file{$HOME/.guix-profile}. This symlink always points to the
2667 current generation of the user's default profile. Thus, users can add
2668 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2669 variable, and so on.
2670 @cindex search paths
2671 If you are not using Guix System, consider adding the
2672 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2673 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2674 shells get all the right environment variable definitions:
2677 GUIX_PROFILE="$HOME/.guix-profile" ; \
2678 source "$HOME/.guix-profile/etc/profile"
2681 In a multi-user setup, user profiles are stored in a place registered as
2682 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2683 to (@pxref{Invoking guix gc}). That directory is normally
2684 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2685 @var{localstatedir} is the value passed to @code{configure} as
2686 @code{--localstatedir}, and @var{user} is the user name. The
2687 @file{per-user} directory is created when @command{guix-daemon} is
2688 started, and the @var{user} sub-directory is created by @command{guix
2691 The @var{options} can be among the following:
2695 @item --install=@var{package} @dots{}
2696 @itemx -i @var{package} @dots{}
2697 Install the specified @var{package}s.
2699 Each @var{package} may specify either a simple package name, such as
2700 @code{guile}, or a package name followed by an at-sign and version number,
2701 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2702 case, the newest version prefixed by @code{1.8} is selected.)
2704 If no version number is specified, the
2705 newest available version will be selected. In addition, @var{package}
2706 may contain a colon, followed by the name of one of the outputs of the
2707 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2708 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2709 name (and optionally version) are searched for among the GNU
2710 distribution modules (@pxref{Package Modules}).
2712 @cindex propagated inputs
2713 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2714 that automatically get installed along with the required package
2715 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2716 @code{package} objects}, for information about propagated inputs in
2717 package definitions).
2719 @anchor{package-cmd-propagated-inputs}
2720 An example is the GNU MPC library: its C header files refer to those of
2721 the GNU MPFR library, which in turn refer to those of the GMP library.
2722 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2723 in the profile; removing MPC also removes MPFR and GMP---unless they had
2724 also been explicitly installed by the user.
2726 Besides, packages sometimes rely on the definition of environment
2727 variables for their search paths (see explanation of
2728 @code{--search-paths} below). Any missing or possibly incorrect
2729 environment variable definitions are reported here.
2731 @item --install-from-expression=@var{exp}
2733 Install the package @var{exp} evaluates to.
2735 @var{exp} must be a Scheme expression that evaluates to a
2736 @code{<package>} object. This option is notably useful to disambiguate
2737 between same-named variants of a package, with expressions such as
2738 @code{(@@ (gnu packages base) guile-final)}.
2740 Note that this option installs the first output of the specified
2741 package, which may be insufficient when needing a specific output of a
2742 multiple-output package.
2744 @item --install-from-file=@var{file}
2745 @itemx -f @var{file}
2746 Install the package that the code within @var{file} evaluates to.
2748 As an example, @var{file} might contain a definition like this
2749 (@pxref{Defining Packages}):
2752 @verbatiminclude package-hello.scm
2755 Developers may find it useful to include such a @file{guix.scm} file
2756 in the root of their project source tree that can be used to test
2757 development snapshots and create reproducible development environments
2758 (@pxref{Invoking guix environment}).
2760 @item --remove=@var{package} @dots{}
2761 @itemx -r @var{package} @dots{}
2762 Remove the specified @var{package}s.
2764 As for @code{--install}, each @var{package} may specify a version number
2765 and/or output name in addition to the package name. For instance,
2766 @code{-r glibc:debug} would remove the @code{debug} output of
2769 @item --upgrade[=@var{regexp} @dots{}]
2770 @itemx -u [@var{regexp} @dots{}]
2771 @cindex upgrading packages
2772 Upgrade all the installed packages. If one or more @var{regexp}s are
2773 specified, upgrade only installed packages whose name matches a
2774 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2776 Note that this upgrades package to the latest version of packages found
2777 in the distribution currently installed. To update your distribution,
2778 you should regularly run @command{guix pull} (@pxref{Invoking guix
2781 @item --do-not-upgrade[=@var{regexp} @dots{}]
2782 When used together with the @code{--upgrade} option, do @emph{not}
2783 upgrade any packages whose name matches a @var{regexp}. For example, to
2784 upgrade all packages in the current profile except those containing the
2785 substring ``emacs'':
2788 $ guix package --upgrade . --do-not-upgrade emacs
2791 @item @anchor{profile-manifest}--manifest=@var{file}
2792 @itemx -m @var{file}
2793 @cindex profile declaration
2794 @cindex profile manifest
2795 Create a new generation of the profile from the manifest object
2796 returned by the Scheme code in @var{file}.
2798 This allows you to @emph{declare} the profile's contents rather than
2799 constructing it through a sequence of @code{--install} and similar
2800 commands. The advantage is that @var{file} can be put under version
2801 control, copied to different machines to reproduce the same profile, and
2804 @c FIXME: Add reference to (guix profile) documentation when available.
2805 @var{file} must return a @dfn{manifest} object, which is roughly a list
2808 @findex packages->manifest
2810 (use-package-modules guile emacs)
2815 ;; Use a specific package output.
2816 (list guile-2.0 "debug")))
2819 @findex specifications->manifest
2820 In this example we have to know which modules define the @code{emacs}
2821 and @code{guile-2.0} variables to provide the right
2822 @code{use-package-modules} line, which can be cumbersome. We can
2823 instead provide regular package specifications and let
2824 @code{specifications->manifest} look up the corresponding package
2828 (specifications->manifest
2829 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2833 @cindex rolling back
2834 @cindex undoing transactions
2835 @cindex transactions, undoing
2836 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2837 the last transaction.
2839 When combined with options such as @code{--install}, roll back occurs
2840 before any other actions.
2842 When rolling back from the first generation that actually contains
2843 installed packages, the profile is made to point to the @dfn{zeroth
2844 generation}, which contains no files apart from its own metadata.
2846 After having rolled back, installing, removing, or upgrading packages
2847 overwrites previous future generations. Thus, the history of the
2848 generations in a profile is always linear.
2850 @item --switch-generation=@var{pattern}
2851 @itemx -S @var{pattern}
2853 Switch to a particular generation defined by @var{pattern}.
2855 @var{pattern} may be either a generation number or a number prefixed
2856 with ``+'' or ``-''. The latter means: move forward/backward by a
2857 specified number of generations. For example, if you want to return to
2858 the latest generation after @code{--roll-back}, use
2859 @code{--switch-generation=+1}.
2861 The difference between @code{--roll-back} and
2862 @code{--switch-generation=-1} is that @code{--switch-generation} will
2863 not make a zeroth generation, so if a specified generation does not
2864 exist, the current generation will not be changed.
2866 @item --search-paths[=@var{kind}]
2867 @cindex search paths
2868 Report environment variable definitions, in Bash syntax, that may be
2869 needed in order to use the set of installed packages. These environment
2870 variables are used to specify @dfn{search paths} for files used by some
2871 of the installed packages.
2873 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2874 environment variables to be defined so it can look for headers and
2875 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2876 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2877 library are installed in the profile, then @code{--search-paths} will
2878 suggest setting these variables to @code{@var{profile}/include} and
2879 @code{@var{profile}/lib}, respectively.
2881 The typical use case is to define these environment variables in the
2885 $ eval `guix package --search-paths`
2888 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2889 meaning that the returned environment variable definitions will either
2890 be exact settings, or prefixes or suffixes of the current value of these
2891 variables. When omitted, @var{kind} defaults to @code{exact}.
2893 This option can also be used to compute the @emph{combined} search paths
2894 of several profiles. Consider this example:
2897 $ guix package -p foo -i guile
2898 $ guix package -p bar -i guile-json
2899 $ guix package -p foo -p bar --search-paths
2902 The last command above reports about the @code{GUILE_LOAD_PATH}
2903 variable, even though, taken individually, neither @file{foo} nor
2904 @file{bar} would lead to that recommendation.
2907 @item --profile=@var{profile}
2908 @itemx -p @var{profile}
2909 Use @var{profile} instead of the user's default profile.
2911 @cindex collisions, in a profile
2912 @cindex colliding packages in profiles
2913 @cindex profile collisions
2914 @item --allow-collisions
2915 Allow colliding packages in the new profile. Use at your own risk!
2917 By default, @command{guix package} reports as an error @dfn{collisions}
2918 in the profile. Collisions happen when two or more different versions
2919 or variants of a given package end up in the profile.
2922 Use the bootstrap Guile to build the profile. This option is only
2923 useful to distribution developers.
2927 In addition to these actions, @command{guix package} supports the
2928 following options to query the current state of a profile, or the
2929 availability of packages:
2933 @item --search=@var{regexp}
2934 @itemx -s @var{regexp}
2935 @cindex searching for packages
2936 List the available packages whose name, synopsis, or description matches
2937 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
2938 Print all the metadata of matching packages in
2939 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
2940 GNU recutils manual}).
2942 This allows specific fields to be extracted using the @command{recsel}
2943 command, for instance:
2946 $ guix package -s malloc | recsel -p name,version,relevance
2960 Similarly, to show the name of all the packages available under the
2961 terms of the GNU@tie{}LGPL version 3:
2964 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
2971 It is also possible to refine search results using several @code{-s} flags to
2972 @command{guix package}, or several arguments to @command{guix search}. For
2973 example, the following command returns a list of board games (this time using
2974 the @command{guix search} alias):
2977 $ guix search '\<board\>' game | recsel -p name
2982 If we were to omit @code{-s game}, we would also get software packages
2983 that deal with printed circuit boards; removing the angle brackets
2984 around @code{board} would further add packages that have to do with
2987 And now for a more elaborate example. The following command searches
2988 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
2989 libraries, and prints the name and synopsis of the matching packages:
2992 $ guix search crypto library | \
2993 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
2997 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
2998 information on @dfn{selection expressions} for @code{recsel -e}.
3000 @item --show=@var{package}
3001 Show details about @var{package}, taken from the list of available packages, in
3002 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3006 $ guix package --show=python | recsel -p name,version
3014 You may also specify the full name of a package to only get details about a
3015 specific version of it:
3017 $ guix package --show=python@@3.4 | recsel -p name,version
3024 @item --list-installed[=@var{regexp}]
3025 @itemx -I [@var{regexp}]
3026 List the currently installed packages in the specified profile, with the
3027 most recently installed packages shown last. When @var{regexp} is
3028 specified, list only installed packages whose name matches @var{regexp}.
3030 For each installed package, print the following items, separated by
3031 tabs: the package name, its version string, the part of the package that
3032 is installed (for instance, @code{out} for the default output,
3033 @code{include} for its headers, etc.), and the path of this package in
3036 @item --list-available[=@var{regexp}]
3037 @itemx -A [@var{regexp}]
3038 List packages currently available in the distribution for this system
3039 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3040 installed packages whose name matches @var{regexp}.
3042 For each package, print the following items separated by tabs: its name,
3043 its version string, the parts of the package (@pxref{Packages with
3044 Multiple Outputs}), and the source location of its definition.
3046 @item --list-generations[=@var{pattern}]
3047 @itemx -l [@var{pattern}]
3049 Return a list of generations along with their creation dates; for each
3050 generation, show the installed packages, with the most recently
3051 installed packages shown last. Note that the zeroth generation is never
3054 For each installed package, print the following items, separated by
3055 tabs: the name of a package, its version string, the part of the package
3056 that is installed (@pxref{Packages with Multiple Outputs}), and the
3057 location of this package in the store.
3059 When @var{pattern} is used, the command returns only matching
3060 generations. Valid patterns include:
3063 @item @emph{Integers and comma-separated integers}. Both patterns denote
3064 generation numbers. For instance, @code{--list-generations=1} returns
3067 And @code{--list-generations=1,8,2} outputs three generations in the
3068 specified order. Neither spaces nor trailing commas are allowed.
3070 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3071 specified generations and everything in between. Note that the start of
3072 a range must be smaller than its end.
3074 It is also possible to omit the endpoint. For example,
3075 @code{--list-generations=2..}, returns all generations starting from the
3078 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3079 or months by passing an integer along with the first letter of the
3080 duration. For example, @code{--list-generations=20d} lists generations
3081 that are up to 20 days old.
3084 @item --delete-generations[=@var{pattern}]
3085 @itemx -d [@var{pattern}]
3086 When @var{pattern} is omitted, delete all generations except the current
3089 This command accepts the same patterns as @option{--list-generations}.
3090 When @var{pattern} is specified, delete the matching generations. When
3091 @var{pattern} specifies a duration, generations @emph{older} than the
3092 specified duration match. For instance, @code{--delete-generations=1m}
3093 deletes generations that are more than one month old.
3095 If the current generation matches, it is @emph{not} deleted. Also, the
3096 zeroth generation is never deleted.
3098 Note that deleting generations prevents rolling back to them.
3099 Consequently, this command must be used with care.
3103 Finally, since @command{guix package} may actually start build
3104 processes, it supports all the common build options (@pxref{Common Build
3105 Options}). It also supports package transformation options, such as
3106 @option{--with-source} (@pxref{Package Transformation Options}).
3107 However, note that package transformations are lost when upgrading; to
3108 preserve transformations across upgrades, you should define your own
3109 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3110 (@pxref{Defining Packages}).
3113 @section Substitutes
3116 @cindex pre-built binaries
3117 Guix supports transparent source/binary deployment, which means that it
3118 can either build things locally, or download pre-built items from a
3119 server, or both. We call these pre-built items @dfn{substitutes}---they
3120 are substitutes for local build results. In many cases, downloading a
3121 substitute is much faster than building things locally.
3123 Substitutes can be anything resulting from a derivation build
3124 (@pxref{Derivations}). Of course, in the common case, they are
3125 pre-built package binaries, but source tarballs, for instance, which
3126 also result from derivation builds, can be available as substitutes.
3129 * Official Substitute Server:: One particular source of substitutes.
3130 * Substitute Server Authorization:: How to enable or disable substitutes.
3131 * Substitute Authentication:: How Guix verifies substitutes.
3132 * Proxy Settings:: How to get substitutes via proxy.
3133 * Substitution Failure:: What happens when substitution fails.
3134 * On Trusting Binaries:: How can you trust that binary blob?
3137 @node Official Substitute Server
3138 @subsection Official Substitute Server
3141 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3142 that builds packages from Guix continuously for some
3143 architectures, and makes them available as substitutes. This is the
3144 default source of substitutes; it can be overridden by passing the
3145 @option{--substitute-urls} option either to @command{guix-daemon}
3146 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3147 or to client tools such as @command{guix package}
3148 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3151 Substitute URLs can be either HTTP or HTTPS.
3152 HTTPS is recommended because communications are encrypted; conversely,
3153 using HTTP makes all communications visible to an eavesdropper, who
3154 could use the information gathered to determine, for instance, whether
3155 your system has unpatched security vulnerabilities.
3157 Substitutes from the official build farm are enabled by default when
3158 using Guix System (@pxref{GNU Distribution}). However,
3159 they are disabled by default when using Guix on a foreign distribution,
3160 unless you have explicitly enabled them via one of the recommended
3161 installation steps (@pxref{Installation}). The following paragraphs
3162 describe how to enable or disable substitutes for the official build
3163 farm; the same procedure can also be used to enable substitutes for any
3164 other substitute server.
3166 @node Substitute Server Authorization
3167 @subsection Substitute Server Authorization
3170 @cindex substitutes, authorization thereof
3171 @cindex access control list (ACL), for substitutes
3172 @cindex ACL (access control list), for substitutes
3173 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3175 must add its public key to the access control list (ACL) of archive
3176 imports, using the @command{guix archive} command (@pxref{Invoking guix
3177 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3178 be compromised and to serve genuine substitutes.
3180 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3181 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3182 the installation prefix of Guix. If you installed Guix from source,
3183 make sure you checked the GPG signature of
3184 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3185 Then, you can run something like this:
3188 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3191 Once this is in place, the output of a command like @code{guix build}
3192 should change from something like:
3195 $ guix build emacs --dry-run
3196 The following derivations would be built:
3197 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3198 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3199 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3200 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3208 $ guix build emacs --dry-run
3209 112.3 MB would be downloaded:
3210 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3211 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3212 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3213 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3218 This indicates that substitutes from @code{@value{SUBSTITUTE-SERVER}} are usable and
3219 will be downloaded, when possible, for future builds.
3221 @cindex substitutes, how to disable
3222 The substitute mechanism can be disabled globally by running
3223 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3224 guix-daemon}). It can also be disabled temporarily by passing the
3225 @code{--no-substitutes} option to @command{guix package}, @command{guix
3226 build}, and other command-line tools.
3228 @node Substitute Authentication
3229 @subsection Substitute Authentication
3231 @cindex digital signatures
3232 Guix detects and raises an error when attempting to use a substitute
3233 that has been tampered with. Likewise, it ignores substitutes that are
3234 not signed, or that are not signed by one of the keys listed in the ACL.
3236 There is one exception though: if an unauthorized server provides
3237 substitutes that are @emph{bit-for-bit identical} to those provided by
3238 an authorized server, then the unauthorized server becomes eligible for
3239 downloads. For example, assume we have chosen two substitute servers
3243 --substitute-urls="https://a.example.org https://b.example.org"
3247 @cindex reproducible builds
3248 If the ACL contains only the key for @code{b.example.org}, and if
3249 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3250 then Guix will download substitutes from @code{a.example.org} because it
3251 comes first in the list and can be considered a mirror of
3252 @code{b.example.org}. In practice, independent build machines usually
3253 produce the same binaries, thanks to bit-reproducible builds (see
3256 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3257 (in other words, the server is not authenticated), contrary to what
3258 HTTPS clients such as Web browsers usually do. This is because Guix
3259 authenticates substitute information itself, as explained above, which
3260 is what we care about (whereas X.509 certificates are about
3261 authenticating bindings between domain names and public keys.)
3263 @node Proxy Settings
3264 @subsection Proxy Settings
3267 Substitutes are downloaded over HTTP or HTTPS.
3268 The @code{http_proxy} environment
3269 variable can be set in the environment of @command{guix-daemon} and is
3270 honored for downloads of substitutes. Note that the value of
3271 @code{http_proxy} in the environment where @command{guix build},
3272 @command{guix package}, and other client commands are run has
3273 @emph{absolutely no effect}.
3275 @node Substitution Failure
3276 @subsection Substitution Failure
3278 Even when a substitute for a derivation is available, sometimes the
3279 substitution attempt will fail. This can happen for a variety of
3280 reasons: the substitute server might be offline, the substitute may
3281 recently have been deleted, the connection might have been interrupted,
3284 When substitutes are enabled and a substitute for a derivation is
3285 available, but the substitution attempt fails, Guix will attempt to
3286 build the derivation locally depending on whether or not
3287 @code{--fallback} was given (@pxref{fallback-option,, common build
3288 option @code{--fallback}}). Specifically, if @code{--fallback} was
3289 omitted, then no local build will be performed, and the derivation is
3290 considered to have failed. However, if @code{--fallback} was given,
3291 then Guix will attempt to build the derivation locally, and the success
3292 or failure of the derivation depends on the success or failure of the
3293 local build. Note that when substitutes are disabled or no substitute
3294 is available for the derivation in question, a local build will
3295 @emph{always} be performed, regardless of whether or not
3296 @code{--fallback} was given.
3298 To get an idea of how many substitutes are available right now, you can
3299 try running the @command{guix weather} command (@pxref{Invoking guix
3300 weather}). This command provides statistics on the substitutes provided
3303 @node On Trusting Binaries
3304 @subsection On Trusting Binaries
3306 @cindex trust, of pre-built binaries
3307 Today, each individual's control over their own computing is at the
3308 mercy of institutions, corporations, and groups with enough power and
3309 determination to subvert the computing infrastructure and exploit its
3310 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3311 convenient, we encourage users to also build on their own, or even run
3312 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3313 interesting target. One way to help is by publishing the software you
3314 build using @command{guix publish} so that others have one more choice
3315 of server to download substitutes from (@pxref{Invoking guix publish}).
3317 Guix has the foundations to maximize build reproducibility
3318 (@pxref{Features}). In most cases, independent builds of a given
3319 package or derivation should yield bit-identical results. Thus, through
3320 a diverse set of independent package builds, we can strengthen the
3321 integrity of our systems. The @command{guix challenge} command aims to
3322 help users assess substitute servers, and to assist developers in
3323 finding out about non-deterministic package builds (@pxref{Invoking guix
3324 challenge}). Similarly, the @option{--check} option of @command{guix
3325 build} allows users to check whether previously-installed substitutes
3326 are genuine by rebuilding them locally (@pxref{build-check,
3327 @command{guix build --check}}).
3329 In the future, we want Guix to have support to publish and retrieve
3330 binaries to/from other users, in a peer-to-peer fashion. If you would
3331 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3333 @node Packages with Multiple Outputs
3334 @section Packages with Multiple Outputs
3336 @cindex multiple-output packages
3337 @cindex package outputs
3340 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3341 source package leads to exactly one directory in the store. When running
3342 @command{guix install glibc}, one installs the default output of the
3343 GNU libc package; the default output is called @code{out}, but its name
3344 can be omitted as shown in this command. In this particular case, the
3345 default output of @code{glibc} contains all the C header files, shared
3346 libraries, static libraries, Info documentation, and other supporting
3349 Sometimes it is more appropriate to separate the various types of files
3350 produced from a single source package into separate outputs. For
3351 instance, the GLib C library (used by GTK+ and related packages)
3352 installs more than 20 MiB of reference documentation as HTML pages.
3353 To save space for users who do not need it, the documentation goes to a
3354 separate output, called @code{doc}. To install the main GLib output,
3355 which contains everything but the documentation, one would run:
3361 @cindex documentation
3362 The command to install its documentation is:
3365 guix install glib:doc
3368 Some packages install programs with different ``dependency footprints''.
3369 For instance, the WordNet package installs both command-line tools and
3370 graphical user interfaces (GUIs). The former depend solely on the C
3371 library, whereas the latter depend on Tcl/Tk and the underlying X
3372 libraries. In this case, we leave the command-line tools in the default
3373 output, whereas the GUIs are in a separate output. This allows users
3374 who do not need the GUIs to save space. The @command{guix size} command
3375 can help find out about such situations (@pxref{Invoking guix size}).
3376 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3378 There are several such multiple-output packages in the GNU distribution.
3379 Other conventional output names include @code{lib} for libraries and
3380 possibly header files, @code{bin} for stand-alone programs, and
3381 @code{debug} for debugging information (@pxref{Installing Debugging
3382 Files}). The outputs of a packages are listed in the third column of
3383 the output of @command{guix package --list-available} (@pxref{Invoking
3387 @node Invoking guix gc
3388 @section Invoking @command{guix gc}
3390 @cindex garbage collector
3392 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3393 The @command{guix gc} command allows users to explicitly run the garbage
3394 collector to reclaim space from the @file{/gnu/store} directory. It is
3395 the @emph{only} way to remove files from @file{/gnu/store}---removing
3396 files or directories manually may break it beyond repair!
3399 @cindex garbage collector roots
3400 The garbage collector has a set of known @dfn{roots}: any file under
3401 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3402 cannot be deleted; any other file is considered @dfn{dead} and may be
3403 deleted. The set of garbage collector roots (``GC roots'' for short)
3404 includes default user profiles; by default, the symlinks under
3405 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3406 added with @command{guix build --root}, for example (@pxref{Invoking
3407 guix build}). The @command{guix gc --list-roots} command lists them.
3409 Prior to running @code{guix gc --collect-garbage} to make space, it is
3410 often useful to remove old generations from user profiles; that way, old
3411 package builds referenced by those generations can be reclaimed. This
3412 is achieved by running @code{guix package --delete-generations}
3413 (@pxref{Invoking guix package}).
3415 Our recommendation is to run a garbage collection periodically, or when
3416 you are short on disk space. For instance, to guarantee that at least
3417 5@tie{}GB are available on your disk, simply run:
3423 It is perfectly safe to run as a non-interactive periodic job
3424 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3425 Running @command{guix gc} with no arguments will collect as
3426 much garbage as it can, but that is often inconvenient: you may find
3427 yourself having to rebuild or re-download software that is ``dead'' from
3428 the GC viewpoint but that is necessary to build other pieces of
3429 software---e.g., the compiler tool chain.
3431 The @command{guix gc} command has three modes of operation: it can be
3432 used to garbage-collect any dead files (the default), to delete specific
3433 files (the @code{--delete} option), to print garbage-collector
3434 information, or for more advanced queries. The garbage collection
3435 options are as follows:
3438 @item --collect-garbage[=@var{min}]
3439 @itemx -C [@var{min}]
3440 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3441 sub-directories. This is the default operation when no option is
3444 When @var{min} is given, stop once @var{min} bytes have been collected.
3445 @var{min} may be a number of bytes, or it may include a unit as a
3446 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3447 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3449 When @var{min} is omitted, collect all the garbage.
3451 @item --free-space=@var{free}
3452 @itemx -F @var{free}
3453 Collect garbage until @var{free} space is available under
3454 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3455 as @code{500MiB}, as described above.
3457 When @var{free} or more is already available in @file{/gnu/store}, do
3458 nothing and exit immediately.
3460 @item --delete-generations[=@var{duration}]
3461 @itemx -d [@var{duration}]
3462 Before starting the garbage collection process, delete all the generations
3463 older than @var{duration}, for all the user profiles; when run as root, this
3464 applies to all the profiles @emph{of all the users}.
3466 For example, this command deletes all the generations of all your profiles
3467 that are older than 2 months (except generations that are current), and then
3468 proceeds to free space until at least 10 GiB are available:
3471 guix gc -d 2m -F 10G
3476 Attempt to delete all the store files and directories specified as
3477 arguments. This fails if some of the files are not in the store, or if
3478 they are still live.
3480 @item --list-failures
3481 List store items corresponding to cached build failures.
3483 This prints nothing unless the daemon was started with
3484 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3485 @option{--cache-failures}}).
3488 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3491 @item --clear-failures
3492 Remove the specified store items from the failed-build cache.
3494 Again, this option only makes sense when the daemon is started with
3495 @option{--cache-failures}. Otherwise, it does nothing.
3498 Show the list of dead files and directories still present in the
3499 store---i.e., files and directories no longer reachable from any root.
3502 Show the list of live store files and directories.
3506 In addition, the references among existing store files can be queried:
3512 @cindex package dependencies
3513 List the references (respectively, the referrers) of store files given
3519 List the requisites of the store files passed as arguments. Requisites
3520 include the store files themselves, their references, and the references
3521 of these, recursively. In other words, the returned list is the
3522 @dfn{transitive closure} of the store files.
3524 @xref{Invoking guix size}, for a tool to profile the size of the closure
3525 of an element. @xref{Invoking guix graph}, for a tool to visualize
3526 the graph of references.
3530 Return the derivation(s) leading to the given store items
3531 (@pxref{Derivations}).
3533 For example, this command:
3536 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3540 returns the @file{.drv} file(s) leading to the @code{emacs} package
3541 installed in your profile.
3543 Note that there may be zero matching @file{.drv} files, for instance
3544 because these files have been garbage-collected. There can also be more
3545 than one matching @file{.drv} due to fixed-output derivations.
3548 Lastly, the following options allow you to check the integrity of the
3549 store and to control disk usage.
3553 @item --verify[=@var{options}]
3554 @cindex integrity, of the store
3555 @cindex integrity checking
3556 Verify the integrity of the store.
3558 By default, make sure that all the store items marked as valid in the
3559 database of the daemon actually exist in @file{/gnu/store}.
3561 When provided, @var{options} must be a comma-separated list containing one
3562 or more of @code{contents} and @code{repair}.
3564 When passing @option{--verify=contents}, the daemon computes the
3565 content hash of each store item and compares it against its hash in the
3566 database. Hash mismatches are reported as data corruptions. Because it
3567 traverses @emph{all the files in the store}, this command can take a
3568 long time, especially on systems with a slow disk drive.
3570 @cindex repairing the store
3571 @cindex corruption, recovering from
3572 Using @option{--verify=repair} or @option{--verify=contents,repair}
3573 causes the daemon to try to repair corrupt store items by fetching
3574 substitutes for them (@pxref{Substitutes}). Because repairing is not
3575 atomic, and thus potentially dangerous, it is available only to the
3576 system administrator. A lightweight alternative, when you know exactly
3577 which items in the store are corrupt, is @command{guix build --repair}
3578 (@pxref{Invoking guix build}).
3581 @cindex deduplication
3582 Optimize the store by hard-linking identical files---this is
3583 @dfn{deduplication}.
3585 The daemon performs deduplication after each successful build or archive
3586 import, unless it was started with @code{--disable-deduplication}
3587 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3588 this option is primarily useful when the daemon was running with
3589 @code{--disable-deduplication}.
3593 @node Invoking guix pull
3594 @section Invoking @command{guix pull}
3596 @cindex upgrading Guix
3597 @cindex updating Guix
3598 @cindex @command{guix pull}
3600 Packages are installed or upgraded to the latest version available in
3601 the distribution currently available on your local machine. To update
3602 that distribution, along with the Guix tools, you must run @command{guix
3603 pull}: the command downloads the latest Guix source code and package
3604 descriptions, and deploys it. Source code is downloaded from a
3605 @uref{https://git-scm.com, Git} repository, by default the official
3606 GNU@tie{}Guix repository, though this can be customized.
3608 On completion, @command{guix package} will use packages and package
3609 versions from this just-retrieved copy of Guix. Not only that, but all
3610 the Guix commands and Scheme modules will also be taken from that latest
3611 version. New @command{guix} sub-commands added by the update also
3614 Any user can update their Guix copy using @command{guix pull}, and the
3615 effect is limited to the user who run @command{guix pull}. For
3616 instance, when user @code{root} runs @command{guix pull}, this has no
3617 effect on the version of Guix that user @code{alice} sees, and vice
3620 The result of running @command{guix pull} is a @dfn{profile} available
3621 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3622 make sure to add it to the beginning of your search path so that you use
3623 the latest version, and similarly for the Info manual
3624 (@pxref{Documentation}):
3627 export PATH="$HOME/.config/guix/current/bin:$PATH"
3628 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3631 The @code{--list-generations} or @code{-l} option lists past generations
3632 produced by @command{guix pull}, along with details about their provenance:
3636 Generation 1 Jun 10 2018 00:18:18
3638 repository URL: https://git.savannah.gnu.org/git/guix.git
3639 branch: origin/master
3640 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3642 Generation 2 Jun 11 2018 11:02:49
3644 repository URL: https://git.savannah.gnu.org/git/guix.git
3645 branch: origin/master
3646 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3647 2 new packages: keepalived, libnfnetlink
3648 6 packages upgraded: emacs-nix-mode@@2.0.4,
3649 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3650 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3652 Generation 3 Jun 13 2018 23:31:07 (current)
3654 repository URL: https://git.savannah.gnu.org/git/guix.git
3655 branch: origin/master
3656 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3657 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3658 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3661 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3662 describe the current status of Guix.
3664 This @code{~/.config/guix/current} profile works like any other profile
3665 created by @command{guix package} (@pxref{Invoking guix package}). That
3666 is, you can list generations, roll back to the previous
3667 generation---i.e., the previous Guix---and so on:
3670 $ guix package -p ~/.config/guix/current --roll-back
3671 switched from generation 3 to 2
3672 $ guix package -p ~/.config/guix/current --delete-generations=1
3673 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3676 The @command{guix pull} command is usually invoked with no arguments,
3677 but it supports the following options:
3680 @item --url=@var{url}
3681 @itemx --commit=@var{commit}
3682 @itemx --branch=@var{branch}
3683 Download code for the @code{guix} channel from the specified @var{url}, at the
3684 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3685 string), or @var{branch}.
3687 @cindex @file{channels.scm}, configuration file
3688 @cindex configuration file for channels
3689 These options are provided for convenience, but you can also specify your
3690 configuration in the @file{~/.config/guix/channels.scm} file or using the
3691 @option{--channels} option (see below).
3693 @item --channels=@var{file}
3694 @itemx -C @var{file}
3695 Read the list of channels from @var{file} instead of
3696 @file{~/.config/guix/channels.scm}. @var{file} must contain Scheme code that
3697 evaluates to a list of channel objects. @xref{Channels}, for more
3702 Display the list of packages added or upgraded since the previous generation.
3704 This is the same information as displayed upon @command{guix pull} completion,
3705 but without ellipses; it is also similar to the output of @command{guix pull
3706 -l} for the last generation (see below).
3708 @item --list-generations[=@var{pattern}]
3709 @itemx -l [@var{pattern}]
3710 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3711 is provided, the subset of generations that match @var{pattern}.
3712 The syntax of @var{pattern} is the same as with @code{guix package
3713 --list-generations} (@pxref{Invoking guix package}).
3715 @xref{Invoking guix describe}, for a way to display information about the
3716 current generation only.
3718 @item --profile=@var{profile}
3719 @itemx -p @var{profile}
3720 Use @var{profile} instead of @file{~/.config/guix/current}.
3724 Show which channel commit(s) would be used and what would be built or
3725 substituted but do not actually do it.
3727 @item --system=@var{system}
3728 @itemx -s @var{system}
3729 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3730 the system type of the build host.
3733 Produce verbose output, writing build logs to the standard error output.
3736 Use the bootstrap Guile to build the latest Guix. This option is only
3737 useful to Guix developers.
3740 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3741 repository and branch to pull from, as well as @emph{additional} repositories
3742 containing package modules that should be deployed. @xref{Channels}, for more
3745 In addition, @command{guix pull} supports all the common build options
3746 (@pxref{Common Build Options}).
3752 @cindex @file{channels.scm}, configuration file
3753 @cindex configuration file for channels
3754 @cindex @command{guix pull}, configuration file
3755 @cindex configuration of @command{guix pull}
3756 Guix and its package collection are updated by running @command{guix pull}
3757 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3758 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3759 customized by defining @dfn{channels} in the
3760 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3761 of a Git repository to be deployed, and @command{guix pull} can be instructed
3762 to pull from one or more channels. In other words, channels can be used to
3763 @emph{customize} and to @emph{extend} Guix, as we will see below.
3765 @subsection Using a Custom Guix Channel
3767 The channel called @code{guix} specifies where Guix itself---its command-line
3768 tools as well as its package collection---should be downloaded. For instance,
3769 suppose you want to update from your own copy of the Guix repository at
3770 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3771 write in @code{~/.config/guix/channels.scm} this specification:
3774 ;; Tell 'guix pull' to use my own repo.
3777 (url "https://example.org/my-guix.git")
3778 (branch "super-hacks")))
3782 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3783 branch of the repository at @code{example.org}.
3785 @subsection Specifying Additional Channels
3787 @cindex extending the package collection (channels)
3788 @cindex personal packages (channels)
3789 @cindex channels, for personal packages
3790 You can also specify @emph{additional channels} to pull from. Let's say you
3791 have a bunch of custom package variants or personal packages that you think
3792 would make little sense to contribute to the Guix project, but would like to
3793 have these packages transparently available to you at the command line. You
3794 would first write modules containing those package definitions (@pxref{Package
3795 Modules}), maintain them in a Git repository, and then you and anyone else can
3796 use it as an additional channel to get packages from. Neat, no?
3798 @c What follows stems from discussions at
3799 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3800 @c earlier discussions on guix-devel@gnu.org.
3802 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3803 publish your personal channel to the world, we would like to share a few words
3808 Before publishing a channel, please consider contributing your package
3809 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3810 to free software of all sorts, and packages in Guix proper are readily
3811 available to all Guix users and benefit from the project's quality assurance
3815 When you maintain package definitions outside Guix, we, Guix developers,
3816 consider that @emph{the compatibility burden is on you}. Remember that
3817 package modules and package definitions are just Scheme code that uses various
3818 programming interfaces (APIs). We want to remain free to change these APIs to
3819 keep improving Guix, possibly in ways that break your channel. We never
3820 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
3824 Corollary: if you're using an external channel and that channel breaks, please
3825 @emph{report the issue to the channel authors}, not to the Guix project.
3828 You've been warned! Having said this, we believe external channels are a
3829 practical way to exert your freedom to augment Guix' package collection and to
3830 share your improvements, which are basic tenets of
3831 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
3832 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
3835 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
3836 @command{guix pull} to pull from it @emph{in addition} to the default Guix
3839 @vindex %default-channels
3841 ;; Add my personal packages to those Guix provides.
3843 (name 'my-personal-packages)
3844 (url "https://example.org/personal-packages.git"))
3849 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
3850 add a channel the list of channels that the variable @code{%default-channels}
3851 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
3852 Manual}). With this file in place, @command{guix pull} builds not only Guix
3853 but also the package modules from your own repository. The result in
3854 @file{~/.config/guix/current} is the union of Guix with your own package
3858 $ guix pull --list-generations
3860 Generation 19 Aug 27 2018 16:20:48
3862 repository URL: https://git.savannah.gnu.org/git/guix.git
3864 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
3865 my-personal-packages dd3df5e
3866 repository URL: https://example.org/personal-packages.git
3868 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
3869 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
3870 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
3874 The output of @command{guix pull} above shows that Generation@tie{}19 includes
3875 both Guix and packages from the @code{my-personal-packages} channel. Among
3876 the new and upgraded packages that are listed, some like @code{my-gimp} and
3877 @code{my-emacs-with-cool-features} might come from
3878 @code{my-personal-packages}, while others come from the Guix default channel.
3880 To create a channel, create a Git repository containing your own package
3881 modules and make it available. The repository can contain anything, but a
3882 useful channel will contain Guile modules that export packages. Once you
3883 start using a channel, Guix will behave as if the root directory of that
3884 channel's Git repository has been added to the Guile load path (@pxref{Load
3885 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
3886 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
3887 module, then the module will be available under the name @code{(my-packages
3888 my-tools)}, and you will be able to use it like any other module
3889 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
3891 @cindex dependencies, channels
3892 @cindex meta-data, channels
3893 @subsection Declaring Channel Dependencies
3895 Channel authors may decide to augment a package collection provided by other
3896 channels. They can declare their channel to be dependent on other channels in
3897 a meta-data file @file{.guix-channel}, which is to be placed in the root of
3898 the channel repository.
3900 The meta-data file should contain a simple S-expression like this:
3907 (name some-collection)
3908 (url "https://example.org/first-collection.git"))
3910 (name some-other-collection)
3911 (url "https://example.org/second-collection.git")
3912 (branch "testing"))))
3915 In the above example this channel is declared to depend on two other channels,
3916 which will both be fetched automatically. The modules provided by the channel
3917 will be compiled in an environment where the modules of all these declared
3918 channels are available.
3920 For the sake of reliability and maintainability, you should avoid dependencies
3921 on channels that you don't control, and you should aim to keep the number of
3922 dependencies to a minimum.
3924 @subsection Replicating Guix
3926 @cindex pinning, channels
3927 @cindex replicating Guix
3928 @cindex reproducibility, of Guix
3929 The @command{guix pull --list-generations} output above shows precisely which
3930 commits were used to build this instance of Guix. We can thus replicate it,
3931 say, on another machine, by providing a channel specification in
3932 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
3935 ;; Deploy specific commits of my channels of interest.
3938 (url "https://git.savannah.gnu.org/git/guix.git")
3939 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
3941 (name 'my-personal-packages)
3942 (url "https://example.org/personal-packages.git")
3943 (branch "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
3946 The @command{guix describe --format=channels} command can even generate this
3947 list of channels directly (@pxref{Invoking guix describe}).
3949 At this point the two machines run the @emph{exact same Guix}, with access to
3950 the @emph{exact same packages}. The output of @command{guix build gimp} on
3951 one machine will be exactly the same, bit for bit, as the output of the same
3952 command on the other machine. It also means both machines have access to all
3953 the source code of Guix and, transitively, to all the source code of every
3956 This gives you super powers, allowing you to track the provenance of binary
3957 artifacts with very fine grain, and to reproduce software environments at
3958 will---some sort of ``meta reproducibility'' capabilities, if you will.
3959 @xref{Inferiors}, for another way to take advantage of these super powers.
3964 @c TODO: Remove this once we're more confident about API stability.
3966 The functionality described here is a ``technology preview'' as of version
3967 @value{VERSION}. As such, the interface is subject to change.
3971 @cindex composition of Guix revisions
3972 Sometimes you might need to mix packages from the revision of Guix you're
3973 currently running with packages available in a different revision of Guix.
3974 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
3975 revisions in arbitrary ways.
3977 @cindex inferior packages
3978 Technically, an ``inferior'' is essentially a separate Guix process connected
3979 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
3980 @code{(guix inferior)} module allows you to create inferiors and to
3981 communicate with them. It also provides a high-level interface to browse and
3982 manipulate the packages that an inferior provides---@dfn{inferior packages}.
3984 When combined with channels (@pxref{Channels}), inferiors provide a simple way
3985 to interact with a separate revision of Guix. For example, let's assume you
3986 want to install in your profile the current @code{guile} package, along with
3987 the @code{guile-json} as it existed in an older revision of Guix---perhaps
3988 because the newer @code{guile-json} has an incompatible API and you want to
3989 run your code against the old API@. To do that, you could write a manifest for
3990 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
3991 manifest, you would create an inferior for that old Guix revision you care
3992 about, and you would look up the @code{guile-json} package in the inferior:
3995 (use-modules (guix inferior) (guix channels)
3996 (srfi srfi-1)) ;for 'first'
3999 ;; This is the old revision from which we want to
4000 ;; extract guile-json.
4003 (url "https://git.savannah.gnu.org/git/guix.git")
4005 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4008 ;; An inferior representing the above revision.
4009 (inferior-for-channels channels))
4011 ;; Now create a manifest with the current "guile" package
4012 ;; and the old "guile-json" package.
4014 (list (first (lookup-inferior-packages inferior "guile-json"))
4015 (specification->package "guile")))
4018 On its first run, @command{guix package --manifest} might have to build the
4019 channel you specified before it can create the inferior; subsequent runs will
4020 be much faster because the Guix revision will be cached.
4022 The @code{(guix inferior)} module provides the following procedures to open an
4025 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4026 [#:cache-directory] [#:ttl]
4027 Return an inferior for @var{channels}, a list of channels. Use the cache at
4028 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4029 This procedure opens a new connection to the build daemon.
4031 As a side effect, this procedure may build or substitute binaries for
4032 @var{channels}, which can take time.
4035 @deffn {Scheme Procedure} open-inferior @var{directory} @
4036 [#:command "bin/guix"]
4037 Open the inferior Guix in @var{directory}, running
4038 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4039 the inferior could not be launched.
4042 @cindex inferior packages
4043 The procedures listed below allow you to obtain and manipulate inferior
4046 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4047 Return the list of packages known to @var{inferior}.
4050 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4052 Return the sorted list of inferior packages matching @var{name} in
4053 @var{inferior}, with highest version numbers first. If @var{version} is true,
4054 return only packages with a version number prefixed by @var{version}.
4057 @deffn {Scheme Procedure} inferior-package? @var{obj}
4058 Return true if @var{obj} is an inferior package.
4061 @deffn {Scheme Procedure} inferior-package-name @var{package}
4062 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4063 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4064 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4065 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4066 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4067 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4068 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4069 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4070 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4071 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4072 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4073 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4074 These procedures are the counterpart of package record accessors
4075 (@pxref{package Reference}). Most of them work by querying the inferior
4076 @var{package} comes from, so the inferior must still be live when you call
4080 Inferior packages can be used transparently like any other package or
4081 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4082 transparently handled by the @code{packages->manifest} procedure, which is
4083 commonly use in manifests (@pxref{Invoking guix package, the
4084 @option{--manifest} option of @command{guix package}}). Thus you can insert
4085 an inferior package pretty much anywhere you would insert a regular package:
4086 in manifests, in the @code{packages} field of your @code{operating-system}
4087 declaration, and so on.
4089 @node Invoking guix describe
4090 @section Invoking @command{guix describe}
4092 @cindex reproducibility
4093 @cindex replicating Guix
4094 Often you may want to answer questions like: ``Which revision of Guix am I
4095 using?'' or ``Which channels am I using?'' This is useful information in many
4096 situations: if you want to @emph{replicate} an environment on a different
4097 machine or user account, if you want to report a bug or to determine what
4098 change in the channels you are using caused it, or if you want to record your
4099 system state for reproducibility purposes. The @command{guix describe}
4100 command answers these questions.
4102 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4103 displays the channel(s) that it was built from, including their repository URL
4104 and commit IDs (@pxref{Channels}):
4108 Generation 10 Sep 03 2018 17:32:44 (current)
4110 repository URL: https://git.savannah.gnu.org/git/guix.git
4112 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4115 If you're familiar with the Git version control system, this is similar in
4116 spirit to @command{git describe}; the output is also similar to that of
4117 @command{guix pull --list-generations}, but limited to the current generation
4118 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4119 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4120 information is all it takes to describe the revision of Guix you're using, and
4121 also to replicate it.
4123 To make it easier to replicate Guix, @command{guix describe} can also be asked
4124 to return a list of channels instead of the human-readable description above:
4127 $ guix describe -f channels
4130 (url "https://git.savannah.gnu.org/git/guix.git")
4132 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4136 You can save this to a file and feed it to @command{guix pull -C} on some
4137 other machine or at a later point in time, which will instantiate @emph{this
4138 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4139 From there on, since you're able to deploy the same revision of Guix, you can
4140 just as well @emph{replicate a complete software environment}. We humbly
4141 think that this is @emph{awesome}, and we hope you'll like it too!
4143 The details of the options supported by @command{guix describe} are as
4147 @item --format=@var{format}
4148 @itemx -f @var{format}
4149 Produce output in the specified @var{format}, one of:
4153 produce human-readable output;
4155 produce a list of channel specifications that can be passed to @command{guix
4156 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4160 produce a list of channel specifications in JSON format;
4162 produce a list of channel specifications in Recutils format.
4165 @item --profile=@var{profile}
4166 @itemx -p @var{profile}
4167 Display information about @var{profile}.
4170 @node Invoking guix archive
4171 @section Invoking @command{guix archive}
4173 @cindex @command{guix archive}
4175 The @command{guix archive} command allows users to @dfn{export} files
4176 from the store into a single archive, and to later @dfn{import} them on
4177 a machine that runs Guix.
4178 In particular, it allows store files to be transferred from one machine
4179 to the store on another machine.
4182 If you're looking for a way to produce archives in a format suitable for
4183 tools other than Guix, @pxref{Invoking guix pack}.
4186 @cindex exporting store items
4187 To export store files as an archive to standard output, run:
4190 guix archive --export @var{options} @var{specifications}...
4193 @var{specifications} may be either store file names or package
4194 specifications, as for @command{guix package} (@pxref{Invoking guix
4195 package}). For instance, the following command creates an archive
4196 containing the @code{gui} output of the @code{git} package and the main
4197 output of @code{emacs}:
4200 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4203 If the specified packages are not built yet, @command{guix archive}
4204 automatically builds them. The build process may be controlled with the
4205 common build options (@pxref{Common Build Options}).
4207 To transfer the @code{emacs} package to a machine connected over SSH,
4211 guix archive --export -r emacs | ssh the-machine guix archive --import
4215 Similarly, a complete user profile may be transferred from one machine
4216 to another like this:
4219 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4220 ssh the-machine guix archive --import
4224 However, note that, in both examples, all of @code{emacs} and the
4225 profile as well as all of their dependencies are transferred (due to
4226 @code{-r}), regardless of what is already available in the store on the
4227 target machine. The @code{--missing} option can help figure out which
4228 items are missing from the target store. The @command{guix copy}
4229 command simplifies and optimizes this whole process, so this is probably
4230 what you should use in this case (@pxref{Invoking guix copy}).
4232 @cindex nar, archive format
4233 @cindex normalized archive (nar)
4234 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4235 comparable in spirit to `tar', but with differences
4236 that make it more appropriate for our purposes. First, rather than
4237 recording all Unix metadata for each file, the nar format only mentions
4238 the file type (regular, directory, or symbolic link); Unix permissions
4239 and owner/group are dismissed. Second, the order in which directory
4240 entries are stored always follows the order of file names according to
4241 the C locale collation order. This makes archive production fully
4244 When exporting, the daemon digitally signs the contents of the archive,
4245 and that digital signature is appended. When importing, the daemon
4246 verifies the signature and rejects the import in case of an invalid
4247 signature or if the signing key is not authorized.
4248 @c FIXME: Add xref to daemon doc about signatures.
4250 The main options are:
4254 Export the specified store files or packages (see below.) Write the
4255 resulting archive to the standard output.
4257 Dependencies are @emph{not} included in the output, unless
4258 @code{--recursive} is passed.
4262 When combined with @code{--export}, this instructs @command{guix
4263 archive} to include dependencies of the given items in the archive.
4264 Thus, the resulting archive is self-contained: it contains the closure
4265 of the exported store items.
4268 Read an archive from the standard input, and import the files listed
4269 therein into the store. Abort if the archive has an invalid digital
4270 signature, or if it is signed by a public key not among the authorized
4271 keys (see @code{--authorize} below.)
4274 Read a list of store file names from the standard input, one per line,
4275 and write on the standard output the subset of these files missing from
4278 @item --generate-key[=@var{parameters}]
4279 @cindex signing, archives
4280 Generate a new key pair for the daemon. This is a prerequisite before
4281 archives can be exported with @code{--export}. Note that this operation
4282 usually takes time, because it needs to gather enough entropy to
4283 generate the key pair.
4285 The generated key pair is typically stored under @file{/etc/guix}, in
4286 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4287 key, which must be kept secret.) When @var{parameters} is omitted,
4288 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4289 versions before 1.6.0, it is a 4096-bit RSA key.
4290 Alternatively, @var{parameters} can specify
4291 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4292 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4293 Libgcrypt Reference Manual}).
4296 @cindex authorizing, archives
4297 Authorize imports signed by the public key passed on standard input.
4298 The public key must be in ``s-expression advanced format''---i.e., the
4299 same format as the @file{signing-key.pub} file.
4301 The list of authorized keys is kept in the human-editable file
4302 @file{/etc/guix/acl}. The file contains
4303 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4304 s-expressions''} and is structured as an access-control list in the
4305 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4308 @item --extract=@var{directory}
4309 @itemx -x @var{directory}
4310 Read a single-item archive as served by substitute servers
4311 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4312 low-level operation needed in only very narrow use cases; see below.
4314 For example, the following command extracts the substitute for Emacs
4315 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4319 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-emacs-24.5 \
4320 | bunzip2 | guix archive -x /tmp/emacs
4323 Single-item archives are different from multiple-item archives produced
4324 by @command{guix archive --export}; they contain a single store item,
4325 and they do @emph{not} embed a signature. Thus this operation does
4326 @emph{no} signature verification and its output should be considered
4329 The primary purpose of this operation is to facilitate inspection of
4330 archive contents coming from possibly untrusted substitute servers.
4335 @c *********************************************************************
4337 @chapter Development
4339 @cindex software development
4340 If you are a software developer, Guix provides tools that you should find
4341 helpful---independently of the language you're developing in. This is what
4342 this chapter is about.
4344 The @command{guix environment} command provides a convenient way to set up
4345 @dfn{development environments} containing all the dependencies and tools
4346 necessary to work on the software package of your choice. The @command{guix
4347 pack} command allows you to create @dfn{application bundles} that can be
4348 easily distributed to users who do not run Guix.
4351 * Invoking guix environment:: Setting up development environments.
4352 * Invoking guix pack:: Creating software bundles.
4355 @node Invoking guix environment
4356 @section Invoking @command{guix environment}
4358 @cindex reproducible build environments
4359 @cindex development environments
4360 @cindex @command{guix environment}
4361 @cindex environment, package build environment
4362 The purpose of @command{guix environment} is to assist hackers in
4363 creating reproducible development environments without polluting their
4364 package profile. The @command{guix environment} tool takes one or more
4365 packages, builds all of their inputs, and creates a shell
4366 environment to use them.
4368 The general syntax is:
4371 guix environment @var{options} @var{package}@dots{}
4374 The following example spawns a new shell set up for the development of
4378 guix environment guile
4381 If the needed dependencies are not built yet, @command{guix environment}
4382 automatically builds them. The environment of the new shell is an augmented
4383 version of the environment that @command{guix environment} was run in.
4384 It contains the necessary search paths for building the given package
4385 added to the existing environment variables. To create a ``pure''
4386 environment, in which the original environment variables have been unset,
4387 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4388 environment variables such as @code{PATH} in their @file{~/.bashrc}
4389 file. As a consequence, when @code{guix environment} launches it, Bash
4390 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4391 environment variables. It is an error to define such environment
4392 variables in @file{.bashrc}; instead, they should be defined in
4393 @file{.bash_profile}, which is sourced only by log-in shells.
4394 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4395 details on Bash start-up files.}.
4397 @vindex GUIX_ENVIRONMENT
4398 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4399 variable in the shell it spawns; its value is the file name of the
4400 profile of this environment. This allows users to, say, define a
4401 specific prompt for development environments in their @file{.bashrc}
4402 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4405 if [ -n "$GUIX_ENVIRONMENT" ]
4407 export PS1="\u@@\h \w [dev]\$ "
4412 ...@: or to browse the profile:
4415 $ ls "$GUIX_ENVIRONMENT/bin"
4418 Additionally, more than one package may be specified, in which case the
4419 union of the inputs for the given packages are used. For example, the
4420 command below spawns a shell where all of the dependencies of both Guile
4421 and Emacs are available:
4424 guix environment guile emacs
4427 Sometimes an interactive shell session is not desired. An arbitrary
4428 command may be invoked by placing the @code{--} token to separate the
4429 command from the rest of the arguments:
4432 guix environment guile -- make -j4
4435 In other situations, it is more convenient to specify the list of
4436 packages needed in the environment. For example, the following command
4437 runs @command{python} from an environment containing Python@tie{}2.7 and
4441 guix environment --ad-hoc python2-numpy python-2.7 -- python
4444 Furthermore, one might want the dependencies of a package and also some
4445 additional packages that are not build-time or runtime dependencies, but
4446 are useful when developing nonetheless. Because of this, the
4447 @code{--ad-hoc} flag is positional. Packages appearing before
4448 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4449 added to the environment. Packages appearing after are interpreted as
4450 packages that will be added to the environment directly. For example,
4451 the following command creates a Guix development environment that
4452 additionally includes Git and strace:
4455 guix environment guix --ad-hoc git strace
4458 Sometimes it is desirable to isolate the environment as much as
4459 possible, for maximal purity and reproducibility. In particular, when
4460 using Guix on a host distro that is not Guix System, it is desirable to
4461 prevent access to @file{/usr/bin} and other system-wide resources from
4462 the development environment. For example, the following command spawns
4463 a Guile REPL in a ``container'' where only the store and the current
4464 working directory are mounted:
4467 guix environment --ad-hoc --container guile -- guile
4471 The @code{--container} option requires Linux-libre 3.19 or newer.
4474 The available options are summarized below.
4477 @item --root=@var{file}
4478 @itemx -r @var{file}
4479 @cindex persistent environment
4480 @cindex garbage collector root, for environments
4481 Make @var{file} a symlink to the profile for this environment, and
4482 register it as a garbage collector root.
4484 This is useful if you want to protect your environment from garbage
4485 collection, to make it ``persistent''.
4487 When this option is omitted, the environment is protected from garbage
4488 collection only for the duration of the @command{guix environment}
4489 session. This means that next time you recreate the same environment,
4490 you could have to rebuild or re-download packages. @xref{Invoking guix
4491 gc}, for more on GC roots.
4493 @item --expression=@var{expr}
4494 @itemx -e @var{expr}
4495 Create an environment for the package or list of packages that
4496 @var{expr} evaluates to.
4498 For example, running:
4501 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4504 starts a shell with the environment for this specific variant of the
4510 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4513 starts a shell with all the base system packages available.
4515 The above commands only use the default output of the given packages.
4516 To select other outputs, two element tuples can be specified:
4519 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4522 @item --load=@var{file}
4523 @itemx -l @var{file}
4524 Create an environment for the package or list of packages that the code
4525 within @var{file} evaluates to.
4527 As an example, @var{file} might contain a definition like this
4528 (@pxref{Defining Packages}):
4531 @verbatiminclude environment-gdb.scm
4534 @item --manifest=@var{file}
4535 @itemx -m @var{file}
4536 Create an environment for the packages contained in the manifest object
4537 returned by the Scheme code in @var{file}.
4539 This is similar to the same-named option in @command{guix package}
4540 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4544 Include all specified packages in the resulting environment, as if an
4545 @i{ad hoc} package were defined with them as inputs. This option is
4546 useful for quickly creating an environment without having to write a
4547 package expression to contain the desired inputs.
4549 For instance, the command:
4552 guix environment --ad-hoc guile guile-sdl -- guile
4555 runs @command{guile} in an environment where Guile and Guile-SDL are
4558 Note that this example implicitly asks for the default output of
4559 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4560 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4561 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4563 This option may be composed with the default behavior of @command{guix
4564 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4565 as packages whose dependencies will be added to the environment, the
4566 default behavior. Packages appearing after are interpreted as packages
4567 that will be added to the environment directly.
4570 Unset existing environment variables when building the new environment, except
4571 those specified with @option{--preserve} (see below.) This has the effect of
4572 creating an environment in which search paths only contain package inputs.
4574 @item --preserve=@var{regexp}
4575 @itemx -E @var{regexp}
4576 When used alongside @option{--pure}, preserve the environment variables
4577 matching @var{regexp}---in other words, put them on a ``white list'' of
4578 environment variables that must be preserved. This option can be repeated
4582 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4586 This example runs @command{mpirun} in a context where the only environment
4587 variables defined are @code{PATH}, environment variables whose name starts
4588 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4591 @item --search-paths
4592 Display the environment variable definitions that make up the
4595 @item --system=@var{system}
4596 @itemx -s @var{system}
4597 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4602 Run @var{command} within an isolated container. The current working
4603 directory outside the container is mapped inside the container.
4604 Additionally, unless overridden with @code{--user}, a dummy home
4605 directory is created that matches the current user's home directory, and
4606 @file{/etc/passwd} is configured accordingly.
4608 The spawned process runs as the current user outside the container. Inside
4609 the container, it has the same UID and GID as the current user, unless
4610 @option{--user} is passed (see below.)
4614 For containers, share the network namespace with the host system.
4615 Containers created without this flag only have access to the loopback
4618 @item --link-profile
4620 For containers, link the environment profile to
4621 @file{~/.guix-profile} within the container. This is equivalent to
4622 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4623 within the container. Linking will fail and abort the environment if
4624 the directory already exists, which will certainly be the case if
4625 @command{guix environment} was invoked in the user's home directory.
4627 Certain packages are configured to look in
4628 @code{~/.guix-profile} for configuration files and data;@footnote{For
4629 example, the @code{fontconfig} package inspects
4630 @file{~/.guix-profile/share/fonts} for additional fonts.}
4631 @code{--link-profile} allows these programs to behave as expected within
4634 @item --user=@var{user}
4635 @itemx -u @var{user}
4636 For containers, use the username @var{user} in place of the current
4637 user. The generated @file{/etc/passwd} entry within the container will
4638 contain the name @var{user}, the home directory will be
4639 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4640 the UID and GID inside the container are 1000. @var{user}
4641 need not exist on the system.
4643 Additionally, any shared or exposed path (see @code{--share} and
4644 @code{--expose} respectively) whose target is within the current user's
4645 home directory will be remapped relative to @file{/home/USER}; this
4646 includes the automatic mapping of the current working directory.
4649 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4651 guix environment --container --user=foo \
4652 --expose=$HOME/test \
4653 --expose=/tmp/target=$HOME/target
4656 While this will limit the leaking of user identity through home paths
4657 and each of the user fields, this is only one useful component of a
4658 broader privacy/anonymity solution---not one in and of itself.
4660 @item --expose=@var{source}[=@var{target}]
4661 For containers, expose the file system @var{source} from the host system
4662 as the read-only file system @var{target} within the container. If
4663 @var{target} is not specified, @var{source} is used as the target mount
4664 point in the container.
4666 The example below spawns a Guile REPL in a container in which the user's
4667 home directory is accessible read-only via the @file{/exchange}
4671 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
4674 @item --share=@var{source}[=@var{target}]
4675 For containers, share the file system @var{source} from the host system
4676 as the writable file system @var{target} within the container. If
4677 @var{target} is not specified, @var{source} is used as the target mount
4678 point in the container.
4680 The example below spawns a Guile REPL in a container in which the user's
4681 home directory is accessible for both reading and writing via the
4682 @file{/exchange} directory:
4685 guix environment --container --share=$HOME=/exchange --ad-hoc guile -- guile
4689 @command{guix environment}
4690 also supports all of the common build options that @command{guix
4691 build} supports (@pxref{Common Build Options}) as well as package
4692 transformation options (@pxref{Package Transformation Options}).
4694 @node Invoking guix pack
4695 @section Invoking @command{guix pack}
4697 Occasionally you want to pass software to people who are not (yet!)
4698 lucky enough to be using Guix. You'd tell them to run @command{guix
4699 package -i @var{something}}, but that's not possible in this case. This
4700 is where @command{guix pack} comes in.
4703 If you are looking for ways to exchange binaries among machines that
4704 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
4705 publish}, and @ref{Invoking guix archive}.
4710 @cindex application bundle
4711 @cindex software bundle
4712 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
4713 @dfn{software bundle}: it creates a tarball or some other archive
4714 containing the binaries of the software you're interested in, and all
4715 its dependencies. The resulting archive can be used on any machine that
4716 does not have Guix, and people can run the exact same binaries as those
4717 you have with Guix. The pack itself is created in a bit-reproducible
4718 fashion, so anyone can verify that it really contains the build results
4719 that you pretend to be shipping.
4721 For example, to create a bundle containing Guile, Emacs, Geiser, and all
4722 their dependencies, you can run:
4725 $ guix pack guile emacs geiser
4727 /gnu/store/@dots{}-pack.tar.gz
4730 The result here is a tarball containing a @file{/gnu/store} directory
4731 with all the relevant packages. The resulting tarball contains a
4732 @dfn{profile} with the three packages of interest; the profile is the
4733 same as would be created by @command{guix package -i}. It is this
4734 mechanism that is used to create Guix's own standalone binary tarball
4735 (@pxref{Binary Installation}).
4737 Users of this pack would have to run
4738 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
4739 find inconvenient. To work around it, you can create, say, a
4740 @file{/opt/gnu/bin} symlink to the profile:
4743 guix pack -S /opt/gnu/bin=bin guile emacs geiser
4747 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
4749 @cindex relocatable binaries, with @command{guix pack}
4750 What if the recipient of your pack does not have root privileges on
4751 their machine, and thus cannot unpack it in the root file system? In
4752 that case, you will want to use the @code{--relocatable} option (see
4753 below). This option produces @dfn{relocatable binaries}, meaning they
4754 they can be placed anywhere in the file system hierarchy: in the example
4755 above, users can unpack your tarball in their home directory and
4756 directly run @file{./opt/gnu/bin/guile}.
4758 @cindex Docker, build an image with guix pack
4759 Alternatively, you can produce a pack in the Docker image format using
4760 the following command:
4763 guix pack -f docker guile emacs geiser
4767 The result is a tarball that can be passed to the @command{docker load}
4769 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
4770 documentation} for more information.
4772 @cindex Singularity, build an image with guix pack
4773 @cindex SquashFS, build an image with guix pack
4774 Yet another option is to produce a SquashFS image with the following
4778 guix pack -f squashfs guile emacs geiser
4782 The result is a SquashFS file system image that can either be mounted or
4783 directly be used as a file system container image with the
4784 @uref{https://singularity.lbl.gov, Singularity container execution
4785 environment}, using commands like @command{singularity shell} or
4786 @command{singularity exec}.
4788 Several command-line options allow you to customize your pack:
4791 @item --format=@var{format}
4792 @itemx -f @var{format}
4793 Produce a pack in the given @var{format}.
4795 The available formats are:
4799 This is the default format. It produces a tarball containing all the
4800 specified binaries and symlinks.
4803 This produces a tarball that follows the
4804 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
4805 Docker Image Specification}.
4808 This produces a SquashFS image containing all the specified binaries and
4809 symlinks, as well as empty mount points for virtual file systems like
4813 @cindex relocatable binaries
4816 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
4817 anywhere in the file system hierarchy and run from there.
4819 When this option is passed once, the resulting binaries require support for
4820 @dfn{user namespaces} in the kernel Linux; when passed
4821 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
4822 PRoot support, can be thought of as the abbreviation of ``Really
4823 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
4824 if user namespaces are unavailable, and essentially work anywhere---see below
4825 for the implications.
4827 For example, if you create a pack containing Bash with:
4830 guix pack -RR -S /mybin=bin bash
4834 ...@: you can copy that pack to a machine that lacks Guix, and from your
4835 home directory as a normal user, run:
4843 In that shell, if you type @code{ls /gnu/store}, you'll notice that
4844 @file{/gnu/store} shows up and contains all the dependencies of
4845 @code{bash}, even though the machine actually lacks @file{/gnu/store}
4846 altogether! That is probably the simplest way to deploy Guix-built
4847 software on a non-Guix machine.
4850 By default, relocatable binaries rely on the @dfn{user namespace} feature of
4851 the kernel Linux, which allows unprivileged users to mount or change root.
4852 Old versions of Linux did not support it, and some GNU/Linux distributions
4855 To produce relocatable binaries that work even in the absence of user
4856 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
4857 case, binaries will try user namespace support and fall back to PRoot if user
4858 namespaces are not supported.
4860 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
4861 support for file system virtualization. It achieves that by using the
4862 @code{ptrace} system call on the running program. This approach has the
4863 advantage to work without requiring special kernel support, but it incurs
4864 run-time overhead every time a system call is made.
4867 @cindex entry point, for Docker images
4868 @item --entry-point=@var{command}
4869 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
4870 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
4871 support it. @var{command} must be relative to the profile contained in the
4874 The entry point specifies the command that tools like @code{docker run} or
4875 @code{singularity run} automatically start by default. For example, you can
4879 guix pack -f docker --entry-point=bin/guile guile
4882 The resulting pack can easily be loaded and @code{docker run} with no extra
4883 arguments will spawn @code{bin/guile}:
4886 docker load -i pack.tar.gz
4887 docker run @var{image-id}
4890 @item --expression=@var{expr}
4891 @itemx -e @var{expr}
4892 Consider the package @var{expr} evaluates to.
4894 This has the same purpose as the same-named option in @command{guix
4895 build} (@pxref{Additional Build Options, @code{--expression} in
4896 @command{guix build}}).
4898 @item --manifest=@var{file}
4899 @itemx -m @var{file}
4900 Use the packages contained in the manifest object returned by the Scheme
4903 This has a similar purpose as the same-named option in @command{guix
4904 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
4905 same manifest files. It allows you to define a collection of packages
4906 once and use it both for creating profiles and for creating archives
4907 for use on machines that do not have Guix installed. Note that you can
4908 specify @emph{either} a manifest file @emph{or} a list of packages,
4911 @item --system=@var{system}
4912 @itemx -s @var{system}
4913 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4914 the system type of the build host.
4916 @item --target=@var{triplet}
4917 @cindex cross-compilation
4918 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
4919 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
4920 configuration triplets,, autoconf, Autoconf}).
4922 @item --compression=@var{tool}
4923 @itemx -C @var{tool}
4924 Compress the resulting tarball using @var{tool}---one of @code{gzip},
4925 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
4927 @item --symlink=@var{spec}
4928 @itemx -S @var{spec}
4929 Add the symlinks specified by @var{spec} to the pack. This option can
4930 appear several times.
4932 @var{spec} has the form @code{@var{source}=@var{target}}, where
4933 @var{source} is the symlink that will be created and @var{target} is the
4936 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
4937 symlink pointing to the @file{bin} sub-directory of the profile.
4939 @item --save-provenance
4940 Save provenance information for the packages passed on the command line.
4941 Provenance information includes the URL and commit of the channels in use
4944 Provenance information is saved in the
4945 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
4946 usual package metadata---the name and version of each package, their
4947 propagated inputs, and so on. It is useful information to the recipient of
4948 the pack, who then knows how the pack was (supposedly) obtained.
4950 This option is not enabled by default because, like timestamps, provenance
4951 information contributes nothing to the build process. In other words, there
4952 is an infinity of channel URLs and commit IDs that can lead to the same pack.
4953 Recording such ``silent'' metadata in the output thus potentially breaks the
4954 source-to-binary bitwise reproducibility property.
4956 @item --root=@var{file}
4957 @itemx -r @var{file}
4958 @cindex garbage collector root, for packs
4959 Make @var{file} a symlink to the resulting pack, and register it as a garbage
4962 @item --localstatedir
4963 @itemx --profile-name=@var{name}
4964 Include the ``local state directory'', @file{/var/guix}, in the resulting
4965 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
4966 profile---by default @var{name} is @code{guix-profile}, which corresponds to
4967 @file{~root/.guix-profile}.
4969 @file{/var/guix} contains the store database (@pxref{The Store}) as well
4970 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
4971 the pack means that the store is ``complete'' and manageable by Guix;
4972 not providing it pack means that the store is ``dead'': items cannot be
4973 added to it or removed from it after extraction of the pack.
4975 One use case for this is the Guix self-contained binary tarball
4976 (@pxref{Binary Installation}).
4979 Use the bootstrap binaries to build the pack. This option is only
4980 useful to Guix developers.
4983 In addition, @command{guix pack} supports all the common build options
4984 (@pxref{Common Build Options}) and all the package transformation
4985 options (@pxref{Package Transformation Options}).
4988 @c *********************************************************************
4989 @node Programming Interface
4990 @chapter Programming Interface
4992 GNU Guix provides several Scheme programming interfaces (APIs) to
4993 define, build, and query packages. The first interface allows users to
4994 write high-level package definitions. These definitions refer to
4995 familiar packaging concepts, such as the name and version of a package,
4996 its build system, and its dependencies. These definitions can then be
4997 turned into concrete build actions.
4999 Build actions are performed by the Guix daemon, on behalf of users. In a
5000 standard setup, the daemon has write access to the store---the
5001 @file{/gnu/store} directory---whereas users do not. The recommended
5002 setup also has the daemon perform builds in chroots, under a specific
5003 build users, to minimize interference with the rest of the system.
5006 Lower-level APIs are available to interact with the daemon and the
5007 store. To instruct the daemon to perform a build action, users actually
5008 provide it with a @dfn{derivation}. A derivation is a low-level
5009 representation of the build actions to be taken, and the environment in
5010 which they should occur---derivations are to package definitions what
5011 assembly is to C programs. The term ``derivation'' comes from the fact
5012 that build results @emph{derive} from them.
5014 This chapter describes all these APIs in turn, starting from high-level
5015 package definitions.
5018 * Package Modules:: Packages from the programmer's viewpoint.
5019 * Defining Packages:: Defining new packages.
5020 * Build Systems:: Specifying how packages are built.
5021 * The Store:: Manipulating the package store.
5022 * Derivations:: Low-level interface to package derivations.
5023 * The Store Monad:: Purely functional interface to the store.
5024 * G-Expressions:: Manipulating build expressions.
5025 * Invoking guix repl:: Fiddling with Guix interactively.
5028 @node Package Modules
5029 @section Package Modules
5031 From a programming viewpoint, the package definitions of the
5032 GNU distribution are provided by Guile modules in the @code{(gnu packages
5033 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5034 packages @dots{})} module name space are not necessarily ``GNU
5035 packages''. This module naming scheme follows the usual Guile module
5036 naming convention: @code{gnu} means that these modules are distributed
5037 as part of the GNU system, and @code{packages} identifies modules that
5038 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5039 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5040 module exports a variable named @code{emacs}, which is bound to a
5041 @code{<package>} object (@pxref{Defining Packages}).
5043 The @code{(gnu packages @dots{})} module name space is
5044 automatically scanned for packages by the command-line tools. For
5045 instance, when running @code{guix install emacs}, all the @code{(gnu
5046 packages @dots{})} modules are scanned until one that exports a package
5047 object whose name is @code{emacs} is found. This package search
5048 facility is implemented in the @code{(gnu packages)} module.
5050 @cindex customization, of packages
5051 @cindex package module search path
5052 Users can store package definitions in modules with different
5053 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5054 name and module name must match. For instance, the @code{(my-packages
5055 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5056 relative to the load path specified with @option{--load-path} or
5057 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5058 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5059 these package definitions visible to the user interfaces:
5063 By adding the directory containing your package modules to the search path
5064 with the @code{-L} flag of @command{guix package} and other commands
5065 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5066 environment variable described below.
5069 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5070 pulls from it. A channel is essentially a Git repository containing package
5071 modules. @xref{Channels}, for more information on how to define and use
5075 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5077 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5078 This is a colon-separated list of directories to search for additional
5079 package modules. Directories listed in this variable take precedence
5080 over the own modules of the distribution.
5083 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5084 each package is built based solely on other packages in the
5085 distribution. The root of this dependency graph is a small set of
5086 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5087 bootstrap)} module. For more information on bootstrapping,
5088 @pxref{Bootstrapping}.
5090 @node Defining Packages
5091 @section Defining Packages
5093 The high-level interface to package definitions is implemented in the
5094 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5095 example, the package definition, or @dfn{recipe}, for the GNU Hello
5096 package looks like this:
5099 (define-module (gnu packages hello)
5100 #:use-module (guix packages)
5101 #:use-module (guix download)
5102 #:use-module (guix build-system gnu)
5103 #:use-module (guix licenses)
5104 #:use-module (gnu packages gawk))
5106 (define-public hello
5112 (uri (string-append "mirror://gnu/hello/hello-" version
5116 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5117 (build-system gnu-build-system)
5118 (arguments '(#:configure-flags '("--enable-silent-rules")))
5119 (inputs `(("gawk" ,gawk)))
5120 (synopsis "Hello, GNU world: An example GNU package")
5121 (description "Guess what GNU Hello prints!")
5122 (home-page "https://www.gnu.org/software/hello/")
5127 Without being a Scheme expert, the reader may have guessed the meaning
5128 of the various fields here. This expression binds the variable
5129 @code{hello} to a @code{<package>} object, which is essentially a record
5130 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5131 This package object can be inspected using procedures found in the
5132 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5133 returns---surprise!---@code{"hello"}.
5135 With luck, you may be able to import part or all of the definition of
5136 the package you are interested in from another repository, using the
5137 @code{guix import} command (@pxref{Invoking guix import}).
5139 In the example above, @var{hello} is defined in a module of its own,
5140 @code{(gnu packages hello)}. Technically, this is not strictly
5141 necessary, but it is convenient to do so: all the packages defined in
5142 modules under @code{(gnu packages @dots{})} are automatically known to
5143 the command-line tools (@pxref{Package Modules}).
5145 There are a few points worth noting in the above package definition:
5149 The @code{source} field of the package is an @code{<origin>} object
5150 (@pxref{origin Reference}, for the complete reference).
5151 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5152 meaning that the source is a file to be downloaded over FTP or HTTP.
5154 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5155 the GNU mirrors defined in @code{(guix download)}.
5157 The @code{sha256} field specifies the expected SHA256 hash of the file
5158 being downloaded. It is mandatory, and allows Guix to check the
5159 integrity of the file. The @code{(base32 @dots{})} form introduces the
5160 base32 representation of the hash. You can obtain this information with
5161 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5162 hash} (@pxref{Invoking guix hash}).
5165 When needed, the @code{origin} form can also have a @code{patches} field
5166 listing patches to be applied, and a @code{snippet} field giving a
5167 Scheme expression to modify the source code.
5170 @cindex GNU Build System
5171 The @code{build-system} field specifies the procedure to build the
5172 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5173 represents the familiar GNU Build System, where packages may be
5174 configured, built, and installed with the usual @code{./configure &&
5175 make && make check && make install} command sequence.
5178 The @code{arguments} field specifies options for the build system
5179 (@pxref{Build Systems}). Here it is interpreted by
5180 @var{gnu-build-system} as a request run @file{configure} with the
5181 @code{--enable-silent-rules} flag.
5187 What about these quote (@code{'}) characters? They are Scheme syntax to
5188 introduce a literal list; @code{'} is synonymous with @code{quote}.
5189 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5190 for details. Here the value of the @code{arguments} field is a list of
5191 arguments passed to the build system down the road, as with @code{apply}
5192 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5195 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5196 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5197 @code{#:configure-flags} is a keyword used to pass a keyword argument
5198 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5202 The @code{inputs} field specifies inputs to the build process---i.e.,
5203 build-time or run-time dependencies of the package. Here, we define an
5204 input called @code{"gawk"} whose value is that of the @var{gawk}
5205 variable; @var{gawk} is itself bound to a @code{<package>} object.
5207 @cindex backquote (quasiquote)
5210 @cindex comma (unquote)
5214 @findex unquote-splicing
5215 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5216 us to introduce a literal list in the @code{inputs} field, while
5217 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5218 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5221 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5222 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5223 of ensuring that they are present (@pxref{Build Systems}).
5225 However, any other dependencies need to be specified in the
5226 @code{inputs} field. Any dependency not specified here will simply be
5227 unavailable to the build process, possibly leading to a build failure.
5230 @xref{package Reference}, for a full description of possible fields.
5232 Once a package definition is in place, the
5233 package may actually be built using the @code{guix build} command-line
5234 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5235 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5236 package definition using the @command{guix edit} command
5237 (@pxref{Invoking guix edit}).
5238 @xref{Packaging Guidelines}, for
5239 more information on how to test package definitions, and
5240 @ref{Invoking guix lint}, for information on how to check a definition
5241 for style conformance.
5242 @vindex GUIX_PACKAGE_PATH
5243 Lastly, @pxref{Channels}, for information
5244 on how to extend the distribution by adding your own package definitions
5247 Finally, updating the package definition to a new upstream version
5248 can be partly automated by the @command{guix refresh} command
5249 (@pxref{Invoking guix refresh}).
5251 Behind the scenes, a derivation corresponding to the @code{<package>}
5252 object is first computed by the @code{package-derivation} procedure.
5253 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5254 The build actions it prescribes may then be realized by using the
5255 @code{build-derivations} procedure (@pxref{The Store}).
5257 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5258 Return the @code{<derivation>} object of @var{package} for @var{system}
5259 (@pxref{Derivations}).
5261 @var{package} must be a valid @code{<package>} object, and @var{system}
5262 must be a string denoting the target system type---e.g.,
5263 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5264 must be a connection to the daemon, which operates on the store
5265 (@pxref{The Store}).
5269 @cindex cross-compilation
5270 Similarly, it is possible to compute a derivation that cross-builds a
5271 package for some other system:
5273 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5274 @var{package} @var{target} [@var{system}]
5275 Return the @code{<derivation>} object of @var{package} cross-built from
5276 @var{system} to @var{target}.
5278 @var{target} must be a valid GNU triplet denoting the target hardware
5279 and operating system, such as @code{"mips64el-linux-gnu"}
5280 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5283 @cindex package transformations
5284 @cindex input rewriting
5285 @cindex dependency tree rewriting
5286 Packages can be manipulated in arbitrary ways. An example of a useful
5287 transformation is @dfn{input rewriting}, whereby the dependency tree of
5288 a package is rewritten by replacing specific inputs by others:
5290 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5291 [@var{rewrite-name}]
5292 Return a procedure that, when passed a package, replaces its direct and
5293 indirect dependencies (but not its implicit inputs) according to
5294 @var{replacements}. @var{replacements} is a list of package pairs; the
5295 first element of each pair is the package to replace, and the second one
5298 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5299 the name of a package and returns its new name after rewrite.
5303 Consider this example:
5306 (define libressl-instead-of-openssl
5307 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5309 (package-input-rewriting `((,openssl . ,libressl))))
5311 (define git-with-libressl
5312 (libressl-instead-of-openssl git))
5316 Here we first define a rewriting procedure that replaces @var{openssl}
5317 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5318 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5319 This is exactly what the @option{--with-input} command-line option does
5320 (@pxref{Package Transformation Options, @option{--with-input}}).
5322 The following variant of @code{package-input-rewriting} can match packages to
5323 be replaced by name rather than by identity.
5325 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5326 Return a procedure that, given a package, applies the given @var{replacements} to
5327 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5328 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5329 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5330 replacement for that package.
5333 The example above could be rewritten this way:
5336 (define libressl-instead-of-openssl
5337 ;; Replace all the packages called "openssl" with LibreSSL.
5338 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5341 The key difference here is that, this time, packages are matched by spec and
5342 not by identity. In other words, any package in the graph that is called
5343 @code{openssl} will be replaced.
5345 A more generic procedure to rewrite a package dependency graph is
5346 @code{package-mapping}: it supports arbitrary changes to nodes in the
5349 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5350 Return a procedure that, given a package, applies @var{proc} to all the packages
5351 depended on and returns the resulting package. The procedure stops recursion
5352 when @var{cut?} returns true for a given package.
5356 * package Reference:: The package data type.
5357 * origin Reference:: The origin data type.
5361 @node package Reference
5362 @subsection @code{package} Reference
5364 This section summarizes all the options available in @code{package}
5365 declarations (@pxref{Defining Packages}).
5367 @deftp {Data Type} package
5368 This is the data type representing a package recipe.
5372 The name of the package, as a string.
5374 @item @code{version}
5375 The version of the package, as a string.
5378 An object telling how the source code for the package should be
5379 acquired. Most of the time, this is an @code{origin} object, which
5380 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5381 can also be any other ``file-like'' object such as a @code{local-file},
5382 which denotes a file from the local file system (@pxref{G-Expressions,
5383 @code{local-file}}).
5385 @item @code{build-system}
5386 The build system that should be used to build the package (@pxref{Build
5389 @item @code{arguments} (default: @code{'()})
5390 The arguments that should be passed to the build system. This is a
5391 list, typically containing sequential keyword-value pairs.
5393 @item @code{inputs} (default: @code{'()})
5394 @itemx @code{native-inputs} (default: @code{'()})
5395 @itemx @code{propagated-inputs} (default: @code{'()})
5396 @cindex inputs, of packages
5397 These fields list dependencies of the package. Each one is a list of
5398 tuples, where each tuple has a label for the input (a string) as its
5399 first element, a package, origin, or derivation as its second element,
5400 and optionally the name of the output thereof that should be used, which
5401 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5402 more on package outputs). For example, the list below specifies three
5406 `(("libffi" ,libffi)
5407 ("libunistring" ,libunistring)
5408 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5411 @cindex cross compilation, package dependencies
5412 The distinction between @code{native-inputs} and @code{inputs} is
5413 necessary when considering cross-compilation. When cross-compiling,
5414 dependencies listed in @code{inputs} are built for the @emph{target}
5415 architecture; conversely, dependencies listed in @code{native-inputs}
5416 are built for the architecture of the @emph{build} machine.
5418 @code{native-inputs} is typically used to list tools needed at
5419 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5420 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5421 this area (@pxref{Invoking guix lint}).
5423 @anchor{package-propagated-inputs}
5424 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5425 specified packages will be automatically installed alongside the package
5426 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5427 package}}, for information on how @command{guix package} deals with
5430 For example this is necessary when a C/C++ library needs headers of
5431 another library to compile, or when a pkg-config file refers to another
5432 one @i{via} its @code{Requires} field.
5434 Another example where @code{propagated-inputs} is useful is for languages
5435 that lack a facility to record the run-time search path akin to the
5436 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5437 more. To ensure that libraries written in those languages can find
5438 library code they depend on at run time, run-time dependencies must be
5439 listed in @code{propagated-inputs} rather than @code{inputs}.
5441 @item @code{outputs} (default: @code{'("out")})
5442 The list of output names of the package. @xref{Packages with Multiple
5443 Outputs}, for typical uses of additional outputs.
5445 @item @code{native-search-paths} (default: @code{'()})
5446 @itemx @code{search-paths} (default: @code{'()})
5447 A list of @code{search-path-specification} objects describing
5448 search-path environment variables honored by the package.
5450 @item @code{replacement} (default: @code{#f})
5451 This must be either @code{#f} or a package object that will be used as a
5452 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5455 @item @code{synopsis}
5456 A one-line description of the package.
5458 @item @code{description}
5459 A more elaborate description of the package.
5461 @item @code{license}
5462 @cindex license, of packages
5463 The license of the package; a value from @code{(guix licenses)},
5464 or a list of such values.
5466 @item @code{home-page}
5467 The URL to the home-page of the package, as a string.
5469 @item @code{supported-systems} (default: @var{%supported-systems})
5470 The list of systems supported by the package, as strings of the form
5471 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5473 @item @code{maintainers} (default: @code{'()})
5474 The list of maintainers of the package, as @code{maintainer} objects.
5476 @item @code{location} (default: source location of the @code{package} form)
5477 The source location of the package. It is useful to override this when
5478 inheriting from another package, in which case this field is not
5479 automatically corrected.
5483 @deffn {Scheme Syntax} this-package
5484 When used in the @emph{lexical scope} of a package field definition, this
5485 identifier resolves to the package being defined.
5487 The example below shows how to add a package as a native input of itself when
5495 ;; When cross-compiled, Guile, for example, depends on
5496 ;; a native version of itself. Add it here.
5497 (native-inputs (if (%current-target-system)
5498 `(("self" ,this-package))
5502 It is an error to refer to @code{this-package} outside a package definition.
5505 @node origin Reference
5506 @subsection @code{origin} Reference
5508 This section summarizes all the options available in @code{origin}
5509 declarations (@pxref{Defining Packages}).
5511 @deftp {Data Type} origin
5512 This is the data type representing a source code origin.
5516 An object containing the URI of the source. The object type depends on
5517 the @code{method} (see below). For example, when using the
5518 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5519 values are: a URL represented as a string, or a list thereof.
5522 A procedure that handles the URI.
5527 @item @var{url-fetch} from @code{(guix download)}
5528 download a file from the HTTP, HTTPS, or FTP URL specified in the
5532 @item @var{git-fetch} from @code{(guix git-download)}
5533 clone the Git version control repository, and check out the revision
5534 specified in the @code{uri} field as a @code{git-reference} object; a
5535 @code{git-reference} looks like this:
5539 (url "git://git.debian.org/git/pkg-shadow/shadow")
5540 (commit "v4.1.5.1"))
5545 A bytevector containing the SHA-256 hash of the source. Typically the
5546 @code{base32} form is used here to generate the bytevector from a
5549 You can obtain this information using @code{guix download}
5550 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5553 @item @code{file-name} (default: @code{#f})
5554 The file name under which the source code should be saved. When this is
5555 @code{#f}, a sensible default value will be used in most cases. In case
5556 the source is fetched from a URL, the file name from the URL will be
5557 used. For version control checkouts, it is recommended to provide the
5558 file name explicitly because the default is not very descriptive.
5560 @item @code{patches} (default: @code{'()})
5561 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5562 file-like objects}) pointing to patches to be applied to the source.
5564 This list of patches must be unconditional. In particular, it cannot
5565 depend on the value of @code{%current-system} or
5566 @code{%current-target-system}.
5568 @item @code{snippet} (default: @code{#f})
5569 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5570 in the source directory. This is a convenient way to modify the source,
5571 sometimes more convenient than a patch.
5573 @item @code{patch-flags} (default: @code{'("-p1")})
5574 A list of command-line flags that should be passed to the @code{patch}
5577 @item @code{patch-inputs} (default: @code{#f})
5578 Input packages or derivations to the patching process. When this is
5579 @code{#f}, the usual set of inputs necessary for patching are provided,
5580 such as GNU@tie{}Patch.
5582 @item @code{modules} (default: @code{'()})
5583 A list of Guile modules that should be loaded during the patching
5584 process and while running the code in the @code{snippet} field.
5586 @item @code{patch-guile} (default: @code{#f})
5587 The Guile package that should be used in the patching process. When
5588 this is @code{#f}, a sensible default is used.
5594 @section Build Systems
5596 @cindex build system
5597 Each package definition specifies a @dfn{build system} and arguments for
5598 that build system (@pxref{Defining Packages}). This @code{build-system}
5599 field represents the build procedure of the package, as well as implicit
5600 dependencies of that build procedure.
5602 Build systems are @code{<build-system>} objects. The interface to
5603 create and manipulate them is provided by the @code{(guix build-system)}
5604 module, and actual build systems are exported by specific modules.
5606 @cindex bag (low-level package representation)
5607 Under the hood, build systems first compile package objects to
5608 @dfn{bags}. A @dfn{bag} is like a package, but with less
5609 ornamentation---in other words, a bag is a lower-level representation of
5610 a package, which includes all the inputs of that package, including some
5611 that were implicitly added by the build system. This intermediate
5612 representation is then compiled to a derivation (@pxref{Derivations}).
5614 Build systems accept an optional list of @dfn{arguments}. In package
5615 definitions, these are passed @i{via} the @code{arguments} field
5616 (@pxref{Defining Packages}). They are typically keyword arguments
5617 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5618 Guile Reference Manual}). The value of these arguments is usually
5619 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5620 by the daemon (@pxref{Derivations}).
5622 The main build system is @var{gnu-build-system}, which implements the
5623 standard build procedure for GNU and many other packages. It
5624 is provided by the @code{(guix build-system gnu)} module.
5626 @defvr {Scheme Variable} gnu-build-system
5627 @var{gnu-build-system} represents the GNU Build System, and variants
5628 thereof (@pxref{Configuration, configuration and makefile conventions,,
5629 standards, GNU Coding Standards}).
5631 @cindex build phases
5632 In a nutshell, packages using it are configured, built, and installed with
5633 the usual @code{./configure && make && make check && make install}
5634 command sequence. In practice, a few additional steps are often needed.
5635 All these steps are split up in separate @dfn{phases},
5636 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5637 modules for more details about the build phases.}:
5641 Unpack the source tarball, and change the current directory to the
5642 extracted source tree. If the source is actually a directory, copy it
5643 to the build tree, and enter that directory.
5645 @item patch-source-shebangs
5646 Patch shebangs encountered in source files so they refer to the right
5647 store file names. For instance, this changes @code{#!/bin/sh} to
5648 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
5651 Run the @file{configure} script with a number of default options, such
5652 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
5653 by the @code{#:configure-flags} argument.
5656 Run @code{make} with the list of flags specified with
5657 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
5658 (the default), build with @code{make -j}.
5661 Run @code{make check}, or some other target specified with
5662 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
5663 @code{#:parallel-tests?} argument is true (the default), run @code{make
5667 Run @code{make install} with the flags listed in @code{#:make-flags}.
5669 @item patch-shebangs
5670 Patch shebangs on the installed executable files.
5673 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
5674 is false), copying them to the @code{debug} output when available
5675 (@pxref{Installing Debugging Files}).
5678 @vindex %standard-phases
5679 The build-side module @code{(guix build gnu-build-system)} defines
5680 @var{%standard-phases} as the default list of build phases.
5681 @var{%standard-phases} is a list of symbol/procedure pairs, where the
5682 procedure implements the actual phase.
5684 The list of phases used for a particular package can be changed with the
5685 @code{#:phases} parameter. For instance, passing:
5688 #:phases (modify-phases %standard-phases (delete 'configure))
5691 means that all the phases described above will be used, except the
5692 @code{configure} phase.
5694 In addition, this build system ensures that the ``standard'' environment
5695 for GNU packages is available. This includes tools such as GCC, libc,
5696 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
5697 build-system gnu)} module for a complete list). We call these the
5698 @dfn{implicit inputs} of a package, because package definitions do not
5699 have to mention them.
5702 Other @code{<build-system>} objects are defined to support other
5703 conventions and tools used by free software packages. They inherit most
5704 of @var{gnu-build-system}, and differ mainly in the set of inputs
5705 implicitly added to the build process, and in the list of phases
5706 executed. Some of these build systems are listed below.
5708 @defvr {Scheme Variable} ant-build-system
5709 This variable is exported by @code{(guix build-system ant)}. It
5710 implements the build procedure for Java packages that can be built with
5711 @url{https://ant.apache.org/, Ant build tool}.
5713 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
5714 provided by the @code{icedtea} package to the set of inputs. Different
5715 packages can be specified with the @code{#:ant} and @code{#:jdk}
5716 parameters, respectively.
5718 When the original package does not provide a suitable Ant build file,
5719 the parameter @code{#:jar-name} can be used to generate a minimal Ant
5720 build file @file{build.xml} with tasks to build the specified jar
5721 archive. In this case the parameter @code{#:source-dir} can be used to
5722 specify the source sub-directory, defaulting to ``src''.
5724 The @code{#:main-class} parameter can be used with the minimal ant
5725 buildfile to specify the main class of the resulting jar. This makes the
5726 jar file executable. The @code{#:test-include} parameter can be used to
5727 specify the list of junit tests to run. It defaults to
5728 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
5729 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
5730 because abstract classes cannot be run as tests.
5732 The parameter @code{#:build-target} can be used to specify the Ant task
5733 that should be run during the @code{build} phase. By default the
5734 ``jar'' task will be run.
5738 @defvr {Scheme Variable} android-ndk-build-system
5739 @cindex Android distribution
5740 @cindex Android NDK build system
5741 This variable is exported by @code{(guix build-system android-ndk)}. It
5742 implements a build procedure for Android NDK (native development kit)
5743 packages using a Guix-specific build process.
5745 The build system assumes that packages install their public interface
5746 (header) files to the subdirectory "include" of the "out" output and
5747 their libraries to the subdirectory "lib" of the "out" output.
5749 It's also assumed that the union of all the dependencies of a package
5750 has no conflicting files.
5752 For the time being, cross-compilation is not supported - so right now
5753 the libraries and header files are assumed to be host tools.
5757 @defvr {Scheme Variable} asdf-build-system/source
5758 @defvrx {Scheme Variable} asdf-build-system/sbcl
5759 @defvrx {Scheme Variable} asdf-build-system/ecl
5761 These variables, exported by @code{(guix build-system asdf)}, implement
5762 build procedures for Common Lisp packages using
5763 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
5764 definition facility for Common Lisp programs and libraries.
5766 The @code{asdf-build-system/source} system installs the packages in
5767 source form, and can be loaded using any common lisp implementation, via
5768 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
5769 systems in the format which a particular implementation understands.
5770 These build systems can also be used to produce executable programs, or
5771 lisp images which contain a set of packages pre-loaded.
5773 The build system uses naming conventions. For binary packages, the
5774 package name should be prefixed with the lisp implementation, such as
5775 @code{sbcl-} for @code{asdf-build-system/sbcl}.
5777 Additionally, the corresponding source package should be labeled using
5778 the same convention as python packages (see @ref{Python Modules}), using
5779 the @code{cl-} prefix.
5781 For binary packages, each system should be defined as a Guix package.
5782 If one package @code{origin} contains several systems, package variants
5783 can be created in order to build all the systems. Source packages,
5784 which use @code{asdf-build-system/source}, may contain several systems.
5786 In order to create executable programs and images, the build-side
5787 procedures @code{build-program} and @code{build-image} can be used.
5788 They should be called in a build phase after the @code{create-symlinks}
5789 phase, so that the system which was just built can be used within the
5790 resulting image. @code{build-program} requires a list of Common Lisp
5791 expressions to be passed as the @code{#:entry-program} argument.
5793 If the system is not defined within its own @code{.asd} file of the same
5794 name, then the @code{#:asd-file} parameter should be used to specify
5795 which file the system is defined in. Furthermore, if the package
5796 defines a system for its tests in a separate file, it will be loaded
5797 before the tests are run if it is specified by the
5798 @code{#:test-asd-file} parameter. If it is not set, the files
5799 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
5800 and @code{test.asd} will be tried if they exist.
5802 If for some reason the package must be named in a different way than the
5803 naming conventions suggest, the @code{#:asd-system-name} parameter can
5804 be used to specify the name of the system.
5808 @defvr {Scheme Variable} cargo-build-system
5809 @cindex Rust programming language
5810 @cindex Cargo (Rust build system)
5811 This variable is exported by @code{(guix build-system cargo)}. It
5812 supports builds of packages using Cargo, the build tool of the
5813 @uref{https://www.rust-lang.org, Rust programming language}.
5815 It adds @code{rustc} and @code{cargo} to the set of inputs.
5816 A different Rust package can be specified with the @code{#:rust} parameter.
5818 Regular cargo dependencies should be added to the package definition via the
5819 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
5820 spec can be a package or a source definition. Note that the spec must
5821 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
5822 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
5823 should be added to the package definition via the
5824 @code{#:cargo-development-inputs} parameter.
5826 In its @code{configure} phase, this build system will make any source inputs
5827 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
5828 parameters available to cargo. The @code{install} phase installs any crate
5829 the binaries if they are defined by the crate.
5832 @cindex Clojure (programming language)
5833 @cindex simple Clojure build system
5834 @defvr {Scheme Variable} clojure-build-system
5835 This variable is exported by @code{(guix build-system clojure)}. It implements
5836 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
5837 using plain old @code{compile} in Clojure. Cross-compilation is not supported
5840 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
5841 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
5842 @code{#:zip} parameters, respectively.
5844 A list of source directories, test directories and jar names can be specified
5845 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
5846 parameters, respectively. Compile directory and main class can be specified
5847 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
5848 Other parameters are documented below.
5850 This build system is an extension of @var{ant-build-system}, but with the
5851 following phases changed:
5856 This phase calls @code{compile} in Clojure to compile source files and runs
5857 @command{jar} to create jars from both source files and compiled files
5858 according to the include list and exclude list specified in
5859 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
5860 has priority over the include list. These lists consist of symbols
5861 representing Clojure libraries or the special keyword @code{#:all} representing
5862 all Clojure libraries found under the source directories. The parameter
5863 @code{#:omit-source?} decides if source should be included into the jars.
5866 This phase runs tests according to the include list and exclude list specified
5867 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
5868 meanings are analogous to that of @code{#:aot-include} and
5869 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
5870 stands for all Clojure libraries found under the test directories. The
5871 parameter @code{#:tests?} decides if tests should be run.
5874 This phase installs all jars built previously.
5877 Apart from the above, this build system also contains an additional phase:
5882 This phase installs all top-level files with base name matching
5883 @var{%doc-regex}. A different regex can be specified with the
5884 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
5885 directories specified in @code{#:doc-dirs} are installed as well.
5889 @defvr {Scheme Variable} cmake-build-system
5890 This variable is exported by @code{(guix build-system cmake)}. It
5891 implements the build procedure for packages using the
5892 @url{https://www.cmake.org, CMake build tool}.
5894 It automatically adds the @code{cmake} package to the set of inputs.
5895 Which package is used can be specified with the @code{#:cmake}
5898 The @code{#:configure-flags} parameter is taken as a list of flags
5899 passed to the @command{cmake} command. The @code{#:build-type}
5900 parameter specifies in abstract terms the flags passed to the compiler;
5901 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
5902 debugging information''), which roughly means that code is compiled with
5903 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
5906 @defvr {Scheme Variable} dune-build-system
5907 This variable is exported by @code{(guix build-system dune)}. It
5908 supports builds of packages using @uref{https://dune.build/, Dune}, a build
5909 tool for the OCaml programming language. It is implemented as an extension
5910 of the @code{ocaml-build-system} which is described below. As such, the
5911 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
5914 It automatically adds the @code{dune} package to the set of inputs.
5915 Which package is used can be specified with the @code{#:dune}
5918 There is no @code{configure} phase because dune packages typically don't
5919 need to be configured. The @code{#:build-flags} parameter is taken as a
5920 list of flags passed to the @code{dune} command during the build.
5922 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
5923 command instead of the more recent @code{dune} command while building
5924 a package. Its default value is @code{#f}.
5926 The @code{#:package} parameter can be passed to specify a package name, which
5927 is useful when a package contains multiple packages and you want to build
5928 only one of them. This is equivalent to passing the @code{-p} argument to
5932 @defvr {Scheme Variable} go-build-system
5933 This variable is exported by @code{(guix build-system go)}. It
5934 implements a build procedure for Go packages using the standard
5935 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
5936 Go build mechanisms}.
5938 The user is expected to provide a value for the key @code{#:import-path}
5939 and, in some cases, @code{#:unpack-path}. The
5940 @url{https://golang.org/doc/code.html#ImportPaths, import path}
5941 corresponds to the file system path expected by the package's build
5942 scripts and any referring packages, and provides a unique way to
5943 refer to a Go package. It is typically based on a combination of the
5944 package source code's remote URI and file system hierarchy structure. In
5945 some cases, you will need to unpack the package's source code to a
5946 different directory structure than the one indicated by the import path,
5947 and @code{#:unpack-path} should be used in such cases.
5949 Packages that provide Go libraries should install their source code into
5950 the built output. The key @code{#:install-source?}, which defaults to
5951 @code{#t}, controls whether or not the source code is installed. It can
5952 be set to @code{#f} for packages that only provide executable files.
5955 @defvr {Scheme Variable} glib-or-gtk-build-system
5956 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
5957 is intended for use with packages making use of GLib or GTK+.
5959 This build system adds the following two phases to the ones defined by
5960 @var{gnu-build-system}:
5963 @item glib-or-gtk-wrap
5964 The phase @code{glib-or-gtk-wrap} ensures that programs in
5965 @file{bin/} are able to find GLib ``schemas'' and
5966 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
5967 modules}. This is achieved by wrapping the programs in launch scripts
5968 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
5969 environment variables.
5971 It is possible to exclude specific package outputs from that wrapping
5972 process by listing their names in the
5973 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
5974 when an output is known not to contain any GLib or GTK+ binaries, and
5975 where wrapping would gratuitously add a dependency of that output on
5978 @item glib-or-gtk-compile-schemas
5979 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
5980 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
5981 GSettings schemas} of GLib are compiled. Compilation is performed by the
5982 @command{glib-compile-schemas} program. It is provided by the package
5983 @code{glib:bin} which is automatically imported by the build system.
5984 The @code{glib} package providing @command{glib-compile-schemas} can be
5985 specified with the @code{#:glib} parameter.
5988 Both phases are executed after the @code{install} phase.
5991 @defvr {Scheme Variable} guile-build-system
5992 This build system is for Guile packages that consist exclusively of Scheme
5993 code and that are so lean that they don't even have a makefile, let alone a
5994 @file{configure} script. It compiles Scheme code using @command{guild
5995 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
5996 installs the @file{.scm} and @file{.go} files in the right place. It also
5997 installs documentation.
5999 This build system supports cross-compilation by using the @code{--target}
6000 option of @command{guild compile}.
6002 Packages built with @code{guile-build-system} must provide a Guile package in
6003 their @code{native-inputs} field.
6006 @defvr {Scheme Variable} minify-build-system
6007 This variable is exported by @code{(guix build-system minify)}. It
6008 implements a minification procedure for simple JavaScript packages.
6010 It adds @code{uglify-js} to the set of inputs and uses it to compress
6011 all JavaScript files in the @file{src} directory. A different minifier
6012 package can be specified with the @code{#:uglify-js} parameter, but it
6013 is expected that the package writes the minified code to the standard
6016 When the input JavaScript files are not all located in the @file{src}
6017 directory, the parameter @code{#:javascript-files} can be used to
6018 specify a list of file names to feed to the minifier.
6021 @defvr {Scheme Variable} ocaml-build-system
6022 This variable is exported by @code{(guix build-system ocaml)}. It implements
6023 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6024 of choosing the correct set of commands to run for each package. OCaml
6025 packages can expect many different commands to be run. This build system will
6028 When the package has a @file{setup.ml} file present at the top-level, it will
6029 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6030 @code{ocaml setup.ml -install}. The build system will assume that this file
6031 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6032 care of setting the prefix and enabling tests if they are not disabled. You
6033 can pass configure and build flags with the @code{#:configure-flags} and
6034 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6035 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6036 bypass this system in the build and install phases.
6038 When the package has a @file{configure} file, it is assumed that it is a
6039 hand-made configure script that requires a different argument format than
6040 in the @code{gnu-build-system}. You can add more flags with the
6041 @code{#:configure-flags} key.
6043 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6044 @code{#t}), it will be used and more flags can be passed to the build and
6045 install phases with the @code{#:make-flags} key.
6047 Finally, some packages do not have these files and use a somewhat standard
6048 location for its build system. In that case, the build system will run
6049 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6050 providing the path to the required findlib module. Additional flags can
6051 be passed via the @code{#:build-flags} key. Install is taken care of by
6052 @command{opam-installer}. In this case, the @code{opam} package must
6053 be added to the @code{native-inputs} field of the package definition.
6055 Note that most OCaml packages assume they will be installed in the same
6056 directory as OCaml, which is not what we want in guix. In particular, they
6057 will install @file{.so} files in their module's directory, which is usually
6058 fine because it is in the OCaml compiler directory. In guix though, these
6059 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6060 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6061 @file{.so} libraries should be installed.
6064 @defvr {Scheme Variable} python-build-system
6065 This variable is exported by @code{(guix build-system python)}. It
6066 implements the more or less standard build procedure used by Python
6067 packages, which consists in running @code{python setup.py build} and
6068 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6070 For packages that install stand-alone Python programs under @code{bin/},
6071 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6072 environment variable points to all the Python libraries they depend on.
6074 Which Python package is used to perform the build can be specified with
6075 the @code{#:python} parameter. This is a useful way to force a package
6076 to be built for a specific version of the Python interpreter, which
6077 might be necessary if the package is only compatible with a single
6078 interpreter version.
6080 By default guix calls @code{setup.py} under control of
6081 @code{setuptools}, much like @command{pip} does. Some packages are not
6082 compatible with setuptools (and pip), thus you can disable this by
6083 setting the @code{#:use-setuptools} parameter to @code{#f}.
6086 @defvr {Scheme Variable} perl-build-system
6087 This variable is exported by @code{(guix build-system perl)}. It
6088 implements the standard build procedure for Perl packages, which either
6089 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6090 followed by @code{Build} and @code{Build install}; or in running
6091 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6092 @code{make} and @code{make install}, depending on which of
6093 @code{Build.PL} or @code{Makefile.PL} is present in the package
6094 distribution. Preference is given to the former if both @code{Build.PL}
6095 and @code{Makefile.PL} exist in the package distribution. This
6096 preference can be reversed by specifying @code{#t} for the
6097 @code{#:make-maker?} parameter.
6099 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6100 passes flags specified by the @code{#:make-maker-flags} or
6101 @code{#:module-build-flags} parameter, respectively.
6103 Which Perl package is used can be specified with @code{#:perl}.
6106 @defvr {Scheme Variable} r-build-system
6107 This variable is exported by @code{(guix build-system r)}. It
6108 implements the build procedure used by @uref{https://r-project.org, R}
6109 packages, which essentially is little more than running @code{R CMD
6110 INSTALL --library=/gnu/store/@dots{}} in an environment where
6111 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6112 are run after installation using the R function
6113 @code{tools::testInstalledPackage}.
6116 @defvr {Scheme Variable} rakudo-build-system
6117 This variable is exported by @code{(guix build-system rakudo)}. It
6118 implements the build procedure used by @uref{https://rakudo.org/,
6119 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6120 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6121 installs the binaries, library files and the resources, as well as wrap
6122 the files under the @code{bin/} directory. Tests can be skipped by
6123 passing @code{#f} to the @code{tests?} parameter.
6125 Which rakudo package is used can be specified with @code{rakudo}.
6126 Which perl6-tap-harness package used for the tests can be specified with
6127 @code{#:prove6} or removed by passing @code{#f} to the
6128 @code{with-prove6?} parameter.
6129 Which perl6-zef package used for tests and installing can be specified
6130 with @code{#:zef} or removed by passing @code{#f} to the
6131 @code{with-zef?} parameter.
6134 @defvr {Scheme Variable} texlive-build-system
6135 This variable is exported by @code{(guix build-system texlive)}. It is
6136 used to build TeX packages in batch mode with a specified engine. The
6137 build system sets the @code{TEXINPUTS} variable to find all TeX source
6138 files in the inputs.
6140 By default it runs @code{luatex} on all files ending on @code{ins}. A
6141 different engine and format can be specified with the
6142 @code{#:tex-format} argument. Different build targets can be specified
6143 with the @code{#:build-targets} argument, which expects a list of file
6144 names. The build system adds only @code{texlive-bin} and
6145 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6146 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6147 and @code{#:texlive-latex-base}, respectively.
6149 The @code{#:tex-directory} parameter tells the build system where to
6150 install the built files under the texmf tree.
6153 @defvr {Scheme Variable} ruby-build-system
6154 This variable is exported by @code{(guix build-system ruby)}. It
6155 implements the RubyGems build procedure used by Ruby packages, which
6156 involves running @code{gem build} followed by @code{gem install}.
6158 The @code{source} field of a package that uses this build system
6159 typically references a gem archive, since this is the format that Ruby
6160 developers use when releasing their software. The build system unpacks
6161 the gem archive, potentially patches the source, runs the test suite,
6162 repackages the gem, and installs it. Additionally, directories and
6163 tarballs may be referenced to allow building unreleased gems from Git or
6164 a traditional source release tarball.
6166 Which Ruby package is used can be specified with the @code{#:ruby}
6167 parameter. A list of additional flags to be passed to the @command{gem}
6168 command can be specified with the @code{#:gem-flags} parameter.
6171 @defvr {Scheme Variable} waf-build-system
6172 This variable is exported by @code{(guix build-system waf)}. It
6173 implements a build procedure around the @code{waf} script. The common
6174 phases---@code{configure}, @code{build}, and @code{install}---are
6175 implemented by passing their names as arguments to the @code{waf}
6178 The @code{waf} script is executed by the Python interpreter. Which
6179 Python package is used to run the script can be specified with the
6180 @code{#:python} parameter.
6183 @defvr {Scheme Variable} scons-build-system
6184 This variable is exported by @code{(guix build-system scons)}. It
6185 implements the build procedure used by the SCons software construction
6186 tool. This build system runs @code{scons} to build the package,
6187 @code{scons test} to run tests, and then @code{scons install} to install
6190 Additional flags to be passed to @code{scons} can be specified with the
6191 @code{#:scons-flags} parameter. The version of Python used to run SCons
6192 can be specified by selecting the appropriate SCons package with the
6193 @code{#:scons} parameter.
6196 @defvr {Scheme Variable} haskell-build-system
6197 This variable is exported by @code{(guix build-system haskell)}. It
6198 implements the Cabal build procedure used by Haskell packages, which
6199 involves running @code{runhaskell Setup.hs configure
6200 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6201 Instead of installing the package by running @code{runhaskell Setup.hs
6202 install}, to avoid trying to register libraries in the read-only
6203 compiler store directory, the build system uses @code{runhaskell
6204 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6205 addition, the build system generates the package documentation by
6206 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6207 is passed. Optional Haddock parameters can be passed with the help of
6208 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6209 not found, the build system looks for @code{Setup.lhs} instead.
6211 Which Haskell compiler is used can be specified with the @code{#:haskell}
6212 parameter which defaults to @code{ghc}.
6215 @defvr {Scheme Variable} dub-build-system
6216 This variable is exported by @code{(guix build-system dub)}. It
6217 implements the Dub build procedure used by D packages, which
6218 involves running @code{dub build} and @code{dub run}.
6219 Installation is done by copying the files manually.
6221 Which D compiler is used can be specified with the @code{#:ldc}
6222 parameter which defaults to @code{ldc}.
6225 @defvr {Scheme Variable} emacs-build-system
6226 This variable is exported by @code{(guix build-system emacs)}. It
6227 implements an installation procedure similar to the packaging system
6228 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6230 It first creates the @code{@var{package}-autoloads.el} file, then it
6231 byte compiles all Emacs Lisp files. Differently from the Emacs
6232 packaging system, the Info documentation files are moved to the standard
6233 documentation directory and the @file{dir} file is deleted. Each
6234 package is installed in its own directory under
6235 @file{share/emacs/site-lisp/guix.d}.
6238 @defvr {Scheme Variable} font-build-system
6239 This variable is exported by @code{(guix build-system font)}. It
6240 implements an installation procedure for font packages where upstream
6241 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6242 need to be copied into place. It copies font files to standard
6243 locations in the output directory.
6246 @defvr {Scheme Variable} meson-build-system
6247 This variable is exported by @code{(guix build-system meson)}. It
6248 implements the build procedure for packages that use
6249 @url{https://mesonbuild.com, Meson} as their build system.
6251 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6252 of inputs, and they can be changed with the parameters @code{#:meson}
6253 and @code{#:ninja} if needed. The default Meson is
6254 @code{meson-for-build}, which is special because it doesn't clear the
6255 @code{RUNPATH} of binaries and libraries when they are installed.
6257 This build system is an extension of @var{gnu-build-system}, but with the
6258 following phases changed to some specific for Meson:
6263 The phase runs @code{meson} with the flags specified in
6264 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6265 @code{plain} unless something else is specified in @code{#:build-type}.
6268 The phase runs @code{ninja} to build the package in parallel by default, but
6269 this can be changed with @code{#:parallel-build?}.
6272 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6273 which is @code{"test"} by default.
6276 The phase runs @code{ninja install} and can not be changed.
6279 Apart from that, the build system also adds the following phases:
6284 This phase ensures that all binaries can find the libraries they need.
6285 It searches for required libraries in subdirectories of the package being
6286 built, and adds those to @code{RUNPATH} where needed. It also removes
6287 references to libraries left over from the build phase by
6288 @code{meson-for-build}, such as test dependencies, that aren't actually
6289 required for the program to run.
6291 @item glib-or-gtk-wrap
6292 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6293 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6295 @item glib-or-gtk-compile-schemas
6296 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6297 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6301 @defvr {Scheme Variable} linux-module-build-system
6302 @var{linux-module-build-system} allows building Linux kernel modules.
6304 @cindex build phases
6305 This build system is an extension of @var{gnu-build-system}, but with the
6306 following phases changed:
6311 This phase configures the environment so that the Linux kernel's Makefile
6312 can be used to build the external kernel module.
6315 This phase uses the Linux kernel's Makefile in order to build the external
6319 This phase uses the Linux kernel's Makefile in order to install the external
6323 It is possible and useful to specify the Linux kernel to use for building
6324 the module (in the "arguments" form of a package using the
6325 linux-module-build-system, use the key #:linux to specify it).
6328 Lastly, for packages that do not need anything as sophisticated, a
6329 ``trivial'' build system is provided. It is trivial in the sense that
6330 it provides basically no support: it does not pull any implicit inputs,
6331 and does not have a notion of build phases.
6333 @defvr {Scheme Variable} trivial-build-system
6334 This variable is exported by @code{(guix build-system trivial)}.
6336 This build system requires a @code{#:builder} argument. This argument
6337 must be a Scheme expression that builds the package output(s)---as
6338 with @code{build-expression->derivation} (@pxref{Derivations,
6339 @code{build-expression->derivation}}).
6349 Conceptually, the @dfn{store} is the place where derivations that have
6350 been built successfully are stored---by default, @file{/gnu/store}.
6351 Sub-directories in the store are referred to as @dfn{store items} or
6352 sometimes @dfn{store paths}. The store has an associated database that
6353 contains information such as the store paths referred to by each store
6354 path, and the list of @emph{valid} store items---results of successful
6355 builds. This database resides in @file{@var{localstatedir}/guix/db},
6356 where @var{localstatedir} is the state directory specified @i{via}
6357 @option{--localstatedir} at configure time, usually @file{/var}.
6359 The store is @emph{always} accessed by the daemon on behalf of its clients
6360 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6361 connect to the daemon over a Unix-domain socket, send requests to it,
6362 and read the result---these are remote procedure calls, or RPCs.
6365 Users must @emph{never} modify files under @file{/gnu/store} directly.
6366 This would lead to inconsistencies and break the immutability
6367 assumptions of Guix's functional model (@pxref{Introduction}).
6369 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6370 how to check the integrity of the store and attempt recovery from
6371 accidental modifications.
6374 The @code{(guix store)} module provides procedures to connect to the
6375 daemon, and to perform RPCs. These are described below. By default,
6376 @code{open-connection}, and thus all the @command{guix} commands,
6377 connect to the local daemon or to the URI specified by the
6378 @code{GUIX_DAEMON_SOCKET} environment variable.
6380 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6381 When set, the value of this variable should be a file name or a URI
6382 designating the daemon endpoint. When it is a file name, it denotes a
6383 Unix-domain socket to connect to. In addition to file names, the
6384 supported URI schemes are:
6389 These are for Unix-domain sockets.
6390 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6391 @file{/var/guix/daemon-socket/socket}.
6394 @cindex daemon, remote access
6395 @cindex remote access to the daemon
6396 @cindex daemon, cluster setup
6397 @cindex clusters, daemon setup
6398 These URIs denote connections over TCP/IP, without encryption nor
6399 authentication of the remote host. The URI must specify the host name
6400 and optionally a port number (by default port 44146 is used):
6403 guix://master.guix.example.org:1234
6406 This setup is suitable on local networks, such as clusters, where only
6407 trusted nodes may connect to the build daemon at
6408 @code{master.guix.example.org}.
6410 The @code{--listen} option of @command{guix-daemon} can be used to
6411 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6415 @cindex SSH access to build daemons
6416 These URIs allow you to connect to a remote daemon over
6417 SSH@footnote{This feature requires Guile-SSH (@pxref{Requirements}).}.
6418 A typical URL might look like this:
6421 ssh://charlie@@guix.example.org:22
6424 As for @command{guix copy}, the usual OpenSSH client configuration files
6425 are honored (@pxref{Invoking guix copy}).
6428 Additional URI schemes may be supported in the future.
6430 @c XXX: Remove this note when the protocol incurs fewer round trips
6431 @c and when (guix derivations) no longer relies on file system access.
6433 The ability to connect to remote build daemons is considered
6434 experimental as of @value{VERSION}. Please get in touch with us to
6435 share any problems or suggestions you may have (@pxref{Contributing}).
6439 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6440 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6441 @var{reserve-space?} is true, instruct it to reserve a little bit of
6442 extra space on the file system so that the garbage collector can still
6443 operate should the disk become full. Return a server object.
6445 @var{file} defaults to @code{%default-socket-path}, which is the normal
6446 location given the options that were passed to @command{configure}.
6449 @deffn {Scheme Procedure} close-connection @var{server}
6450 Close the connection to @var{server}.
6453 @defvr {Scheme Variable} current-build-output-port
6454 This variable is bound to a SRFI-39 parameter, which refers to the port
6455 where build and error logs sent by the daemon should be written.
6458 Procedures that make RPCs all take a server object as their first
6461 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6462 @cindex invalid store items
6463 Return @code{#t} when @var{path} designates a valid store item and
6464 @code{#f} otherwise (an invalid item may exist on disk but still be
6465 invalid, for instance because it is the result of an aborted or failed
6468 A @code{&store-protocol-error} condition is raised if @var{path} is not
6469 prefixed by the store directory (@file{/gnu/store}).
6472 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6473 Add @var{text} under file @var{name} in the store, and return its store
6474 path. @var{references} is the list of store paths referred to by the
6475 resulting store path.
6478 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6480 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6481 file names, or derivation/output pairs, using the specified
6482 @var{mode}---@code{(build-mode normal)} by default.
6485 Note that the @code{(guix monads)} module provides a monad as well as
6486 monadic versions of the above procedures, with the goal of making it
6487 more convenient to work with code that accesses the store (@pxref{The
6491 @i{This section is currently incomplete.}
6494 @section Derivations
6497 Low-level build actions and the environment in which they are performed
6498 are represented by @dfn{derivations}. A derivation contains the
6499 following pieces of information:
6503 The outputs of the derivation---derivations produce at least one file or
6504 directory in the store, but may produce more.
6507 @cindex build-time dependencies
6508 @cindex dependencies, build-time
6509 The inputs of the derivations---i.e., its build-time dependencies---which may
6510 be other derivations or plain files in the store (patches, build scripts,
6514 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
6517 The file name of a build script in the store, along with the arguments
6521 A list of environment variables to be defined.
6525 @cindex derivation path
6526 Derivations allow clients of the daemon to communicate build actions to
6527 the store. They exist in two forms: as an in-memory representation,
6528 both on the client- and daemon-side, and as files in the store whose
6529 name end in @code{.drv}---these files are referred to as @dfn{derivation
6530 paths}. Derivations paths can be passed to the @code{build-derivations}
6531 procedure to perform the build actions they prescribe (@pxref{The
6534 @cindex fixed-output derivations
6535 Operations such as file downloads and version-control checkouts for
6536 which the expected content hash is known in advance are modeled as
6537 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
6538 of a fixed-output derivation are independent of its inputs---e.g., a
6539 source code download produces the same result regardless of the download
6540 method and tools being used.
6543 @cindex run-time dependencies
6544 @cindex dependencies, run-time
6545 The outputs of derivations---i.e., the build results---have a set of
6546 @dfn{references}, as reported by the @code{references} RPC or the
6547 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
6548 are the set of run-time dependencies of the build results. References are a
6549 subset of the inputs of the derivation; this subset is automatically computed
6550 by the build daemon by scanning all the files in the outputs.
6552 The @code{(guix derivations)} module provides a representation of
6553 derivations as Scheme objects, along with procedures to create and
6554 otherwise manipulate derivations. The lowest-level primitive to create
6555 a derivation is the @code{derivation} procedure:
6557 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
6558 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6559 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
6560 [#:system (%current-system)] [#:references-graphs #f] @
6561 [#:allowed-references #f] [#:disallowed-references #f] @
6562 [#:leaked-env-vars #f] [#:local-build? #f] @
6563 [#:substitutable? #t] [#:properties '()]
6564 Build a derivation with the given arguments, and return the resulting
6565 @code{<derivation>} object.
6567 When @var{hash} and @var{hash-algo} are given, a
6568 @dfn{fixed-output derivation} is created---i.e., one whose result is
6569 known in advance, such as a file download. If, in addition,
6570 @var{recursive?} is true, then that fixed output may be an executable
6571 file or a directory and @var{hash} must be the hash of an archive
6572 containing this output.
6574 When @var{references-graphs} is true, it must be a list of file
6575 name/store path pairs. In that case, the reference graph of each store
6576 path is exported in the build environment in the corresponding file, in
6577 a simple text format.
6579 When @var{allowed-references} is true, it must be a list of store items
6580 or outputs that the derivation's output may refer to. Likewise,
6581 @var{disallowed-references}, if true, must be a list of things the
6582 outputs may @emph{not} refer to.
6584 When @var{leaked-env-vars} is true, it must be a list of strings
6585 denoting environment variables that are allowed to ``leak'' from the
6586 daemon's environment to the build environment. This is only applicable
6587 to fixed-output derivations---i.e., when @var{hash} is true. The main
6588 use is to allow variables such as @code{http_proxy} to be passed to
6589 derivations that download files.
6591 When @var{local-build?} is true, declare that the derivation is not a
6592 good candidate for offloading and should rather be built locally
6593 (@pxref{Daemon Offload Setup}). This is the case for small derivations
6594 where the costs of data transfers would outweigh the benefits.
6596 When @var{substitutable?} is false, declare that substitutes of the
6597 derivation's output should not be used (@pxref{Substitutes}). This is
6598 useful, for instance, when building packages that capture details of the
6599 host CPU instruction set.
6601 @var{properties} must be an association list describing ``properties'' of the
6602 derivation. It is kept as-is, uninterpreted, in the derivation.
6606 Here's an example with a shell script as its builder, assuming
6607 @var{store} is an open connection to the daemon, and @var{bash} points
6608 to a Bash executable in the store:
6611 (use-modules (guix utils)
6615 (let ((builder ; add the Bash script to the store
6616 (add-text-to-store store "my-builder.sh"
6617 "echo hello world > $out\n" '())))
6618 (derivation store "foo"
6619 bash `("-e" ,builder)
6620 #:inputs `((,bash) (,builder))
6621 #:env-vars '(("HOME" . "/homeless"))))
6622 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
6625 As can be guessed, this primitive is cumbersome to use directly. A
6626 better approach is to write build scripts in Scheme, of course! The
6627 best course of action for that is to write the build code as a
6628 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
6629 information, @pxref{G-Expressions}.
6631 Once upon a time, @code{gexp->derivation} did not exist and constructing
6632 derivations with build code written in Scheme was achieved with
6633 @code{build-expression->derivation}, documented below. This procedure
6634 is now deprecated in favor of the much nicer @code{gexp->derivation}.
6636 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
6637 @var{name} @var{exp} @
6638 [#:system (%current-system)] [#:inputs '()] @
6639 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6640 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
6641 [#:references-graphs #f] [#:allowed-references #f] @
6642 [#:disallowed-references #f] @
6643 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
6644 Return a derivation that executes Scheme expression @var{exp} as a
6645 builder for derivation @var{name}. @var{inputs} must be a list of
6646 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
6647 @code{"out"} is assumed. @var{modules} is a list of names of Guile
6648 modules from the current search path to be copied in the store,
6649 compiled, and made available in the load path during the execution of
6650 @var{exp}---e.g., @code{((guix build utils) (guix build
6651 gnu-build-system))}.
6653 @var{exp} is evaluated in an environment where @code{%outputs} is bound
6654 to a list of output/path pairs, and where @code{%build-inputs} is bound
6655 to a list of string/output-path pairs made from @var{inputs}.
6656 Optionally, @var{env-vars} is a list of string pairs specifying the name
6657 and value of environment variables visible to the builder. The builder
6658 terminates by passing the result of @var{exp} to @code{exit}; thus, when
6659 @var{exp} returns @code{#f}, the build is considered to have failed.
6661 @var{exp} is built using @var{guile-for-build} (a derivation). When
6662 @var{guile-for-build} is omitted or is @code{#f}, the value of the
6663 @code{%guile-for-build} fluid is used instead.
6665 See the @code{derivation} procedure for the meaning of
6666 @var{references-graphs}, @var{allowed-references},
6667 @var{disallowed-references}, @var{local-build?}, and
6668 @var{substitutable?}.
6672 Here's an example of a single-output derivation that creates a directory
6673 containing one file:
6676 (let ((builder '(let ((out (assoc-ref %outputs "out")))
6677 (mkdir out) ; create /gnu/store/@dots{}-goo
6678 (call-with-output-file (string-append out "/test")
6680 (display '(hello guix) p))))))
6681 (build-expression->derivation store "goo" builder))
6683 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
6687 @node The Store Monad
6688 @section The Store Monad
6692 The procedures that operate on the store described in the previous
6693 sections all take an open connection to the build daemon as their first
6694 argument. Although the underlying model is functional, they either have
6695 side effects or depend on the current state of the store.
6697 The former is inconvenient: the connection to the build daemon has to be
6698 carried around in all those functions, making it impossible to compose
6699 functions that do not take that parameter with functions that do. The
6700 latter can be problematic: since store operations have side effects
6701 and/or depend on external state, they have to be properly sequenced.
6703 @cindex monadic values
6704 @cindex monadic functions
6705 This is where the @code{(guix monads)} module comes in. This module
6706 provides a framework for working with @dfn{monads}, and a particularly
6707 useful monad for our uses, the @dfn{store monad}. Monads are a
6708 construct that allows two things: associating ``context'' with values
6709 (in our case, the context is the store), and building sequences of
6710 computations (here computations include accesses to the store). Values
6711 in a monad---values that carry this additional context---are called
6712 @dfn{monadic values}; procedures that return such values are called
6713 @dfn{monadic procedures}.
6715 Consider this ``normal'' procedure:
6718 (define (sh-symlink store)
6719 ;; Return a derivation that symlinks the 'bash' executable.
6720 (let* ((drv (package-derivation store bash))
6721 (out (derivation->output-path drv))
6722 (sh (string-append out "/bin/bash")))
6723 (build-expression->derivation store "sh"
6724 `(symlink ,sh %output))))
6727 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
6728 as a monadic function:
6731 (define (sh-symlink)
6732 ;; Same, but return a monadic value.
6733 (mlet %store-monad ((drv (package->derivation bash)))
6734 (gexp->derivation "sh"
6735 #~(symlink (string-append #$drv "/bin/bash")
6739 There are several things to note in the second version: the @code{store}
6740 parameter is now implicit and is ``threaded'' in the calls to the
6741 @code{package->derivation} and @code{gexp->derivation} monadic
6742 procedures, and the monadic value returned by @code{package->derivation}
6743 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
6745 As it turns out, the call to @code{package->derivation} can even be
6746 omitted since it will take place implicitly, as we will see later
6747 (@pxref{G-Expressions}):
6750 (define (sh-symlink)
6751 (gexp->derivation "sh"
6752 #~(symlink (string-append #$bash "/bin/bash")
6757 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
6758 @c for the funny quote.
6759 Calling the monadic @code{sh-symlink} has no effect. As someone once
6760 said, ``you exit a monad like you exit a building on fire: by running''.
6761 So, to exit the monad and get the desired effect, one must use
6762 @code{run-with-store}:
6765 (run-with-store (open-connection) (sh-symlink))
6766 @result{} /gnu/store/...-sh-symlink
6769 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
6770 new ``meta-commands'' to make it easier to deal with monadic procedures:
6771 @code{run-in-store}, and @code{enter-store-monad}. The former is used
6772 to ``run'' a single monadic value through the store:
6775 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
6776 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6779 The latter enters a recursive REPL, where all the return values are
6780 automatically run through the store:
6783 scheme@@(guile-user)> ,enter-store-monad
6784 store-monad@@(guile-user) [1]> (package->derivation hello)
6785 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6786 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
6787 $3 = "/gnu/store/@dots{}-foo"
6788 store-monad@@(guile-user) [1]> ,q
6789 scheme@@(guile-user)>
6793 Note that non-monadic values cannot be returned in the
6794 @code{store-monad} REPL.
6796 The main syntactic forms to deal with monads in general are provided by
6797 the @code{(guix monads)} module and are described below.
6799 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
6800 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
6804 @deffn {Scheme Syntax} return @var{val}
6805 Return a monadic value that encapsulates @var{val}.
6808 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
6809 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
6810 procedures @var{mproc}@dots{}@footnote{This operation is commonly
6811 referred to as ``bind'', but that name denotes an unrelated procedure in
6812 Guile. Thus we use this somewhat cryptic symbol inherited from the
6813 Haskell language.}. There can be one @var{mproc} or several of them, as
6818 (with-monad %state-monad
6820 (lambda (x) (return (+ 1 x)))
6821 (lambda (x) (return (* 2 x)))))
6825 @result{} some-state
6829 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
6831 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
6833 Bind the variables @var{var} to the monadic values @var{mval} in
6834 @var{body}, which is a sequence of expressions. As with the bind
6835 operator, this can be thought of as ``unpacking'' the raw, non-monadic
6836 value ``contained'' in @var{mval} and making @var{var} refer to that
6837 raw, non-monadic value within the scope of the @var{body}. The form
6838 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
6839 @var{val}, as per @code{let}. The binding operations occur in sequence
6840 from left to right. The last expression of @var{body} must be a monadic
6841 expression, and its result will become the result of the @code{mlet} or
6842 @code{mlet*} when run in the @var{monad}.
6844 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
6845 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
6848 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
6849 Bind @var{mexp} and the following monadic expressions in sequence,
6850 returning the result of the last expression. Every expression in the
6851 sequence must be a monadic expression.
6853 This is akin to @code{mlet}, except that the return values of the
6854 monadic expressions are ignored. In that sense, it is analogous to
6855 @code{begin}, but applied to monadic expressions.
6858 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
6859 When @var{condition} is true, evaluate the sequence of monadic
6860 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6861 @var{condition} is false, return @code{*unspecified*} in the current
6862 monad. Every expression in the sequence must be a monadic expression.
6865 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
6866 When @var{condition} is false, evaluate the sequence of monadic
6867 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6868 @var{condition} is true, return @code{*unspecified*} in the current
6869 monad. Every expression in the sequence must be a monadic expression.
6873 The @code{(guix monads)} module provides the @dfn{state monad}, which
6874 allows an additional value---the state---to be @emph{threaded} through
6875 monadic procedure calls.
6877 @defvr {Scheme Variable} %state-monad
6878 The state monad. Procedures in the state monad can access and change
6879 the state that is threaded.
6881 Consider the example below. The @code{square} procedure returns a value
6882 in the state monad. It returns the square of its argument, but also
6883 increments the current state value:
6887 (mlet %state-monad ((count (current-state)))
6888 (mbegin %state-monad
6889 (set-current-state (+ 1 count))
6892 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
6897 When ``run'' through @var{%state-monad}, we obtain that additional state
6898 value, which is the number of @code{square} calls.
6901 @deffn {Monadic Procedure} current-state
6902 Return the current state as a monadic value.
6905 @deffn {Monadic Procedure} set-current-state @var{value}
6906 Set the current state to @var{value} and return the previous state as a
6910 @deffn {Monadic Procedure} state-push @var{value}
6911 Push @var{value} to the current state, which is assumed to be a list,
6912 and return the previous state as a monadic value.
6915 @deffn {Monadic Procedure} state-pop
6916 Pop a value from the current state and return it as a monadic value.
6917 The state is assumed to be a list.
6920 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
6921 Run monadic value @var{mval} starting with @var{state} as the initial
6922 state. Return two values: the resulting value, and the resulting state.
6925 The main interface to the store monad, provided by the @code{(guix
6926 store)} module, is as follows.
6928 @defvr {Scheme Variable} %store-monad
6929 The store monad---an alias for @var{%state-monad}.
6931 Values in the store monad encapsulate accesses to the store. When its
6932 effect is needed, a value of the store monad must be ``evaluated'' by
6933 passing it to the @code{run-with-store} procedure (see below.)
6936 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
6937 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
6938 open store connection.
6941 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
6942 Return as a monadic value the absolute file name in the store of the file
6943 containing @var{text}, a string. @var{references} is a list of store items that the
6944 resulting text file refers to; it defaults to the empty list.
6947 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
6948 Return as a monadic value the absolute file name in the store of the file
6949 containing @var{data}, a bytevector. @var{references} is a list of store
6950 items that the resulting binary file refers to; it defaults to the empty list.
6953 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
6954 [#:recursive? #t] [#:select? (const #t)]
6955 Return the name of @var{file} once interned in the store. Use
6956 @var{name} as its store name, or the basename of @var{file} if
6957 @var{name} is omitted.
6959 When @var{recursive?} is true, the contents of @var{file} are added
6960 recursively; if @var{file} designates a flat file and @var{recursive?}
6961 is true, its contents are added, and its permission bits are kept.
6963 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
6964 @var{stat})} for each directory entry, where @var{file} is the entry's
6965 absolute file name and @var{stat} is the result of @code{lstat}; exclude
6966 entries for which @var{select?} does not return true.
6968 The example below adds a file to the store, under two different names:
6971 (run-with-store (open-connection)
6972 (mlet %store-monad ((a (interned-file "README"))
6973 (b (interned-file "README" "LEGU-MIN")))
6974 (return (list a b))))
6976 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
6981 The @code{(guix packages)} module exports the following package-related
6984 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
6985 [#:system (%current-system)] [#:target #f] @
6988 value in the absolute file name of @var{file} within the @var{output}
6989 directory of @var{package}. When @var{file} is omitted, return the name
6990 of the @var{output} directory of @var{package}. When @var{target} is
6991 true, use it as a cross-compilation target triplet.
6994 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
6995 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
6996 @var{target} [@var{system}]
6997 Monadic version of @code{package-derivation} and
6998 @code{package-cross-derivation} (@pxref{Defining Packages}).
7003 @section G-Expressions
7005 @cindex G-expression
7006 @cindex build code quoting
7007 So we have ``derivations'', which represent a sequence of build actions
7008 to be performed to produce an item in the store (@pxref{Derivations}).
7009 These build actions are performed when asking the daemon to actually
7010 build the derivations; they are run by the daemon in a container
7011 (@pxref{Invoking guix-daemon}).
7013 @cindex strata of code
7014 It should come as no surprise that we like to write these build actions
7015 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7016 code@footnote{The term @dfn{stratum} in this context was coined by
7017 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7018 Kiselyov, who has written insightful
7019 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7020 on this topic}, refers to this kind of code generation as
7021 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7022 to the daemon, etc.---and the ``build code''---code that actually
7023 performs build actions, such as making directories, invoking
7024 @command{make}, etc.
7026 To describe a derivation and its build actions, one typically needs to
7027 embed build code inside host code. It boils down to manipulating build
7028 code as data, and the homoiconicity of Scheme---code has a direct
7029 representation as data---comes in handy for that. But we need more than
7030 the normal @code{quasiquote} mechanism in Scheme to construct build
7033 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7034 S-expressions adapted to build expressions. G-expressions, or
7035 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7036 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7037 @code{#$}, and @code{#$@@}), which are comparable to
7038 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7039 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7040 GNU Guile Reference Manual}). However, there are major differences:
7044 Gexps are meant to be written to a file and run or manipulated by other
7048 When a high-level object such as a package or derivation is unquoted
7049 inside a gexp, the result is as if its output file name had been
7053 Gexps carry information about the packages or derivations they refer to,
7054 and these dependencies are automatically added as inputs to the build
7055 processes that use them.
7058 @cindex lowering, of high-level objects in gexps
7059 This mechanism is not limited to package and derivation
7060 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7061 derivations or files in the store can be defined,
7062 such that these objects can also be inserted
7063 into gexps. For example, a useful type of high-level objects that can be
7064 inserted in a gexp is ``file-like objects'', which make it easy to
7065 add files to the store and to refer to them in
7066 derivations and such (see @code{local-file} and @code{plain-file}
7069 To illustrate the idea, here is an example of a gexp:
7076 (symlink (string-append #$coreutils "/bin/ls")
7080 This gexp can be passed to @code{gexp->derivation}; we obtain a
7081 derivation that builds a directory containing exactly one symlink to
7082 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7085 (gexp->derivation "the-thing" build-exp)
7088 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7089 substituted to the reference to the @var{coreutils} package in the
7090 actual build code, and @var{coreutils} is automatically made an input to
7091 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7092 output)}) is replaced by a string containing the directory name of the
7093 output of the derivation.
7095 @cindex cross compilation
7096 In a cross-compilation context, it is useful to distinguish between
7097 references to the @emph{native} build of a package---that can run on the
7098 host---versus references to cross builds of a package. To that end, the
7099 @code{#+} plays the same role as @code{#$}, but is a reference to a
7100 native package build:
7103 (gexp->derivation "vi"
7106 (system* (string-append #+coreutils "/bin/ln")
7108 (string-append #$emacs "/bin/emacs")
7109 (string-append #$output "/bin/vi")))
7110 #:target "mips64el-linux-gnu")
7114 In the example above, the native build of @var{coreutils} is used, so
7115 that @command{ln} can actually run on the host; but then the
7116 cross-compiled build of @var{emacs} is referenced.
7118 @cindex imported modules, for gexps
7119 @findex with-imported-modules
7120 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7121 able to use certain Guile modules from the ``host environment'' in the
7122 gexp, so those modules should be imported in the ``build environment''.
7123 The @code{with-imported-modules} form allows you to express that:
7126 (let ((build (with-imported-modules '((guix build utils))
7128 (use-modules (guix build utils))
7129 (mkdir-p (string-append #$output "/bin"))))))
7130 (gexp->derivation "empty-dir"
7133 (display "success!\n")
7138 In this example, the @code{(guix build utils)} module is automatically
7139 pulled into the isolated build environment of our gexp, such that
7140 @code{(use-modules (guix build utils))} works as expected.
7142 @cindex module closure
7143 @findex source-module-closure
7144 Usually you want the @emph{closure} of the module to be imported---i.e.,
7145 the module itself and all the modules it depends on---rather than just
7146 the module; failing to do that, attempts to use the module will fail
7147 because of missing dependent modules. The @code{source-module-closure}
7148 procedure computes the closure of a module by looking at its source file
7149 headers, which comes in handy in this case:
7152 (use-modules (guix modules)) ;for 'source-module-closure'
7154 (with-imported-modules (source-module-closure
7155 '((guix build utils)
7157 (gexp->derivation "something-with-vms"
7159 (use-modules (guix build utils)
7164 @cindex extensions, for gexps
7165 @findex with-extensions
7166 In the same vein, sometimes you want to import not just pure-Scheme
7167 modules, but also ``extensions'' such as Guile bindings to C libraries
7168 or other ``full-blown'' packages. Say you need the @code{guile-json}
7169 package available on the build side, here's how you would do it:
7172 (use-modules (gnu packages guile)) ;for 'guile-json'
7174 (with-extensions (list guile-json)
7175 (gexp->derivation "something-with-json"
7177 (use-modules (json))
7181 The syntactic form to construct gexps is summarized below.
7183 @deffn {Scheme Syntax} #~@var{exp}
7184 @deffnx {Scheme Syntax} (gexp @var{exp})
7185 Return a G-expression containing @var{exp}. @var{exp} may contain one
7186 or more of the following forms:
7190 @itemx (ungexp @var{obj})
7191 Introduce a reference to @var{obj}. @var{obj} may have one of the
7192 supported types, for example a package or a
7193 derivation, in which case the @code{ungexp} form is replaced by its
7194 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7196 If @var{obj} is a list, it is traversed and references to supported
7197 objects are substituted similarly.
7199 If @var{obj} is another gexp, its contents are inserted and its
7200 dependencies are added to those of the containing gexp.
7202 If @var{obj} is another kind of object, it is inserted as is.
7204 @item #$@var{obj}:@var{output}
7205 @itemx (ungexp @var{obj} @var{output})
7206 This is like the form above, but referring explicitly to the
7207 @var{output} of @var{obj}---this is useful when @var{obj} produces
7208 multiple outputs (@pxref{Packages with Multiple Outputs}).
7211 @itemx #+@var{obj}:output
7212 @itemx (ungexp-native @var{obj})
7213 @itemx (ungexp-native @var{obj} @var{output})
7214 Same as @code{ungexp}, but produces a reference to the @emph{native}
7215 build of @var{obj} when used in a cross compilation context.
7217 @item #$output[:@var{output}]
7218 @itemx (ungexp output [@var{output}])
7219 Insert a reference to derivation output @var{output}, or to the main
7220 output when @var{output} is omitted.
7222 This only makes sense for gexps passed to @code{gexp->derivation}.
7225 @itemx (ungexp-splicing @var{lst})
7226 Like the above, but splices the contents of @var{lst} inside the
7230 @itemx (ungexp-native-splicing @var{lst})
7231 Like the above, but refers to native builds of the objects listed in
7236 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7237 of the @code{gexp?} type (see below.)
7240 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7241 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7242 in their execution environment.
7244 Each item in @var{modules} can be the name of a module, such as
7245 @code{(guix build utils)}, or it can be a module name, followed by an
7246 arrow, followed by a file-like object:
7249 `((guix build utils)
7251 ((guix config) => ,(scheme-file "config.scm"
7252 #~(define-module @dots{}))))
7256 In the example above, the first two modules are taken from the search
7257 path, and the last one is created from the given file-like object.
7259 This form has @emph{lexical} scope: it has an effect on the gexps
7260 directly defined in @var{body}@dots{}, but not on those defined, say, in
7261 procedures called from @var{body}@dots{}.
7264 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7265 Mark the gexps defined in @var{body}@dots{} as requiring
7266 @var{extensions} in their build and execution environment.
7267 @var{extensions} is typically a list of package objects such as those
7268 defined in the @code{(gnu packages guile)} module.
7270 Concretely, the packages listed in @var{extensions} are added to the
7271 load path while compiling imported modules in @var{body}@dots{}; they
7272 are also added to the load path of the gexp returned by
7276 @deffn {Scheme Procedure} gexp? @var{obj}
7277 Return @code{#t} if @var{obj} is a G-expression.
7280 G-expressions are meant to be written to disk, either as code building
7281 some derivation, or as plain files in the store. The monadic procedures
7282 below allow you to do that (@pxref{The Store Monad}, for more
7283 information about monads.)
7285 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7286 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7287 [#:hash #f] [#:hash-algo #f] @
7288 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7289 [#:module-path @var{%load-path}] @
7290 [#:effective-version "2.2"] @
7291 [#:references-graphs #f] [#:allowed-references #f] @
7292 [#:disallowed-references #f] @
7293 [#:leaked-env-vars #f] @
7294 [#:script-name (string-append @var{name} "-builder")] @
7295 [#:deprecation-warnings #f] @
7296 [#:local-build? #f] [#:substitutable? #t] @
7297 [#:properties '()] [#:guile-for-build #f]
7298 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7299 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7300 stored in a file called @var{script-name}. When @var{target} is true,
7301 it is used as the cross-compilation target triplet for packages referred
7304 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7306 make @var{modules} available in the evaluation context of @var{exp};
7307 @var{modules} is a list of names of Guile modules searched in
7308 @var{module-path} to be copied in the store, compiled, and made available in
7309 the load path during the execution of @var{exp}---e.g., @code{((guix
7310 build utils) (guix build gnu-build-system))}.
7312 @var{effective-version} determines the string to use when adding extensions of
7313 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7315 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7318 When @var{references-graphs} is true, it must be a list of tuples of one of the
7322 (@var{file-name} @var{package})
7323 (@var{file-name} @var{package} @var{output})
7324 (@var{file-name} @var{derivation})
7325 (@var{file-name} @var{derivation} @var{output})
7326 (@var{file-name} @var{store-item})
7329 The right-hand-side of each element of @var{references-graphs} is automatically made
7330 an input of the build process of @var{exp}. In the build environment, each
7331 @var{file-name} contains the reference graph of the corresponding item, in a simple
7334 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7335 In the latter case, the list denotes store items that the result is allowed to
7336 refer to. Any reference to another store item will lead to a build error.
7337 Similarly for @var{disallowed-references}, which can list items that must not be
7338 referenced by the outputs.
7340 @var{deprecation-warnings} determines whether to show deprecation warnings while
7341 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7343 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7346 @cindex file-like objects
7347 The @code{local-file}, @code{plain-file}, @code{computed-file},
7348 @code{program-file}, and @code{scheme-file} procedures below return
7349 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7350 these objects lead to a file in the store. Consider this G-expression:
7353 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7354 #$(local-file "/tmp/my-nscd.conf"))
7357 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7358 to the store. Once expanded, for instance @i{via}
7359 @code{gexp->derivation}, the G-expression refers to that copy under
7360 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7361 does not have any effect on what the G-expression does.
7362 @code{plain-file} can be used similarly; it differs in that the file
7363 content is directly passed as a string.
7365 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7366 [#:recursive? #f] [#:select? (const #t)]
7367 Return an object representing local file @var{file} to add to the store; this
7368 object can be used in a gexp. If @var{file} is a relative file name, it is looked
7369 up relative to the source file where this form appears. @var{file} will be added to
7370 the store under @var{name}--by default the base name of @var{file}.
7372 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7373 designates a flat file and @var{recursive?} is true, its contents are added, and its
7374 permission bits are kept.
7376 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7377 @var{stat})} for each directory entry, where @var{file} is the entry's
7378 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7379 entries for which @var{select?} does not return true.
7381 This is the declarative counterpart of the @code{interned-file} monadic
7382 procedure (@pxref{The Store Monad, @code{interned-file}}).
7385 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7386 Return an object representing a text file called @var{name} with the given
7387 @var{content} (a string or a bytevector) to be added to the store.
7389 This is the declarative counterpart of @code{text-file}.
7392 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7393 [#:options '(#:local-build? #t)]
7394 Return an object representing the store item @var{name}, a file or
7395 directory computed by @var{gexp}. @var{options}
7396 is a list of additional arguments to pass to @code{gexp->derivation}.
7398 This is the declarative counterpart of @code{gexp->derivation}.
7401 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7402 [#:guile (default-guile)] [#:module-path %load-path]
7403 Return an executable script @var{name} that runs @var{exp} using
7404 @var{guile}, with @var{exp}'s imported modules in its search path.
7405 Look up @var{exp}'s modules in @var{module-path}.
7407 The example below builds a script that simply invokes the @command{ls}
7411 (use-modules (guix gexp) (gnu packages base))
7413 (gexp->script "list-files"
7414 #~(execl #$(file-append coreutils "/bin/ls")
7418 When ``running'' it through the store (@pxref{The Store Monad,
7419 @code{run-with-store}}), we obtain a derivation that produces an
7420 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7423 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7425 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7429 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7430 [#:guile #f] [#:module-path %load-path]
7431 Return an object representing the executable store item @var{name} that
7432 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7433 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7435 This is the declarative counterpart of @code{gexp->script}.
7438 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7439 [#:set-load-path? #t] [#:module-path %load-path] @
7441 [#:guile (default-guile)]
7442 Return a derivation that builds a file @var{name} containing @var{exp}.
7443 When @var{splice?} is true, @var{exp} is considered to be a list of
7444 expressions that will be spliced in the resulting file.
7446 When @var{set-load-path?} is true, emit code in the resulting file to
7447 set @code{%load-path} and @code{%load-compiled-path} to honor
7448 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7451 The resulting file holds references to all the dependencies of @var{exp}
7452 or a subset thereof.
7455 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7456 Return an object representing the Scheme file @var{name} that contains
7459 This is the declarative counterpart of @code{gexp->file}.
7462 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7463 Return as a monadic value a derivation that builds a text file
7464 containing all of @var{text}. @var{text} may list, in addition to
7465 strings, objects of any type that can be used in a gexp: packages,
7466 derivations, local file objects, etc. The resulting store file holds
7467 references to all these.
7469 This variant should be preferred over @code{text-file} anytime the file
7470 to create will reference items from the store. This is typically the
7471 case when building a configuration file that embeds store file names,
7475 (define (profile.sh)
7476 ;; Return the name of a shell script in the store that
7477 ;; initializes the 'PATH' environment variable.
7478 (text-file* "profile.sh"
7479 "export PATH=" coreutils "/bin:"
7480 grep "/bin:" sed "/bin\n"))
7483 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7484 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7485 preventing them from being garbage-collected during its lifetime.
7488 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7489 Return an object representing store file @var{name} containing
7490 @var{text}. @var{text} is a sequence of strings and file-like objects,
7494 (mixed-text-file "profile"
7495 "export PATH=" coreutils "/bin:" grep "/bin")
7498 This is the declarative counterpart of @code{text-file*}.
7501 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7502 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7503 Each item in @var{files} must be a two-element list where the first element is the
7504 file name to use in the new directory, and the second element is a gexp
7505 denoting the target file. Here's an example:
7509 `(("hosts" ,(plain-file "hosts"
7510 "127.0.0.1 localhost"))
7511 ("bashrc" ,(plain-file "bashrc"
7512 "alias ls='ls --color=auto'"))))
7515 This yields an @code{etc} directory containing these two files.
7518 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
7519 Return a directory that is the union of @var{things}, where @var{things} is a list of
7520 file-like objects denoting directories. For example:
7523 (directory-union "guile+emacs" (list guile emacs))
7526 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
7529 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
7530 Return a file-like object that expands to the concatenation of @var{obj}
7531 and @var{suffix}, where @var{obj} is a lowerable object and each
7532 @var{suffix} is a string.
7534 As an example, consider this gexp:
7537 (gexp->script "run-uname"
7538 #~(system* #$(file-append coreutils
7542 The same effect could be achieved with:
7545 (gexp->script "run-uname"
7546 #~(system* (string-append #$coreutils
7550 There is one difference though: in the @code{file-append} case, the
7551 resulting script contains the absolute file name as a string, whereas in
7552 the second case, the resulting script contains a @code{(string-append
7553 @dots{})} expression to construct the file name @emph{at run time}.
7557 Of course, in addition to gexps embedded in ``host'' code, there are
7558 also modules containing build tools. To make it clear that they are
7559 meant to be used in the build stratum, these modules are kept in the
7560 @code{(guix build @dots{})} name space.
7562 @cindex lowering, of high-level objects in gexps
7563 Internally, high-level objects are @dfn{lowered}, using their compiler,
7564 to either derivations or store items. For instance, lowering a package
7565 yields a derivation, and lowering a @code{plain-file} yields a store
7566 item. This is achieved using the @code{lower-object} monadic procedure.
7568 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
7570 Return as a value in @var{%store-monad} the derivation or store item
7571 corresponding to @var{obj} for @var{system}, cross-compiling for
7572 @var{target} if @var{target} is true. @var{obj} must be an object that
7573 has an associated gexp compiler, such as a @code{<package>}.
7576 @node Invoking guix repl
7577 @section Invoking @command{guix repl}
7579 @cindex REPL, read-eval-print loop
7580 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
7581 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
7582 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
7583 command, @command{guix repl} guarantees that all the Guix modules and all its
7584 dependencies are available in the search path. You can use it this way:
7588 scheme@@(guile-user)> ,use (gnu packages base)
7589 scheme@@(guile-user)> coreutils
7590 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
7594 In addition, @command{guix repl} implements a simple machine-readable REPL
7595 protocol for use by @code{(guix inferior)}, a facility to interact with
7596 @dfn{inferiors}, separate processes running a potentially different revision
7599 The available options are as follows:
7602 @item --type=@var{type}
7603 @itemx -t @var{type}
7604 Start a REPL of the given @var{TYPE}, which can be one of the following:
7608 This is default, and it spawns a standard full-featured Guile REPL.
7610 Spawn a REPL that uses the machine-readable protocol. This is the protocol
7611 that the @code{(guix inferior)} module speaks.
7614 @item --listen=@var{endpoint}
7615 By default, @command{guix repl} reads from standard input and writes to
7616 standard output. When this option is passed, it will instead listen for
7617 connections on @var{endpoint}. Here are examples of valid options:
7620 @item --listen=tcp:37146
7621 Accept connections on localhost on port 37146.
7623 @item --listen=unix:/tmp/socket
7624 Accept connections on the Unix-domain socket @file{/tmp/socket}.
7628 @c *********************************************************************
7632 This section describes Guix command-line utilities. Some of them are
7633 primarily targeted at developers and users who write new package
7634 definitions, while others are more generally useful. They complement
7635 the Scheme programming interface of Guix in a convenient way.
7638 * Invoking guix build:: Building packages from the command line.
7639 * Invoking guix edit:: Editing package definitions.
7640 * Invoking guix download:: Downloading a file and printing its hash.
7641 * Invoking guix hash:: Computing the cryptographic hash of a file.
7642 * Invoking guix import:: Importing package definitions.
7643 * Invoking guix refresh:: Updating package definitions.
7644 * Invoking guix lint:: Finding errors in package definitions.
7645 * Invoking guix size:: Profiling disk usage.
7646 * Invoking guix graph:: Visualizing the graph of packages.
7647 * Invoking guix publish:: Sharing substitutes.
7648 * Invoking guix challenge:: Challenging substitute servers.
7649 * Invoking guix copy:: Copying to and from a remote store.
7650 * Invoking guix container:: Process isolation.
7651 * Invoking guix weather:: Assessing substitute availability.
7652 * Invoking guix processes:: Listing client processes.
7655 @node Invoking guix build
7656 @section Invoking @command{guix build}
7658 @cindex package building
7659 @cindex @command{guix build}
7660 The @command{guix build} command builds packages or derivations and
7661 their dependencies, and prints the resulting store paths. Note that it
7662 does not modify the user's profile---this is the job of the
7663 @command{guix package} command (@pxref{Invoking guix package}). Thus,
7664 it is mainly useful for distribution developers.
7666 The general syntax is:
7669 guix build @var{options} @var{package-or-derivation}@dots{}
7672 As an example, the following command builds the latest versions of Emacs
7673 and of Guile, displays their build logs, and finally displays the
7674 resulting directories:
7677 guix build emacs guile
7680 Similarly, the following command builds all the available packages:
7683 guix build --quiet --keep-going \
7684 `guix package -A | cut -f1,2 --output-delimiter=@@`
7687 @var{package-or-derivation} may be either the name of a package found in
7688 the software distribution such as @code{coreutils} or
7689 @code{coreutils@@8.20}, or a derivation such as
7690 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
7691 package with the corresponding name (and optionally version) is searched
7692 for among the GNU distribution modules (@pxref{Package Modules}).
7694 Alternatively, the @code{--expression} option may be used to specify a
7695 Scheme expression that evaluates to a package; this is useful when
7696 disambiguating among several same-named packages or package variants is
7699 There may be zero or more @var{options}. The available options are
7700 described in the subsections below.
7703 * Common Build Options:: Build options for most commands.
7704 * Package Transformation Options:: Creating variants of packages.
7705 * Additional Build Options:: Options specific to 'guix build'.
7706 * Debugging Build Failures:: Real life packaging experience.
7709 @node Common Build Options
7710 @subsection Common Build Options
7712 A number of options that control the build process are common to
7713 @command{guix build} and other commands that can spawn builds, such as
7714 @command{guix package} or @command{guix archive}. These are the
7719 @item --load-path=@var{directory}
7720 @itemx -L @var{directory}
7721 Add @var{directory} to the front of the package module search path
7722 (@pxref{Package Modules}).
7724 This allows users to define their own packages and make them visible to
7725 the command-line tools.
7729 Keep the build tree of failed builds. Thus, if a build fails, its build
7730 tree is kept under @file{/tmp}, in a directory whose name is shown at
7731 the end of the build log. This is useful when debugging build issues.
7732 @xref{Debugging Build Failures}, for tips and tricks on how to debug
7735 This option has no effect when connecting to a remote daemon with a
7736 @code{guix://} URI (@pxref{The Store, the @code{GUIX_DAEMON_SOCKET}
7741 Keep going when some of the derivations fail to build; return only once
7742 all the builds have either completed or failed.
7744 The default behavior is to stop as soon as one of the specified
7745 derivations has failed.
7749 Do not build the derivations.
7751 @anchor{fallback-option}
7753 When substituting a pre-built binary fails, fall back to building
7754 packages locally (@pxref{Substitution Failure}).
7756 @item --substitute-urls=@var{urls}
7757 @anchor{client-substitute-urls}
7758 Consider @var{urls} the whitespace-separated list of substitute source
7759 URLs, overriding the default list of URLs of @command{guix-daemon}
7760 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
7762 This means that substitutes may be downloaded from @var{urls}, provided
7763 they are signed by a key authorized by the system administrator
7764 (@pxref{Substitutes}).
7766 When @var{urls} is the empty string, substitutes are effectively
7769 @item --no-substitutes
7770 Do not use substitutes for build products. That is, always build things
7771 locally instead of allowing downloads of pre-built binaries
7772 (@pxref{Substitutes}).
7775 Do not ``graft'' packages. In practice, this means that package updates
7776 available as grafts are not applied. @xref{Security Updates}, for more
7777 information on grafts.
7779 @item --rounds=@var{n}
7780 Build each derivation @var{n} times in a row, and raise an error if
7781 consecutive build results are not bit-for-bit identical.
7783 This is a useful way to detect non-deterministic builds processes.
7784 Non-deterministic build processes are a problem because they make it
7785 practically impossible for users to @emph{verify} whether third-party
7786 binaries are genuine. @xref{Invoking guix challenge}, for more.
7788 Note that, currently, the differing build results are not kept around,
7789 so you will have to manually investigate in case of an error---e.g., by
7790 stashing one of the build results with @code{guix archive --export}
7791 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
7794 @item --no-build-hook
7795 Do not attempt to offload builds @i{via} the ``build hook'' of the daemon
7796 (@pxref{Daemon Offload Setup}). That is, always build things locally
7797 instead of offloading builds to remote machines.
7799 @item --max-silent-time=@var{seconds}
7800 When the build or substitution process remains silent for more than
7801 @var{seconds}, terminate it and report a build failure.
7803 By default, the daemon's setting is honored (@pxref{Invoking
7804 guix-daemon, @code{--max-silent-time}}).
7806 @item --timeout=@var{seconds}
7807 Likewise, when the build or substitution process lasts for more than
7808 @var{seconds}, terminate it and report a build failure.
7810 By default, the daemon's setting is honored (@pxref{Invoking
7811 guix-daemon, @code{--timeout}}).
7813 @c Note: This option is actually not part of %standard-build-options but
7814 @c most programs honor it.
7815 @cindex verbosity, of the command-line tools
7816 @cindex build logs, verbosity
7817 @item -v @var{level}
7818 @itemx --verbosity=@var{level}
7819 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
7820 output is produced, 1 is for quiet output, and 2 shows all the build log
7821 output on standard error.
7823 @item --cores=@var{n}
7825 Allow the use of up to @var{n} CPU cores for the build. The special
7826 value @code{0} means to use as many CPU cores as available.
7828 @item --max-jobs=@var{n}
7830 Allow at most @var{n} build jobs in parallel. @xref{Invoking
7831 guix-daemon, @code{--max-jobs}}, for details about this option and the
7832 equivalent @command{guix-daemon} option.
7834 @item --debug=@var{level}
7835 Produce debugging output coming from the build daemon. @var{level} must be an
7836 integer between 0 and 5; higher means more verbose output. Setting a level of
7837 4 or more may be helpful when debugging setup issues with the build daemon.
7841 Behind the scenes, @command{guix build} is essentially an interface to
7842 the @code{package-derivation} procedure of the @code{(guix packages)}
7843 module, and to the @code{build-derivations} procedure of the @code{(guix
7844 derivations)} module.
7846 In addition to options explicitly passed on the command line,
7847 @command{guix build} and other @command{guix} commands that support
7848 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
7850 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
7851 Users can define this variable to a list of command line options that
7852 will automatically be used by @command{guix build} and other
7853 @command{guix} commands that can perform builds, as in the example
7857 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
7860 These options are parsed independently, and the result is appended to
7861 the parsed command-line options.
7865 @node Package Transformation Options
7866 @subsection Package Transformation Options
7868 @cindex package variants
7869 Another set of command-line options supported by @command{guix build}
7870 and also @command{guix package} are @dfn{package transformation
7871 options}. These are options that make it possible to define @dfn{package
7872 variants}---for instance, packages built from different source code.
7873 This is a convenient way to create customized packages on the fly
7874 without having to type in the definitions of package variants
7875 (@pxref{Defining Packages}).
7879 @item --with-source=@var{source}
7880 @itemx --with-source=@var{package}=@var{source}
7881 @itemx --with-source=@var{package}@@@var{version}=@var{source}
7882 Use @var{source} as the source of @var{package}, and @var{version} as
7884 @var{source} must be a file name or a URL, as for @command{guix
7885 download} (@pxref{Invoking guix download}).
7887 When @var{package} is omitted,
7888 it is taken to be the package name specified on the
7889 command line that matches the base of @var{source}---e.g.,
7890 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
7891 package is @code{guile}.
7893 Likewise, when @var{version} is omitted, the version string is inferred from
7894 @var{source}; in the previous example, it is @code{2.0.10}.
7896 This option allows users to try out versions of packages other than the
7897 one provided by the distribution. The example below downloads
7898 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
7899 the @code{ed} package:
7902 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
7905 As a developer, @code{--with-source} makes it easy to test release
7909 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
7912 @dots{} or to build from a checkout in a pristine environment:
7915 $ git clone git://git.sv.gnu.org/guix.git
7916 $ guix build guix --with-source=guix@@1.0=./guix
7919 @item --with-input=@var{package}=@var{replacement}
7920 Replace dependency on @var{package} by a dependency on
7921 @var{replacement}. @var{package} must be a package name, and
7922 @var{replacement} must be a package specification such as @code{guile}
7923 or @code{guile@@1.8}.
7925 For instance, the following command builds Guix, but replaces its
7926 dependency on the current stable version of Guile with a dependency on
7927 the legacy version of Guile, @code{guile@@2.0}:
7930 guix build --with-input=guile=guile@@2.0 guix
7933 This is a recursive, deep replacement. So in this example, both
7934 @code{guix} and its dependency @code{guile-json} (which also depends on
7935 @code{guile}) get rebuilt against @code{guile@@2.0}.
7937 This is implemented using the @code{package-input-rewriting} Scheme
7938 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
7940 @item --with-graft=@var{package}=@var{replacement}
7941 This is similar to @code{--with-input} but with an important difference:
7942 instead of rebuilding the whole dependency chain, @var{replacement} is
7943 built and then @dfn{grafted} onto the binaries that were initially
7944 referring to @var{package}. @xref{Security Updates}, for more
7945 information on grafts.
7947 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
7948 and all its dependencies, replacing references to the version of GnuTLS
7949 they currently refer to:
7952 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
7955 This has the advantage of being much faster than rebuilding everything.
7956 But there is a caveat: it works if and only if @var{package} and
7957 @var{replacement} are strictly compatible---for example, if they provide
7958 a library, the application binary interface (ABI) of those libraries
7959 must be compatible. If @var{replacement} is somehow incompatible with
7960 @var{package}, then the resulting package may be unusable. Use with
7963 @item --with-git-url=@var{package}=@var{url}
7964 @cindex Git, using the latest commit
7965 @cindex latest commit, building
7966 Build @var{package} from the latest commit of the @code{master} branch of the
7967 Git repository at @var{url}. Git sub-modules of the repository are fetched,
7970 For example, the following command builds the NumPy Python library against the
7971 latest commit of the master branch of Python itself:
7974 guix build python-numpy \
7975 --with-git-url=python=https://github.com/python/cpython
7978 This option can also be combined with @code{--with-branch} or
7979 @code{--with-commit} (see below).
7981 @cindex continuous integration
7982 Obviously, since it uses the latest commit of the given branch, the result of
7983 such a command varies over time. Nevertheless it is a convenient way to
7984 rebuild entire software stacks against the latest commit of one or more
7985 packages. This is particularly useful in the context of continuous
7988 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
7989 consecutive accesses to the same repository. You may want to clean it up once
7990 in a while to save disk space.
7992 @item --with-branch=@var{package}=@var{branch}
7993 Build @var{package} from the latest commit of @var{branch}. If the
7994 @code{source} field of @var{package} is an origin with the @code{git-fetch}
7995 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
7996 repository URL is taken from that @code{source}. Otherwise you have to use
7997 @code{--with-git-url} to specify the URL of the Git repository.
7999 For instance, the following command builds @code{guile-sqlite3} from the
8000 latest commit of its @code{master} branch, and then builds @code{guix} (which
8001 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8002 specific @code{guile-sqlite3} build:
8005 guix build --with-branch=guile-sqlite3=master cuirass
8008 @item --with-commit=@var{package}=@var{commit}
8009 This is similar to @code{--with-branch}, except that it builds from
8010 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8011 Git commit SHA1 identifier.
8014 @node Additional Build Options
8015 @subsection Additional Build Options
8017 The command-line options presented below are specific to @command{guix
8024 Build quietly, without displaying the build log; this is equivalent to
8025 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8026 (or similar) and can always be retrieved using the @option{--log-file} option.
8028 @item --file=@var{file}
8029 @itemx -f @var{file}
8030 Build the package, derivation, or other file-like object that the code within
8031 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8033 As an example, @var{file} might contain a package definition like this
8034 (@pxref{Defining Packages}):
8037 @verbatiminclude package-hello.scm
8040 @item --expression=@var{expr}
8041 @itemx -e @var{expr}
8042 Build the package or derivation @var{expr} evaluates to.
8044 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8045 guile-1.8)}, which unambiguously designates this specific variant of
8046 version 1.8 of Guile.
8048 Alternatively, @var{expr} may be a G-expression, in which case it is used
8049 as a build program passed to @code{gexp->derivation}
8050 (@pxref{G-Expressions}).
8052 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8053 (@pxref{The Store Monad}). The procedure must return a derivation as a
8054 monadic value, which is then passed through @code{run-with-store}.
8058 Build the source derivations of the packages, rather than the packages
8061 For instance, @code{guix build -S gcc} returns something like
8062 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8065 The returned source tarball is the result of applying any patches and
8066 code snippets specified in the package @code{origin} (@pxref{Defining
8070 Fetch and return the source of @var{package-or-derivation} and all their
8071 dependencies, recursively. This is a handy way to obtain a local copy
8072 of all the source code needed to build @var{packages}, allowing you to
8073 eventually build them even without network access. It is an extension
8074 of the @code{--source} option and can accept one of the following
8075 optional argument values:
8079 This value causes the @code{--sources} option to behave in the same way
8080 as the @code{--source} option.
8083 Build the source derivations of all packages, including any source that
8084 might be listed as @code{inputs}. This is the default value.
8087 $ guix build --sources tzdata
8088 The following derivations will be built:
8089 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8090 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8094 Build the source derivations of all packages, as well of all transitive
8095 inputs to the packages. This can be used e.g.@: to
8096 prefetch package source for later offline building.
8099 $ guix build --sources=transitive tzdata
8100 The following derivations will be built:
8101 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8102 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8103 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8104 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8105 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8106 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8112 @item --system=@var{system}
8113 @itemx -s @var{system}
8114 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8115 the system type of the build host. The @command{guix build} command allows
8116 you to repeat this option several times, in which case it builds for all the
8117 specified systems; other commands ignore extraneous @option{-s} options.
8120 The @code{--system} flag is for @emph{native} compilation and must not
8121 be confused with cross-compilation. See @code{--target} below for
8122 information on cross-compilation.
8125 An example use of this is on Linux-based systems, which can emulate
8126 different personalities. For instance, passing
8127 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8128 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8129 to build packages in a complete 32-bit environment.
8132 Building for an @code{armhf-linux} system is unconditionally enabled on
8133 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8134 allow for this functionality, notably the ThunderX.
8137 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8138 is enabled (@pxref{Virtualization Services,
8139 @code{qemu-binfmt-service-type}}), you can build for any system for
8140 which a QEMU @code{binfmt_misc} handler is installed.
8142 Builds for a system other than that of the machine you are using can
8143 also be offloaded to a remote machine of the right architecture.
8144 @xref{Daemon Offload Setup}, for more information on offloading.
8146 @item --target=@var{triplet}
8147 @cindex cross-compilation
8148 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8149 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8150 configuration triplets,, autoconf, Autoconf}).
8152 @anchor{build-check}
8154 @cindex determinism, checking
8155 @cindex reproducibility, checking
8156 Rebuild @var{package-or-derivation}, which are already available in the
8157 store, and raise an error if the build results are not bit-for-bit
8160 This mechanism allows you to check whether previously installed
8161 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8162 of a package is deterministic. @xref{Invoking guix challenge}, for more
8163 background information and tools.
8165 When used in conjunction with @option{--keep-failed}, the differing
8166 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8167 This makes it easy to look for differences between the two results.
8170 @cindex repairing store items
8171 @cindex corruption, recovering from
8172 Attempt to repair the specified store items, if they are corrupt, by
8173 re-downloading or rebuilding them.
8175 This operation is not atomic and thus restricted to @code{root}.
8179 Return the derivation paths, not the output paths, of the given
8182 @item --root=@var{file}
8183 @itemx -r @var{file}
8184 @cindex GC roots, adding
8185 @cindex garbage collector roots, adding
8186 Make @var{file} a symlink to the result, and register it as a garbage
8189 Consequently, the results of this @command{guix build} invocation are
8190 protected from garbage collection until @var{file} is removed. When
8191 that option is omitted, build results are eligible for garbage
8192 collection as soon as the build completes. @xref{Invoking guix gc}, for
8196 @cindex build logs, access
8197 Return the build log file names or URLs for the given
8198 @var{package-or-derivation}, or raise an error if build logs are
8201 This works regardless of how packages or derivations are specified. For
8202 instance, the following invocations are equivalent:
8205 guix build --log-file `guix build -d guile`
8206 guix build --log-file `guix build guile`
8207 guix build --log-file guile
8208 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8211 If a log is unavailable locally, and unless @code{--no-substitutes} is
8212 passed, the command looks for a corresponding log on one of the
8213 substitute servers (as specified with @code{--substitute-urls}.)
8215 So for instance, imagine you want to see the build log of GDB on MIPS,
8216 but you are actually on an @code{x86_64} machine:
8219 $ guix build --log-file gdb -s mips64el-linux
8220 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8223 You can freely access a huge library of build logs!
8226 @node Debugging Build Failures
8227 @subsection Debugging Build Failures
8229 @cindex build failures, debugging
8230 When defining a new package (@pxref{Defining Packages}), you will
8231 probably find yourself spending some time debugging and tweaking the
8232 build until it succeeds. To do that, you need to operate the build
8233 commands yourself in an environment as close as possible to the one the
8236 To that end, the first thing to do is to use the @option{--keep-failed}
8237 or @option{-K} option of @command{guix build}, which will keep the
8238 failed build tree in @file{/tmp} or whatever directory you specified as
8239 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8241 From there on, you can @command{cd} to the failed build tree and source
8242 the @file{environment-variables} file, which contains all the
8243 environment variable definitions that were in place when the build
8244 failed. So let's say you're debugging a build failure in package
8245 @code{foo}; a typical session would look like this:
8249 @dots{} @i{build fails}
8250 $ cd /tmp/guix-build-foo.drv-0
8251 $ source ./environment-variables
8255 Now, you can invoke commands as if you were the daemon (almost) and
8256 troubleshoot your build process.
8258 Sometimes it happens that, for example, a package's tests pass when you
8259 run them manually but they fail when the daemon runs them. This can
8260 happen because the daemon runs builds in containers where, unlike in our
8261 environment above, network access is missing, @file{/bin/sh} does not
8262 exist, etc. (@pxref{Build Environment Setup}).
8264 In such cases, you may need to run inspect the build process from within
8265 a container similar to the one the build daemon creates:
8270 $ cd /tmp/guix-build-foo.drv-0
8271 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8272 [env]# source ./environment-variables
8276 Here, @command{guix environment -C} creates a container and spawns a new
8277 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8278 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8279 the container, which would may find handy while debugging. The
8280 @option{--no-grafts} option makes sure we get the exact same
8281 environment, with ungrafted packages (@pxref{Security Updates}, for more
8284 To get closer to a container like that used by the build daemon, we can
8285 remove @file{/bin/sh}:
8291 (Don't worry, this is harmless: this is all happening in the throw-away
8292 container created by @command{guix environment}.)
8294 The @command{strace} command is probably not in the search path, but we
8298 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8301 In this way, not only you will have reproduced the environment variables
8302 the daemon uses, you will also be running the build process in a container
8303 similar to the one the daemon uses.
8306 @node Invoking guix edit
8307 @section Invoking @command{guix edit}
8309 @cindex @command{guix edit}
8310 @cindex package definition, editing
8311 So many packages, so many source files! The @command{guix edit} command
8312 facilitates the life of users and packagers by pointing their editor at
8313 the source file containing the definition of the specified packages.
8317 guix edit gcc@@4.9 vim
8321 launches the program specified in the @code{VISUAL} or in the
8322 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8325 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8326 have created your own packages on @code{GUIX_PACKAGE_PATH}
8327 (@pxref{Package Modules}), you will be able to edit the package
8328 recipes. In other cases, you will be able to examine the read-only recipes
8329 for packages currently in the store.
8332 @node Invoking guix download
8333 @section Invoking @command{guix download}
8335 @cindex @command{guix download}
8336 @cindex downloading package sources
8337 When writing a package definition, developers typically need to download
8338 a source tarball, compute its SHA256 hash, and write that
8339 hash in the package definition (@pxref{Defining Packages}). The
8340 @command{guix download} tool helps with this task: it downloads a file
8341 from the given URI, adds it to the store, and prints both its file name
8342 in the store and its SHA256 hash.
8344 The fact that the downloaded file is added to the store saves bandwidth:
8345 when the developer eventually tries to build the newly defined package
8346 with @command{guix build}, the source tarball will not have to be
8347 downloaded again because it is already in the store. It is also a
8348 convenient way to temporarily stash files, which may be deleted
8349 eventually (@pxref{Invoking guix gc}).
8351 The @command{guix download} command supports the same URIs as used in
8352 package definitions. In particular, it supports @code{mirror://} URIs.
8353 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8354 Guile bindings for GnuTLS are available in the user's environment; when
8355 they are not available, an error is raised. @xref{Guile Preparations,
8356 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8357 GnuTLS-Guile}, for more information.
8359 @command{guix download} verifies HTTPS server certificates by loading
8360 the certificates of X.509 authorities from the directory pointed to by
8361 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8362 Certificates}), unless @option{--no-check-certificate} is used.
8364 The following options are available:
8367 @item --format=@var{fmt}
8369 Write the hash in the format specified by @var{fmt}. For more
8370 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8372 @item --no-check-certificate
8373 Do not validate the X.509 certificates of HTTPS servers.
8375 When using this option, you have @emph{absolutely no guarantee} that you
8376 are communicating with the authentic server responsible for the given
8377 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8379 @item --output=@var{file}
8380 @itemx -o @var{file}
8381 Save the downloaded file to @var{file} instead of adding it to the
8385 @node Invoking guix hash
8386 @section Invoking @command{guix hash}
8388 @cindex @command{guix hash}
8389 The @command{guix hash} command computes the SHA256 hash of a file.
8390 It is primarily a convenience tool for anyone contributing to the
8391 distribution: it computes the cryptographic hash of a file, which can be
8392 used in the definition of a package (@pxref{Defining Packages}).
8394 The general syntax is:
8397 guix hash @var{option} @var{file}
8400 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8401 hash of data read from standard input. @command{guix hash} has the
8406 @item --format=@var{fmt}
8408 Write the hash in the format specified by @var{fmt}.
8410 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8411 (@code{hex} and @code{hexadecimal} can be used as well).
8413 If the @option{--format} option is not specified, @command{guix hash}
8414 will output the hash in @code{nix-base32}. This representation is used
8415 in the definitions of packages.
8419 Compute the hash on @var{file} recursively.
8421 In this case, the hash is computed on an archive containing @var{file},
8422 including its children if it is a directory. Some of the metadata of
8423 @var{file} is part of the archive; for instance, when @var{file} is a
8424 regular file, the hash is different depending on whether @var{file} is
8425 executable or not. Metadata such as time stamps has no impact on the
8426 hash (@pxref{Invoking guix archive}).
8427 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8432 When combined with @option{--recursive}, exclude version control system
8433 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8436 As an example, here is how you would compute the hash of a Git checkout,
8437 which is useful when using the @code{git-fetch} method (@pxref{origin
8441 $ git clone http://example.org/foo.git
8447 @node Invoking guix import
8448 @section Invoking @command{guix import}
8450 @cindex importing packages
8451 @cindex package import
8452 @cindex package conversion
8453 @cindex Invoking @command{guix import}
8454 The @command{guix import} command is useful for people who would like to
8455 add a package to the distribution with as little work as
8456 possible---a legitimate demand. The command knows of a few
8457 repositories from which it can ``import'' package metadata. The result
8458 is a package definition, or a template thereof, in the format we know
8459 (@pxref{Defining Packages}).
8461 The general syntax is:
8464 guix import @var{importer} @var{options}@dots{}
8467 @var{importer} specifies the source from which to import package
8468 metadata, and @var{options} specifies a package identifier and other
8469 options specific to @var{importer}. Currently, the available
8474 Import metadata for the given GNU package. This provides a template
8475 for the latest version of that GNU package, including the hash of its
8476 source tarball, and its canonical synopsis and description.
8478 Additional information such as the package dependencies and its
8479 license needs to be figured out manually.
8481 For example, the following command returns a package definition for
8485 guix import gnu hello
8488 Specific command-line options are:
8491 @item --key-download=@var{policy}
8492 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
8493 keys when verifying the package signature. @xref{Invoking guix
8494 refresh, @code{--key-download}}.
8499 Import metadata from the @uref{https://pypi.python.org/, Python Package
8500 Index}. Information is taken from the JSON-formatted description
8501 available at @code{pypi.python.org} and usually includes all the relevant
8502 information, including package dependencies. For maximum efficiency, it
8503 is recommended to install the @command{unzip} utility, so that the
8504 importer can unzip Python wheels and gather data from them.
8506 The command below imports metadata for the @code{itsdangerous} Python
8510 guix import pypi itsdangerous
8516 Traverse the dependency graph of the given upstream package recursively
8517 and generate package expressions for all those packages that are not yet
8523 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
8524 is taken from the JSON-formatted description available at
8525 @code{rubygems.org} and includes most relevant information, including
8526 runtime dependencies. There are some caveats, however. The metadata
8527 doesn't distinguish between synopses and descriptions, so the same string
8528 is used for both fields. Additionally, the details of non-Ruby
8529 dependencies required to build native extensions is unavailable and left
8530 as an exercise to the packager.
8532 The command below imports metadata for the @code{rails} Ruby package:
8535 guix import gem rails
8541 Traverse the dependency graph of the given upstream package recursively
8542 and generate package expressions for all those packages that are not yet
8548 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
8549 Information is taken from the JSON-formatted metadata provided through
8550 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
8551 relevant information, such as module dependencies. License information
8552 should be checked closely. If Perl is available in the store, then the
8553 @code{corelist} utility will be used to filter core modules out of the
8554 list of dependencies.
8556 The command command below imports metadata for the @code{Acme::Boolean}
8560 guix import cpan Acme::Boolean
8565 @cindex Bioconductor
8566 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
8567 central repository for the @uref{https://r-project.org, GNU@tie{}R
8568 statistical and graphical environment}.
8570 Information is extracted from the @code{DESCRIPTION} file of the package.
8572 The command command below imports metadata for the @code{Cairo}
8576 guix import cran Cairo
8579 When @code{--recursive} is added, the importer will traverse the
8580 dependency graph of the given upstream package recursively and generate
8581 package expressions for all those packages that are not yet in Guix.
8583 When @code{--archive=bioconductor} is added, metadata is imported from
8584 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
8585 packages for for the analysis and comprehension of high-throughput
8586 genomic data in bioinformatics.
8588 Information is extracted from the @code{DESCRIPTION} file of a package
8589 published on the web interface of the Bioconductor SVN repository.
8591 The command below imports metadata for the @code{GenomicRanges}
8595 guix import cran --archive=bioconductor GenomicRanges
8601 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
8602 comprehensive TeX archive network for TeX packages that are part of the
8603 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
8605 Information about the package is obtained through the XML API provided
8606 by CTAN, while the source code is downloaded from the SVN repository of
8607 the Tex Live project. This is done because the CTAN does not keep
8610 The command command below imports metadata for the @code{fontspec}
8614 guix import texlive fontspec
8617 When @code{--archive=DIRECTORY} is added, the source code is downloaded
8618 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
8619 tree in the TeX Live SVN repository, but from the specified sibling
8620 directory under the same root.
8622 The command below imports metadata for the @code{ifxetex} package from
8623 CTAN while fetching the sources from the directory
8624 @file{texmf/source/generic}:
8627 guix import texlive --archive=generic ifxetex
8631 @cindex JSON, import
8632 Import package metadata from a local JSON file. Consider the following
8633 example package definition in JSON format:
8639 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
8640 "build-system": "gnu",
8641 "home-page": "https://www.gnu.org/software/hello/",
8642 "synopsis": "Hello, GNU world: An example GNU package",
8643 "description": "GNU Hello prints a greeting.",
8644 "license": "GPL-3.0+",
8645 "native-inputs": ["gcc@@6"]
8649 The field names are the same as for the @code{<package>} record
8650 (@xref{Defining Packages}). References to other packages are provided
8651 as JSON lists of quoted package specification strings such as
8652 @code{guile} or @code{guile@@2.0}.
8654 The importer also supports a more explicit source definition using the
8655 common fields for @code{<origin>} records:
8661 "method": "url-fetch",
8662 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
8664 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
8671 The command below reads metadata from the JSON file @code{hello.json}
8672 and outputs a package expression:
8675 guix import json hello.json
8679 Import metadata from a local copy of the source of the
8680 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
8681 relies on the @command{nix-instantiate} command of
8682 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
8683 typically written in a mixture of Nix-language and Bash code. This
8684 command only imports the high-level package structure that is written in
8685 the Nix language. It normally includes all the basic fields of a
8688 When importing a GNU package, the synopsis and descriptions are replaced
8689 by their canonical upstream variant.
8691 Usually, you will first need to do:
8694 export NIX_REMOTE=daemon
8698 so that @command{nix-instantiate} does not try to open the Nix database.
8700 As an example, the command below imports the package definition of
8701 LibreOffice (more precisely, it imports the definition of the package
8702 bound to the @code{libreoffice} top-level attribute):
8705 guix import nix ~/path/to/nixpkgs libreoffice
8710 Import metadata from the Haskell community's central package archive
8711 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
8712 Cabal files and includes all the relevant information, including package
8715 Specific command-line options are:
8720 Read a Cabal file from standard input.
8721 @item --no-test-dependencies
8723 Do not include dependencies required only by the test suites.
8724 @item --cabal-environment=@var{alist}
8725 @itemx -e @var{alist}
8726 @var{alist} is a Scheme alist defining the environment in which the
8727 Cabal conditionals are evaluated. The accepted keys are: @code{os},
8728 @code{arch}, @code{impl} and a string representing the name of a flag.
8729 The value associated with a flag has to be either the symbol
8730 @code{true} or @code{false}. The value associated with other keys
8731 has to conform to the Cabal file format definition. The default value
8732 associated with the keys @code{os}, @code{arch} and @code{impl} is
8733 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
8736 Traverse the dependency graph of the given upstream package recursively
8737 and generate package expressions for all those packages that are not yet
8741 The command below imports metadata for the latest version of the
8742 @code{HTTP} Haskell package without including test dependencies and
8743 specifying the value of the flag @samp{network-uri} as @code{false}:
8746 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
8749 A specific package version may optionally be specified by following the
8750 package name by an at-sign and a version number as in the following example:
8753 guix import hackage mtl@@2.1.3.1
8758 The @code{stackage} importer is a wrapper around the @code{hackage} one.
8759 It takes a package name, looks up the package version included in a
8760 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
8761 release and uses the @code{hackage} importer to retrieve its metadata.
8762 Note that it is up to you to select an LTS release compatible with the
8763 GHC compiler used by Guix.
8765 Specific command-line options are:
8768 @item --no-test-dependencies
8770 Do not include dependencies required only by the test suites.
8771 @item --lts-version=@var{version}
8772 @itemx -l @var{version}
8773 @var{version} is the desired LTS release version. If omitted the latest
8777 Traverse the dependency graph of the given upstream package recursively
8778 and generate package expressions for all those packages that are not yet
8782 The command below imports metadata for the @code{HTTP} Haskell package
8783 included in the LTS Stackage release version 7.18:
8786 guix import stackage --lts-version=7.18 HTTP
8791 Import metadata from an Emacs Lisp Package Archive (ELPA) package
8792 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
8794 Specific command-line options are:
8797 @item --archive=@var{repo}
8798 @itemx -a @var{repo}
8799 @var{repo} identifies the archive repository from which to retrieve the
8800 information. Currently the supported repositories and their identifiers
8804 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
8805 identifier. This is the default.
8807 Packages from @code{elpa.gnu.org} are signed with one of the keys
8808 contained in the GnuPG keyring at
8809 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
8810 @code{emacs} package (@pxref{Package Installation, ELPA package
8811 signatures,, emacs, The GNU Emacs Manual}).
8814 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
8815 @code{melpa-stable} identifier.
8818 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
8824 Traverse the dependency graph of the given upstream package recursively
8825 and generate package expressions for all those packages that are not yet
8831 Import metadata from the crates.io Rust package repository
8832 @uref{https://crates.io, crates.io}.
8837 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
8838 repository used by the OCaml community.
8841 The structure of the @command{guix import} code is modular. It would be
8842 useful to have more importers for other package formats, and your help
8843 is welcome here (@pxref{Contributing}).
8845 @node Invoking guix refresh
8846 @section Invoking @command{guix refresh}
8848 @cindex @command {guix refresh}
8849 The primary audience of the @command{guix refresh} command is developers
8850 of the GNU software distribution. By default, it reports any packages
8851 provided by the distribution that are outdated compared to the latest
8852 upstream version, like this:
8856 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
8857 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
8860 Alternately, one can specify packages to consider, in which case a
8861 warning is emitted for packages that lack an updater:
8864 $ guix refresh coreutils guile guile-ssh
8865 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
8866 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
8869 @command{guix refresh} browses the upstream repository of each package and determines
8870 the highest version number of the releases therein. The command
8871 knows how to update specific types of packages: GNU packages, ELPA
8872 packages, etc.---see the documentation for @option{--type} below. There
8873 are many packages, though, for which it lacks a method to determine
8874 whether a new upstream release is available. However, the mechanism is
8875 extensible, so feel free to get in touch with us to add a new method!
8880 Consider the packages specified, and all the packages upon which they depend.
8883 $ guix refresh --recursive coreutils
8884 gnu/packages/acl.scm:35:2: warning: no updater for acl
8885 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
8886 gnu/packages/xml.scm:68:2: warning: no updater for expat
8887 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
8893 Sometimes the upstream name differs from the package name used in Guix,
8894 and @command{guix refresh} needs a little help. Most updaters honor the
8895 @code{upstream-name} property in package definitions, which can be used
8899 (define-public network-manager
8901 (name "network-manager")
8903 (properties '((upstream-name . "NetworkManager")))))
8906 When passed @code{--update}, it modifies distribution source files to
8907 update the version numbers and source tarball hashes of those package
8908 recipes (@pxref{Defining Packages}). This is achieved by downloading
8909 each package's latest source tarball and its associated OpenPGP
8910 signature, authenticating the downloaded tarball against its signature
8911 using @command{gpg}, and finally computing its hash. When the public
8912 key used to sign the tarball is missing from the user's keyring, an
8913 attempt is made to automatically retrieve it from a public key server;
8914 when this is successful, the key is added to the user's keyring; otherwise,
8915 @command{guix refresh} reports an error.
8917 The following options are supported:
8921 @item --expression=@var{expr}
8922 @itemx -e @var{expr}
8923 Consider the package @var{expr} evaluates to.
8925 This is useful to precisely refer to a package, as in this example:
8928 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
8931 This command lists the dependents of the ``final'' libc (essentially all
8936 Update distribution source files (package recipes) in place. This is
8937 usually run from a checkout of the Guix source tree (@pxref{Running
8938 Guix Before It Is Installed}):
8941 $ ./pre-inst-env guix refresh -s non-core -u
8944 @xref{Defining Packages}, for more information on package definitions.
8946 @item --select=[@var{subset}]
8947 @itemx -s @var{subset}
8948 Select all the packages in @var{subset}, one of @code{core} or
8951 The @code{core} subset refers to all the packages at the core of the
8952 distribution---i.e., packages that are used to build ``everything
8953 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
8954 changing one of these packages in the distribution entails a rebuild of
8955 all the others. Thus, such updates are an inconvenience to users in
8956 terms of build time or bandwidth used to achieve the upgrade.
8958 The @code{non-core} subset refers to the remaining packages. It is
8959 typically useful in cases where an update of the core packages would be
8962 @item --manifest=@var{file}
8963 @itemx -m @var{file}
8964 Select all the packages from the manifest in @var{file}. This is useful to
8965 check if any packages of the user manifest can be updated.
8967 @item --type=@var{updater}
8968 @itemx -t @var{updater}
8969 Select only packages handled by @var{updater} (may be a comma-separated
8970 list of updaters). Currently, @var{updater} may be one of:
8974 the updater for GNU packages;
8976 the updater for GNOME packages;
8978 the updater for KDE packages;
8980 the updater for X.org packages;
8982 the updater for packages hosted on kernel.org;
8984 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
8986 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
8988 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
8990 the updater for @uref{https://www.cpan.org/, CPAN} packages;
8992 the updater for @uref{https://pypi.python.org, PyPI} packages.
8994 the updater for @uref{https://rubygems.org, RubyGems} packages.
8996 the updater for @uref{https://github.com, GitHub} packages.
8998 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9000 the updater for @uref{https://www.stackage.org, Stackage} packages.
9002 the updater for @uref{https://crates.io, Crates} packages.
9004 the updater for @uref{https://launchpad.net, Launchpad} packages.
9007 For instance, the following command only checks for updates of Emacs
9008 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9011 $ guix refresh --type=elpa,cran
9012 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9013 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9018 In addition, @command{guix refresh} can be passed one or more package
9019 names, as in this example:
9022 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9026 The command above specifically updates the @code{emacs} and
9027 @code{idutils} packages. The @code{--select} option would have no
9028 effect in this case.
9030 When considering whether to upgrade a package, it is sometimes
9031 convenient to know which packages would be affected by the upgrade and
9032 should be checked for compatibility. For this the following option may
9033 be used when passing @command{guix refresh} one or more package names:
9037 @item --list-updaters
9039 List available updaters and exit (see @option{--type} above.)
9041 For each updater, display the fraction of packages it covers; at the
9042 end, display the fraction of packages covered by all these updaters.
9044 @item --list-dependent
9046 List top-level dependent packages that would need to be rebuilt as a
9047 result of upgrading one or more packages.
9049 @xref{Invoking guix graph, the @code{reverse-package} type of
9050 @command{guix graph}}, for information on how to visualize the list of
9051 dependents of a package.
9055 Be aware that the @code{--list-dependent} option only
9056 @emph{approximates} the rebuilds that would be required as a result of
9057 an upgrade. More rebuilds might be required under some circumstances.
9060 $ guix refresh --list-dependent flex
9061 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9062 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9065 The command above lists a set of packages that could be built to check
9066 for compatibility with an upgraded @code{flex} package.
9070 @item --list-transitive
9071 List all the packages which one or more packages depend upon.
9074 $ guix refresh --list-transitive flex
9075 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9076 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{}
9081 The command above lists a set of packages which, when changed, would cause
9082 @code{flex} to be rebuilt.
9084 The following options can be used to customize GnuPG operation:
9088 @item --gpg=@var{command}
9089 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9090 for in @code{$PATH}.
9092 @item --keyring=@var{file}
9093 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9094 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9095 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9096 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9097 information on a tool to manipulate keybox files).
9099 When this option is omitted, @command{guix refresh} uses
9100 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9101 signing keys. OpenPGP signatures are checked against keys from this keyring;
9102 missing keys are downloaded to this keyring as well (see
9103 @option{--key-download} below.)
9105 You can export keys from your default GPG keyring into a keybox file using
9106 commands like this one:
9109 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9112 Likewise, you can fetch keys to a specific keybox file like this:
9115 gpg --no-default-keyring --keyring mykeyring.kbx \
9116 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9119 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9120 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9122 @item --key-download=@var{policy}
9123 Handle missing OpenPGP keys according to @var{policy}, which may be one
9128 Always download missing OpenPGP keys from the key server, and add them
9129 to the user's GnuPG keyring.
9132 Never try to download missing OpenPGP keys. Instead just bail out.
9135 When a package signed with an unknown OpenPGP key is encountered, ask
9136 the user whether to download it or not. This is the default behavior.
9139 @item --key-server=@var{host}
9140 Use @var{host} as the OpenPGP key server when importing a public key.
9144 The @code{github} updater uses the
9145 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9146 releases. When used repeatedly e.g.@: when refreshing all packages,
9147 GitHub will eventually refuse to answer any further API requests. By
9148 default 60 API requests per hour are allowed, and a full refresh on all
9149 GitHub packages in Guix requires more than this. Authentication with
9150 GitHub through the use of an API token alleviates these limits. To use
9151 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9152 token procured from @uref{https://github.com/settings/tokens} or
9156 @node Invoking guix lint
9157 @section Invoking @command{guix lint}
9159 @cindex @command{guix lint}
9160 @cindex package, checking for errors
9161 The @command{guix lint} command is meant to help package developers avoid
9162 common errors and use a consistent style. It runs a number of checks on
9163 a given set of packages in order to find common mistakes in their
9164 definitions. Available @dfn{checkers} include (see
9165 @code{--list-checkers} for a complete list):
9170 Validate certain typographical and stylistic rules about package
9171 descriptions and synopses.
9173 @item inputs-should-be-native
9174 Identify inputs that should most likely be native inputs.
9180 @itemx source-file-name
9181 Probe @code{home-page} and @code{source} URLs and report those that are
9182 invalid. Suggest a @code{mirror://} URL when applicable. If the
9183 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9184 URL. Check that the source file name is meaningful, e.g.@: is not just a
9185 version number or ``git-checkout'', without a declared @code{file-name}
9186 (@pxref{origin Reference}).
9188 @item source-unstable-tarball
9189 Parse the @code{source} URL to determine if a tarball from GitHub is
9190 autogenerated or if it is a release tarball. Unfortunately GitHub's
9191 autogenerated tarballs are sometimes regenerated.
9194 @cindex security vulnerabilities
9195 @cindex CVE, Common Vulnerabilities and Exposures
9196 Report known vulnerabilities found in the Common Vulnerabilities and
9197 Exposures (CVE) databases of the current and past year
9198 @uref{https://nvd.nist.gov/download.cfm#CVE_FEED, published by the US
9201 To view information about a particular vulnerability, visit pages such as:
9205 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9207 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9211 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9212 @code{CVE-2015-7554}.
9214 Package developers can specify in package recipes the
9215 @uref{https://nvd.nist.gov/cpe.cfm,Common Platform Enumeration (CPE)}
9216 name and version of the package when they differ from the name or version
9217 that Guix uses, as in this example:
9223 ;; CPE calls this package "grub2".
9224 (properties '((cpe-name . "grub2")
9225 (cpe-version . "2.3")))
9228 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9229 Some entries in the CVE database do not specify which version of a
9230 package they apply to, and would thus ``stick around'' forever. Package
9231 developers who found CVE alerts and verified they can be ignored can
9232 declare them as in this example:
9238 ;; These CVEs no longer apply and can be safely ignored.
9239 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9242 "CVE-2011-5244")))))
9246 Warn about obvious source code formatting issues: trailing white space,
9247 use of tabulations, etc.
9250 The general syntax is:
9253 guix lint @var{options} @var{package}@dots{}
9256 If no package is given on the command line, then all packages are checked.
9257 The @var{options} may be zero or more of the following:
9260 @item --list-checkers
9262 List and describe all the available checkers that will be run on packages
9267 Only enable the checkers specified in a comma-separated list using the
9268 names returned by @code{--list-checkers}.
9272 @node Invoking guix size
9273 @section Invoking @command{guix size}
9276 @cindex package size
9278 @cindex @command{guix size}
9279 The @command{guix size} command helps package developers profile the
9280 disk usage of packages. It is easy to overlook the impact of an
9281 additional dependency added to a package, or the impact of using a
9282 single output for a package that could easily be split (@pxref{Packages
9283 with Multiple Outputs}). Such are the typical issues that
9284 @command{guix size} can highlight.
9286 The command can be passed one or more package specifications
9287 such as @code{gcc@@4.8}
9288 or @code{guile:debug}, or a file name in the store. Consider this
9292 $ guix size coreutils
9293 store item total self
9294 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9295 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9296 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9297 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9298 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9299 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9300 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9301 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9306 The store items listed here constitute the @dfn{transitive closure} of
9307 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9308 would be returned by:
9311 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9314 Here the output shows three columns next to store items. The first column,
9315 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9316 the store item---that is, its own size plus the size of all its
9317 dependencies. The next column, labeled ``self'', shows the size of the
9318 item itself. The last column shows the ratio of the size of the item
9319 itself to the space occupied by all the items listed here.
9321 In this example, we see that the closure of Coreutils weighs in at
9322 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9323 libraries. (That libc and GCC's libraries represent a large fraction of
9324 the closure is not a problem @i{per se} because they are always available
9325 on the system anyway.)
9327 When the package(s) passed to @command{guix size} are available in the
9328 store@footnote{More precisely, @command{guix size} looks for the
9329 @emph{ungrafted} variant of the given package(s), as returned by
9330 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9331 for information on grafts.}, @command{guix size} queries the daemon to determine its
9332 dependencies, and measures its size in the store, similar to @command{du
9333 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9336 When the given packages are @emph{not} in the store, @command{guix size}
9337 reports information based on the available substitutes
9338 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9339 store items that are not even on disk, only available remotely.
9341 You can also specify several package names:
9344 $ guix size coreutils grep sed bash
9345 store item total self
9346 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9347 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9348 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9349 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9355 In this example we see that the combination of the four packages takes
9356 102.3@tie{}MiB in total, which is much less than the sum of each closure
9357 since they have a lot of dependencies in common.
9359 The available options are:
9363 @item --substitute-urls=@var{urls}
9364 Use substitute information from @var{urls}.
9365 @xref{client-substitute-urls, the same option for @code{guix build}}.
9367 @item --sort=@var{key}
9368 Sort lines according to @var{key}, one of the following options:
9372 the size of each item (the default);
9374 the total size of the item's closure.
9377 @item --map-file=@var{file}
9378 Write a graphical map of disk usage in PNG format to @var{file}.
9380 For the example above, the map looks like this:
9382 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
9383 produced by @command{guix size}}
9385 This option requires that
9386 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
9387 installed and visible in Guile's module search path. When that is not
9388 the case, @command{guix size} fails as it tries to load it.
9390 @item --system=@var{system}
9391 @itemx -s @var{system}
9392 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
9396 @node Invoking guix graph
9397 @section Invoking @command{guix graph}
9400 @cindex @command{guix graph}
9401 @cindex package dependencies
9402 Packages and their dependencies form a @dfn{graph}, specifically a
9403 directed acyclic graph (DAG). It can quickly become difficult to have a
9404 mental model of the package DAG, so the @command{guix graph} command
9405 provides a visual representation of the DAG. By default,
9406 @command{guix graph} emits a DAG representation in the input format of
9407 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
9408 directly to the @command{dot} command of Graphviz. It can also emit an
9409 HTML page with embedded JavaScript code to display a ``chord diagram''
9410 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
9411 emit Cypher queries to construct a graph in a graph database supporting
9412 the @uref{https://www.opencypher.org/, openCypher} query language.
9413 The general syntax is:
9416 guix graph @var{options} @var{package}@dots{}
9419 For example, the following command generates a PDF file representing the
9420 package DAG for the GNU@tie{}Core Utilities, showing its build-time
9424 guix graph coreutils | dot -Tpdf > dag.pdf
9427 The output looks like this:
9429 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
9431 Nice little graph, no?
9433 But there is more than one graph! The one above is concise: it is the
9434 graph of package objects, omitting implicit inputs such as GCC, libc,
9435 grep, etc. It is often useful to have such a concise graph, but
9436 sometimes one may want to see more details. @command{guix graph} supports
9437 several types of graphs, allowing you to choose the level of detail:
9441 This is the default type used in the example above. It shows the DAG of
9442 package objects, excluding implicit dependencies. It is concise, but
9443 filters out many details.
9445 @item reverse-package
9446 This shows the @emph{reverse} DAG of packages. For example:
9449 guix graph --type=reverse-package ocaml
9452 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
9453 you are also interested in cases where OCaml is an implicit dependency, see
9454 @code{reverse-bag} below.)
9456 Note that for core packages this can yield huge graphs. If all you want
9457 is to know the number of packages that depend on a given package, use
9458 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
9459 @option{--list-dependent}}).
9462 This is the package DAG, @emph{including} implicit inputs.
9464 For instance, the following command:
9467 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
9470 ...@: yields this bigger graph:
9472 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
9474 At the bottom of the graph, we see all the implicit inputs of
9475 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
9477 Now, note that the dependencies of these implicit inputs---that is, the
9478 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
9479 here, for conciseness.
9482 Similar to @code{bag-emerged}, but this time including all the bootstrap
9485 @item bag-with-origins
9486 Similar to @code{bag}, but also showing origins and their dependencies.
9489 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
9490 it also takes implicit dependencies into account. For example:
9493 guix graph -t reverse-bag dune
9497 ...@: yields the graph of all packages that depend on Dune, directly or
9498 indirectly. Since Dune is an @emph{implicit} dependency of many packages
9499 @i{via} @code{dune-build-system}, this shows a large number of packages,
9500 whereas @code{reverse-package} would show very few if any.
9503 This is the most detailed representation: It shows the DAG of
9504 derivations (@pxref{Derivations}) and plain store items. Compared to
9505 the above representation, many additional nodes are visible, including
9506 build scripts, patches, Guile modules, etc.
9508 For this type of graph, it is also possible to pass a @file{.drv} file
9509 name instead of a package name, as in:
9512 guix graph -t derivation `guix system build -d my-config.scm`
9516 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
9517 For example, the following command shows the graph for the package
9518 module that defines the @code{guile} package:
9521 guix graph -t module guile | dot -Tpdf > module-graph.pdf
9525 All the types above correspond to @emph{build-time dependencies}. The
9526 following graph type represents the @emph{run-time dependencies}:
9530 This is the graph of @dfn{references} of a package output, as returned
9531 by @command{guix gc --references} (@pxref{Invoking guix gc}).
9533 If the given package output is not available in the store, @command{guix
9534 graph} attempts to obtain dependency information from substitutes.
9536 Here you can also pass a store file name instead of a package name. For
9537 example, the command below produces the reference graph of your profile
9538 (which can be big!):
9541 guix graph -t references `readlink -f ~/.guix-profile`
9545 This is the graph of the @dfn{referrers} of a store item, as returned by
9546 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
9548 This relies exclusively on local information from your store. For
9549 instance, let us suppose that the current Inkscape is available in 10
9550 profiles on your machine; @command{guix graph -t referrers inkscape}
9551 will show a graph rooted at Inkscape and with those 10 profiles linked
9554 It can help determine what is preventing a store item from being garbage
9559 The available options are the following:
9562 @item --type=@var{type}
9563 @itemx -t @var{type}
9564 Produce a graph output of @var{type}, where @var{type} must be one of
9565 the values listed above.
9568 List the supported graph types.
9570 @item --backend=@var{backend}
9571 @itemx -b @var{backend}
9572 Produce a graph using the selected @var{backend}.
9574 @item --list-backends
9575 List the supported graph backends.
9577 Currently, the available backends are Graphviz and d3.js.
9579 @item --expression=@var{expr}
9580 @itemx -e @var{expr}
9581 Consider the package @var{expr} evaluates to.
9583 This is useful to precisely refer to a package, as in this example:
9586 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
9589 @item --system=@var{system}
9590 @itemx -s @var{system}
9591 Display the graph for @var{system}---e.g., @code{i686-linux}.
9593 The package dependency graph is largely architecture-independent, but there
9594 are some architecture-dependent bits that this option allows you to visualize.
9599 @node Invoking guix publish
9600 @section Invoking @command{guix publish}
9602 @cindex @command{guix publish}
9603 The purpose of @command{guix publish} is to enable users to easily share
9604 their store with others, who can then use it as a substitute server
9605 (@pxref{Substitutes}).
9607 When @command{guix publish} runs, it spawns an HTTP server which allows
9608 anyone with network access to obtain substitutes from it. This means
9609 that any machine running Guix can also act as if it were a build farm,
9610 since the HTTP interface is compatible with Cuirass, the software behind
9611 the @code{@value{SUBSTITUTE-SERVER}} build farm.
9613 For security, each substitute is signed, allowing recipients to check
9614 their authenticity and integrity (@pxref{Substitutes}). Because
9615 @command{guix publish} uses the signing key of the system, which is only
9616 readable by the system administrator, it must be started as root; the
9617 @code{--user} option makes it drop root privileges early on.
9619 The signing key pair must be generated before @command{guix publish} is
9620 launched, using @command{guix archive --generate-key} (@pxref{Invoking
9623 The general syntax is:
9626 guix publish @var{options}@dots{}
9629 Running @command{guix publish} without any additional arguments will
9630 spawn an HTTP server on port 8080:
9636 Once a publishing server has been authorized (@pxref{Invoking guix
9637 archive}), the daemon may download substitutes from it:
9640 guix-daemon --substitute-urls=http://example.org:8080
9643 By default, @command{guix publish} compresses archives on the fly as it
9644 serves them. This ``on-the-fly'' mode is convenient in that it requires
9645 no setup and is immediately available. However, when serving lots of
9646 clients, we recommend using the @option{--cache} option, which enables
9647 caching of the archives before they are sent to clients---see below for
9648 details. The @command{guix weather} command provides a handy way to
9649 check what a server provides (@pxref{Invoking guix weather}).
9651 As a bonus, @command{guix publish} also serves as a content-addressed
9652 mirror for source files referenced in @code{origin} records
9653 (@pxref{origin Reference}). For instance, assuming @command{guix
9654 publish} is running on @code{example.org}, the following URL returns the
9655 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
9656 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
9659 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
9662 Obviously, these URLs only work for files that are in the store; in
9663 other cases, they return 404 (``Not Found'').
9665 @cindex build logs, publication
9666 Build logs are available from @code{/log} URLs like:
9669 http://example.org/log/gwspk@dots{}-guile-2.2.3
9673 When @command{guix-daemon} is configured to save compressed build logs,
9674 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
9675 URLs return the compressed log as-is, with an appropriate
9676 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
9677 running @command{guix-daemon} with @code{--log-compression=gzip} since
9678 Web browsers can automatically decompress it, which is not the case with
9681 The following options are available:
9684 @item --port=@var{port}
9685 @itemx -p @var{port}
9686 Listen for HTTP requests on @var{port}.
9688 @item --listen=@var{host}
9689 Listen on the network interface for @var{host}. The default is to
9690 accept connections from any interface.
9692 @item --user=@var{user}
9693 @itemx -u @var{user}
9694 Change privileges to @var{user} as soon as possible---i.e., once the
9695 server socket is open and the signing key has been read.
9697 @item --compression[=@var{method}[:@var{level}]]
9698 @itemx -C [@var{method}[:@var{level}]]
9699 Compress data using the given @var{method} and @var{level}. @var{method} is
9700 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
9703 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
9704 to different compression levels: 1 is the fastest, and 9 is the best
9705 (CPU-intensive). The default is 3.
9707 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
9708 increase in CPU usage; see
9709 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
9712 Unless @option{--cache} is used, compression occurs on the fly and
9713 the compressed streams are not
9714 cached. Thus, to reduce load on the machine that runs @command{guix
9715 publish}, it may be a good idea to choose a low compression level, to
9716 run @command{guix publish} behind a caching proxy, or to use
9717 @option{--cache}. Using @option{--cache} has the advantage that it
9718 allows @command{guix publish} to add @code{Content-Length} HTTP header
9721 This option can be repeated, in which case every substitute gets compressed
9722 using all the selected methods, and all of them are advertised. This is
9723 useful when users may not support all the compression methods: they can select
9724 the one they support.
9726 @item --cache=@var{directory}
9727 @itemx -c @var{directory}
9728 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
9729 and only serve archives that are in cache.
9731 When this option is omitted, archives and meta-data are created
9732 on-the-fly. This can reduce the available bandwidth, especially when
9733 compression is enabled, since this may become CPU-bound. Another
9734 drawback of the default mode is that the length of archives is not known
9735 in advance, so @command{guix publish} does not add a
9736 @code{Content-Length} HTTP header to its responses, which in turn
9737 prevents clients from knowing the amount of data being downloaded.
9739 Conversely, when @option{--cache} is used, the first request for a store
9740 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
9741 background process to @dfn{bake} the archive---computing its
9742 @code{.narinfo} and compressing the archive, if needed. Once the
9743 archive is cached in @var{directory}, subsequent requests succeed and
9744 are served directly from the cache, which guarantees that clients get
9745 the best possible bandwidth.
9747 The ``baking'' process is performed by worker threads. By default, one
9748 thread per CPU core is created, but this can be customized. See
9749 @option{--workers} below.
9751 When @option{--ttl} is used, cached entries are automatically deleted
9752 when they have expired.
9754 @item --workers=@var{N}
9755 When @option{--cache} is used, request the allocation of @var{N} worker
9756 threads to ``bake'' archives.
9758 @item --ttl=@var{ttl}
9759 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
9760 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
9761 days, @code{1m} means 1 month, and so on.
9763 This allows the user's Guix to keep substitute information in cache for
9764 @var{ttl}. However, note that @code{guix publish} does not itself
9765 guarantee that the store items it provides will indeed remain available
9766 for as long as @var{ttl}.
9768 Additionally, when @option{--cache} is used, cached entries that have
9769 not been accessed for @var{ttl} and that no longer have a corresponding
9770 item in the store, may be deleted.
9772 @item --nar-path=@var{path}
9773 Use @var{path} as the prefix for the URLs of ``nar'' files
9774 (@pxref{Invoking guix archive, normalized archives}).
9776 By default, nars are served at a URL such as
9777 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
9778 change the @code{/nar} part to @var{path}.
9780 @item --public-key=@var{file}
9781 @itemx --private-key=@var{file}
9782 Use the specific @var{file}s as the public/private key pair used to sign
9783 the store items being published.
9785 The files must correspond to the same key pair (the private key is used
9786 for signing and the public key is merely advertised in the signature
9787 metadata). They must contain keys in the canonical s-expression format
9788 as produced by @command{guix archive --generate-key} (@pxref{Invoking
9789 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
9790 @file{/etc/guix/signing-key.sec} are used.
9792 @item --repl[=@var{port}]
9793 @itemx -r [@var{port}]
9794 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
9795 Reference Manual}) on @var{port} (37146 by default). This is used
9796 primarily for debugging a running @command{guix publish} server.
9799 Enabling @command{guix publish} on Guix System is a one-liner: just
9800 instantiate a @code{guix-publish-service-type} service in the @code{services} field
9801 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
9802 @code{guix-publish-service-type}}).
9804 If you are instead running Guix on a ``foreign distro'', follow these
9809 If your host distro uses the systemd init system:
9812 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
9813 /etc/systemd/system/
9814 # systemctl start guix-publish && systemctl enable guix-publish
9818 If your host distro uses the Upstart init system:
9821 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
9822 # start guix-publish
9826 Otherwise, proceed similarly with your distro's init system.
9829 @node Invoking guix challenge
9830 @section Invoking @command{guix challenge}
9832 @cindex reproducible builds
9833 @cindex verifiable builds
9834 @cindex @command{guix challenge}
9836 Do the binaries provided by this server really correspond to the source
9837 code it claims to build? Is a package build process deterministic?
9838 These are the questions the @command{guix challenge} command attempts to
9841 The former is obviously an important question: Before using a substitute
9842 server (@pxref{Substitutes}), one had better @emph{verify} that it
9843 provides the right binaries, and thus @emph{challenge} it. The latter
9844 is what enables the former: If package builds are deterministic, then
9845 independent builds of the package should yield the exact same result,
9846 bit for bit; if a server provides a binary different from the one
9847 obtained locally, it may be either corrupt or malicious.
9849 We know that the hash that shows up in @file{/gnu/store} file names is
9850 the hash of all the inputs of the process that built the file or
9851 directory---compilers, libraries, build scripts,
9852 etc. (@pxref{Introduction}). Assuming deterministic build processes,
9853 one store file name should map to exactly one build output.
9854 @command{guix challenge} checks whether there is, indeed, a single
9855 mapping by comparing the build outputs of several independent builds of
9856 any given store item.
9858 The command output looks like this:
9861 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
9862 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
9863 updating list of substitutes from 'https://guix.example.org'... 100.0%
9864 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
9865 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9866 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9867 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
9868 /gnu/store/@dots{}-git-2.5.0 contents differ:
9869 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
9870 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
9871 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
9872 /gnu/store/@dots{}-pius-2.1.1 contents differ:
9873 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9874 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9875 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
9879 6,406 store items were analyzed:
9880 - 4,749 (74.1%) were identical
9881 - 525 (8.2%) differed
9882 - 1,132 (17.7%) were inconclusive
9886 In this example, @command{guix challenge} first scans the store to
9887 determine the set of locally-built derivations---as opposed to store
9888 items that were downloaded from a substitute server---and then queries
9889 all the substitute servers. It then reports those store items for which
9890 the servers obtained a result different from the local build.
9892 @cindex non-determinism, in package builds
9893 As an example, @code{guix.example.org} always gets a different answer.
9894 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
9895 case of Git. This might indicate that the build process of Git is
9896 non-deterministic, meaning that its output varies as a function of
9897 various things that Guix does not fully control, in spite of building
9898 packages in isolated environments (@pxref{Features}). Most common
9899 sources of non-determinism include the addition of timestamps in build
9900 results, the inclusion of random numbers, and directory listings sorted
9901 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
9904 To find out what is wrong with this Git binary, we can do something along
9905 these lines (@pxref{Invoking guix archive}):
9908 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0 \
9909 | guix archive -x /tmp/git
9910 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
9913 This command shows the difference between the files resulting from the
9914 local build, and the files resulting from the build on
9915 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
9916 diffutils, Comparing and Merging Files}). The @command{diff} command
9917 works great for text files. When binary files differ, a better option
9918 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
9919 visualize differences for all kinds of files.
9921 Once you have done that work, you can tell whether the differences are due
9922 to a non-deterministic build process or to a malicious server. We try
9923 hard to remove sources of non-determinism in packages to make it easier
9924 to verify substitutes, but of course, this is a process that
9925 involves not just Guix, but a large part of the free software community.
9926 In the meantime, @command{guix challenge} is one tool to help address
9929 If you are writing packages for Guix, you are encouraged to check
9930 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
9931 same build result as you did with:
9934 $ guix challenge @var{package}
9938 where @var{package} is a package specification such as
9939 @code{guile@@2.0} or @code{glibc:debug}.
9941 The general syntax is:
9944 guix challenge @var{options} [@var{packages}@dots{}]
9947 When a difference is found between the hash of a locally-built item and
9948 that of a server-provided substitute, or among substitutes provided by
9949 different servers, the command displays it as in the example above and
9950 its exit code is 2 (other non-zero exit codes denote other kinds of
9953 The one option that matters is:
9957 @item --substitute-urls=@var{urls}
9958 Consider @var{urls} the whitespace-separated list of substitute source
9963 Show details about matches (identical contents) in addition to
9964 information about mismatches.
9968 @node Invoking guix copy
9969 @section Invoking @command{guix copy}
9971 @cindex copy, of store items, over SSH
9972 @cindex SSH, copy of store items
9973 @cindex sharing store items across machines
9974 @cindex transferring store items across machines
9975 The @command{guix copy} command copies items from the store of one
9976 machine to that of another machine over a secure shell (SSH)
9977 connection@footnote{This command is available only when Guile-SSH was
9978 found. @xref{Requirements}, for details.}. For example, the following
9979 command copies the @code{coreutils} package, the user's profile, and all
9980 their dependencies over to @var{host}, logged in as @var{user}:
9983 guix copy --to=@var{user}@@@var{host} \
9984 coreutils `readlink -f ~/.guix-profile`
9987 If some of the items to be copied are already present on @var{host},
9988 they are not actually sent.
9990 The command below retrieves @code{libreoffice} and @code{gimp} from
9991 @var{host}, assuming they are available there:
9994 guix copy --from=@var{host} libreoffice gimp
9997 The SSH connection is established using the Guile-SSH client, which is
9998 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
9999 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10001 The key used to sign items that are sent must be accepted by the remote
10002 machine. Likewise, the key used by the remote machine to sign items you
10003 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10004 own daemon. @xref{Invoking guix archive}, for more information about
10005 store item authentication.
10007 The general syntax is:
10010 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10013 You must always specify one of the following options:
10016 @item --to=@var{spec}
10017 @itemx --from=@var{spec}
10018 Specify the host to send to or receive from. @var{spec} must be an SSH
10019 spec such as @code{example.org}, @code{charlie@@example.org}, or
10020 @code{charlie@@example.org:2222}.
10023 The @var{items} can be either package names, such as @code{gimp}, or
10024 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10026 When specifying the name of a package to send, it is first built if
10027 needed, unless @option{--dry-run} was specified. Common build options
10028 are supported (@pxref{Common Build Options}).
10031 @node Invoking guix container
10032 @section Invoking @command{guix container}
10034 @cindex @command{guix container}
10036 As of version @value{VERSION}, this tool is experimental. The interface
10037 is subject to radical change in the future.
10040 The purpose of @command{guix container} is to manipulate processes
10041 running within an isolated environment, commonly known as a
10042 ``container'', typically created by the @command{guix environment}
10043 (@pxref{Invoking guix environment}) and @command{guix system container}
10044 (@pxref{Invoking guix system}) commands.
10046 The general syntax is:
10049 guix container @var{action} @var{options}@dots{}
10052 @var{action} specifies the operation to perform with a container, and
10053 @var{options} specifies the context-specific arguments for the action.
10055 The following actions are available:
10059 Execute a command within the context of a running container.
10064 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10067 @var{pid} specifies the process ID of the running container.
10068 @var{program} specifies an executable file name within the root file
10069 system of the container. @var{arguments} are the additional options that
10070 will be passed to @var{program}.
10072 The following command launches an interactive login shell inside a
10073 Guix system container, started by @command{guix system container}, and whose
10074 process ID is 9001:
10077 guix container exec 9001 /run/current-system/profile/bin/bash --login
10080 Note that the @var{pid} cannot be the parent process of a container. It
10081 must be PID 1 of the container or one of its child processes.
10085 @node Invoking guix weather
10086 @section Invoking @command{guix weather}
10088 Occasionally you're grumpy because substitutes are lacking and you end
10089 up building packages by yourself (@pxref{Substitutes}). The
10090 @command{guix weather} command reports on substitute availability on the
10091 specified servers so you can have an idea of whether you'll be grumpy
10092 today. It can sometimes be useful info as a user, but it is primarily
10093 useful to people running @command{guix publish} (@pxref{Invoking guix
10096 @cindex statistics, for substitutes
10097 @cindex availability of substitutes
10098 @cindex substitute availability
10099 @cindex weather, substitute availability
10100 Here's a sample run:
10103 $ guix weather --substitute-urls=https://guix.example.org
10104 computing 5,872 package derivations for x86_64-linux...
10105 looking for 6,128 store items on https://guix.example.org..
10106 updating list of substitutes from 'https://guix.example.org'... 100.0%
10107 https://guix.example.org
10108 43.4% substitutes available (2,658 out of 6,128)
10109 7,032.5 MiB of nars (compressed)
10110 19,824.2 MiB on disk (uncompressed)
10111 0.030 seconds per request (182.9 seconds in total)
10112 33.5 requests per second
10114 9.8% (342 out of 3,470) of the missing items are queued
10116 x86_64-linux: 518 (59.7%)
10117 i686-linux: 221 (25.5%)
10118 aarch64-linux: 128 (14.8%)
10119 build rate: 23.41 builds per hour
10120 x86_64-linux: 11.16 builds per hour
10121 i686-linux: 6.03 builds per hour
10122 aarch64-linux: 6.41 builds per hour
10125 @cindex continuous integration, statistics
10126 As you can see, it reports the fraction of all the packages for which
10127 substitutes are available on the server---regardless of whether
10128 substitutes are enabled, and regardless of whether this server's signing
10129 key is authorized. It also reports the size of the compressed archives
10130 (``nars'') provided by the server, the size the corresponding store
10131 items occupy in the store (assuming deduplication is turned off), and
10132 the server's throughput. The second part gives continuous integration
10133 (CI) statistics, if the server supports it. In addition, using the
10134 @option{--coverage} option, @command{guix weather} can list ``important''
10135 package substitutes missing on the server (see below).
10137 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10138 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10139 challenge}, it ignores signatures on those substitutes, which is
10140 innocuous since the command only gathers statistics and cannot install
10143 The general syntax is:
10146 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10149 When @var{packages} is omitted, @command{guix weather} checks the availability
10150 of substitutes for @emph{all} the packages, or for those specified with
10151 @option{--manifest}; otherwise it only considers the specified packages. It
10152 is also possible to query specific system types with @option{--system}. The
10153 available options are listed below.
10156 @item --substitute-urls=@var{urls}
10157 @var{urls} is the space-separated list of substitute server URLs to
10158 query. When this option is omitted, the default set of substitute
10159 servers is queried.
10161 @item --system=@var{system}
10162 @itemx -s @var{system}
10163 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10164 option can be repeated, in which case @command{guix weather} will query
10165 substitutes for several system types.
10167 @item --manifest=@var{file}
10168 Instead of querying substitutes for all the packages, only ask for those
10169 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10170 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10173 @item --coverage[=@var{count}]
10174 @itemx -c [@var{count}]
10175 Report on substitute coverage for packages: list packages with at least
10176 @var{count} dependents (zero by default) for which substitutes are
10177 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10178 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10179 @var{b} usually lacks substitutes as well. The result looks like this:
10182 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10183 computing 8,983 package derivations for x86_64-linux...
10184 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10185 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10186 @value{SUBSTITUTE-URL}
10187 64.7% substitutes available (6,047 out of 9,343)
10189 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10190 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10191 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10192 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10196 What this example shows is that @code{kcoreaddons} and presumably the 58
10197 packages that depend on it have no substitutes at @code{ci.guix.info};
10198 likewise for @code{qgpgme} and the 46 packages that depend on it.
10200 If you are a Guix developer, or if you are taking care of this build farm,
10201 you'll probably want to have a closer look at these packages: they may simply
10205 @node Invoking guix processes
10206 @section Invoking @command{guix processes}
10208 The @command{guix processes} command can be useful to developers and system
10209 administrators, especially on multi-user machines and on build farms: it lists
10210 the current sessions (connections to the daemon), as well as information about
10211 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10212 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10213 listed.}. Here's an example of the information it returns:
10216 $ sudo guix processes
10219 ClientCommand: guix environment --ad-hoc python
10223 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10227 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10228 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10229 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10230 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10231 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10232 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10233 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10236 In this example we see that @command{guix-daemon} has three clients:
10237 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10238 integration tool; their process identifier (PID) is given by the
10239 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10240 @command{guix-daemon} sub-process of this particular session.
10242 The @code{LockHeld} fields show which store items are currently locked by this
10243 session, which corresponds to store items being built or substituted (the
10244 @code{LockHeld} field is not displayed when @command{guix processes} is not
10245 running as root.) Last, by looking at the @code{ChildProcess} field, we
10246 understand that these three builds are being offloaded (@pxref{Daemon Offload
10249 The output is in Recutils format so we can use the handy @command{recsel}
10250 command to select sessions of interest (@pxref{Selection Expressions,,,
10251 recutils, GNU recutils manual}). As an example, the command shows the command
10252 line and PID of the client that triggered the build of a Perl package:
10255 $ sudo guix processes | \
10256 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10258 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10262 @node System Configuration
10263 @chapter System Configuration
10265 @cindex system configuration
10266 Guix System supports a consistent whole-system configuration
10267 mechanism. By that we mean that all aspects of the global system
10268 configuration---such as the available system services, timezone and
10269 locale settings, user accounts---are declared in a single place. Such
10270 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10272 One of the advantages of putting all the system configuration under the
10273 control of Guix is that it supports transactional system upgrades, and
10274 makes it possible to roll back to a previous system instantiation,
10275 should something go wrong with the new one (@pxref{Features}). Another
10276 advantage is that it makes it easy to replicate the exact same configuration
10277 across different machines, or at different points in time, without
10278 having to resort to additional administration tools layered on top of
10279 the own tools of the system.
10280 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10282 This section describes this mechanism. First we focus on the system
10283 administrator's viewpoint---explaining how the system is configured and
10284 instantiated. Then we show how this mechanism can be extended, for
10285 instance to support new system services.
10288 * Using the Configuration System:: Customizing your GNU system.
10289 * operating-system Reference:: Detail of operating-system declarations.
10290 * File Systems:: Configuring file system mounts.
10291 * Mapped Devices:: Block device extra processing.
10292 * User Accounts:: Specifying user accounts.
10293 * Keyboard Layout:: How the system interprets key strokes.
10294 * Locales:: Language and cultural convention settings.
10295 * Services:: Specifying system services.
10296 * Setuid Programs:: Programs running with root privileges.
10297 * X.509 Certificates:: Authenticating HTTPS servers.
10298 * Name Service Switch:: Configuring libc's name service switch.
10299 * Initial RAM Disk:: Linux-Libre bootstrapping.
10300 * Bootloader Configuration:: Configuring the boot loader.
10301 * Invoking guix system:: Instantiating a system configuration.
10302 * Invoking guix deploy:: Deploying a system configuration to a remote host.
10303 * Running Guix in a VM:: How to run Guix System in a virtual machine.
10304 * Defining Services:: Adding new service definitions.
10307 @node Using the Configuration System
10308 @section Using the Configuration System
10310 The operating system is configured by providing an
10311 @code{operating-system} declaration in a file that can then be passed to
10312 the @command{guix system} command (@pxref{Invoking guix system}). A
10313 simple setup, with the default system services, the default Linux-Libre
10314 kernel, initial RAM disk, and boot loader looks like this:
10316 @findex operating-system
10318 @include os-config-bare-bones.texi
10321 This example should be self-describing. Some of the fields defined
10322 above, such as @code{host-name} and @code{bootloader}, are mandatory.
10323 Others, such as @code{packages} and @code{services}, can be omitted, in
10324 which case they get a default value.
10326 Below we discuss the effect of some of the most important fields
10327 (@pxref{operating-system Reference}, for details about all the available
10328 fields), and how to @dfn{instantiate} the operating system using
10329 @command{guix system}.
10331 @unnumberedsubsec Bootloader
10333 @cindex legacy boot, on Intel machines
10334 @cindex BIOS boot, on Intel machines
10337 The @code{bootloader} field describes the method that will be used to boot
10338 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
10339 mode, as in the example above. However, more recent machines rely instead on
10340 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
10341 the @code{bootloader} field should contain something along these lines:
10344 (bootloader-configuration
10345 (bootloader grub-efi-bootloader)
10346 (target "/boot/efi"))
10349 @xref{Bootloader Configuration}, for more information on the available
10350 configuration options.
10352 @unnumberedsubsec Globally-Visible Packages
10354 @vindex %base-packages
10355 The @code{packages} field lists packages that will be globally visible
10356 on the system, for all user accounts---i.e., in every user's @code{PATH}
10357 environment variable---in addition to the per-user profiles
10358 (@pxref{Invoking guix package}). The @code{%base-packages} variable
10359 provides all the tools one would expect for basic user and administrator
10360 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
10361 the GNU Zile lightweight text editor, @command{find}, @command{grep},
10362 etc. The example above adds GNU@tie{}Screen to those,
10363 taken from the @code{(gnu packages screen)}
10364 module (@pxref{Package Modules}). The
10365 @code{(list package output)} syntax can be used to add a specific output
10369 (use-modules (gnu packages))
10370 (use-modules (gnu packages dns))
10374 (packages (cons (list bind "utils")
10378 @findex specification->package
10379 Referring to packages by variable name, like @code{bind} above, has
10380 the advantage of being unambiguous; it also allows typos and such to be
10381 diagnosed right away as ``unbound variables''. The downside is that one
10382 needs to know which module defines which package, and to augment the
10383 @code{use-package-modules} line accordingly. To avoid that, one can use
10384 the @code{specification->package} procedure of the @code{(gnu packages)}
10385 module, which returns the best package for a given name or name and
10389 (use-modules (gnu packages))
10393 (packages (append (map specification->package
10394 '("tcpdump" "htop" "gnupg@@2.0"))
10398 @unnumberedsubsec System Services
10401 @vindex %base-services
10402 The @code{services} field lists @dfn{system services} to be made
10403 available when the system starts (@pxref{Services}).
10404 The @code{operating-system} declaration above specifies that, in
10405 addition to the basic services, we want the OpenSSH secure shell
10406 daemon listening on port 2222 (@pxref{Networking Services,
10407 @code{openssh-service-type}}). Under the hood,
10408 @code{openssh-service-type} arranges so that @command{sshd} is started with the
10409 right command-line options, possibly with supporting configuration files
10410 generated as needed (@pxref{Defining Services}).
10412 @cindex customization, of services
10413 @findex modify-services
10414 Occasionally, instead of using the base services as is, you will want to
10415 customize them. To do this, use @code{modify-services} (@pxref{Service
10416 Reference, @code{modify-services}}) to modify the list.
10418 For example, suppose you want to modify @code{guix-daemon} and Mingetty
10419 (the console log-in) in the @code{%base-services} list (@pxref{Base
10420 Services, @code{%base-services}}). To do that, you can write the
10421 following in your operating system declaration:
10424 (define %my-services
10425 ;; My very own list of services.
10426 (modify-services %base-services
10427 (guix-service-type config =>
10428 (guix-configuration
10430 (use-substitutes? #f)
10431 (extra-options '("--gc-keep-derivations"))))
10432 (mingetty-service-type config =>
10433 (mingetty-configuration
10434 (inherit config)))))
10438 (services %my-services))
10441 This changes the configuration---i.e., the service parameters---of the
10442 @code{guix-service-type} instance, and that of all the
10443 @code{mingetty-service-type} instances in the @code{%base-services} list.
10444 Observe how this is accomplished: first, we arrange for the original
10445 configuration to be bound to the identifier @code{config} in the
10446 @var{body}, and then we write the @var{body} so that it evaluates to the
10447 desired configuration. In particular, notice how we use @code{inherit}
10448 to create a new configuration which has the same values as the old
10449 configuration, but with a few modifications.
10451 @cindex encrypted disk
10452 The configuration for a typical ``desktop'' usage, with an encrypted
10453 root partition, the X11 display
10454 server, GNOME and Xfce (users can choose which of these desktop
10455 environments to use at the log-in screen by pressing @kbd{F1}), network
10456 management, power management, and more, would look like this:
10459 @include os-config-desktop.texi
10462 A graphical system with a choice of lightweight window managers
10463 instead of full-blown desktop environments would look like this:
10466 @include os-config-lightweight-desktop.texi
10469 This example refers to the @file{/boot/efi} file system by its UUID,
10470 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
10471 as returned by the @command{blkid} command.
10473 @xref{Desktop Services}, for the exact list of services provided by
10474 @code{%desktop-services}. @xref{X.509 Certificates}, for background
10475 information about the @code{nss-certs} package that is used here.
10477 Again, @code{%desktop-services} is just a list of service objects. If
10478 you want to remove services from there, you can do so using the
10479 procedures for list filtering (@pxref{SRFI-1 Filtering and
10480 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
10481 following expression returns a list that contains all the services in
10482 @code{%desktop-services} minus the Avahi service:
10485 (remove (lambda (service)
10486 (eq? (service-kind service) avahi-service-type))
10490 @unnumberedsubsec Instantiating the System
10492 Assuming the @code{operating-system} declaration
10493 is stored in the @file{my-system-config.scm}
10494 file, the @command{guix system reconfigure my-system-config.scm} command
10495 instantiates that configuration, and makes it the default GRUB boot
10496 entry (@pxref{Invoking guix system}).
10498 The normal way to change the system configuration is by updating this
10499 file and re-running @command{guix system reconfigure}. One should never
10500 have to touch files in @file{/etc} or to run commands that modify the
10501 system state such as @command{useradd} or @command{grub-install}. In
10502 fact, you must avoid that since that would not only void your warranty
10503 but also prevent you from rolling back to previous versions of your
10504 system, should you ever need to.
10506 @cindex roll-back, of the operating system
10507 Speaking of roll-back, each time you run @command{guix system
10508 reconfigure}, a new @dfn{generation} of the system is created---without
10509 modifying or deleting previous generations. Old system generations get
10510 an entry in the bootloader boot menu, allowing you to boot them in case
10511 something went wrong with the latest generation. Reassuring, no? The
10512 @command{guix system list-generations} command lists the system
10513 generations available on disk. It is also possible to roll back the
10514 system via the commands @command{guix system roll-back} and
10515 @command{guix system switch-generation}.
10517 Although the @command{guix system reconfigure} command will not modify
10518 previous generations, you must take care when the current generation is not
10519 the latest (e.g., after invoking @command{guix system roll-back}), since
10520 the operation might overwrite a later generation (@pxref{Invoking guix
10523 @unnumberedsubsec The Programming Interface
10525 At the Scheme level, the bulk of an @code{operating-system} declaration
10526 is instantiated with the following monadic procedure (@pxref{The Store
10529 @deffn {Monadic Procedure} operating-system-derivation os
10530 Return a derivation that builds @var{os}, an @code{operating-system}
10531 object (@pxref{Derivations}).
10533 The output of the derivation is a single directory that refers to all
10534 the packages, configuration files, and other supporting files needed to
10535 instantiate @var{os}.
10538 This procedure is provided by the @code{(gnu system)} module. Along
10539 with @code{(gnu services)} (@pxref{Services}), this module contains the
10540 guts of Guix System. Make sure to visit it!
10543 @node operating-system Reference
10544 @section @code{operating-system} Reference
10546 This section summarizes all the options available in
10547 @code{operating-system} declarations (@pxref{Using the Configuration
10550 @deftp {Data Type} operating-system
10551 This is the data type representing an operating system configuration.
10552 By that, we mean all the global system configuration, not per-user
10553 configuration (@pxref{Using the Configuration System}).
10556 @item @code{kernel} (default: @var{linux-libre})
10557 The package object of the operating system kernel to use@footnote{Currently
10558 only the Linux-libre kernel is supported. In the future, it will be
10559 possible to use the GNU@tie{}Hurd.}.
10561 @item @code{kernel-arguments} (default: @code{'("quiet")})
10562 List of strings or gexps representing additional arguments to pass on
10563 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
10565 @item @code{bootloader}
10566 The system bootloader configuration object. @xref{Bootloader Configuration}.
10569 This is the label (a string) as it appears in the bootloader's menu entry.
10570 The default label includes the kernel name and version.
10572 @item @code{keyboard-layout} (default: @code{#f})
10573 This field specifies the keyboard layout to use in the console. It can be
10574 either @code{#f}, in which case the default keyboard layout is used (usually
10575 US English), or a @code{<keyboard-layout>} record.
10577 This keyboard layout is in effect as soon as the kernel has booted. For
10578 instance, it is the keyboard layout in effect when you type a passphrase if
10579 your root file system is on a @code{luks-device-mapping} mapped device
10580 (@pxref{Mapped Devices}).
10583 This does @emph{not} specify the keyboard layout used by the bootloader, nor
10584 that used by the graphical display server. @xref{Bootloader Configuration},
10585 for information on how to specify the bootloader's keyboard layout. @xref{X
10586 Window}, for information on how to specify the keyboard layout used by the X
10590 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
10592 @cindex initial RAM disk
10593 The list of Linux kernel modules that need to be available in the
10594 initial RAM disk. @xref{Initial RAM Disk}.
10596 @item @code{initrd} (default: @code{base-initrd})
10597 A procedure that returns an initial RAM disk for the Linux
10598 kernel. This field is provided to support low-level customization and
10599 should rarely be needed for casual use. @xref{Initial RAM Disk}.
10601 @item @code{firmware} (default: @code{%base-firmware})
10603 List of firmware packages loadable by the operating system kernel.
10605 The default includes firmware needed for Atheros- and Broadcom-based
10606 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
10607 respectively). @xref{Hardware Considerations}, for more info on
10608 supported hardware.
10610 @item @code{host-name}
10613 @item @code{hosts-file}
10615 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
10616 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
10617 Reference Manual}). The default is a file with entries for
10618 @code{localhost} and @var{host-name}.
10620 @item @code{mapped-devices} (default: @code{'()})
10621 A list of mapped devices. @xref{Mapped Devices}.
10623 @item @code{file-systems}
10624 A list of file systems. @xref{File Systems}.
10626 @item @code{swap-devices} (default: @code{'()})
10627 @cindex swap devices
10628 A list of strings identifying devices or files to be used for ``swap
10629 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
10630 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
10631 It is possible to specify a swap file in a file system on a mapped
10632 device, provided that the necessary device mapping and file system are
10633 also specified. @xref{Mapped Devices} and @ref{File Systems}.
10635 @item @code{users} (default: @code{%base-user-accounts})
10636 @itemx @code{groups} (default: @code{%base-groups})
10637 List of user accounts and groups. @xref{User Accounts}.
10639 If the @code{users} list lacks a user account with UID@tie{}0, a
10640 ``root'' account with UID@tie{}0 is automatically added.
10642 @item @code{skeletons} (default: @code{(default-skeletons)})
10643 A list target file name/file-like object tuples (@pxref{G-Expressions,
10644 file-like objects}). These are the skeleton files that will be added to
10645 the home directory of newly-created user accounts.
10647 For instance, a valid value may look like this:
10650 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
10651 (".guile" ,(plain-file "guile"
10652 "(use-modules (ice-9 readline))
10653 (activate-readline)")))
10656 @item @code{issue} (default: @code{%default-issue})
10657 A string denoting the contents of the @file{/etc/issue} file, which is
10658 displayed when users log in on a text console.
10660 @item @code{packages} (default: @code{%base-packages})
10661 The set of packages installed in the global profile, which is accessible
10662 at @file{/run/current-system/profile}.
10664 The default set includes core utilities and it is good practice to
10665 install non-core utilities in user profiles (@pxref{Invoking guix
10668 @item @code{timezone}
10669 A timezone identifying string---e.g., @code{"Europe/Paris"}.
10671 You can run the @command{tzselect} command to find out which timezone
10672 string corresponds to your region. Choosing an invalid timezone name
10673 causes @command{guix system} to fail.
10675 @item @code{locale} (default: @code{"en_US.utf8"})
10676 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
10677 Library Reference Manual}). @xref{Locales}, for more information.
10679 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
10680 The list of locale definitions to be compiled and that may be used at
10681 run time. @xref{Locales}.
10683 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
10684 The list of GNU@tie{}libc packages whose locale data and tools are used
10685 to build the locale definitions. @xref{Locales}, for compatibility
10686 considerations that justify this option.
10688 @item @code{name-service-switch} (default: @code{%default-nss})
10689 Configuration of the libc name service switch (NSS)---a
10690 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
10693 @item @code{services} (default: @code{%base-services})
10694 A list of service objects denoting system services. @xref{Services}.
10696 @cindex essential services
10697 @item @code{essential-services} (default: ...)
10698 The list of ``essential services''---i.e., things like instances of
10699 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
10700 Reference}), which are derived from the operating system definition itself.
10701 As a user you should @emph{never} need to touch this field.
10703 @item @code{pam-services} (default: @code{(base-pam-services)})
10705 @cindex pluggable authentication modules
10706 Linux @dfn{pluggable authentication module} (PAM) services.
10707 @c FIXME: Add xref to PAM services section.
10709 @item @code{setuid-programs} (default: @var{%setuid-programs})
10710 List of string-valued G-expressions denoting setuid programs.
10711 @xref{Setuid Programs}.
10713 @item @code{sudoers-file} (default: @var{%sudoers-specification})
10714 @cindex sudoers file
10715 The contents of the @file{/etc/sudoers} file as a file-like object
10716 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
10718 This file specifies which users can use the @command{sudo} command, what
10719 they are allowed to do, and what privileges they may gain. The default
10720 is that only @code{root} and members of the @code{wheel} group may use
10725 @deffn {Scheme Syntax} this-operating-system
10726 When used in the @emph{lexical scope} of an operating system field definition,
10727 this identifier resolves to the operating system being defined.
10729 The example below shows how to refer to the operating system being defined in
10730 the definition of the @code{label} field:
10733 (use-modules (gnu) (guix))
10737 (label (package-full-name
10738 (operating-system-kernel this-operating-system))))
10741 It is an error to refer to @code{this-operating-system} outside an operating
10748 @section File Systems
10750 The list of file systems to be mounted is specified in the
10751 @code{file-systems} field of the operating system declaration
10752 (@pxref{Using the Configuration System}). Each file system is declared
10753 using the @code{file-system} form, like this:
10757 (mount-point "/home")
10758 (device "/dev/sda3")
10762 As usual, some of the fields are mandatory---those shown in the example
10763 above---while others can be omitted. These are described below.
10765 @deftp {Data Type} file-system
10766 Objects of this type represent file systems to be mounted. They
10767 contain the following members:
10771 This is a string specifying the type of the file system---e.g.,
10774 @item @code{mount-point}
10775 This designates the place where the file system is to be mounted.
10777 @item @code{device}
10778 This names the ``source'' of the file system. It can be one of three
10779 things: a file system label, a file system UUID, or the name of a
10780 @file{/dev} node. Labels and UUIDs offer a way to refer to file
10781 systems without having to hard-code their actual device
10782 name@footnote{Note that, while it is tempting to use
10783 @file{/dev/disk/by-uuid} and similar device names to achieve the same
10784 result, this is not recommended: These special device nodes are created
10785 by the udev daemon and may be unavailable at the time the device is
10788 @findex file-system-label
10789 File system labels are created using the @code{file-system-label}
10790 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
10791 plain strings. Here's an example of a file system referred to by its
10792 label, as shown by the @command{e2label} command:
10796 (mount-point "/home")
10798 (device (file-system-label "my-home")))
10802 UUIDs are converted from their string representation (as shown by the
10803 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
10804 @code{uuid} form expects 16-byte UUIDs as defined in
10805 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
10806 form of UUID used by the ext2 family of file systems and others, but it
10807 is different from ``UUIDs'' found in FAT file systems, for instance.},
10812 (mount-point "/home")
10814 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
10817 When the source of a file system is a mapped device (@pxref{Mapped
10818 Devices}), its @code{device} field @emph{must} refer to the mapped
10819 device name---e.g., @file{"/dev/mapper/root-partition"}.
10820 This is required so that
10821 the system knows that mounting the file system depends on having the
10822 corresponding device mapping established.
10824 @item @code{flags} (default: @code{'()})
10825 This is a list of symbols denoting mount flags. Recognized flags
10826 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
10827 access to special files), @code{no-suid} (ignore setuid and setgid
10828 bits), @code{no-atime} (do not update file access times), and @code{no-exec}
10829 (disallow program execution). @xref{Mount-Unmount-Remount,,, libc, The GNU C
10830 Library Reference Manual}, for more information on these flags.
10832 @item @code{options} (default: @code{#f})
10833 This is either @code{#f}, or a string denoting mount options passed to the
10834 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
10835 Reference Manual}, for details and run @command{man 8 mount} for options for
10836 various file systems.
10838 @item @code{mount?} (default: @code{#t})
10839 This value indicates whether to automatically mount the file system when
10840 the system is brought up. When set to @code{#f}, the file system gets
10841 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
10842 is not automatically mounted.
10844 @item @code{needed-for-boot?} (default: @code{#f})
10845 This Boolean value indicates whether the file system is needed when
10846 booting. If that is true, then the file system is mounted when the
10847 initial RAM disk (initrd) is loaded. This is always the case, for
10848 instance, for the root file system.
10850 @item @code{check?} (default: @code{#t})
10851 This Boolean indicates whether the file system needs to be checked for
10852 errors before being mounted.
10854 @item @code{create-mount-point?} (default: @code{#f})
10855 When true, the mount point is created if it does not exist yet.
10857 @item @code{dependencies} (default: @code{'()})
10858 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
10859 representing file systems that must be mounted or mapped devices that
10860 must be opened before (and unmounted or closed after) this one.
10862 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
10863 a dependency of @file{/sys/fs/cgroup/cpu} and
10864 @file{/sys/fs/cgroup/memory}.
10866 Another example is a file system that depends on a mapped device, for
10867 example for an encrypted partition (@pxref{Mapped Devices}).
10871 The @code{(gnu system file-systems)} exports the following useful
10874 @defvr {Scheme Variable} %base-file-systems
10875 These are essential file systems that are required on normal systems,
10876 such as @var{%pseudo-terminal-file-system} and @var{%immutable-store} (see
10877 below.) Operating system declarations should always contain at least
10881 @defvr {Scheme Variable} %pseudo-terminal-file-system
10882 This is the file system to be mounted as @file{/dev/pts}. It supports
10883 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
10884 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
10885 Manual}). Pseudo-terminals are used by terminal emulators such as
10889 @defvr {Scheme Variable} %shared-memory-file-system
10890 This file system is mounted as @file{/dev/shm} and is used to support
10891 memory sharing across processes (@pxref{Memory-mapped I/O,
10892 @code{shm_open},, libc, The GNU C Library Reference Manual}).
10895 @defvr {Scheme Variable} %immutable-store
10896 This file system performs a read-only ``bind mount'' of
10897 @file{/gnu/store}, making it read-only for all the users including
10898 @code{root}. This prevents against accidental modification by software
10899 running as @code{root} or by system administrators.
10901 The daemon itself is still able to write to the store: it remounts it
10902 read-write in its own ``name space.''
10905 @defvr {Scheme Variable} %binary-format-file-system
10906 The @code{binfmt_misc} file system, which allows handling of arbitrary
10907 executable file types to be delegated to user space. This requires the
10908 @code{binfmt.ko} kernel module to be loaded.
10911 @defvr {Scheme Variable} %fuse-control-file-system
10912 The @code{fusectl} file system, which allows unprivileged users to mount
10913 and unmount user-space FUSE file systems. This requires the
10914 @code{fuse.ko} kernel module to be loaded.
10917 @node Mapped Devices
10918 @section Mapped Devices
10920 @cindex device mapping
10921 @cindex mapped devices
10922 The Linux kernel has a notion of @dfn{device mapping}: a block device,
10923 such as a hard disk partition, can be @dfn{mapped} into another device,
10924 usually in @code{/dev/mapper/},
10925 with additional processing over the data that flows through
10926 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
10927 concept of a ``mapped device'' and that of a file system: both boil down
10928 to @emph{translating} input/output operations made on a file to
10929 operations on its backing store. Thus, the Hurd implements mapped
10930 devices, like file systems, using the generic @dfn{translator} mechanism
10931 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
10932 typical example is encryption device mapping: all writes to the mapped
10933 device are encrypted, and all reads are deciphered, transparently.
10934 Guix extends this notion by considering any device or set of devices that
10935 are @dfn{transformed} in some way to create a new device; for instance,
10936 RAID devices are obtained by @dfn{assembling} several other devices, such
10937 as hard disks or partitions, into a new one that behaves as one partition.
10938 Other examples, not yet implemented, are LVM logical volumes.
10940 Mapped devices are declared using the @code{mapped-device} form,
10941 defined as follows; for examples, see below.
10943 @deftp {Data Type} mapped-device
10944 Objects of this type represent device mappings that will be made when
10945 the system boots up.
10949 This is either a string specifying the name of the block device to be mapped,
10950 such as @code{"/dev/sda3"}, or a list of such strings when several devices
10951 need to be assembled for creating a new one.
10954 This string specifies the name of the resulting mapped device. For
10955 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
10956 specifying @code{"my-partition"} leads to the creation of
10957 the @code{"/dev/mapper/my-partition"} device.
10958 For RAID devices of type @code{raid-device-mapping}, the full device name
10959 such as @code{"/dev/md0"} needs to be given.
10962 This must be a @code{mapped-device-kind} object, which specifies how
10963 @var{source} is mapped to @var{target}.
10967 @defvr {Scheme Variable} luks-device-mapping
10968 This defines LUKS block device encryption using the @command{cryptsetup}
10969 command from the package with the same name. It relies on the
10970 @code{dm-crypt} Linux kernel module.
10973 @defvr {Scheme Variable} raid-device-mapping
10974 This defines a RAID device, which is assembled using the @code{mdadm}
10975 command from the package with the same name. It requires a Linux kernel
10976 module for the appropriate RAID level to be loaded, such as @code{raid456}
10977 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
10980 @cindex disk encryption
10982 The following example specifies a mapping from @file{/dev/sda3} to
10983 @file{/dev/mapper/home} using LUKS---the
10984 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
10985 standard mechanism for disk encryption.
10986 The @file{/dev/mapper/home}
10987 device can then be used as the @code{device} of a @code{file-system}
10988 declaration (@pxref{File Systems}).
10992 (source "/dev/sda3")
10994 (type luks-device-mapping))
10997 Alternatively, to become independent of device numbering, one may obtain
10998 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11002 cryptsetup luksUUID /dev/sda3
11005 and use it as follows:
11009 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11011 (type luks-device-mapping))
11014 @cindex swap encryption
11015 It is also desirable to encrypt swap space, since swap space may contain
11016 sensitive data. One way to accomplish that is to use a swap file in a
11017 file system on a device mapped via LUKS encryption. In this way, the
11018 swap file is encrypted because the entire device is encrypted.
11019 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11021 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11022 may be declared as follows:
11026 (source (list "/dev/sda1" "/dev/sdb1"))
11027 (target "/dev/md0")
11028 (type raid-device-mapping))
11031 The @file{/dev/md0} device can then be used as the @code{device} of a
11032 @code{file-system} declaration (@pxref{File Systems}).
11033 Note that the RAID level need not be given; it is chosen during the
11034 initial creation and formatting of the RAID device and is determined
11035 automatically later.
11038 @node User Accounts
11039 @section User Accounts
11043 @cindex user accounts
11044 User accounts and groups are entirely managed through the
11045 @code{operating-system} declaration. They are specified with the
11046 @code{user-account} and @code{user-group} forms:
11052 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11053 "audio" ;sound card
11054 "video" ;video devices such as webcams
11055 "cdrom")) ;the good ol' CD-ROM
11056 (comment "Bob's sister")
11057 (home-directory "/home/alice"))
11060 When booting or upon completion of @command{guix system reconfigure},
11061 the system ensures that only the user accounts and groups specified in
11062 the @code{operating-system} declaration exist, and with the specified
11063 properties. Thus, account or group creations or modifications made by
11064 directly invoking commands such as @command{useradd} are lost upon
11065 reconfiguration or reboot. This ensures that the system remains exactly
11068 @deftp {Data Type} user-account
11069 Objects of this type represent user accounts. The following members may
11074 The name of the user account.
11078 This is the name (a string) or identifier (a number) of the user group
11079 this account belongs to.
11081 @item @code{supplementary-groups} (default: @code{'()})
11082 Optionally, this can be defined as a list of group names that this
11083 account belongs to.
11085 @item @code{uid} (default: @code{#f})
11086 This is the user ID for this account (a number), or @code{#f}. In the
11087 latter case, a number is automatically chosen by the system when the
11088 account is created.
11090 @item @code{comment} (default: @code{""})
11091 A comment about the account, such as the account owner's full name.
11093 @item @code{home-directory}
11094 This is the name of the home directory for the account.
11096 @item @code{create-home-directory?} (default: @code{#t})
11097 Indicates whether the home directory of this account should be created
11098 if it does not exist yet.
11100 @item @code{shell} (default: Bash)
11101 This is a G-expression denoting the file name of a program to be used as
11102 the shell (@pxref{G-Expressions}).
11104 @item @code{system?} (default: @code{#f})
11105 This Boolean value indicates whether the account is a ``system''
11106 account. System accounts are sometimes treated specially; for instance,
11107 graphical login managers do not list them.
11109 @anchor{user-account-password}
11110 @cindex password, for user accounts
11111 @item @code{password} (default: @code{#f})
11112 You would normally leave this field to @code{#f}, initialize user
11113 passwords as @code{root} with the @command{passwd} command, and then let
11114 users change it with @command{passwd}. Passwords set with
11115 @command{passwd} are of course preserved across reboot and
11118 If you @emph{do} want to set an initial password for an account, then
11119 this field must contain the encrypted password, as a string. You can use the
11120 @code{crypt} procedure for this purpose:
11127 ;; Specify a SHA-512-hashed initial password.
11128 (password (crypt "InitialPassword!" "$6$abc")))
11132 The hash of this initial password will be available in a file in
11133 @file{/gnu/store}, readable by all the users, so this method must be used with
11137 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11138 more information on password encryption, and @ref{Encryption,,, guile, GNU
11139 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11145 User group declarations are even simpler:
11148 (user-group (name "students"))
11151 @deftp {Data Type} user-group
11152 This type is for, well, user groups. There are just a few fields:
11156 The name of the group.
11158 @item @code{id} (default: @code{#f})
11159 The group identifier (a number). If @code{#f}, a new number is
11160 automatically allocated when the group is created.
11162 @item @code{system?} (default: @code{#f})
11163 This Boolean value indicates whether the group is a ``system'' group.
11164 System groups have low numerical IDs.
11166 @item @code{password} (default: @code{#f})
11167 What, user groups can have a password? Well, apparently yes. Unless
11168 @code{#f}, this field specifies the password of the group.
11173 For convenience, a variable lists all the basic user groups one may
11176 @defvr {Scheme Variable} %base-groups
11177 This is the list of basic user groups that users and/or packages expect
11178 to be present on the system. This includes groups such as ``root'',
11179 ``wheel'', and ``users'', as well as groups used to control access to
11180 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11183 @defvr {Scheme Variable} %base-user-accounts
11184 This is the list of basic system accounts that programs may expect to
11185 find on a GNU/Linux system, such as the ``nobody'' account.
11187 Note that the ``root'' account is not included here. It is a
11188 special-case and is automatically added whether or not it is specified.
11191 @node Keyboard Layout
11192 @section Keyboard Layout
11194 @cindex keyboard layout
11196 To specify what each key of your keyboard does, you need to tell the operating
11197 system what @dfn{keyboard layout} you want to use. The default, when nothing
11198 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11199 However, German speakers will usually prefer the German QWERTZ layout, French
11200 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11201 or bépo, and they might even want to further customize the effect of some of
11202 the keys. This section explains how to get that done.
11204 @cindex keyboard layout, definition
11205 There are three components that will want to know about your keyboard layout:
11209 The @emph{bootloader} may want to know what keyboard layout you want to use
11210 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11211 you want, for instance, to make sure that you can type the passphrase of your
11212 encrypted root partition using the right layout.
11215 The @emph{operating system kernel}, Linux, will need that so that the console
11216 is properly configured (@pxref{operating-system Reference,
11217 @code{keyboard-layout}}).
11220 The @emph{graphical display server}, usually Xorg, also has its own idea of
11221 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11224 Guix allows you to configure all three separately but, fortunately, it allows
11225 you to share the same keyboard layout for all three components.
11227 @cindex XKB, keyboard layouts
11228 Keyboard layouts are represented by records created by the
11229 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11230 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11231 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11232 optional variant name, an optional keyboard model name, and a possibly empty
11233 list of additional options. In most cases the layout name is all you care
11234 about. Here are a few example:
11237 ;; The German QWERTZ layout. Here we assume a standard
11238 ;; "pc105" keyboard model.
11239 (keyboard-layout "de")
11241 ;; The bépo variant of the French layout.
11242 (keyboard-layout "fr" "bepo")
11244 ;; The Catalan layout.
11245 (keyboard-layout "es" "cat")
11247 ;; The Latin American Spanish layout. In addition, the
11248 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11249 ;; and the "Menu" key is used as a "Compose" key to enter
11250 ;; accented letters.
11251 (keyboard-layout "latam"
11252 #:options '("ctrl:nocaps" "compose:menu"))
11254 ;; The Russian layout for a ThinkPad keyboard.
11255 (keyboard-layout "ru" #:model "thinkpad")
11257 ;; The "US international" layout, which is the US layout plus
11258 ;; dead keys to enter accented characters. This is for an
11259 ;; Apple MacBook keyboard.
11260 (keyboard-layout "us" "intl" #:model "macbook78")
11263 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11264 for a complete list of supported layouts, variants, and models.
11266 @cindex keyboard layout, configuration
11267 Let's say you want your system to use the Turkish keyboard layout throughout
11268 your system---bootloader, console, and Xorg. Here's what your system
11269 configuration would look like:
11271 @findex set-xorg-configuration
11273 ;; Using the Turkish layout for the bootloader, the console,
11278 (keyboard-layout (keyboard-layout "tr")) ;for the console
11279 (bootloader (bootloader-configuration
11280 (bootloader grub-efi-bootloader)
11281 (target "/boot/efi")
11282 (keyboard-layout keyboard-layout))) ;for GRUB
11283 (services (cons (set-xorg-configuration
11284 (xorg-configuration ;for Xorg
11285 (keyboard-layout keyboard-layout)))
11286 %desktop-services)))
11289 In the example above, for GRUB and for Xorg, we just refer to the
11290 @code{keyboard-layout} field defined above, but we could just as well refer to
11291 a different layout. The @code{set-xorg-configuration} procedure communicates
11292 the desired Xorg configuration to the graphical log-in manager, by default
11295 We've discussed how to specify the @emph{default} keyboard layout of your
11296 system when it starts, but you can also adjust it at run time:
11300 If you're using GNOME, its settings panel has a ``Region & Language'' entry
11301 where you can select one or more keyboard layouts.
11304 Under Xorg, the @command{setxkbmap} command (from the same-named package)
11305 allows you to change the current layout. For example, this is how you would
11306 change the layout to US Dvorak:
11309 setxkbmap us dvorak
11313 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
11314 console. However, note that @code{loadkeys} does @emph{not} use the XKB
11315 keyboard layout categorization described above. The command below loads the
11316 French bépo layout:
11327 A @dfn{locale} defines cultural conventions for a particular language
11328 and region of the world (@pxref{Locales,,, libc, The GNU C Library
11329 Reference Manual}). Each locale has a name that typically has the form
11330 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
11331 @code{fr_LU.utf8} designates the locale for the French language, with
11332 cultural conventions from Luxembourg, and using the UTF-8 encoding.
11334 @cindex locale definition
11335 Usually, you will want to specify the default locale for the machine
11336 using the @code{locale} field of the @code{operating-system} declaration
11337 (@pxref{operating-system Reference, @code{locale}}).
11339 The selected locale is automatically added to the @dfn{locale
11340 definitions} known to the system if needed, with its codeset inferred
11341 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
11342 @code{UTF-8} codeset. Additional locale definitions can be specified in
11343 the @code{locale-definitions} slot of @code{operating-system}---this is
11344 useful, for instance, if the codeset could not be inferred from the
11345 locale name. The default set of locale definitions includes some widely
11346 used locales, but not all the available locales, in order to save space.
11348 For instance, to add the North Frisian locale for Germany, the value of
11352 (cons (locale-definition
11353 (name "fy_DE.utf8") (source "fy_DE"))
11354 %default-locale-definitions)
11357 Likewise, to save space, one might want @code{locale-definitions} to
11358 list only the locales that are actually used, as in:
11361 (list (locale-definition
11362 (name "ja_JP.eucjp") (source "ja_JP")
11363 (charset "EUC-JP")))
11367 The compiled locale definitions are available at
11368 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
11369 version, which is the default location where the GNU@tie{}libc provided
11370 by Guix looks for locale data. This can be overridden using the
11371 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
11372 @code{LOCPATH} and locale packages}).
11374 The @code{locale-definition} form is provided by the @code{(gnu system
11375 locale)} module. Details are given below.
11377 @deftp {Data Type} locale-definition
11378 This is the data type of a locale definition.
11383 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
11384 Reference Manual}, for more information on locale names.
11386 @item @code{source}
11387 The name of the source for that locale. This is typically the
11388 @code{@var{language}_@var{territory}} part of the locale name.
11390 @item @code{charset} (default: @code{"UTF-8"})
11391 The ``character set'' or ``code set'' for that locale,
11392 @uref{https://www.iana.org/assignments/character-sets, as defined by
11398 @defvr {Scheme Variable} %default-locale-definitions
11399 A list of commonly used UTF-8 locales, used as the default
11400 value of the @code{locale-definitions} field of @code{operating-system}
11403 @cindex locale name
11404 @cindex normalized codeset in locale names
11405 These locale definitions use the @dfn{normalized codeset} for the part
11406 that follows the dot in the name (@pxref{Using gettextized software,
11407 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
11408 instance it has @code{uk_UA.utf8} but @emph{not}, say,
11409 @code{uk_UA.UTF-8}.
11412 @subsection Locale Data Compatibility Considerations
11414 @cindex incompatibility, of locale data
11415 @code{operating-system} declarations provide a @code{locale-libcs} field
11416 to specify the GNU@tie{}libc packages that are used to compile locale
11417 declarations (@pxref{operating-system Reference}). ``Why would I
11418 care?'', you may ask. Well, it turns out that the binary format of
11419 locale data is occasionally incompatible from one libc version to
11422 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
11423 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
11424 For instance, a program linked against libc version 2.21 is unable to
11425 read locale data produced with libc 2.22; worse, that program
11426 @emph{aborts} instead of simply ignoring the incompatible locale
11427 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
11428 the incompatible locale data, which is already an improvement.}.
11429 Similarly, a program linked against libc 2.22 can read most, but not
11430 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
11431 data is incompatible); thus calls to @code{setlocale} may fail, but
11432 programs will not abort.
11434 The ``problem'' with Guix is that users have a lot of freedom: They can
11435 choose whether and when to upgrade software in their profiles, and might
11436 be using a libc version different from the one the system administrator
11437 used to build the system-wide locale data.
11439 Fortunately, unprivileged users can also install their own locale data
11440 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
11441 @code{GUIX_LOCPATH} and locale packages}).
11443 Still, it is best if the system-wide locale data at
11444 @file{/run/current-system/locale} is built for all the libc versions
11445 actually in use on the system, so that all the programs can access
11446 it---this is especially crucial on a multi-user system. To do that, the
11447 administrator can specify several libc packages in the
11448 @code{locale-libcs} field of @code{operating-system}:
11451 (use-package-modules base)
11455 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
11458 This example would lead to a system containing locale definitions for
11459 both libc 2.21 and the current version of libc in
11460 @file{/run/current-system/locale}.
11466 @cindex system services
11467 An important part of preparing an @code{operating-system} declaration is
11468 listing @dfn{system services} and their configuration (@pxref{Using the
11469 Configuration System}). System services are typically daemons launched
11470 when the system boots, or other actions needed at that time---e.g.,
11471 configuring network access.
11473 Guix has a broad definition of ``service'' (@pxref{Service
11474 Composition}), but many services are managed by the GNU@tie{}Shepherd
11475 (@pxref{Shepherd Services}). On a running system, the @command{herd}
11476 command allows you to list the available services, show their status,
11477 start and stop them, or do other specific operations (@pxref{Jump
11478 Start,,, shepherd, The GNU Shepherd Manual}). For example:
11484 The above command, run as @code{root}, lists the currently defined
11485 services. The @command{herd doc} command shows a synopsis of the given
11486 service and its associated actions:
11490 Run libc's name service cache daemon (nscd).
11492 # herd doc nscd action invalidate
11493 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
11496 The @command{start}, @command{stop}, and @command{restart} sub-commands
11497 have the effect you would expect. For instance, the commands below stop
11498 the nscd service and restart the Xorg display server:
11502 Service nscd has been stopped.
11503 # herd restart xorg-server
11504 Service xorg-server has been stopped.
11505 Service xorg-server has been started.
11508 The following sections document the available services, starting with
11509 the core services, that may be used in an @code{operating-system}
11513 * Base Services:: Essential system services.
11514 * Scheduled Job Execution:: The mcron service.
11515 * Log Rotation:: The rottlog service.
11516 * Networking Services:: Network setup, SSH daemon, etc.
11517 * X Window:: Graphical display.
11518 * Printing Services:: Local and remote printer support.
11519 * Desktop Services:: D-Bus and desktop services.
11520 * Sound Services:: ALSA and Pulseaudio services.
11521 * Database Services:: SQL databases, key-value stores, etc.
11522 * Mail Services:: IMAP, POP3, SMTP, and all that.
11523 * Messaging Services:: Messaging services.
11524 * Telephony Services:: Telephony services.
11525 * Monitoring Services:: Monitoring services.
11526 * Kerberos Services:: Kerberos services.
11527 * LDAP Services:: LDAP services.
11528 * Web Services:: Web servers.
11529 * Certificate Services:: TLS certificates via Let's Encrypt.
11530 * DNS Services:: DNS daemons.
11531 * VPN Services:: VPN daemons.
11532 * Network File System:: NFS related services.
11533 * Continuous Integration:: The Cuirass service.
11534 * Power Management Services:: Extending battery life.
11535 * Audio Services:: The MPD.
11536 * Virtualization Services:: Virtualization services.
11537 * Version Control Services:: Providing remote access to Git repositories.
11538 * Game Services:: Game servers.
11539 * Miscellaneous Services:: Other services.
11542 @node Base Services
11543 @subsection Base Services
11545 The @code{(gnu services base)} module provides definitions for the basic
11546 services that one expects from the system. The services exported by
11547 this module are listed below.
11549 @defvr {Scheme Variable} %base-services
11550 This variable contains a list of basic services (@pxref{Service Types
11551 and Services}, for more information on service objects) one would
11552 expect from the system: a login service (mingetty) on each tty, syslogd,
11553 the libc name service cache daemon (nscd), the udev device manager, and
11556 This is the default value of the @code{services} field of
11557 @code{operating-system} declarations. Usually, when customizing a
11558 system, you will want to append services to @code{%base-services}, like
11562 (append (list (service avahi-service-type)
11563 (service openssh-service-type))
11568 @defvr {Scheme Variable} special-files-service-type
11569 This is the service that sets up ``special files'' such as
11570 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
11572 The value associated with @code{special-files-service-type} services
11573 must be a list of tuples where the first element is the ``special file''
11574 and the second element is its target. By default it is:
11576 @cindex @file{/bin/sh}
11577 @cindex @file{sh}, in @file{/bin}
11579 `(("/bin/sh" ,(file-append @var{bash} "/bin/sh")))
11582 @cindex @file{/usr/bin/env}
11583 @cindex @file{env}, in @file{/usr/bin}
11584 If you want to add, say, @code{/usr/bin/env} to your system, you can
11588 `(("/bin/sh" ,(file-append @var{bash} "/bin/sh"))
11589 ("/usr/bin/env" ,(file-append @var{coreutils} "/bin/env")))
11592 Since this is part of @code{%base-services}, you can use
11593 @code{modify-services} to customize the set of special files
11594 (@pxref{Service Reference, @code{modify-services}}). But the simple way
11595 to add a special file is @i{via} the @code{extra-special-file} procedure
11599 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
11600 Use @var{target} as the ``special file'' @var{file}.
11602 For example, adding the following lines to the @code{services} field of
11603 your operating system declaration leads to a @file{/usr/bin/env}
11607 (extra-special-file "/usr/bin/env"
11608 (file-append coreutils "/bin/env"))
11612 @deffn {Scheme Procedure} host-name-service @var{name}
11613 Return a service that sets the host name to @var{name}.
11616 @deffn {Scheme Procedure} login-service @var{config}
11617 Return a service to run login according to @var{config}, a
11618 @code{<login-configuration>} object, which specifies the message of the day,
11619 among other things.
11622 @deftp {Data Type} login-configuration
11623 This is the data type representing the configuration of login.
11628 @cindex message of the day
11629 A file-like object containing the ``message of the day''.
11631 @item @code{allow-empty-passwords?} (default: @code{#t})
11632 Allow empty passwords by default so that first-time users can log in when
11633 the 'root' account has just been created.
11638 @deffn {Scheme Procedure} mingetty-service @var{config}
11639 Return a service to run mingetty according to @var{config}, a
11640 @code{<mingetty-configuration>} object, which specifies the tty to run, among
11644 @deftp {Data Type} mingetty-configuration
11645 This is the data type representing the configuration of Mingetty, which
11646 provides the default implementation of virtual console log-in.
11651 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
11653 @item @code{auto-login} (default: @code{#f})
11654 When true, this field must be a string denoting the user name under
11655 which the system automatically logs in. When it is @code{#f}, a
11656 user name and password must be entered to log in.
11658 @item @code{login-program} (default: @code{#f})
11659 This must be either @code{#f}, in which case the default log-in program
11660 is used (@command{login} from the Shadow tool suite), or a gexp denoting
11661 the name of the log-in program.
11663 @item @code{login-pause?} (default: @code{#f})
11664 When set to @code{#t} in conjunction with @var{auto-login}, the user
11665 will have to press a key before the log-in shell is launched.
11667 @item @code{mingetty} (default: @var{mingetty})
11668 The Mingetty package to use.
11673 @deffn {Scheme Procedure} agetty-service @var{config}
11674 Return a service to run agetty according to @var{config}, an
11675 @code{<agetty-configuration>} object, which specifies the tty to run,
11676 among other things.
11679 @deftp {Data Type} agetty-configuration
11680 This is the data type representing the configuration of agetty, which
11681 implements virtual and serial console log-in. See the @code{agetty(8)}
11682 man page for more information.
11687 The name of the console this agetty runs on, as a string---e.g.,
11688 @code{"ttyS0"}. This argument is optional, it will default to
11689 a reasonable default serial port used by the kernel Linux.
11691 For this, if there is a value for an option @code{agetty.tty} in the kernel
11692 command line, agetty will extract the device name of the serial port
11693 from it and use that.
11695 If not and if there is a value for an option @code{console} with a tty in
11696 the Linux command line, agetty will extract the device name of the
11697 serial port from it and use that.
11699 In both cases, agetty will leave the other serial device settings
11700 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
11703 @item @code{baud-rate} (default: @code{#f})
11704 A string containing a comma-separated list of one or more baud rates, in
11707 @item @code{term} (default: @code{#f})
11708 A string containing the value used for the @code{TERM} environment
11711 @item @code{eight-bits?} (default: @code{#f})
11712 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
11715 @item @code{auto-login} (default: @code{#f})
11716 When passed a login name, as a string, the specified user will be logged
11717 in automatically without prompting for their login name or password.
11719 @item @code{no-reset?} (default: @code{#f})
11720 When @code{#t}, don't reset terminal cflags (control modes).
11722 @item @code{host} (default: @code{#f})
11723 This accepts a string containing the "login_host", which will be written
11724 into the @file{/var/run/utmpx} file.
11726 @item @code{remote?} (default: @code{#f})
11727 When set to @code{#t} in conjunction with @var{host}, this will add an
11728 @code{-r} fakehost option to the command line of the login program
11729 specified in @var{login-program}.
11731 @item @code{flow-control?} (default: @code{#f})
11732 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
11734 @item @code{no-issue?} (default: @code{#f})
11735 When set to @code{#t}, the contents of the @file{/etc/issue} file will
11736 not be displayed before presenting the login prompt.
11738 @item @code{init-string} (default: @code{#f})
11739 This accepts a string that will be sent to the tty or modem before
11740 sending anything else. It can be used to initialize a modem.
11742 @item @code{no-clear?} (default: @code{#f})
11743 When set to @code{#t}, agetty will not clear the screen before showing
11746 @item @code{login-program} (default: (file-append shadow "/bin/login"))
11747 This must be either a gexp denoting the name of a log-in program, or
11748 unset, in which case the default value is the @command{login} from the
11751 @item @code{local-line} (default: @code{#f})
11752 Control the CLOCAL line flag. This accepts one of three symbols as
11753 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
11754 the default value chosen by agetty is @code{'auto}.
11756 @item @code{extract-baud?} (default: @code{#f})
11757 When set to @code{#t}, instruct agetty to try to extract the baud rate
11758 from the status messages produced by certain types of modems.
11760 @item @code{skip-login?} (default: @code{#f})
11761 When set to @code{#t}, do not prompt the user for a login name. This
11762 can be used with @var{login-program} field to use non-standard login
11765 @item @code{no-newline?} (default: @code{#f})
11766 When set to @code{#t}, do not print a newline before printing the
11767 @file{/etc/issue} file.
11769 @c Is this dangerous only when used with login-program, or always?
11770 @item @code{login-options} (default: @code{#f})
11771 This option accepts a string containing options that are passed to the
11772 login program. When used with the @var{login-program}, be aware that a
11773 malicious user could try to enter a login name containing embedded
11774 options that could be parsed by the login program.
11776 @item @code{login-pause} (default: @code{#f})
11777 When set to @code{#t}, wait for any key before showing the login prompt.
11778 This can be used in conjunction with @var{auto-login} to save memory by
11779 lazily spawning shells.
11781 @item @code{chroot} (default: @code{#f})
11782 Change root to the specified directory. This option accepts a directory
11785 @item @code{hangup?} (default: @code{#f})
11786 Use the Linux system call @code{vhangup} to do a virtual hangup of the
11787 specified terminal.
11789 @item @code{keep-baud?} (default: @code{#f})
11790 When set to @code{#t}, try to keep the existing baud rate. The baud
11791 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
11794 @item @code{timeout} (default: @code{#f})
11795 When set to an integer value, terminate if no user name could be read
11796 within @var{timeout} seconds.
11798 @item @code{detect-case?} (default: @code{#f})
11799 When set to @code{#t}, turn on support for detecting an uppercase-only
11800 terminal. This setting will detect a login name containing only
11801 uppercase letters as indicating an uppercase-only terminal and turn on
11802 some upper-to-lower case conversions. Note that this will not support
11803 Unicode characters.
11805 @item @code{wait-cr?} (default: @code{#f})
11806 When set to @code{#t}, wait for the user or modem to send a
11807 carriage-return or linefeed character before displaying
11808 @file{/etc/issue} or login prompt. This is typically used with the
11809 @var{init-string} option.
11811 @item @code{no-hints?} (default: @code{#f})
11812 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
11815 @item @code{no-hostname?} (default: @code{#f})
11816 By default, the hostname is printed. When this option is set to
11817 @code{#t}, no hostname will be shown at all.
11819 @item @code{long-hostname?} (default: @code{#f})
11820 By default, the hostname is only printed until the first dot. When this
11821 option is set to @code{#t}, the fully qualified hostname by
11822 @code{gethostname} or @code{getaddrinfo} is shown.
11824 @item @code{erase-characters} (default: @code{#f})
11825 This option accepts a string of additional characters that should be
11826 interpreted as backspace when the user types their login name.
11828 @item @code{kill-characters} (default: @code{#f})
11829 This option accepts a string that should be interpreted to mean "ignore
11830 all previous characters" (also called a "kill" character) when the user
11831 types their login name.
11833 @item @code{chdir} (default: @code{#f})
11834 This option accepts, as a string, a directory path that will be changed
11837 @item @code{delay} (default: @code{#f})
11838 This options accepts, as an integer, the number of seconds to sleep
11839 before opening the tty and displaying the login prompt.
11841 @item @code{nice} (default: @code{#f})
11842 This option accepts, as an integer, the nice value with which to run the
11843 @command{login} program.
11845 @item @code{extra-options} (default: @code{'()})
11846 This option provides an "escape hatch" for the user to provide arbitrary
11847 command-line arguments to @command{agetty} as a list of strings.
11852 @deffn {Scheme Procedure} kmscon-service-type @var{config}
11853 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
11854 according to @var{config}, a @code{<kmscon-configuration>} object, which
11855 specifies the tty to run, among other things.
11858 @deftp {Data Type} kmscon-configuration
11859 This is the data type representing the configuration of Kmscon, which
11860 implements virtual console log-in.
11864 @item @code{virtual-terminal}
11865 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
11867 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
11868 A gexp denoting the name of the log-in program. The default log-in program is
11869 @command{login} from the Shadow tool suite.
11871 @item @code{login-arguments} (default: @code{'("-p")})
11872 A list of arguments to pass to @command{login}.
11874 @item @code{auto-login} (default: @code{#f})
11875 When passed a login name, as a string, the specified user will be logged
11876 in automatically without prompting for their login name or password.
11878 @item @code{hardware-acceleration?} (default: #f)
11879 Whether to use hardware acceleration.
11881 @item @code{kmscon} (default: @var{kmscon})
11882 The Kmscon package to use.
11887 @cindex name service cache daemon
11889 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
11890 [#:name-services '()]
11891 Return a service that runs the libc name service cache daemon (nscd) with the
11892 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
11893 Service Switch}, for an example.
11895 For convenience, the Shepherd service for nscd provides the following actions:
11899 @cindex cache invalidation, nscd
11900 @cindex nscd, cache invalidation
11901 This invalidate the given cache. For instance, running:
11904 herd invalidate nscd hosts
11908 invalidates the host name lookup cache of nscd.
11911 Running @command{herd statistics nscd} displays information about nscd usage
11917 @defvr {Scheme Variable} %nscd-default-configuration
11918 This is the default @code{<nscd-configuration>} value (see below) used
11919 by @code{nscd-service}. It uses the caches defined by
11920 @var{%nscd-default-caches}; see below.
11923 @deftp {Data Type} nscd-configuration
11924 This is the data type representing the name service cache daemon (nscd)
11929 @item @code{name-services} (default: @code{'()})
11930 List of packages denoting @dfn{name services} that must be visible to
11931 the nscd---e.g., @code{(list @var{nss-mdns})}.
11933 @item @code{glibc} (default: @var{glibc})
11934 Package object denoting the GNU C Library providing the @command{nscd}
11937 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
11938 Name of the nscd log file. This is where debugging output goes when
11939 @code{debug-level} is strictly positive.
11941 @item @code{debug-level} (default: @code{0})
11942 Integer denoting the debugging levels. Higher numbers mean that more
11943 debugging output is logged.
11945 @item @code{caches} (default: @var{%nscd-default-caches})
11946 List of @code{<nscd-cache>} objects denoting things to be cached; see
11952 @deftp {Data Type} nscd-cache
11953 Data type representing a cache database of nscd and its parameters.
11957 @item @code{database}
11958 This is a symbol representing the name of the database to be cached.
11959 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
11960 @code{services}, which designate the corresponding NSS database
11961 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
11963 @item @code{positive-time-to-live}
11964 @itemx @code{negative-time-to-live} (default: @code{20})
11965 A number representing the number of seconds during which a positive or
11966 negative lookup result remains in cache.
11968 @item @code{check-files?} (default: @code{#t})
11969 Whether to check for updates of the files corresponding to
11972 For instance, when @var{database} is @code{hosts}, setting this flag
11973 instructs nscd to check for updates in @file{/etc/hosts} and to take
11976 @item @code{persistent?} (default: @code{#t})
11977 Whether the cache should be stored persistently on disk.
11979 @item @code{shared?} (default: @code{#t})
11980 Whether the cache should be shared among users.
11982 @item @code{max-database-size} (default: 32@tie{}MiB)
11983 Maximum size in bytes of the database cache.
11985 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
11986 @c settings, so leave them out.
11991 @defvr {Scheme Variable} %nscd-default-caches
11992 List of @code{<nscd-cache>} objects used by default by
11993 @code{nscd-configuration} (see above).
11995 It enables persistent and aggressive caching of service and host name
11996 lookups. The latter provides better host name lookup performance,
11997 resilience in the face of unreliable name servers, and also better
11998 privacy---often the result of host name lookups is in local cache, so
11999 external name servers do not even need to be queried.
12002 @anchor{syslog-configuration-type}
12005 @deftp {Data Type} syslog-configuration
12006 This data type represents the configuration of the syslog daemon.
12009 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12010 The syslog daemon to use.
12012 @item @code{config-file} (default: @code{%default-syslog.conf})
12013 The syslog configuration file to use.
12018 @anchor{syslog-service}
12020 @deffn {Scheme Procedure} syslog-service @var{config}
12021 Return a service that runs a syslog daemon according to @var{config}.
12023 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12024 information on the configuration file syntax.
12027 @defvr {Scheme Variable} guix-service-type
12028 This is the type of the service that runs the build daemon,
12029 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12030 @code{guix-configuration} record as described below.
12033 @anchor{guix-configuration-type}
12034 @deftp {Data Type} guix-configuration
12035 This data type represents the configuration of the Guix build daemon.
12036 @xref{Invoking guix-daemon}, for more information.
12039 @item @code{guix} (default: @var{guix})
12040 The Guix package to use.
12042 @item @code{build-group} (default: @code{"guixbuild"})
12043 Name of the group for build user accounts.
12045 @item @code{build-accounts} (default: @code{10})
12046 Number of build user accounts to create.
12048 @item @code{authorize-key?} (default: @code{#t})
12049 @cindex substitutes, authorization thereof
12050 Whether to authorize the substitute keys listed in
12051 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12052 (@pxref{Substitutes}).
12054 @vindex %default-authorized-guix-keys
12055 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12056 The list of authorized key files for archive imports, as a list of
12057 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12058 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12060 @item @code{use-substitutes?} (default: @code{#t})
12061 Whether to use substitutes.
12063 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12064 The list of URLs where to look for substitutes by default.
12066 @item @code{max-silent-time} (default: @code{0})
12067 @itemx @code{timeout} (default: @code{0})
12068 The number of seconds of silence and the number of seconds of activity,
12069 respectively, after which a build process times out. A value of zero
12070 disables the timeout.
12072 @item @code{log-compression} (default: @code{'bzip2})
12073 The type of compression used for build logs---one of @code{gzip},
12074 @code{bzip2}, or @code{none}.
12076 @item @code{extra-options} (default: @code{'()})
12077 List of extra command-line options for @command{guix-daemon}.
12079 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12080 File where @command{guix-daemon}'s standard output and standard error
12083 @item @code{http-proxy} (default: @code{#f})
12084 The HTTP proxy used for downloading fixed-output derivations and
12087 @item @code{tmpdir} (default: @code{#f})
12088 A directory path where the @command{guix-daemon} will perform builds.
12093 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12094 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12095 udev rules can be provided as a list of files through the @var{rules}
12096 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12097 @code{(gnu services base)} simplify the creation of such rule files.
12100 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12101 Return a udev-rule file named @var{file-name} containing the rules
12102 defined by the @var{contents} literal.
12104 In the following example, a rule for a USB device is defined to be
12105 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12106 upon detecting a USB device with a given product identifier.
12109 (define %example-udev-rule
12111 "90-usb-thing.rules"
12112 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12113 "ATTR@{product@}==\"Example\", "
12114 "RUN+=\"/path/to/script\"")))
12117 The @command{herd rules udev} command, as root, returns the name of the
12118 directory containing all the active udev rules.
12121 Here we show how the default @var{udev-service} can be extended with it.
12127 (modify-services %desktop-services
12128 (udev-service-type config =>
12129 (udev-configuration (inherit config)
12130 (rules (append (udev-configuration-rules config)
12131 (list %example-udev-rule))))))))
12134 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12135 Return a udev file named @var{file-name} containing the rules defined
12136 within @var{file}, a file-like object.
12138 The following example showcases how we can use an existing rule file.
12141 (use-modules (guix download) ;for url-fetch
12142 (guix packages) ;for origin
12145 (define %android-udev-rules
12147 "51-android-udev.rules"
12148 (let ((version "20170910"))
12151 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12152 "android-udev-rules/" version "/51-android.rules"))
12154 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12158 Additionally, Guix package definitions can be included in @var{rules} in
12159 order to extend the udev rules with the definitions found under their
12160 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12161 @var{file->udev-rule} example, we could have used the
12162 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12163 packages android)} module.
12165 The following example shows how to use the @var{android-udev-rules}
12166 package so that the Android tool @command{adb} can detect devices
12167 without root privileges. It also details how to create the
12168 @code{adbusers} group, which is required for the proper functioning of
12169 the rules defined within the @var{android-udev-rules} package. To
12170 create such a group, we must define it both as part of the
12171 @var{supplementary-groups} of our @var{user-account} declaration, as
12172 well as in the @var{groups} field of the @var{operating-system} record.
12175 (use-modules (gnu packages android) ;for android-udev-rules
12176 (gnu system shadow) ;for user-group
12181 (users (cons (user-acount
12183 (supplementary-groups
12184 '("adbusers" ;for adb
12185 "wheel" "netdev" "audio" "video"))
12188 (groups (cons (user-group (system? #t) (name "adbusers"))
12194 (modify-services %desktop-services
12197 (udev-configuration (inherit config)
12198 (rules (cons android-udev-rules
12199 (udev-configuration-rules config))))))))
12202 @defvr {Scheme Variable} urandom-seed-service-type
12203 Save some entropy in @var{%random-seed-file} to seed @file{/dev/urandom}
12204 when rebooting. It also tries to seed @file{/dev/urandom} from
12205 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12209 @defvr {Scheme Variable} %random-seed-file
12210 This is the name of the file where some random bytes are saved by
12211 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12212 It defaults to @file{/var/lib/random-seed}.
12217 @defvr {Scheme Variable} gpm-service-type
12218 This is the type of the service that runs GPM, the @dfn{general-purpose
12219 mouse daemon}, which provides mouse support to the Linux console. GPM
12220 allows users to use the mouse in the console, notably to select, copy,
12223 The value for services of this type must be a @code{gpm-configuration}
12224 (see below). This service is not part of @code{%base-services}.
12227 @deftp {Data Type} gpm-configuration
12228 Data type representing the configuration of GPM.
12231 @item @code{options} (default: @code{%default-gpm-options})
12232 Command-line options passed to @command{gpm}. The default set of
12233 options instruct @command{gpm} to listen to mouse events on
12234 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12237 @item @code{gpm} (default: @code{gpm})
12238 The GPM package to use.
12243 @anchor{guix-publish-service-type}
12244 @deffn {Scheme Variable} guix-publish-service-type
12245 This is the service type for @command{guix publish} (@pxref{Invoking
12246 guix publish}). Its value must be a @code{guix-publish-configuration}
12247 object, as described below.
12249 This assumes that @file{/etc/guix} already contains a signing key pair as
12250 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12251 archive}). If that is not the case, the service will fail to start.
12254 @deftp {Data Type} guix-publish-configuration
12255 Data type representing the configuration of the @code{guix publish}
12259 @item @code{guix} (default: @code{guix})
12260 The Guix package to use.
12262 @item @code{port} (default: @code{80})
12263 The TCP port to listen for connections.
12265 @item @code{host} (default: @code{"localhost"})
12266 The host (and thus, network interface) to listen to. Use
12267 @code{"0.0.0.0"} to listen on all the network interfaces.
12269 @item @code{compression} (default: @code{'(("gzip" 3))})
12270 This is a list of compression method/level tuple used when compressing
12271 substitutes. For example, to compress all substitutes with @emph{both} lzip
12272 at level 7 and gzip at level 9, write:
12275 '(("lzip" 7) ("gzip" 9))
12278 Level 9 achieves the best compression ratio at the expense of increased CPU
12279 usage, whereas level 1 achieves fast compression.
12281 An empty list disables compression altogether.
12283 @item @code{nar-path} (default: @code{"nar"})
12284 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
12285 publish, @code{--nar-path}}, for details.
12287 @item @code{cache} (default: @code{#f})
12288 When it is @code{#f}, disable caching and instead generate archives on
12289 demand. Otherwise, this should be the name of a directory---e.g.,
12290 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
12291 archives and meta-data ready to be sent. @xref{Invoking guix publish,
12292 @option{--cache}}, for more information on the tradeoffs involved.
12294 @item @code{workers} (default: @code{#f})
12295 When it is an integer, this is the number of worker threads used for
12296 caching; when @code{#f}, the number of processors is used.
12297 @xref{Invoking guix publish, @option{--workers}}, for more information.
12299 @item @code{ttl} (default: @code{#f})
12300 When it is an integer, this denotes the @dfn{time-to-live} in seconds
12301 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
12302 for more information.
12306 @anchor{rngd-service}
12307 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
12308 [#:device "/dev/hwrng"]
12309 Return a service that runs the @command{rngd} program from @var{rng-tools}
12310 to add @var{device} to the kernel's entropy pool. The service will fail if
12311 @var{device} does not exist.
12314 @anchor{pam-limits-service}
12315 @cindex session limits
12320 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
12322 Return a service that installs a configuration file for the
12323 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
12324 @code{pam_limits} module}. The procedure optionally takes a list of
12325 @code{pam-limits-entry} values, which can be used to specify
12326 @code{ulimit} limits and nice priority limits to user sessions.
12328 The following limits definition sets two hard and soft limits for all
12329 login sessions of users in the @code{realtime} group:
12332 (pam-limits-service
12334 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
12335 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
12338 The first entry increases the maximum realtime priority for
12339 non-privileged processes; the second entry lifts any restriction of the
12340 maximum address space that can be locked in memory. These settings are
12341 commonly used for real-time audio systems.
12344 @node Scheduled Job Execution
12345 @subsection Scheduled Job Execution
12349 @cindex scheduling jobs
12350 The @code{(gnu services mcron)} module provides an interface to
12351 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
12352 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
12353 Unix @command{cron} daemon; the main difference is that it is
12354 implemented in Guile Scheme, which provides a lot of flexibility when
12355 specifying the scheduling of jobs and their actions.
12357 The example below defines an operating system that runs the
12358 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
12359 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
12360 well as the @command{mkid} command on behalf of an unprivileged user
12361 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
12362 gexps to introduce job definitions that are passed to mcron
12363 (@pxref{G-Expressions}).
12366 (use-modules (guix) (gnu) (gnu services mcron))
12367 (use-package-modules base idutils)
12369 (define updatedb-job
12370 ;; Run 'updatedb' at 3AM every day. Here we write the
12371 ;; job's action as a Scheme procedure.
12372 #~(job '(next-hour '(3))
12374 (execl (string-append #$findutils "/bin/updatedb")
12376 "--prunepaths=/tmp /var/tmp /gnu/store"))))
12378 (define garbage-collector-job
12379 ;; Collect garbage 5 minutes after midnight every day.
12380 ;; The job's action is a shell command.
12381 #~(job "5 0 * * *" ;Vixie cron syntax
12384 (define idutils-job
12385 ;; Update the index database as user "charlie" at 12:15PM
12386 ;; and 19:15PM. This runs from the user's home directory.
12387 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
12388 (string-append #$idutils "/bin/mkid src")
12393 (services (cons (service mcron-service-type
12394 (mcron-configuration
12395 (jobs (list garbage-collector-job
12401 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
12402 for more information on mcron job specifications. Below is the
12403 reference of the mcron service.
12405 On a running system, you can use the @code{schedule} action of the service to
12406 visualize the mcron jobs that will be executed next:
12409 # herd schedule mcron
12413 The example above lists the next five tasks that will be executed, but you can
12414 also specify the number of tasks to display:
12417 # herd schedule mcron 10
12420 @defvr {Scheme Variable} mcron-service-type
12421 This is the type of the @code{mcron} service, whose value is an
12422 @code{mcron-configuration} object.
12424 This service type can be the target of a service extension that provides
12425 it additional job specifications (@pxref{Service Composition}). In
12426 other words, it is possible to define services that provide additional
12430 @deftp {Data Type} mcron-configuration
12431 Data type representing the configuration of mcron.
12434 @item @code{mcron} (default: @var{mcron})
12435 The mcron package to use.
12438 This is a list of gexps (@pxref{G-Expressions}), where each gexp
12439 corresponds to an mcron job specification (@pxref{Syntax, mcron job
12440 specifications,, mcron, GNU@tie{}mcron}).
12446 @subsection Log Rotation
12449 @cindex log rotation
12451 Log files such as those found in @file{/var/log} tend to grow endlessly,
12452 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
12453 their contents in separate files, possibly compressed. The @code{(gnu
12454 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
12455 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
12457 The example below defines an operating system that provides log rotation
12458 with the default settings, for commonly encountered log files.
12461 (use-modules (guix) (gnu))
12462 (use-service-modules admin mcron)
12463 (use-package-modules base idutils)
12467 (services (cons (service rottlog-service-type)
12471 @defvr {Scheme Variable} rottlog-service-type
12472 This is the type of the Rottlog service, whose value is a
12473 @code{rottlog-configuration} object.
12475 Other services can extend this one with new @code{log-rotation} objects
12476 (see below), thereby augmenting the set of files to be rotated.
12478 This service type can define mcron jobs (@pxref{Scheduled Job
12479 Execution}) to run the rottlog service.
12482 @deftp {Data Type} rottlog-configuration
12483 Data type representing the configuration of rottlog.
12486 @item @code{rottlog} (default: @code{rottlog})
12487 The Rottlog package to use.
12489 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
12490 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
12491 rottlog, GNU Rot[t]log Manual}).
12493 @item @code{rotations} (default: @code{%default-rotations})
12494 A list of @code{log-rotation} objects as defined below.
12497 This is a list of gexps where each gexp corresponds to an mcron job
12498 specification (@pxref{Scheduled Job Execution}).
12502 @deftp {Data Type} log-rotation
12503 Data type representing the rotation of a group of log files.
12505 Taking an example from the Rottlog manual (@pxref{Period Related File
12506 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
12512 (files '("/var/log/apache/*"))
12513 (options '("storedir apache-archives"
12519 The list of fields is as follows:
12522 @item @code{frequency} (default: @code{'weekly})
12523 The log rotation frequency, a symbol.
12526 The list of files or file glob patterns to rotate.
12528 @item @code{options} (default: @code{'()})
12529 The list of rottlog options for this rotation (@pxref{Configuration
12530 parameters,,, rottlog, GNU Rot[t]lg Manual}).
12532 @item @code{post-rotate} (default: @code{#f})
12533 Either @code{#f} or a gexp to execute once the rotation has completed.
12537 @defvr {Scheme Variable} %default-rotations
12538 Specifies weekly rotation of @var{%rotated-files} and
12539 a couple of other files.
12542 @defvr {Scheme Variable} %rotated-files
12543 The list of syslog-controlled files to be rotated. By default it is:
12544 @code{'("/var/log/messages" "/var/log/secure")}.
12547 @node Networking Services
12548 @subsection Networking Services
12550 The @code{(gnu services networking)} module provides services to configure
12551 the network interface.
12553 @cindex DHCP, networking service
12554 @defvr {Scheme Variable} dhcp-client-service-type
12555 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
12556 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
12557 is the DHCP client package to use, @code{isc-dhcp} by default.
12560 @deffn {Scheme Procedure} dhcpd-service-type
12561 This type defines a service that runs a DHCP daemon. To create a
12562 service of this type, you must supply a @code{<dhcpd-configuration>}.
12566 (service dhcpd-service-type
12567 (dhcpd-configuration
12568 (config-file (local-file "my-dhcpd.conf"))
12569 (interfaces '("enp0s25"))))
12573 @deftp {Data Type} dhcpd-configuration
12575 @item @code{package} (default: @code{isc-dhcp})
12576 The package that provides the DHCP daemon. This package is expected to
12577 provide the daemon at @file{sbin/dhcpd} relative to its output
12578 directory. The default package is the
12579 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
12580 @item @code{config-file} (default: @code{#f})
12581 The configuration file to use. This is required. It will be passed to
12582 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
12583 object (@pxref{G-Expressions, file-like objects}). See @code{man
12584 dhcpd.conf} for details on the configuration file syntax.
12585 @item @code{version} (default: @code{"4"})
12586 The DHCP version to use. The ISC DHCP server supports the values ``4'',
12587 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
12588 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
12590 @item @code{run-directory} (default: @code{"/run/dhcpd"})
12591 The run directory to use. At service activation time, this directory
12592 will be created if it does not exist.
12593 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
12594 The PID file to use. This corresponds to the @code{-pf} option of
12595 @code{dhcpd}. See @code{man dhcpd} for details.
12596 @item @code{interfaces} (default: @code{'()})
12597 The names of the network interfaces on which dhcpd should listen for
12598 broadcasts. If this list is not empty, then its elements (which must be
12599 strings) will be appended to the @code{dhcpd} invocation when starting
12600 the daemon. It may not be necessary to explicitly specify any
12601 interfaces here; see @code{man dhcpd} for details.
12605 @defvr {Scheme Variable} static-networking-service-type
12606 This is the type for statically-configured network interfaces.
12607 @c TODO Document <static-networking> data structures.
12610 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
12611 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
12612 [#:requirement @code{'(udev)}]
12613 Return a service that starts @var{interface} with address @var{ip}. If
12614 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
12615 it must be a string specifying the default network gateway. @var{requirement}
12616 can be used to declare a dependency on another service before configuring the
12619 This procedure can be called several times, one for each network
12620 interface of interest. Behind the scenes what it does is extend
12621 @code{static-networking-service-type} with additional network interfaces
12627 (static-networking-service "eno1" "192.168.1.82"
12628 #:gateway "192.168.1.2"
12629 #:name-servers '("192.168.1.2"))
12636 @cindex network management
12637 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
12638 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
12639 management daemon that aims to simplify wired and wireless networking.
12641 This service adds the @var{wicd} package to the global profile, providing
12642 several commands to interact with the daemon and configure networking:
12643 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
12644 and @command{wicd-curses} user interfaces.
12647 @cindex ModemManager
12649 @defvr {Scheme Variable} modem-manager-service-type
12650 This is the service type for the
12651 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
12652 service. The value for this service type is a
12653 @code{modem-manager-configuration} record.
12655 This service is part of @code{%desktop-services} (@pxref{Desktop
12659 @deftp {Data Type} modem-manager-configuration
12660 Data type representing the configuration of ModemManager.
12663 @item @code{modem-manager} (default: @code{modem-manager})
12664 The ModemManager package to use.
12669 @cindex USB_ModeSwitch
12670 @cindex Modeswitching
12672 @defvr {Scheme Variable} usb-modeswitch-service-type
12673 This is the service type for the
12674 @uref{http://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
12675 value for this service type is a @code{usb-modeswitch-configuration} record.
12677 When plugged in, some USB modems (and other USB devices) initially present
12678 themselves as a read-only storage medium and not as a modem. They need to be
12679 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
12680 installs udev rules to automatically modeswitch these devices when they are
12683 This service is part of @code{%desktop-services} (@pxref{Desktop
12687 @deftp {Data Type} usb-modeswitch-configuration
12688 Data type representing the configuration of USB_ModeSwitch.
12691 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
12692 The USB_ModeSwitch package providing the binaries for modeswitching.
12694 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
12695 The package providing the device data and udev rules file used by
12698 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
12699 Which config file to use for the USB_ModeSwitch dispatcher. By default the
12700 config file shipped with USB_ModeSwitch is used which disables logging to
12701 @file{/var/log} among other default settings. If set to @code{#f}, no config
12707 @cindex NetworkManager
12709 @defvr {Scheme Variable} network-manager-service-type
12710 This is the service type for the
12711 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
12712 service. The value for this service type is a
12713 @code{network-manager-configuration} record.
12715 This service is part of @code{%desktop-services} (@pxref{Desktop
12719 @deftp {Data Type} network-manager-configuration
12720 Data type representing the configuration of NetworkManager.
12723 @item @code{network-manager} (default: @code{network-manager})
12724 The NetworkManager package to use.
12726 @item @code{dns} (default: @code{"default"})
12727 Processing mode for DNS, which affects how NetworkManager uses the
12728 @code{resolv.conf} configuration file.
12732 NetworkManager will update @code{resolv.conf} to reflect the nameservers
12733 provided by currently active connections.
12736 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
12737 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
12738 then update @code{resolv.conf} to point to the local nameserver.
12740 With this setting, you can share your network connection. For example when
12741 you want to share your network connection to another laptop @i{via} an
12742 Ethernet cable, you can open @command{nm-connection-editor} and configure the
12743 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
12744 and reestablish the connection (or reboot).
12746 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
12747 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
12748 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
12749 browser on your host system, or connect to the VM @i{via} SSH
12750 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
12751 host-to-guest connection, run this command once:
12754 nmcli connection add type tun \
12755 connection.interface-name tap0 \
12756 tun.mode tap tun.owner $(id -u) \
12757 ipv4.method shared \
12758 ipv4.addresses 172.28.112.1/24
12761 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
12762 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
12763 @command{qemu-system-...}.
12766 NetworkManager will not modify @code{resolv.conf}.
12769 @item @code{vpn-plugins} (default: @code{'()})
12770 This is the list of available plugins for virtual private networks
12771 (VPNs). An example of this is the @code{network-manager-openvpn}
12772 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
12778 @deffn {Scheme Variable} connman-service-type
12779 This is the service type to run @url{https://01.org/connman,Connman},
12780 a network connection manager.
12782 Its value must be an
12783 @code{connman-configuration} record as in this example:
12786 (service connman-service-type
12787 (connman-configuration
12788 (disable-vpn? #t)))
12791 See below for details about @code{connman-configuration}.
12794 @deftp {Data Type} connman-configuration
12795 Data Type representing the configuration of connman.
12798 @item @code{connman} (default: @var{connman})
12799 The connman package to use.
12801 @item @code{disable-vpn?} (default: @code{#f})
12802 When true, disable connman's vpn plugin.
12806 @cindex WPA Supplicant
12807 @defvr {Scheme Variable} wpa-supplicant-service-type
12808 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
12809 supplicant}, an authentication daemon required to authenticate against
12810 encrypted WiFi or ethernet networks.
12813 @deftp {Data Type} wpa-supplicant-configuration
12814 Data type representing the configuration of WPA Supplicant.
12816 It takes the following parameters:
12819 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
12820 The WPA Supplicant package to use.
12822 @item @code{dbus?} (default: @code{#t})
12823 Whether to listen for requests on D-Bus.
12825 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
12826 Where to store the PID file.
12828 @item @code{interface} (default: @code{#f})
12829 If this is set, it must specify the name of a network interface that
12830 WPA supplicant will control.
12832 @item @code{config-file} (default: @code{#f})
12833 Optional configuration file to use.
12835 @item @code{extra-options} (default: @code{'()})
12836 List of additional command-line arguments to pass to the daemon.
12841 @defvr {Scheme Variable} iptables-service-type
12842 This is the service type to set up an iptables configuration. iptables is a
12843 packet filtering framework supported by the Linux kernel. This service
12844 supports configuring iptables for both IPv4 and IPv6. A simple example
12845 configuration rejecting all incoming connections except those to the ssh port
12849 (service iptables-service-type
12850 (iptables-configuration
12851 (ipv4-rules (plain-file "iptables.rules" "*filter
12855 -A INPUT -p tcp --dport 22 -j ACCEPT
12856 -A INPUT -j REJECT --reject-with icmp-port-unreachable
12859 (ipv6-rules (plain-file "ip6tables.rules" "*filter
12863 -A INPUT -p tcp --dport 22 -j ACCEPT
12864 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
12870 @deftp {Data Type} iptables-configuration
12871 The data type representing the configuration of iptables.
12874 @item @code{iptables} (default: @code{iptables})
12875 The iptables package that provides @code{iptables-restore} and
12876 @code{ip6tables-restore}.
12877 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
12878 The iptables rules to use. It will be passed to @code{iptables-restore}.
12879 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
12881 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
12882 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
12883 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
12888 @cindex NTP (Network Time Protocol), service
12889 @cindex real time clock
12890 @defvr {Scheme Variable} ntp-service-type
12891 This is the type of the service running the @uref{http://www.ntp.org,
12892 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
12893 system clock synchronized with that of the specified NTP servers.
12895 The value of this service is an @code{ntpd-configuration} object, as described
12899 @deftp {Data Type} ntp-configuration
12900 This is the data type for the NTP service configuration.
12903 @item @code{servers} (default: @code{%ntp-servers})
12904 This is the list of servers (host names) with which @command{ntpd} will be
12907 @item @code{allow-large-adjustment?} (default: @code{#f})
12908 This determines whether @command{ntpd} is allowed to make an initial
12909 adjustment of more than 1,000 seconds.
12911 @item @code{ntp} (default: @code{ntp})
12912 The NTP package to use.
12916 @defvr {Scheme Variable} %ntp-servers
12917 List of host names used as the default NTP servers. These are servers of the
12918 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
12922 @deffn {Scheme Procedure} openntpd-service-type
12923 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
12924 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
12925 clock synchronized with that of the given servers.
12929 openntpd-service-type
12930 (openntpd-configuration
12931 (listen-on '("127.0.0.1" "::1"))
12932 (sensor '("udcf0 correction 70000"))
12933 (constraint-from '("www.gnu.org"))
12934 (constraints-from '("https://www.google.com/"))
12935 (allow-large-adjustment? #t)))
12940 @deftp {Data Type} openntpd-configuration
12942 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
12943 The openntpd executable to use.
12944 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
12945 A list of local IP addresses or hostnames the ntpd daemon should listen on.
12946 @item @code{query-from} (default: @code{'()})
12947 A list of local IP address the ntpd daemon should use for outgoing queries.
12948 @item @code{sensor} (default: @code{'()})
12949 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
12950 will listen to each sensor that actually exists and ignore non-existent ones.
12951 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
12953 @item @code{server} (default: @var{%ntp-servers})
12954 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
12955 @item @code{servers} (default: @code{'()})
12956 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
12957 @item @code{constraint-from} (default: @code{'()})
12958 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
12959 This time information is not used for precision but acts as an authenticated
12960 constraint, thereby reducing the impact of unauthenticated NTP
12961 man-in-the-middle attacks.
12962 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
12964 @item @code{constraints-from} (default: @code{'()})
12965 As with constraint from, specify a list of URLs, IP addresses or hostnames of
12966 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
12967 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
12968 @item @code{allow-large-adjustment?} (default: @code{#f})
12969 Determines if @code{ntpd} is allowed to make an initial adjustment of more
12975 @deffn {Scheme variable} inetd-service-type
12976 This service runs the @command{inetd} (@pxref{inetd invocation,,,
12977 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
12978 connections on internet sockets, and lazily starts the specified server
12979 program when a connection is made on one of these sockets.
12981 The value of this service is an @code{inetd-configuration} object. The
12982 following example configures the @command{inetd} daemon to provide the
12983 built-in @command{echo} service, as well as an smtp service which
12984 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
12985 gateway @code{hostname}:
12990 (inetd-configuration
12994 (socket-type 'stream)
13001 (socket-type 'stream)
13005 (program (file-append openssh "/bin/ssh"))
13007 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13008 "-W" "smtp-server:25" "user@@hostname")))))
13011 See below for more details about @code{inetd-configuration}.
13014 @deftp {Data Type} inetd-configuration
13015 Data type representing the configuration of @command{inetd}.
13018 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13019 The @command{inetd} executable to use.
13021 @item @code{entries} (default: @code{'()})
13022 A list of @command{inetd} service entries. Each entry should be created
13023 by the @code{inetd-entry} constructor.
13027 @deftp {Data Type} inetd-entry
13028 Data type representing an entry in the @command{inetd} configuration.
13029 Each entry corresponds to a socket where @command{inetd} will listen for
13033 @item @code{node} (default: @code{#f})
13034 Optional string, a comma-separated list of local addresses
13035 @command{inetd} should use when listening for this service.
13036 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13037 description of all options.
13039 A string, the name must correspond to an entry in @code{/etc/services}.
13040 @item @code{socket-type}
13041 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13043 @item @code{protocol}
13044 A string, must correspond to an entry in @code{/etc/protocols}.
13045 @item @code{wait?} (default: @code{#t})
13046 Whether @command{inetd} should wait for the server to exit before
13047 listening to new service requests.
13049 A string containing the user (and, optionally, group) name of the user
13050 as whom the server should run. The group name can be specified in a
13051 suffix, separated by a colon or period, i.e.@: @code{"user"},
13052 @code{"user:group"} or @code{"user.group"}.
13053 @item @code{program} (default: @code{"internal"})
13054 The server program which will serve the requests, or @code{"internal"}
13055 if @command{inetd} should use a built-in service.
13056 @item @code{arguments} (default: @code{'()})
13057 A list strings or file-like objects, which are the server program's
13058 arguments, starting with the zeroth argument, i.e.@: the name of the
13059 program itself. For @command{inetd}'s internal services, this entry
13060 must be @code{'()} or @code{'("internal")}.
13063 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13064 detailed discussion of each configuration field.
13068 @defvr {Scheme Variable} tor-service-type
13069 This is the type for a service that runs the @uref{https://torproject.org,
13070 Tor} anonymous networking daemon. The service is configured using a
13071 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
13072 @code{tor} unprivileged user, which is a member of the @code{tor} group.
13076 @deftp {Data Type} tor-configuration
13078 @item @code{tor} (default: @code{tor})
13079 The package that provides the Tor daemon. This package is expected to provide
13080 the daemon at @file{bin/tor} relative to its output directory. The default
13081 package is the @uref{https://www.torproject.org, Tor Project's}
13084 @item @code{config-file} (default: @code{(plain-file "empty" "")})
13085 The configuration file to use. It will be appended to a default configuration
13086 file, and the final configuration file will be passed to @code{tor} via its
13087 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
13088 file-like objects}). See @code{man tor} for details on the configuration file
13091 @item @code{hidden-services} (default: @code{'()})
13092 The list of @code{<hidden-service>} records to use. For any hidden service
13093 you include in this list, appropriate configuration to enable the hidden
13094 service will be automatically added to the default configuration file. You
13095 may conveniently create @code{<hidden-service>} records using the
13096 @code{tor-hidden-service} procedure described below.
13098 @item @code{socks-socket-type} (default: @code{'tcp})
13099 The default socket type that Tor should use for its SOCKS socket. This must
13100 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
13101 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
13102 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
13103 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13106 If you want to customize the SOCKS socket in more detail, leave
13107 @code{socks-socket-type} at its default value of @code{'tcp} and use
13108 @code{config-file} to override the default by providing your own
13109 @code{SocksPort} option.
13113 @cindex hidden service
13114 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13115 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13116 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13119 '((22 "127.0.0.1:22")
13120 (80 "127.0.0.1:8080"))
13123 In this example, port 22 of the hidden service is mapped to local port 22, and
13124 port 80 is mapped to local port 8080.
13126 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13127 the @file{hostname} file contains the @code{.onion} host name for the hidden
13130 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13131 project's documentation} for more information.
13134 The @code{(gnu services rsync)} module provides the following services:
13136 You might want an rsync daemon if you have files that you want available
13137 so anyone (or just yourself) can download existing files or upload new
13140 @deffn {Scheme Variable} rsync-service-type
13141 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13142 The value for this service type is a
13143 @command{rsync-configuration} record as in this example:
13146 (service rsync-service-type)
13149 See below for details about @code{rsync-configuration}.
13152 @deftp {Data Type} rsync-configuration
13153 Data type representing the configuration for @code{rsync-service}.
13156 @item @code{package} (default: @var{rsync})
13157 @code{rsync} package to use.
13159 @item @code{port-number} (default: @code{873})
13160 TCP port on which @command{rsync} listens for incoming connections. If port
13161 is less than @code{1024} @command{rsync} needs to be started as the
13162 @code{root} user and group.
13164 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
13165 Name of the file where @command{rsync} writes its PID.
13167 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
13168 Name of the file where @command{rsync} writes its lock file.
13170 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
13171 Name of the file where @command{rsync} writes its log file.
13173 @item @code{use-chroot?} (default: @var{#t})
13174 Whether to use chroot for @command{rsync} shared directory.
13176 @item @code{share-path} (default: @file{/srv/rsync})
13177 Location of the @command{rsync} shared directory.
13179 @item @code{share-comment} (default: @code{"Rsync share"})
13180 Comment of the @command{rsync} shared directory.
13182 @item @code{read-only?} (default: @var{#f})
13183 Read-write permissions to shared directory.
13185 @item @code{timeout} (default: @code{300})
13186 I/O timeout in seconds.
13188 @item @code{user} (default: @var{"root"})
13189 Owner of the @code{rsync} process.
13191 @item @code{group} (default: @var{"root"})
13192 Group of the @code{rsync} process.
13194 @item @code{uid} (default: @var{"rsyncd"})
13195 User name or user ID that file transfers to and from that module should take
13196 place as when the daemon was run as @code{root}.
13198 @item @code{gid} (default: @var{"rsyncd"})
13199 Group name or group ID that will be used when accessing the module.
13204 Furthermore, @code{(gnu services ssh)} provides the following services.
13208 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
13209 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
13210 [#:allow-empty-passwords? #f] [#:root-login? #f] @
13211 [#:syslog-output? #t] [#:x11-forwarding? #t] @
13212 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
13213 [#:public-key-authentication? #t] [#:initialize? #t]
13214 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
13215 @var{host-key} must designate a file containing the host key, and readable
13218 When @var{daemonic?} is true, @command{lshd} will detach from the
13219 controlling terminal and log its output to syslogd, unless one sets
13220 @var{syslog-output?} to false. Obviously, it also makes lsh-service
13221 depend on existence of syslogd service. When @var{pid-file?} is true,
13222 @command{lshd} writes its PID to the file called @var{pid-file}.
13224 When @var{initialize?} is true, automatically create the seed and host key
13225 upon service activation if they do not exist yet. This may take long and
13226 require interaction.
13228 When @var{initialize?} is false, it is up to the user to initialize the
13229 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
13230 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
13231 basics,,, lsh, LSH Manual}).
13233 When @var{interfaces} is empty, lshd listens for connections on all the
13234 network interfaces; otherwise, @var{interfaces} must be a list of host names
13237 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
13238 passwords, and @var{root-login?} specifies whether to accept log-ins as
13241 The other options should be self-descriptive.
13246 @deffn {Scheme Variable} openssh-service-type
13247 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
13248 shell daemon, @command{sshd}. Its value must be an
13249 @code{openssh-configuration} record as in this example:
13252 (service openssh-service-type
13253 (openssh-configuration
13254 (x11-forwarding? #t)
13255 (permit-root-login 'without-password)
13257 `(("alice" ,(local-file "alice.pub"))
13258 ("bob" ,(local-file "bob.pub"))))))
13261 See below for details about @code{openssh-configuration}.
13263 This service can be extended with extra authorized keys, as in this
13267 (service-extension openssh-service-type
13268 (const `(("charlie"
13269 ,(local-file "charlie.pub")))))
13273 @deftp {Data Type} openssh-configuration
13274 This is the configuration record for OpenSSH's @command{sshd}.
13277 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
13278 Name of the file where @command{sshd} writes its PID.
13280 @item @code{port-number} (default: @code{22})
13281 TCP port on which @command{sshd} listens for incoming connections.
13283 @item @code{permit-root-login} (default: @code{#f})
13284 This field determines whether and when to allow logins as root. If
13285 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
13286 If it's the symbol @code{'without-password}, then root logins are
13287 permitted but not with password-based authentication.
13289 @item @code{allow-empty-passwords?} (default: @code{#f})
13290 When true, users with empty passwords may log in. When false, they may
13293 @item @code{password-authentication?} (default: @code{#t})
13294 When true, users may log in with their password. When false, they have
13295 other authentication methods.
13297 @item @code{public-key-authentication?} (default: @code{#t})
13298 When true, users may log in using public key authentication. When
13299 false, users have to use other authentication method.
13301 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
13302 This is used only by protocol version 2.
13304 @item @code{x11-forwarding?} (default: @code{#f})
13305 When true, forwarding of X11 graphical client connections is
13306 enabled---in other words, @command{ssh} options @option{-X} and
13307 @option{-Y} will work.
13309 @item @code{allow-agent-forwarding?} (default: @code{#t})
13310 Whether to allow agent forwarding.
13312 @item @code{allow-tcp-forwarding?} (default: @code{#t})
13313 Whether to allow TCP forwarding.
13315 @item @code{gateway-ports?} (default: @code{#f})
13316 Whether to allow gateway ports.
13318 @item @code{challenge-response-authentication?} (default: @code{#f})
13319 Specifies whether challenge response authentication is allowed (e.g.@: via
13322 @item @code{use-pam?} (default: @code{#t})
13323 Enables the Pluggable Authentication Module interface. If set to
13324 @code{#t}, this will enable PAM authentication using
13325 @code{challenge-response-authentication?} and
13326 @code{password-authentication?}, in addition to PAM account and session
13327 module processing for all authentication types.
13329 Because PAM challenge response authentication usually serves an
13330 equivalent role to password authentication, you should disable either
13331 @code{challenge-response-authentication?} or
13332 @code{password-authentication?}.
13334 @item @code{print-last-log?} (default: @code{#t})
13335 Specifies whether @command{sshd} should print the date and time of the
13336 last user login when a user logs in interactively.
13338 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
13339 Configures external subsystems (e.g.@: file transfer daemon).
13341 This is a list of two-element lists, each of which containing the
13342 subsystem name and a command (with optional arguments) to execute upon
13345 The command @command{internal-sftp} implements an in-process SFTP
13346 server. Alternately, one can specify the @command{sftp-server} command:
13348 (service openssh-service-type
13349 (openssh-configuration
13351 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
13354 @item @code{accepted-environment} (default: @code{'()})
13355 List of strings describing which environment variables may be exported.
13357 Each string gets on its own line. See the @code{AcceptEnv} option in
13358 @code{man sshd_config}.
13360 This example allows ssh-clients to export the @code{COLORTERM} variable.
13361 It is set by terminal emulators, which support colors. You can use it in
13362 your shell's ressource file to enable colors for the prompt and commands
13363 if this variable is set.
13366 (service openssh-service-type
13367 (openssh-configuration
13368 (accepted-environment '("COLORTERM"))))
13371 @item @code{authorized-keys} (default: @code{'()})
13372 @cindex authorized keys, SSH
13373 @cindex SSH authorized keys
13374 This is the list of authorized keys. Each element of the list is a user
13375 name followed by one or more file-like objects that represent SSH public
13379 (openssh-configuration
13381 `(("rekado" ,(local-file "rekado.pub"))
13382 ("chris" ,(local-file "chris.pub"))
13383 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
13387 registers the specified public keys for user accounts @code{rekado},
13388 @code{chris}, and @code{root}.
13390 Additional authorized keys can be specified @i{via}
13391 @code{service-extension}.
13393 Note that this does @emph{not} interfere with the use of
13394 @file{~/.ssh/authorized_keys}.
13396 @item @code{log-level} (default: @code{'info})
13397 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
13398 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
13399 page for @file{sshd_config} for the full list of level names.
13401 @item @code{extra-content} (default: @code{""})
13402 This field can be used to append arbitrary text to the configuration file. It
13403 is especially useful for elaborate configurations that cannot be expressed
13404 otherwise. This configuration, for example, would generally disable root
13405 logins, but permit them from one specific IP address:
13408 (openssh-configuration
13410 Match Address 192.168.0.1
13411 PermitRootLogin yes"))
13417 @deffn {Scheme Procedure} dropbear-service [@var{config}]
13418 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
13419 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
13422 For example, to specify a Dropbear service listening on port 1234, add
13423 this call to the operating system's @code{services} field:
13426 (dropbear-service (dropbear-configuration
13427 (port-number 1234)))
13431 @deftp {Data Type} dropbear-configuration
13432 This data type represents the configuration of a Dropbear SSH daemon.
13435 @item @code{dropbear} (default: @var{dropbear})
13436 The Dropbear package to use.
13438 @item @code{port-number} (default: 22)
13439 The TCP port where the daemon waits for incoming connections.
13441 @item @code{syslog-output?} (default: @code{#t})
13442 Whether to enable syslog output.
13444 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
13445 File name of the daemon's PID file.
13447 @item @code{root-login?} (default: @code{#f})
13448 Whether to allow @code{root} logins.
13450 @item @code{allow-empty-passwords?} (default: @code{#f})
13451 Whether to allow empty passwords.
13453 @item @code{password-authentication?} (default: @code{#t})
13454 Whether to enable password-based authentication.
13458 @defvr {Scheme Variable} %facebook-host-aliases
13459 This variable contains a string for use in @file{/etc/hosts}
13460 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
13461 line contains a entry that maps a known server name of the Facebook
13462 on-line service---e.g., @code{www.facebook.com}---to the local
13463 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
13465 This variable is typically used in the @code{hosts-file} field of an
13466 @code{operating-system} declaration (@pxref{operating-system Reference,
13467 @file{/etc/hosts}}):
13470 (use-modules (gnu) (guix))
13473 (host-name "mymachine")
13476 ;; Create a /etc/hosts file with aliases for "localhost"
13477 ;; and "mymachine", as well as for Facebook servers.
13478 (plain-file "hosts"
13479 (string-append (local-host-aliases host-name)
13480 %facebook-host-aliases))))
13483 This mechanism can prevent programs running locally, such as Web
13484 browsers, from accessing Facebook.
13487 The @code{(gnu services avahi)} provides the following definition.
13489 @defvr {Scheme Variable} avahi-service-type
13490 This is the service that runs @command{avahi-daemon}, a system-wide
13491 mDNS/DNS-SD responder that allows for service discovery and
13492 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
13493 Its value must be a @code{zero-configuration} record---see below.
13495 This service extends the name service cache daemon (nscd) so that it can
13496 resolve @code{.local} host names using
13497 @uref{http://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
13498 Service Switch}, for information on host name resolution.
13500 Additionally, add the @var{avahi} package to the system profile so that
13501 commands such as @command{avahi-browse} are directly usable.
13504 @deftp {Data Type} avahi-configuration
13505 Data type representation the configuration for Avahi.
13509 @item @code{host-name} (default: @code{#f})
13510 If different from @code{#f}, use that as the host name to
13511 publish for this machine; otherwise, use the machine's actual host name.
13513 @item @code{publish?} (default: @code{#t})
13514 When true, allow host names and services to be published (broadcast) over the
13517 @item @code{publish-workstation?} (default: @code{#t})
13518 When true, @command{avahi-daemon} publishes the machine's host name and IP
13519 address via mDNS on the local network. To view the host names published on
13520 your local network, you can run:
13523 avahi-browse _workstation._tcp
13526 @item @code{wide-area?} (default: @code{#f})
13527 When true, DNS-SD over unicast DNS is enabled.
13529 @item @code{ipv4?} (default: @code{#t})
13530 @itemx @code{ipv6?} (default: @code{#t})
13531 These fields determine whether to use IPv4/IPv6 sockets.
13533 @item @code{domains-to-browse} (default: @code{'()})
13534 This is a list of domains to browse.
13538 @deffn {Scheme Variable} openvswitch-service-type
13539 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
13540 service, whose value should be an @code{openvswitch-configuration}
13544 @deftp {Data Type} openvswitch-configuration
13545 Data type representing the configuration of Open vSwitch, a multilayer
13546 virtual switch which is designed to enable massive network automation
13547 through programmatic extension.
13550 @item @code{package} (default: @var{openvswitch})
13551 Package object of the Open vSwitch.
13557 @subsection X Window
13560 @cindex X Window System
13561 @cindex login manager
13562 Support for the X Window graphical display system---specifically
13563 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
13564 there is no @code{xorg-service} procedure. Instead, the X server is
13565 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
13568 @cindex GNOME, login manager
13569 GDM of course allows users to log in into window managers and desktop
13570 environments other than GNOME; for those using GNOME, GDM is required for
13571 features such as automatic screen locking.
13573 @cindex window manager
13574 To use X11, you must install at least one @dfn{window manager}---for
13575 example the @code{windowmaker} or @code{openbox} packages---preferably
13576 by adding it to the @code{packages} field of your operating system
13577 definition (@pxref{operating-system Reference, system-wide packages}).
13579 @defvr {Scheme Variable} gdm-service-type
13580 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
13581 Desktop Manager} (GDM), a program that manages graphical display servers and
13582 handles graphical user logins. Its value must be a @code{gdm-configuration}
13585 @cindex session types (X11)
13586 @cindex X11 session types
13587 GDM looks for @dfn{session types} described by the @file{.desktop} files in
13588 @file{/run/current-system/profile/share/xsessions} and allows users to choose
13589 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
13590 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
13591 set of packages automatically makes them available at the log-in screen.
13593 In addition, @file{~/.xsession} files are honored. When available,
13594 @file{~/.xsession} must be an executable that starts a window manager
13595 and/or other X clients.
13598 @deftp {Data Type} gdm-configuration
13600 @item @code{auto-login?} (default: @code{#f})
13601 @itemx @code{default-user} (default: @code{#f})
13602 When @code{auto-login?} is false, GDM presents a log-in screen.
13604 When @code{auto-login?} is true, GDM logs in directly as
13605 @code{default-user}.
13607 @item @code{gnome-shell-assets} (default: ...)
13608 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
13610 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
13611 Configuration of the Xorg graphical server.
13613 @item @code{xsession} (default: @code{(xinitrc)})
13614 Script to run before starting a X session.
13616 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
13617 File name of the @code{dbus-daemon} executable.
13619 @item @code{gdm} (default: @code{gdm})
13620 The GDM package to use.
13624 @defvr {Scheme Variable} slim-service-type
13625 This is the type for the SLiM graphical login manager for X11.
13627 Like GDM, SLiM looks for session types described by @file{.desktop} files and
13628 allows users to choose a session from the log-in screen using @kbd{F1}. It
13629 also honors @file{~/.xsession} files.
13631 Unlike GDM, SLiM does not spawn the user session on a different VT after
13632 logging in, which means that you can only start one graphical session. If you
13633 want to be able to run multiple graphical sessions at the same time you have
13634 to add multiple SLiM services to your system services. The following example
13635 shows how to replace the default GDM service with two SLiM services on tty7
13639 (use-modules (gnu services)
13640 (gnu services desktop)
13641 (gnu services xorg)
13642 (srfi srfi-1)) ;for 'remove'
13646 (services (cons* (service slim-service-type (slim-configuration
13649 (service slim-service-type (slim-configuration
13652 (remove (lambda (service)
13653 (eq? (service-kind service) gdm-service-type))
13654 %desktop-services))))
13659 @deftp {Data Type} slim-configuration
13660 Data type representing the configuration of @code{slim-service-type}.
13663 @item @code{allow-empty-passwords?} (default: @code{#t})
13664 Whether to allow logins with empty passwords.
13666 @item @code{auto-login?} (default: @code{#f})
13667 @itemx @code{default-user} (default: @code{""})
13668 When @code{auto-login?} is false, SLiM presents a log-in screen.
13670 When @code{auto-login?} is true, SLiM logs in directly as
13671 @code{default-user}.
13673 @item @code{theme} (default: @code{%default-slim-theme})
13674 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
13675 The graphical theme to use and its name.
13677 @item @code{auto-login-session} (default: @code{#f})
13678 If true, this must be the name of the executable to start as the default
13679 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
13681 If false, a session described by one of the available @file{.desktop}
13682 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
13686 You must install at least one window manager in the system profile or in
13687 your user profile. Failing to do that, if @code{auto-login-session} is
13688 false, you will be unable to log in.
13691 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13692 Configuration of the Xorg graphical server.
13694 @item @code{display} (default @code{":0"})
13695 The display on which to start the Xorg graphical server.
13697 @item @code{vt} (default @code{"vt7"})
13698 The VT on which to start the Xorg graphical server.
13700 @item @code{xauth} (default: @code{xauth})
13701 The XAuth package to use.
13703 @item @code{shepherd} (default: @code{shepherd})
13704 The Shepherd package used when invoking @command{halt} and
13707 @item @code{sessreg} (default: @code{sessreg})
13708 The sessreg package used in order to register the session.
13710 @item @code{slim} (default: @code{slim})
13711 The SLiM package to use.
13715 @defvr {Scheme Variable} %default-theme
13716 @defvrx {Scheme Variable} %default-theme-name
13717 The default SLiM theme and its name.
13721 @deftp {Data Type} sddm-configuration
13722 This is the data type representing the sddm service configuration.
13725 @item @code{display-server} (default: "x11")
13726 Select display server to use for the greeter. Valid values are "x11"
13729 @item @code{numlock} (default: "on")
13730 Valid values are "on", "off" or "none".
13732 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
13733 Command to run when halting.
13735 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
13736 Command to run when rebooting.
13738 @item @code{theme} (default "maldives")
13739 Theme to use. Default themes provided by SDDM are "elarun" or "maldives".
13741 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
13742 Directory to look for themes.
13744 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
13745 Directory to look for faces.
13747 @item @code{default-path} (default "/run/current-system/profile/bin")
13748 Default PATH to use.
13750 @item @code{minimum-uid} (default: 1000)
13751 Minimum UID displayed in SDDM and allowed for log-in.
13753 @item @code{maximum-uid} (default: 2000)
13754 Maximum UID to display in SDDM.
13756 @item @code{remember-last-user?} (default #t)
13757 Remember last user.
13759 @item @code{remember-last-session?} (default #t)
13760 Remember last session.
13762 @item @code{hide-users} (default "")
13763 Usernames to hide from SDDM greeter.
13765 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
13766 Users with shells listed will be hidden from the SDDM greeter.
13768 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
13769 Script to run before starting a wayland session.
13771 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
13772 Directory to look for desktop files starting wayland sessions.
13774 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13775 Configuration of the Xorg graphical server.
13777 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
13780 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
13783 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
13784 Script to run after starting xorg-server.
13786 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
13787 Script to run before stopping xorg-server.
13789 @item @code{xsession-command} (default: @code{xinitrc})
13790 Script to run before starting a X session.
13792 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
13793 Directory to look for desktop files starting X sessions.
13795 @item @code{minimum-vt} (default: 7)
13798 @item @code{auto-login-user} (default "")
13799 User to use for auto-login.
13801 @item @code{auto-login-session} (default "")
13802 Desktop file to use for auto-login.
13804 @item @code{relogin?} (default #f)
13805 Relogin after logout.
13810 @cindex login manager
13812 @deffn {Scheme Procedure} sddm-service config
13813 Return a service that spawns the SDDM graphical login manager for config of
13814 type @code{<sddm-configuration>}.
13817 (sddm-service (sddm-configuration
13818 (auto-login-user "Alice")
13819 (auto-login-session "xfce.desktop")))
13823 @cindex Xorg, configuration
13824 @deftp {Data Type} xorg-configuration
13825 This data type represents the configuration of the Xorg graphical display
13826 server. Note that there is not Xorg service; instead, the X server is started
13827 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
13828 of these display managers aggregates an @code{xorg-configuration} record.
13831 @item @code{modules} (default: @code{%default-xorg-modules})
13832 This is a list of @dfn{module packages} loaded by the Xorg
13833 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
13835 @item @code{fonts} (default: @code{%default-xorg-fonts})
13836 This is a list of font directories to add to the server's @dfn{font path}.
13838 @item @code{drivers} (default: @code{'()})
13839 This must be either the empty list, in which case Xorg chooses a graphics
13840 driver automatically, or a list of driver names that will be tried in this
13841 order---e.g., @code{("modesetting" "vesa")}.
13843 @item @code{resolutions} (default: @code{'()})
13844 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
13845 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
13848 @cindex keyboard layout, for Xorg
13849 @cindex keymap, for Xorg
13850 @item @code{keyboard-layout} (default: @code{#f})
13851 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
13852 English (``qwerty'') for a 105-key PC keyboard.
13854 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
13855 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
13856 information on how to specify the keyboard layout.
13858 @item @code{extra-config} (default: @code{'()})
13859 This is a list of strings or objects appended to the configuration file. It
13860 is used to pass extra text to be added verbatim to the configuration file.
13862 @item @code{server} (default: @code{xorg-server})
13863 This is the package providing the Xorg server.
13865 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
13866 This is the list of command-line arguments to pass to the X server. The
13867 default is @code{-nolisten tcp}.
13871 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
13872 [@var{login-manager-service-type}]
13873 Tell the log-in manager (of type @var{login-manager-service-type}) to use
13874 @var{config}, an @code{<xorg-configuration>} record.
13876 Since the Xorg configuration is embedded in the log-in manager's
13877 configuration---e.g., @code{gdm-configuration}---this procedure provides a
13878 shorthand to set the Xorg configuration.
13881 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
13882 Return a @code{startx} script in which the modules, fonts, etc. specified
13883 in @var{config}, are available. The result should be used in place of
13886 Usually the X server is started by a login manager.
13890 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
13891 Add @var{package}, a package for a screen locker or screen saver whose
13892 command is @var{program}, to the set of setuid programs and add a PAM entry
13893 for it. For example:
13896 (screen-locker-service xlockmore "xlock")
13899 makes the good ol' XlockMore usable.
13903 @node Printing Services
13904 @subsection Printing Services
13906 @cindex printer support with CUPS
13907 The @code{(gnu services cups)} module provides a Guix service definition
13908 for the CUPS printing service. To add printer support to a Guix
13909 system, add a @code{cups-service} to the operating system definition:
13911 @deffn {Scheme Variable} cups-service-type
13912 The service type for the CUPS print server. Its value should be a valid
13913 CUPS configuration (see below). To use the default settings, simply
13916 (service cups-service-type)
13920 The CUPS configuration controls the basic things about your CUPS
13921 installation: what interfaces it listens on, what to do if a print job
13922 fails, how much logging to do, and so on. To actually add a printer,
13923 you have to visit the @url{http://localhost:631} URL, or use a tool such
13924 as GNOME's printer configuration services. By default, configuring a
13925 CUPS service will generate a self-signed certificate if needed, for
13926 secure connections to the print server.
13928 Suppose you want to enable the Web interface of CUPS and also add
13929 support for Epson printers @i{via} the @code{escpr} package and for HP
13930 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
13931 like this (you need to use the @code{(gnu packages cups)} module):
13934 (service cups-service-type
13935 (cups-configuration
13936 (web-interface? #t)
13938 (list cups-filters escpr hplip-minimal))))
13941 Note: If you wish to use the Qt5 based GUI which comes with the hplip
13942 package then it is suggested that you install the @code{hplip} package,
13943 either in your OS configuration file or as your user.
13945 The available configuration parameters follow. Each parameter
13946 definition is preceded by its type; for example, @samp{string-list foo}
13947 indicates that the @code{foo} parameter should be specified as a list of
13948 strings. There is also a way to specify the configuration as a string,
13949 if you have an old @code{cupsd.conf} file that you want to port over
13950 from some other system; see the end for more details.
13952 @c The following documentation was initially generated by
13953 @c (generate-documentation) in (gnu services cups). Manually maintained
13954 @c documentation is better, so we shouldn't hesitate to edit below as
13955 @c needed. However if the change you want to make to this documentation
13956 @c can be done in an automated way, it's probably easier to change
13957 @c (generate-documentation) than to make it below and have to deal with
13958 @c the churn as CUPS updates.
13961 Available @code{cups-configuration} fields are:
13963 @deftypevr {@code{cups-configuration} parameter} package cups
13967 @deftypevr {@code{cups-configuration} parameter} package-list extensions
13968 Drivers and other extensions to the CUPS package.
13971 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
13972 Configuration of where to write logs, what directories to use for print
13973 spools, and related privileged configuration parameters.
13975 Available @code{files-configuration} fields are:
13977 @deftypevr {@code{files-configuration} parameter} log-location access-log
13978 Defines the access log filename. Specifying a blank filename disables
13979 access log generation. The value @code{stderr} causes log entries to be
13980 sent to the standard error file when the scheduler is running in the
13981 foreground, or to the system log daemon when run in the background. The
13982 value @code{syslog} causes log entries to be sent to the system log
13983 daemon. The server name may be included in filenames using the string
13984 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
13986 Defaults to @samp{"/var/log/cups/access_log"}.
13989 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
13990 Where CUPS should cache data.
13992 Defaults to @samp{"/var/cache/cups"}.
13995 @deftypevr {@code{files-configuration} parameter} string config-file-perm
13996 Specifies the permissions for all configuration files that the scheduler
13999 Note that the permissions for the printers.conf file are currently
14000 masked to only allow access from the scheduler user (typically root).
14001 This is done because printer device URIs sometimes contain sensitive
14002 authentication information that should not be generally known on the
14003 system. There is no way to disable this security feature.
14005 Defaults to @samp{"0640"}.
14008 @deftypevr {@code{files-configuration} parameter} log-location error-log
14009 Defines the error log filename. Specifying a blank filename disables
14010 error log generation. The value @code{stderr} causes log entries to be
14011 sent to the standard error file when the scheduler is running in the
14012 foreground, or to the system log daemon when run in the background. The
14013 value @code{syslog} causes log entries to be sent to the system log
14014 daemon. The server name may be included in filenames using the string
14015 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
14017 Defaults to @samp{"/var/log/cups/error_log"}.
14020 @deftypevr {@code{files-configuration} parameter} string fatal-errors
14021 Specifies which errors are fatal, causing the scheduler to exit. The
14026 No errors are fatal.
14029 All of the errors below are fatal.
14032 Browsing initialization errors are fatal, for example failed connections
14033 to the DNS-SD daemon.
14036 Configuration file syntax errors are fatal.
14039 Listen or Port errors are fatal, except for IPv6 failures on the
14040 loopback or @code{any} addresses.
14043 Log file creation or write errors are fatal.
14046 Bad startup file permissions are fatal, for example shared TLS
14047 certificate and key files with world-read permissions.
14050 Defaults to @samp{"all -browse"}.
14053 @deftypevr {@code{files-configuration} parameter} boolean file-device?
14054 Specifies whether the file pseudo-device can be used for new printer
14055 queues. The URI @uref{file:///dev/null} is always allowed.
14057 Defaults to @samp{#f}.
14060 @deftypevr {@code{files-configuration} parameter} string group
14061 Specifies the group name or ID that will be used when executing external
14064 Defaults to @samp{"lp"}.
14067 @deftypevr {@code{files-configuration} parameter} string log-file-perm
14068 Specifies the permissions for all log files that the scheduler writes.
14070 Defaults to @samp{"0644"}.
14073 @deftypevr {@code{files-configuration} parameter} log-location page-log
14074 Defines the page log filename. Specifying a blank filename disables
14075 page log generation. The value @code{stderr} causes log entries to be
14076 sent to the standard error file when the scheduler is running in the
14077 foreground, or to the system log daemon when run in the background. The
14078 value @code{syslog} causes log entries to be sent to the system log
14079 daemon. The server name may be included in filenames using the string
14080 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
14082 Defaults to @samp{"/var/log/cups/page_log"}.
14085 @deftypevr {@code{files-configuration} parameter} string remote-root
14086 Specifies the username that is associated with unauthenticated accesses
14087 by clients claiming to be the root user. The default is @code{remroot}.
14089 Defaults to @samp{"remroot"}.
14092 @deftypevr {@code{files-configuration} parameter} file-name request-root
14093 Specifies the directory that contains print jobs and other HTTP request
14096 Defaults to @samp{"/var/spool/cups"}.
14099 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
14100 Specifies the level of security sandboxing that is applied to print
14101 filters, backends, and other child processes of the scheduler; either
14102 @code{relaxed} or @code{strict}. This directive is currently only
14103 used/supported on macOS.
14105 Defaults to @samp{strict}.
14108 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
14109 Specifies the location of TLS certificates and private keys. CUPS will
14110 look for public and private keys in this directory: a @code{.crt} files
14111 for PEM-encoded certificates and corresponding @code{.key} files for
14112 PEM-encoded private keys.
14114 Defaults to @samp{"/etc/cups/ssl"}.
14117 @deftypevr {@code{files-configuration} parameter} file-name server-root
14118 Specifies the directory containing the server configuration files.
14120 Defaults to @samp{"/etc/cups"}.
14123 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
14124 Specifies whether the scheduler calls fsync(2) after writing
14125 configuration or state files.
14127 Defaults to @samp{#f}.
14130 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
14131 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
14134 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
14135 Specifies the directory where temporary files are stored.
14137 Defaults to @samp{"/var/spool/cups/tmp"}.
14140 @deftypevr {@code{files-configuration} parameter} string user
14141 Specifies the user name or ID that is used when running external
14144 Defaults to @samp{"lp"}.
14148 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
14149 Specifies the logging level for the AccessLog file. The @code{config}
14150 level logs when printers and classes are added, deleted, or modified and
14151 when configuration files are accessed or updated. The @code{actions}
14152 level logs when print jobs are submitted, held, released, modified, or
14153 canceled, and any of the conditions for @code{config}. The @code{all}
14154 level logs all requests.
14156 Defaults to @samp{actions}.
14159 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
14160 Specifies whether to purge job history data automatically when it is no
14161 longer required for quotas.
14163 Defaults to @samp{#f}.
14166 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
14167 Specifies which protocols to use for local printer sharing.
14169 Defaults to @samp{dnssd}.
14172 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
14173 Specifies whether the CUPS web interface is advertised.
14175 Defaults to @samp{#f}.
14178 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
14179 Specifies whether shared printers are advertised.
14181 Defaults to @samp{#f}.
14184 @deftypevr {@code{cups-configuration} parameter} string classification
14185 Specifies the security classification of the server. Any valid banner
14186 name can be used, including "classified", "confidential", "secret",
14187 "topsecret", and "unclassified", or the banner can be omitted to disable
14188 secure printing functions.
14190 Defaults to @samp{""}.
14193 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
14194 Specifies whether users may override the classification (cover page) of
14195 individual print jobs using the @code{job-sheets} option.
14197 Defaults to @samp{#f}.
14200 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
14201 Specifies the default type of authentication to use.
14203 Defaults to @samp{Basic}.
14206 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
14207 Specifies whether encryption will be used for authenticated requests.
14209 Defaults to @samp{Required}.
14212 @deftypevr {@code{cups-configuration} parameter} string default-language
14213 Specifies the default language to use for text and web content.
14215 Defaults to @samp{"en"}.
14218 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
14219 Specifies the default paper size for new print queues. @samp{"Auto"}
14220 uses a locale-specific default, while @samp{"None"} specifies there is
14221 no default paper size. Specific size names are typically
14222 @samp{"Letter"} or @samp{"A4"}.
14224 Defaults to @samp{"Auto"}.
14227 @deftypevr {@code{cups-configuration} parameter} string default-policy
14228 Specifies the default access policy to use.
14230 Defaults to @samp{"default"}.
14233 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
14234 Specifies whether local printers are shared by default.
14236 Defaults to @samp{#t}.
14239 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
14240 Specifies the delay for updating of configuration and state files, in
14241 seconds. A value of 0 causes the update to happen as soon as possible,
14242 typically within a few milliseconds.
14244 Defaults to @samp{30}.
14247 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
14248 Specifies what to do when an error occurs. Possible values are
14249 @code{abort-job}, which will discard the failed print job;
14250 @code{retry-job}, which will retry the job at a later time;
14251 @code{retry-this-job}, which retries the failed job immediately; and
14252 @code{stop-printer}, which stops the printer.
14254 Defaults to @samp{stop-printer}.
14257 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
14258 Specifies the maximum cost of filters that are run concurrently, which
14259 can be used to minimize disk, memory, and CPU resource problems. A
14260 limit of 0 disables filter limiting. An average print to a
14261 non-PostScript printer needs a filter limit of about 200. A PostScript
14262 printer needs about half that (100). Setting the limit below these
14263 thresholds will effectively limit the scheduler to printing a single job
14266 Defaults to @samp{0}.
14269 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
14270 Specifies the scheduling priority of filters that are run to print a
14271 job. The nice value ranges from 0, the highest priority, to 19, the
14274 Defaults to @samp{0}.
14277 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
14278 Specifies whether to do reverse lookups on connecting clients. The
14279 @code{double} setting causes @code{cupsd} to verify that the hostname
14280 resolved from the address matches one of the addresses returned for that
14281 hostname. Double lookups also prevent clients with unregistered
14282 addresses from connecting to your server. Only set this option to
14283 @code{#t} or @code{double} if absolutely required.
14285 Defaults to @samp{#f}.
14288 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
14289 Specifies the number of seconds to wait before killing the filters and
14290 backend associated with a canceled or held job.
14292 Defaults to @samp{30}.
14295 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
14296 Specifies the interval between retries of jobs in seconds. This is
14297 typically used for fax queues but can also be used with normal print
14298 queues whose error policy is @code{retry-job} or
14299 @code{retry-current-job}.
14301 Defaults to @samp{30}.
14304 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
14305 Specifies the number of retries that are done for jobs. This is
14306 typically used for fax queues but can also be used with normal print
14307 queues whose error policy is @code{retry-job} or
14308 @code{retry-current-job}.
14310 Defaults to @samp{5}.
14313 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
14314 Specifies whether to support HTTP keep-alive connections.
14316 Defaults to @samp{#t}.
14319 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
14320 Specifies how long an idle client connection remains open, in seconds.
14322 Defaults to @samp{30}.
14325 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
14326 Specifies the maximum size of print files, IPP requests, and HTML form
14327 data. A limit of 0 disables the limit check.
14329 Defaults to @samp{0}.
14332 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
14333 Listens on the specified interfaces for connections. Valid values are
14334 of the form @var{address}:@var{port}, where @var{address} is either an
14335 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
14336 indicate all addresses. Values can also be file names of local UNIX
14337 domain sockets. The Listen directive is similar to the Port directive
14338 but allows you to restrict access to specific interfaces or networks.
14341 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
14342 Specifies the number of pending connections that will be allowed. This
14343 normally only affects very busy servers that have reached the MaxClients
14344 limit, but can also be triggered by large numbers of simultaneous
14345 connections. When the limit is reached, the operating system will
14346 refuse additional connections until the scheduler can accept the pending
14349 Defaults to @samp{128}.
14352 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
14353 Specifies a set of additional access controls.
14355 Available @code{location-access-controls} fields are:
14357 @deftypevr {@code{location-access-controls} parameter} file-name path
14358 Specifies the URI path to which the access control applies.
14361 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
14362 Access controls for all access to this path, in the same format as the
14363 @code{access-controls} of @code{operation-access-control}.
14365 Defaults to @samp{()}.
14368 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
14369 Access controls for method-specific access to this path.
14371 Defaults to @samp{()}.
14373 Available @code{method-access-controls} fields are:
14375 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
14376 If @code{#t}, apply access controls to all methods except the listed
14377 methods. Otherwise apply to only the listed methods.
14379 Defaults to @samp{#f}.
14382 @deftypevr {@code{method-access-controls} parameter} method-list methods
14383 Methods to which this access control applies.
14385 Defaults to @samp{()}.
14388 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
14389 Access control directives, as a list of strings. Each string should be
14390 one directive, such as "Order allow,deny".
14392 Defaults to @samp{()}.
14397 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
14398 Specifies the number of debugging messages that are retained for logging
14399 if an error occurs in a print job. Debug messages are logged regardless
14400 of the LogLevel setting.
14402 Defaults to @samp{100}.
14405 @deftypevr {@code{cups-configuration} parameter} log-level log-level
14406 Specifies the level of logging for the ErrorLog file. The value
14407 @code{none} stops all logging while @code{debug2} logs everything.
14409 Defaults to @samp{info}.
14412 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
14413 Specifies the format of the date and time in the log files. The value
14414 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
14416 Defaults to @samp{standard}.
14419 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
14420 Specifies the maximum number of simultaneous clients that are allowed by
14423 Defaults to @samp{100}.
14426 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
14427 Specifies the maximum number of simultaneous clients that are allowed
14428 from a single address.
14430 Defaults to @samp{100}.
14433 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
14434 Specifies the maximum number of copies that a user can print of each
14437 Defaults to @samp{9999}.
14440 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
14441 Specifies the maximum time a job may remain in the @code{indefinite}
14442 hold state before it is canceled. A value of 0 disables cancellation of
14445 Defaults to @samp{0}.
14448 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
14449 Specifies the maximum number of simultaneous jobs that are allowed. Set
14450 to 0 to allow an unlimited number of jobs.
14452 Defaults to @samp{500}.
14455 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
14456 Specifies the maximum number of simultaneous jobs that are allowed per
14457 printer. A value of 0 allows up to MaxJobs jobs per printer.
14459 Defaults to @samp{0}.
14462 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
14463 Specifies the maximum number of simultaneous jobs that are allowed per
14464 user. A value of 0 allows up to MaxJobs jobs per user.
14466 Defaults to @samp{0}.
14469 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
14470 Specifies the maximum time a job may take to print before it is
14471 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
14473 Defaults to @samp{10800}.
14476 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
14477 Specifies the maximum size of the log files before they are rotated, in
14478 bytes. The value 0 disables log rotation.
14480 Defaults to @samp{1048576}.
14483 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
14484 Specifies the maximum amount of time to allow between files in a
14485 multiple file print job, in seconds.
14487 Defaults to @samp{300}.
14490 @deftypevr {@code{cups-configuration} parameter} string page-log-format
14491 Specifies the format of PageLog lines. Sequences beginning with percent
14492 (@samp{%}) characters are replaced with the corresponding information,
14493 while all other characters are copied literally. The following percent
14494 sequences are recognized:
14498 insert a single percent character
14501 insert the value of the specified IPP attribute
14504 insert the number of copies for the current page
14507 insert the current page number
14510 insert the current date and time in common log format
14516 insert the printer name
14519 insert the username
14522 A value of the empty string disables page logging. The string @code{%p
14523 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
14524 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
14527 Defaults to @samp{""}.
14530 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
14531 Passes the specified environment variable(s) to child processes; a list
14534 Defaults to @samp{()}.
14537 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
14538 Specifies named access control policies.
14540 Available @code{policy-configuration} fields are:
14542 @deftypevr {@code{policy-configuration} parameter} string name
14543 Name of the policy.
14546 @deftypevr {@code{policy-configuration} parameter} string job-private-access
14547 Specifies an access list for a job's private values. @code{@@ACL} maps
14548 to the printer's requesting-user-name-allowed or
14549 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14550 owner. @code{@@SYSTEM} maps to the groups listed for the
14551 @code{system-group} field of the @code{files-config} configuration,
14552 which is reified into the @code{cups-files.conf(5)} file. Other
14553 possible elements of the access list include specific user names, and
14554 @code{@@@var{group}} to indicate members of a specific group. The
14555 access list may also be simply @code{all} or @code{default}.
14557 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14560 @deftypevr {@code{policy-configuration} parameter} string job-private-values
14561 Specifies the list of job values to make private, or @code{all},
14562 @code{default}, or @code{none}.
14564 Defaults to @samp{"job-name job-originating-host-name
14565 job-originating-user-name phone"}.
14568 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
14569 Specifies an access list for a subscription's private values.
14570 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
14571 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14572 owner. @code{@@SYSTEM} maps to the groups listed for the
14573 @code{system-group} field of the @code{files-config} configuration,
14574 which is reified into the @code{cups-files.conf(5)} file. Other
14575 possible elements of the access list include specific user names, and
14576 @code{@@@var{group}} to indicate members of a specific group. The
14577 access list may also be simply @code{all} or @code{default}.
14579 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14582 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
14583 Specifies the list of job values to make private, or @code{all},
14584 @code{default}, or @code{none}.
14586 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
14587 notify-subscriber-user-name notify-user-data"}.
14590 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
14591 Access control by IPP operation.
14593 Defaults to @samp{()}.
14597 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
14598 Specifies whether job files (documents) are preserved after a job is
14599 printed. If a numeric value is specified, job files are preserved for
14600 the indicated number of seconds after printing. Otherwise a boolean
14601 value applies indefinitely.
14603 Defaults to @samp{86400}.
14606 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
14607 Specifies whether the job history is preserved after a job is printed.
14608 If a numeric value is specified, the job history is preserved for the
14609 indicated number of seconds after printing. If @code{#t}, the job
14610 history is preserved until the MaxJobs limit is reached.
14612 Defaults to @samp{#t}.
14615 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
14616 Specifies the amount of time to wait for job completion before
14617 restarting the scheduler.
14619 Defaults to @samp{30}.
14622 @deftypevr {@code{cups-configuration} parameter} string rip-cache
14623 Specifies the maximum amount of memory to use when converting documents
14624 into bitmaps for a printer.
14626 Defaults to @samp{"128m"}.
14629 @deftypevr {@code{cups-configuration} parameter} string server-admin
14630 Specifies the email address of the server administrator.
14632 Defaults to @samp{"root@@localhost.localdomain"}.
14635 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
14636 The ServerAlias directive is used for HTTP Host header validation when
14637 clients connect to the scheduler from external interfaces. Using the
14638 special name @code{*} can expose your system to known browser-based DNS
14639 rebinding attacks, even when accessing sites through a firewall. If the
14640 auto-discovery of alternate names does not work, we recommend listing
14641 each alternate name with a ServerAlias directive instead of using
14644 Defaults to @samp{*}.
14647 @deftypevr {@code{cups-configuration} parameter} string server-name
14648 Specifies the fully-qualified host name of the server.
14650 Defaults to @samp{"localhost"}.
14653 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
14654 Specifies what information is included in the Server header of HTTP
14655 responses. @code{None} disables the Server header. @code{ProductOnly}
14656 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
14657 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
14658 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
14659 the output of the @code{uname} command. @code{Full} reports @code{CUPS
14660 2.0.0 (@var{uname}) IPP/2.0}.
14662 Defaults to @samp{Minimal}.
14665 @deftypevr {@code{cups-configuration} parameter} string set-env
14666 Set the specified environment variable to be passed to child processes.
14668 Defaults to @samp{"variable value"}.
14671 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
14672 Listens on the specified interfaces for encrypted connections. Valid
14673 values are of the form @var{address}:@var{port}, where @var{address} is
14674 either an IPv6 address enclosed in brackets, an IPv4 address, or
14675 @code{*} to indicate all addresses.
14677 Defaults to @samp{()}.
14680 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
14681 Sets encryption options. By default, CUPS only supports encryption
14682 using TLS v1.0 or higher using known secure cipher suites. The
14683 @code{AllowRC4} option enables the 128-bit RC4 cipher suites, which are
14684 required for some older clients that do not implement newer ones. The
14685 @code{AllowSSL3} option enables SSL v3.0, which is required for some
14686 older clients that do not support TLS v1.0.
14688 Defaults to @samp{()}.
14691 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
14692 Specifies whether the scheduler requires clients to strictly adhere to
14693 the IPP specifications.
14695 Defaults to @samp{#f}.
14698 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
14699 Specifies the HTTP request timeout, in seconds.
14701 Defaults to @samp{300}.
14705 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
14706 Specifies whether the web interface is enabled.
14708 Defaults to @samp{#f}.
14711 At this point you're probably thinking ``oh dear, Guix manual, I like
14712 you but you can stop already with the configuration options''. Indeed.
14713 However, one more point: it could be that you have an existing
14714 @code{cupsd.conf} that you want to use. In that case, you can pass an
14715 @code{opaque-cups-configuration} as the configuration of a
14716 @code{cups-service-type}.
14718 Available @code{opaque-cups-configuration} fields are:
14720 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
14724 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
14725 The contents of the @code{cupsd.conf}, as a string.
14728 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
14729 The contents of the @code{cups-files.conf} file, as a string.
14732 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
14733 strings of the same name, you could instantiate a CUPS service like
14737 (service cups-service-type
14738 (opaque-cups-configuration
14739 (cupsd.conf cupsd.conf)
14740 (cups-files.conf cups-files.conf)))
14744 @node Desktop Services
14745 @subsection Desktop Services
14747 The @code{(gnu services desktop)} module provides services that are
14748 usually useful in the context of a ``desktop'' setup---that is, on a
14749 machine running a graphical display server, possibly with graphical user
14750 interfaces, etc. It also defines services that provide specific desktop
14751 environments like GNOME, Xfce or MATE.
14753 To simplify things, the module defines a variable containing the set of
14754 services that users typically expect on a machine with a graphical
14755 environment and networking:
14757 @defvr {Scheme Variable} %desktop-services
14758 This is a list of services that builds upon @code{%base-services} and
14759 adds or adjusts services for a typical ``desktop'' setup.
14761 In particular, it adds a graphical login manager (@pxref{X Window,
14762 @code{gdm-service-type}}), screen lockers, a network management tool
14763 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
14764 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
14765 energy and color management services, the @code{elogind} login and seat
14766 manager, the Polkit privilege service, the GeoClue location service, the
14767 AccountsService daemon that allows authorized users change system passwords,
14768 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
14769 name service switch service configured to be able to use @code{nss-mdns}
14770 (@pxref{Name Service Switch, mDNS}).
14773 The @code{%desktop-services} variable can be used as the @code{services}
14774 field of an @code{operating-system} declaration (@pxref{operating-system
14775 Reference, @code{services}}).
14777 Additionally, the @code{gnome-desktop-service-type},
14778 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
14779 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
14780 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
14781 services like the backlight adjustment helpers and the power management
14782 utilities are added to the system, extending @code{polkit} and @code{dbus}
14783 appropriately, allowing GNOME to operate with elevated privileges on a
14784 limited number of special-purpose system interfaces. Additionally,
14785 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
14786 metapackage to the system profile. Likewise, adding the Xfce service
14787 not only adds the @code{xfce} metapackage to the system profile, but it
14788 also gives the Thunar file manager the ability to open a ``root-mode''
14789 file management window, if the user authenticates using the
14790 administrator's password via the standard polkit graphical interface.
14791 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
14792 appropriately, allowing MATE to operate with elevated privileges on a
14793 limited number of special-purpose system interfaces. Additionally,
14794 adding a service of type @code{mate-desktop-service-type} adds the MATE
14795 metapackage to the system profile. ``Adding Enlightenment'' means that
14796 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
14797 are set as setuid, allowing Enlightenment's screen locker and other
14798 functionality to work as expetected.
14800 The desktop environments in Guix use the Xorg display server by
14801 default. If you'd like to use the newer display server protocol
14802 called Wayland, you need to use the @code{sddm-service} instead of
14803 GDM as the graphical login manager. You should then
14804 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
14805 also try starting GNOME on Wayland manually from a TTY with the
14806 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
14807 gnome-session``. Currently only GNOME has support for Wayland.
14809 @defvr {Scheme Variable} gnome-desktop-service-type
14810 This is the type of the service that adds the @uref{https://www.gnome.org,
14811 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
14812 object (see below.)
14814 This service adds the @code{gnome} package to the system profile, and extends
14815 polkit with the actions from @code{gnome-settings-daemon}.
14818 @deftp {Data Type} gnome-desktop-configuration
14819 Configuration record for the GNOME desktop environment.
14822 @item @code{gnome} (default: @code{gnome})
14823 The GNOME package to use.
14827 @defvr {Scheme Variable} xfce-desktop-service-type
14828 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
14829 desktop environment. Its value is an @code{xfce-desktop-configuration} object
14832 This service adds the @code{xfce} package to the system profile, and
14833 extends polkit with the ability for @code{thunar} to manipulate the file
14834 system as root from within a user session, after the user has authenticated
14835 with the administrator's password.
14838 @deftp {Data Type} xfce-desktop-configuration
14839 Configuration record for the Xfce desktop environment.
14842 @item @code{xfce} (default: @code{xfce})
14843 The Xfce package to use.
14847 @deffn {Scheme Variable} mate-desktop-service-type
14848 This is the type of the service that runs the @uref{https://mate-desktop.org/,
14849 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
14850 object (see below.)
14852 This service adds the @code{mate} package to the system
14853 profile, and extends polkit with the actions from
14854 @code{mate-settings-daemon}.
14857 @deftp {Data Type} mate-desktop-configuration
14858 Configuration record for the MATE desktop environment.
14861 @item @code{mate} (default: @code{mate})
14862 The MATE package to use.
14866 @deffn {Scheme Variable} enlightenment-desktop-service-type
14867 Return a service that adds the @code{enlightenment} package to the system
14868 profile, and extends dbus with actions from @code{efl}.
14871 @deftp {Data Type} enlightenment-desktop-service-configuration
14873 @item @code{enlightenment} (default: @code{enlightenment})
14874 The enlightenment package to use.
14878 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
14879 the default @code{%desktop-services} variable doesn't include any of
14880 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
14881 @code{%desktop-services} in the @code{services} field of your
14882 @code{operating-system}:
14885 (use-modules (gnu))
14886 (use-service-modules desktop)
14889 ;; cons* adds items to the list given as its last argument.
14890 (services (cons* (service gnome-desktop-service-type)
14891 (service xfce-desktop-service)
14892 %desktop-services))
14896 These desktop environments will then be available as options in the
14897 graphical login window.
14899 The actual service definitions included in @code{%desktop-services} and
14900 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
14901 are described below.
14903 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
14904 Return a service that runs the ``system bus'', using @var{dbus}, with
14905 support for @var{services}.
14907 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
14908 facility. Its system bus is used to allow system services to communicate
14909 and to be notified of system-wide events.
14911 @var{services} must be a list of packages that provide an
14912 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
14913 and policy files. For example, to allow avahi-daemon to use the system bus,
14914 @var{services} must be equal to @code{(list avahi)}.
14917 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
14918 Return a service that runs the @code{elogind} login and
14919 seat management daemon. @uref{https://github.com/elogind/elogind,
14920 Elogind} exposes a D-Bus interface that can be used to know which users
14921 are logged in, know what kind of sessions they have open, suspend the
14922 system, inhibit system suspend, reboot the system, and other tasks.
14924 Elogind handles most system-level power events for a computer, for
14925 example suspending the system when a lid is closed, or shutting it down
14926 when the power button is pressed.
14928 The @var{config} keyword argument specifies the configuration for
14929 elogind, and should be the result of an @code{(elogind-configuration
14930 (@var{parameter} @var{value})...)} invocation. Available parameters and
14931 their default values are:
14934 @item kill-user-processes?
14936 @item kill-only-users
14938 @item kill-exclude-users
14940 @item inhibit-delay-max-seconds
14942 @item handle-power-key
14944 @item handle-suspend-key
14946 @item handle-hibernate-key
14948 @item handle-lid-switch
14950 @item handle-lid-switch-docked
14952 @item power-key-ignore-inhibited?
14954 @item suspend-key-ignore-inhibited?
14956 @item hibernate-key-ignore-inhibited?
14958 @item lid-switch-ignore-inhibited?
14960 @item holdoff-timeout-seconds
14964 @item idle-action-seconds
14966 @item runtime-directory-size-percent
14968 @item runtime-directory-size
14972 @item suspend-state
14973 @code{("mem" "standby" "freeze")}
14976 @item hibernate-state
14978 @item hibernate-mode
14979 @code{("platform" "shutdown")}
14980 @item hybrid-sleep-state
14982 @item hybrid-sleep-mode
14983 @code{("suspend" "platform" "shutdown")}
14987 @deffn {Scheme Procedure} accountsservice-service @
14988 [#:accountsservice @var{accountsservice}]
14989 Return a service that runs AccountsService, a system service that can
14990 list available accounts, change their passwords, and so on.
14991 AccountsService integrates with PolicyKit to enable unprivileged users
14992 to acquire the capability to modify their system configuration.
14993 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
14994 accountsservice web site} for more information.
14996 The @var{accountsservice} keyword argument is the @code{accountsservice}
14997 package to expose as a service.
15000 @deffn {Scheme Procedure} polkit-service @
15001 [#:polkit @var{polkit}]
15002 Return a service that runs the
15003 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
15004 management service}, which allows system administrators to grant access to
15005 privileged operations in a structured way. By querying the Polkit service, a
15006 privileged system component can know when it should grant additional
15007 capabilities to ordinary users. For example, an ordinary user can be granted
15008 the capability to suspend the system if the user is logged in locally.
15011 @defvr {Scheme Variable} upower-service-type
15012 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
15013 system-wide monitor for power consumption and battery levels, with the given
15014 configuration settings.
15016 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
15017 notably used by GNOME.
15020 @deftp {Data Type} upower-configuration
15021 Data type representation the configuration for UPower.
15025 @item @code{upower} (default: @var{upower})
15026 Package to use for @code{upower}.
15028 @item @code{watts-up-pro?} (default: @code{#f})
15029 Enable the Watts Up Pro device.
15031 @item @code{poll-batteries?} (default: @code{#t})
15032 Enable polling the kernel for battery level changes.
15034 @item @code{ignore-lid?} (default: @code{#f})
15035 Ignore the lid state, this can be useful if it's incorrect on a device.
15037 @item @code{use-percentage-for-policy?} (default: @code{#f})
15038 Whether battery percentage based policy should be used. The default is to use
15039 the time left, change to @code{#t} to use the percentage.
15041 @item @code{percentage-low} (default: @code{10})
15042 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15043 at which the battery is considered low.
15045 @item @code{percentage-critical} (default: @code{3})
15046 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15047 at which the battery is considered critical.
15049 @item @code{percentage-action} (default: @code{2})
15050 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15051 at which action will be taken.
15053 @item @code{time-low} (default: @code{1200})
15054 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15055 seconds at which the battery is considered low.
15057 @item @code{time-critical} (default: @code{300})
15058 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15059 seconds at which the battery is considered critical.
15061 @item @code{time-action} (default: @code{120})
15062 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15063 seconds at which action will be taken.
15065 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
15066 The action taken when @code{percentage-action} or @code{time-action} is
15067 reached (depending on the configuration of @code{use-percentage-for-policy?}).
15069 Possible values are:
15079 @code{'hybrid-sleep}.
15085 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
15086 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
15087 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
15088 notifications and ways to mount/unmount disks. Programs that talk to UDisks
15089 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
15092 @deffn {Scheme Procedure} colord-service [#:colord @var{colord}]
15093 Return a service that runs @command{colord}, a system service with a D-Bus
15094 interface to manage the color profiles of input and output devices such as
15095 screens and scanners. It is notably used by the GNOME Color Manager graphical
15096 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
15097 site} for more information.
15100 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
15101 Return a configuration allowing an application to access GeoClue
15102 location data. @var{name} is the Desktop ID of the application, without
15103 the @code{.desktop} part. If @var{allowed?} is true, the application
15104 will have access to location information by default. The boolean
15105 @var{system?} value indicates whether an application is a system component
15106 or not. Finally @var{users} is a list of UIDs of all users for which
15107 this application is allowed location info access. An empty users list
15108 means that all users are allowed.
15111 @defvr {Scheme Variable} %standard-geoclue-applications
15112 The standard list of well-known GeoClue application configurations,
15113 granting authority to the GNOME date-and-time utility to ask for the
15114 current location in order to set the time zone, and allowing the
15115 IceCat and Epiphany web browsers to request location information.
15116 IceCat and Epiphany both query the user before allowing a web page to
15117 know the user's location.
15120 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
15121 [#:whitelist '()] @
15122 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
15123 [#:submit-data? #f]
15124 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
15125 [#:submission-nick "geoclue"] @
15126 [#:applications %standard-geoclue-applications]
15127 Return a service that runs the GeoClue location service. This service
15128 provides a D-Bus interface to allow applications to request access to a
15129 user's physical location, and optionally to add information to online
15130 location databases. See
15131 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
15132 web site} for more information.
15135 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
15136 [@w{#:auto-enable? #f}]
15137 Return a service that runs the @command{bluetoothd} daemon, which
15138 manages all the Bluetooth devices and provides a number of D-Bus
15139 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
15140 powered automatically at boot, which can be useful when using a
15141 bluetooth keyboard or mouse.
15143 Users need to be in the @code{lp} group to access the D-Bus service.
15146 @node Sound Services
15147 @subsection Sound Services
15149 @cindex sound support
15151 @cindex PulseAudio, sound support
15153 The @code{(gnu services sound)} module provides a service to configure the
15154 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
15155 preferred ALSA output driver.
15157 @deffn {Scheme Variable} alsa-service-type
15158 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
15159 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
15160 configuration file. The value for this type is a @command{alsa-configuration}
15161 record as in this example:
15164 (service alsa-service-type)
15167 See below for details about @code{alsa-configuration}.
15170 @deftp {Data Type} alsa-configuration
15171 Data type representing the configuration for @code{alsa-service}.
15174 @item @code{alsa-plugins} (default: @var{alsa-plugins})
15175 @code{alsa-plugins} package to use.
15177 @item @code{pulseaudio?} (default: @var{#t})
15178 Whether ALSA applications should transparently be made to use the
15179 @uref{http://www.pulseaudio.org/, PulseAudio} sound server.
15181 Using PulseAudio allows you to run several sound-producing applications
15182 at the same time and to individual control them @i{via}
15183 @command{pavucontrol}, among other things.
15185 @item @code{extra-options} (default: @var{""})
15186 String to append to the @file{/etc/asound.conf} file.
15191 Individual users who want to override the system configuration of ALSA can do
15192 it with the @file{~/.asoundrc} file:
15195 # In guix, we have to specify the absolute path for plugins.
15197 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
15200 # Routing ALSA to jack:
15201 # <http://jackaudio.org/faq/routing_alsa.html>.
15205 0 system:playback_1
15206 1 system:playback_2
15223 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
15227 @node Database Services
15228 @subsection Database Services
15232 The @code{(gnu services databases)} module provides the following services.
15234 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
15235 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
15236 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
15237 Return a service that runs @var{postgresql}, the PostgreSQL database
15240 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
15241 creates a database cluster with @var{locale} as the default
15242 locale, stored in @var{data-directory}. It then listens on @var{port}.
15244 @cindex postgresql extension-packages
15245 Additional extensions are loaded from packages listed in
15246 @var{extension-packages}. Extensions are available at runtime. For instance,
15247 to create a geographic database using the @code{postgis} extension, a user can
15248 configure the postgresql-service as in this example:
15252 (use-package-modules databases geo)
15256 ;; postgresql is required to run `psql' but postgis is not required for
15257 ;; proper operation.
15258 (packages (cons* postgresql %base-packages))
15261 (postgresql-service #:extension-packages (list postgis))
15265 Then the extension becomes visible and you can initialise an empty geographic
15266 database in this way:
15270 > create database postgistest;
15271 > \connect postgistest;
15272 > create extension postgis;
15273 > create extension postgis_topology;
15276 There is no need to add this field for contrib extensions such as hstore or
15277 dblink as they are already loadable by postgresql. This field is only
15278 required to add extensions provided by other packages.
15281 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
15282 Return a service that runs @command{mysqld}, the MySQL or MariaDB
15285 The optional @var{config} argument specifies the configuration for
15286 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
15289 @deftp {Data Type} mysql-configuration
15290 Data type representing the configuration of @var{mysql-service}.
15293 @item @code{mysql} (default: @var{mariadb})
15294 Package object of the MySQL database server, can be either @var{mariadb}
15297 For MySQL, a temporary root password will be displayed at activation time.
15298 For MariaDB, the root password is empty.
15300 @item @code{port} (default: @code{3306})
15301 TCP port on which the database server listens for incoming connections.
15305 @defvr {Scheme Variable} memcached-service-type
15306 This is the service type for the @uref{https://memcached.org/,
15307 Memcached} service, which provides a distributed in memory cache. The
15308 value for the service type is a @code{memcached-configuration} object.
15312 (service memcached-service-type)
15315 @deftp {Data Type} memcached-configuration
15316 Data type representing the configuration of memcached.
15319 @item @code{memcached} (default: @code{memcached})
15320 The Memcached package to use.
15322 @item @code{interfaces} (default: @code{'("0.0.0.0")})
15323 Network interfaces on which to listen.
15325 @item @code{tcp-port} (default: @code{11211})
15326 Port on which to accept connections on,
15328 @item @code{udp-port} (default: @code{11211})
15329 Port on which to accept UDP connections on, a value of 0 will disable
15330 listening on a UDP socket.
15332 @item @code{additional-options} (default: @code{'()})
15333 Additional command line options to pass to @code{memcached}.
15337 @defvr {Scheme Variable} mongodb-service-type
15338 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
15339 The value for the service type is a @code{mongodb-configuration} object.
15343 (service mongodb-service-type)
15346 @deftp {Data Type} mongodb-configuration
15347 Data type representing the configuration of mongodb.
15350 @item @code{mongodb} (default: @code{mongodb})
15351 The MongoDB package to use.
15353 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
15354 The configuration file for MongoDB.
15356 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
15357 This value is used to create the directory, so that it exists and is
15358 owned by the mongodb user. It should match the data-directory which
15359 MongoDB is configured to use through the configuration file.
15363 @defvr {Scheme Variable} redis-service-type
15364 This is the service type for the @uref{https://redis.io/, Redis}
15365 key/value store, whose value is a @code{redis-configuration} object.
15368 @deftp {Data Type} redis-configuration
15369 Data type representing the configuration of redis.
15372 @item @code{redis} (default: @code{redis})
15373 The Redis package to use.
15375 @item @code{bind} (default: @code{"127.0.0.1"})
15376 Network interface on which to listen.
15378 @item @code{port} (default: @code{6379})
15379 Port on which to accept connections on, a value of 0 will disable
15380 listening on a TCP socket.
15382 @item @code{working-directory} (default: @code{"/var/lib/redis"})
15383 Directory in which to store the database and related files.
15387 @node Mail Services
15388 @subsection Mail Services
15392 The @code{(gnu services mail)} module provides Guix service definitions
15393 for email services: IMAP, POP3, and LMTP servers, as well as mail
15394 transport agents (MTAs). Lots of acronyms! These services are detailed
15395 in the subsections below.
15397 @subsubheading Dovecot Service
15399 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
15400 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
15403 By default, Dovecot does not need much configuration; the default
15404 configuration object created by @code{(dovecot-configuration)} will
15405 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
15406 certificate will be generated for TLS-protected connections, though
15407 Dovecot will also listen on cleartext ports by default. There are a
15408 number of options, though, which mail administrators might need to change,
15409 and as is the case with other services, Guix allows the system
15410 administrator to specify these parameters via a uniform Scheme interface.
15412 For example, to specify that mail is located at @code{maildir~/.mail},
15413 one would instantiate the Dovecot service like this:
15416 (dovecot-service #:config
15417 (dovecot-configuration
15418 (mail-location "maildir:~/.mail")))
15421 The available configuration parameters follow. Each parameter
15422 definition is preceded by its type; for example, @samp{string-list foo}
15423 indicates that the @code{foo} parameter should be specified as a list of
15424 strings. There is also a way to specify the configuration as a string,
15425 if you have an old @code{dovecot.conf} file that you want to port over
15426 from some other system; see the end for more details.
15428 @c The following documentation was initially generated by
15429 @c (generate-documentation) in (gnu services mail). Manually maintained
15430 @c documentation is better, so we shouldn't hesitate to edit below as
15431 @c needed. However if the change you want to make to this documentation
15432 @c can be done in an automated way, it's probably easier to change
15433 @c (generate-documentation) than to make it below and have to deal with
15434 @c the churn as dovecot updates.
15436 Available @code{dovecot-configuration} fields are:
15438 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
15439 The dovecot package.
15442 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
15443 A list of IPs or hosts where to listen for connections. @samp{*}
15444 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
15445 interfaces. If you want to specify non-default ports or anything more
15446 complex, customize the address and port fields of the
15447 @samp{inet-listener} of the specific services you are interested in.
15450 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
15451 List of protocols we want to serve. Available protocols include
15452 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
15454 Available @code{protocol-configuration} fields are:
15456 @deftypevr {@code{protocol-configuration} parameter} string name
15457 The name of the protocol.
15460 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
15461 UNIX socket path to the master authentication server to find users.
15462 This is used by imap (for shared users) and lda.
15463 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
15466 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
15467 Space separated list of plugins to load.
15470 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
15471 Maximum number of IMAP connections allowed for a user from each IP
15472 address. NOTE: The username is compared case-sensitively.
15473 Defaults to @samp{10}.
15478 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
15479 List of services to enable. Available services include @samp{imap},
15480 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
15483 Available @code{service-configuration} fields are:
15485 @deftypevr {@code{service-configuration} parameter} string kind
15486 The service kind. Valid values include @code{director},
15487 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
15488 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
15489 @code{tcpwrap}, @code{quota-warning}, or anything else.
15492 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
15493 Listeners for the service. A listener is either a
15494 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
15495 an @code{inet-listener-configuration}.
15496 Defaults to @samp{()}.
15498 Available @code{unix-listener-configuration} fields are:
15500 @deftypevr {@code{unix-listener-configuration} parameter} string path
15501 Path to the file, relative to @code{base-dir} field. This is also used as
15505 @deftypevr {@code{unix-listener-configuration} parameter} string mode
15506 The access mode for the socket.
15507 Defaults to @samp{"0600"}.
15510 @deftypevr {@code{unix-listener-configuration} parameter} string user
15511 The user to own the socket.
15512 Defaults to @samp{""}.
15515 @deftypevr {@code{unix-listener-configuration} parameter} string group
15516 The group to own the socket.
15517 Defaults to @samp{""}.
15521 Available @code{fifo-listener-configuration} fields are:
15523 @deftypevr {@code{fifo-listener-configuration} parameter} string path
15524 Path to the file, relative to @code{base-dir} field. This is also used as
15528 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
15529 The access mode for the socket.
15530 Defaults to @samp{"0600"}.
15533 @deftypevr {@code{fifo-listener-configuration} parameter} string user
15534 The user to own the socket.
15535 Defaults to @samp{""}.
15538 @deftypevr {@code{fifo-listener-configuration} parameter} string group
15539 The group to own the socket.
15540 Defaults to @samp{""}.
15544 Available @code{inet-listener-configuration} fields are:
15546 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
15547 The protocol to listen for.
15550 @deftypevr {@code{inet-listener-configuration} parameter} string address
15551 The address on which to listen, or empty for all addresses.
15552 Defaults to @samp{""}.
15555 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
15556 The port on which to listen.
15559 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
15560 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
15562 Defaults to @samp{#t}.
15567 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
15568 Maximum number of simultaneous client connections per process. Once
15569 this number of connections is received, the next incoming connection
15570 will prompt Dovecot to spawn another process. If set to 0,
15571 @code{default-client-limit} is used instead.
15573 Defaults to @samp{0}.
15577 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
15578 Number of connections to handle before starting a new process.
15579 Typically the only useful values are 0 (unlimited) or 1. 1 is more
15580 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
15581 Defaults to @samp{1}.
15585 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
15586 Maximum number of processes that can exist for this service. If set to
15587 0, @code{default-process-limit} is used instead.
15589 Defaults to @samp{0}.
15593 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
15594 Number of processes to always keep waiting for more connections.
15595 Defaults to @samp{0}.
15598 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
15599 If you set @samp{service-count 0}, you probably need to grow
15601 Defaults to @samp{256000000}.
15606 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
15607 Dict configuration, as created by the @code{dict-configuration}
15610 Available @code{dict-configuration} fields are:
15612 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
15613 A list of key-value pairs that this dict should hold.
15614 Defaults to @samp{()}.
15619 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
15620 A list of passdb configurations, each one created by the
15621 @code{passdb-configuration} constructor.
15623 Available @code{passdb-configuration} fields are:
15625 @deftypevr {@code{passdb-configuration} parameter} string driver
15626 The driver that the passdb should use. Valid values include
15627 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
15629 Defaults to @samp{"pam"}.
15632 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
15633 Space separated list of arguments to the passdb driver.
15634 Defaults to @samp{""}.
15639 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
15640 List of userdb configurations, each one created by the
15641 @code{userdb-configuration} constructor.
15643 Available @code{userdb-configuration} fields are:
15645 @deftypevr {@code{userdb-configuration} parameter} string driver
15646 The driver that the userdb should use. Valid values include
15647 @samp{passwd} and @samp{static}.
15648 Defaults to @samp{"passwd"}.
15651 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
15652 Space separated list of arguments to the userdb driver.
15653 Defaults to @samp{""}.
15656 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
15657 Override fields from passwd.
15658 Defaults to @samp{()}.
15663 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
15664 Plug-in configuration, created by the @code{plugin-configuration}
15668 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
15669 List of namespaces. Each item in the list is created by the
15670 @code{namespace-configuration} constructor.
15672 Available @code{namespace-configuration} fields are:
15674 @deftypevr {@code{namespace-configuration} parameter} string name
15675 Name for this namespace.
15678 @deftypevr {@code{namespace-configuration} parameter} string type
15679 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
15680 Defaults to @samp{"private"}.
15683 @deftypevr {@code{namespace-configuration} parameter} string separator
15684 Hierarchy separator to use. You should use the same separator for
15685 all namespaces or some clients get confused. @samp{/} is usually a good
15686 one. The default however depends on the underlying mail storage
15688 Defaults to @samp{""}.
15691 @deftypevr {@code{namespace-configuration} parameter} string prefix
15692 Prefix required to access this namespace. This needs to be
15693 different for all namespaces. For example @samp{Public/}.
15694 Defaults to @samp{""}.
15697 @deftypevr {@code{namespace-configuration} parameter} string location
15698 Physical location of the mailbox. This is in the same format as
15699 mail_location, which is also the default for it.
15700 Defaults to @samp{""}.
15703 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
15704 There can be only one INBOX, and this setting defines which
15706 Defaults to @samp{#f}.
15709 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
15710 If namespace is hidden, it's not advertised to clients via NAMESPACE
15711 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
15712 useful when converting from another server with different namespaces
15713 which you want to deprecate but still keep working. For example you can
15714 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
15716 Defaults to @samp{#f}.
15719 @deftypevr {@code{namespace-configuration} parameter} boolean list?
15720 Show the mailboxes under this namespace with the LIST command. This
15721 makes the namespace visible for clients that do not support the NAMESPACE
15722 extension. The special @code{children} value lists child mailboxes, but
15723 hides the namespace prefix.
15724 Defaults to @samp{#t}.
15727 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
15728 Namespace handles its own subscriptions. If set to @code{#f}, the
15729 parent namespace handles them. The empty prefix should always have this
15731 Defaults to @samp{#t}.
15734 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
15735 List of predefined mailboxes in this namespace.
15736 Defaults to @samp{()}.
15738 Available @code{mailbox-configuration} fields are:
15740 @deftypevr {@code{mailbox-configuration} parameter} string name
15741 Name for this mailbox.
15744 @deftypevr {@code{mailbox-configuration} parameter} string auto
15745 @samp{create} will automatically create this mailbox.
15746 @samp{subscribe} will both create and subscribe to the mailbox.
15747 Defaults to @samp{"no"}.
15750 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
15751 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
15752 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
15753 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
15754 Defaults to @samp{()}.
15761 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
15762 Base directory where to store runtime data.
15763 Defaults to @samp{"/var/run/dovecot/"}.
15766 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
15767 Greeting message for clients.
15768 Defaults to @samp{"Dovecot ready."}.
15771 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
15772 List of trusted network ranges. Connections from these IPs are
15773 allowed to override their IP addresses and ports (for logging and for
15774 authentication checks). @samp{disable-plaintext-auth} is also ignored
15775 for these networks. Typically you would specify your IMAP proxy servers
15777 Defaults to @samp{()}.
15780 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
15781 List of login access check sockets (e.g.@: tcpwrap).
15782 Defaults to @samp{()}.
15785 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
15786 Show more verbose process titles (in ps). Currently shows user name
15787 and IP address. Useful for seeing who is actually using the IMAP
15788 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
15790 Defaults to @samp{#f}.
15793 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
15794 Should all processes be killed when Dovecot master process shuts down.
15795 Setting this to @code{#f} means that Dovecot can be upgraded without
15796 forcing existing client connections to close (although that could also
15797 be a problem if the upgrade is e.g.@: due to a security fix).
15798 Defaults to @samp{#t}.
15801 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
15802 If non-zero, run mail commands via this many connections to doveadm
15803 server, instead of running them directly in the same process.
15804 Defaults to @samp{0}.
15807 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
15808 UNIX socket or host:port used for connecting to doveadm server.
15809 Defaults to @samp{"doveadm-server"}.
15812 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
15813 List of environment variables that are preserved on Dovecot startup
15814 and passed down to all of its child processes. You can also give
15815 key=value pairs to always set specific settings.
15818 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
15819 Disable LOGIN command and all other plaintext authentications unless
15820 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
15821 matches the local IP (i.e.@: you're connecting from the same computer),
15822 the connection is considered secure and plaintext authentication is
15823 allowed. See also ssl=required setting.
15824 Defaults to @samp{#t}.
15827 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
15828 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
15829 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
15830 for caching to be used.
15831 Defaults to @samp{0}.
15834 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
15835 Time to live for cached data. After TTL expires the cached record
15836 is no longer used, *except* if the main database lookup returns internal
15837 failure. We also try to handle password changes automatically: If
15838 user's previous authentication was successful, but this one wasn't, the
15839 cache isn't used. For now this works only with plaintext
15841 Defaults to @samp{"1 hour"}.
15844 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
15845 TTL for negative hits (user not found, password mismatch).
15846 0 disables caching them completely.
15847 Defaults to @samp{"1 hour"}.
15850 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
15851 List of realms for SASL authentication mechanisms that need them.
15852 You can leave it empty if you don't want to support multiple realms.
15853 Many clients simply use the first one listed here, so keep the default
15855 Defaults to @samp{()}.
15858 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
15859 Default realm/domain to use if none was specified. This is used for
15860 both SASL realms and appending @@domain to username in plaintext
15862 Defaults to @samp{""}.
15865 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
15866 List of allowed characters in username. If the user-given username
15867 contains a character not listed in here, the login automatically fails.
15868 This is just an extra check to make sure user can't exploit any
15869 potential quote escaping vulnerabilities with SQL/LDAP databases. If
15870 you want to allow all characters, set this value to empty.
15871 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
15874 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
15875 Username character translations before it's looked up from
15876 databases. The value contains series of from -> to characters. For
15877 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
15878 translated to @samp{@@}.
15879 Defaults to @samp{""}.
15882 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
15883 Username formatting before it's looked up from databases. You can
15884 use the standard variables here, e.g.@: %Lu would lowercase the username,
15885 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
15886 change the @samp{@@} into @samp{-AT-}. This translation is done after
15887 @samp{auth-username-translation} changes.
15888 Defaults to @samp{"%Lu"}.
15891 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
15892 If you want to allow master users to log in by specifying the master
15893 username within the normal username string (i.e.@: not using SASL
15894 mechanism's support for it), you can specify the separator character
15895 here. The format is then <username><separator><master username>.
15896 UW-IMAP uses @samp{*} as the separator, so that could be a good
15898 Defaults to @samp{""}.
15901 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
15902 Username to use for users logging in with ANONYMOUS SASL
15904 Defaults to @samp{"anonymous"}.
15907 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
15908 Maximum number of dovecot-auth worker processes. They're used to
15909 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
15910 They're automatically created and destroyed as needed.
15911 Defaults to @samp{30}.
15914 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
15915 Host name to use in GSSAPI principal names. The default is to use
15916 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
15917 allow all keytab entries.
15918 Defaults to @samp{""}.
15921 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
15922 Kerberos keytab to use for the GSSAPI mechanism. Will use the
15923 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
15924 need to change the auth service to run as root to be able to read this
15926 Defaults to @samp{""}.
15929 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
15930 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
15931 and @samp{ntlm-auth} helper.
15932 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
15933 Defaults to @samp{#f}.
15936 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
15937 Path for Samba's @samp{ntlm-auth} helper binary.
15938 Defaults to @samp{"/usr/bin/ntlm_auth"}.
15941 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
15942 Time to delay before replying to failed authentications.
15943 Defaults to @samp{"2 secs"}.
15946 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
15947 Require a valid SSL client certificate or the authentication
15949 Defaults to @samp{#f}.
15952 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
15953 Take the username from client's SSL certificate, using
15954 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
15956 Defaults to @samp{#f}.
15959 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
15960 List of wanted authentication mechanisms. Supported mechanisms are:
15961 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
15962 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
15963 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
15964 @samp{disable-plaintext-auth} setting.
15967 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
15968 List of IPs or hostnames to all director servers, including ourself.
15969 Ports can be specified as ip:port. The default port is the same as what
15970 director service's @samp{inet-listener} is using.
15971 Defaults to @samp{()}.
15974 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
15975 List of IPs or hostnames to all backend mail servers. Ranges are
15976 allowed too, like 10.0.0.10-10.0.0.30.
15977 Defaults to @samp{()}.
15980 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
15981 How long to redirect users to a specific server after it no longer
15982 has any connections.
15983 Defaults to @samp{"15 min"}.
15986 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
15987 How the username is translated before being hashed. Useful values
15988 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
15989 are shared within domain.
15990 Defaults to @samp{"%Lu"}.
15993 @deftypevr {@code{dovecot-configuration} parameter} string log-path
15994 Log file to use for error messages. @samp{syslog} logs to syslog,
15995 @samp{/dev/stderr} logs to stderr.
15996 Defaults to @samp{"syslog"}.
15999 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
16000 Log file to use for informational messages. Defaults to
16002 Defaults to @samp{""}.
16005 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
16006 Log file to use for debug messages. Defaults to
16007 @samp{info-log-path}.
16008 Defaults to @samp{""}.
16011 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
16012 Syslog facility to use if you're logging to syslog. Usually if you
16013 don't want to use @samp{mail}, you'll use local0..local7. Also other
16014 standard facilities are supported.
16015 Defaults to @samp{"mail"}.
16018 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
16019 Log unsuccessful authentication attempts and the reasons why they
16021 Defaults to @samp{#f}.
16024 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
16025 In case of password mismatches, log the attempted password. Valid
16026 values are no, plain and sha1. sha1 can be useful for detecting brute
16027 force password attempts vs. user simply trying the same password over
16028 and over again. You can also truncate the value to n chars by appending
16029 ":n" (e.g.@: sha1:6).
16030 Defaults to @samp{"no"}.
16033 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
16034 Even more verbose logging for debugging purposes. Shows for example
16036 Defaults to @samp{#f}.
16039 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
16040 In case of password mismatches, log the passwords and used scheme so
16041 the problem can be debugged. Enabling this also enables
16043 Defaults to @samp{#f}.
16046 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
16047 Enable mail process debugging. This can help you figure out why
16048 Dovecot isn't finding your mails.
16049 Defaults to @samp{#f}.
16052 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
16053 Show protocol level SSL errors.
16054 Defaults to @samp{#f}.
16057 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
16058 Prefix for each line written to log file. % codes are in
16059 strftime(3) format.
16060 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
16063 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
16064 List of elements we want to log. The elements which have a
16065 non-empty variable value are joined together to form a comma-separated
16069 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
16070 Login log format. %s contains @samp{login-log-format-elements}
16071 string, %$ contains the data we want to log.
16072 Defaults to @samp{"%$: %s"}.
16075 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
16076 Log prefix for mail processes. See doc/wiki/Variables.txt for list
16077 of possible variables you can use.
16078 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
16081 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
16082 Format to use for logging mail deliveries. You can use variables:
16085 Delivery status message (e.g.@: @samp{saved to INBOX})
16097 Defaults to @samp{"msgid=%m: %$"}.
16100 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
16101 Location for users' mailboxes. The default is empty, which means
16102 that Dovecot tries to find the mailboxes automatically. This won't work
16103 if the user doesn't yet have any mail, so you should explicitly tell
16104 Dovecot the full location.
16106 If you're using mbox, giving a path to the INBOX
16107 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
16108 where the other mailboxes are kept. This is called the "root mail
16109 directory", and it must be the first path given in the
16110 @samp{mail-location} setting.
16112 There are a few special variables you can use, eg.:
16118 user part in user@@domain, same as %u if there's no domain
16120 domain part in user@@domain, empty if there's no domain
16125 See doc/wiki/Variables.txt for full list. Some examples:
16127 @item maildir:~/Maildir
16128 @item mbox:~/mail:INBOX=/var/mail/%u
16129 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
16131 Defaults to @samp{""}.
16134 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
16135 System user and group used to access mails. If you use multiple,
16136 userdb can override these by returning uid or gid fields. You can use
16137 either numbers or names. <doc/wiki/UserIds.txt>.
16138 Defaults to @samp{""}.
16141 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
16143 Defaults to @samp{""}.
16146 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
16147 Group to enable temporarily for privileged operations. Currently
16148 this is used only with INBOX when either its initial creation or
16149 dotlocking fails. Typically this is set to "mail" to give access to
16151 Defaults to @samp{""}.
16154 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
16155 Grant access to these supplementary groups for mail processes.
16156 Typically these are used to set up access to shared mailboxes. Note
16157 that it may be dangerous to set these if users can create
16158 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
16159 could allow a user to delete others' mailboxes, or ln -s
16160 /secret/shared/box ~/mail/mybox would allow reading it).
16161 Defaults to @samp{""}.
16164 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
16165 Allow full file system access to clients. There's no access checks
16166 other than what the operating system does for the active UID/GID. It
16167 works with both maildir and mboxes, allowing you to prefix mailboxes
16168 names with e.g.@: /path/ or ~user/.
16169 Defaults to @samp{#f}.
16172 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
16173 Don't use mmap() at all. This is required if you store indexes to
16174 shared file systems (NFS or clustered file system).
16175 Defaults to @samp{#f}.
16178 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
16179 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
16180 supports @samp{O_EXCL} since version 3, so this should be safe to use
16181 nowadays by default.
16182 Defaults to @samp{#t}.
16185 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
16186 When to use fsync() or fdatasync() calls:
16189 Whenever necessary to avoid losing important data
16191 Useful with e.g.@: NFS when write()s are delayed
16193 Never use it (best performance, but crashes can lose data).
16195 Defaults to @samp{"optimized"}.
16198 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
16199 Mail storage exists in NFS. Set this to yes to make Dovecot flush
16200 NFS caches whenever needed. If you're using only a single mail server
16202 Defaults to @samp{#f}.
16205 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
16206 Mail index files also exist in NFS. Setting this to yes requires
16207 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
16208 Defaults to @samp{#f}.
16211 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
16212 Locking method for index files. Alternatives are fcntl, flock and
16213 dotlock. Dotlocking uses some tricks which may create more disk I/O
16214 than other locking methods. NFS users: flock doesn't work, remember to
16215 change @samp{mmap-disable}.
16216 Defaults to @samp{"fcntl"}.
16219 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
16220 Directory in which LDA/LMTP temporarily stores incoming mails >128
16222 Defaults to @samp{"/tmp"}.
16225 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
16226 Valid UID range for users. This is mostly to make sure that users can't
16227 log in as daemons or other system users. Note that denying root logins is
16228 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
16230 Defaults to @samp{500}.
16233 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
16235 Defaults to @samp{0}.
16238 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
16239 Valid GID range for users. Users having non-valid GID as primary group ID
16240 aren't allowed to log in. If user belongs to supplementary groups with
16241 non-valid GIDs, those groups are not set.
16242 Defaults to @samp{1}.
16245 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
16247 Defaults to @samp{0}.
16250 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
16251 Maximum allowed length for mail keyword name. It's only forced when
16252 trying to create new keywords.
16253 Defaults to @samp{50}.
16256 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
16257 List of directories under which chrooting is allowed for mail
16258 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
16259 too). This setting doesn't affect @samp{login-chroot}
16260 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
16261 "/./" in home dirs are ignored. WARNING: Never add directories here
16262 which local users can modify, that may lead to root exploit. Usually
16263 this should be done only if you don't allow shell access for users.
16264 <doc/wiki/Chrooting.txt>.
16265 Defaults to @samp{()}.
16268 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
16269 Default chroot directory for mail processes. This can be overridden
16270 for specific users in user database by giving /./ in user's home
16271 directory (e.g.@: /home/./user chroots into /home). Note that usually
16272 there is no real need to do chrooting, Dovecot doesn't allow users to
16273 access files outside their mail directory anyway. If your home
16274 directories are prefixed with the chroot directory, append "/."@: to
16275 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
16276 Defaults to @samp{""}.
16279 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
16280 UNIX socket path to master authentication server to find users.
16281 This is used by imap (for shared users) and lda.
16282 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16285 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
16286 Directory where to look up mail plugins.
16287 Defaults to @samp{"/usr/lib/dovecot"}.
16290 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
16291 List of plugins to load for all services. Plugins specific to IMAP,
16292 LDA, etc.@: are added to this list in their own .conf files.
16293 Defaults to @samp{()}.
16296 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
16297 The minimum number of mails in a mailbox before updates are done to
16298 cache file. This allows optimizing Dovecot's behavior to do less disk
16299 writes at the cost of more disk reads.
16300 Defaults to @samp{0}.
16303 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
16304 When IDLE command is running, mailbox is checked once in a while to
16305 see if there are any new mails or other changes. This setting defines
16306 the minimum time to wait between those checks. Dovecot can also use
16307 dnotify, inotify and kqueue to find out immediately when changes
16309 Defaults to @samp{"30 secs"}.
16312 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
16313 Save mails with CR+LF instead of plain LF. This makes sending those
16314 mails take less CPU, especially with sendfile() syscall with Linux and
16315 FreeBSD. But it also creates a bit more disk I/O which may just make it
16316 slower. Also note that if other software reads the mboxes/maildirs,
16317 they may handle the extra CRs wrong and cause problems.
16318 Defaults to @samp{#f}.
16321 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
16322 By default LIST command returns all entries in maildir beginning
16323 with a dot. Enabling this option makes Dovecot return only entries
16324 which are directories. This is done by stat()ing each entry, so it
16325 causes more disk I/O.
16326 (For systems setting struct @samp{dirent->d_type} this check is free
16327 and it's done always regardless of this setting).
16328 Defaults to @samp{#f}.
16331 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
16332 When copying a message, do it with hard links whenever possible.
16333 This makes the performance much better, and it's unlikely to have any
16335 Defaults to @samp{#t}.
16338 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
16339 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
16340 directory only when its mtime changes unexpectedly or when we can't find
16341 the mail otherwise.
16342 Defaults to @samp{#f}.
16345 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
16346 Which locking methods to use for locking mbox. There are four
16351 Create <mailbox>.lock file. This is the oldest and most NFS-safe
16352 solution. If you want to use /var/mail/ like directory, the users will
16353 need write access to that directory.
16355 Same as dotlock, but if it fails because of permissions or because there
16356 isn't enough disk space, just skip it.
16358 Use this if possible. Works with NFS too if lockd is used.
16360 May not exist in all systems. Doesn't work with NFS.
16362 May not exist in all systems. Doesn't work with NFS.
16365 You can use multiple locking methods; if you do the order they're declared
16366 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
16367 locking methods as well. Some operating systems don't allow using some of
16368 them simultaneously.
16371 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
16375 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
16376 Maximum time to wait for lock (all of them) before aborting.
16377 Defaults to @samp{"5 mins"}.
16380 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
16381 If dotlock exists but the mailbox isn't modified in any way,
16382 override the lock file after this much time.
16383 Defaults to @samp{"2 mins"}.
16386 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
16387 When mbox changes unexpectedly we have to fully read it to find out
16388 what changed. If the mbox is large this can take a long time. Since
16389 the change is usually just a newly appended mail, it'd be faster to
16390 simply read the new mails. If this setting is enabled, Dovecot does
16391 this but still safely fallbacks to re-reading the whole mbox file
16392 whenever something in mbox isn't how it's expected to be. The only real
16393 downside to this setting is that if some other MUA changes message
16394 flags, Dovecot doesn't notice it immediately. Note that a full sync is
16395 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
16396 Defaults to @samp{#t}.
16399 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
16400 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
16401 EXAMINE, EXPUNGE or CHECK commands. If this is set,
16402 @samp{mbox-dirty-syncs} is ignored.
16403 Defaults to @samp{#f}.
16406 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
16407 Delay writing mbox headers until doing a full write sync (EXPUNGE
16408 and CHECK commands and when closing the mailbox). This is especially
16409 useful for POP3 where clients often delete all mails. The downside is
16410 that our changes aren't immediately visible to other MUAs.
16411 Defaults to @samp{#t}.
16414 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
16415 If mbox size is smaller than this (e.g.@: 100k), don't write index
16416 files. If an index file already exists it's still read, just not
16418 Defaults to @samp{0}.
16421 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
16422 Maximum dbox file size until it's rotated.
16423 Defaults to @samp{10000000}.
16426 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
16427 Maximum dbox file age until it's rotated. Typically in days. Day
16428 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
16430 Defaults to @samp{"1d"}.
16433 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
16434 When creating new mdbox files, immediately preallocate their size to
16435 @samp{mdbox-rotate-size}. This setting currently works only in Linux
16436 with some file systems (ext4, xfs).
16437 Defaults to @samp{#f}.
16440 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
16441 sdbox and mdbox support saving mail attachments to external files,
16442 which also allows single instance storage for them. Other backends
16443 don't support this for now.
16445 WARNING: This feature hasn't been tested much yet. Use at your own risk.
16447 Directory root where to store mail attachments. Disabled, if empty.
16448 Defaults to @samp{""}.
16451 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
16452 Attachments smaller than this aren't saved externally. It's also
16453 possible to write a plugin to disable saving specific attachments
16455 Defaults to @samp{128000}.
16458 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
16459 File system backend to use for saving attachments:
16462 No SiS done by Dovecot (but this might help FS's own deduplication)
16464 SiS with immediate byte-by-byte comparison during saving
16465 @item sis-queue posix
16466 SiS with delayed comparison and deduplication.
16468 Defaults to @samp{"sis posix"}.
16471 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
16472 Hash format to use in attachment filenames. You can add any text and
16473 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
16474 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
16475 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
16476 Defaults to @samp{"%@{sha1@}"}.
16479 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
16481 Defaults to @samp{100}.
16484 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
16486 Defaults to @samp{1000}.
16489 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
16490 Default VSZ (virtual memory size) limit for service processes.
16491 This is mainly intended to catch and kill processes that leak memory
16492 before they eat up everything.
16493 Defaults to @samp{256000000}.
16496 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
16497 Login user is internally used by login processes. This is the most
16498 untrusted user in Dovecot system. It shouldn't have access to anything
16500 Defaults to @samp{"dovenull"}.
16503 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
16504 Internal user is used by unprivileged processes. It should be
16505 separate from login user, so that login processes can't disturb other
16507 Defaults to @samp{"dovecot"}.
16510 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
16511 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
16512 Defaults to @samp{"required"}.
16515 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
16516 PEM encoded X.509 SSL/TLS certificate (public key).
16517 Defaults to @samp{"</etc/dovecot/default.pem"}.
16520 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
16521 PEM encoded SSL/TLS private key. The key is opened before
16522 dropping root privileges, so keep the key file unreadable by anyone but
16524 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
16527 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
16528 If key file is password protected, give the password here.
16529 Alternatively give it when starting dovecot with -p parameter. Since
16530 this file is often world-readable, you may want to place this setting
16531 instead to a different.
16532 Defaults to @samp{""}.
16535 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
16536 PEM encoded trusted certificate authority. Set this only if you
16537 intend to use @samp{ssl-verify-client-cert? #t}. The file should
16538 contain the CA certificate(s) followed by the matching
16539 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
16540 Defaults to @samp{""}.
16543 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
16544 Require that CRL check succeeds for client certificates.
16545 Defaults to @samp{#t}.
16548 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
16549 Request client to send a certificate. If you also want to require
16550 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
16551 Defaults to @samp{#f}.
16554 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
16555 Which field from certificate to use for username. commonName and
16556 x500UniqueIdentifier are the usual choices. You'll also need to set
16557 @samp{auth-ssl-username-from-cert? #t}.
16558 Defaults to @samp{"commonName"}.
16561 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
16562 Minimum SSL protocol version to accept.
16563 Defaults to @samp{"TLSv1"}.
16566 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
16567 SSL ciphers to use.
16568 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
16571 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
16572 SSL crypto device to use, for valid values run "openssl engine".
16573 Defaults to @samp{""}.
16576 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
16577 Address to use when sending rejection mails.
16578 %d expands to recipient domain.
16579 Defaults to @samp{"postmaster@@%d"}.
16582 @deftypevr {@code{dovecot-configuration} parameter} string hostname
16583 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
16584 and in LMTP replies. Default is the system's real hostname@@domain.
16585 Defaults to @samp{""}.
16588 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
16589 If user is over quota, return with temporary failure instead of
16591 Defaults to @samp{#f}.
16594 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
16595 Binary to use for sending mails.
16596 Defaults to @samp{"/usr/sbin/sendmail"}.
16599 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
16600 If non-empty, send mails via this SMTP host[:port] instead of
16602 Defaults to @samp{""}.
16605 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
16606 Subject: header to use for rejection mails. You can use the same
16607 variables as for @samp{rejection-reason} below.
16608 Defaults to @samp{"Rejected: %s"}.
16611 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
16612 Human readable error message for rejection mails. You can use
16625 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
16628 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
16629 Delimiter character between local-part and detail in email
16631 Defaults to @samp{"+"}.
16634 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
16635 Header where the original recipient address (SMTP's RCPT TO:
16636 address) is taken from if not available elsewhere. With dovecot-lda -a
16637 parameter overrides this. A commonly used header for this is
16639 Defaults to @samp{""}.
16642 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
16643 Should saving a mail to a nonexistent mailbox automatically create
16645 Defaults to @samp{#f}.
16648 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
16649 Should automatically created mailboxes be also automatically
16651 Defaults to @samp{#f}.
16654 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
16655 Maximum IMAP command line length. Some clients generate very long
16656 command lines with huge mailboxes, so you may need to raise this if you
16657 get "Too long argument" or "IMAP command line too large" errors
16659 Defaults to @samp{64000}.
16662 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
16663 IMAP logout format string:
16666 total number of bytes read from client
16668 total number of bytes sent to client.
16670 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
16671 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@}"}.
16674 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
16675 Override the IMAP CAPABILITY response. If the value begins with '+',
16676 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
16677 Defaults to @samp{""}.
16680 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
16681 How long to wait between "OK Still here" notifications when client
16683 Defaults to @samp{"2 mins"}.
16686 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
16687 ID field names and values to send to clients. Using * as the value
16688 makes Dovecot use the default value. The following fields have default
16689 values currently: name, version, os, os-version, support-url,
16691 Defaults to @samp{""}.
16694 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
16695 ID fields sent by client to log. * means everything.
16696 Defaults to @samp{""}.
16699 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
16700 Workarounds for various client bugs:
16703 @item delay-newmail
16704 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
16705 CHECK commands. Some clients ignore them otherwise, for example OSX
16706 Mail (<v2.1). Outlook Express breaks more badly though, without this it
16707 may show user "Message no longer in server" errors. Note that OE6
16708 still breaks even with this workaround if synchronization is set to
16711 @item tb-extra-mailbox-sep
16712 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
16713 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
16714 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
16716 @item tb-lsub-flags
16717 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
16718 This makes Thunderbird realize they aren't selectable and show them
16719 greyed out, instead of only later giving "not selectable" popup error.
16721 Defaults to @samp{()}.
16724 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
16725 Host allowed in URLAUTH URLs sent by client. "*" allows all.
16726 Defaults to @samp{""}.
16730 Whew! Lots of configuration options. The nice thing about it though is
16731 that Guix has a complete interface to Dovecot's configuration
16732 language. This allows not only a nice way to declare configurations,
16733 but also offers reflective capabilities as well: users can write code to
16734 inspect and transform configurations from within Scheme.
16736 However, it could be that you just want to get a @code{dovecot.conf} up
16737 and running. In that case, you can pass an
16738 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
16739 @code{dovecot-service}. As its name indicates, an opaque configuration
16740 does not have easy reflective capabilities.
16742 Available @code{opaque-dovecot-configuration} fields are:
16744 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
16745 The dovecot package.
16748 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
16749 The contents of the @code{dovecot.conf}, as a string.
16752 For example, if your @code{dovecot.conf} is just the empty string, you
16753 could instantiate a dovecot service like this:
16756 (dovecot-service #:config
16757 (opaque-dovecot-configuration
16761 @subsubheading OpenSMTPD Service
16763 @deffn {Scheme Variable} opensmtpd-service-type
16764 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
16765 service, whose value should be an @code{opensmtpd-configuration} object
16766 as in this example:
16769 (service opensmtpd-service-type
16770 (opensmtpd-configuration
16771 (config-file (local-file "./my-smtpd.conf"))))
16775 @deftp {Data Type} opensmtpd-configuration
16776 Data type representing the configuration of opensmtpd.
16779 @item @code{package} (default: @var{opensmtpd})
16780 Package object of the OpenSMTPD SMTP server.
16782 @item @code{config-file} (default: @code{%default-opensmtpd-file})
16783 File-like object of the OpenSMTPD configuration file to use. By default
16784 it listens on the loopback network interface, and allows for mail from
16785 users and daemons on the local machine, as well as permitting email to
16786 remote servers. Run @command{man smtpd.conf} for more information.
16791 @subsubheading Exim Service
16793 @cindex mail transfer agent (MTA)
16794 @cindex MTA (mail transfer agent)
16797 @deffn {Scheme Variable} exim-service-type
16798 This is the type of the @uref{https://exim.org, Exim} mail transfer
16799 agent (MTA), whose value should be an @code{exim-configuration} object
16800 as in this example:
16803 (service exim-service-type
16804 (exim-configuration
16805 (config-file (local-file "./my-exim.conf"))))
16809 In order to use an @code{exim-service-type} service you must also have a
16810 @code{mail-aliases-service-type} service present in your
16811 @code{operating-system} (even if it has no aliases).
16813 @deftp {Data Type} exim-configuration
16814 Data type representing the configuration of exim.
16817 @item @code{package} (default: @var{exim})
16818 Package object of the Exim server.
16820 @item @code{config-file} (default: @code{#f})
16821 File-like object of the Exim configuration file to use. If its value is
16822 @code{#f} then use the default configuration file from the package
16823 provided in @code{package}. The resulting configuration file is loaded
16824 after setting the @code{exim_user} and @code{exim_group} configuration
16830 @subsubheading Getmail service
16835 @deffn {Scheme Variable} getmail-service-type
16836 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
16837 mail retriever, whose value should be an @code{getmail-configuration}.
16840 Available @code{getmail-configuration} fields are:
16842 @deftypevr {@code{getmail-configuration} parameter} symbol name
16843 A symbol to identify the getmail service.
16845 Defaults to @samp{"unset"}.
16849 @deftypevr {@code{getmail-configuration} parameter} package package
16850 The getmail package to use.
16854 @deftypevr {@code{getmail-configuration} parameter} string user
16855 The user to run getmail as.
16857 Defaults to @samp{"getmail"}.
16861 @deftypevr {@code{getmail-configuration} parameter} string group
16862 The group to run getmail as.
16864 Defaults to @samp{"getmail"}.
16868 @deftypevr {@code{getmail-configuration} parameter} string directory
16869 The getmail directory to use.
16871 Defaults to @samp{"/var/lib/getmail/default"}.
16875 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
16876 The getmail configuration file to use.
16878 Available @code{getmail-configuration-file} fields are:
16880 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
16881 What mail account to retrieve mail from, and how to access that account.
16883 Available @code{getmail-retriever-configuration} fields are:
16885 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
16886 The type of mail retriever to use. Valid values include @samp{passwd}
16889 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
16893 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
16894 Space separated list of arguments to the userdb driver.
16896 Defaults to @samp{unset}.
16900 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
16901 Space separated list of arguments to the userdb driver.
16903 Defaults to @samp{unset}.
16907 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
16908 Space separated list of arguments to the userdb driver.
16910 Defaults to @samp{#f}.
16914 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
16915 Override fields from passwd.
16917 Defaults to @samp{""}.
16921 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
16922 Override fields from passwd.
16924 Defaults to @samp{()}.
16928 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
16929 PEM-formatted key file to use for the TLS negotiation
16931 Defaults to @samp{""}.
16935 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
16936 PEM-formatted certificate file to use for the TLS negotiation
16938 Defaults to @samp{""}.
16942 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
16943 CA certificates to use
16945 Defaults to @samp{""}.
16949 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
16950 Extra retriever parameters
16952 Defaults to @samp{()}.
16958 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
16959 What to do with retrieved messages.
16961 Available @code{getmail-destination-configuration} fields are:
16963 @deftypevr {@code{getmail-destination-configuration} parameter} string type
16964 The type of mail destination. Valid values include @samp{Maildir},
16965 @samp{Mboxrd} and @samp{MDA_external}.
16967 Defaults to @samp{unset}.
16971 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
16972 The path option for the mail destination. The behaviour depends on the
16975 Defaults to @samp{""}.
16979 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
16980 Extra destination parameters
16982 Defaults to @samp{()}.
16988 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
16991 Available @code{getmail-options-configuration} fields are:
16993 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
16994 If set to @samp{0}, getmail will only print warnings and errors. A
16995 value of @samp{1} means that messages will be printed about retrieving
16996 and deleting messages. If set to @samp{2}, getmail will print messages
16997 about each of it's actions.
16999 Defaults to @samp{1}.
17003 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
17004 If true, getmail will retrieve all available messages. Otherwise it
17005 will only retrieve messages it hasn't seen previously.
17007 Defaults to @samp{#t}.
17011 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
17012 If set to true, messages will be deleted from the server after
17013 retrieving and successfully delivering them. Otherwise, messages will
17014 be left on the server.
17016 Defaults to @samp{#f}.
17020 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
17021 Getmail will delete messages this number of days after seeing them, if
17022 they have not been delivered. This means messages will be left on the
17023 server this number of days after delivering them. A value of @samp{0}
17024 disabled this feature.
17026 Defaults to @samp{0}.
17030 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
17031 Delete messages larger than this of bytes after retrieving them, even if
17032 the delete and delete-after options are disabled. A value of @samp{0}
17033 disables this feature.
17035 Defaults to @samp{0}.
17039 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
17040 Retrieve messages totalling up to this number of bytes before closing
17041 the session with the server. A value of @samp{0} disables this feature.
17043 Defaults to @samp{0}.
17047 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
17048 Don't retrieve messages larger than this number of bytes. A value of
17049 @samp{0} disables this feature.
17051 Defaults to @samp{0}.
17055 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
17056 If true, getmail will add a Delivered-To header to messages.
17058 Defaults to @samp{#t}.
17062 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
17063 If set, getmail adds a Received header to the messages.
17065 Defaults to @samp{#t}.
17069 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
17070 Getmail will record a log of its actions to the named file. A value of
17071 @samp{""} disables this feature.
17073 Defaults to @samp{""}.
17077 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
17078 If true, getmail will record a log of its actions using the system
17081 Defaults to @samp{#t}.
17085 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
17086 If true, getmail will log information about messages not retrieved and
17087 the reason for not retrieving them, as well as starting and ending
17090 Defaults to @samp{#t}.
17094 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
17095 Extra options to include.
17097 Defaults to @samp{()}.
17105 @deftypevr {@code{getmail-configuration} parameter} list idle
17106 A list of mailboxes that getmail should wait on the server for new mail
17107 notifications. This depends on the server supporting the IDLE
17110 Defaults to @samp{()}.
17114 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
17115 Environment variables to set for getmail.
17117 Defaults to @samp{()}.
17121 @subsubheading Mail Aliases Service
17123 @cindex email aliases
17124 @cindex aliases, for email addresses
17126 @deffn {Scheme Variable} mail-aliases-service-type
17127 This is the type of the service which provides @code{/etc/aliases},
17128 specifying how to deliver mail to users on this system.
17131 (service mail-aliases-service-type
17132 '(("postmaster" "bob")
17133 ("bob" "bob@@example.com" "bob@@example2.com")))
17137 The configuration for a @code{mail-aliases-service-type} service is an
17138 association list denoting how to deliver mail that comes to this
17139 system. Each entry is of the form @code{(alias addresses ...)}, with
17140 @code{alias} specifying the local alias and @code{addresses} specifying
17141 where to deliver this user's mail.
17143 The aliases aren't required to exist as users on the local system. In
17144 the above example, there doesn't need to be a @code{postmaster} entry in
17145 the @code{operating-system}'s @code{user-accounts} in order to deliver
17146 the @code{postmaster} mail to @code{bob} (which subsequently would
17147 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
17149 @subsubheading GNU Mailutils IMAP4 Daemon
17150 @cindex GNU Mailutils IMAP4 Daemon
17152 @deffn {Scheme Variable} imap4d-service-type
17153 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
17154 mailutils, GNU Mailutils Manual}), whose value should be an
17155 @code{imap4d-configuration} object as in this example:
17158 (service imap4d-service-type
17159 (imap4d-configuration
17160 (config-file (local-file "imap4d.conf"))))
17164 @deftp {Data Type} imap4d-configuration
17165 Data type representing the configuration of @command{imap4d}.
17168 @item @code{package} (default: @code{mailutils})
17169 The package that provides @command{imap4d}.
17171 @item @code{config-file} (default: @code{%default-imap4d-config-file})
17172 File-like object of the configuration file to use, by default it will listen
17173 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
17174 Mailutils Manual}, for details.
17179 @node Messaging Services
17180 @subsection Messaging Services
17185 The @code{(gnu services messaging)} module provides Guix service
17186 definitions for messaging services: currently only Prosody is supported.
17188 @subsubheading Prosody Service
17190 @deffn {Scheme Variable} prosody-service-type
17191 This is the type for the @uref{https://prosody.im, Prosody XMPP
17192 communication server}. Its value must be a @code{prosody-configuration}
17193 record as in this example:
17196 (service prosody-service-type
17197 (prosody-configuration
17198 (modules-enabled (cons "groups" "mam" %default-modules-enabled))
17201 (int-component-configuration
17202 (hostname "conference.example.net")
17204 (mod-muc (mod-muc-configuration)))))
17207 (virtualhost-configuration
17208 (domain "example.net"))))))
17211 See below for details about @code{prosody-configuration}.
17215 By default, Prosody does not need much configuration. Only one
17216 @code{virtualhosts} field is needed: it specifies the domain you wish
17219 You can perform various sanity checks on the generated configuration
17220 with the @code{prosodyctl check} command.
17222 Prosodyctl will also help you to import certificates from the
17223 @code{letsencrypt} directory so that the @code{prosody} user can access
17224 them. See @url{https://prosody.im/doc/letsencrypt}.
17227 prosodyctl --root cert import /etc/letsencrypt/live
17230 The available configuration parameters follow. Each parameter
17231 definition is preceded by its type; for example, @samp{string-list foo}
17232 indicates that the @code{foo} parameter should be specified as a list of
17233 strings. Types starting with @code{maybe-} denote parameters that won't
17234 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
17236 There is also a way to specify the configuration as a string, if you
17237 have an old @code{prosody.cfg.lua} file that you want to port over from
17238 some other system; see the end for more details.
17240 The @code{file-object} type designates either a file-like object
17241 (@pxref{G-Expressions, file-like objects}) or a file name.
17243 @c The following documentation was initially generated by
17244 @c (generate-documentation) in (gnu services messaging). Manually maintained
17245 @c documentation is better, so we shouldn't hesitate to edit below as
17246 @c needed. However if the change you want to make to this documentation
17247 @c can be done in an automated way, it's probably easier to change
17248 @c (generate-documentation) than to make it below and have to deal with
17249 @c the churn as Prosody updates.
17251 Available @code{prosody-configuration} fields are:
17253 @deftypevr {@code{prosody-configuration} parameter} package prosody
17254 The Prosody package.
17257 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
17258 Location of the Prosody data storage directory. See
17259 @url{https://prosody.im/doc/configure}.
17260 Defaults to @samp{"/var/lib/prosody"}.
17263 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
17264 Additional plugin directories. They are searched in all the specified
17265 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
17266 Defaults to @samp{()}.
17269 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
17270 Every virtual host and component needs a certificate so that clients and
17271 servers can securely verify its identity. Prosody will automatically load
17272 certificates/keys from the directory specified here.
17273 Defaults to @samp{"/etc/prosody/certs"}.
17276 @deftypevr {@code{prosody-configuration} parameter} string-list admins
17277 This is a list of accounts that are admins for the server. Note that you
17278 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
17279 @url{https://prosody.im/doc/creating_accounts}.
17280 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
17281 Defaults to @samp{()}.
17284 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
17285 Enable use of libevent for better performance under high load. See
17286 @url{https://prosody.im/doc/libevent}.
17287 Defaults to @samp{#f}.
17290 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
17291 This is the list of modules Prosody will load on startup. It looks for
17292 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
17293 Documentation on modules can be found at:
17294 @url{https://prosody.im/doc/modules}.
17295 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
17298 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
17299 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
17300 should you want to disable them then add them to this list.
17301 Defaults to @samp{()}.
17304 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
17305 Path to a text file where the shared groups are defined. If this path is
17306 empty then @samp{mod_groups} does nothing. See
17307 @url{https://prosody.im/doc/modules/mod_groups}.
17308 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
17311 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
17312 Disable account creation by default, for security. See
17313 @url{https://prosody.im/doc/creating_accounts}.
17314 Defaults to @samp{#f}.
17317 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
17318 These are the SSL/TLS-related settings. Most of them are disabled so to
17319 use Prosody's defaults. If you do not completely understand these options, do
17320 not add them to your config, it is easy to lower the security of your server
17321 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
17323 Available @code{ssl-configuration} fields are:
17325 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
17326 This determines what handshake to use.
17329 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
17330 Path to your private key file.
17333 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
17334 Path to your certificate file.
17337 @deftypevr {@code{ssl-configuration} parameter} file-object capath
17338 Path to directory containing root certificates that you wish Prosody to
17339 trust when verifying the certificates of remote servers.
17340 Defaults to @samp{"/etc/ssl/certs"}.
17343 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
17344 Path to a file containing root certificates that you wish Prosody to trust.
17345 Similar to @code{capath} but with all certificates concatenated together.
17348 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
17349 A list of verification options (these mostly map to OpenSSL's
17350 @code{set_verify()} flags).
17353 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
17354 A list of general options relating to SSL/TLS. These map to OpenSSL's
17355 @code{set_options()}. For a full list of options available in LuaSec, see the
17359 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
17360 How long a chain of certificate authorities to check when looking for a
17361 trusted root certificate.
17364 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
17365 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
17366 clients, and in what order.
17369 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
17370 A path to a file containing parameters for Diffie-Hellman key exchange. You
17371 can create such a file with:
17372 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
17375 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
17376 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
17377 @samp{"secp384r1"}.
17380 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
17381 A list of "extra" verification options.
17384 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
17385 Password for encrypted private keys.
17390 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
17391 Whether to force all client-to-server connections to be encrypted or not.
17392 See @url{https://prosody.im/doc/modules/mod_tls}.
17393 Defaults to @samp{#f}.
17396 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
17397 Set of mechanisms that will never be offered. See
17398 @url{https://prosody.im/doc/modules/mod_saslauth}.
17399 Defaults to @samp{("DIGEST-MD5")}.
17402 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
17403 Whether to force all server-to-server connections to be encrypted or not.
17404 See @url{https://prosody.im/doc/modules/mod_tls}.
17405 Defaults to @samp{#f}.
17408 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
17409 Whether to require encryption and certificate authentication. This
17410 provides ideal security, but requires servers you communicate with to support
17411 encryption AND present valid, trusted certificates. See
17412 @url{https://prosody.im/doc/s2s#security}.
17413 Defaults to @samp{#f}.
17416 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
17417 Many servers don't support encryption or have invalid or self-signed
17418 certificates. You can list domains here that will not be required to
17419 authenticate using certificates. They will be authenticated using DNS. See
17420 @url{https://prosody.im/doc/s2s#security}.
17421 Defaults to @samp{()}.
17424 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
17425 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
17426 valid certificates for some domains by specifying a list here. See
17427 @url{https://prosody.im/doc/s2s#security}.
17428 Defaults to @samp{()}.
17431 @deftypevr {@code{prosody-configuration} parameter} string authentication
17432 Select the authentication backend to use. The default provider stores
17433 passwords in plaintext and uses Prosody's configured data storage to store the
17434 authentication data. If you do not trust your server please see
17435 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
17436 about using the hashed backend. See also
17437 @url{https://prosody.im/doc/authentication}
17438 Defaults to @samp{"internal_plain"}.
17441 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
17442 Set logging options. Advanced logging configuration is not yet supported
17443 by the Prosody service. See @url{https://prosody.im/doc/logging}.
17444 Defaults to @samp{"*syslog"}.
17447 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
17448 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
17449 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
17452 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
17453 Maximum allowed size of the HTTP body (in bytes).
17456 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
17457 Some modules expose their own URL in various ways. This URL is built
17458 from the protocol, host and port used. If Prosody sits behind a proxy, the
17459 public URL will be @code{http-external-url} instead. See
17460 @url{https://prosody.im/doc/http#external_url}.
17463 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
17464 A host in Prosody is a domain on which user accounts can be created. For
17465 example if you want your users to have addresses like
17466 @samp{"john.smith@@example.com"} then you need to add a host
17467 @samp{"example.com"}. All options in this list will apply only to this host.
17469 Note: the name "virtual" host is used in configuration to avoid confusion with
17470 the actual physical host that Prosody is installed on. A single Prosody
17471 instance can serve many domains, each one defined as a VirtualHost entry in
17472 Prosody's configuration. Conversely a server that hosts a single domain would
17473 have just one VirtualHost entry.
17475 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
17477 Available @code{virtualhost-configuration} fields are:
17479 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:
17480 @deftypevr {@code{virtualhost-configuration} parameter} string domain
17481 Domain you wish Prosody to serve.
17486 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
17487 Components are extra services on a server which are available to clients,
17488 usually on a subdomain of the main server (such as
17489 @samp{"mycomponent.example.com"}). Example components might be chatroom
17490 servers, user directories, or gateways to other protocols.
17492 Internal components are implemented with Prosody-specific plugins. To add an
17493 internal component, you simply fill the hostname field, and the plugin you wish
17494 to use for the component.
17496 See @url{https://prosody.im/doc/components}.
17497 Defaults to @samp{()}.
17499 Available @code{int-component-configuration} fields are:
17501 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:
17502 @deftypevr {@code{int-component-configuration} parameter} string hostname
17503 Hostname of the component.
17506 @deftypevr {@code{int-component-configuration} parameter} string plugin
17507 Plugin you wish to use for the component.
17510 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
17511 Multi-user chat (MUC) is Prosody's module for allowing you to create
17512 hosted chatrooms/conferences for XMPP users.
17514 General information on setting up and using multi-user chatrooms can be found
17515 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
17516 which you should read if you are new to XMPP chatrooms.
17518 See also @url{https://prosody.im/doc/modules/mod_muc}.
17520 Available @code{mod-muc-configuration} fields are:
17522 @deftypevr {@code{mod-muc-configuration} parameter} string name
17523 The name to return in service discovery responses.
17524 Defaults to @samp{"Prosody Chatrooms"}.
17527 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
17528 If @samp{#t}, this will only allow admins to create new chatrooms.
17529 Otherwise anyone can create a room. The value @samp{"local"} restricts room
17530 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
17531 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
17532 restricts to service administrators only.
17533 Defaults to @samp{#f}.
17536 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
17537 Maximum number of history messages that will be sent to the member that has
17538 just joined the room.
17539 Defaults to @samp{20}.
17546 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
17547 External components use XEP-0114, which most standalone components
17548 support. To add an external component, you simply fill the hostname field. See
17549 @url{https://prosody.im/doc/components}.
17550 Defaults to @samp{()}.
17552 Available @code{ext-component-configuration} fields are:
17554 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:
17555 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
17556 Password which the component will use to log in.
17559 @deftypevr {@code{ext-component-configuration} parameter} string hostname
17560 Hostname of the component.
17565 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
17566 Port(s) Prosody listens on for component connections.
17567 Defaults to @samp{(5347)}.
17570 @deftypevr {@code{prosody-configuration} parameter} string component-interface
17571 Interface Prosody listens on for component connections.
17572 Defaults to @samp{"127.0.0.1"}.
17575 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
17576 Raw content that will be added to the configuration file.
17579 It could be that you just want to get a @code{prosody.cfg.lua}
17580 up and running. In that case, you can pass an
17581 @code{opaque-prosody-configuration} record as the value of
17582 @code{prosody-service-type}. As its name indicates, an opaque configuration
17583 does not have easy reflective capabilities.
17584 Available @code{opaque-prosody-configuration} fields are:
17586 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
17587 The prosody package.
17590 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
17591 The contents of the @code{prosody.cfg.lua} to use.
17594 For example, if your @code{prosody.cfg.lua} is just the empty
17595 string, you could instantiate a prosody service like this:
17598 (service prosody-service-type
17599 (opaque-prosody-configuration
17600 (prosody.cfg.lua "")))
17603 @c end of Prosody auto-generated documentation
17605 @subsubheading BitlBee Service
17607 @cindex IRC (Internet Relay Chat)
17608 @cindex IRC gateway
17609 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
17610 interface to a variety of messaging protocols such as XMPP.
17612 @defvr {Scheme Variable} bitlbee-service-type
17613 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
17614 gateway daemon. Its value is a @code{bitlbee-configuration} (see
17617 To have BitlBee listen on port 6667 on localhost, add this line to your
17621 (service bitlbee-service-type)
17625 @deftp {Data Type} bitlbee-configuration
17626 This is the configuration for BitlBee, with the following fields:
17629 @item @code{interface} (default: @code{"127.0.0.1"})
17630 @itemx @code{port} (default: @code{6667})
17631 Listen on the network interface corresponding to the IP address
17632 specified in @var{interface}, on @var{port}.
17634 When @var{interface} is @code{127.0.0.1}, only local clients can
17635 connect; when it is @code{0.0.0.0}, connections can come from any
17636 networking interface.
17638 @item @code{package} (default: @code{bitlbee})
17639 The BitlBee package to use.
17641 @item @code{plugins} (default: @code{'()})
17642 List of plugin packages to use---e.g., @code{bitlbee-discord}.
17644 @item @code{extra-settings} (default: @code{""})
17645 Configuration snippet added as-is to the BitlBee configuration file.
17649 @subsubheading Quassel Service
17651 @cindex IRC (Internet Relay Chat)
17652 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
17653 meaning that one or more clients can attach to and detach from the
17656 @defvr {Scheme Variable} quassel-service-type
17657 This is the service type for the @url{https://quassel-irc.org/,Quassel}
17658 IRC backend daemon. Its value is a @code{quassel-configuration}
17662 @deftp {Data Type} quassel-configuration
17663 This is the configuration for Quassel, with the following fields:
17666 @item @code{quassel} (default: @code{quassel})
17667 The Quassel package to use.
17669 @item @code{interface} (default: @code{"::,0.0.0.0"})
17670 @item @code{port} (default: @code{4242})
17671 Listen on the network interface(s) corresponding to the IPv4 or IPv6
17672 interfaces specified in the comma delimited @var{interface}, on
17675 @item @code{loglevel} (default: @code{"Info"})
17676 The level of logging desired. Accepted values are Debug, Info, Warning
17681 @node Telephony Services
17682 @subsection Telephony Services
17684 @cindex Murmur (VoIP server)
17685 @cindex VoIP server
17686 This section describes how to set up and run a Murmur server. Murmur is
17687 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
17690 @deftp {Data Type} murmur-configuration
17691 The service type for the Murmur server. An example configuration can
17695 (service murmur-service-type
17696 (murmur-configuration
17698 "Welcome to this Mumble server running on Guix!")
17699 (cert-required? #t) ;disallow text password logins
17700 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
17701 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
17704 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
17705 password with the command that is printed during the activation phase.
17707 It is recommended to register a normal Mumble user account
17708 and grant it admin or moderator rights.
17709 You can use the @code{mumble} client to
17710 login as new normal user, register yourself, and log out.
17711 For the next step login with the name @code{SuperUser} use
17712 the @code{SuperUser} password that you set previously,
17713 and grant your newly registered mumble user administrator or moderator
17714 rights and create some channels.
17716 Available @code{murmur-configuration} fields are:
17719 @item @code{package} (default: @code{mumble})
17720 Package that contains @code{bin/murmurd}.
17722 @item @code{user} (default: @code{"murmur"})
17723 User who will run the Murmur server.
17725 @item @code{group} (default: @code{"murmur"})
17726 Group of the user who will run the murmur server.
17728 @item @code{port} (default: @code{64738})
17729 Port on which the server will listen.
17731 @item @code{welcome-text} (default: @code{""})
17732 Welcome text sent to clients when they connect.
17734 @item @code{server-password} (default: @code{""})
17735 Password the clients have to enter in order to connect.
17737 @item @code{max-users} (default: @code{100})
17738 Maximum of users that can be connected to the server at once.
17740 @item @code{max-user-bandwidth} (default: @code{#f})
17741 Maximum voice traffic a user can send per second.
17743 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
17744 File name of the sqlite database.
17745 The service's user will become the owner of the directory.
17747 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
17748 File name of the log file.
17749 The service's user will become the owner of the directory.
17751 @item @code{autoban-attempts} (default: @code{10})
17752 Maximum number of logins a user can make in @code{autoban-timeframe}
17753 without getting auto banned for @code{autoban-time}.
17755 @item @code{autoban-timeframe} (default: @code{120})
17756 Timeframe for autoban in seconds.
17758 @item @code{autoban-time} (default: @code{300})
17759 Amount of time in seconds for which a client gets banned
17760 when violating the autoban limits.
17762 @item @code{opus-threshold} (default: @code{100})
17763 Percentage of clients that need to support opus
17764 before switching over to opus audio codec.
17766 @item @code{channel-nesting-limit} (default: @code{10})
17767 How deep channels can be nested at maximum.
17769 @item @code{channelname-regex} (default: @code{#f})
17770 A string in form of a Qt regular expression that channel names must conform to.
17772 @item @code{username-regex} (default: @code{#f})
17773 A string in form of a Qt regular expression that user names must conform to.
17775 @item @code{text-message-length} (default: @code{5000})
17776 Maximum size in bytes that a user can send in one text chat message.
17778 @item @code{image-message-length} (default: @code{(* 128 1024)})
17779 Maximum size in bytes that a user can send in one image message.
17781 @item @code{cert-required?} (default: @code{#f})
17782 If it is set to @code{#t} clients that use weak password authentication
17783 will not be accepted. Users must have completed the certificate wizard to join.
17785 @item @code{remember-channel?} (default: @code{#f})
17786 Should murmur remember the last channel each user was in when they disconnected
17787 and put them into the remembered channel when they rejoin.
17789 @item @code{allow-html?} (default: @code{#f})
17790 Should html be allowed in text messages, user comments, and channel descriptions.
17792 @item @code{allow-ping?} (default: @code{#f})
17793 Setting to true exposes the current user count, the maximum user count, and
17794 the server's maximum bandwidth per client to unauthenticated users. In the
17795 Mumble client, this information is shown in the Connect dialog.
17797 Disabling this setting will prevent public listing of the server.
17799 @item @code{bonjour?} (default: @code{#f})
17800 Should the server advertise itself in the local network through the bonjour protocol.
17802 @item @code{send-version?} (default: @code{#f})
17803 Should the murmur server version be exposed in ping requests.
17805 @item @code{log-days} (default: @code{31})
17806 Murmur also stores logs in the database, which are accessible via RPC.
17807 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
17808 or -1 to disable logging to the database.
17810 @item @code{obfuscate-ips?} (default: @code{#t})
17811 Should logged ips be obfuscated to protect the privacy of users.
17813 @item @code{ssl-cert} (default: @code{#f})
17814 File name of the SSL/TLS certificate used for encrypted connections.
17817 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
17819 @item @code{ssl-key} (default: @code{#f})
17820 Filepath to the ssl private key used for encrypted connections.
17822 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
17825 @item @code{ssl-dh-params} (default: @code{#f})
17826 File name of a PEM-encoded file with Diffie-Hellman parameters
17827 for the SSL/TLS encryption. Alternatively you set it to
17828 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
17829 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
17831 @item @code{ssl-ciphers} (default: @code{#f})
17832 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
17835 This option is specified using
17836 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
17837 OpenSSL cipher list notation}.
17839 It is recommended that you try your cipher string using 'openssl ciphers <string>'
17840 before setting it here, to get a feel for which cipher suites you will get.
17841 After setting this option, it is recommend that you inspect your Murmur log
17842 to ensure that Murmur is using the cipher suites that you expected it to.
17844 Note: Changing this option may impact the backwards compatibility of your
17845 Murmur server, and can remove the ability for older Mumble clients to be able
17848 @item @code{public-registration} (default: @code{#f})
17849 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
17851 You can optionally register your server in the public server list that the
17852 @code{mumble} client shows on startup.
17853 You cannot register your server if you have set a @code{server-password},
17854 or set @code{allow-ping} to @code{#f}.
17856 It might take a few hours until it shows up in the public list.
17858 @item @code{file} (default: @code{#f})
17859 Optional alternative override for this configuration.
17863 @deftp {Data Type} murmur-public-registration-configuration
17864 Configuration for public registration of a murmur service.
17868 This is a display name for your server. Not to be confused with the hostname.
17870 @item @code{password}
17871 A password to identify your registration.
17872 Subsequent updates will need the same password. Don't lose your password.
17875 This should be a @code{http://} or @code{https://} link to your web
17878 @item @code{hostname} (default: @code{#f})
17879 By default your server will be listed by its IP address.
17880 If it is set your server will be linked by this host name instead.
17886 @node Monitoring Services
17887 @subsection Monitoring Services
17889 @subsubheading Tailon Service
17891 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
17892 viewing and searching log files.
17894 The following example will configure the service with default values.
17895 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
17898 (service tailon-service-type)
17901 The following example customises more of the Tailon configuration,
17902 adding @command{sed} to the list of allowed commands.
17905 (service tailon-service-type
17906 (tailon-configuration
17908 (tailon-configuration-file
17909 (allowed-commands '("tail" "grep" "awk" "sed"))))))
17913 @deftp {Data Type} tailon-configuration
17914 Data type representing the configuration of Tailon.
17915 This type has the following parameters:
17918 @item @code{config-file} (default: @code{(tailon-configuration-file)})
17919 The configuration file to use for Tailon. This can be set to a
17920 @dfn{tailon-configuration-file} record value, or any gexp
17921 (@pxref{G-Expressions}).
17923 For example, to instead use a local file, the @code{local-file} function
17927 (service tailon-service-type
17928 (tailon-configuration
17929 (config-file (local-file "./my-tailon.conf"))))
17932 @item @code{package} (default: @code{tailon})
17933 The tailon package to use.
17938 @deftp {Data Type} tailon-configuration-file
17939 Data type representing the configuration options for Tailon.
17940 This type has the following parameters:
17943 @item @code{files} (default: @code{(list "/var/log")})
17944 List of files to display. The list can include strings for a single file
17945 or directory, or a list, where the first item is the name of a
17946 subsection, and the remaining items are the files or directories in that
17949 @item @code{bind} (default: @code{"localhost:8080"})
17950 Address and port to which Tailon should bind on.
17952 @item @code{relative-root} (default: @code{#f})
17953 URL path to use for Tailon, set to @code{#f} to not use a path.
17955 @item @code{allow-transfers?} (default: @code{#t})
17956 Allow downloading the log files in the web interface.
17958 @item @code{follow-names?} (default: @code{#t})
17959 Allow tailing of not-yet existent files.
17961 @item @code{tail-lines} (default: @code{200})
17962 Number of lines to read initially from each file.
17964 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
17965 Commands to allow running. By default, @code{sed} is disabled.
17967 @item @code{debug?} (default: @code{#f})
17968 Set @code{debug?} to @code{#t} to show debug messages.
17970 @item @code{wrap-lines} (default: @code{#t})
17971 Initial line wrapping state in the web interface. Set to @code{#t} to
17972 initially wrap lines (the default), or to @code{#f} to initially not
17975 @item @code{http-auth} (default: @code{#f})
17976 HTTP authentication type to use. Set to @code{#f} to disable
17977 authentication (the default). Supported values are @code{"digest"} or
17980 @item @code{users} (default: @code{#f})
17981 If HTTP authentication is enabled (see @code{http-auth}), access will be
17982 restricted to the credentials provided here. To configure users, use a
17983 list of pairs, where the first element of the pair is the username, and
17984 the 2nd element of the pair is the password.
17987 (tailon-configuration-file
17988 (http-auth "basic")
17989 (users '(("user1" . "password1")
17990 ("user2" . "password2"))))
17997 @subsubheading Darkstat Service
17999 Darkstat is a packet sniffer that captures network traffic, calculates
18000 statistics about usage, and serves reports over HTTP.
18002 @defvar {Scheme Variable} darkstat-service-type
18003 This is the service type for the
18004 @uref{https://unix4lyfe.org/darkstat/, darkstat}
18005 service, its value must be a @code{darkstat-configuration} record as in
18009 (service darkstat-service-type
18010 (darkstat-configuration
18011 (interface "eno1")))
18015 @deftp {Data Type} darkstat-configuration
18016 Data type representing the configuration of @command{darkstat}.
18019 @item @code{package} (default: @code{darkstat})
18020 The darkstat package to use.
18022 @item @code{interface}
18023 Capture traffic on the specified network interface.
18025 @item @code{port} (default: @code{"667"})
18026 Bind the web interface to the specified port.
18028 @item @code{bind-address} (default: @code{"127.0.0.1"})
18029 Bind the web interface to the specified address.
18031 @item @code{base} (default: @code{"/"})
18032 Specify the path of the base URL. This can be useful if
18033 @command{darkstat} is accessed via a reverse proxy.
18038 @subsubheading Prometheus Node Exporter Service
18040 @cindex prometheus-node-exporter
18041 The Prometheus ``node exporter'' makes hardware and operating system statistics
18042 provided by the Linux kernel available for the Prometheus monitoring system.
18043 This service should be deployed on all physical nodes and virtual machines,
18044 where monitoring these statistics is desirable.
18046 @defvar {Scheme variable} prometheus-node-exporter-service-type
18047 This is the service type for the
18048 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
18049 service, its value must be a @code{prometheus-node-exporter-configuration}
18050 record as in this example:
18053 (service prometheus-node-exporter-service-type
18054 (prometheus-node-exporter-configuration
18055 (web-listen-address ":9100")))
18059 @deftp {Data Type} prometheus-node-exporter-configuration
18060 Data type representing the configuration of @command{node_exporter}.
18063 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
18064 The prometheus-node-exporter package to use.
18066 @item @code{web-listen-address} (default: @code{":9100"})
18067 Bind the web interface to the specified address.
18072 @subsubheading Zabbix server
18073 @cindex zabbix zabbix-server
18074 Zabbix provides monitoring metrics, among others network utilization, CPU load
18075 and disk space consumption:
18078 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
18079 @item Auto-discovery of servers and network devices and interfaces.
18080 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
18081 @item Distributed monitoring with centralized web administration.
18082 @item Native high performance agents.
18083 @item SLA, and ITIL KPI metrics on reporting.
18084 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
18085 @item Remote command execution through Zabbix proxies.
18088 @c %start of fragment
18090 Available @code{zabbix-server-configuration} fields are:
18092 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
18093 The zabbix-server package.
18097 @deftypevr {@code{zabbix-server-configuration} parameter} string user
18098 User who will run the Zabbix server.
18100 Defaults to @samp{"zabbix"}.
18104 @deftypevr {@code{zabbix-server-configuration} parameter} group group
18105 Group who will run the Zabbix server.
18107 Defaults to @samp{"zabbix"}.
18111 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
18112 Database host name.
18114 Defaults to @samp{"127.0.0.1"}.
18118 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
18121 Defaults to @samp{"zabbix"}.
18125 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
18128 Defaults to @samp{"zabbix"}.
18132 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
18133 Database password. Please, use @code{include-files} with
18134 @code{DBPassword=SECRET} inside a specified file instead.
18136 Defaults to @samp{""}.
18140 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
18143 Defaults to @samp{5432}.
18147 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
18148 Specifies where log messages are written to:
18152 @code{system} - syslog.
18155 @code{file} - file specified with @code{log-file} parameter.
18158 @code{console} - standard output.
18162 Defaults to @samp{""}.
18166 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
18167 Log file name for @code{log-type} @code{file} parameter.
18169 Defaults to @samp{"/var/log/zabbix/server.log"}.
18173 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
18176 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
18180 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
18181 The location of certificate authority (CA) files for SSL server
18182 certificate verification.
18184 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
18188 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
18189 Location of SSL client certificates.
18191 Defaults to @samp{"/etc/ssl/certs"}.
18195 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
18196 Extra options will be appended to Zabbix server configuration file.
18198 Defaults to @samp{""}.
18202 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
18203 You may include individual files or all files in a directory in the
18204 configuration file.
18206 Defaults to @samp{()}.
18210 @c %end of fragment
18212 @subsubheading Zabbix agent
18213 @cindex zabbix zabbix-agent
18215 Zabbix agent gathers information for Zabbix server.
18217 @c %start of fragment
18219 Available @code{zabbix-agent-configuration} fields are:
18221 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
18222 The zabbix-agent package.
18226 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
18227 User who will run the Zabbix agent.
18229 Defaults to @samp{"zabbix"}.
18233 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
18234 Group who will run the Zabbix agent.
18236 Defaults to @samp{"zabbix"}.
18240 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
18241 Unique, case sensitive hostname which is required for active checks and
18242 must match hostname as configured on the server.
18244 Defaults to @samp{"Zabbix server"}.
18248 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
18249 Specifies where log messages are written to:
18253 @code{system} - syslog.
18256 @code{file} - file specified with @code{log-file} parameter.
18259 @code{console} - standard output.
18263 Defaults to @samp{""}.
18267 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
18268 Log file name for @code{log-type} @code{file} parameter.
18270 Defaults to @samp{"/var/log/zabbix/agent.log"}.
18274 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
18277 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
18281 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
18282 List of IP addresses, optionally in CIDR notation, or hostnames of
18283 Zabbix servers and Zabbix proxies. Incoming connections will be
18284 accepted only from the hosts listed here.
18286 Defaults to @samp{("127.0.0.1")}.
18290 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
18291 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
18292 proxies for active checks. If port is not specified, default port is
18293 used. If this parameter is not specified, active checks are disabled.
18295 Defaults to @samp{("127.0.0.1")}.
18299 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
18300 Extra options will be appended to Zabbix server configuration file.
18302 Defaults to @samp{""}.
18306 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
18307 You may include individual files or all files in a directory in the
18308 configuration file.
18310 Defaults to @samp{()}.
18314 @c %end of fragment
18316 @subsubheading Zabbix front-end
18317 @cindex zabbix zabbix-front-end
18319 This service provides a WEB interface to Zabbix server.
18321 @c %start of fragment
18323 Available @code{zabbix-front-end-configuration} fields are:
18325 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
18326 NGINX configuration.
18330 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
18331 Database host name.
18333 Defaults to @samp{"localhost"}.
18337 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
18340 Defaults to @samp{5432}.
18344 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
18347 Defaults to @samp{"zabbix"}.
18351 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
18354 Defaults to @samp{"zabbix"}.
18358 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
18359 Database password. Please, use @code{db-secret-file} instead.
18361 Defaults to @samp{""}.
18365 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
18366 Secret file which will be appended to @file{zabbix.conf.php} file. This
18367 file contains credentials for use by Zabbix front-end. You are expected
18368 to create it manually.
18370 Defaults to @samp{""}.
18374 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
18375 Zabbix server hostname.
18377 Defaults to @samp{"localhost"}.
18381 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
18382 Zabbix server port.
18384 Defaults to @samp{10051}.
18389 @c %end of fragment
18391 @node Kerberos Services
18392 @subsection Kerberos Services
18395 The @code{(gnu services kerberos)} module provides services relating to
18396 the authentication protocol @dfn{Kerberos}.
18398 @subsubheading Krb5 Service
18400 Programs using a Kerberos client library normally
18401 expect a configuration file in @file{/etc/krb5.conf}.
18402 This service generates such a file from a definition provided in the
18403 operating system declaration.
18404 It does not cause any daemon to be started.
18406 No ``keytab'' files are provided by this service---you must explicitly create them.
18407 This service is known to work with the MIT client library, @code{mit-krb5}.
18408 Other implementations have not been tested.
18410 @defvr {Scheme Variable} krb5-service-type
18411 A service type for Kerberos 5 clients.
18415 Here is an example of its use:
18417 (service krb5-service-type
18418 (krb5-configuration
18419 (default-realm "EXAMPLE.COM")
18420 (allow-weak-crypto? #t)
18423 (name "EXAMPLE.COM")
18424 (admin-server "groucho.example.com")
18425 (kdc "karl.example.com"))
18428 (admin-server "kerb-admin.argrx.edu")
18429 (kdc "keys.argrx.edu"))))))
18433 This example provides a Kerberos@tie{}5 client configuration which:
18435 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
18436 of which have distinct administration servers and key distribution centers;
18437 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
18438 specified by clients;
18439 @item Accepts services which only support encryption types known to be weak.
18442 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
18443 Only the most commonly used ones are described here.
18444 For a full list, and more detailed explanation of each, see the MIT
18445 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
18449 @deftp {Data Type} krb5-realm
18450 @cindex realm, kerberos
18453 This field is a string identifying the name of the realm.
18454 A common convention is to use the fully qualified DNS name of your organization,
18455 converted to upper case.
18457 @item @code{admin-server}
18458 This field is a string identifying the host where the administration server is
18462 This field is a string identifying the key distribution center
18467 @deftp {Data Type} krb5-configuration
18470 @item @code{allow-weak-crypto?} (default: @code{#f})
18471 If this flag is @code{#t} then services which only offer encryption algorithms
18472 known to be weak will be accepted.
18474 @item @code{default-realm} (default: @code{#f})
18475 This field should be a string identifying the default Kerberos
18476 realm for the client.
18477 You should set this field to the name of your Kerberos realm.
18478 If this value is @code{#f}
18479 then a realm must be specified with every Kerberos principal when invoking programs
18480 such as @command{kinit}.
18482 @item @code{realms}
18483 This should be a non-empty list of @code{krb5-realm} objects, which clients may
18485 Normally, one of them will have a @code{name} field matching the @code{default-realm}
18491 @subsubheading PAM krb5 Service
18494 The @code{pam-krb5} service allows for login authentication and password
18495 management via Kerberos.
18496 You will need this service if you want PAM enabled applications to authenticate
18497 users using Kerberos.
18499 @defvr {Scheme Variable} pam-krb5-service-type
18500 A service type for the Kerberos 5 PAM module.
18503 @deftp {Data Type} pam-krb5-configuration
18504 Data type representing the configuration of the Kerberos 5 PAM module.
18505 This type has the following parameters:
18507 @item @code{pam-krb5} (default: @code{pam-krb5})
18508 The pam-krb5 package to use.
18510 @item @code{minimum-uid} (default: @code{1000})
18511 The smallest user ID for which Kerberos authentications should be attempted.
18512 Local accounts with lower values will silently fail to authenticate.
18517 @node LDAP Services
18518 @subsection LDAP Services
18520 @cindex nslcd, LDAP service
18522 The @code{(gnu services authentication)} module provides the
18523 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
18524 server. In addition to configuring the service itself, you may want to add
18525 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
18526 Switch} for detailed information.
18528 Here is a simple operating system declaration with a default configuration of
18529 the @code{nslcd-service-type} and a Name Service Switch configuration that
18530 consults the @code{ldap} name service last:
18533 (use-service-modules authentication)
18534 (use-modules (gnu system nss))
18540 (service nslcd-service-type)
18541 (service dhcp-client-service-type)
18543 (name-service-switch
18544 (let ((services (list (name-service (name "db"))
18545 (name-service (name "files"))
18546 (name-service (name "ldap")))))
18547 (name-service-switch
18548 (inherit %mdns-host-lookup-nss)
18549 (password services)
18552 (netgroup services)
18553 (gshadow services)))))
18556 @c %start of generated documentation for nslcd-configuration
18558 Available @code{nslcd-configuration} fields are:
18560 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
18561 The @code{nss-pam-ldapd} package to use.
18565 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
18566 The number of threads to start that can handle requests and perform LDAP
18567 queries. Each thread opens a separate connection to the LDAP server.
18568 The default is to start 5 threads.
18570 Defaults to @samp{disabled}.
18574 @deftypevr {@code{nslcd-configuration} parameter} string uid
18575 This specifies the user id with which the daemon should be run.
18577 Defaults to @samp{"nslcd"}.
18581 @deftypevr {@code{nslcd-configuration} parameter} string gid
18582 This specifies the group id with which the daemon should be run.
18584 Defaults to @samp{"nslcd"}.
18588 @deftypevr {@code{nslcd-configuration} parameter} log-option log
18589 This option controls the way logging is done via a list containing
18590 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
18591 or "syslog", or an absolute file name. The LEVEL argument is optional
18592 and specifies the log level. The log level may be one of the following
18593 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
18594 messages with the specified log level or higher are logged.
18596 Defaults to @samp{("/var/log/nslcd" info)}.
18600 @deftypevr {@code{nslcd-configuration} parameter} list uri
18601 The list of LDAP server URIs. Normally, only the first server will be
18602 used with the following servers as fall-back.
18604 Defaults to @samp{("ldap://localhost:389/")}.
18608 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
18609 The version of the LDAP protocol to use. The default is to use the
18610 maximum version supported by the LDAP library.
18612 Defaults to @samp{disabled}.
18616 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
18617 Specifies the distinguished name with which to bind to the directory
18618 server for lookups. The default is to bind anonymously.
18620 Defaults to @samp{disabled}.
18624 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
18625 Specifies the credentials with which to bind. This option is only
18626 applicable when used with binddn.
18628 Defaults to @samp{disabled}.
18632 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
18633 Specifies the distinguished name to use when the root user tries to
18634 modify a user's password using the PAM module.
18636 Defaults to @samp{disabled}.
18640 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
18641 Specifies the credentials with which to bind if the root user tries to
18642 change a user's password. This option is only applicable when used with
18645 Defaults to @samp{disabled}.
18649 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
18650 Specifies the SASL mechanism to be used when performing SASL
18653 Defaults to @samp{disabled}.
18657 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
18658 Specifies the SASL realm to be used when performing SASL authentication.
18660 Defaults to @samp{disabled}.
18664 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
18665 Specifies the authentication identity to be used when performing SASL
18668 Defaults to @samp{disabled}.
18672 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
18673 Specifies the authorization identity to be used when performing SASL
18676 Defaults to @samp{disabled}.
18680 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
18681 Determines whether the LDAP server host name should be canonicalised. If
18682 this is enabled the LDAP library will do a reverse host name lookup. By
18683 default, it is left up to the LDAP library whether this check is
18686 Defaults to @samp{disabled}.
18690 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
18691 Set the name for the GSS-API Kerberos credentials cache.
18693 Defaults to @samp{disabled}.
18697 @deftypevr {@code{nslcd-configuration} parameter} string base
18698 The directory search base.
18700 Defaults to @samp{"dc=example,dc=com"}.
18704 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
18705 Specifies the search scope (subtree, onelevel, base or children). The
18706 default scope is subtree; base scope is almost never useful for name
18707 service lookups; children scope is not supported on all servers.
18709 Defaults to @samp{(subtree)}.
18713 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
18714 Specifies the policy for dereferencing aliases. The default policy is
18715 to never dereference aliases.
18717 Defaults to @samp{disabled}.
18721 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
18722 Specifies whether automatic referral chasing should be enabled. The
18723 default behaviour is to chase referrals.
18725 Defaults to @samp{disabled}.
18729 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
18730 This option allows for custom attributes to be looked up instead of the
18731 default RFC 2307 attributes. It is a list of maps, each consisting of
18732 the name of a map, the RFC 2307 attribute to match and the query
18733 expression for the attribute as it is available in the directory.
18735 Defaults to @samp{()}.
18739 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
18740 A list of filters consisting of the name of a map to which the filter
18741 applies and an LDAP search filter expression.
18743 Defaults to @samp{()}.
18747 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
18748 Specifies the time limit in seconds to use when connecting to the
18749 directory server. The default value is 10 seconds.
18751 Defaults to @samp{disabled}.
18755 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
18756 Specifies the time limit (in seconds) to wait for a response from the
18757 LDAP server. A value of zero, which is the default, is to wait
18758 indefinitely for searches to be completed.
18760 Defaults to @samp{disabled}.
18764 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
18765 Specifies the period if inactivity (in seconds) after which the con‐
18766 nection to the LDAP server will be closed. The default is not to time
18769 Defaults to @samp{disabled}.
18773 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
18774 Specifies the number of seconds to sleep when connecting to all LDAP
18775 servers fails. By default one second is waited between the first
18776 failure and the first retry.
18778 Defaults to @samp{disabled}.
18782 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
18783 Specifies the time after which the LDAP server is considered to be
18784 permanently unavailable. Once this time is reached retries will be done
18785 only once per this time period. The default value is 10 seconds.
18787 Defaults to @samp{disabled}.
18791 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
18792 Specifies whether to use SSL/TLS or not (the default is not to). If
18793 'start-tls is specified then StartTLS is used rather than raw LDAP over
18796 Defaults to @samp{disabled}.
18800 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
18801 Specifies what checks to perform on a server-supplied certificate. The
18802 meaning of the values is described in the ldap.conf(5) manual page.
18804 Defaults to @samp{disabled}.
18808 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
18809 Specifies the directory containing X.509 certificates for peer authen‐
18810 tication. This parameter is ignored when using GnuTLS.
18812 Defaults to @samp{disabled}.
18816 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
18817 Specifies the path to the X.509 certificate for peer authentication.
18819 Defaults to @samp{disabled}.
18823 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
18824 Specifies the path to an entropy source. This parameter is ignored when
18827 Defaults to @samp{disabled}.
18831 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
18832 Specifies the ciphers to use for TLS as a string.
18834 Defaults to @samp{disabled}.
18838 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
18839 Specifies the path to the file containing the local certificate for
18840 client TLS authentication.
18842 Defaults to @samp{disabled}.
18846 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
18847 Specifies the path to the file containing the private key for client TLS
18850 Defaults to @samp{disabled}.
18854 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
18855 Set this to a number greater than 0 to request paged results from the
18856 LDAP server in accordance with RFC2696. The default (0) is to not
18857 request paged results.
18859 Defaults to @samp{disabled}.
18863 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
18864 This option prevents group membership lookups through LDAP for the
18865 specified users. Alternatively, the value 'all-local may be used. With
18866 that value nslcd builds a full list of non-LDAP users on startup.
18868 Defaults to @samp{disabled}.
18872 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
18873 This option ensures that LDAP users with a numeric user id lower than
18874 the specified value are ignored.
18876 Defaults to @samp{disabled}.
18880 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
18881 This option specifies an offset that is added to all LDAP numeric user
18882 ids. This can be used to avoid user id collisions with local users.
18884 Defaults to @samp{disabled}.
18888 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
18889 This option specifies an offset that is added to all LDAP numeric group
18890 ids. This can be used to avoid user id collisions with local groups.
18892 Defaults to @samp{disabled}.
18896 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
18897 If this option is set, the member attribute of a group may point to
18898 another group. Members of nested groups are also returned in the higher
18899 level group and parent groups are returned when finding groups for a
18900 specific user. The default is not to perform extra searches for nested
18903 Defaults to @samp{disabled}.
18907 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
18908 If this option is set, the group member list is not retrieved when
18909 looking up groups. Lookups for finding which groups a user belongs to
18910 will remain functional so the user will likely still get the correct
18911 groups assigned on login.
18913 Defaults to @samp{disabled}.
18917 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
18918 If this option is set, functions which cause all user/group entries to
18919 be loaded from the directory will not succeed in doing so. This can
18920 dramatically reduce LDAP server load in situations where there are a
18921 great number of users and/or groups. This option is not recommended for
18922 most configurations.
18924 Defaults to @samp{disabled}.
18928 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
18929 This option can be used to specify how user and group names are verified
18930 within the system. This pattern is used to check all user and group
18931 names that are requested and returned from LDAP.
18933 Defaults to @samp{disabled}.
18937 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
18938 This specifies whether or not to perform searches using case-insensitive
18939 matching. Enabling this could open up the system to authorization
18940 bypass vulnerabilities and introduce nscd cache poisoning
18941 vulnerabilities which allow denial of service.
18943 Defaults to @samp{disabled}.
18947 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
18948 This option specifies whether password policy controls are requested and
18949 handled from the LDAP server when performing user authentication.
18951 Defaults to @samp{disabled}.
18955 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
18956 By default nslcd performs an LDAP search with the user's credentials
18957 after BIND (authentication) to ensure that the BIND operation was
18958 successful. The default search is a simple check to see if the user's
18959 DN exists. A search filter can be specified that will be used instead.
18960 It should return at least one entry.
18962 Defaults to @samp{disabled}.
18966 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
18967 This option allows flexible fine tuning of the authorisation check that
18968 should be performed. The search filter specified is executed and if any
18969 entries match, access is granted, otherwise access is denied.
18971 Defaults to @samp{disabled}.
18975 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
18976 If this option is set password modification using pam_ldap will be
18977 denied and the specified message will be presented to the user instead.
18978 The message can be used to direct the user to an alternative means of
18979 changing their password.
18981 Defaults to @samp{disabled}.
18985 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
18986 List of pam service names for which LDAP authentication should suffice.
18988 Defaults to @samp{()}.
18992 @c %end of generated documentation for nslcd-configuration
18996 @subsection Web Services
19001 The @code{(gnu services web)} module provides the Apache HTTP Server,
19002 the nginx web server, and also a fastcgi wrapper daemon.
19004 @subsubheading Apache HTTP Server
19006 @deffn {Scheme Variable} httpd-service-type
19007 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
19008 (@dfn{httpd}). The value for this service type is a
19009 @code{httpd-configuration} record.
19011 A simple example configuration is given below.
19014 (service httpd-service-type
19015 (httpd-configuration
19018 (server-name "www.example.com")
19019 (document-root "/srv/http/www.example.com")))))
19022 Other services can also extend the @code{httpd-service-type} to add to
19026 (simple-service 'my-extra-server httpd-service-type
19030 (list (string-append
19031 "ServerName "www.example.com
19032 DocumentRoot \"/srv/http/www.example.com\"")))))
19036 The details for the @code{httpd-configuration}, @code{httpd-module},
19037 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
19040 @deffn {Data Type} httpd-configuration
19041 This data type represents the configuration for the httpd service.
19044 @item @code{package} (default: @code{httpd})
19045 The httpd package to use.
19047 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19048 The pid file used by the shepherd-service.
19050 @item @code{config} (default: @code{(httpd-config-file)})
19051 The configuration file to use with the httpd service. The default value
19052 is a @code{httpd-config-file} record, but this can also be a different
19053 G-expression that generates a file, for example a @code{plain-file}. A
19054 file outside of the store can also be specified through a string.
19059 @deffn {Data Type} httpd-module
19060 This data type represents a module for the httpd service.
19064 The name of the module.
19067 The file for the module. This can be relative to the httpd package being
19068 used, the absolute location of a file, or a G-expression for a file
19069 within the store, for example @code{(file-append mod-wsgi
19070 "/modules/mod_wsgi.so")}.
19075 @defvr {Scheme Variable} %default-httpd-modules
19076 A default list of @code{httpd-module} objects.
19079 @deffn {Data Type} httpd-config-file
19080 This data type represents a configuration file for the httpd service.
19083 @item @code{modules} (default: @code{%default-httpd-modules})
19084 The modules to load. Additional modules can be added here, or loaded by
19085 additional configuration.
19087 For example, in order to handle requests for PHP files, you can use Apache’s
19088 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
19091 (service httpd-service-type
19092 (httpd-configuration
19097 (name "proxy_module")
19098 (file "modules/mod_proxy.so"))
19100 (name "proxy_fcgi_module")
19101 (file "modules/mod_proxy_fcgi.so"))
19102 %default-httpd-modules))
19103 (extra-config (list "\
19104 <FilesMatch \\.php$>
19105 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
19106 </FilesMatch>"))))))
19107 (service php-fpm-service-type
19108 (php-fpm-configuration
19109 (socket "/var/run/php-fpm.sock")
19110 (socket-group "httpd")))
19113 @item @code{server-root} (default: @code{httpd})
19114 The @code{ServerRoot} in the configuration file, defaults to the httpd
19115 package. Directives including @code{Include} and @code{LoadModule} are
19116 taken as relative to the server root.
19118 @item @code{server-name} (default: @code{#f})
19119 The @code{ServerName} in the configuration file, used to specify the
19120 request scheme, hostname and port that the server uses to identify
19123 This doesn't need to be set in the server config, and can be specifyed
19124 in virtual hosts. The default is @code{#f} to not specify a
19127 @item @code{document-root} (default: @code{"/srv/http"})
19128 The @code{DocumentRoot} from which files will be served.
19130 @item @code{listen} (default: @code{'("80")})
19131 The list of values for the @code{Listen} directives in the config
19132 file. The value should be a list of strings, when each string can
19133 specify the port number to listen on, and optionally the IP address and
19136 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19137 The @code{PidFile} to use. This should match the @code{pid-file} set in
19138 the @code{httpd-configuration} so that the Shepherd service is
19139 configured correctly.
19141 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
19142 The @code{ErrorLog} to which the server will log errors.
19144 @item @code{user} (default: @code{"httpd"})
19145 The @code{User} which the server will answer requests as.
19147 @item @code{group} (default: @code{"httpd"})
19148 The @code{Group} which the server will answer requests as.
19150 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
19151 A flat list of strings and G-expressions which will be added to the end
19152 of the configuration file.
19154 Any values which the service is extended with will be appended to this
19160 @deffn {Data Type} httpd-virtualhost
19161 This data type represents a virtualhost configuration block for the httpd service.
19163 These should be added to the extra-config for the httpd-service.
19166 (simple-service 'my-extra-server httpd-service-type
19170 (list (string-append
19171 "ServerName "www.example.com
19172 DocumentRoot \"/srv/http/www.example.com\"")))))
19176 @item @code{addresses-and-ports}
19177 The addresses and ports for the @code{VirtualHost} directive.
19179 @item @code{contents}
19180 The contents of the @code{VirtualHost} directive, this should be a list
19181 of strings and G-expressions.
19186 @subsubheading NGINX
19188 @deffn {Scheme Variable} nginx-service-type
19189 Service type for the @uref{https://nginx.org/,NGinx} web server. The
19190 value for this service type is a @code{<nginx-configuration>} record.
19192 A simple example configuration is given below.
19195 (service nginx-service-type
19196 (nginx-configuration
19198 (list (nginx-server-configuration
19199 (server-name '("www.example.com"))
19200 (root "/srv/http/www.example.com"))))))
19203 In addition to adding server blocks to the service configuration
19204 directly, this service can be extended by other services to add server
19205 blocks, as in this example:
19208 (simple-service 'my-extra-server nginx-service-type
19209 (list (nginx-server-configuration
19210 (root "/srv/http/extra-website")
19211 (try-files (list "$uri" "$uri/index.html")))))
19215 At startup, @command{nginx} has not yet read its configuration file, so
19216 it uses a default file to log error messages. If it fails to load its
19217 configuration file, that is where error messages are logged. After the
19218 configuration file is loaded, the default error log file changes as per
19219 configuration. In our case, startup error messages can be found in
19220 @file{/var/run/nginx/logs/error.log}, and after configuration in
19221 @file{/var/log/nginx/error.log}. The second location can be changed
19222 with the @var{log-directory} configuration option.
19224 @deffn {Data Type} nginx-configuration
19225 This data type represents the configuration for NGinx. Some
19226 configuration can be done through this and the other provided record
19227 types, or alternatively, a config file can be provided.
19230 @item @code{nginx} (default: @code{nginx})
19231 The nginx package to use.
19233 @item @code{log-directory} (default: @code{"/var/log/nginx"})
19234 The directory to which NGinx will write log files.
19236 @item @code{run-directory} (default: @code{"/var/run/nginx"})
19237 The directory in which NGinx will create a pid file, and write temporary
19240 @item @code{server-blocks} (default: @code{'()})
19241 A list of @dfn{server blocks} to create in the generated configuration
19242 file, the elements should be of type
19243 @code{<nginx-server-configuration>}.
19245 The following example would setup NGinx to serve @code{www.example.com}
19246 from the @code{/srv/http/www.example.com} directory, without using
19249 (service nginx-service-type
19250 (nginx-configuration
19252 (list (nginx-server-configuration
19253 (server-name '("www.example.com"))
19254 (root "/srv/http/www.example.com"))))))
19257 @item @code{upstream-blocks} (default: @code{'()})
19258 A list of @dfn{upstream blocks} to create in the generated configuration
19259 file, the elements should be of type
19260 @code{<nginx-upstream-configuration>}.
19262 Configuring upstreams through the @code{upstream-blocks} can be useful
19263 when combined with @code{locations} in the
19264 @code{<nginx-server-configuration>} records. The following example
19265 creates a server configuration with one location configuration, that
19266 will proxy requests to a upstream configuration, which will handle
19267 requests with two servers.
19272 (nginx-configuration
19274 (list (nginx-server-configuration
19275 (server-name '("www.example.com"))
19276 (root "/srv/http/www.example.com")
19279 (nginx-location-configuration
19281 (body '("proxy_pass http://server-proxy;"))))))))
19283 (list (nginx-upstream-configuration
19284 (name "server-proxy")
19285 (servers (list "server1.example.com"
19286 "server2.example.com")))))))
19289 @item @code{file} (default: @code{#f})
19290 If a configuration @var{file} is provided, this will be used, rather than
19291 generating a configuration file from the provided @code{log-directory},
19292 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
19293 proper operation, these arguments should match what is in @var{file} to ensure
19294 that the directories are created when the service is activated.
19296 This can be useful if you have an existing configuration file, or it's
19297 not possible to do what is required through the other parts of the
19298 nginx-configuration record.
19300 @item @code{server-names-hash-bucket-size} (default: @code{#f})
19301 Bucket size for the server names hash tables, defaults to @code{#f} to
19302 use the size of the processors cache line.
19304 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
19305 Maximum bucket size for the server names hash tables.
19307 @item @code{extra-content} (default: @code{""})
19308 Extra content for the @code{http} block. Should be string or a string
19309 valued G-expression.
19314 @deftp {Data Type} nginx-server-configuration
19315 Data type representing the configuration of an nginx server block.
19316 This type has the following parameters:
19319 @item @code{listen} (default: @code{'("80" "443 ssl")})
19320 Each @code{listen} directive sets the address and port for IP, or the
19321 path for a UNIX-domain socket on which the server will accept requests.
19322 Both address and port, or only address or only port can be specified.
19323 An address may also be a hostname, for example:
19326 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
19329 @item @code{server-name} (default: @code{(list 'default)})
19330 A list of server names this server represents. @code{'default} represents the
19331 default server for connections matching no other server.
19333 @item @code{root} (default: @code{"/srv/http"})
19334 Root of the website nginx will serve.
19336 @item @code{locations} (default: @code{'()})
19337 A list of @dfn{nginx-location-configuration} or
19338 @dfn{nginx-named-location-configuration} records to use within this
19341 @item @code{index} (default: @code{(list "index.html")})
19342 Index files to look for when clients ask for a directory. If it cannot be found,
19343 Nginx will send the list of files in the directory.
19345 @item @code{try-files} (default: @code{'()})
19346 A list of files whose existence is checked in the specified order.
19347 @code{nginx} will use the first file it finds to process the request.
19349 @item @code{ssl-certificate} (default: @code{#f})
19350 Where to find the certificate for secure connections. Set it to @code{#f} if
19351 you don't have a certificate or you don't want to use HTTPS.
19353 @item @code{ssl-certificate-key} (default: @code{#f})
19354 Where to find the private key for secure connections. Set it to @code{#f} if
19355 you don't have a key or you don't want to use HTTPS.
19357 @item @code{server-tokens?} (default: @code{#f})
19358 Whether the server should add its configuration to response.
19360 @item @code{raw-content} (default: @code{'()})
19361 A list of raw lines added to the server block.
19366 @deftp {Data Type} nginx-upstream-configuration
19367 Data type representing the configuration of an nginx @code{upstream}
19368 block. This type has the following parameters:
19372 Name for this group of servers.
19374 @item @code{servers}
19375 Specify the addresses of the servers in the group. The address can be
19376 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
19377 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
19378 prefix @samp{unix:}. For addresses using an IP address or domain name,
19379 the default port is 80, and a different port can be specified
19385 @deftp {Data Type} nginx-location-configuration
19386 Data type representing the configuration of an nginx @code{location}
19387 block. This type has the following parameters:
19391 URI which this location block matches.
19393 @anchor{nginx-location-configuration body}
19395 Body of the location block, specified as a list of strings. This can contain
19397 configuration directives. For example, to pass requests to a upstream
19398 server group defined using an @code{nginx-upstream-configuration} block,
19399 the following directive would be specified in the body @samp{(list "proxy_pass
19400 http://upstream-name;")}.
19405 @deftp {Data Type} nginx-named-location-configuration
19406 Data type representing the configuration of an nginx named location
19407 block. Named location blocks are used for request redirection, and not
19408 used for regular request processing. This type has the following
19413 Name to identify this location block.
19416 @xref{nginx-location-configuration body}, as the body for named location
19417 blocks can be used in a similar way to the
19418 @code{nginx-location-configuration body}. One restriction is that the
19419 body of a named location block cannot contain location blocks.
19424 @subsubheading Varnish Cache
19426 Varnish is a fast cache server that sits in between web applications
19427 and end users. It proxies requests from clients and caches the
19428 accessed URLs such that multiple requests for the same resource only
19429 creates one request to the back-end.
19431 @defvr {Scheme Variable} varnish-service-type
19432 Service type for the Varnish daemon.
19435 @deftp {Data Type} varnish-configuration
19436 Data type representing the @code{varnish} service configuration.
19437 This type has the following parameters:
19440 @item @code{package} (default: @code{varnish})
19441 The Varnish package to use.
19443 @item @code{name} (default: @code{"default"})
19444 A name for this Varnish instance. Varnish will create a directory in
19445 @file{/var/varnish/} with this name and keep temporary files there. If
19446 the name starts with a forward slash, it is interpreted as an absolute
19449 Pass the @code{-n} argument to other Varnish programs to connect to the
19450 named instance, e.g.@: @command{varnishncsa -n default}.
19452 @item @code{backend} (default: @code{"localhost:8080"})
19453 The backend to use. This option has no effect if @code{vcl} is set.
19455 @item @code{vcl} (default: #f)
19456 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
19457 is @code{#f}, Varnish will proxy @code{backend} using the default
19458 configuration. Otherwise this must be a file-like object with valid
19461 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
19462 For example, to mirror @url{http://www.gnu.org,www.gnu.org} with VCL you
19463 can do something along these lines:
19466 (define %gnu-mirror
19470 backend gnu @{ .host = "www.gnu.org"; @}"))
19474 (services (cons (service varnish-service-type
19475 (varnish-configuration
19477 (vcl %gnu-mirror)))
19481 The configuration of an already running Varnish instance can be inspected
19482 and changed using the @command{varnishadm} program.
19484 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
19485 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
19486 comprehensive documentation on Varnish and its configuration language.
19488 @item @code{listen} (default: @code{'("localhost:80")})
19489 List of addresses Varnish will listen on.
19491 @item @code{storage} (default: @code{'("malloc,128m")})
19492 List of storage backends that will be available in VCL.
19494 @item @code{parameters} (default: @code{'()})
19495 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
19497 @item @code{extra-options} (default: @code{'()})
19498 Additional arguments to pass to the @command{varnishd} process.
19503 @subsubheading Patchwork
19505 Patchwork is a patch tracking system. It can collect patches sent to a
19506 mailing list, and display them in a web interface.
19508 @defvr {Scheme Variable} patchwork-service-type
19509 Service type for Patchwork.
19512 The following example is an example of a minimal service for Patchwork, for
19513 the @code{patchwork.example.com} domain.
19516 (service patchwork-service-type
19517 (patchwork-configuration
19518 (domain "patchwork.example.com")
19520 (patchwork-settings-module
19521 (allowed-hosts (list domain))
19522 (default-from-email "patchwork@@patchwork.example.com")))
19523 (getmail-retriever-config
19524 (getmail-retriever-configuration
19525 (type "SimpleIMAPSSLRetriever")
19526 (server "imap.example.com")
19528 (username "patchwork")
19530 (list (file-append coreutils "/bin/cat")
19531 "/etc/getmail-patchwork-imap-password"))
19533 '((mailboxes . ("Patches"))))))))
19537 There are three records for configuring the Patchwork service. The
19538 @code{<patchwork-configuration>} relates to the configuration for Patchwork
19539 within the HTTPD service.
19541 The @code{settings-module} field within the @code{<patchwork-configuration>}
19542 record can be populated with the @code{<patchwork-settings-module>} record,
19543 which describes a settings module that is generated within the Guix store.
19545 For the @code{database-configuration} field within the
19546 @code{<patchwork-settings-module>}, the
19547 @code{<patchwork-database-configuration>} must be used.
19549 @deftp {Data Type} patchwork-configuration
19550 Data type representing the Patchwork service configuration. This type has the
19551 following parameters:
19554 @item @code{patchwork} (default: @code{patchwork})
19555 The Patchwork package to use.
19557 @item @code{domain}
19558 The domain to use for Patchwork, this is used in the HTTPD service virtual
19561 @item @code{settings-module}
19562 The settings module to use for Patchwork. As a Django application, Patchwork
19563 is configured with a Python module containing the settings. This can either be
19564 an instance of the @code{<patchwork-settings-module>} record, any other record
19565 that represents the settings in the store, or a directory outside of the
19568 @item @code{static-path} (default: @code{"/static/"})
19569 The path under which the HTTPD service should serve the static files.
19571 @item @code{getmail-retriever-config}
19572 The getmail-retriever-configuration record value to use with
19573 Patchwork. Getmail will be configured with this value, the messages will be
19574 delivered to Patchwork.
19579 @deftp {Data Type} patchwork-settings-module
19580 Data type representing a settings module for Patchwork. Some of these
19581 settings relate directly to Patchwork, but others relate to Django, the web
19582 framework used by Patchwork, or the Django Rest Framework library. This type
19583 has the following parameters:
19586 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
19587 The database connection settings used for Patchwork. See the
19588 @code{<patchwork-database-configuration>} record type for more information.
19590 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
19591 Patchwork, as a Django web application uses a secret key for cryptographically
19592 signing values. This file should contain a unique unpredictable value.
19594 If this file does not exist, it will be created and populated with a random
19595 value by the patchwork-setup shepherd service.
19597 This setting relates to Django.
19599 @item @code{allowed-hosts}
19600 A list of valid hosts for this Patchwork service. This should at least include
19601 the domain specified in the @code{<patchwork-configuration>} record.
19603 This is a Django setting.
19605 @item @code{default-from-email}
19606 The email address from which Patchwork should send email by default.
19608 This is a Patchwork setting.
19610 @item @code{static-url} (default: @code{#f})
19611 The URL to use when serving static assets. It can be part of a URL, or a full
19612 URL, but must end in a @code{/}.
19614 If the default value is used, the @code{static-path} value from the
19615 @code{<patchwork-configuration>} record will be used.
19617 This is a Django setting.
19619 @item @code{admins} (default: @code{'()})
19620 Email addresses to send the details of errors that occur. Each value should
19621 be a list containing two elements, the name and then the email address.
19623 This is a Django setting.
19625 @item @code{debug?} (default: @code{#f})
19626 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
19627 messages will be shown.
19629 This is a Django setting.
19631 @item @code{enable-rest-api?} (default: @code{#t})
19632 Whether to enable the Patchwork REST API.
19634 This is a Patchwork setting.
19636 @item @code{enable-xmlrpc?} (default: @code{#t})
19637 Whether to enable the XML RPC API.
19639 This is a Patchwork setting.
19641 @item @code{force-https-links?} (default: @code{#t})
19642 Whether to use HTTPS links on Patchwork pages.
19644 This is a Patchwork setting.
19646 @item @code{extra-settings} (default: @code{""})
19647 Extra code to place at the end of the Patchwork settings module.
19652 @deftp {Data Type} patchwork-database-configuration
19653 Data type representing the database configuration for Patchwork.
19656 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
19657 The database engine to use.
19659 @item @code{name} (default: @code{"patchwork"})
19660 The name of the database to use.
19662 @item @code{user} (default: @code{"httpd"})
19663 The user to connect to the database as.
19665 @item @code{password} (default: @code{""})
19666 The password to use when connecting to the database.
19668 @item @code{host} (default: @code{""})
19669 The host to make the database connection to.
19671 @item @code{port} (default: @code{""})
19672 The port on which to connect to the database.
19677 @subsubheading FastCGI
19680 FastCGI is an interface between the front-end and the back-end of a web
19681 service. It is a somewhat legacy facility; new web services should
19682 generally just talk HTTP between the front-end and the back-end.
19683 However there are a number of back-end services such as PHP or the
19684 optimized HTTP Git repository access that use FastCGI, so we have
19685 support for it in Guix.
19687 To use FastCGI, you configure the front-end web server (e.g., nginx) to
19688 dispatch some subset of its requests to the fastcgi backend, which
19689 listens on a local TCP or UNIX socket. There is an intermediary
19690 @code{fcgiwrap} program that sits between the actual backend process and
19691 the web server. The front-end indicates which backend program to run,
19692 passing that information to the @code{fcgiwrap} process.
19694 @defvr {Scheme Variable} fcgiwrap-service-type
19695 A service type for the @code{fcgiwrap} FastCGI proxy.
19698 @deftp {Data Type} fcgiwrap-configuration
19699 Data type representing the configuration of the @code{fcgiwrap} service.
19700 This type has the following parameters:
19702 @item @code{package} (default: @code{fcgiwrap})
19703 The fcgiwrap package to use.
19705 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
19706 The socket on which the @code{fcgiwrap} process should listen, as a
19707 string. Valid @var{socket} values include
19708 @code{unix:@var{/path/to/unix/socket}},
19709 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
19710 @code{tcp6:[@var{ipv6_addr}]:port}.
19712 @item @code{user} (default: @code{fcgiwrap})
19713 @itemx @code{group} (default: @code{fcgiwrap})
19714 The user and group names, as strings, under which to run the
19715 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
19716 the user asks for the specific user or group names @code{fcgiwrap} that
19717 the corresponding user and/or group is present on the system.
19719 It is possible to configure a FastCGI-backed web service to pass HTTP
19720 authentication information from the front-end to the back-end, and to
19721 allow @code{fcgiwrap} to run the back-end process as a corresponding
19722 local user. To enable this capability on the back-end., run
19723 @code{fcgiwrap} as the @code{root} user and group. Note that this
19724 capability also has to be configured on the front-end as well.
19729 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
19730 with some additional features useful for sites of any size.
19732 These features include:
19734 @item Adaptive process spawning
19735 @item Basic statistics (similar to Apache's mod_status)
19736 @item Advanced process management with graceful stop/start
19737 @item Ability to start workers with different uid/gid/chroot/environment
19738 and different php.ini (replaces safe_mode)
19739 @item Stdout & stderr logging
19740 @item Emergency restart in case of accidental opcode cache destruction
19741 @item Accelerated upload support
19742 @item Support for a "slowlog"
19743 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
19744 a special function to finish request & flush all data while continuing to do
19745 something time-consuming (video converting, stats processing, etc.)
19747 ...@: and much more.
19749 @defvr {Scheme Variable} php-fpm-service-type
19750 A Service type for @code{php-fpm}.
19753 @deftp {Data Type} php-fpm-configuration
19754 Data Type for php-fpm service configuration.
19756 @item @code{php} (default: @code{php})
19757 The php package to use.
19758 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
19759 The address on which to accept FastCGI requests. Valid syntaxes are:
19761 @item @code{"ip.add.re.ss:port"}
19762 Listen on a TCP socket to a specific address on a specific port.
19763 @item @code{"port"}
19764 Listen on a TCP socket to all addresses on a specific port.
19765 @item @code{"/path/to/unix/socket"}
19766 Listen on a unix socket.
19769 @item @code{user} (default: @code{php-fpm})
19770 User who will own the php worker processes.
19771 @item @code{group} (default: @code{php-fpm})
19772 Group of the worker processes.
19773 @item @code{socket-user} (default: @code{php-fpm})
19774 User who can speak to the php-fpm socket.
19775 @item @code{socket-group} (default: @code{php-fpm})
19776 Group that can speak to the php-fpm socket.
19777 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
19778 The process id of the php-fpm process is written to this file
19779 once the service has started.
19780 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
19781 Log for the php-fpm master process.
19782 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
19783 Detailed settings for the php-fpm process manager.
19786 @item @code{<php-fpm-dynamic-process-manager-configuration>}
19787 @item @code{<php-fpm-static-process-manager-configuration>}
19788 @item @code{<php-fpm-on-demand-process-manager-configuration>}
19790 @item @code{display-errors} (default @code{#f})
19791 Determines whether php errors and warning should be sent to clients
19792 and displayed in their browsers.
19793 This is useful for local php development, but a security risk for public sites,
19794 as error messages can reveal passwords and personal data.
19795 @item @code{timezone} (default @code{#f})
19796 Specifies @code{php_admin_value[date.timezone]} parameter.
19797 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
19798 This file will log the @code{stderr} outputs of php worker processes.
19799 Can be set to @code{#f} to disable logging.
19800 @item @code{file} (default @code{#f})
19801 An optional override of the whole configuration.
19802 You can use the @code{mixed-text-file} function or an absolute filepath for it.
19806 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
19807 Data Type for the @code{dynamic} php-fpm process manager. With the
19808 @code{dynamic} process manager, spare worker processes are kept around
19809 based on it's configured limits.
19811 @item @code{max-children} (default: @code{5})
19812 Maximum of worker processes.
19813 @item @code{start-servers} (default: @code{2})
19814 How many worker processes should be started on start-up.
19815 @item @code{min-spare-servers} (default: @code{1})
19816 How many spare worker processes should be kept around at minimum.
19817 @item @code{max-spare-servers} (default: @code{3})
19818 How many spare worker processes should be kept around at maximum.
19822 @deftp {Data type} php-fpm-static-process-manager-configuration
19823 Data Type for the @code{static} php-fpm process manager. With the
19824 @code{static} process manager, an unchanging number of worker processes
19827 @item @code{max-children} (default: @code{5})
19828 Maximum of worker processes.
19832 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
19833 Data Type for the @code{on-demand} php-fpm process manager. With the
19834 @code{on-demand} process manager, worker processes are only created as
19837 @item @code{max-children} (default: @code{5})
19838 Maximum of worker processes.
19839 @item @code{process-idle-timeout} (default: @code{10})
19840 The time in seconds after which a process with no requests is killed.
19845 @deffn {Scheme Procedure} nginx-php-fpm-location @
19846 [#:nginx-package nginx] @
19847 [socket (string-append "/var/run/php" @
19848 (version-major (package-version php)) @
19850 A helper function to quickly add php to an @code{nginx-server-configuration}.
19853 A simple services setup for nginx with php can look like this:
19855 (services (cons* (service dhcp-client-service-type)
19856 (service php-fpm-service-type)
19857 (service nginx-service-type
19858 (nginx-server-configuration
19859 (server-name '("example.com"))
19860 (root "/srv/http/")
19862 (list (nginx-php-location)))
19864 (ssl-certificate #f)
19865 (ssl-certificate-key #f)))
19869 @cindex cat-avatar-generator
19870 The cat avatar generator is a simple service to demonstrate the use of php-fpm
19871 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
19872 the hash of a user's email address.
19874 @deffn {Scheme Procedure} cat-avatar-generator-service @
19875 [#:cache-dir "/var/cache/cat-avatar-generator"] @
19876 [#:package cat-avatar-generator] @
19877 [#:configuration (nginx-server-configuration)]
19878 Returns an nginx-server-configuration that inherits @code{configuration}. It
19879 extends the nginx configuration to add a server block that serves @code{package},
19880 a version of cat-avatar-generator. During execution, cat-avatar-generator will
19881 be able to use @code{cache-dir} as its cache directory.
19884 A simple setup for cat-avatar-generator can look like this:
19886 (services (cons* (cat-avatar-generator-service
19888 (nginx-server-configuration
19889 (server-name '("example.com"))))
19894 @subsubheading Hpcguix-web
19896 @cindex hpcguix-web
19897 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
19898 program is a customizable web interface to browse Guix packages,
19899 initially designed for users of high-performance computing (HPC)
19902 @defvr {Scheme Variable} hpcguix-web-service-type
19903 The service type for @code{hpcguix-web}.
19906 @deftp {Data Type} hpcguix-web-configuration
19907 Data type for the hpcguix-web service configuration.
19911 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
19912 configuration. The main items available in this spec are:
19915 @item @code{title-prefix} (default: @code{"hpcguix | "})
19916 The page title prefix.
19918 @item @code{guix-command} (default: @code{"guix"})
19919 The @command{guix} command.
19921 @item @code{package-filter-proc} (default: @code{(const #t)})
19922 A procedure specifying how to filter packages that are displayed.
19924 @item @code{package-page-extension-proc} (default: @code{(const '())})
19925 Extension package for @code{hpcguix-web}.
19927 @item @code{menu} (default: @code{'()})
19928 Additional entry in page @code{menu}.
19930 @item @code{channels} (default: @code{%default-channels})
19931 List of channels from which the package list is built (@pxref{Channels}).
19933 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
19934 The expiration time, in seconds, after which the package list is rebuilt from
19935 the latest instances of the given channels.
19938 See the hpcguix-web repository for a
19939 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
19942 @item @code{package} (default: @code{hpcguix-web})
19943 The hpcguix-web package to use.
19947 A typical hpcguix-web service declaration looks like this:
19950 (service hpcguix-web-service-type
19951 (hpcguix-web-configuration
19953 #~(define site-config
19954 (hpcweb-configuration
19955 (title-prefix "Guix-HPC - ")
19956 (menu '(("/about" "ABOUT"))))))))
19960 The hpcguix-web service periodically updates the package list it publishes by
19961 pulling channels from Git. To that end, it needs to access X.509 certificates
19962 so that it can authenticate Git servers when communicating over HTTPS, and it
19963 assumes that @file{/etc/ssl/certs} contains those certificates.
19965 Thus, make sure to add @code{nss-certs} or another certificate package to the
19966 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
19967 more information on X.509 certificates.
19970 @node Certificate Services
19971 @subsection Certificate Services
19974 @cindex HTTP, HTTPS
19975 @cindex Let's Encrypt
19976 @cindex TLS certificates
19977 The @code{(gnu services certbot)} module provides a service to
19978 automatically obtain a valid TLS certificate from the Let's Encrypt
19979 certificate authority. These certificates can then be used to serve
19980 content securely over HTTPS or other TLS-based protocols, with the
19981 knowledge that the client will be able to verify the server's
19984 @url{https://letsencrypt.org/, Let's Encrypt} provides the
19985 @code{certbot} tool to automate the certification process. This tool
19986 first securely generates a key on the server. It then makes a request
19987 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
19988 checks that the request originates from the host in question by using a
19989 challenge-response protocol, requiring the server to provide its
19990 response over HTTP. If that protocol completes successfully, the CA
19991 signs the key, resulting in a certificate. That certificate is valid
19992 for a limited period of time, and therefore to continue to provide TLS
19993 services, the server needs to periodically ask the CA to renew its
19996 The certbot service automates this process: the initial key
19997 generation, the initial certification request to the Let's Encrypt
19998 service, the web server challenge/response integration, writing the
19999 certificate to disk, the automated periodic renewals, and the deployment
20000 tasks associated with the renewal (e.g.@: reloading services, copying keys
20001 with different permissions).
20003 Certbot is run twice a day, at a random minute within the hour. It
20004 won't do anything until your certificates are due for renewal or
20005 revoked, but running it regularly would give your service a chance of
20006 staying online in case a Let's Encrypt-initiated revocation happened for
20009 By using this service, you agree to the ACME Subscriber Agreement, which
20010 can be found there:
20011 @url{https://acme-v01.api.letsencrypt.org/directory}.
20013 @defvr {Scheme Variable} certbot-service-type
20014 A service type for the @code{certbot} Let's Encrypt client. Its value
20015 must be a @code{certbot-configuration} record as in this example:
20018 (define %nginx-deploy-hook
20020 "nginx-deploy-hook"
20021 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
20022 (kill pid SIGHUP))))
20024 (service certbot-service-type
20025 (certbot-configuration
20026 (email "foo@@example.net")
20029 (certificate-configuration
20030 (domains '("example.net" "www.example.net"))
20031 (deploy-hook %nginx-deploy-hook))
20032 (certificate-configuration
20033 (domains '("bar.example.net")))))))
20036 See below for details about @code{certbot-configuration}.
20039 @deftp {Data Type} certbot-configuration
20040 Data type representing the configuration of the @code{certbot} service.
20041 This type has the following parameters:
20044 @item @code{package} (default: @code{certbot})
20045 The certbot package to use.
20047 @item @code{webroot} (default: @code{/var/www})
20048 The directory from which to serve the Let's Encrypt challenge/response
20051 @item @code{certificates} (default: @code{()})
20052 A list of @code{certificates-configuration}s for which to generate
20053 certificates and request signatures. Each certificate has a @code{name}
20054 and several @code{domains}.
20057 Mandatory email used for registration, recovery contact, and important
20058 account notifications.
20060 @item @code{rsa-key-size} (default: @code{2048})
20061 Size of the RSA key.
20063 @item @code{default-location} (default: @i{see below})
20064 The default @code{nginx-location-configuration}. Because @code{certbot}
20065 needs to be able to serve challenges and responses, it needs to be able
20066 to run a web server. It does so by extending the @code{nginx} web
20067 service with an @code{nginx-server-configuration} listening on the
20068 @var{domains} on port 80, and which has a
20069 @code{nginx-location-configuration} for the @code{/.well-known/} URI
20070 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
20071 these nginx configuration data types.
20073 Requests to other URL paths will be matched by the
20074 @code{default-location}, which if present is added to all
20075 @code{nginx-server-configuration}s.
20077 By default, the @code{default-location} will issue a redirect from
20078 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
20079 you to define what to serve on your site via @code{https}.
20081 Pass @code{#f} to not issue a default location.
20085 @deftp {Data Type} certificate-configuration
20086 Data type representing the configuration of a certificate.
20087 This type has the following parameters:
20090 @item @code{name} (default: @i{see below})
20091 This name is used by Certbot for housekeeping and in file paths; it
20092 doesn't affect the content of the certificate itself. To see
20093 certificate names, run @code{certbot certificates}.
20095 Its default is the first provided domain.
20097 @item @code{domains} (default: @code{()})
20098 The first domain provided will be the subject CN of the certificate, and
20099 all domains will be Subject Alternative Names on the certificate.
20101 @item @code{challenge} (default: @code{#f})
20102 The challenge type that has to be run by certbot. If @code{#f} is specified,
20103 default to the HTTP challenge. If a value is specified, defaults to the
20104 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
20105 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}).
20107 @item @code{authentication-hook} (default: @code{#f})
20108 Command to be run in a shell once for each certificate challenge to be
20109 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
20110 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
20111 contains the validation string and @code{$CERTBOT_TOKEN} contains the
20112 file name of the resource requested when performing an HTTP-01 challenge.
20114 @item @code{cleanup-hook} (default: @code{#f})
20115 Command to be run in a shell once for each certificate challenge that
20116 have been answered by the @code{auth-hook}. For this command, the shell
20117 variables available in the @code{auth-hook} script are still available, and
20118 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
20119 of the @code{auth-hook} script.
20121 @item @code{deploy-hook} (default: @code{#f})
20122 Command to be run in a shell once for each successfully issued
20123 certificate. For this command, the shell variable
20124 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
20125 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
20126 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
20127 contain a space-delimited list of renewed certificate domains (for
20128 example, @samp{"example.com www.example.com"}.
20133 For each @code{certificate-configuration}, the certificate is saved to
20134 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
20135 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
20137 @subsection DNS Services
20138 @cindex DNS (domain name system)
20139 @cindex domain name system (DNS)
20141 The @code{(gnu services dns)} module provides services related to the
20142 @dfn{domain name system} (DNS). It provides a server service for hosting
20143 an @emph{authoritative} DNS server for multiple zones, slave or master.
20144 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
20145 caching and forwarding DNS server for the LAN, which uses
20146 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
20148 @subsubheading Knot Service
20150 An example configuration of an authoritative server for two zones, one master
20154 (define-zone-entries example.org.zone
20155 ;; Name TTL Class Type Data
20156 ("@@" "" "IN" "A" "127.0.0.1")
20157 ("@@" "" "IN" "NS" "ns")
20158 ("ns" "" "IN" "A" "127.0.0.1"))
20160 (define master-zone
20161 (knot-zone-configuration
20162 (domain "example.org")
20164 (origin "example.org")
20165 (entries example.org.zone)))))
20168 (knot-zone-configuration
20169 (domain "plop.org")
20170 (dnssec-policy "default")
20171 (master (list "plop-master"))))
20173 (define plop-master
20174 (knot-remote-configuration
20176 (address (list "208.76.58.171"))))
20180 (services (cons* (service knot-service-type
20181 (knot-configuration
20182 (remotes (list plop-master))
20183 (zones (list master-zone slave-zone))))
20188 @deffn {Scheme Variable} knot-service-type
20189 This is the type for the Knot DNS server.
20191 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
20192 zones, that is to say domain names you would buy from a registrar. This server
20193 is not a resolver, meaning that it can only resolve names for which it is
20194 authoritative. This server can be configured to serve zones as a master server
20195 or a slave server as a per-zone basis. Slave zones will get their data from
20196 masters, and will serve it as an authoritative server. From the point of view
20197 of a resolver, there is no difference between master and slave.
20199 The following data types are used to configure the Knot DNS server:
20202 @deftp {Data Type} knot-key-configuration
20203 Data type representing a key.
20204 This type has the following parameters:
20207 @item @code{id} (default: @code{""})
20208 An identifier for other configuration fields to refer to this key. IDs must
20209 be unique and must not be empty.
20211 @item @code{algorithm} (default: @code{#f})
20212 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
20213 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
20214 and @code{'hmac-sha512}.
20216 @item @code{secret} (default: @code{""})
20217 The secret key itself.
20222 @deftp {Data Type} knot-acl-configuration
20223 Data type representing an Access Control List (ACL) configuration.
20224 This type has the following parameters:
20227 @item @code{id} (default: @code{""})
20228 An identifier for ether configuration fields to refer to this key. IDs must be
20229 unique and must not be empty.
20231 @item @code{address} (default: @code{'()})
20232 An ordered list of IP addresses, network subnets, or network ranges represented
20233 with strings. The query must match one of them. Empty value means that
20234 address match is not required.
20236 @item @code{key} (default: @code{'()})
20237 An ordered list of references to keys represented with strings. The string
20238 must match a key ID defined in a @code{knot-key-configuration}. No key means
20239 that a key is not require to match that ACL.
20241 @item @code{action} (default: @code{'()})
20242 An ordered list of actions that are permitted or forbidden by this ACL. Possible
20243 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
20244 and @code{'update}.
20246 @item @code{deny?} (default: @code{#f})
20247 When true, the ACL defines restrictions. Listed actions are forbidden. When
20248 false, listed actions are allowed.
20253 @deftp {Data Type} zone-entry
20254 Data type represnting a record entry in a zone file.
20255 This type has the following parameters:
20258 @item @code{name} (default: @code{"@@"})
20259 The name of the record. @code{"@@"} refers to the origin of the zone. Names
20260 are relative to the origin of the zone. For example, in the @code{example.org}
20261 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
20262 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
20263 refers to @code{ns.example.org}.
20265 @item @code{ttl} (default: @code{""})
20266 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
20268 @item @code{class} (default: @code{"IN"})
20269 The class of the record. Knot currently supports only @code{"IN"} and
20270 partially @code{"CH"}.
20272 @item @code{type} (default: @code{"A"})
20273 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
20274 address), NS (Name Server) and MX (Mail eXchange). Many other types are
20277 @item @code{data} (default: @code{""})
20278 The data contained in the record. For instance an IP address associated with
20279 an A record, or a domain name associated with an NS record. Remember that
20280 domain names are relative to the origin unless they end with a dot.
20285 @deftp {Data Type} zone-file
20286 Data type representing the content of a zone file.
20287 This type has the following parameters:
20290 @item @code{entries} (default: @code{'()})
20291 The list of entries. The SOA record is taken care of, so you don't need to
20292 put it in the list of entries. This list should probably contain an entry
20293 for your primary authoritative DNS server. Other than using a list of entries
20294 directly, you can use @code{define-zone-entries} to define a object containing
20295 the list of entries more easily, that you can later pass to the @code{entries}
20296 field of the @code{zone-file}.
20298 @item @code{origin} (default: @code{""})
20299 The name of your zone. This parameter cannot be empty.
20301 @item @code{ns} (default: @code{"ns"})
20302 The domain of your primary authoritative DNS server. The name is relative to
20303 the origin, unless it ends with a dot. It is mandatory that this primary
20304 DNS server corresponds to an NS record in the zone and that it is associated
20305 to an IP address in the list of entries.
20307 @item @code{mail} (default: @code{"hostmaster"})
20308 An email address people can contact you at, as the owner of the zone. This
20309 is translated as @code{<mail>@@<origin>}.
20311 @item @code{serial} (default: @code{1})
20312 The serial number of the zone. As this is used to keep track of changes by
20313 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
20314 Always increment it when you make a change in your zone.
20316 @item @code{refresh} (default: @code{(* 2 24 3600)})
20317 The frequency at which slaves will do a zone transfer. This value is a number
20318 of seconds. It can be computed by multiplications or with
20319 @code{(string->duration)}.
20321 @item @code{retry} (default: @code{(* 15 60)})
20322 The period after which a slave will retry to contact its master when it fails
20323 to do so a first time.
20325 @item @code{expiry} (default: @code{(* 14 24 3600)})
20326 Default TTL of records. Existing records are considered correct for at most
20327 this amount of time. After this period, resolvers will invalidate their cache
20328 and check again that it still exists.
20330 @item @code{nx} (default: @code{3600})
20331 Default TTL of inexistant records. This delay is usually short because you want
20332 your new domains to reach everyone quickly.
20337 @deftp {Data Type} knot-remote-configuration
20338 Data type representing a remote configuration.
20339 This type has the following parameters:
20342 @item @code{id} (default: @code{""})
20343 An identifier for other configuration fields to refer to this remote. IDs must
20344 be unique and must not be empty.
20346 @item @code{address} (default: @code{'()})
20347 An ordered list of destination IP addresses. Addresses are tried in sequence.
20348 An optional port can be given with the @@ separator. For instance:
20349 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
20351 @item @code{via} (default: @code{'()})
20352 An ordered list of source IP addresses. An empty list will have Knot choose
20353 an appropriate source IP. An optional port can be given with the @@ separator.
20354 The default is to choose at random.
20356 @item @code{key} (default: @code{#f})
20357 A reference to a key, that is a string containing the identifier of a key
20358 defined in a @code{knot-key-configuration} field.
20363 @deftp {Data Type} knot-keystore-configuration
20364 Data type representing a keystore to hold dnssec keys.
20365 This type has the following parameters:
20368 @item @code{id} (default: @code{""})
20369 The id of the keystore. It must not be empty.
20371 @item @code{backend} (default: @code{'pem})
20372 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
20374 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
20375 The configuration string of the backend. An example for the PKCS#11 is:
20376 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
20377 For the pem backend, the string reprensents a path in the file system.
20382 @deftp {Data Type} knot-policy-configuration
20383 Data type representing a dnssec policy. Knot DNS is able to automatically
20384 sign your zones. It can either generate and manage your keys automatically or
20385 use keys that you generate.
20387 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
20388 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
20389 zone. In order to be trusted, the KSK needs to be present in the parent zone
20390 (usually a top-level domain). If your registrar supports dnssec, you will
20391 have to send them your KSK's hash so they can add a DS record in their zone.
20392 This is not automated and need to be done each time you change your KSK.
20394 The policy also defines the lifetime of keys. Usually, ZSK can be changed
20395 easily and use weaker cryptographic functions (they use lower parameters) in
20396 order to sign records quickly, so they are changed often. The KSK however
20397 requires manual interaction with the registrar, so they are changed less often
20398 and use stronger parameters because they sign only one record.
20400 This type has the following parameters:
20403 @item @code{id} (default: @code{""})
20404 The id of the policy. It must not be empty.
20406 @item @code{keystore} (default: @code{"default"})
20407 A reference to a keystore, that is a string containing the identifier of a
20408 keystore defined in a @code{knot-keystore-configuration} field. The
20409 @code{"default"} identifier means the default keystore (a kasp database that
20410 was setup by this service).
20412 @item @code{manual?} (default: @code{#f})
20413 Whether the key management is manual or automatic.
20415 @item @code{single-type-signing?} (default: @code{#f})
20416 When @code{#t}, use the Single-Type Signing Scheme.
20418 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
20419 An algorithm of signing keys and issued signatures.
20421 @item @code{ksk-size} (default: @code{256})
20422 The length of the KSK. Note that this value is correct for the default
20423 algorithm, but would be unsecure for other algorithms.
20425 @item @code{zsk-size} (default: @code{256})
20426 The length of the ZSK. Note that this value is correct for the default
20427 algorithm, but would be unsecure for other algorithms.
20429 @item @code{dnskey-ttl} (default: @code{'default})
20430 The TTL value for DNSKEY records added into zone apex. The special
20431 @code{'default} value means same as the zone SOA TTL.
20433 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
20434 The period between ZSK publication and the next rollover initiation.
20436 @item @code{propagation-delay} (default: @code{(* 24 3600)})
20437 An extra delay added for each key rollover step. This value should be high
20438 enough to cover propagation of data from the master server to all slaves.
20440 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
20441 A validity period of newly issued signatures.
20443 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
20444 A period how long before a signature expiration the signature will be refreshed.
20446 @item @code{nsec3?} (default: @code{#f})
20447 When @code{#t}, NSEC3 will be used instead of NSEC.
20449 @item @code{nsec3-iterations} (default: @code{5})
20450 The number of additional times the hashing is performed.
20452 @item @code{nsec3-salt-length} (default: @code{8})
20453 The length of a salt field in octets, which is appended to the original owner
20454 name before hashing.
20456 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
20457 The validity period of newly issued salt field.
20462 @deftp {Data Type} knot-zone-configuration
20463 Data type representing a zone served by Knot.
20464 This type has the following parameters:
20467 @item @code{domain} (default: @code{""})
20468 The domain served by this configuration. It must not be empty.
20470 @item @code{file} (default: @code{""})
20471 The file where this zone is saved. This parameter is ignored by master zones.
20472 Empty means default location that depends on the domain name.
20474 @item @code{zone} (default: @code{(zone-file)})
20475 The content of the zone file. This parameter is ignored by slave zones. It
20476 must contain a zone-file record.
20478 @item @code{master} (default: @code{'()})
20479 A list of master remotes. When empty, this zone is a master. When set, this
20480 zone is a slave. This is a list of remotes identifiers.
20482 @item @code{ddns-master} (default: @code{#f})
20483 The main master. When empty, it defaults to the first master in the list of
20486 @item @code{notify} (default: @code{'()})
20487 A list of slave remote identifiers.
20489 @item @code{acl} (default: @code{'()})
20490 A list of acl identifiers.
20492 @item @code{semantic-checks?} (default: @code{#f})
20493 When set, this adds more semantic checks to the zone.
20495 @item @code{disable-any?} (default: @code{#f})
20496 When set, this forbids queries of the ANY type.
20498 @item @code{zonefile-sync} (default: @code{0})
20499 The delay between a modification in memory and on disk. 0 means immediate
20502 @item @code{zonefile-load} (default: @code{#f})
20503 The way the zone file contents are applied during zone load. Possible values
20507 @item @code{#f} for using the default value from Knot,
20508 @item @code{'none} for not using the zone file at all,
20509 @item @code{'difference} for computing the difference between already available
20510 contents and zone contents and applying it to the current zone contents,
20511 @item @code{'difference-no-serial} for the same as @code{'difference}, but
20512 ignoring the SOA serial in the zone file, while the server takes care of it
20514 @item @code{'whole} for loading zone contents from the zone file.
20517 @item @code{journal-content} (default: @code{#f})
20518 The way the journal is used to store zone and its changes. Possible values
20519 are @code{'none} to not use it at all, @code{'changes} to store changes and
20520 @code{'all} to store contents. @code{#f} does not set this option, so the
20521 default value from Knot is used.
20523 @item @code{max-journal-usage} (default: @code{#f})
20524 The maximum size for the journal on disk. @code{#f} does not set this option,
20525 so the default value from Knot is used.
20527 @item @code{max-journal-depth} (default: @code{#f})
20528 The maximum size of the history. @code{#f} does not set this option, so the
20529 default value from Knot is used.
20531 @item @code{max-zone-size} (default: @code{#f})
20532 The maximum size of the zone file. This limit is enforced for incoming
20533 transfer and updates. @code{#f} does not set this option, so the default
20534 value from Knot is used.
20536 @item @code{dnssec-policy} (default: @code{#f})
20537 A reference to a @code{knot-policy-configuration} record, or the special
20538 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
20541 @item @code{serial-policy} (default: @code{'increment})
20542 A policy between @code{'increment} and @code{'unixtime}.
20547 @deftp {Data Type} knot-configuration
20548 Data type representing the Knot configuration.
20549 This type has the following parameters:
20552 @item @code{knot} (default: @code{knot})
20555 @item @code{run-directory} (default: @code{"/var/run/knot"})
20556 The run directory. This directory will be used for pid file and sockets.
20558 @item @code{includes} (default: @code{'()})
20559 A list of strings or file-like objects denoting other files that must be
20560 included at the top of the configuration file.
20562 @cindex secrets, Knot service
20563 This can be used to manage secrets out-of-band. For example, secret
20564 keys may be stored in an out-of-band file not managed by Guix, and
20565 thus not visible in @file{/gnu/store}---e.g., you could store secret
20566 key configuration in @file{/etc/knot/secrets.conf} and add this file
20567 to the @code{includes} list.
20569 It can also be used to add configuration not supported by this interface.
20571 @item @code{listen-v4} (default: @code{"0.0.0.0"})
20572 An ip address on which to listen.
20574 @item @code{listen-v6} (default: @code{"::"})
20575 An ip address on which to listen.
20577 @item @code{listen-port} (default: @code{53})
20578 A port on which to listen.
20580 @item @code{keys} (default: @code{'()})
20581 The list of knot-key-configuration used by this configuration.
20583 @item @code{acls} (default: @code{'()})
20584 The list of knot-acl-configuration used by this configuration.
20586 @item @code{remotes} (default: @code{'()})
20587 The list of knot-remote-configuration used by this configuration.
20589 @item @code{zones} (default: @code{'()})
20590 The list of knot-zone-configuration used by this configuration.
20595 @subsubheading Dnsmasq Service
20597 @deffn {Scheme Variable} dnsmasq-service-type
20598 This is the type of the dnsmasq service, whose value should be an
20599 @code{dnsmasq-configuration} object as in this example:
20602 (service dnsmasq-service-type
20603 (dnsmasq-configuration
20605 (servers '("192.168.1.1"))))
20609 @deftp {Data Type} dnsmasq-configuration
20610 Data type representing the configuration of dnsmasq.
20613 @item @code{package} (default: @var{dnsmasq})
20614 Package object of the dnsmasq server.
20616 @item @code{no-hosts?} (default: @code{#f})
20617 When true, don't read the hostnames in /etc/hosts.
20619 @item @code{port} (default: @code{53})
20620 The port to listen on. Setting this to zero completely disables DNS
20621 responses, leaving only DHCP and/or TFTP functions.
20623 @item @code{local-service?} (default: @code{#t})
20624 Accept DNS queries only from hosts whose address is on a local subnet,
20625 ie a subnet for which an interface exists on the server.
20627 @item @code{listen-addresses} (default: @code{'()})
20628 Listen on the given IP addresses.
20630 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
20631 The file to read the IP address of the upstream nameservers from.
20633 @item @code{no-resolv?} (default: @code{#f})
20634 When true, don't read @var{resolv-file}.
20636 @item @code{servers} (default: @code{'()})
20637 Specify IP address of upstream servers directly.
20639 @item @code{cache-size} (default: @code{150})
20640 Set the size of dnsmasq's cache. Setting the cache size to zero
20643 @item @code{negative-cache?} (default: @code{#t})
20644 When false, disable negative caching.
20649 @subsubheading ddclient Service
20652 The ddclient service described below runs the ddclient daemon, which takes
20653 care of automatically updating DNS entries for service providers such as
20654 @uref{https://dyn.com/dns/, Dyn}.
20656 The following example show instantiates the service with its default
20660 (service ddclient-service-type)
20663 Note that ddclient needs to access credentials that are stored in a
20664 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
20665 @code{secret-file} below.) You are expected to create this file manually, in
20666 an ``out-of-band'' fashion (you @emph{could} make this file part of the
20667 service configuration, for instance by using @code{plain-file}, but it will be
20668 world-readable @i{via} @file{/gnu/store}.) See the examples in the
20669 @file{share/ddclient} directory of the @code{ddclient} package.
20671 @c %start of fragment
20673 Available @code{ddclient-configuration} fields are:
20675 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
20676 The ddclient package.
20680 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
20681 The period after which ddclient will retry to check IP and domain name.
20683 Defaults to @samp{300}.
20687 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
20688 Use syslog for the output.
20690 Defaults to @samp{#t}.
20694 @deftypevr {@code{ddclient-configuration} parameter} string mail
20697 Defaults to @samp{"root"}.
20701 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
20702 Mail failed update to user.
20704 Defaults to @samp{"root"}.
20708 @deftypevr {@code{ddclient-configuration} parameter} string pid
20709 The ddclient PID file.
20711 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
20715 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
20716 Enable SSL support.
20718 Defaults to @samp{#t}.
20722 @deftypevr {@code{ddclient-configuration} parameter} string user
20723 Specifies the user name or ID that is used when running ddclient
20726 Defaults to @samp{"ddclient"}.
20730 @deftypevr {@code{ddclient-configuration} parameter} string group
20731 Group of the user who will run the ddclient program.
20733 Defaults to @samp{"ddclient"}.
20737 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
20738 Secret file which will be appended to @file{ddclient.conf} file. This
20739 file contains credentials for use by ddclient. You are expected to
20740 create it manually.
20742 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
20746 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
20747 Extra options will be appended to @file{ddclient.conf} file.
20749 Defaults to @samp{()}.
20754 @c %end of fragment
20758 @subsection VPN Services
20759 @cindex VPN (virtual private network)
20760 @cindex virtual private network (VPN)
20762 The @code{(gnu services vpn)} module provides services related to
20763 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
20764 your machine to connect to a VPN, and a @emph{server} service for your machine
20765 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
20767 @deffn {Scheme Procedure} openvpn-client-service @
20768 [#:config (openvpn-client-configuration)]
20770 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
20773 @deffn {Scheme Procedure} openvpn-server-service @
20774 [#:config (openvpn-server-configuration)]
20776 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
20778 Both can be run simultaneously.
20781 @c %automatically generated documentation
20783 Available @code{openvpn-client-configuration} fields are:
20785 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
20786 The OpenVPN package.
20790 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
20791 The OpenVPN pid file.
20793 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
20797 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
20798 The protocol (UDP or TCP) used to open a channel between clients and
20801 Defaults to @samp{udp}.
20805 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
20806 The device type used to represent the VPN connection.
20808 Defaults to @samp{tun}.
20812 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
20813 The certificate authority to check connections against.
20815 Defaults to @samp{"/etc/openvpn/ca.crt"}.
20819 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
20820 The certificate of the machine the daemon is running on. It should be
20821 signed by the authority given in @code{ca}.
20823 Defaults to @samp{"/etc/openvpn/client.crt"}.
20827 @deftypevr {@code{openvpn-client-configuration} parameter} string key
20828 The key of the machine the daemon is running on. It must be the key whose
20829 certificate is @code{cert}.
20831 Defaults to @samp{"/etc/openvpn/client.key"}.
20835 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
20836 Whether to use the lzo compression algorithm.
20838 Defaults to @samp{#t}.
20842 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
20843 Don't re-read key files across SIGUSR1 or --ping-restart.
20845 Defaults to @samp{#t}.
20849 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
20850 Don't close and reopen TUN/TAP device or run up/down scripts across
20851 SIGUSR1 or --ping-restart restarts.
20853 Defaults to @samp{#t}.
20857 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
20860 Defaults to @samp{3}.
20864 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
20865 Add an additional layer of HMAC authentication on top of the TLS control
20866 channel to protect against DoS attacks.
20868 Defaults to @samp{#f}.
20872 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
20873 Whether to check the server certificate has server usage extension.
20875 Defaults to @samp{#t}.
20879 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
20880 Bind to a specific local port number.
20882 Defaults to @samp{#f}.
20886 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
20887 Retry resolving server address.
20889 Defaults to @samp{#t}.
20893 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
20894 A list of remote servers to connect to.
20896 Defaults to @samp{()}.
20898 Available @code{openvpn-remote-configuration} fields are:
20900 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
20903 Defaults to @samp{"my-server"}.
20907 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
20908 Port number the server listens to.
20910 Defaults to @samp{1194}.
20915 @c %end of automatic openvpn-client documentation
20917 @c %automatically generated documentation
20919 Available @code{openvpn-server-configuration} fields are:
20921 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
20922 The OpenVPN package.
20926 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
20927 The OpenVPN pid file.
20929 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
20933 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
20934 The protocol (UDP or TCP) used to open a channel between clients and
20937 Defaults to @samp{udp}.
20941 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
20942 The device type used to represent the VPN connection.
20944 Defaults to @samp{tun}.
20948 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
20949 The certificate authority to check connections against.
20951 Defaults to @samp{"/etc/openvpn/ca.crt"}.
20955 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
20956 The certificate of the machine the daemon is running on. It should be
20957 signed by the authority given in @code{ca}.
20959 Defaults to @samp{"/etc/openvpn/client.crt"}.
20963 @deftypevr {@code{openvpn-server-configuration} parameter} string key
20964 The key of the machine the daemon is running on. It must be the key whose
20965 certificate is @code{cert}.
20967 Defaults to @samp{"/etc/openvpn/client.key"}.
20971 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
20972 Whether to use the lzo compression algorithm.
20974 Defaults to @samp{#t}.
20978 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
20979 Don't re-read key files across SIGUSR1 or --ping-restart.
20981 Defaults to @samp{#t}.
20985 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
20986 Don't close and reopen TUN/TAP device or run up/down scripts across
20987 SIGUSR1 or --ping-restart restarts.
20989 Defaults to @samp{#t}.
20993 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
20996 Defaults to @samp{3}.
21000 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
21001 Add an additional layer of HMAC authentication on top of the TLS control
21002 channel to protect against DoS attacks.
21004 Defaults to @samp{#f}.
21008 @deftypevr {@code{openvpn-server-configuration} parameter} number port
21009 Specifies the port number on which the server listens.
21011 Defaults to @samp{1194}.
21015 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
21016 An ip and mask specifying the subnet inside the virtual network.
21018 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
21022 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
21023 A CIDR notation specifying the IPv6 subnet inside the virtual network.
21025 Defaults to @samp{#f}.
21029 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
21030 The Diffie-Hellman parameters file.
21032 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
21036 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
21037 The file that records client IPs.
21039 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
21043 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
21044 When true, the server will act as a gateway for its clients.
21046 Defaults to @samp{#f}.
21050 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
21051 When true, clients are allowed to talk to each other inside the VPN.
21053 Defaults to @samp{#f}.
21057 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
21058 Causes ping-like messages to be sent back and forth over the link so
21059 that each side knows when the other side has gone down. @code{keepalive}
21060 requires a pair. The first element is the period of the ping sending,
21061 and the second element is the timeout before considering the other side
21066 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
21067 The maximum number of clients.
21069 Defaults to @samp{100}.
21073 @deftypevr {@code{openvpn-server-configuration} parameter} string status
21074 The status file. This file shows a small report on current connection.
21075 It is truncated and rewritten every minute.
21077 Defaults to @samp{"/var/run/openvpn/status"}.
21081 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
21082 The list of configuration for some clients.
21084 Defaults to @samp{()}.
21086 Available @code{openvpn-ccd-configuration} fields are:
21088 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
21091 Defaults to @samp{"client"}.
21095 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
21098 Defaults to @samp{#f}.
21102 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
21105 Defaults to @samp{#f}.
21112 @c %end of automatic openvpn-server documentation
21115 @node Network File System
21116 @subsection Network File System
21119 The @code{(gnu services nfs)} module provides the following services,
21120 which are most commonly used in relation to mounting or exporting
21121 directory trees as @dfn{network file systems} (NFS).
21123 @subsubheading RPC Bind Service
21126 The RPC Bind service provides a facility to map program numbers into
21127 universal addresses.
21128 Many NFS related services use this facility. Hence it is automatically
21129 started when a dependent service starts.
21131 @defvr {Scheme Variable} rpcbind-service-type
21132 A service type for the RPC portmapper daemon.
21136 @deftp {Data Type} rpcbind-configuration
21137 Data type representing the configuration of the RPC Bind Service.
21138 This type has the following parameters:
21140 @item @code{rpcbind} (default: @code{rpcbind})
21141 The rpcbind package to use.
21143 @item @code{warm-start?} (default: @code{#t})
21144 If this parameter is @code{#t}, then the daemon will read a
21145 state file on startup thus reloading state information saved by a previous
21151 @subsubheading Pipefs Pseudo File System
21155 The pipefs file system is used to transfer NFS related data
21156 between the kernel and user space programs.
21158 @defvr {Scheme Variable} pipefs-service-type
21159 A service type for the pipefs pseudo file system.
21162 @deftp {Data Type} pipefs-configuration
21163 Data type representing the configuration of the pipefs pseudo file system service.
21164 This type has the following parameters:
21166 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21167 The directory to which the file system is to be attached.
21172 @subsubheading GSS Daemon Service
21175 @cindex global security system
21177 The @dfn{global security system} (GSS) daemon provides strong security for RPC
21179 Before exchanging RPC requests an RPC client must establish a security
21180 context. Typically this is done using the Kerberos command @command{kinit}
21181 or automatically at login time using PAM services (@pxref{Kerberos Services}).
21183 @defvr {Scheme Variable} gss-service-type
21184 A service type for the Global Security System (GSS) daemon.
21187 @deftp {Data Type} gss-configuration
21188 Data type representing the configuration of the GSS daemon service.
21189 This type has the following parameters:
21191 @item @code{nfs-utils} (default: @code{nfs-utils})
21192 The package in which the @command{rpc.gssd} command is to be found.
21194 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21195 The directory where the pipefs file system is mounted.
21201 @subsubheading IDMAP Daemon Service
21203 @cindex name mapper
21205 The idmap daemon service provides mapping between user IDs and user names.
21206 Typically it is required in order to access file systems mounted via NFSv4.
21208 @defvr {Scheme Variable} idmap-service-type
21209 A service type for the Identity Mapper (IDMAP) daemon.
21212 @deftp {Data Type} idmap-configuration
21213 Data type representing the configuration of the IDMAP daemon service.
21214 This type has the following parameters:
21216 @item @code{nfs-utils} (default: @code{nfs-utils})
21217 The package in which the @command{rpc.idmapd} command is to be found.
21219 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21220 The directory where the pipefs file system is mounted.
21222 @item @code{domain} (default: @code{#f})
21223 The local NFSv4 domain name.
21224 This must be a string or @code{#f}.
21225 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
21230 @node Continuous Integration
21231 @subsection Continuous Integration
21233 @cindex continuous integration
21234 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
21235 continuous integration tool for Guix. It can be used both for development and
21236 for providing substitutes to others (@pxref{Substitutes}).
21238 The @code{(gnu services cuirass)} module provides the following service.
21240 @defvr {Scheme Procedure} cuirass-service-type
21241 The type of the Cuirass service. Its value must be a
21242 @code{cuirass-configuration} object, as described below.
21245 To add build jobs, you have to set the @code{specifications} field of the
21246 configuration. Here is an example of a service that polls the Guix repository
21247 and builds the packages from a manifest. Some of the packages are defined in
21248 the @code{"custom-packages"} input, which is the equivalent of
21249 @code{GUIX_PACKAGE_PATH}.
21252 (define %cuirass-specs
21254 '((#:name . "my-manifest")
21255 (#:load-path-inputs . ("guix"))
21256 (#:package-path-inputs . ("custom-packages"))
21257 (#:proc-input . "guix")
21258 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
21259 (#:proc . cuirass-jobs)
21260 (#:proc-args . ((subset . "manifests")
21261 (systems . ("x86_64-linux"))
21262 (manifests . (("config" . "guix/manifest.scm")))))
21263 (#:inputs . (((#:name . "guix")
21264 (#:url . "git://git.savannah.gnu.org/guix.git")
21265 (#:load-path . ".")
21266 (#:branch . "master")
21267 (#:no-compile? . #t))
21268 ((#:name . "config")
21269 (#:url . "git://git.example.org/config.git")
21270 (#:load-path . ".")
21271 (#:branch . "master")
21272 (#:no-compile? . #t))
21273 ((#:name . "custom-packages")
21274 (#:url . "git://git.example.org/custom-packages.git")
21275 (#:load-path . ".")
21276 (#:branch . "master")
21277 (#:no-compile? . #t)))))))
21279 (service cuirass-service-type
21280 (cuirass-configuration
21281 (specifications %cuirass-specs)))
21284 While information related to build jobs is located directly in the
21285 specifications, global settings for the @command{cuirass} process are
21286 accessible in other @code{cuirass-configuration} fields.
21288 @deftp {Data Type} cuirass-configuration
21289 Data type representing the configuration of Cuirass.
21292 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
21293 Location of the log file.
21295 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
21296 Location of the repository cache.
21298 @item @code{user} (default: @code{"cuirass"})
21299 Owner of the @code{cuirass} process.
21301 @item @code{group} (default: @code{"cuirass"})
21302 Owner's group of the @code{cuirass} process.
21304 @item @code{interval} (default: @code{60})
21305 Number of seconds between the poll of the repositories followed by the
21308 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
21309 Location of sqlite database which contains the build results and previously
21310 added specifications.
21312 @item @code{ttl} (default: @code{(* 30 24 3600)})
21313 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
21314 are registered for build results. This means that build results are protected
21315 from garbage collection for at least @var{ttl} seconds.
21317 @item @code{port} (default: @code{8081})
21318 Port number used by the HTTP server.
21320 @item --listen=@var{host}
21321 Listen on the network interface for @var{host}. The default is to
21322 accept connections from localhost.
21324 @item @code{specifications} (default: @code{#~'()})
21325 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
21326 where a specification is an association list
21327 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
21328 keys are keywords (@code{#:keyword-example}) as shown in the example
21331 @item @code{use-substitutes?} (default: @code{#f})
21332 This allows using substitutes to avoid building every dependencies of a job
21335 @item @code{one-shot?} (default: @code{#f})
21336 Only evaluate specifications and build derivations once.
21338 @item @code{fallback?} (default: @code{#f})
21339 When substituting a pre-built binary fails, fall back to building
21342 @item @code{cuirass} (default: @code{cuirass})
21343 The Cuirass package to use.
21347 @node Power Management Services
21348 @subsection Power Management Services
21351 @cindex power management with TLP
21352 @subsubheading TLP daemon
21354 The @code{(gnu services pm)} module provides a Guix service definition
21355 for the Linux power management tool TLP.
21357 TLP enables various powersaving modes in userspace and kernel.
21358 Contrary to @code{upower-service}, it is not a passive,
21359 monitoring tool, as it will apply custom settings each time a new power
21360 source is detected. More information can be found at
21361 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
21363 @deffn {Scheme Variable} tlp-service-type
21364 The service type for the TLP tool. Its value should be a valid
21365 TLP configuration (see below). To use the default settings, simply
21368 (service tlp-service-type)
21372 By default TLP does not need much configuration but most TLP parameters
21373 can be tweaked using @code{tlp-configuration}.
21375 Each parameter definition is preceded by its type; for example,
21376 @samp{boolean foo} indicates that the @code{foo} parameter
21377 should be specified as a boolean. Types starting with
21378 @code{maybe-} denote parameters that won't show up in TLP config file
21379 when their value is @code{'disabled}.
21381 @c The following documentation was initially generated by
21382 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
21383 @c documentation is better, so we shouldn't hesitate to edit below as
21384 @c needed. However if the change you want to make to this documentation
21385 @c can be done in an automated way, it's probably easier to change
21386 @c (generate-documentation) than to make it below and have to deal with
21387 @c the churn as TLP updates.
21389 Available @code{tlp-configuration} fields are:
21391 @deftypevr {@code{tlp-configuration} parameter} package tlp
21396 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
21397 Set to true if you wish to enable TLP.
21399 Defaults to @samp{#t}.
21403 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
21404 Default mode when no power supply can be detected. Alternatives are AC
21407 Defaults to @samp{"AC"}.
21411 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
21412 Number of seconds Linux kernel has to wait after the disk goes idle,
21413 before syncing on AC.
21415 Defaults to @samp{0}.
21419 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
21420 Same as @code{disk-idle-ac} but on BAT mode.
21422 Defaults to @samp{2}.
21426 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
21427 Dirty pages flushing periodicity, expressed in seconds.
21429 Defaults to @samp{15}.
21433 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
21434 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
21436 Defaults to @samp{60}.
21440 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
21441 CPU frequency scaling governor on AC mode. With intel_pstate driver,
21442 alternatives are powersave and performance. With acpi-cpufreq driver,
21443 alternatives are ondemand, powersave, performance and conservative.
21445 Defaults to @samp{disabled}.
21449 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
21450 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
21452 Defaults to @samp{disabled}.
21456 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
21457 Set the min available frequency for the scaling governor on AC.
21459 Defaults to @samp{disabled}.
21463 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
21464 Set the max available frequency for the scaling governor on AC.
21466 Defaults to @samp{disabled}.
21470 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
21471 Set the min available frequency for the scaling governor on BAT.
21473 Defaults to @samp{disabled}.
21477 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
21478 Set the max available frequency for the scaling governor on BAT.
21480 Defaults to @samp{disabled}.
21484 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
21485 Limit the min P-state to control the power dissipation of the CPU, in AC
21486 mode. Values are stated as a percentage of the available performance.
21488 Defaults to @samp{disabled}.
21492 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
21493 Limit the max P-state to control the power dissipation of the CPU, in AC
21494 mode. Values are stated as a percentage of the available performance.
21496 Defaults to @samp{disabled}.
21500 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
21501 Same as @code{cpu-min-perf-on-ac} on BAT mode.
21503 Defaults to @samp{disabled}.
21507 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
21508 Same as @code{cpu-max-perf-on-ac} on BAT mode.
21510 Defaults to @samp{disabled}.
21514 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
21515 Enable CPU turbo boost feature on AC mode.
21517 Defaults to @samp{disabled}.
21521 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
21522 Same as @code{cpu-boost-on-ac?} on BAT mode.
21524 Defaults to @samp{disabled}.
21528 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
21529 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
21530 used under light load conditions.
21532 Defaults to @samp{#f}.
21536 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
21537 Same as @code{sched-powersave-on-ac?} but on BAT mode.
21539 Defaults to @samp{#t}.
21543 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
21544 Enable Linux kernel NMI watchdog.
21546 Defaults to @samp{#f}.
21550 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
21551 For Linux kernels with PHC patch applied, change CPU voltages. An
21552 example value would be @samp{"F:V F:V F:V F:V"}.
21554 Defaults to @samp{disabled}.
21558 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
21559 Set CPU performance versus energy saving policy on AC. Alternatives are
21560 performance, normal, powersave.
21562 Defaults to @samp{"performance"}.
21566 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
21567 Same as @code{energy-perf-policy-ac} but on BAT mode.
21569 Defaults to @samp{"powersave"}.
21573 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
21578 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
21579 Hard disk advanced power management level.
21583 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
21584 Same as @code{disk-apm-bat} but on BAT mode.
21588 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
21589 Hard disk spin down timeout. One value has to be specified for each
21590 declared hard disk.
21592 Defaults to @samp{disabled}.
21596 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
21597 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
21599 Defaults to @samp{disabled}.
21603 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
21604 Select IO scheduler for disk devices. One value has to be specified for
21605 each declared hard disk. Example alternatives are cfq, deadline and
21608 Defaults to @samp{disabled}.
21612 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
21613 SATA aggressive link power management (ALPM) level. Alternatives are
21614 min_power, medium_power, max_performance.
21616 Defaults to @samp{"max_performance"}.
21620 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
21621 Same as @code{sata-linkpwr-ac} but on BAT mode.
21623 Defaults to @samp{"min_power"}.
21627 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
21628 Exclude specified SATA host devices for link power management.
21630 Defaults to @samp{disabled}.
21634 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
21635 Enable Runtime Power Management for AHCI controller and disks on AC
21638 Defaults to @samp{disabled}.
21642 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
21643 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
21645 Defaults to @samp{disabled}.
21649 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
21650 Seconds of inactivity before disk is suspended.
21652 Defaults to @samp{15}.
21656 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
21657 PCI Express Active State Power Management level. Alternatives are
21658 default, performance, powersave.
21660 Defaults to @samp{"performance"}.
21664 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
21665 Same as @code{pcie-aspm-ac} but on BAT mode.
21667 Defaults to @samp{"powersave"}.
21671 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
21672 Radeon graphics clock speed level. Alternatives are low, mid, high,
21675 Defaults to @samp{"high"}.
21679 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
21680 Same as @code{radeon-power-ac} but on BAT mode.
21682 Defaults to @samp{"low"}.
21686 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
21687 Radeon dynamic power management method (DPM). Alternatives are battery,
21690 Defaults to @samp{"performance"}.
21694 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
21695 Same as @code{radeon-dpm-state-ac} but on BAT mode.
21697 Defaults to @samp{"battery"}.
21701 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
21702 Radeon DPM performance level. Alternatives are auto, low, high.
21704 Defaults to @samp{"auto"}.
21708 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
21709 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
21711 Defaults to @samp{"auto"}.
21715 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
21716 Wifi power saving mode.
21718 Defaults to @samp{#f}.
21722 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
21723 Same as @code{wifi-power-ac?} but on BAT mode.
21725 Defaults to @samp{#t}.
21729 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
21730 Disable wake on LAN.
21732 Defaults to @samp{#t}.
21736 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
21737 Timeout duration in seconds before activating audio power saving on
21738 Intel HDA and AC97 devices. A value of 0 disables power saving.
21740 Defaults to @samp{0}.
21744 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
21745 Same as @code{sound-powersave-ac} but on BAT mode.
21747 Defaults to @samp{1}.
21751 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
21752 Disable controller in powersaving mode on Intel HDA devices.
21754 Defaults to @samp{#t}.
21758 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
21759 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
21760 powered on again by releasing (and reinserting) the eject lever or by
21761 pressing the disc eject button on newer models.
21763 Defaults to @samp{#f}.
21767 @deftypevr {@code{tlp-configuration} parameter} string bay-device
21768 Name of the optical drive device to power off.
21770 Defaults to @samp{"sr0"}.
21774 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
21775 Runtime Power Management for PCI(e) bus devices. Alternatives are on
21778 Defaults to @samp{"on"}.
21782 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
21783 Same as @code{runtime-pm-ac} but on BAT mode.
21785 Defaults to @samp{"auto"}.
21789 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
21790 Runtime Power Management for all PCI(e) bus devices, except blacklisted
21793 Defaults to @samp{#t}.
21797 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
21798 Exclude specified PCI(e) device addresses from Runtime Power Management.
21800 Defaults to @samp{disabled}.
21804 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
21805 Exclude PCI(e) devices assigned to the specified drivers from Runtime
21810 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
21811 Enable USB autosuspend feature.
21813 Defaults to @samp{#t}.
21817 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
21818 Exclude specified devices from USB autosuspend.
21820 Defaults to @samp{disabled}.
21824 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
21825 Exclude WWAN devices from USB autosuspend.
21827 Defaults to @samp{#t}.
21831 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
21832 Include specified devices into USB autosuspend, even if they are already
21833 excluded by the driver or via @code{usb-blacklist-wwan?}.
21835 Defaults to @samp{disabled}.
21839 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
21840 Enable USB autosuspend before shutdown.
21842 Defaults to @samp{disabled}.
21846 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
21847 Restore radio device state (bluetooth, wifi, wwan) from previous
21848 shutdown on system startup.
21850 Defaults to @samp{#f}.
21855 @cindex CPU frequency scaling with thermald
21856 @subsubheading Thermald daemon
21858 The @code{(gnu services pm)} module provides an interface to
21859 thermald, a CPU frequency scaling service which helps prevent overheating.
21861 @defvr {Scheme Variable} thermald-service-type
21862 This is the service type for
21863 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
21864 Thermal Daemon, which is responsible for controlling the thermal state
21865 of processors and preventing overheating.
21868 @deftp {Data Type} thermald-configuration
21869 Data type representing the configuration of @code{thermald-service-type}.
21872 @item @code{ignore-cpuid-check?} (default: @code{#f})
21873 Ignore cpuid check for supported CPU models.
21875 @item @code{thermald} (default: @var{thermald})
21876 Package object of thermald.
21881 @node Audio Services
21882 @subsection Audio Services
21884 The @code{(gnu services audio)} module provides a service to start MPD
21885 (the Music Player Daemon).
21888 @subsubheading Music Player Daemon
21890 The Music Player Daemon (MPD) is a service that can play music while
21891 being controlled from the local machine or over the network by a variety
21894 The following example shows how one might run @code{mpd} as user
21895 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
21898 (service mpd-service-type
21904 @defvr {Scheme Variable} mpd-service-type
21905 The service type for @command{mpd}
21908 @deftp {Data Type} mpd-configuration
21909 Data type representing the configuration of @command{mpd}.
21912 @item @code{user} (default: @code{"mpd"})
21913 The user to run mpd as.
21915 @item @code{music-dir} (default: @code{"~/Music"})
21916 The directory to scan for music files.
21918 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
21919 The directory to store playlists.
21921 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
21922 The location of the music database.
21924 @item @code{state-file} (default: @code{"~/.mpd/state"})
21925 The location of the file that stores current MPD's state.
21927 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
21928 The location of the sticker database.
21930 @item @code{port} (default: @code{"6600"})
21931 The port to run mpd on.
21933 @item @code{address} (default: @code{"any"})
21934 The address that mpd will bind to. To use a Unix domain socket,
21935 an absolute path can be specified here.
21940 @node Virtualization Services
21941 @subsection Virtualization services
21943 The @code{(gnu services virtualization)} module provides services for
21944 the libvirt and virtlog daemons, as well as other virtualization-related
21947 @subsubheading Libvirt daemon
21948 @code{libvirtd} is the server side daemon component of the libvirt
21949 virtualization management system. This daemon runs on host servers
21950 and performs required management tasks for virtualized guests.
21952 @deffn {Scheme Variable} libvirt-service-type
21953 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
21954 Its value must be a @code{libvirt-configuration}.
21957 (service libvirt-service-type
21958 (libvirt-configuration
21959 (unix-sock-group "libvirt")
21960 (tls-port "16555")))
21964 @c Auto-generated with (generate-libvirt-documentation)
21965 Available @code{libvirt-configuration} fields are:
21967 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
21972 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
21973 Flag listening for secure TLS connections on the public TCP/IP port.
21974 must set @code{listen} for this to have any effect.
21976 It is necessary to setup a CA and issue server certificates before using
21979 Defaults to @samp{#t}.
21983 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
21984 Listen for unencrypted TCP connections on the public TCP/IP port. must
21985 set @code{listen} for this to have any effect.
21987 Using the TCP socket requires SASL authentication by default. Only SASL
21988 mechanisms which support data encryption are allowed. This is
21989 DIGEST_MD5 and GSSAPI (Kerberos5)
21991 Defaults to @samp{#f}.
21995 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
21996 Port for accepting secure TLS connections This can be a port number, or
21999 Defaults to @samp{"16514"}.
22003 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
22004 Port for accepting insecure TCP connections This can be a port number,
22007 Defaults to @samp{"16509"}.
22011 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
22012 IP address or hostname used for client connections.
22014 Defaults to @samp{"0.0.0.0"}.
22018 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
22019 Flag toggling mDNS advertisement of the libvirt service.
22021 Alternatively can disable for all services on a host by stopping the
22024 Defaults to @samp{#f}.
22028 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
22029 Default mDNS advertisement name. This must be unique on the immediate
22032 Defaults to @samp{"Virtualization Host <hostname>"}.
22036 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
22037 UNIX domain socket group ownership. This can be used to allow a
22038 'trusted' set of users access to management capabilities without
22041 Defaults to @samp{"root"}.
22045 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
22046 UNIX socket permissions for the R/O socket. This is used for monitoring
22049 Defaults to @samp{"0777"}.
22053 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
22054 UNIX socket permissions for the R/W socket. Default allows only root.
22055 If PolicyKit is enabled on the socket, the default will change to allow
22056 everyone (eg, 0777)
22058 Defaults to @samp{"0770"}.
22062 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
22063 UNIX socket permissions for the admin socket. Default allows only owner
22064 (root), do not change it unless you are sure to whom you are exposing
22067 Defaults to @samp{"0777"}.
22071 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
22072 The directory in which sockets will be found/created.
22074 Defaults to @samp{"/var/run/libvirt"}.
22078 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
22079 Authentication scheme for UNIX read-only sockets. By default socket
22080 permissions allow anyone to connect
22082 Defaults to @samp{"polkit"}.
22086 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
22087 Authentication scheme for UNIX read-write sockets. By default socket
22088 permissions only allow root. If PolicyKit support was compiled into
22089 libvirt, the default will be to use 'polkit' auth.
22091 Defaults to @samp{"polkit"}.
22095 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
22096 Authentication scheme for TCP sockets. If you don't enable SASL, then
22097 all TCP traffic is cleartext. Don't do this outside of a dev/test
22100 Defaults to @samp{"sasl"}.
22104 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
22105 Authentication scheme for TLS sockets. TLS sockets already have
22106 encryption provided by the TLS layer, and limited authentication is done
22109 It is possible to make use of any SASL authentication mechanism as well,
22110 by using 'sasl' for this option
22112 Defaults to @samp{"none"}.
22116 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
22117 API access control scheme.
22119 By default an authenticated user is allowed access to all APIs. Access
22120 drivers can place restrictions on this.
22122 Defaults to @samp{()}.
22126 @deftypevr {@code{libvirt-configuration} parameter} string key-file
22127 Server key file path. If set to an empty string, then no private key is
22130 Defaults to @samp{""}.
22134 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
22135 Server key file path. If set to an empty string, then no certificate is
22138 Defaults to @samp{""}.
22142 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
22143 Server key file path. If set to an empty string, then no CA certificate
22146 Defaults to @samp{""}.
22150 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
22151 Certificate revocation list path. If set to an empty string, then no
22154 Defaults to @samp{""}.
22158 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
22159 Disable verification of our own server certificates.
22161 When libvirtd starts it performs some sanity checks against its own
22164 Defaults to @samp{#f}.
22168 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
22169 Disable verification of client certificates.
22171 Client certificate verification is the primary authentication mechanism.
22172 Any client which does not present a certificate signed by the CA will be
22175 Defaults to @samp{#f}.
22179 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
22180 Whitelist of allowed x509 Distinguished Name.
22182 Defaults to @samp{()}.
22186 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
22187 Whitelist of allowed SASL usernames. The format for username depends on
22188 the SASL authentication mechanism.
22190 Defaults to @samp{()}.
22194 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
22195 Override the compile time default TLS priority string. The default is
22196 usually "NORMAL" unless overridden at build time. Only set this is it
22197 is desired for libvirt to deviate from the global default settings.
22199 Defaults to @samp{"NORMAL"}.
22203 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
22204 Maximum number of concurrent client connections to allow over all
22207 Defaults to @samp{5000}.
22211 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
22212 Maximum length of queue of connections waiting to be accepted by the
22213 daemon. Note, that some protocols supporting retransmission may obey
22214 this so that a later reattempt at connection succeeds.
22216 Defaults to @samp{1000}.
22220 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
22221 Maximum length of queue of accepted but not yet authenticated clients.
22222 Set this to zero to turn this feature off
22224 Defaults to @samp{20}.
22228 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
22229 Number of workers to start up initially.
22231 Defaults to @samp{5}.
22235 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
22236 Maximum number of worker threads.
22238 If the number of active clients exceeds @code{min-workers}, then more
22239 threads are spawned, up to max_workers limit. Typically you'd want
22240 max_workers to equal maximum number of clients allowed.
22242 Defaults to @samp{20}.
22246 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
22247 Number of priority workers. If all workers from above pool are stuck,
22248 some calls marked as high priority (notably domainDestroy) can be
22249 executed in this pool.
22251 Defaults to @samp{5}.
22255 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
22256 Total global limit on concurrent RPC calls.
22258 Defaults to @samp{20}.
22262 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
22263 Limit on concurrent requests from a single client connection. To avoid
22264 one client monopolizing the server this should be a small fraction of
22265 the global max_requests and max_workers parameter.
22267 Defaults to @samp{5}.
22271 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
22272 Same as @code{min-workers} but for the admin interface.
22274 Defaults to @samp{1}.
22278 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
22279 Same as @code{max-workers} but for the admin interface.
22281 Defaults to @samp{5}.
22285 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
22286 Same as @code{max-clients} but for the admin interface.
22288 Defaults to @samp{5}.
22292 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
22293 Same as @code{max-queued-clients} but for the admin interface.
22295 Defaults to @samp{5}.
22299 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
22300 Same as @code{max-client-requests} but for the admin interface.
22302 Defaults to @samp{5}.
22306 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
22307 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22309 Defaults to @samp{3}.
22313 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
22316 A filter allows to select a different logging level for a given category
22317 of logs The format for a filter is one of:
22328 where @code{name} is a string which is matched against the category
22329 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22330 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22331 be a substring of the full category name, in order to match multiple
22332 similar categories), the optional "+" prefix tells libvirt to log stack
22333 trace for each message matching name, and @code{x} is the minimal level
22334 where matching messages should be logged:
22351 Multiple filters can be defined in a single filters statement, they just
22352 need to be separated by spaces.
22354 Defaults to @samp{"3:remote 4:event"}.
22358 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
22361 An output is one of the places to save logging information. The format
22362 for an output can be:
22366 output goes to stderr
22368 @item x:syslog:name
22369 use syslog for the output and use the given name as the ident
22371 @item x:file:file_path
22372 output to a file, with the given filepath
22375 output to journald logging system
22379 In all case the x prefix is the minimal level, acting as a filter
22396 Multiple outputs can be defined, they just need to be separated by
22399 Defaults to @samp{"3:stderr"}.
22403 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
22404 Allows usage of the auditing subsystem to be altered
22408 0: disable all auditing
22411 1: enable auditing, only if enabled on host
22414 2: enable auditing, and exit if disabled on host.
22418 Defaults to @samp{1}.
22422 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
22423 Send audit messages via libvirt logging infrastructure.
22425 Defaults to @samp{#f}.
22429 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
22430 Host UUID. UUID must not have all digits be the same.
22432 Defaults to @samp{""}.
22436 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
22437 Source to read host UUID.
22441 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
22444 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
22448 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
22451 Defaults to @samp{"smbios"}.
22455 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
22456 A keepalive message is sent to a client after @code{keepalive_interval}
22457 seconds of inactivity to check if the client is still responding. If
22458 set to -1, libvirtd will never send keepalive requests; however clients
22459 can still send them and the daemon will send responses.
22461 Defaults to @samp{5}.
22465 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
22466 Maximum number of keepalive messages that are allowed to be sent to the
22467 client without getting any response before the connection is considered
22470 In other words, the connection is automatically closed approximately
22471 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
22472 the last message received from the client. When @code{keepalive-count}
22473 is set to 0, connections will be automatically closed after
22474 @code{keepalive-interval} seconds of inactivity without sending any
22475 keepalive messages.
22477 Defaults to @samp{5}.
22481 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
22482 Same as above but for admin interface.
22484 Defaults to @samp{5}.
22488 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
22489 Same as above but for admin interface.
22491 Defaults to @samp{5}.
22495 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
22496 Timeout for Open vSwitch calls.
22498 The @code{ovs-vsctl} utility is used for the configuration and its
22499 timeout option is set by default to 5 seconds to avoid potential
22500 infinite waits blocking libvirt.
22502 Defaults to @samp{5}.
22506 @c %end of autogenerated docs
22508 @subsubheading Virtlog daemon
22509 The virtlogd service is a server side daemon component of libvirt that is
22510 used to manage logs from virtual machine consoles.
22512 This daemon is not used directly by libvirt client applications, rather it
22513 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
22514 standalone daemon, the main @code{libvirtd} daemon can be restarted without
22515 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
22516 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
22518 @deffn {Scheme Variable} virtlog-service-type
22519 This is the type of the virtlog daemon.
22520 Its value must be a @code{virtlog-configuration}.
22523 (service virtlog-service-type
22524 (virtlog-configuration
22525 (max-clients 1000)))
22529 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
22530 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22532 Defaults to @samp{3}.
22536 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
22539 A filter allows to select a different logging level for a given category
22540 of logs The format for a filter is one of:
22551 where @code{name} is a string which is matched against the category
22552 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22553 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22554 be a substring of the full category name, in order to match multiple
22555 similar categories), the optional "+" prefix tells libvirt to log stack
22556 trace for each message matching name, and @code{x} is the minimal level
22557 where matching messages should be logged:
22574 Multiple filters can be defined in a single filters statement, they just
22575 need to be separated by spaces.
22577 Defaults to @samp{"3:remote 4:event"}.
22581 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
22584 An output is one of the places to save logging information The format
22585 for an output can be:
22589 output goes to stderr
22591 @item x:syslog:name
22592 use syslog for the output and use the given name as the ident
22594 @item x:file:file_path
22595 output to a file, with the given filepath
22598 output to journald logging system
22602 In all case the x prefix is the minimal level, acting as a filter
22619 Multiple outputs can be defined, they just need to be separated by
22622 Defaults to @samp{"3:stderr"}.
22626 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
22627 Maximum number of concurrent client connections to allow over all
22630 Defaults to @samp{1024}.
22634 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
22635 Maximum file size before rolling over.
22637 Defaults to @samp{2MB}
22641 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
22642 Maximum number of backup files to keep.
22644 Defaults to @samp{3}
22648 @subsubheading Transparent Emulation with QEMU
22651 @cindex @code{binfmt_misc}
22652 @code{qemu-binfmt-service-type} provides support for transparent
22653 emulation of program binaries built for different architectures---e.g.,
22654 it allows you to transparently execute an ARMv7 program on an x86_64
22655 machine. It achieves this by combining the @uref{https://www.qemu.org,
22656 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
22658 @defvr {Scheme Variable} qemu-binfmt-service-type
22659 This is the type of the QEMU/binfmt service for transparent emulation.
22660 Its value must be a @code{qemu-binfmt-configuration} object, which
22661 specifies the QEMU package to use as well as the architecture we want to
22665 (service qemu-binfmt-service-type
22666 (qemu-binfmt-configuration
22667 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
22670 In this example, we enable transparent emulation for the ARM and aarch64
22671 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
22672 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
22673 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
22676 @deftp {Data Type} qemu-binfmt-configuration
22677 This is the configuration for the @code{qemu-binfmt} service.
22680 @item @code{platforms} (default: @code{'()})
22681 The list of emulated QEMU platforms. Each item must be a @dfn{platform
22682 object} as returned by @code{lookup-qemu-platforms} (see below).
22684 @item @code{guix-support?} (default: @code{#f})
22685 When it is true, QEMU and all its dependencies are added to the build
22686 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
22687 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
22688 handlers to be used within the build environment, which in turn means
22689 that you can transparently build programs for another architecture.
22691 For example, let's suppose you're on an x86_64 machine and you have this
22695 (service qemu-binfmt-service-type
22696 (qemu-binfmt-configuration
22697 (platforms (lookup-qemu-platforms "arm"))
22698 (guix-support? #t)))
22704 guix build -s armhf-linux inkscape
22708 and it will build Inkscape for ARMv7 @emph{as if it were a native
22709 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
22710 if you'd like to test a package build for an architecture you don't have
22713 @item @code{qemu} (default: @code{qemu})
22714 The QEMU package to use.
22718 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
22719 Return the list of QEMU platform objects corresponding to
22720 @var{platforms}@dots{}. @var{platforms} must be a list of strings
22721 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
22722 @code{"mips64el"}, and so on.
22725 @deffn {Scheme Procedure} qemu-platform? @var{obj}
22726 Return true if @var{obj} is a platform object.
22729 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
22730 Return the name of @var{platform}---a string such as @code{"arm"}.
22733 @node Version Control Services
22734 @subsection Version Control Services
22736 The @code{(gnu services version-control)} module provides a service to
22737 allow remote access to local Git repositories. There are three options:
22738 the @code{git-daemon-service}, which provides access to repositories via
22739 the @code{git://} unsecured TCP-based protocol, extending the
22740 @code{nginx} web server to proxy some requests to
22741 @code{git-http-backend}, or providing a web interface with
22742 @code{cgit-service-type}.
22744 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
22746 Return a service that runs @command{git daemon}, a simple TCP server to
22747 expose repositories over the Git protocol for anonymous access.
22749 The optional @var{config} argument should be a
22750 @code{<git-daemon-configuration>} object, by default it allows read-only
22751 access to exported@footnote{By creating the magic file
22752 "git-daemon-export-ok" in the repository directory.} repositories under
22757 @deftp {Data Type} git-daemon-configuration
22758 Data type representing the configuration for @code{git-daemon-service}.
22761 @item @code{package} (default: @var{git})
22762 Package object of the Git distributed version control system.
22764 @item @code{export-all?} (default: @var{#f})
22765 Whether to allow access for all Git repositories, even if they do not
22766 have the @file{git-daemon-export-ok} file.
22768 @item @code{base-path} (default: @file{/srv/git})
22769 Whether to remap all the path requests as relative to the given path.
22770 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
22771 then if you later try to pull @code{git://example.com/hello.git}, git
22772 daemon will interpret the path as @code{/srv/git/hello.git}.
22774 @item @code{user-path} (default: @var{#f})
22775 Whether to allow @code{~user} notation to be used in requests. When
22776 specified with empty string, requests to @code{git://host/~alice/foo} is
22777 taken as a request to access @code{foo} repository in the home directory
22778 of user @code{alice}. If @var{(user-path "path")} is specified, the
22779 same request is taken as a request to access @code{path/foo} repository
22780 in the home directory of user @code{alice}.
22782 @item @code{listen} (default: @var{'()})
22783 Whether to listen on specific IP addresses or hostnames, defaults to
22786 @item @code{port} (default: @var{#f})
22787 Whether to listen on an alternative port, which defaults to 9418.
22789 @item @code{whitelist} (default: @var{'()})
22790 If not empty, only allow access to this list of directories.
22792 @item @code{extra-options} (default: @var{'()})
22793 Extra options will be passed to @code{git daemon}, please run
22794 @command{man git-daemon} for more information.
22799 The @code{git://} protocol lacks authentication. When you pull from a
22800 repository fetched via @code{git://}, you don't know whether the data you
22801 receive was modified or is even coming from the specified host, and your
22802 connection is subject to eavesdropping. It's better to use an authenticated
22803 and encrypted transport, such as @code{https}. Although Git allows you
22804 to serve repositories using unsophisticated file-based web servers,
22805 there is a faster protocol implemented by the @code{git-http-backend}
22806 program. This program is the back-end of a proper Git web service. It
22807 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
22808 on running the necessary @code{fcgiwrap} daemon.
22810 Guix has a separate configuration data type for serving Git repositories
22813 @deftp {Data Type} git-http-configuration
22814 Data type representing the configuration for @code{git-http-service}.
22817 @item @code{package} (default: @var{git})
22818 Package object of the Git distributed version control system.
22820 @item @code{git-root} (default: @file{/srv/git})
22821 Directory containing the Git repositories to expose to the world.
22823 @item @code{export-all?} (default: @var{#f})
22824 Whether to expose access for all Git repositories in @var{git-root},
22825 even if they do not have the @file{git-daemon-export-ok} file.
22827 @item @code{uri-path} (default: @file{/git/})
22828 Path prefix for Git access. With the default @code{/git/} prefix, this
22829 will map @code{http://@var{server}/git/@var{repo}.git} to
22830 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
22831 with this prefix are not passed on to this Git instance.
22833 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
22834 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
22839 There is no @code{git-http-service-type}, currently; instead you can
22840 create an @code{nginx-location-configuration} from a
22841 @code{git-http-configuration} and then add that location to a web
22844 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
22845 [config=(git-http-configuration)]
22846 Compute an @code{nginx-location-configuration} that corresponds to the
22847 given Git http configuration. An example nginx service definition to
22848 serve the default @file{/srv/git} over HTTPS might be:
22851 (service nginx-service-type
22852 (nginx-configuration
22855 (nginx-server-configuration
22856 (listen '("443 ssl"))
22857 (server-name "git.my-host.org")
22859 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
22860 (ssl-certificate-key
22861 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
22864 (git-http-nginx-location-configuration
22865 (git-http-configuration (uri-path "/"))))))))))
22868 This example assumes that you are using Let's Encrypt to get your TLS
22869 certificate. @xref{Certificate Services}. The default @code{certbot}
22870 service will redirect all HTTP traffic on @code{git.my-host.org} to
22871 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
22872 system services. @xref{Web Services}.
22875 @subsubheading Cgit Service
22877 @cindex Cgit service
22878 @cindex Git, web interface
22879 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
22880 repositories written in C.
22882 The following example will configure the service with default values.
22883 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
22886 (service cgit-service-type)
22889 The @code{file-object} type designates either a file-like object
22890 (@pxref{G-Expressions, file-like objects}) or a string.
22892 @c %start of fragment
22894 Available @code{cgit-configuration} fields are:
22896 @deftypevr {@code{cgit-configuration} parameter} package package
22901 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
22902 NGINX configuration.
22906 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
22907 Specifies a command which will be invoked to format the content of about
22908 pages (both top-level and for each repository).
22910 Defaults to @samp{""}.
22914 @deftypevr {@code{cgit-configuration} parameter} string agefile
22915 Specifies a path, relative to each repository path, which can be used to
22916 specify the date and time of the youngest commit in the repository.
22918 Defaults to @samp{""}.
22922 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
22923 Specifies a command that will be invoked for authenticating repository
22926 Defaults to @samp{""}.
22930 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
22931 Flag which, when set to @samp{age}, enables date ordering in the branch
22932 ref list, and when set @samp{name} enables ordering by branch name.
22934 Defaults to @samp{"name"}.
22938 @deftypevr {@code{cgit-configuration} parameter} string cache-root
22939 Path used to store the cgit cache entries.
22941 Defaults to @samp{"/var/cache/cgit"}.
22945 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
22946 Number which specifies the time-to-live, in minutes, for the cached
22947 version of repository pages accessed with a fixed SHA1.
22949 Defaults to @samp{-1}.
22953 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
22954 Number which specifies the time-to-live, in minutes, for the cached
22955 version of repository pages accessed without a fixed SHA1.
22957 Defaults to @samp{5}.
22961 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
22962 Number which specifies the time-to-live, in minutes, for the cached
22963 version of the repository summary page.
22965 Defaults to @samp{5}.
22969 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
22970 Number which specifies the time-to-live, in minutes, for the cached
22971 version of the repository index page.
22973 Defaults to @samp{5}.
22977 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
22978 Number which specifies the time-to-live, in minutes, for the result of
22979 scanning a path for Git repositories.
22981 Defaults to @samp{15}.
22985 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
22986 Number which specifies the time-to-live, in minutes, for the cached
22987 version of the repository about page.
22989 Defaults to @samp{15}.
22993 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
22994 Number which specifies the time-to-live, in minutes, for the cached
22995 version of snapshots.
22997 Defaults to @samp{5}.
23001 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
23002 The maximum number of entries in the cgit cache. When set to @samp{0},
23003 caching is disabled.
23005 Defaults to @samp{0}.
23009 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
23010 Sort items in the repo list case sensitively.
23012 Defaults to @samp{#t}.
23016 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
23017 List of common prefixes which, when combined with a repository URL,
23018 generates valid clone URLs for the repository.
23020 Defaults to @samp{()}.
23024 @deftypevr {@code{cgit-configuration} parameter} list clone-url
23025 List of @code{clone-url} templates.
23027 Defaults to @samp{()}.
23031 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
23032 Command which will be invoked to format commit messages.
23034 Defaults to @samp{""}.
23038 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
23039 Flag which, when set to @samp{date}, enables strict date ordering in the
23040 commit log, and when set to @samp{topo} enables strict topological
23043 Defaults to @samp{"git log"}.
23047 @deftypevr {@code{cgit-configuration} parameter} file-object css
23048 URL which specifies the css document to include in all cgit pages.
23050 Defaults to @samp{"/share/cgit/cgit.css"}.
23054 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
23055 Specifies a command which will be invoked to format names and email
23056 address of committers, authors, and taggers, as represented in various
23057 places throughout the cgit interface.
23059 Defaults to @samp{""}.
23063 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
23064 Flag which, when set to @samp{#t}, will make cgit generate a HTML
23065 fragment suitable for embedding in other HTML pages.
23067 Defaults to @samp{#f}.
23071 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
23072 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
23073 commit history graph to the left of the commit messages in the
23074 repository log page.
23076 Defaults to @samp{#f}.
23080 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
23081 Flag which, when set to @samp{#t}, allows all filter settings to be
23082 overridden in repository-specific cgitrc files.
23084 Defaults to @samp{#f}.
23088 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
23089 Flag which, when set to @samp{#t}, allows users to follow a file in the
23092 Defaults to @samp{#f}.
23096 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
23097 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
23100 Defaults to @samp{#t}.
23104 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
23105 Flag which, when set to @samp{#t}, will make cgit generate extra links
23106 "summary", "commit", "tree" for each repo in the repository index.
23108 Defaults to @samp{#f}.
23112 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
23113 Flag which, when set to @samp{#t}, will make cgit display the owner of
23114 each repo in the repository index.
23116 Defaults to @samp{#t}.
23120 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
23121 Flag which, when set to @samp{#t}, will make cgit print the number of
23122 modified files for each commit on the repository log page.
23124 Defaults to @samp{#f}.
23128 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
23129 Flag which, when set to @samp{#t}, will make cgit print the number of
23130 added and removed lines for each commit on the repository log page.
23132 Defaults to @samp{#f}.
23136 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
23137 Flag which, when set to @code{#t}, will make cgit display remote
23138 branches in the summary and refs views.
23140 Defaults to @samp{#f}.
23144 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
23145 Flag which, when set to @code{1}, will make cgit use the subject of the
23146 parent commit as link text when generating links to parent commits in
23149 Defaults to @samp{#f}.
23153 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
23154 Flag which, when set to @samp{#t}, will make cgit use the subject of the
23155 parent commit as link text when generating links to parent commits in
23158 Defaults to @samp{#f}.
23162 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
23163 Flag which, when set to @samp{#t}, will make cgit generate linenumber
23164 links for plaintext blobs printed in the tree view.
23166 Defaults to @samp{#t}.
23170 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
23171 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
23172 set any repo specific settings.
23174 Defaults to @samp{#f}.
23178 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
23179 URL used as link to a shortcut icon for cgit.
23181 Defaults to @samp{"/favicon.ico"}.
23185 @deftypevr {@code{cgit-configuration} parameter} string footer
23186 The content of the file specified with this option will be included
23187 verbatim at the bottom of all pages (i.e.@: it replaces the standard
23188 "generated by..."@: message).
23190 Defaults to @samp{""}.
23194 @deftypevr {@code{cgit-configuration} parameter} string head-include
23195 The content of the file specified with this option will be included
23196 verbatim in the HTML HEAD section on all pages.
23198 Defaults to @samp{""}.
23202 @deftypevr {@code{cgit-configuration} parameter} string header
23203 The content of the file specified with this option will be included
23204 verbatim at the top of all pages.
23206 Defaults to @samp{""}.
23210 @deftypevr {@code{cgit-configuration} parameter} file-object include
23211 Name of a configfile to include before the rest of the current config-
23214 Defaults to @samp{""}.
23218 @deftypevr {@code{cgit-configuration} parameter} string index-header
23219 The content of the file specified with this option will be included
23220 verbatim above the repository index.
23222 Defaults to @samp{""}.
23226 @deftypevr {@code{cgit-configuration} parameter} string index-info
23227 The content of the file specified with this option will be included
23228 verbatim below the heading on the repository index page.
23230 Defaults to @samp{""}.
23234 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
23235 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
23236 in the servers timezone.
23238 Defaults to @samp{#f}.
23242 @deftypevr {@code{cgit-configuration} parameter} file-object logo
23243 URL which specifies the source of an image which will be used as a logo
23246 Defaults to @samp{"/share/cgit/cgit.png"}.
23250 @deftypevr {@code{cgit-configuration} parameter} string logo-link
23251 URL loaded when clicking on the cgit logo image.
23253 Defaults to @samp{""}.
23257 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
23258 Command which will be invoked to format the Owner column of the main
23261 Defaults to @samp{""}.
23265 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
23266 Number of items to display in atom feeds view.
23268 Defaults to @samp{10}.
23272 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
23273 Number of entries to list per page in "log" view.
23275 Defaults to @samp{50}.
23279 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
23280 Number of commit message characters to display in "log" view.
23282 Defaults to @samp{80}.
23286 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
23287 Specifies the number of entries to list per page on the repository index
23290 Defaults to @samp{50}.
23294 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
23295 Specifies the maximum number of repo description characters to display
23296 on the repository index page.
23298 Defaults to @samp{80}.
23302 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
23303 Specifies the maximum size of a blob to display HTML for in KBytes.
23305 Defaults to @samp{0}.
23309 @deftypevr {@code{cgit-configuration} parameter} string max-stats
23310 Maximum statistics period. Valid values are @samp{week},@samp{month},
23311 @samp{quarter} and @samp{year}.
23313 Defaults to @samp{""}.
23317 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
23318 Mimetype for the specified filename extension.
23320 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
23321 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
23322 "image/png") (svg "image/svg+xml"))}.
23326 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
23327 Specifies the file to use for automatic mimetype lookup.
23329 Defaults to @samp{""}.
23333 @deftypevr {@code{cgit-configuration} parameter} string module-link
23334 Text which will be used as the formatstring for a hyperlink when a
23335 submodule is printed in a directory listing.
23337 Defaults to @samp{""}.
23341 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
23342 If set to the value @samp{#t} caching will be disabled.
23344 Defaults to @samp{#f}.
23348 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
23349 If set to @samp{#t} showing full author email addresses will be
23352 Defaults to @samp{#f}.
23356 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
23357 Flag which, when set to @samp{#t}, will make cgit omit the standard
23358 header on all pages.
23360 Defaults to @samp{#f}.
23364 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
23365 A list of subdirectories inside of @code{repository-directory}, relative
23366 to it, that should loaded as Git repositories. An empty list means that
23367 all subdirectories will be loaded.
23369 Defaults to @samp{()}.
23373 @deftypevr {@code{cgit-configuration} parameter} file-object readme
23374 Text which will be used as default value for @code{cgit-repo-readme}.
23376 Defaults to @samp{""}.
23380 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
23381 If set to @code{#t} and @code{repository-directory} is enabled, if any
23382 repositories are found with a suffix of @code{.git}, this suffix will be
23383 removed for the URL and name.
23385 Defaults to @samp{#f}.
23389 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
23390 Maximum number of files to consider when detecting renames.
23392 Defaults to @samp{-1}.
23396 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
23397 The way in which repositories in each section are sorted.
23399 Defaults to @samp{""}.
23403 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
23404 Text used as content for the @code{robots} meta-tag.
23406 Defaults to @samp{("noindex" "nofollow")}.
23410 @deftypevr {@code{cgit-configuration} parameter} string root-desc
23411 Text printed below the heading on the repository index page.
23413 Defaults to @samp{"a fast webinterface for the git dscm"}.
23417 @deftypevr {@code{cgit-configuration} parameter} string root-readme
23418 The content of the file specified with this option will be included
23419 verbatim below thef "about" link on the repository index page.
23421 Defaults to @samp{""}.
23425 @deftypevr {@code{cgit-configuration} parameter} string root-title
23426 Text printed as heading on the repository index page.
23428 Defaults to @samp{""}.
23432 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
23433 If set to @samp{#t} and repository-directory is enabled,
23434 repository-directory will recurse into directories whose name starts
23435 with a period. Otherwise, repository-directory will stay away from such
23436 directories, considered as "hidden". Note that this does not apply to
23437 the ".git" directory in non-bare repos.
23439 Defaults to @samp{#f}.
23443 @deftypevr {@code{cgit-configuration} parameter} list snapshots
23444 Text which specifies the default set of snapshot formats that cgit
23445 generates links for.
23447 Defaults to @samp{()}.
23451 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
23452 Name of the directory to scan for repositories (represents
23455 Defaults to @samp{"/srv/git"}.
23459 @deftypevr {@code{cgit-configuration} parameter} string section
23460 The name of the current repository section - all repositories defined
23461 after this option will inherit the current section name.
23463 Defaults to @samp{""}.
23467 @deftypevr {@code{cgit-configuration} parameter} string section-sort
23468 Flag which, when set to @samp{1}, will sort the sections on the
23469 repository listing by name.
23471 Defaults to @samp{""}.
23475 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
23476 A number which, if defined prior to repository-directory, specifies how
23477 many path elements from each repo path to use as a default section name.
23479 Defaults to @samp{0}.
23483 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
23484 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
23487 Defaults to @samp{#f}.
23491 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
23492 Specifies a command which will be invoked to format plaintext blobs in
23495 Defaults to @samp{""}.
23499 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
23500 Specifies the number of branches to display in the repository "summary"
23503 Defaults to @samp{10}.
23507 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
23508 Specifies the number of log entries to display in the repository
23511 Defaults to @samp{10}.
23515 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
23516 Specifies the number of tags to display in the repository "summary"
23519 Defaults to @samp{10}.
23523 @deftypevr {@code{cgit-configuration} parameter} string strict-export
23524 Filename which, if specified, needs to be present within the repository
23525 for cgit to allow access to that repository.
23527 Defaults to @samp{""}.
23531 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
23532 URL which, if specified, will be used as root for all cgit links.
23534 Defaults to @samp{"/"}.
23538 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
23539 A list of @dfn{cgit-repo} records to use with config.
23541 Defaults to @samp{()}.
23543 Available @code{repository-cgit-configuration} fields are:
23545 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
23546 A mask of snapshot formats for this repo that cgit generates links for,
23547 restricted by the global @code{snapshots} setting.
23549 Defaults to @samp{()}.
23553 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
23554 Override the default @code{source-filter}.
23556 Defaults to @samp{""}.
23560 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
23561 The relative URL used to access the repository.
23563 Defaults to @samp{""}.
23567 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
23568 Override the default @code{about-filter}.
23570 Defaults to @samp{""}.
23574 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
23575 Flag which, when set to @samp{age}, enables date ordering in the branch
23576 ref list, and when set to @samp{name} enables ordering by branch name.
23578 Defaults to @samp{""}.
23582 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
23583 A list of URLs which can be used to clone repo.
23585 Defaults to @samp{()}.
23589 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
23590 Override the default @code{commit-filter}.
23592 Defaults to @samp{""}.
23596 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
23597 Flag which, when set to @samp{date}, enables strict date ordering in the
23598 commit log, and when set to @samp{topo} enables strict topological
23601 Defaults to @samp{""}.
23605 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
23606 The name of the default branch for this repository. If no such branch
23607 exists in the repository, the first branch name (when sorted) is used as
23608 default instead. By default branch pointed to by HEAD, or "master" if
23609 there is no suitable HEAD.
23611 Defaults to @samp{""}.
23615 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
23616 The value to show as repository description.
23618 Defaults to @samp{""}.
23622 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
23623 The value to show as repository homepage.
23625 Defaults to @samp{""}.
23629 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
23630 Override the default @code{email-filter}.
23632 Defaults to @samp{""}.
23636 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
23637 A flag which can be used to disable the global setting
23638 @code{enable-commit-graph?}.
23640 Defaults to @samp{disabled}.
23644 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
23645 A flag which can be used to disable the global setting
23646 @code{enable-log-filecount?}.
23648 Defaults to @samp{disabled}.
23652 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
23653 A flag which can be used to disable the global setting
23654 @code{enable-log-linecount?}.
23656 Defaults to @samp{disabled}.
23660 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
23661 Flag which, when set to @code{#t}, will make cgit display remote
23662 branches in the summary and refs views.
23664 Defaults to @samp{disabled}.
23668 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
23669 A flag which can be used to override the global setting
23670 @code{enable-subject-links?}.
23672 Defaults to @samp{disabled}.
23676 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
23677 A flag which can be used to override the global setting
23678 @code{enable-html-serving?}.
23680 Defaults to @samp{disabled}.
23684 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
23685 Flag which, when set to @code{#t}, hides the repository from the
23688 Defaults to @samp{#f}.
23692 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
23693 Flag which, when set to @samp{#t}, ignores the repository.
23695 Defaults to @samp{#f}.
23699 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
23700 URL which specifies the source of an image which will be used as a logo
23701 on this repo’s pages.
23703 Defaults to @samp{""}.
23707 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
23708 URL loaded when clicking on the cgit logo image.
23710 Defaults to @samp{""}.
23714 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
23715 Override the default @code{owner-filter}.
23717 Defaults to @samp{""}.
23721 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
23722 Text which will be used as the formatstring for a hyperlink when a
23723 submodule is printed in a directory listing. The arguments for the
23724 formatstring are the path and SHA1 of the submodule commit.
23726 Defaults to @samp{""}.
23730 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
23731 Text which will be used as the formatstring for a hyperlink when a
23732 submodule with the specified subdirectory path is printed in a directory
23735 Defaults to @samp{()}.
23739 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
23740 Override the default maximum statistics period.
23742 Defaults to @samp{""}.
23746 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
23747 The value to show as repository name.
23749 Defaults to @samp{""}.
23753 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
23754 A value used to identify the owner of the repository.
23756 Defaults to @samp{""}.
23760 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
23761 An absolute path to the repository directory.
23763 Defaults to @samp{""}.
23767 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
23768 A path (relative to repo) which specifies a file to include verbatim as
23769 the "About" page for this repo.
23771 Defaults to @samp{""}.
23775 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
23776 The name of the current repository section - all repositories defined
23777 after this option will inherit the current section name.
23779 Defaults to @samp{""}.
23783 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
23784 Extra options will be appended to cgitrc file.
23786 Defaults to @samp{()}.
23792 @deftypevr {@code{cgit-configuration} parameter} list extra-options
23793 Extra options will be appended to cgitrc file.
23795 Defaults to @samp{()}.
23800 @c %end of fragment
23802 However, it could be that you just want to get a @code{cgitrc} up and
23803 running. In that case, you can pass an @code{opaque-cgit-configuration}
23804 as a record to @code{cgit-service-type}. As its name indicates, an
23805 opaque configuration does not have easy reflective capabilities.
23807 Available @code{opaque-cgit-configuration} fields are:
23809 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
23813 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
23814 The contents of the @code{cgitrc}, as a string.
23817 For example, if your @code{cgitrc} is just the empty string, you
23818 could instantiate a cgit service like this:
23821 (service cgit-service-type
23822 (opaque-cgit-configuration
23826 @subsubheading Gitolite Service
23828 @cindex Gitolite service
23829 @cindex Git, hosting
23830 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
23831 repositories on a central server.
23833 Gitolite can handle multiple repositories and users, and supports flexible
23834 configuration of the permissions for the users on the repositories.
23836 The following example will configure Gitolite using the default @code{git}
23837 user, and the provided SSH public key.
23840 (service gitolite-service-type
23841 (gitolite-configuration
23842 (admin-pubkey (plain-file
23844 "ssh-rsa AAAA... guix@@example.com"))))
23847 Gitolite is configured through a special admin repository which you can clone,
23848 for example, if you setup Gitolite on @code{example.com}, you would run the
23849 following command to clone the admin repository.
23852 git clone git@@example.com:gitolite-admin
23855 When the Gitolite service is activated, the provided @code{admin-pubkey} will
23856 be inserted in to the @file{keydir} directory in the gitolite-admin
23857 repository. If this results in a change in the repository, it will be
23858 committed using the message ``gitolite setup by GNU Guix''.
23860 @deftp {Data Type} gitolite-configuration
23861 Data type representing the configuration for @code{gitolite-service-type}.
23864 @item @code{package} (default: @var{gitolite})
23865 Gitolite package to use.
23867 @item @code{user} (default: @var{git})
23868 User to use for Gitolite. This will be user that you use when accessing
23871 @item @code{group} (default: @var{git})
23872 Group to use for Gitolite.
23874 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
23875 Directory in which to store the Gitolite configuration and repositories.
23877 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
23878 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
23879 representing the configuration for Gitolite.
23881 @item @code{admin-pubkey} (default: @var{#f})
23882 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
23883 setup Gitolite. This will be inserted in to the @file{keydir} directory
23884 within the gitolite-admin repository.
23886 To specify the SSH key as a string, use the @code{plain-file} function.
23889 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
23895 @deftp {Data Type} gitolite-rc-file
23896 Data type representing the Gitolite RC file.
23899 @item @code{umask} (default: @code{#o0077})
23900 This controls the permissions Gitolite sets on the repositories and their
23903 A value like @code{#o0027} will give read access to the group used by Gitolite
23904 (by default: @code{git}). This is necessary when using Gitolite with software
23905 like cgit or gitweb.
23907 @item @code{git-config-keys} (default: @code{""})
23908 Gitolite allows you to set git config values using the "config" keyword. This
23909 setting allows control over the config keys to accept.
23911 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
23912 Set the role names allowed to be used by users running the perms command.
23914 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
23915 This setting controls the commands and features to enable within Gitolite.
23921 @node Game Services
23922 @subsection Game Services
23924 @subsubheading The Battle for Wesnoth Service
23926 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
23927 based tactical strategy game, with several single player campaigns, and
23928 multiplayer games (both networked and local).
23930 @defvar {Scheme Variable} wesnothd-service-type
23931 Service type for the wesnothd service. Its value must be a
23932 @code{wesnothd-configuration} object. To run wesnothd in the default
23933 configuration, instantiate it as:
23936 (service wesnothd-service-type)
23940 @deftp {Data Type} wesnothd-configuration
23941 Data type representing the configuration of @command{wesnothd}.
23944 @item @code{package} (default: @code{wesnoth-server})
23945 The wesnoth server package to use.
23947 @item @code{port} (default: @code{15000})
23948 The port to bind the server to.
23952 @node Miscellaneous Services
23953 @subsection Miscellaneous Services
23955 @cindex fingerprint
23956 @subsubheading Fingerprint Service
23958 The @code{(gnu services authentication)} module provides a DBus service to
23959 read and identify fingerprints via a fingerprint sensor.
23961 @defvr {Scheme Variable} fprintd-service-type
23962 The service type for @command{fprintd}, which provides the fingerprint
23963 reading capability.
23966 (service fprintd-service-type)
23971 @subsubheading System Control Service
23973 The @code{(gnu services sysctl)} provides a service to configure kernel
23974 parameters at boot.
23976 @defvr {Scheme Variable} sysctl-service-type
23977 The service type for @command{sysctl}, which modifies kernel parameters
23978 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
23982 (service sysctl-service-type
23983 (sysctl-configuration
23984 (settings '(("net.ipv4.ip_forward" . "1")))))
23988 @deftp {Data Type} sysctl-configuration
23989 The data type representing the configuration of @command{sysctl}.
23992 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
23993 The @command{sysctl} executable to use.
23995 @item @code{settings} (default: @code{'()})
23996 An association list specifies kernel parameters and their values.
24001 @subsubheading PC/SC Smart Card Daemon Service
24003 The @code{(gnu services security-token)} module provides the following service
24004 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
24005 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
24006 manager that coordinates communications with smart card readers, smart cards
24007 and cryptographic tokens that are connected to the system.
24009 @defvr {Scheme Variable} pcscd-service-type
24010 Service type for the @command{pcscd} service. Its value must be a
24011 @code{pcscd-configuration} object. To run pcscd in the default
24012 configuration, instantiate it as:
24015 (service pcscd-service-type)
24019 @deftp {Data Type} pcscd-configuration
24020 The data type representing the configuration of @command{pcscd}.
24023 @item @code{pcsc-lite} (default: @code{pcsc-lite})
24024 The pcsc-lite package that provides pcscd.
24025 @item @code{usb-drivers} (default: @code{(list ccid)})
24026 List of packages that provide USB drivers to pcscd. Drivers are expected to be
24027 under @file{pcsc/drivers} in the store directory of the package.
24032 @subsubheading Lirc Service
24034 The @code{(gnu services lirc)} module provides the following service.
24036 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
24037 [#:device #f] [#:driver #f] [#:config-file #f] @
24038 [#:extra-options '()]
24039 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
24040 decodes infrared signals from remote controls.
24042 Optionally, @var{device}, @var{driver} and @var{config-file}
24043 (configuration file name) may be specified. See @command{lircd} manual
24046 Finally, @var{extra-options} is a list of additional command-line options
24047 passed to @command{lircd}.
24051 @subsubheading Spice Service
24053 The @code{(gnu services spice)} module provides the following service.
24055 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
24056 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
24057 that enables sharing the clipboard with a vm and setting the guest display
24058 resolution when the graphical console window resizes.
24061 @cindex inputattach
24062 @subsubheading inputattach Service
24064 @cindex tablet input, for Xorg
24065 @cindex touchscreen input, for Xorg
24066 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
24067 use input devices such as Wacom tablets, touchscreens, or joysticks with the
24068 Xorg display server.
24070 @deffn {Scheme Variable} inputattach-service-type
24071 Type of a service that runs @command{inputattach} on a device and
24072 dispatches events from it.
24075 @deftp {Data Type} inputattach-configuration
24077 @item @code{device-type} (default: @code{"wacom"})
24078 The type of device to connect to. Run @command{inputattach --help}, from the
24079 @code{inputattach} package, to see the list of supported device types.
24081 @item @code{device} (default: @code{"/dev/ttyS0"})
24082 The device file to connect to the device.
24084 @item @code{log-file} (default: @code{#f})
24085 If true, this must be the name of a file to log messages to.
24089 @subsection Dictionary Services
24091 The @code{(gnu services dict)} module provides the following service:
24093 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
24094 Return a service that runs the @command{dicod} daemon, an implementation
24095 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
24097 The optional @var{config} argument specifies the configuration for
24098 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
24099 default it serves the GNU Collaborative International Dictonary of English.
24101 You can add @command{open localhost} to your @file{~/.dico} file to make
24102 @code{localhost} the default server for @command{dico} client
24103 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
24106 @deftp {Data Type} dicod-configuration
24107 Data type representing the configuration of dicod.
24110 @item @code{dico} (default: @var{dico})
24111 Package object of the GNU Dico dictionary server.
24113 @item @code{interfaces} (default: @var{'("localhost")})
24114 This is the list of IP addresses and ports and possibly socket file
24115 names to listen to (@pxref{Server Settings, @code{listen} directive,,
24116 dico, GNU Dico Manual}).
24118 @item @code{handlers} (default: @var{'()})
24119 List of @code{<dicod-handler>} objects denoting handlers (module instances).
24121 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
24122 List of @code{<dicod-database>} objects denoting dictionaries to be served.
24126 @deftp {Data Type} dicod-handler
24127 Data type representing a dictionary handler (module instance).
24131 Name of the handler (module instance).
24133 @item @code{module} (default: @var{#f})
24134 Name of the dicod module of the handler (instance). If it is @code{#f},
24135 the module has the same name as the handler.
24136 (@pxref{Modules,,, dico, GNU Dico Manual}).
24138 @item @code{options}
24139 List of strings or gexps representing the arguments for the module handler
24143 @deftp {Data Type} dicod-database
24144 Data type representing a dictionary database.
24148 Name of the database, will be used in DICT commands.
24150 @item @code{handler}
24151 Name of the dicod handler (module instance) used by this database
24152 (@pxref{Handlers,,, dico, GNU Dico Manual}).
24154 @item @code{complex?} (default: @var{#f})
24155 Whether the database configuration complex. The complex configuration
24156 will need a corresponding @code{<dicod-handler>} object, otherwise not.
24158 @item @code{options}
24159 List of strings or gexps representing the arguments for the database
24160 (@pxref{Databases,,, dico, GNU Dico Manual}).
24164 @defvr {Scheme Variable} %dicod-database:gcide
24165 A @code{<dicod-database>} object serving the GNU Collaborative International
24166 Dictionary of English using the @code{gcide} package.
24169 The following is an example @code{dicod-service} configuration.
24172 (dicod-service #:config
24173 (dicod-configuration
24174 (handlers (list (dicod-handler
24178 (list #~(string-append "dbdir=" #$wordnet))))))
24179 (databases (list (dicod-database
24182 (handler "wordnet")
24183 (options '("database=wn")))
24184 %dicod-database:gcide))))
24188 @subsubheading Docker Service
24190 The @code{(gnu services docker)} module provides the following services.
24192 @defvr {Scheme Variable} docker-service-type
24194 This is the type of the service that runs @url{https://www.docker.com,Docker},
24195 a daemon that can execute application bundles (sometimes referred to as
24196 ``containers'') in isolated environments.
24200 @deftp {Data Type} docker-configuration
24201 This is the data type representing the configuration of Docker and Containerd.
24205 @item @code{package} (default: @code{docker})
24206 The Docker package to use.
24208 @item @code{containerd} (default: @var{containerd})
24209 The Containerd package to use.
24215 @subsubheading Auditd Service
24217 The @code{(gnu services auditd)} module provides the following service.
24219 @defvr {Scheme Variable} auditd-service-type
24221 This is the type of the service that runs
24222 @url{https://people.redhat.com/sgrubb/audit/,auditd},
24223 a daemon that tracks security-relevant information on your system.
24225 Examples of things that can be tracked:
24235 Failed login attempts
24242 @command{auditctl} from the @code{audit} package can be used in order
24243 to add or remove events to be tracked (until the next reboot).
24244 In order to permanently track events, put the command line arguments
24245 of auditctl into @file{/etc/audit/audit.rules}.
24246 @command{aureport} from the @code{audit} package can be used in order
24247 to view a report of all recorded events.
24248 The audit daemon usually logs into the directory @file{/var/log/audit}.
24252 @deftp {Data Type} auditd-configuration
24253 This is the data type representing the configuration of auditd.
24257 @item @code{audit} (default: @code{audit})
24258 The audit package to use.
24263 @defvr {Scheme Variable} singularity-service-type
24264 This is the type of the service that allows you to run
24265 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
24266 create and run application bundles (aka. ``containers''). The value for this
24267 service is the Singularity package to use.
24269 The service does not install a daemon; instead, it installs helper programs as
24270 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
24271 @command{singularity run} and similar commands.
24275 @subsubheading Nix service
24277 The @code{(gnu services nix)} module provides the following service.
24279 @defvr {Scheme Variable} nix-service-type
24281 This is the type of the service that runs build daemon of the
24282 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
24286 (use-modules (gnu))
24287 (use-service-modules nix)
24288 (use-package-modules package-management)
24292 (packages (append (list nix)
24295 (services (append (list (service nix-service-type))
24299 After @command{guix system reconfigure} configure Nix for your user:
24302 @item Add a Nix channel and update it. See
24303 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
24305 @item Create a symlink to your profile and activate Nix profile:
24309 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
24310 $ source /run/current-system/profile/etc/profile.d/nix.sh
24315 @node Setuid Programs
24316 @section Setuid Programs
24318 @cindex setuid programs
24319 Some programs need to run with ``root'' privileges, even when they are
24320 launched by unprivileged users. A notorious example is the
24321 @command{passwd} program, which users can run to change their
24322 password, and which needs to access the @file{/etc/passwd} and
24323 @file{/etc/shadow} files---something normally restricted to root, for
24324 obvious security reasons. To address that, these executables are
24325 @dfn{setuid-root}, meaning that they always run with root privileges
24326 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
24327 for more info about the setuid mechanism.)
24329 The store itself @emph{cannot} contain setuid programs: that would be a
24330 security issue since any user on the system can write derivations that
24331 populate the store (@pxref{The Store}). Thus, a different mechanism is
24332 used: instead of changing the setuid bit directly on files that are in
24333 the store, we let the system administrator @emph{declare} which programs
24334 should be setuid root.
24336 The @code{setuid-programs} field of an @code{operating-system}
24337 declaration contains a list of G-expressions denoting the names of
24338 programs to be setuid-root (@pxref{Using the Configuration System}).
24339 For instance, the @command{passwd} program, which is part of the Shadow
24340 package, can be designated by this G-expression (@pxref{G-Expressions}):
24343 #~(string-append #$shadow "/bin/passwd")
24346 A default set of setuid programs is defined by the
24347 @code{%setuid-programs} variable of the @code{(gnu system)} module.
24349 @defvr {Scheme Variable} %setuid-programs
24350 A list of G-expressions denoting common programs that are setuid-root.
24352 The list includes commands such as @command{passwd}, @command{ping},
24353 @command{su}, and @command{sudo}.
24356 Under the hood, the actual setuid programs are created in the
24357 @file{/run/setuid-programs} directory at system activation time. The
24358 files in this directory refer to the ``real'' binaries, which are in the
24361 @node X.509 Certificates
24362 @section X.509 Certificates
24364 @cindex HTTPS, certificates
24365 @cindex X.509 certificates
24367 Web servers available over HTTPS (that is, HTTP over the transport-layer
24368 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
24369 that the client can then use to @emph{authenticate} the server. To do
24370 that, clients verify that the server's certificate is signed by a
24371 so-called @dfn{certificate authority} (CA). But to verify the CA's
24372 signature, clients must have first acquired the CA's certificate.
24374 Web browsers such as GNU@tie{}IceCat include their own set of CA
24375 certificates, such that they are able to verify CA signatures
24378 However, most other programs that can talk HTTPS---@command{wget},
24379 @command{git}, @command{w3m}, etc.---need to be told where CA
24380 certificates can be found.
24382 @cindex @code{nss-certs}
24383 In Guix, this is done by adding a package that provides certificates
24384 to the @code{packages} field of the @code{operating-system} declaration
24385 (@pxref{operating-system Reference}). Guix includes one such package,
24386 @code{nss-certs}, which is a set of CA certificates provided as part of
24387 Mozilla's Network Security Services.
24389 Note that it is @emph{not} part of @code{%base-packages}, so you need to
24390 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
24391 most applications and libraries look for certificates by default, points
24392 to the certificates installed globally.
24394 Unprivileged users, including users of Guix on a foreign distro,
24395 can also install their own certificate package in
24396 their profile. A number of environment variables need to be defined so
24397 that applications and libraries know where to find them. Namely, the
24398 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
24399 variables. Some applications add their own environment variables; for
24400 instance, the Git version control system honors the certificate bundle
24401 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
24402 would typically run something like:
24405 $ guix install nss-certs
24406 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
24407 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24408 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
24411 As another example, R requires the @code{CURL_CA_BUNDLE} environment
24412 variable to point to a certificate bundle, so you would have to run
24413 something like this:
24416 $ guix install nss-certs
24417 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24420 For other applications you may want to look up the required environment
24421 variable in the relevant documentation.
24424 @node Name Service Switch
24425 @section Name Service Switch
24427 @cindex name service switch
24429 The @code{(gnu system nss)} module provides bindings to the
24430 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
24431 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
24432 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
24433 extended with new ``name'' lookup methods for system databases, which
24434 includes host names, service names, user accounts, and more (@pxref{Name
24435 Service Switch, System Databases and Name Service Switch,, libc, The GNU
24436 C Library Reference Manual}).
24438 The NSS configuration specifies, for each system database, which lookup
24439 method is to be used, and how the various methods are chained
24440 together---for instance, under which circumstances NSS should try the
24441 next method in the list. The NSS configuration is given in the
24442 @code{name-service-switch} field of @code{operating-system} declarations
24443 (@pxref{operating-system Reference, @code{name-service-switch}}).
24446 @cindex .local, host name lookup
24447 As an example, the declaration below configures the NSS to use the
24448 @uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
24449 back-end}, which supports host name lookups over multicast DNS (mDNS)
24450 for host names ending in @code{.local}:
24453 (name-service-switch
24454 (hosts (list %files ;first, check /etc/hosts
24456 ;; If the above did not succeed, try
24457 ;; with 'mdns_minimal'.
24459 (name "mdns_minimal")
24461 ;; 'mdns_minimal' is authoritative for
24462 ;; '.local'. When it returns "not found",
24463 ;; no need to try the next methods.
24464 (reaction (lookup-specification
24465 (not-found => return))))
24467 ;; Then fall back to DNS.
24471 ;; Finally, try with the "full" 'mdns'.
24476 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
24477 contains this configuration, so you will not have to type it if all you
24478 want is to have @code{.local} host lookup working.
24480 Note that, in this case, in addition to setting the
24481 @code{name-service-switch} of the @code{operating-system} declaration,
24482 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
24483 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
24484 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
24485 to the name service cache daemon (@pxref{Base Services,
24486 @code{nscd-service}}).
24488 For convenience, the following variables provide typical NSS
24491 @defvr {Scheme Variable} %default-nss
24492 This is the default name service switch configuration, a
24493 @code{name-service-switch} object.
24496 @defvr {Scheme Variable} %mdns-host-lookup-nss
24497 This is the name service switch configuration with support for host name
24498 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
24501 The reference for name service switch configuration is given below. It
24502 is a direct mapping of the configuration file format of the C library , so
24503 please refer to the C library manual for more information (@pxref{NSS
24504 Configuration File,,, libc, The GNU C Library Reference Manual}).
24505 Compared to the configuration file format of libc NSS, it has the advantage
24506 not only of adding this warm parenthetic feel that we like, but also
24507 static checks: you will know about syntax errors and typos as soon as you
24508 run @command{guix system}.
24510 @deftp {Data Type} name-service-switch
24512 This is the data type representation the configuration of libc's name
24513 service switch (NSS). Each field below represents one of the supported
24530 The system databases handled by the NSS. Each of these fields must be a
24531 list of @code{<name-service>} objects (see below).
24535 @deftp {Data Type} name-service
24537 This is the data type representing an actual name service and the
24538 associated lookup action.
24542 A string denoting the name service (@pxref{Services in the NSS
24543 configuration,,, libc, The GNU C Library Reference Manual}).
24545 Note that name services listed here must be visible to nscd. This is
24546 achieved by passing the @code{#:name-services} argument to
24547 @code{nscd-service} the list of packages providing the needed name
24548 services (@pxref{Base Services, @code{nscd-service}}).
24551 An action specified using the @code{lookup-specification} macro
24552 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
24553 Reference Manual}). For example:
24556 (lookup-specification (unavailable => continue)
24557 (success => return))
24562 @node Initial RAM Disk
24563 @section Initial RAM Disk
24566 @cindex initial RAM disk
24567 For bootstrapping purposes, the Linux-Libre kernel is passed an
24568 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
24569 root file system as well as an initialization script. The latter is
24570 responsible for mounting the real root file system, and for loading any
24571 kernel modules that may be needed to achieve that.
24573 The @code{initrd-modules} field of an @code{operating-system}
24574 declaration allows you to specify Linux-libre kernel modules that must
24575 be available in the initrd. In particular, this is where you would list
24576 modules needed to actually drive the hard disk where your root partition
24577 is---although the default value of @code{initrd-modules} should cover
24578 most use cases. For example, assuming you need the @code{megaraid_sas}
24579 module in addition to the default modules to be able to access your root
24580 file system, you would write:
24585 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
24588 @defvr {Scheme Variable} %base-initrd-modules
24589 This is the list of kernel modules included in the initrd by default.
24592 Furthermore, if you need lower-level customization, the @code{initrd}
24593 field of an @code{operating-system} declaration allows
24594 you to specify which initrd you would like to use. The @code{(gnu
24595 system linux-initrd)} module provides three ways to build an initrd: the
24596 high-level @code{base-initrd} procedure and the low-level
24597 @code{raw-initrd} and @code{expression->initrd} procedures.
24599 The @code{base-initrd} procedure is intended to cover most common uses.
24600 For example, if you want to add a bunch of kernel modules to be loaded
24601 at boot time, you can define the @code{initrd} field of the operating
24602 system declaration like this:
24605 (initrd (lambda (file-systems . rest)
24606 ;; Create a standard initrd but set up networking
24607 ;; with the parameters QEMU expects by default.
24608 (apply base-initrd file-systems
24609 #:qemu-networking? #t
24613 The @code{base-initrd} procedure also handles common use cases that
24614 involves using the system as a QEMU guest, or as a ``live'' system with
24615 volatile root file system.
24617 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
24618 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
24619 such as trying to guess which kernel modules and packages should be included
24620 to the initrd. An example use of @code{raw-initrd} is when a user has
24621 a custom Linux kernel configuration and default kernel modules included by
24622 @code{base-initrd} are not available.
24624 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
24625 honors several options passed on the Linux kernel command line
24626 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
24627 @code{-append} option of QEMU), notably:
24630 @item --load=@var{boot}
24631 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
24632 program, once it has mounted the root file system.
24634 Guix uses this option to yield control to a boot program that runs the
24635 service activation programs and then spawns the GNU@tie{}Shepherd, the
24636 initialization system.
24638 @item --root=@var{root}
24639 Mount @var{root} as the root file system. @var{root} can be a
24640 device name like @code{/dev/sda1}, a file system label, or a file system
24643 @item --system=@var{system}
24644 Have @file{/run/booted-system} and @file{/run/current-system} point to
24647 @item modprobe.blacklist=@var{modules}@dots{}
24648 @cindex module, black-listing
24649 @cindex black list, of kernel modules
24650 Instruct the initial RAM disk as well as the @command{modprobe} command
24651 (from the kmod package) to refuse to load @var{modules}. @var{modules}
24652 must be a comma-separated list of module names---e.g.,
24653 @code{usbkbd,9pnet}.
24656 Start a read-eval-print loop (REPL) from the initial RAM disk before it
24657 tries to load kernel modules and to mount the root file system. Our
24658 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
24659 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
24660 Manual}, for more information on Guile's REPL.
24664 Now that you know all the features that initial RAM disks produced by
24665 @code{base-initrd} and @code{raw-initrd} provide,
24666 here is how to use it and customize it further.
24669 @cindex initial RAM disk
24670 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
24671 [#:linux-modules '()] [#:mapped-devices '()] @
24672 [#:keyboard-layout #f] @
24673 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
24674 Return a derivation that builds a raw initrd. @var{file-systems} is
24675 a list of file systems to be mounted by the initrd, possibly in addition to
24676 the root file system specified on the kernel command line via @code{--root}.
24677 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
24678 @var{mapped-devices} is a list of device mappings to realize before
24679 @var{file-systems} are mounted (@pxref{Mapped Devices}).
24680 @var{helper-packages} is a list of packages to be copied in the initrd. It may
24681 include @code{e2fsck/static} or other packages needed by the initrd to check
24682 the root file system.
24684 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24685 the desired console keyboard layout. This is done before @var{mapped-devices}
24686 are set up and before @var{file-systems} are mounted such that, should the
24687 user need to enter a passphrase or use the REPL, this happens using the
24688 intended keyboard layout.
24690 When @var{qemu-networking?} is true, set up networking with the standard QEMU
24691 parameters. When @var{virtio?} is true, load additional modules so that the
24692 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
24694 When @var{volatile-root?} is true, the root file system is writable but any changes
24698 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
24699 [#:mapped-devices '()] [#:keyboard-layout #f] @
24700 [#:qemu-networking? #f] [#:volatile-root? #f] @
24701 [#:linux-modules '()]
24702 Return as a file-like object a generic initrd, with kernel
24703 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
24704 mounted by the initrd, possibly in addition to the root file system specified
24705 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
24706 mappings to realize before @var{file-systems} are mounted.
24708 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24709 the desired console keyboard layout. This is done before @var{mapped-devices}
24710 are set up and before @var{file-systems} are mounted such that, should the
24711 user need to enter a passphrase or use the REPL, this happens using the
24712 intended keyboard layout.
24714 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
24716 The initrd is automatically populated with all the kernel modules necessary
24717 for @var{file-systems} and for the given options. Additional kernel
24718 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
24719 loaded at boot time in the order in which they appear.
24722 Needless to say, the initrds we produce and use embed a
24723 statically-linked Guile, and the initialization program is a Guile
24724 program. That gives a lot of flexibility. The
24725 @code{expression->initrd} procedure builds such an initrd, given the
24726 program to run in that initrd.
24728 @deffn {Scheme Procedure} expression->initrd @var{exp} @
24729 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
24730 Return as a file-like object a Linux initrd (a gzipped cpio archive)
24731 containing @var{guile} and that evaluates @var{exp}, a G-expression,
24732 upon booting. All the derivations referenced by @var{exp} are
24733 automatically copied to the initrd.
24736 @node Bootloader Configuration
24737 @section Bootloader Configuration
24740 @cindex boot loader
24742 The operating system supports multiple bootloaders. The bootloader is
24743 configured using @code{bootloader-configuration} declaration. All the
24744 fields of this structure are bootloader agnostic except for one field,
24745 @code{bootloader} that indicates the bootloader to be configured and
24748 Some of the bootloaders do not honor every field of
24749 @code{bootloader-configuration}. For instance, the extlinux
24750 bootloader does not support themes and thus ignores the @code{theme}
24753 @deftp {Data Type} bootloader-configuration
24754 The type of a bootloader configuration declaration.
24758 @item @code{bootloader}
24759 @cindex EFI, bootloader
24760 @cindex UEFI, bootloader
24761 @cindex BIOS, bootloader
24762 The bootloader to use, as a @code{bootloader} object. For now
24763 @code{grub-bootloader}, @code{grub-efi-bootloader},
24764 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
24766 @vindex grub-efi-bootloader
24767 @code{grub-efi-bootloader} allows to boot on modern systems using the
24768 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
24769 use if the installation image contains a @file{/sys/firmware/efi} directory
24770 when you boot it on your system.
24772 @vindex grub-bootloader
24773 @code{grub-bootloader} allows you to boot in particular Intel-based machines
24774 in ``legacy'' BIOS mode.
24776 @cindex ARM, bootloaders
24777 @cindex AArch64, bootloaders
24778 Available bootloaders are described in @code{(gnu bootloader @dots{})}
24779 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
24780 of bootloaders for a wide range of ARM and AArch64 systems, using the
24781 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
24783 @item @code{target}
24784 This is a string denoting the target onto which to install the
24787 The interpretation depends on the bootloader in question. For
24788 @code{grub-bootloader}, for example, it should be a device name understood by
24789 the bootloader @command{installer} command, such as @code{/dev/sda} or
24790 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
24791 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
24792 system, usually @file{/boot/efi}.
24794 @item @code{menu-entries} (default: @code{()})
24795 A possibly empty list of @code{menu-entry} objects (see below), denoting
24796 entries to appear in the bootloader menu, in addition to the current
24797 system entry and the entry pointing to previous system generations.
24799 @item @code{default-entry} (default: @code{0})
24800 The index of the default boot menu entry. Index 0 is for the entry of the
24803 @item @code{timeout} (default: @code{5})
24804 The number of seconds to wait for keyboard input before booting. Set to
24805 0 to boot immediately, and to -1 to wait indefinitely.
24807 @cindex keyboard layout, for the bootloader
24808 @item @code{keyboard-layout} (default: @code{#f})
24809 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
24810 layout, usually US@tie{}English (``qwerty'').
24812 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
24816 This option is currently ignored by bootloaders other than @code{grub} and
24820 @item @code{theme} (default: @var{#f})
24821 The bootloader theme object describing the theme to use. If no theme
24822 is provided, some bootloaders might use a default theme, that's true
24825 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
24826 The output terminals used for the bootloader boot menu, as a list of
24827 symbols. GRUB accepts the values: @code{console}, @code{serial},
24828 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
24829 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
24830 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
24831 configuration,,, grub,GNU GRUB manual}).
24833 @item @code{terminal-inputs} (default: @code{'()})
24834 The input terminals used for the bootloader boot menu, as a list of
24835 symbols. For GRUB, the default is the native platform terminal as
24836 determined at run-time. GRUB accepts the values: @code{console},
24837 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
24838 @code{usb_keyboard}. This field corresponds to the GRUB variable
24839 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
24842 @item @code{serial-unit} (default: @code{#f})
24843 The serial unit used by the bootloader, as an integer from 0 to 3.
24844 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
24845 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
24847 @item @code{serial-speed} (default: @code{#f})
24848 The speed of the serial interface, as an integer. For GRUB, the
24849 default value is chosen at run-time; currently GRUB chooses
24850 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
24857 Should you want to list additional boot menu entries @i{via} the
24858 @code{menu-entries} field above, you will need to create them with the
24859 @code{menu-entry} form. For example, imagine you want to be able to
24860 boot another distro (hard to imagine!), you can define a menu entry
24865 (label "The Other Distro")
24866 (linux "/boot/old/vmlinux-2.6.32")
24867 (linux-arguments '("root=/dev/sda2"))
24868 (initrd "/boot/old/initrd"))
24873 @deftp {Data Type} menu-entry
24874 The type of an entry in the bootloader menu.
24879 The label to show in the menu---e.g., @code{"GNU"}.
24882 The Linux kernel image to boot, for example:
24885 (file-append linux-libre "/bzImage")
24888 For GRUB, it is also possible to specify a device explicitly in the
24889 file path using GRUB's device naming convention (@pxref{Naming
24890 convention,,, grub, GNU GRUB manual}), for example:
24893 "(hd0,msdos1)/boot/vmlinuz"
24896 If the device is specified explicitly as above, then the @code{device}
24897 field is ignored entirely.
24899 @item @code{linux-arguments} (default: @code{()})
24900 The list of extra Linux kernel command-line arguments---e.g.,
24901 @code{("console=ttyS0")}.
24903 @item @code{initrd}
24904 A G-Expression or string denoting the file name of the initial RAM disk
24905 to use (@pxref{G-Expressions}).
24906 @item @code{device} (default: @code{#f})
24907 The device where the kernel and initrd are to be found---i.e., for GRUB,
24908 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
24910 This may be a file system label (a string), a file system UUID (a
24911 bytevector, @pxref{File Systems}), or @code{#f}, in which case
24912 the bootloader will search the device containing the file specified by
24913 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
24914 must @emph{not} be an OS device name such as @file{/dev/sda1}.
24919 @c FIXME: Write documentation once it's stable.
24920 For now only GRUB has theme support. GRUB themes are created using
24921 the @code{grub-theme} form, which is not documented yet.
24923 @defvr {Scheme Variable} %default-theme
24924 This is the default GRUB theme used by the operating system if no
24925 @code{theme} field is specified in @code{bootloader-configuration}
24928 It comes with a fancy background image displaying the GNU and Guix
24933 @node Invoking guix system
24934 @section Invoking @code{guix system}
24936 Once you have written an operating system declaration as seen in the
24937 previous section, it can be @dfn{instantiated} using the @command{guix
24938 system} command. The synopsis is:
24941 guix system @var{options}@dots{} @var{action} @var{file}
24944 @var{file} must be the name of a file containing an
24945 @code{operating-system} declaration. @var{action} specifies how the
24946 operating system is instantiated. Currently the following values are
24951 Display available service type definitions that match the given regular
24952 expressions, sorted by relevance:
24955 $ guix system search console font
24956 name: console-fonts
24957 location: gnu/services/base.scm:729:2
24958 extends: shepherd-root
24959 description: Install the given fonts on the specified ttys (fonts are
24960 + per virtual console on GNU/Linux). The value of this service is a list
24961 + of tty/font pairs like:
24963 + '(("tty1" . "LatGrkCyr-8x16"))
24967 location: gnu/services/base.scm:1048:2
24968 extends: shepherd-root
24969 description: Provide console login using the `mingetty' program.
24973 location: gnu/services/base.scm:775:2
24975 description: Provide a console log-in service as specified by its
24976 + configuration value, a `login-configuration' object.
24982 As for @command{guix package --search}, the result is written in
24983 @code{recutils} format, which makes it easy to filter the output
24984 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
24987 Build the operating system described in @var{file}, activate it, and
24988 switch to it@footnote{This action (and the related actions
24989 @code{switch-generation} and @code{roll-back}) are usable only on
24990 systems already running Guix System.}.
24992 This effects all the configuration specified in @var{file}: user
24993 accounts, system services, global package list, setuid programs, etc.
24994 The command starts system services specified in @var{file} that are not
24995 currently running; if a service is currently running this command will
24996 arrange for it to be upgraded the next time it is stopped (e.g.@: by
24997 @code{herd stop X} or @code{herd restart X}).
24999 This command creates a new generation whose number is one greater than
25000 the current generation (as reported by @command{guix system
25001 list-generations}). If that generation already exists, it will be
25002 overwritten. This behavior mirrors that of @command{guix package}
25003 (@pxref{Invoking guix package}).
25005 It also adds a bootloader menu entry for the new OS configuration,
25006 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
25007 entries for older configurations to a submenu, allowing you to choose
25008 an older system generation at boot time should you need it.
25011 @c The paragraph below refers to the problem discussed at
25012 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
25013 It is highly recommended to run @command{guix pull} once before you run
25014 @command{guix system reconfigure} for the first time (@pxref{Invoking
25015 guix pull}). Failing to do that you would see an older version of Guix
25016 once @command{reconfigure} has completed.
25019 @item switch-generation
25020 @cindex generations
25021 Switch to an existing system generation. This action atomically
25022 switches the system profile to the specified system generation. It
25023 also rearranges the system's existing bootloader menu entries. It
25024 makes the menu entry for the specified system generation the default,
25025 and it moves the entries for the other generatiors to a submenu, if
25026 supported by the bootloader being used. The next time the system
25027 boots, it will use the specified system generation.
25029 The bootloader itself is not being reinstalled when using this
25030 command. Thus, the installed bootloader is used with an updated
25031 configuration file.
25033 The target generation can be specified explicitly by its generation
25034 number. For example, the following invocation would switch to system
25038 guix system switch-generation 7
25041 The target generation can also be specified relative to the current
25042 generation with the form @code{+N} or @code{-N}, where @code{+3} means
25043 ``3 generations ahead of the current generation,'' and @code{-1} means
25044 ``1 generation prior to the current generation.'' When specifying a
25045 negative value such as @code{-1}, you must precede it with @code{--} to
25046 prevent it from being parsed as an option. For example:
25049 guix system switch-generation -- -1
25052 Currently, the effect of invoking this action is @emph{only} to switch
25053 the system profile to an existing generation and rearrange the
25054 bootloader menu entries. To actually start using the target system
25055 generation, you must reboot after running this action. In the future,
25056 it will be updated to do the same things as @command{reconfigure},
25057 like activating and deactivating services.
25059 This action will fail if the specified generation does not exist.
25062 @cindex rolling back
25063 Switch to the preceding system generation. The next time the system
25064 boots, it will use the preceding system generation. This is the inverse
25065 of @command{reconfigure}, and it is exactly the same as invoking
25066 @command{switch-generation} with an argument of @code{-1}.
25068 Currently, as with @command{switch-generation}, you must reboot after
25069 running this action to actually start using the preceding system
25072 @item delete-generations
25073 @cindex deleting system generations
25074 @cindex saving space
25075 Delete system generations, making them candidates for garbage collection
25076 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
25079 This works in the same way as @command{guix package --delete-generations}
25080 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
25081 arguments, all system generations but the current one are deleted:
25084 guix system delete-generations
25087 You can also select the generations you want to delete. The example below
25088 deletes all the system generations that are more than two month old:
25091 guix system delete-generations 2m
25094 Running this command automatically reinstalls the bootloader with an updated
25095 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
25096 longer lists the generations that have been deleted.
25099 Build the derivation of the operating system, which includes all the
25100 configuration files and programs needed to boot and run the system.
25101 This action does not actually install anything.
25104 Populate the given directory with all the files necessary to run the
25105 operating system specified in @var{file}. This is useful for first-time
25106 installations of Guix System. For instance:
25109 guix system init my-os-config.scm /mnt
25112 copies to @file{/mnt} all the store items required by the configuration
25113 specified in @file{my-os-config.scm}. This includes configuration
25114 files, packages, and so on. It also creates other essential files
25115 needed for the system to operate correctly---e.g., the @file{/etc},
25116 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
25118 This command also installs bootloader on the target specified in
25119 @file{my-os-config}, unless the @option{--no-bootloader} option was
25123 @cindex virtual machine
25125 @anchor{guix system vm}
25126 Build a virtual machine that contains the operating system declared in
25127 @var{file}, and return a script to run that virtual machine (VM).
25130 The @code{vm} action and others below
25131 can use KVM support in the Linux-libre kernel. Specifically, if the
25132 machine has hardware virtualization support, the corresponding
25133 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
25134 must exist and be readable and writable by the user and by the
25135 build users of the daemon (@pxref{Build Environment Setup}).
25138 Arguments given to the script are passed to QEMU as in the example
25139 below, which enables networking and requests 1@tie{}GiB of RAM for the
25143 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -net user
25146 The VM shares its store with the host system.
25148 Additional file systems can be shared between the host and the VM using
25149 the @code{--share} and @code{--expose} command-line options: the former
25150 specifies a directory to be shared with write access, while the latter
25151 provides read-only access to the shared directory.
25153 The example below creates a VM in which the user's home directory is
25154 accessible read-only, and where the @file{/exchange} directory is a
25155 read-write mapping of @file{$HOME/tmp} on the host:
25158 guix system vm my-config.scm \
25159 --expose=$HOME --share=$HOME/tmp=/exchange
25162 On GNU/Linux, the default is to boot directly to the kernel; this has
25163 the advantage of requiring only a very tiny root disk image since the
25164 store of the host can then be mounted.
25166 The @code{--full-boot} option forces a complete boot sequence, starting
25167 with the bootloader. This requires more disk space since a root image
25168 containing at least the kernel, initrd, and bootloader data files must
25169 be created. The @code{--image-size} option can be used to specify the
25172 @cindex System images, creation in various formats
25173 @cindex Creating system images in various formats
25176 @itemx docker-image
25177 Return a virtual machine, disk image, or Docker image of the operating
25178 system declared in @var{file} that stands alone. By default,
25179 @command{guix system} estimates the size of the image needed to store
25180 the system, but you can use the @option{--image-size} option to specify
25181 a value. Docker images are built to contain exactly what they need, so
25182 the @option{--image-size} option is ignored in the case of
25183 @code{docker-image}.
25185 You can specify the root file system type by using the
25186 @option{--file-system-type} option. It defaults to @code{ext4}.
25188 When using @code{vm-image}, the returned image is in qcow2 format, which
25189 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
25190 for more information on how to run the image in a virtual machine.
25192 When using @code{disk-image}, a raw disk image is produced; it can be
25193 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
25194 the device corresponding to a USB stick, one can copy the image to it
25195 using the following command:
25198 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
25201 When using @code{docker-image}, a Docker image is produced. Guix builds
25202 the image from scratch, not from a pre-existing Docker base image. As a
25203 result, it contains @emph{exactly} what you define in the operating
25204 system configuration file. You can then load the image and launch a
25205 Docker container using commands like the following:
25208 image_id="`docker load < guix-system-docker-image.tar.gz`"
25209 container_id="`docker create $image_id`"
25210 docker start $container_id
25213 This command starts a new Docker container from the specified image. It
25214 will boot the Guix system in the usual manner, which means it will
25215 start any services you have defined in the operating system
25216 configuration. You can get an interactive shell running in the container
25217 using @command{docker exec}:
25220 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
25223 Depending on what you run in the Docker container, it
25224 may be necessary to give the container additional permissions. For
25225 example, if you intend to build software using Guix inside of the Docker
25226 container, you may need to pass the @option{--privileged} option to
25227 @code{docker create}.
25230 Return a script to run the operating system declared in @var{file}
25231 within a container. Containers are a set of lightweight isolation
25232 mechanisms provided by the kernel Linux-libre. Containers are
25233 substantially less resource-demanding than full virtual machines since
25234 the kernel, shared objects, and other resources can be shared with the
25235 host system; this also means they provide thinner isolation.
25237 Currently, the script must be run as root in order to support more than
25238 a single user and group. The container shares its store with the host
25241 As with the @code{vm} action (@pxref{guix system vm}), additional file
25242 systems to be shared between the host and container can be specified
25243 using the @option{--share} and @option{--expose} options:
25246 guix system container my-config.scm \
25247 --expose=$HOME --share=$HOME/tmp=/exchange
25251 This option requires Linux-libre 3.19 or newer.
25256 @var{options} can contain any of the common build options (@pxref{Common
25257 Build Options}). In addition, @var{options} can contain one of the
25261 @item --expression=@var{expr}
25262 @itemx -e @var{expr}
25263 Consider the operating-system @var{expr} evaluates to.
25264 This is an alternative to specifying a file which evaluates to an
25266 This is used to generate the Guix system installer @pxref{Building the
25267 Installation Image}).
25269 @item --system=@var{system}
25270 @itemx -s @var{system}
25271 Attempt to build for @var{system} instead of the host system type.
25272 This works as per @command{guix build} (@pxref{Invoking guix build}).
25276 Return the derivation file name of the given operating system without
25279 @item --file-system-type=@var{type}
25280 @itemx -t @var{type}
25281 For the @code{disk-image} action, create a file system of the given
25282 @var{type} on the image.
25284 When this option is omitted, @command{guix system} uses @code{ext4}.
25286 @cindex ISO-9660 format
25287 @cindex CD image format
25288 @cindex DVD image format
25289 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
25290 for burning on CDs and DVDs.
25292 @item --image-size=@var{size}
25293 For the @code{vm-image} and @code{disk-image} actions, create an image
25294 of the given @var{size}. @var{size} may be a number of bytes, or it may
25295 include a unit as a suffix (@pxref{Block size, size specifications,,
25296 coreutils, GNU Coreutils}).
25298 When this option is omitted, @command{guix system} computes an estimate
25299 of the image size as a function of the size of the system declared in
25304 For the @code{container} action, allow containers to access the host network,
25305 that is, do not create a network namespace.
25307 @item --root=@var{file}
25308 @itemx -r @var{file}
25309 Make @var{file} a symlink to the result, and register it as a garbage
25312 @item --skip-checks
25313 Skip pre-installation safety checks.
25315 By default, @command{guix system init} and @command{guix system
25316 reconfigure} perform safety checks: they make sure the file systems that
25317 appear in the @code{operating-system} declaration actually exist
25318 (@pxref{File Systems}), and that any Linux kernel modules that may be
25319 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
25320 RAM Disk}). Passing this option skips these tests altogether.
25323 @cindex on-error strategy
25324 @cindex error strategy
25325 @item --on-error=@var{strategy}
25326 Apply @var{strategy} when an error occurs when reading @var{file}.
25327 @var{strategy} may be one of the following:
25330 @item nothing-special
25331 Report the error concisely and exit. This is the default strategy.
25334 Likewise, but also display a backtrace.
25337 Report the error and enter Guile's debugger. From there, you can run
25338 commands such as @code{,bt} to get a backtrace, @code{,locals} to
25339 display local variable values, and more generally inspect the state of the
25340 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
25341 a list of available debugging commands.
25345 Once you have built, configured, re-configured, and re-re-configured
25346 your Guix installation, you may find it useful to list the operating
25347 system generations available on disk---and that you can choose from the
25348 bootloader boot menu:
25352 @item list-generations
25353 List a summary of each generation of the operating system available on
25354 disk, in a human-readable way. This is similar to the
25355 @option{--list-generations} option of @command{guix package}
25356 (@pxref{Invoking guix package}).
25358 Optionally, one can specify a pattern, with the same syntax that is used
25359 in @command{guix package --list-generations}, to restrict the list of
25360 generations displayed. For instance, the following command displays
25361 generations that are up to 10 days old:
25364 $ guix system list-generations 10d
25369 The @command{guix system} command has even more to offer! The following
25370 sub-commands allow you to visualize how your system services relate to
25373 @anchor{system-extension-graph}
25376 @item extension-graph
25377 Emit in Dot/Graphviz format to standard output the @dfn{service
25378 extension graph} of the operating system defined in @var{file}
25379 (@pxref{Service Composition}, for more information on service
25385 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
25388 produces a PDF file showing the extension relations among services.
25390 @anchor{system-shepherd-graph}
25391 @item shepherd-graph
25392 Emit in Dot/Graphviz format to standard output the @dfn{dependency
25393 graph} of shepherd services of the operating system defined in
25394 @var{file}. @xref{Shepherd Services}, for more information and for an
25399 @node Invoking guix deploy
25400 @section Invoking @code{guix deploy}
25402 We've already seen @code{operating-system} declarations used to manage a
25403 machine's configuration locally. Suppose you need to configure multiple
25404 machines, though---perhaps you're managing a service on the web that's
25405 comprised of several servers. @command{guix deploy} enables you to use those
25406 same @code{operating-system} declarations to manage multiple remote hosts at
25407 once as a logical ``deployment''.
25410 The functionality described in this section is still under development
25411 and is subject to change. Get in touch with us on
25412 @email{guix-devel@@gnu.org}!
25416 guix deploy @var{file}
25419 Such an invocation will deploy the machines that the code within @var{file}
25420 evaluates to. As an example, @var{file} might contain a definition like this:
25423 ;; This is a Guix deployment of a "bare bones" setup, with
25424 ;; no X11 display server, to a machine with an SSH daemon
25425 ;; listening on localhost:2222. A configuration such as this
25426 ;; may be appropriate for virtual machine with ports
25427 ;; forwarded to the host's loopback interface.
25429 (use-service-modules networking ssh)
25430 (use-package-modules bootloaders)
25434 (host-name "gnu-deployed")
25435 (timezone "Etc/UTC")
25436 (bootloader (bootloader-configuration
25437 (bootloader grub-bootloader)
25438 (target "/dev/vda")
25439 (terminal-outputs '(console))))
25440 (file-systems (cons (file-system
25442 (device "/dev/vda1")
25444 %base-file-systems))
25446 (append (list (service dhcp-client-service-type)
25447 (service openssh-service-type
25448 (openssh-configuration
25449 (permit-root-login #t)
25450 (allow-empty-passwords? #t))))
25455 (environment managed-host-environment-type)
25456 (configuration (machine-ssh-configuration
25457 (host-name "localhost")
25458 (identity "./id_rsa")
25462 The file should evaluate to a list of @var{machine} objects. This example,
25463 upon being deployed, will create a new generation on the remote system
25464 realizing the @code{operating-system} declaration @var{%system}.
25465 @var{environment} and @var{configuration} specify how the machine should be
25466 provisioned---that is, how the computing resources should be created and
25467 managed. The above example does not create any resources, as a
25468 @code{'managed-host} is a machine that is already running the Guix system and
25469 available over the network. This is a particularly simple case; a more
25470 complex deployment may involve, for example, starting virtual machines through
25471 a Virtual Private Server (VPS) provider. In such a case, a different
25472 @var{environment} type would be used.
25474 @deftp {Data Type} machine
25475 This is the data type representing a single machine in a heterogeneous Guix
25479 @item @code{system}
25480 The object of the operating system configuration to deploy.
25482 @item @code{environment}
25483 An @code{environment-type} describing how the machine should be provisioned.
25484 At the moment, the only supported value is
25485 @code{managed-host-environment-type}.
25487 @item @code{configuration} (default: @code{#f})
25488 An object describing the configuration for the machine's @code{environment}.
25489 If the @code{environment} has a default configuration, @code{#f} maybe used.
25490 If @code{#f} is used for an environment with no default configuration,
25491 however, an error will be thrown.
25495 @deftp {Data Type} machine-ssh-configuration
25496 This is the data type representing the SSH client parameters for a machine
25497 with an @code{environment} of @code{managed-host-environment-type}.
25500 @item @code{host-name}
25501 @item @code{port} (default: @code{22})
25502 @item @code{user} (default: @code{"root"})
25503 @item @code{identity} (default: @code{#f})
25504 If specified, the path to the SSH private key to use to authenticate with the
25509 @node Running Guix in a VM
25510 @section Running Guix in a Virtual Machine
25512 @cindex virtual machine
25513 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
25515 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
25516 This image is a compressed image in QCOW format. You will first need to
25517 decompress with @command{xz -d}, and then you can pass it to an emulator such
25518 as QEMU (see below for details).
25520 This image boots the Xfce graphical environment and it contains some
25521 commonly-used tools. You can install more software in the image by running
25522 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
25523 also reconfigure the system based on its initial configuration file available
25524 as @file{/etc/config.scm} (@pxref{Using the Configuration System}).
25526 Instead of using this pre-built image, one can also build their own virtual
25527 machine image using @command{guix system vm-image} (@pxref{Invoking guix
25528 system}). The returned image is in qcow2 format, which the
25529 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
25532 If you built your own image, you must copy it out of the store
25533 (@pxref{The Store}) and give yourself permission to write to the copy
25534 before you can use it. When invoking QEMU, you must choose a system
25535 emulator that is suitable for your hardware platform. Here is a minimal
25536 QEMU invocation that will boot the result of @command{guix system
25537 vm-image} on x86_64 hardware:
25540 $ qemu-system-x86_64 \
25541 -net user -net nic,model=virtio \
25542 -enable-kvm -m 512 \
25543 -device virtio-blk,drive=myhd \
25544 -drive if=none,file=/tmp/qemu-image,id=myhd
25547 Here is what each of these options means:
25550 @item qemu-system-x86_64
25551 This specifies the hardware platform to emulate. This should match the
25555 Enable the unprivileged user-mode network stack. The guest OS can
25556 access the host but not vice versa. This is the simplest way to get the
25559 @item -net nic,model=virtio
25560 You must create a network interface of a given model. If you do not
25561 create a NIC, the boot will fail. Assuming your hardware platform is
25562 x86_64, you can get a list of available NIC models by running
25563 @command{qemu-system-x86_64 -net nic,model=help}.
25566 If your system has hardware virtualization extensions, enabling the
25567 virtual machine support (KVM) of the Linux kernel will make things run
25570 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
25572 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
25573 which may be insufficient for some operations.
25575 @item -device virtio-blk,drive=myhd
25576 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
25577 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
25578 better performance than if it were emulating a complete disk drive. See the
25579 QEMU and KVM documentation for more info.
25581 @item -drive if=none,file=/tmp/qemu-image,id=myhd
25582 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
25583 the ``myhd'' drive.
25586 The default @command{run-vm.sh} script that is returned by an invocation of
25587 @command{guix system vm} does not add a @command{-net user} flag by default.
25588 To get network access from within the vm add the @code{(dhcp-client-service)}
25589 to your system definition and start the VM using
25590 @command{`guix system vm config.scm` -net user}. An important caveat of using
25591 @command{-net user} for networking is that @command{ping} will not work, because
25592 it uses the ICMP protocol. You'll have to use a different command to check for
25593 network connectivity, for example @command{guix download}.
25595 @subsection Connecting Through SSH
25599 To enable SSH inside a VM you need to add an SSH server like
25600 @code{openssh-service-type} to your VM (@pxref{Networking Services,
25601 @code{openssh-service-type}}). In addition you need to forward the SSH port,
25602 22 by default, to the host. You can do this with
25605 `guix system vm config.scm` -net user,hostfwd=tcp::10022-:22
25608 To connect to the VM you can run
25611 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
25614 The @command{-p} tells @command{ssh} the port you want to connect to.
25615 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
25616 every time you modify your @command{config.scm} file and the
25617 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
25618 connection to an unknown host every time you connect.
25620 @subsection Using @command{virt-viewer} with Spice
25622 As an alternative to the default @command{qemu} graphical client you can
25623 use the @command{remote-viewer} from the @command{virt-viewer} package. To
25624 connect pass the @command{-spice port=5930,disable-ticketing} flag to
25625 @command{qemu}. See previous section for further information on how to do this.
25627 Spice also allows you to do some nice stuff like share your clipboard with your
25628 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
25631 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
25632 -chardev spicevmc,name=vdagent,id=vdagent
25633 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
25634 name=com.redhat.spice.0
25637 You'll also need to add the @pxref{Miscellaneous Services, Spice service}.
25639 @node Defining Services
25640 @section Defining Services
25642 The previous sections show the available services and how one can combine
25643 them in an @code{operating-system} declaration. But how do we define
25644 them in the first place? And what is a service anyway?
25647 * Service Composition:: The model for composing services.
25648 * Service Types and Services:: Types and services.
25649 * Service Reference:: API reference.
25650 * Shepherd Services:: A particular type of service.
25653 @node Service Composition
25654 @subsection Service Composition
25658 Here we define a @dfn{service} as, broadly, something that extends the
25659 functionality of the operating system. Often a service is a process---a
25660 @dfn{daemon}---started when the system boots: a secure shell server, a
25661 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
25662 whose execution can be triggered by another daemon---e.g., an FTP server
25663 started by @command{inetd} or a D-Bus service activated by
25664 @command{dbus-daemon}. Occasionally, a service does not map to a
25665 daemon. For instance, the ``account'' service collects user accounts
25666 and makes sure they exist when the system runs; the ``udev'' service
25667 collects device management rules and makes them available to the eudev
25668 daemon; the @file{/etc} service populates the @file{/etc} directory
25671 @cindex service extensions
25672 Guix system services are connected by @dfn{extensions}. For instance, the
25673 secure shell service @emph{extends} the Shepherd---the
25674 initialization system, running as PID@tie{}1---by giving it the command
25675 lines to start and stop the secure shell daemon (@pxref{Networking
25676 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
25677 service by passing it its @file{.service} specification, and extends the
25678 udev service by passing it device management rules (@pxref{Desktop
25679 Services, @code{upower-service}}); the Guix daemon service extends the
25680 Shepherd by passing it the command lines to start and stop the daemon,
25681 and extends the account service by passing it a list of required build
25682 user accounts (@pxref{Base Services}).
25684 All in all, services and their ``extends'' relations form a directed
25685 acyclic graph (DAG). If we represent services as boxes and extensions
25686 as arrows, a typical system might provide something like this:
25688 @image{images/service-graph,,5in,Typical service extension graph.}
25690 @cindex system service
25691 At the bottom, we see the @dfn{system service}, which produces the
25692 directory containing everything to run and boot the system, as returned
25693 by the @command{guix system build} command. @xref{Service Reference},
25694 to learn about the other service types shown here.
25695 @xref{system-extension-graph, the @command{guix system extension-graph}
25696 command}, for information on how to generate this representation for a
25697 particular operating system definition.
25699 @cindex service types
25700 Technically, developers can define @dfn{service types} to express these
25701 relations. There can be any number of services of a given type on the
25702 system---for instance, a system running two instances of the GNU secure
25703 shell server (lsh) has two instances of @code{lsh-service-type}, with
25704 different parameters.
25706 The following section describes the programming interface for service
25707 types and services.
25709 @node Service Types and Services
25710 @subsection Service Types and Services
25712 A @dfn{service type} is a node in the DAG described above. Let us start
25713 with a simple example, the service type for the Guix build daemon
25714 (@pxref{Invoking guix-daemon}):
25717 (define guix-service-type
25721 (list (service-extension shepherd-root-service-type guix-shepherd-service)
25722 (service-extension account-service-type guix-accounts)
25723 (service-extension activation-service-type guix-activation)))
25724 (default-value (guix-configuration))))
25728 It defines three things:
25732 A name, whose sole purpose is to make inspection and debugging easier.
25735 A list of @dfn{service extensions}, where each extension designates the
25736 target service type and a procedure that, given the parameters of the
25737 service, returns a list of objects to extend the service of that type.
25739 Every service type has at least one service extension. The only
25740 exception is the @dfn{boot service type}, which is the ultimate service.
25743 Optionally, a default value for instances of this type.
25746 In this example, @code{guix-service-type} extends three services:
25749 @item shepherd-root-service-type
25750 The @code{guix-shepherd-service} procedure defines how the Shepherd
25751 service is extended. Namely, it returns a @code{<shepherd-service>}
25752 object that defines how @command{guix-daemon} is started and stopped
25753 (@pxref{Shepherd Services}).
25755 @item account-service-type
25756 This extension for this service is computed by @code{guix-accounts},
25757 which returns a list of @code{user-group} and @code{user-account}
25758 objects representing the build user accounts (@pxref{Invoking
25761 @item activation-service-type
25762 Here @code{guix-activation} is a procedure that returns a gexp, which is
25763 a code snippet to run at ``activation time''---e.g., when the service is
25767 A service of this type is instantiated like this:
25770 (service guix-service-type
25771 (guix-configuration
25773 (use-substitutes? #f)))
25776 The second argument to the @code{service} form is a value representing
25777 the parameters of this specific service instance.
25778 @xref{guix-configuration-type, @code{guix-configuration}}, for
25779 information about the @code{guix-configuration} data type. When the
25780 value is omitted, the default value specified by
25781 @code{guix-service-type} is used:
25784 (service guix-service-type)
25787 @code{guix-service-type} is quite simple because it extends other
25788 services but is not extensible itself.
25790 @c @subsubsubsection Extensible Service Types
25792 The service type for an @emph{extensible} service looks like this:
25795 (define udev-service-type
25796 (service-type (name 'udev)
25798 (list (service-extension shepherd-root-service-type
25799 udev-shepherd-service)))
25801 (compose concatenate) ;concatenate the list of rules
25802 (extend (lambda (config rules)
25804 (($ <udev-configuration> udev initial-rules)
25805 (udev-configuration
25806 (udev udev) ;the udev package to use
25807 (rules (append initial-rules rules)))))))))
25810 This is the service type for the
25811 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
25812 management daemon}. Compared to the previous example, in addition to an
25813 extension of @code{shepherd-root-service-type}, we see two new fields:
25817 This is the procedure to @dfn{compose} the list of extensions to
25818 services of this type.
25820 Services can extend the udev service by passing it lists of rules; we
25821 compose those extensions simply by concatenating them.
25824 This procedure defines how the value of the service is @dfn{extended} with
25825 the composition of the extensions.
25827 Udev extensions are composed into a list of rules, but the udev service
25828 value is itself a @code{<udev-configuration>} record. So here, we
25829 extend that record by appending the list of rules it contains to the
25830 list of contributed rules.
25833 This is a string giving an overview of the service type. The string can
25834 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
25835 @command{guix system search} command searches these strings and displays
25836 them (@pxref{Invoking guix system}).
25839 There can be only one instance of an extensible service type such as
25840 @code{udev-service-type}. If there were more, the
25841 @code{service-extension} specifications would be ambiguous.
25843 Still here? The next section provides a reference of the programming
25844 interface for services.
25846 @node Service Reference
25847 @subsection Service Reference
25849 We have seen an overview of service types (@pxref{Service Types and
25850 Services}). This section provides a reference on how to manipulate
25851 services and service types. This interface is provided by the
25852 @code{(gnu services)} module.
25854 @deffn {Scheme Procedure} service @var{type} [@var{value}]
25855 Return a new service of @var{type}, a @code{<service-type>} object (see
25856 below.) @var{value} can be any object; it represents the parameters of
25857 this particular service instance.
25859 When @var{value} is omitted, the default value specified by @var{type}
25860 is used; if @var{type} does not specify a default value, an error is
25863 For instance, this:
25866 (service openssh-service-type)
25870 is equivalent to this:
25873 (service openssh-service-type
25874 (openssh-configuration))
25877 In both cases the result is an instance of @code{openssh-service-type}
25878 with the default configuration.
25881 @deffn {Scheme Procedure} service? @var{obj}
25882 Return true if @var{obj} is a service.
25885 @deffn {Scheme Procedure} service-kind @var{service}
25886 Return the type of @var{service}---i.e., a @code{<service-type>} object.
25889 @deffn {Scheme Procedure} service-value @var{service}
25890 Return the value associated with @var{service}. It represents its
25894 Here is an example of how a service is created and manipulated:
25898 (service nginx-service-type
25899 (nginx-configuration
25901 (log-directory log-directory)
25902 (run-directory run-directory)
25903 (file config-file))))
25908 (eq? (service-kind s) nginx-service-type)
25912 The @code{modify-services} form provides a handy way to change the
25913 parameters of some of the services of a list such as
25914 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
25915 evaluates to a list of services. Of course, you could always use
25916 standard list combinators such as @code{map} and @code{fold} to do that
25917 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
25918 @code{modify-services} simply provides a more concise form for this
25921 @deffn {Scheme Syntax} modify-services @var{services} @
25922 (@var{type} @var{variable} => @var{body}) @dots{}
25924 Modify the services listed in @var{services} according to the given
25925 clauses. Each clause has the form:
25928 (@var{type} @var{variable} => @var{body})
25931 where @var{type} is a service type---e.g.,
25932 @code{guix-service-type}---and @var{variable} is an identifier that is
25933 bound within the @var{body} to the service parameters---e.g., a
25934 @code{guix-configuration} instance---of the original service of that
25937 The @var{body} should evaluate to the new service parameters, which will
25938 be used to configure the new service. This new service will replace the
25939 original in the resulting list. Because a service's service parameters
25940 are created using @code{define-record-type*}, you can write a succinct
25941 @var{body} that evaluates to the new service parameters by using the
25942 @code{inherit} feature that @code{define-record-type*} provides.
25944 @xref{Using the Configuration System}, for example usage.
25948 Next comes the programming interface for service types. This is
25949 something you want to know when writing new service definitions, but not
25950 necessarily when simply looking for ways to customize your
25951 @code{operating-system} declaration.
25953 @deftp {Data Type} service-type
25954 @cindex service type
25955 This is the representation of a @dfn{service type} (@pxref{Service Types
25960 This is a symbol, used only to simplify inspection and debugging.
25962 @item @code{extensions}
25963 A non-empty list of @code{<service-extension>} objects (see below).
25965 @item @code{compose} (default: @code{#f})
25966 If this is @code{#f}, then the service type denotes services that cannot
25967 be extended---i.e., services that do not receive ``values'' from other
25970 Otherwise, it must be a one-argument procedure. The procedure is called
25971 by @code{fold-services} and is passed a list of values collected from
25972 extensions. It may return any single value.
25974 @item @code{extend} (default: @code{#f})
25975 If this is @code{#f}, services of this type cannot be extended.
25977 Otherwise, it must be a two-argument procedure: @code{fold-services}
25978 calls it, passing it the initial value of the service as the first
25979 argument and the result of applying @code{compose} to the extension
25980 values as the second argument. It must return a value that is a valid
25981 parameter value for the service instance.
25984 @xref{Service Types and Services}, for examples.
25987 @deffn {Scheme Procedure} service-extension @var{target-type} @
25989 Return a new extension for services of type @var{target-type}.
25990 @var{compute} must be a one-argument procedure: @code{fold-services}
25991 calls it, passing it the value associated with the service that provides
25992 the extension; it must return a valid value for the target service.
25995 @deffn {Scheme Procedure} service-extension? @var{obj}
25996 Return true if @var{obj} is a service extension.
25999 Occasionally, you might want to simply extend an existing service. This
26000 involves creating a new service type and specifying the extension of
26001 interest, which can be verbose; the @code{simple-service} procedure
26002 provides a shorthand for this.
26004 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
26005 Return a service that extends @var{target} with @var{value}. This works
26006 by creating a singleton service type @var{name}, of which the returned
26007 service is an instance.
26009 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
26013 (simple-service 'my-mcron-job mcron-service-type
26014 #~(job '(next-hour (3)) "guix gc -F 2G"))
26018 At the core of the service abstraction lies the @code{fold-services}
26019 procedure, which is responsible for ``compiling'' a list of services
26020 down to a single directory that contains everything needed to boot and
26021 run the system---the directory shown by the @command{guix system build}
26022 command (@pxref{Invoking guix system}). In essence, it propagates
26023 service extensions down the service graph, updating each node parameters
26024 on the way, until it reaches the root node.
26026 @deffn {Scheme Procedure} fold-services @var{services} @
26027 [#:target-type @var{system-service-type}]
26028 Fold @var{services} by propagating their extensions down to the root of
26029 type @var{target-type}; return the root service adjusted accordingly.
26032 Lastly, the @code{(gnu services)} module also defines several essential
26033 service types, some of which are listed below.
26035 @defvr {Scheme Variable} system-service-type
26036 This is the root of the service graph. It produces the system directory
26037 as returned by the @command{guix system build} command.
26040 @defvr {Scheme Variable} boot-service-type
26041 The type of the ``boot service'', which produces the @dfn{boot script}.
26042 The boot script is what the initial RAM disk runs when booting.
26045 @defvr {Scheme Variable} etc-service-type
26046 The type of the @file{/etc} service. This service is used to create
26047 files under @file{/etc} and can be extended by
26048 passing it name/file tuples such as:
26051 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
26054 In this example, the effect would be to add an @file{/etc/issue} file
26055 pointing to the given file.
26058 @defvr {Scheme Variable} setuid-program-service-type
26059 Type for the ``setuid-program service''. This service collects lists of
26060 executable file names, passed as gexps, and adds them to the set of
26061 setuid-root programs on the system (@pxref{Setuid Programs}).
26064 @defvr {Scheme Variable} profile-service-type
26065 Type of the service that populates the @dfn{system profile}---i.e., the
26066 programs under @file{/run/current-system/profile}. Other services can
26067 extend it by passing it lists of packages to add to the system profile.
26071 @node Shepherd Services
26072 @subsection Shepherd Services
26074 @cindex shepherd services
26076 @cindex init system
26077 The @code{(gnu services shepherd)} module provides a way to define
26078 services managed by the GNU@tie{}Shepherd, which is the
26079 initialization system---the first process that is started when the
26080 system boots, also known as PID@tie{}1
26081 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
26083 Services in the Shepherd can depend on each other. For instance, the
26084 SSH daemon may need to be started after the syslog daemon has been
26085 started, which in turn can only happen once all the file systems have
26086 been mounted. The simple operating system defined earlier (@pxref{Using
26087 the Configuration System}) results in a service graph like this:
26089 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
26091 You can actually generate such a graph for any operating system
26092 definition using the @command{guix system shepherd-graph} command
26093 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
26095 The @code{%shepherd-root-service} is a service object representing
26096 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
26097 by passing it lists of @code{<shepherd-service>} objects.
26099 @deftp {Data Type} shepherd-service
26100 The data type representing a service managed by the Shepherd.
26103 @item @code{provision}
26104 This is a list of symbols denoting what the service provides.
26106 These are the names that may be passed to @command{herd start},
26107 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
26108 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
26109 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
26111 @item @code{requirement} (default: @code{'()})
26112 List of symbols denoting the Shepherd services this one depends on.
26114 @cindex one-shot services, for the Shepherd
26115 @item @code{one-shot?} (default: @code{#f})
26116 Whether this service is @dfn{one-shot}. One-shot services stop immediately
26117 after their @code{start} action has completed. @xref{Slots of services,,,
26118 shepherd, The GNU Shepherd Manual}, for more info.
26120 @item @code{respawn?} (default: @code{#t})
26121 Whether to restart the service when it stops, for instance when the
26122 underlying process dies.
26125 @itemx @code{stop} (default: @code{#~(const #f)})
26126 The @code{start} and @code{stop} fields refer to the Shepherd's
26127 facilities to start and stop processes (@pxref{Service De- and
26128 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
26129 G-expressions that get expanded in the Shepherd configuration file
26130 (@pxref{G-Expressions}).
26132 @item @code{actions} (default: @code{'()})
26133 @cindex actions, of Shepherd services
26134 This is a list of @code{shepherd-action} objects (see below) defining
26135 @dfn{actions} supported by the service, in addition to the standard
26136 @code{start} and @code{stop} actions. Actions listed here become available as
26137 @command{herd} sub-commands:
26140 herd @var{action} @var{service} [@var{arguments}@dots{}]
26143 @item @code{auto-start?} (default: @code{#t})
26144 Whether this service should be started automatically by the Shepherd. If it
26145 is @code{#f} the service has to be started manually with @code{herd start}.
26147 @item @code{documentation}
26148 A documentation string, as shown when running:
26151 herd doc @var{service-name}
26154 where @var{service-name} is one of the symbols in @code{provision}
26155 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
26157 @item @code{modules} (default: @code{%default-modules})
26158 This is the list of modules that must be in scope when @code{start} and
26159 @code{stop} are evaluated.
26164 @deftp {Data Type} shepherd-action
26165 This is the data type that defines additional actions implemented by a
26166 Shepherd service (see above).
26170 Symbol naming the action.
26172 @item documentation
26173 This is a documentation string for the action. It can be viewed by running:
26176 herd doc @var{service} action @var{action}
26180 This should be a gexp that evaluates to a procedure of at least one argument,
26181 which is the ``running value'' of the service (@pxref{Slots of services,,,
26182 shepherd, The GNU Shepherd Manual}).
26185 The following example defines an action called @code{say-hello} that kindly
26191 (documentation "Say hi!")
26192 (procedure #~(lambda (running . args)
26193 (format #t "Hello, friend! arguments: ~s\n"
26198 Assuming this action is added to the @code{example} service, then you can do:
26201 # herd say-hello example
26202 Hello, friend! arguments: ()
26203 # herd say-hello example a b c
26204 Hello, friend! arguments: ("a" "b" "c")
26207 This, as you can see, is a fairly sophisticated way to say hello.
26208 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
26212 @defvr {Scheme Variable} shepherd-root-service-type
26213 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
26215 This is the service type that extensions target when they want to create
26216 shepherd services (@pxref{Service Types and Services}, for an example).
26217 Each extension must pass a list of @code{<shepherd-service>}.
26220 @defvr {Scheme Variable} %shepherd-root-service
26221 This service represents PID@tie{}1.
26225 @node Documentation
26226 @chapter Documentation
26228 @cindex documentation, searching for
26229 @cindex searching for documentation
26230 @cindex Info, documentation format
26232 @cindex manual pages
26233 In most cases packages installed with Guix come with documentation.
26234 There are two main documentation formats: ``Info'', a browseable
26235 hypertext format used for GNU software, and ``manual pages'' (or ``man
26236 pages''), the linear documentation format traditionally found on Unix.
26237 Info manuals are accessed with the @command{info} command or with Emacs,
26238 and man pages are accessed using @command{man}.
26240 You can look for documentation of software installed on your system by
26241 keyword. For example, the following command searches for information
26242 about ``TLS'' in Info manuals:
26246 "(emacs)Network Security" -- STARTTLS
26247 "(emacs)Network Security" -- TLS
26248 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
26249 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
26254 The command below searches for the same keyword in man pages:
26258 SSL (7) - OpenSSL SSL/TLS library
26259 certtool (1) - GnuTLS certificate tool
26263 These searches are purely local to your computer so you have the
26264 guarantee that documentation you find corresponds to what you have
26265 actually installed, you can access it off-line, and your privacy is
26268 Once you have these results, you can view the relevant documentation by
26272 $ info "(gnutls)Core TLS API"
26282 Info manuals contain sections and indices as well as hyperlinks like
26283 those found in Web pages. The @command{info} reader (@pxref{Top, Info
26284 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
26285 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
26286 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
26287 Introduction}, for an introduction to Info navigation.
26289 @node Installing Debugging Files
26290 @chapter Installing Debugging Files
26292 @cindex debugging files
26293 Program binaries, as produced by the GCC compilers for instance, are
26294 typically written in the ELF format, with a section containing
26295 @dfn{debugging information}. Debugging information is what allows the
26296 debugger, GDB, to map binary code to source code; it is required to
26297 debug a compiled program in good conditions.
26299 The problem with debugging information is that is takes up a fair amount
26300 of disk space. For example, debugging information for the GNU C Library
26301 weighs in at more than 60 MiB. Thus, as a user, keeping all the
26302 debugging info of all the installed programs is usually not an option.
26303 Yet, space savings should not come at the cost of an impediment to
26304 debugging---especially in the GNU system, which should make it easier
26305 for users to exert their computing freedom (@pxref{GNU Distribution}).
26307 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
26308 mechanism that allows users to get the best of both worlds: debugging
26309 information can be stripped from the binaries and stored in separate
26310 files. GDB is then able to load debugging information from those files,
26311 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
26314 The GNU distribution takes advantage of this by storing debugging
26315 information in the @code{lib/debug} sub-directory of a separate package
26316 output unimaginatively called @code{debug} (@pxref{Packages with
26317 Multiple Outputs}). Users can choose to install the @code{debug} output
26318 of a package when they need it. For instance, the following command
26319 installs the debugging information for the GNU C Library and for GNU
26323 guix install glibc:debug guile:debug
26326 GDB must then be told to look for debug files in the user's profile, by
26327 setting the @code{debug-file-directory} variable (consider setting it
26328 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
26332 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
26335 From there on, GDB will pick up debugging information from the
26336 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
26338 In addition, you will most likely want GDB to be able to show the source
26339 code being debugged. To do that, you will have to unpack the source
26340 code of the package of interest (obtained with @code{guix build
26341 --source}, @pxref{Invoking guix build}), and to point GDB to that source
26342 directory using the @code{directory} command (@pxref{Source Path,
26343 @code{directory},, gdb, Debugging with GDB}).
26345 @c XXX: keep me up-to-date
26346 The @code{debug} output mechanism in Guix is implemented by the
26347 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
26348 opt-in---debugging information is available only for the packages
26349 with definitions explicitly declaring a @code{debug} output. This may be
26350 changed to opt-out in the future if our build farm servers can handle
26351 the load. To check whether a package has a @code{debug} output, use
26352 @command{guix package --list-available} (@pxref{Invoking guix package}).
26355 @node Security Updates
26356 @chapter Security Updates
26358 @cindex security updates
26359 @cindex security vulnerabilities
26360 Occasionally, important security vulnerabilities are discovered in software
26361 packages and must be patched. Guix developers try hard to keep track of
26362 known vulnerabilities and to apply fixes as soon as possible in the
26363 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
26364 containing only security updates.) The @command{guix lint} tool helps
26365 developers find out about vulnerable versions of software packages in the
26370 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
26371 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
26372 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
26376 @xref{Invoking guix lint}, for more information.
26379 As of version @value{VERSION}, the feature described below is considered
26383 Guix follows a functional
26384 package management discipline (@pxref{Introduction}), which implies
26385 that, when a package is changed, @emph{every package that depends on it}
26386 must be rebuilt. This can significantly slow down the deployment of
26387 fixes in core packages such as libc or Bash, since basically the whole
26388 distribution would need to be rebuilt. Using pre-built binaries helps
26389 (@pxref{Substitutes}), but deployment may still take more time than
26393 To address this, Guix implements @dfn{grafts}, a mechanism that allows
26394 for fast deployment of critical updates without the costs associated
26395 with a whole-distribution rebuild. The idea is to rebuild only the
26396 package that needs to be patched, and then to ``graft'' it onto packages
26397 explicitly installed by the user and that were previously referring to
26398 the original package. The cost of grafting is typically very low, and
26399 order of magnitudes lower than a full rebuild of the dependency chain.
26401 @cindex replacements of packages, for grafts
26402 For instance, suppose a security update needs to be applied to Bash.
26403 Guix developers will provide a package definition for the ``fixed''
26404 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
26405 Packages}). Then, the original package definition is augmented with a
26406 @code{replacement} field pointing to the package containing the bug fix:
26413 (replacement bash-fixed)))
26416 From there on, any package depending directly or indirectly on Bash---as
26417 reported by @command{guix gc --requisites} (@pxref{Invoking guix
26418 gc})---that is installed is automatically ``rewritten'' to refer to
26419 @code{bash-fixed} instead of @code{bash}. This grafting process takes
26420 time proportional to the size of the package, usually less than a
26421 minute for an ``average'' package on a recent machine. Grafting is
26422 recursive: when an indirect dependency requires grafting, then grafting
26423 ``propagates'' up to the package that the user is installing.
26425 Currently, the length of the name and version of the graft and that of
26426 the package it replaces (@code{bash-fixed} and @code{bash} in the example
26427 above) must be equal. This restriction mostly comes from the fact that
26428 grafting works by patching files, including binary files, directly.
26429 Other restrictions may apply: for instance, when adding a graft to a
26430 package providing a shared library, the original shared library and its
26431 replacement must have the same @code{SONAME} and be binary-compatible.
26433 The @option{--no-grafts} command-line option allows you to forcefully
26434 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
26438 guix build bash --no-grafts
26442 returns the store file name of the original Bash, whereas:
26449 returns the store file name of the ``fixed'', replacement Bash. This
26450 allows you to distinguish between the two variants of Bash.
26452 To verify which Bash your whole profile refers to, you can run
26453 (@pxref{Invoking guix gc}):
26456 guix gc -R `readlink -f ~/.guix-profile` | grep bash
26460 @dots{} and compare the store file names that you get with those above.
26461 Likewise for a complete Guix system generation:
26464 guix gc -R `guix system build my-config.scm` | grep bash
26467 Lastly, to check which Bash running processes are using, you can use the
26468 @command{lsof} command:
26471 lsof | grep /gnu/store/.*bash
26475 @node Bootstrapping
26476 @chapter Bootstrapping
26478 @c Adapted from the ELS 2013 paper.
26480 @cindex bootstrapping
26482 Bootstrapping in our context refers to how the distribution gets built
26483 ``from nothing''. Remember that the build environment of a derivation
26484 contains nothing but its declared inputs (@pxref{Introduction}). So
26485 there's an obvious chicken-and-egg problem: how does the first package
26486 get built? How does the first compiler get compiled? Note that this is
26487 a question of interest only to the curious hacker, not to the regular
26488 user, so you can shamelessly skip this section if you consider yourself
26489 a ``regular user''.
26491 @cindex bootstrap binaries
26492 The GNU system is primarily made of C code, with libc at its core. The
26493 GNU build system itself assumes the availability of a Bourne shell and
26494 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
26495 `grep'. Furthermore, build programs---programs that run
26496 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
26497 (@pxref{Derivations}). Consequently, to be able to build anything at
26498 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
26499 Binutils, libc, and the other packages mentioned above---the
26500 @dfn{bootstrap binaries}.
26502 These bootstrap binaries are ``taken for granted'', though we can also
26503 re-create them if needed (more on that later).
26505 @unnumberedsec Preparing to Use the Bootstrap Binaries
26507 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
26508 @c large image, it's hard to scroll. Oh well.
26509 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
26511 The figure above shows the very beginning of the dependency graph of the
26512 distribution, corresponding to the package definitions of the @code{(gnu
26513 packages bootstrap)} module. A similar figure can be generated with
26514 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
26517 guix graph -t derivation \
26518 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
26522 At this level of detail, things are
26523 slightly complex. First, Guile itself consists of an ELF executable,
26524 along with many source and compiled Scheme files that are dynamically
26525 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
26526 tarball shown in this graph. This tarball is part of Guix's ``source''
26527 distribution, and gets inserted into the store with @code{add-to-store}
26528 (@pxref{The Store}).
26530 But how do we write a derivation that unpacks this tarball and adds it
26531 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
26532 derivation---the first one that gets built---uses @code{bash} as its
26533 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
26534 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
26535 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
26536 the Guix source distribution, whose sole purpose is to allow the Guile
26537 tarball to be unpacked.
26539 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
26540 Guile that can be used to run subsequent build programs. Its first task
26541 is to download tarballs containing the other pre-built binaries---this
26542 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
26543 @code{ftp-client.scm} are used for this purpose. The
26544 @code{module-import.drv} derivations import those modules in a directory
26545 in the store, using the original layout. The
26546 @code{module-import-compiled.drv} derivations compile those modules, and
26547 write them in an output directory with the right layout. This
26548 corresponds to the @code{#:modules} argument of
26549 @code{build-expression->derivation} (@pxref{Derivations}).
26551 Finally, the various tarballs are unpacked by the
26552 derivations @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv},
26553 etc., at which point we have a working C tool chain.
26556 @unnumberedsec Building the Build Tools
26558 Bootstrapping is complete when we have a full tool chain that does not
26559 depend on the pre-built bootstrap tools discussed above. This
26560 no-dependency requirement is verified by checking whether the files of
26561 the final tool chain contain references to the @file{/gnu/store}
26562 directories of the bootstrap inputs. The process that leads to this
26563 ``final'' tool chain is described by the package definitions found in
26564 the @code{(gnu packages commencement)} module.
26566 The @command{guix graph} command allows us to ``zoom out'' compared to
26567 the graph above, by looking at the level of package objects instead of
26568 individual derivations---remember that a package may translate to
26569 several derivations, typically one derivation to download its source,
26570 one to build the Guile modules it needs, and one to actually build the
26571 package from source. The command:
26574 guix graph -t bag \
26575 -e '(@@@@ (gnu packages commencement)
26576 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
26580 produces the dependency graph leading to the ``final'' C
26581 library@footnote{You may notice the @code{glibc-intermediate} label,
26582 suggesting that it is not @emph{quite} final, but as a good
26583 approximation, we will consider it final.}, depicted below.
26585 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
26587 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
26588 The first tool that gets built with the bootstrap binaries is
26589 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
26590 for all the following packages. From there Findutils and Diffutils get
26593 Then come the first-stage Binutils and GCC, built as pseudo cross
26594 tools---i.e., with @code{--target} equal to @code{--host}. They are
26595 used to build libc. Thanks to this cross-build trick, this libc is
26596 guaranteed not to hold any reference to the initial tool chain.
26598 From there the final Binutils and GCC (not shown above) are built.
26600 from the final Binutils, and links programs against the just-built libc.
26601 This tool chain is used to build the other packages used by Guix and by
26602 the GNU Build System: Guile, Bash, Coreutils, etc.
26604 And voilà! At this point we have the complete set of build tools that
26605 the GNU Build System expects. These are in the @code{%final-inputs}
26606 variable of the @code{(gnu packages commencement)} module, and are
26607 implicitly used by any package that uses @code{gnu-build-system}
26608 (@pxref{Build Systems, @code{gnu-build-system}}).
26611 @unnumberedsec Building the Bootstrap Binaries
26613 @cindex bootstrap binaries
26614 Because the final tool chain does not depend on the bootstrap binaries,
26615 those rarely need to be updated. Nevertheless, it is useful to have an
26616 automated way to produce them, should an update occur, and this is what
26617 the @code{(gnu packages make-bootstrap)} module provides.
26619 The following command builds the tarballs containing the bootstrap
26620 binaries (Guile, Binutils, GCC, libc, and a tarball containing a mixture
26621 of Coreutils and other basic command-line tools):
26624 guix build bootstrap-tarballs
26627 The generated tarballs are those that should be referred to in the
26628 @code{(gnu packages bootstrap)} module mentioned at the beginning of
26631 Still here? Then perhaps by now you've started to wonder: when do we
26632 reach a fixed point? That is an interesting question! The answer is
26633 unknown, but if you would like to investigate further (and have
26634 significant computational and storage resources to do so), then let us
26637 @unnumberedsec Reducing the Set of Bootstrap Binaries
26639 Our bootstrap binaries currently include GCC, Guile, etc. That's a lot
26640 of binary code! Why is that a problem? It's a problem because these
26641 big chunks of binary code are practically non-auditable, which makes it
26642 hard to establish what source code produced them. Every unauditable
26643 binary also leaves us vulnerable to compiler backdoors as described by
26644 Ken Thompson in the 1984 paper @emph{Reflections on Trusting Trust}.
26646 This is mitigated by the fact that our bootstrap binaries were generated
26647 from an earlier Guix revision. Nevertheless it lacks the level of
26648 transparency that we get in the rest of the package dependency graph,
26649 where Guix always gives us a source-to-binary mapping. Thus, our goal
26650 is to reduce the set of bootstrap binaries to the bare minimum.
26652 The @uref{http://bootstrappable.org, Bootstrappable.org web site} lists
26653 on-going projects to do that. One of these is about replacing the
26654 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
26655 of increasing complexity, which could be built from source starting from
26656 a simple and auditable assembler. Your help is welcome!
26660 @chapter Porting to a New Platform
26662 As discussed above, the GNU distribution is self-contained, and
26663 self-containment is achieved by relying on pre-built ``bootstrap
26664 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
26665 operating system kernel, CPU architecture, and application binary
26666 interface (ABI). Thus, to port the distribution to a platform that is
26667 not yet supported, one must build those bootstrap binaries, and update
26668 the @code{(gnu packages bootstrap)} module to use them on that platform.
26670 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
26671 When everything goes well, and assuming the GNU tool chain supports the
26672 target platform, this can be as simple as running a command like this
26676 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
26679 For this to work, the @code{glibc-dynamic-linker} procedure in
26680 @code{(gnu packages bootstrap)} must be augmented to return the right
26681 file name for libc's dynamic linker on that platform; likewise,
26682 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
26683 taught about the new platform.
26685 Once these are built, the @code{(gnu packages bootstrap)} module needs
26686 to be updated to refer to these binaries on the target platform. That
26687 is, the hashes and URLs of the bootstrap tarballs for the new platform
26688 must be added alongside those of the currently supported platforms. The
26689 bootstrap Guile tarball is treated specially: it is expected to be
26690 available locally, and @file{gnu/local.mk} has rules to download it for
26691 the supported architectures; a rule for the new platform must be added
26694 In practice, there may be some complications. First, it may be that the
26695 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
26696 above) is not recognized by all the GNU tools. Typically, glibc
26697 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
26698 configure flag (see @code{gcc.scm} for examples of how to handle this).
26699 Second, some of the required packages could fail to build for that
26700 platform. Lastly, the generated binaries could be broken for some
26703 @c *********************************************************************
26704 @include contributing.texi
26706 @c *********************************************************************
26707 @node Acknowledgments
26708 @chapter Acknowledgments
26710 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
26711 which was designed and
26712 implemented by Eelco Dolstra, with contributions from other people (see
26713 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
26714 management, and promoted unprecedented features, such as transactional
26715 package upgrades and rollbacks, per-user profiles, and referentially
26716 transparent build processes. Without this work, Guix would not exist.
26718 The Nix-based software distributions, Nixpkgs and NixOS, have also been
26719 an inspiration for Guix.
26721 GNU@tie{}Guix itself is a collective work with contributions from a
26722 number of people. See the @file{AUTHORS} file in Guix for more
26723 information on these fine people. The @file{THANKS} file lists people
26724 who have helped by reporting bugs, taking care of the infrastructure,
26725 providing artwork and themes, making suggestions, and more---thank you!
26728 @c *********************************************************************
26729 @node GNU Free Documentation License
26730 @appendix GNU Free Documentation License
26731 @cindex license, GNU Free Documentation License
26732 @include fdl-1.3.texi
26734 @c *********************************************************************
26735 @node Concept Index
26736 @unnumbered Concept Index
26739 @node Programming Index
26740 @unnumbered Programming Index
26741 @syncodeindex tp fn
26742 @syncodeindex vr fn
26747 @c Local Variables:
26748 @c ispell-local-dictionary: "american";