6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
14 @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=15145
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER ci.guix.gnu.org
21 @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
24 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès@*
25 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
26 Copyright @copyright{} 2013 Nikita Karetnikov@*
27 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
28 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
29 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
30 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
31 Copyright @copyright{} 2015, 2016, 2017 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 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
562 -qO - | gpg --import -
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 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1909 -qO - | gpg --import -
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 @cindex subdirectory, channels
3925 @subsection Package Modules in a Sub-directory
3927 As a channel author, you may want to keep your channel modules in a
3928 sub-directory. If your modules are in the sub-directory @file{guix}, you must
3929 add a meta-data file @file{.guix-channel} that contains:
3937 @subsection Replicating Guix
3939 @cindex pinning, channels
3940 @cindex replicating Guix
3941 @cindex reproducibility, of Guix
3942 The @command{guix pull --list-generations} output above shows precisely which
3943 commits were used to build this instance of Guix. We can thus replicate it,
3944 say, on another machine, by providing a channel specification in
3945 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
3948 ;; Deploy specific commits of my channels of interest.
3951 (url "https://git.savannah.gnu.org/git/guix.git")
3952 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
3954 (name 'my-personal-packages)
3955 (url "https://example.org/personal-packages.git")
3956 (branch "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
3959 The @command{guix describe --format=channels} command can even generate this
3960 list of channels directly (@pxref{Invoking guix describe}).
3962 At this point the two machines run the @emph{exact same Guix}, with access to
3963 the @emph{exact same packages}. The output of @command{guix build gimp} on
3964 one machine will be exactly the same, bit for bit, as the output of the same
3965 command on the other machine. It also means both machines have access to all
3966 the source code of Guix and, transitively, to all the source code of every
3969 This gives you super powers, allowing you to track the provenance of binary
3970 artifacts with very fine grain, and to reproduce software environments at
3971 will---some sort of ``meta reproducibility'' capabilities, if you will.
3972 @xref{Inferiors}, for another way to take advantage of these super powers.
3977 @c TODO: Remove this once we're more confident about API stability.
3979 The functionality described here is a ``technology preview'' as of version
3980 @value{VERSION}. As such, the interface is subject to change.
3984 @cindex composition of Guix revisions
3985 Sometimes you might need to mix packages from the revision of Guix you're
3986 currently running with packages available in a different revision of Guix.
3987 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
3988 revisions in arbitrary ways.
3990 @cindex inferior packages
3991 Technically, an ``inferior'' is essentially a separate Guix process connected
3992 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
3993 @code{(guix inferior)} module allows you to create inferiors and to
3994 communicate with them. It also provides a high-level interface to browse and
3995 manipulate the packages that an inferior provides---@dfn{inferior packages}.
3997 When combined with channels (@pxref{Channels}), inferiors provide a simple way
3998 to interact with a separate revision of Guix. For example, let's assume you
3999 want to install in your profile the current @code{guile} package, along with
4000 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4001 because the newer @code{guile-json} has an incompatible API and you want to
4002 run your code against the old API@. To do that, you could write a manifest for
4003 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4004 manifest, you would create an inferior for that old Guix revision you care
4005 about, and you would look up the @code{guile-json} package in the inferior:
4008 (use-modules (guix inferior) (guix channels)
4009 (srfi srfi-1)) ;for 'first'
4012 ;; This is the old revision from which we want to
4013 ;; extract guile-json.
4016 (url "https://git.savannah.gnu.org/git/guix.git")
4018 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4021 ;; An inferior representing the above revision.
4022 (inferior-for-channels channels))
4024 ;; Now create a manifest with the current "guile" package
4025 ;; and the old "guile-json" package.
4027 (list (first (lookup-inferior-packages inferior "guile-json"))
4028 (specification->package "guile")))
4031 On its first run, @command{guix package --manifest} might have to build the
4032 channel you specified before it can create the inferior; subsequent runs will
4033 be much faster because the Guix revision will be cached.
4035 The @code{(guix inferior)} module provides the following procedures to open an
4038 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4039 [#:cache-directory] [#:ttl]
4040 Return an inferior for @var{channels}, a list of channels. Use the cache at
4041 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4042 This procedure opens a new connection to the build daemon.
4044 As a side effect, this procedure may build or substitute binaries for
4045 @var{channels}, which can take time.
4048 @deffn {Scheme Procedure} open-inferior @var{directory} @
4049 [#:command "bin/guix"]
4050 Open the inferior Guix in @var{directory}, running
4051 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4052 the inferior could not be launched.
4055 @cindex inferior packages
4056 The procedures listed below allow you to obtain and manipulate inferior
4059 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4060 Return the list of packages known to @var{inferior}.
4063 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4065 Return the sorted list of inferior packages matching @var{name} in
4066 @var{inferior}, with highest version numbers first. If @var{version} is true,
4067 return only packages with a version number prefixed by @var{version}.
4070 @deffn {Scheme Procedure} inferior-package? @var{obj}
4071 Return true if @var{obj} is an inferior package.
4074 @deffn {Scheme Procedure} inferior-package-name @var{package}
4075 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4076 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4077 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4078 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4079 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4080 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4081 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4082 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4083 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4084 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4085 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4086 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4087 These procedures are the counterpart of package record accessors
4088 (@pxref{package Reference}). Most of them work by querying the inferior
4089 @var{package} comes from, so the inferior must still be live when you call
4093 Inferior packages can be used transparently like any other package or
4094 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4095 transparently handled by the @code{packages->manifest} procedure, which is
4096 commonly use in manifests (@pxref{Invoking guix package, the
4097 @option{--manifest} option of @command{guix package}}). Thus you can insert
4098 an inferior package pretty much anywhere you would insert a regular package:
4099 in manifests, in the @code{packages} field of your @code{operating-system}
4100 declaration, and so on.
4102 @node Invoking guix describe
4103 @section Invoking @command{guix describe}
4105 @cindex reproducibility
4106 @cindex replicating Guix
4107 Often you may want to answer questions like: ``Which revision of Guix am I
4108 using?'' or ``Which channels am I using?'' This is useful information in many
4109 situations: if you want to @emph{replicate} an environment on a different
4110 machine or user account, if you want to report a bug or to determine what
4111 change in the channels you are using caused it, or if you want to record your
4112 system state for reproducibility purposes. The @command{guix describe}
4113 command answers these questions.
4115 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4116 displays the channel(s) that it was built from, including their repository URL
4117 and commit IDs (@pxref{Channels}):
4121 Generation 10 Sep 03 2018 17:32:44 (current)
4123 repository URL: https://git.savannah.gnu.org/git/guix.git
4125 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4128 If you're familiar with the Git version control system, this is similar in
4129 spirit to @command{git describe}; the output is also similar to that of
4130 @command{guix pull --list-generations}, but limited to the current generation
4131 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4132 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4133 information is all it takes to describe the revision of Guix you're using, and
4134 also to replicate it.
4136 To make it easier to replicate Guix, @command{guix describe} can also be asked
4137 to return a list of channels instead of the human-readable description above:
4140 $ guix describe -f channels
4143 (url "https://git.savannah.gnu.org/git/guix.git")
4145 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4149 You can save this to a file and feed it to @command{guix pull -C} on some
4150 other machine or at a later point in time, which will instantiate @emph{this
4151 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4152 From there on, since you're able to deploy the same revision of Guix, you can
4153 just as well @emph{replicate a complete software environment}. We humbly
4154 think that this is @emph{awesome}, and we hope you'll like it too!
4156 The details of the options supported by @command{guix describe} are as
4160 @item --format=@var{format}
4161 @itemx -f @var{format}
4162 Produce output in the specified @var{format}, one of:
4166 produce human-readable output;
4168 produce a list of channel specifications that can be passed to @command{guix
4169 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4173 produce a list of channel specifications in JSON format;
4175 produce a list of channel specifications in Recutils format.
4178 @item --profile=@var{profile}
4179 @itemx -p @var{profile}
4180 Display information about @var{profile}.
4183 @node Invoking guix archive
4184 @section Invoking @command{guix archive}
4186 @cindex @command{guix archive}
4188 The @command{guix archive} command allows users to @dfn{export} files
4189 from the store into a single archive, and to later @dfn{import} them on
4190 a machine that runs Guix.
4191 In particular, it allows store files to be transferred from one machine
4192 to the store on another machine.
4195 If you're looking for a way to produce archives in a format suitable for
4196 tools other than Guix, @pxref{Invoking guix pack}.
4199 @cindex exporting store items
4200 To export store files as an archive to standard output, run:
4203 guix archive --export @var{options} @var{specifications}...
4206 @var{specifications} may be either store file names or package
4207 specifications, as for @command{guix package} (@pxref{Invoking guix
4208 package}). For instance, the following command creates an archive
4209 containing the @code{gui} output of the @code{git} package and the main
4210 output of @code{emacs}:
4213 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4216 If the specified packages are not built yet, @command{guix archive}
4217 automatically builds them. The build process may be controlled with the
4218 common build options (@pxref{Common Build Options}).
4220 To transfer the @code{emacs} package to a machine connected over SSH,
4224 guix archive --export -r emacs | ssh the-machine guix archive --import
4228 Similarly, a complete user profile may be transferred from one machine
4229 to another like this:
4232 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4233 ssh the-machine guix archive --import
4237 However, note that, in both examples, all of @code{emacs} and the
4238 profile as well as all of their dependencies are transferred (due to
4239 @code{-r}), regardless of what is already available in the store on the
4240 target machine. The @code{--missing} option can help figure out which
4241 items are missing from the target store. The @command{guix copy}
4242 command simplifies and optimizes this whole process, so this is probably
4243 what you should use in this case (@pxref{Invoking guix copy}).
4245 @cindex nar, archive format
4246 @cindex normalized archive (nar)
4247 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4248 comparable in spirit to `tar', but with differences
4249 that make it more appropriate for our purposes. First, rather than
4250 recording all Unix metadata for each file, the nar format only mentions
4251 the file type (regular, directory, or symbolic link); Unix permissions
4252 and owner/group are dismissed. Second, the order in which directory
4253 entries are stored always follows the order of file names according to
4254 the C locale collation order. This makes archive production fully
4257 When exporting, the daemon digitally signs the contents of the archive,
4258 and that digital signature is appended. When importing, the daemon
4259 verifies the signature and rejects the import in case of an invalid
4260 signature or if the signing key is not authorized.
4261 @c FIXME: Add xref to daemon doc about signatures.
4263 The main options are:
4267 Export the specified store files or packages (see below.) Write the
4268 resulting archive to the standard output.
4270 Dependencies are @emph{not} included in the output, unless
4271 @code{--recursive} is passed.
4275 When combined with @code{--export}, this instructs @command{guix
4276 archive} to include dependencies of the given items in the archive.
4277 Thus, the resulting archive is self-contained: it contains the closure
4278 of the exported store items.
4281 Read an archive from the standard input, and import the files listed
4282 therein into the store. Abort if the archive has an invalid digital
4283 signature, or if it is signed by a public key not among the authorized
4284 keys (see @code{--authorize} below.)
4287 Read a list of store file names from the standard input, one per line,
4288 and write on the standard output the subset of these files missing from
4291 @item --generate-key[=@var{parameters}]
4292 @cindex signing, archives
4293 Generate a new key pair for the daemon. This is a prerequisite before
4294 archives can be exported with @code{--export}. Note that this operation
4295 usually takes time, because it needs to gather enough entropy to
4296 generate the key pair.
4298 The generated key pair is typically stored under @file{/etc/guix}, in
4299 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4300 key, which must be kept secret.) When @var{parameters} is omitted,
4301 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4302 versions before 1.6.0, it is a 4096-bit RSA key.
4303 Alternatively, @var{parameters} can specify
4304 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4305 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4306 Libgcrypt Reference Manual}).
4309 @cindex authorizing, archives
4310 Authorize imports signed by the public key passed on standard input.
4311 The public key must be in ``s-expression advanced format''---i.e., the
4312 same format as the @file{signing-key.pub} file.
4314 The list of authorized keys is kept in the human-editable file
4315 @file{/etc/guix/acl}. The file contains
4316 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4317 s-expressions''} and is structured as an access-control list in the
4318 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4321 @item --extract=@var{directory}
4322 @itemx -x @var{directory}
4323 Read a single-item archive as served by substitute servers
4324 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4325 low-level operation needed in only very narrow use cases; see below.
4327 For example, the following command extracts the substitute for Emacs
4328 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4332 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-emacs-24.5 \
4333 | bunzip2 | guix archive -x /tmp/emacs
4336 Single-item archives are different from multiple-item archives produced
4337 by @command{guix archive --export}; they contain a single store item,
4338 and they do @emph{not} embed a signature. Thus this operation does
4339 @emph{no} signature verification and its output should be considered
4342 The primary purpose of this operation is to facilitate inspection of
4343 archive contents coming from possibly untrusted substitute servers.
4348 @c *********************************************************************
4350 @chapter Development
4352 @cindex software development
4353 If you are a software developer, Guix provides tools that you should find
4354 helpful---independently of the language you're developing in. This is what
4355 this chapter is about.
4357 The @command{guix environment} command provides a convenient way to set up
4358 @dfn{development environments} containing all the dependencies and tools
4359 necessary to work on the software package of your choice. The @command{guix
4360 pack} command allows you to create @dfn{application bundles} that can be
4361 easily distributed to users who do not run Guix.
4364 * Invoking guix environment:: Setting up development environments.
4365 * Invoking guix pack:: Creating software bundles.
4368 @node Invoking guix environment
4369 @section Invoking @command{guix environment}
4371 @cindex reproducible build environments
4372 @cindex development environments
4373 @cindex @command{guix environment}
4374 @cindex environment, package build environment
4375 The purpose of @command{guix environment} is to assist hackers in
4376 creating reproducible development environments without polluting their
4377 package profile. The @command{guix environment} tool takes one or more
4378 packages, builds all of their inputs, and creates a shell
4379 environment to use them.
4381 The general syntax is:
4384 guix environment @var{options} @var{package}@dots{}
4387 The following example spawns a new shell set up for the development of
4391 guix environment guile
4394 If the needed dependencies are not built yet, @command{guix environment}
4395 automatically builds them. The environment of the new shell is an augmented
4396 version of the environment that @command{guix environment} was run in.
4397 It contains the necessary search paths for building the given package
4398 added to the existing environment variables. To create a ``pure''
4399 environment, in which the original environment variables have been unset,
4400 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4401 environment variables such as @code{PATH} in their @file{~/.bashrc}
4402 file. As a consequence, when @code{guix environment} launches it, Bash
4403 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4404 environment variables. It is an error to define such environment
4405 variables in @file{.bashrc}; instead, they should be defined in
4406 @file{.bash_profile}, which is sourced only by log-in shells.
4407 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4408 details on Bash start-up files.}.
4410 @vindex GUIX_ENVIRONMENT
4411 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4412 variable in the shell it spawns; its value is the file name of the
4413 profile of this environment. This allows users to, say, define a
4414 specific prompt for development environments in their @file{.bashrc}
4415 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4418 if [ -n "$GUIX_ENVIRONMENT" ]
4420 export PS1="\u@@\h \w [dev]\$ "
4425 ...@: or to browse the profile:
4428 $ ls "$GUIX_ENVIRONMENT/bin"
4431 Additionally, more than one package may be specified, in which case the
4432 union of the inputs for the given packages are used. For example, the
4433 command below spawns a shell where all of the dependencies of both Guile
4434 and Emacs are available:
4437 guix environment guile emacs
4440 Sometimes an interactive shell session is not desired. An arbitrary
4441 command may be invoked by placing the @code{--} token to separate the
4442 command from the rest of the arguments:
4445 guix environment guile -- make -j4
4448 In other situations, it is more convenient to specify the list of
4449 packages needed in the environment. For example, the following command
4450 runs @command{python} from an environment containing Python@tie{}2.7 and
4454 guix environment --ad-hoc python2-numpy python-2.7 -- python
4457 Furthermore, one might want the dependencies of a package and also some
4458 additional packages that are not build-time or runtime dependencies, but
4459 are useful when developing nonetheless. Because of this, the
4460 @code{--ad-hoc} flag is positional. Packages appearing before
4461 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4462 added to the environment. Packages appearing after are interpreted as
4463 packages that will be added to the environment directly. For example,
4464 the following command creates a Guix development environment that
4465 additionally includes Git and strace:
4468 guix environment guix --ad-hoc git strace
4471 Sometimes it is desirable to isolate the environment as much as
4472 possible, for maximal purity and reproducibility. In particular, when
4473 using Guix on a host distro that is not Guix System, it is desirable to
4474 prevent access to @file{/usr/bin} and other system-wide resources from
4475 the development environment. For example, the following command spawns
4476 a Guile REPL in a ``container'' where only the store and the current
4477 working directory are mounted:
4480 guix environment --ad-hoc --container guile -- guile
4484 The @code{--container} option requires Linux-libre 3.19 or newer.
4487 The available options are summarized below.
4490 @item --root=@var{file}
4491 @itemx -r @var{file}
4492 @cindex persistent environment
4493 @cindex garbage collector root, for environments
4494 Make @var{file} a symlink to the profile for this environment, and
4495 register it as a garbage collector root.
4497 This is useful if you want to protect your environment from garbage
4498 collection, to make it ``persistent''.
4500 When this option is omitted, the environment is protected from garbage
4501 collection only for the duration of the @command{guix environment}
4502 session. This means that next time you recreate the same environment,
4503 you could have to rebuild or re-download packages. @xref{Invoking guix
4504 gc}, for more on GC roots.
4506 @item --expression=@var{expr}
4507 @itemx -e @var{expr}
4508 Create an environment for the package or list of packages that
4509 @var{expr} evaluates to.
4511 For example, running:
4514 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4517 starts a shell with the environment for this specific variant of the
4523 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4526 starts a shell with all the base system packages available.
4528 The above commands only use the default output of the given packages.
4529 To select other outputs, two element tuples can be specified:
4532 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4535 @item --load=@var{file}
4536 @itemx -l @var{file}
4537 Create an environment for the package or list of packages that the code
4538 within @var{file} evaluates to.
4540 As an example, @var{file} might contain a definition like this
4541 (@pxref{Defining Packages}):
4544 @verbatiminclude environment-gdb.scm
4547 @item --manifest=@var{file}
4548 @itemx -m @var{file}
4549 Create an environment for the packages contained in the manifest object
4550 returned by the Scheme code in @var{file}.
4552 This is similar to the same-named option in @command{guix package}
4553 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4557 Include all specified packages in the resulting environment, as if an
4558 @i{ad hoc} package were defined with them as inputs. This option is
4559 useful for quickly creating an environment without having to write a
4560 package expression to contain the desired inputs.
4562 For instance, the command:
4565 guix environment --ad-hoc guile guile-sdl -- guile
4568 runs @command{guile} in an environment where Guile and Guile-SDL are
4571 Note that this example implicitly asks for the default output of
4572 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4573 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4574 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4576 This option may be composed with the default behavior of @command{guix
4577 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4578 as packages whose dependencies will be added to the environment, the
4579 default behavior. Packages appearing after are interpreted as packages
4580 that will be added to the environment directly.
4583 Unset existing environment variables when building the new environment, except
4584 those specified with @option{--preserve} (see below.) This has the effect of
4585 creating an environment in which search paths only contain package inputs.
4587 @item --preserve=@var{regexp}
4588 @itemx -E @var{regexp}
4589 When used alongside @option{--pure}, preserve the environment variables
4590 matching @var{regexp}---in other words, put them on a ``white list'' of
4591 environment variables that must be preserved. This option can be repeated
4595 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4599 This example runs @command{mpirun} in a context where the only environment
4600 variables defined are @code{PATH}, environment variables whose name starts
4601 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4604 @item --search-paths
4605 Display the environment variable definitions that make up the
4608 @item --system=@var{system}
4609 @itemx -s @var{system}
4610 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4615 Run @var{command} within an isolated container. The current working
4616 directory outside the container is mapped inside the container.
4617 Additionally, unless overridden with @code{--user}, a dummy home
4618 directory is created that matches the current user's home directory, and
4619 @file{/etc/passwd} is configured accordingly.
4621 The spawned process runs as the current user outside the container. Inside
4622 the container, it has the same UID and GID as the current user, unless
4623 @option{--user} is passed (see below.)
4627 For containers, share the network namespace with the host system.
4628 Containers created without this flag only have access to the loopback
4631 @item --link-profile
4633 For containers, link the environment profile to
4634 @file{~/.guix-profile} within the container. This is equivalent to
4635 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4636 within the container. Linking will fail and abort the environment if
4637 the directory already exists, which will certainly be the case if
4638 @command{guix environment} was invoked in the user's home directory.
4640 Certain packages are configured to look in
4641 @code{~/.guix-profile} for configuration files and data;@footnote{For
4642 example, the @code{fontconfig} package inspects
4643 @file{~/.guix-profile/share/fonts} for additional fonts.}
4644 @code{--link-profile} allows these programs to behave as expected within
4647 @item --user=@var{user}
4648 @itemx -u @var{user}
4649 For containers, use the username @var{user} in place of the current
4650 user. The generated @file{/etc/passwd} entry within the container will
4651 contain the name @var{user}, the home directory will be
4652 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4653 the UID and GID inside the container are 1000. @var{user}
4654 need not exist on the system.
4656 Additionally, any shared or exposed path (see @code{--share} and
4657 @code{--expose} respectively) whose target is within the current user's
4658 home directory will be remapped relative to @file{/home/USER}; this
4659 includes the automatic mapping of the current working directory.
4662 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4664 guix environment --container --user=foo \
4665 --expose=$HOME/test \
4666 --expose=/tmp/target=$HOME/target
4669 While this will limit the leaking of user identity through home paths
4670 and each of the user fields, this is only one useful component of a
4671 broader privacy/anonymity solution---not one in and of itself.
4674 For containers, the default behavior is to share the current working
4675 directory with the isolated container and immediately change to that
4676 directory within the container. If this is undesirable, @code{--no-cwd}
4677 will cause the current working directory to @emph{not} be automatically
4678 shared and will change to the user's home directory within the container
4679 instead. See also @code{--user}.
4681 @item --expose=@var{source}[=@var{target}]
4682 For containers, expose the file system @var{source} from the host system
4683 as the read-only file system @var{target} within the container. If
4684 @var{target} is not specified, @var{source} is used as the target mount
4685 point in the container.
4687 The example below spawns a Guile REPL in a container in which the user's
4688 home directory is accessible read-only via the @file{/exchange}
4692 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
4695 @item --share=@var{source}[=@var{target}]
4696 For containers, share the file system @var{source} from the host system
4697 as the writable file system @var{target} within the container. If
4698 @var{target} is not specified, @var{source} is used as the target mount
4699 point in the container.
4701 The example below spawns a Guile REPL in a container in which the user's
4702 home directory is accessible for both reading and writing via the
4703 @file{/exchange} directory:
4706 guix environment --container --share=$HOME=/exchange --ad-hoc guile -- guile
4710 @command{guix environment}
4711 also supports all of the common build options that @command{guix
4712 build} supports (@pxref{Common Build Options}) as well as package
4713 transformation options (@pxref{Package Transformation Options}).
4715 @node Invoking guix pack
4716 @section Invoking @command{guix pack}
4718 Occasionally you want to pass software to people who are not (yet!)
4719 lucky enough to be using Guix. You'd tell them to run @command{guix
4720 package -i @var{something}}, but that's not possible in this case. This
4721 is where @command{guix pack} comes in.
4724 If you are looking for ways to exchange binaries among machines that
4725 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
4726 publish}, and @ref{Invoking guix archive}.
4731 @cindex application bundle
4732 @cindex software bundle
4733 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
4734 @dfn{software bundle}: it creates a tarball or some other archive
4735 containing the binaries of the software you're interested in, and all
4736 its dependencies. The resulting archive can be used on any machine that
4737 does not have Guix, and people can run the exact same binaries as those
4738 you have with Guix. The pack itself is created in a bit-reproducible
4739 fashion, so anyone can verify that it really contains the build results
4740 that you pretend to be shipping.
4742 For example, to create a bundle containing Guile, Emacs, Geiser, and all
4743 their dependencies, you can run:
4746 $ guix pack guile emacs geiser
4748 /gnu/store/@dots{}-pack.tar.gz
4751 The result here is a tarball containing a @file{/gnu/store} directory
4752 with all the relevant packages. The resulting tarball contains a
4753 @dfn{profile} with the three packages of interest; the profile is the
4754 same as would be created by @command{guix package -i}. It is this
4755 mechanism that is used to create Guix's own standalone binary tarball
4756 (@pxref{Binary Installation}).
4758 Users of this pack would have to run
4759 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
4760 find inconvenient. To work around it, you can create, say, a
4761 @file{/opt/gnu/bin} symlink to the profile:
4764 guix pack -S /opt/gnu/bin=bin guile emacs geiser
4768 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
4770 @cindex relocatable binaries, with @command{guix pack}
4771 What if the recipient of your pack does not have root privileges on
4772 their machine, and thus cannot unpack it in the root file system? In
4773 that case, you will want to use the @code{--relocatable} option (see
4774 below). This option produces @dfn{relocatable binaries}, meaning they
4775 they can be placed anywhere in the file system hierarchy: in the example
4776 above, users can unpack your tarball in their home directory and
4777 directly run @file{./opt/gnu/bin/guile}.
4779 @cindex Docker, build an image with guix pack
4780 Alternatively, you can produce a pack in the Docker image format using
4781 the following command:
4784 guix pack -f docker guile emacs geiser
4788 The result is a tarball that can be passed to the @command{docker load}
4790 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
4791 documentation} for more information.
4793 @cindex Singularity, build an image with guix pack
4794 @cindex SquashFS, build an image with guix pack
4795 Yet another option is to produce a SquashFS image with the following
4799 guix pack -f squashfs guile emacs geiser
4803 The result is a SquashFS file system image that can either be mounted or
4804 directly be used as a file system container image with the
4805 @uref{https://singularity.lbl.gov, Singularity container execution
4806 environment}, using commands like @command{singularity shell} or
4807 @command{singularity exec}.
4809 Several command-line options allow you to customize your pack:
4812 @item --format=@var{format}
4813 @itemx -f @var{format}
4814 Produce a pack in the given @var{format}.
4816 The available formats are:
4820 This is the default format. It produces a tarball containing all the
4821 specified binaries and symlinks.
4824 This produces a tarball that follows the
4825 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
4826 Docker Image Specification}.
4829 This produces a SquashFS image containing all the specified binaries and
4830 symlinks, as well as empty mount points for virtual file systems like
4834 @cindex relocatable binaries
4837 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
4838 anywhere in the file system hierarchy and run from there.
4840 When this option is passed once, the resulting binaries require support for
4841 @dfn{user namespaces} in the kernel Linux; when passed
4842 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
4843 PRoot support, can be thought of as the abbreviation of ``Really
4844 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
4845 if user namespaces are unavailable, and essentially work anywhere---see below
4846 for the implications.
4848 For example, if you create a pack containing Bash with:
4851 guix pack -RR -S /mybin=bin bash
4855 ...@: you can copy that pack to a machine that lacks Guix, and from your
4856 home directory as a normal user, run:
4864 In that shell, if you type @code{ls /gnu/store}, you'll notice that
4865 @file{/gnu/store} shows up and contains all the dependencies of
4866 @code{bash}, even though the machine actually lacks @file{/gnu/store}
4867 altogether! That is probably the simplest way to deploy Guix-built
4868 software on a non-Guix machine.
4871 By default, relocatable binaries rely on the @dfn{user namespace} feature of
4872 the kernel Linux, which allows unprivileged users to mount or change root.
4873 Old versions of Linux did not support it, and some GNU/Linux distributions
4876 To produce relocatable binaries that work even in the absence of user
4877 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
4878 case, binaries will try user namespace support and fall back to PRoot if user
4879 namespaces are not supported.
4881 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
4882 support for file system virtualization. It achieves that by using the
4883 @code{ptrace} system call on the running program. This approach has the
4884 advantage to work without requiring special kernel support, but it incurs
4885 run-time overhead every time a system call is made.
4888 @cindex entry point, for Docker images
4889 @item --entry-point=@var{command}
4890 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
4891 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
4892 support it. @var{command} must be relative to the profile contained in the
4895 The entry point specifies the command that tools like @code{docker run} or
4896 @code{singularity run} automatically start by default. For example, you can
4900 guix pack -f docker --entry-point=bin/guile guile
4903 The resulting pack can easily be loaded and @code{docker run} with no extra
4904 arguments will spawn @code{bin/guile}:
4907 docker load -i pack.tar.gz
4908 docker run @var{image-id}
4911 @item --expression=@var{expr}
4912 @itemx -e @var{expr}
4913 Consider the package @var{expr} evaluates to.
4915 This has the same purpose as the same-named option in @command{guix
4916 build} (@pxref{Additional Build Options, @code{--expression} in
4917 @command{guix build}}).
4919 @item --manifest=@var{file}
4920 @itemx -m @var{file}
4921 Use the packages contained in the manifest object returned by the Scheme
4924 This has a similar purpose as the same-named option in @command{guix
4925 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
4926 same manifest files. It allows you to define a collection of packages
4927 once and use it both for creating profiles and for creating archives
4928 for use on machines that do not have Guix installed. Note that you can
4929 specify @emph{either} a manifest file @emph{or} a list of packages,
4932 @item --system=@var{system}
4933 @itemx -s @var{system}
4934 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4935 the system type of the build host.
4937 @item --target=@var{triplet}
4938 @cindex cross-compilation
4939 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
4940 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
4941 configuration triplets,, autoconf, Autoconf}).
4943 @item --compression=@var{tool}
4944 @itemx -C @var{tool}
4945 Compress the resulting tarball using @var{tool}---one of @code{gzip},
4946 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
4948 @item --symlink=@var{spec}
4949 @itemx -S @var{spec}
4950 Add the symlinks specified by @var{spec} to the pack. This option can
4951 appear several times.
4953 @var{spec} has the form @code{@var{source}=@var{target}}, where
4954 @var{source} is the symlink that will be created and @var{target} is the
4957 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
4958 symlink pointing to the @file{bin} sub-directory of the profile.
4960 @item --save-provenance
4961 Save provenance information for the packages passed on the command line.
4962 Provenance information includes the URL and commit of the channels in use
4965 Provenance information is saved in the
4966 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
4967 usual package metadata---the name and version of each package, their
4968 propagated inputs, and so on. It is useful information to the recipient of
4969 the pack, who then knows how the pack was (supposedly) obtained.
4971 This option is not enabled by default because, like timestamps, provenance
4972 information contributes nothing to the build process. In other words, there
4973 is an infinity of channel URLs and commit IDs that can lead to the same pack.
4974 Recording such ``silent'' metadata in the output thus potentially breaks the
4975 source-to-binary bitwise reproducibility property.
4977 @item --root=@var{file}
4978 @itemx -r @var{file}
4979 @cindex garbage collector root, for packs
4980 Make @var{file} a symlink to the resulting pack, and register it as a garbage
4983 @item --localstatedir
4984 @itemx --profile-name=@var{name}
4985 Include the ``local state directory'', @file{/var/guix}, in the resulting
4986 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
4987 profile---by default @var{name} is @code{guix-profile}, which corresponds to
4988 @file{~root/.guix-profile}.
4990 @file{/var/guix} contains the store database (@pxref{The Store}) as well
4991 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
4992 the pack means that the store is ``complete'' and manageable by Guix;
4993 not providing it pack means that the store is ``dead'': items cannot be
4994 added to it or removed from it after extraction of the pack.
4996 One use case for this is the Guix self-contained binary tarball
4997 (@pxref{Binary Installation}).
5000 Use the bootstrap binaries to build the pack. This option is only
5001 useful to Guix developers.
5004 In addition, @command{guix pack} supports all the common build options
5005 (@pxref{Common Build Options}) and all the package transformation
5006 options (@pxref{Package Transformation Options}).
5009 @c *********************************************************************
5010 @node Programming Interface
5011 @chapter Programming Interface
5013 GNU Guix provides several Scheme programming interfaces (APIs) to
5014 define, build, and query packages. The first interface allows users to
5015 write high-level package definitions. These definitions refer to
5016 familiar packaging concepts, such as the name and version of a package,
5017 its build system, and its dependencies. These definitions can then be
5018 turned into concrete build actions.
5020 Build actions are performed by the Guix daemon, on behalf of users. In a
5021 standard setup, the daemon has write access to the store---the
5022 @file{/gnu/store} directory---whereas users do not. The recommended
5023 setup also has the daemon perform builds in chroots, under a specific
5024 build users, to minimize interference with the rest of the system.
5027 Lower-level APIs are available to interact with the daemon and the
5028 store. To instruct the daemon to perform a build action, users actually
5029 provide it with a @dfn{derivation}. A derivation is a low-level
5030 representation of the build actions to be taken, and the environment in
5031 which they should occur---derivations are to package definitions what
5032 assembly is to C programs. The term ``derivation'' comes from the fact
5033 that build results @emph{derive} from them.
5035 This chapter describes all these APIs in turn, starting from high-level
5036 package definitions.
5039 * Package Modules:: Packages from the programmer's viewpoint.
5040 * Defining Packages:: Defining new packages.
5041 * Build Systems:: Specifying how packages are built.
5042 * The Store:: Manipulating the package store.
5043 * Derivations:: Low-level interface to package derivations.
5044 * The Store Monad:: Purely functional interface to the store.
5045 * G-Expressions:: Manipulating build expressions.
5046 * Invoking guix repl:: Fiddling with Guix interactively.
5049 @node Package Modules
5050 @section Package Modules
5052 From a programming viewpoint, the package definitions of the
5053 GNU distribution are provided by Guile modules in the @code{(gnu packages
5054 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5055 packages @dots{})} module name space are not necessarily ``GNU
5056 packages''. This module naming scheme follows the usual Guile module
5057 naming convention: @code{gnu} means that these modules are distributed
5058 as part of the GNU system, and @code{packages} identifies modules that
5059 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5060 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5061 module exports a variable named @code{emacs}, which is bound to a
5062 @code{<package>} object (@pxref{Defining Packages}).
5064 The @code{(gnu packages @dots{})} module name space is
5065 automatically scanned for packages by the command-line tools. For
5066 instance, when running @code{guix install emacs}, all the @code{(gnu
5067 packages @dots{})} modules are scanned until one that exports a package
5068 object whose name is @code{emacs} is found. This package search
5069 facility is implemented in the @code{(gnu packages)} module.
5071 @cindex customization, of packages
5072 @cindex package module search path
5073 Users can store package definitions in modules with different
5074 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5075 name and module name must match. For instance, the @code{(my-packages
5076 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5077 relative to the load path specified with @option{--load-path} or
5078 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5079 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5080 these package definitions visible to the user interfaces:
5084 By adding the directory containing your package modules to the search path
5085 with the @code{-L} flag of @command{guix package} and other commands
5086 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5087 environment variable described below.
5090 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5091 pulls from it. A channel is essentially a Git repository containing package
5092 modules. @xref{Channels}, for more information on how to define and use
5096 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5098 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5099 This is a colon-separated list of directories to search for additional
5100 package modules. Directories listed in this variable take precedence
5101 over the own modules of the distribution.
5104 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5105 each package is built based solely on other packages in the
5106 distribution. The root of this dependency graph is a small set of
5107 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5108 bootstrap)} module. For more information on bootstrapping,
5109 @pxref{Bootstrapping}.
5111 @node Defining Packages
5112 @section Defining Packages
5114 The high-level interface to package definitions is implemented in the
5115 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5116 example, the package definition, or @dfn{recipe}, for the GNU Hello
5117 package looks like this:
5120 (define-module (gnu packages hello)
5121 #:use-module (guix packages)
5122 #:use-module (guix download)
5123 #:use-module (guix build-system gnu)
5124 #:use-module (guix licenses)
5125 #:use-module (gnu packages gawk))
5127 (define-public hello
5133 (uri (string-append "mirror://gnu/hello/hello-" version
5137 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5138 (build-system gnu-build-system)
5139 (arguments '(#:configure-flags '("--enable-silent-rules")))
5140 (inputs `(("gawk" ,gawk)))
5141 (synopsis "Hello, GNU world: An example GNU package")
5142 (description "Guess what GNU Hello prints!")
5143 (home-page "https://www.gnu.org/software/hello/")
5148 Without being a Scheme expert, the reader may have guessed the meaning
5149 of the various fields here. This expression binds the variable
5150 @code{hello} to a @code{<package>} object, which is essentially a record
5151 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5152 This package object can be inspected using procedures found in the
5153 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5154 returns---surprise!---@code{"hello"}.
5156 With luck, you may be able to import part or all of the definition of
5157 the package you are interested in from another repository, using the
5158 @code{guix import} command (@pxref{Invoking guix import}).
5160 In the example above, @var{hello} is defined in a module of its own,
5161 @code{(gnu packages hello)}. Technically, this is not strictly
5162 necessary, but it is convenient to do so: all the packages defined in
5163 modules under @code{(gnu packages @dots{})} are automatically known to
5164 the command-line tools (@pxref{Package Modules}).
5166 There are a few points worth noting in the above package definition:
5170 The @code{source} field of the package is an @code{<origin>} object
5171 (@pxref{origin Reference}, for the complete reference).
5172 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5173 meaning that the source is a file to be downloaded over FTP or HTTP.
5175 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5176 the GNU mirrors defined in @code{(guix download)}.
5178 The @code{sha256} field specifies the expected SHA256 hash of the file
5179 being downloaded. It is mandatory, and allows Guix to check the
5180 integrity of the file. The @code{(base32 @dots{})} form introduces the
5181 base32 representation of the hash. You can obtain this information with
5182 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5183 hash} (@pxref{Invoking guix hash}).
5186 When needed, the @code{origin} form can also have a @code{patches} field
5187 listing patches to be applied, and a @code{snippet} field giving a
5188 Scheme expression to modify the source code.
5191 @cindex GNU Build System
5192 The @code{build-system} field specifies the procedure to build the
5193 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5194 represents the familiar GNU Build System, where packages may be
5195 configured, built, and installed with the usual @code{./configure &&
5196 make && make check && make install} command sequence.
5199 The @code{arguments} field specifies options for the build system
5200 (@pxref{Build Systems}). Here it is interpreted by
5201 @var{gnu-build-system} as a request run @file{configure} with the
5202 @code{--enable-silent-rules} flag.
5208 What about these quote (@code{'}) characters? They are Scheme syntax to
5209 introduce a literal list; @code{'} is synonymous with @code{quote}.
5210 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5211 for details. Here the value of the @code{arguments} field is a list of
5212 arguments passed to the build system down the road, as with @code{apply}
5213 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5216 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5217 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5218 @code{#:configure-flags} is a keyword used to pass a keyword argument
5219 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5223 The @code{inputs} field specifies inputs to the build process---i.e.,
5224 build-time or run-time dependencies of the package. Here, we define an
5225 input called @code{"gawk"} whose value is that of the @var{gawk}
5226 variable; @var{gawk} is itself bound to a @code{<package>} object.
5228 @cindex backquote (quasiquote)
5231 @cindex comma (unquote)
5235 @findex unquote-splicing
5236 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5237 us to introduce a literal list in the @code{inputs} field, while
5238 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5239 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5242 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5243 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5244 of ensuring that they are present (@pxref{Build Systems}).
5246 However, any other dependencies need to be specified in the
5247 @code{inputs} field. Any dependency not specified here will simply be
5248 unavailable to the build process, possibly leading to a build failure.
5251 @xref{package Reference}, for a full description of possible fields.
5253 Once a package definition is in place, the
5254 package may actually be built using the @code{guix build} command-line
5255 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5256 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5257 package definition using the @command{guix edit} command
5258 (@pxref{Invoking guix edit}).
5259 @xref{Packaging Guidelines}, for
5260 more information on how to test package definitions, and
5261 @ref{Invoking guix lint}, for information on how to check a definition
5262 for style conformance.
5263 @vindex GUIX_PACKAGE_PATH
5264 Lastly, @pxref{Channels}, for information
5265 on how to extend the distribution by adding your own package definitions
5268 Finally, updating the package definition to a new upstream version
5269 can be partly automated by the @command{guix refresh} command
5270 (@pxref{Invoking guix refresh}).
5272 Behind the scenes, a derivation corresponding to the @code{<package>}
5273 object is first computed by the @code{package-derivation} procedure.
5274 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5275 The build actions it prescribes may then be realized by using the
5276 @code{build-derivations} procedure (@pxref{The Store}).
5278 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5279 Return the @code{<derivation>} object of @var{package} for @var{system}
5280 (@pxref{Derivations}).
5282 @var{package} must be a valid @code{<package>} object, and @var{system}
5283 must be a string denoting the target system type---e.g.,
5284 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5285 must be a connection to the daemon, which operates on the store
5286 (@pxref{The Store}).
5290 @cindex cross-compilation
5291 Similarly, it is possible to compute a derivation that cross-builds a
5292 package for some other system:
5294 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5295 @var{package} @var{target} [@var{system}]
5296 Return the @code{<derivation>} object of @var{package} cross-built from
5297 @var{system} to @var{target}.
5299 @var{target} must be a valid GNU triplet denoting the target hardware
5300 and operating system, such as @code{"mips64el-linux-gnu"}
5301 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5304 @cindex package transformations
5305 @cindex input rewriting
5306 @cindex dependency tree rewriting
5307 Packages can be manipulated in arbitrary ways. An example of a useful
5308 transformation is @dfn{input rewriting}, whereby the dependency tree of
5309 a package is rewritten by replacing specific inputs by others:
5311 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5312 [@var{rewrite-name}]
5313 Return a procedure that, when passed a package, replaces its direct and
5314 indirect dependencies (but not its implicit inputs) according to
5315 @var{replacements}. @var{replacements} is a list of package pairs; the
5316 first element of each pair is the package to replace, and the second one
5319 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5320 the name of a package and returns its new name after rewrite.
5324 Consider this example:
5327 (define libressl-instead-of-openssl
5328 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5330 (package-input-rewriting `((,openssl . ,libressl))))
5332 (define git-with-libressl
5333 (libressl-instead-of-openssl git))
5337 Here we first define a rewriting procedure that replaces @var{openssl}
5338 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5339 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5340 This is exactly what the @option{--with-input} command-line option does
5341 (@pxref{Package Transformation Options, @option{--with-input}}).
5343 The following variant of @code{package-input-rewriting} can match packages to
5344 be replaced by name rather than by identity.
5346 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5347 Return a procedure that, given a package, applies the given @var{replacements} to
5348 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5349 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5350 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5351 replacement for that package.
5354 The example above could be rewritten this way:
5357 (define libressl-instead-of-openssl
5358 ;; Replace all the packages called "openssl" with LibreSSL.
5359 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5362 The key difference here is that, this time, packages are matched by spec and
5363 not by identity. In other words, any package in the graph that is called
5364 @code{openssl} will be replaced.
5366 A more generic procedure to rewrite a package dependency graph is
5367 @code{package-mapping}: it supports arbitrary changes to nodes in the
5370 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5371 Return a procedure that, given a package, applies @var{proc} to all the packages
5372 depended on and returns the resulting package. The procedure stops recursion
5373 when @var{cut?} returns true for a given package.
5377 * package Reference:: The package data type.
5378 * origin Reference:: The origin data type.
5382 @node package Reference
5383 @subsection @code{package} Reference
5385 This section summarizes all the options available in @code{package}
5386 declarations (@pxref{Defining Packages}).
5388 @deftp {Data Type} package
5389 This is the data type representing a package recipe.
5393 The name of the package, as a string.
5395 @item @code{version}
5396 The version of the package, as a string.
5399 An object telling how the source code for the package should be
5400 acquired. Most of the time, this is an @code{origin} object, which
5401 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5402 can also be any other ``file-like'' object such as a @code{local-file},
5403 which denotes a file from the local file system (@pxref{G-Expressions,
5404 @code{local-file}}).
5406 @item @code{build-system}
5407 The build system that should be used to build the package (@pxref{Build
5410 @item @code{arguments} (default: @code{'()})
5411 The arguments that should be passed to the build system. This is a
5412 list, typically containing sequential keyword-value pairs.
5414 @item @code{inputs} (default: @code{'()})
5415 @itemx @code{native-inputs} (default: @code{'()})
5416 @itemx @code{propagated-inputs} (default: @code{'()})
5417 @cindex inputs, of packages
5418 These fields list dependencies of the package. Each one is a list of
5419 tuples, where each tuple has a label for the input (a string) as its
5420 first element, a package, origin, or derivation as its second element,
5421 and optionally the name of the output thereof that should be used, which
5422 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5423 more on package outputs). For example, the list below specifies three
5427 `(("libffi" ,libffi)
5428 ("libunistring" ,libunistring)
5429 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5432 @cindex cross compilation, package dependencies
5433 The distinction between @code{native-inputs} and @code{inputs} is
5434 necessary when considering cross-compilation. When cross-compiling,
5435 dependencies listed in @code{inputs} are built for the @emph{target}
5436 architecture; conversely, dependencies listed in @code{native-inputs}
5437 are built for the architecture of the @emph{build} machine.
5439 @code{native-inputs} is typically used to list tools needed at
5440 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5441 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5442 this area (@pxref{Invoking guix lint}).
5444 @anchor{package-propagated-inputs}
5445 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5446 specified packages will be automatically installed alongside the package
5447 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5448 package}}, for information on how @command{guix package} deals with
5451 For example this is necessary when a C/C++ library needs headers of
5452 another library to compile, or when a pkg-config file refers to another
5453 one @i{via} its @code{Requires} field.
5455 Another example where @code{propagated-inputs} is useful is for languages
5456 that lack a facility to record the run-time search path akin to the
5457 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5458 more. To ensure that libraries written in those languages can find
5459 library code they depend on at run time, run-time dependencies must be
5460 listed in @code{propagated-inputs} rather than @code{inputs}.
5462 @item @code{outputs} (default: @code{'("out")})
5463 The list of output names of the package. @xref{Packages with Multiple
5464 Outputs}, for typical uses of additional outputs.
5466 @item @code{native-search-paths} (default: @code{'()})
5467 @itemx @code{search-paths} (default: @code{'()})
5468 A list of @code{search-path-specification} objects describing
5469 search-path environment variables honored by the package.
5471 @item @code{replacement} (default: @code{#f})
5472 This must be either @code{#f} or a package object that will be used as a
5473 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5476 @item @code{synopsis}
5477 A one-line description of the package.
5479 @item @code{description}
5480 A more elaborate description of the package.
5482 @item @code{license}
5483 @cindex license, of packages
5484 The license of the package; a value from @code{(guix licenses)},
5485 or a list of such values.
5487 @item @code{home-page}
5488 The URL to the home-page of the package, as a string.
5490 @item @code{supported-systems} (default: @var{%supported-systems})
5491 The list of systems supported by the package, as strings of the form
5492 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5494 @item @code{maintainers} (default: @code{'()})
5495 The list of maintainers of the package, as @code{maintainer} objects.
5497 @item @code{location} (default: source location of the @code{package} form)
5498 The source location of the package. It is useful to override this when
5499 inheriting from another package, in which case this field is not
5500 automatically corrected.
5504 @deffn {Scheme Syntax} this-package
5505 When used in the @emph{lexical scope} of a package field definition, this
5506 identifier resolves to the package being defined.
5508 The example below shows how to add a package as a native input of itself when
5516 ;; When cross-compiled, Guile, for example, depends on
5517 ;; a native version of itself. Add it here.
5518 (native-inputs (if (%current-target-system)
5519 `(("self" ,this-package))
5523 It is an error to refer to @code{this-package} outside a package definition.
5526 @node origin Reference
5527 @subsection @code{origin} Reference
5529 This section summarizes all the options available in @code{origin}
5530 declarations (@pxref{Defining Packages}).
5532 @deftp {Data Type} origin
5533 This is the data type representing a source code origin.
5537 An object containing the URI of the source. The object type depends on
5538 the @code{method} (see below). For example, when using the
5539 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5540 values are: a URL represented as a string, or a list thereof.
5543 A procedure that handles the URI.
5548 @item @var{url-fetch} from @code{(guix download)}
5549 download a file from the HTTP, HTTPS, or FTP URL specified in the
5553 @item @var{git-fetch} from @code{(guix git-download)}
5554 clone the Git version control repository, and check out the revision
5555 specified in the @code{uri} field as a @code{git-reference} object; a
5556 @code{git-reference} looks like this:
5560 (url "git://git.debian.org/git/pkg-shadow/shadow")
5561 (commit "v4.1.5.1"))
5566 A bytevector containing the SHA-256 hash of the source. Typically the
5567 @code{base32} form is used here to generate the bytevector from a
5570 You can obtain this information using @code{guix download}
5571 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5574 @item @code{file-name} (default: @code{#f})
5575 The file name under which the source code should be saved. When this is
5576 @code{#f}, a sensible default value will be used in most cases. In case
5577 the source is fetched from a URL, the file name from the URL will be
5578 used. For version control checkouts, it is recommended to provide the
5579 file name explicitly because the default is not very descriptive.
5581 @item @code{patches} (default: @code{'()})
5582 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5583 file-like objects}) pointing to patches to be applied to the source.
5585 This list of patches must be unconditional. In particular, it cannot
5586 depend on the value of @code{%current-system} or
5587 @code{%current-target-system}.
5589 @item @code{snippet} (default: @code{#f})
5590 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5591 in the source directory. This is a convenient way to modify the source,
5592 sometimes more convenient than a patch.
5594 @item @code{patch-flags} (default: @code{'("-p1")})
5595 A list of command-line flags that should be passed to the @code{patch}
5598 @item @code{patch-inputs} (default: @code{#f})
5599 Input packages or derivations to the patching process. When this is
5600 @code{#f}, the usual set of inputs necessary for patching are provided,
5601 such as GNU@tie{}Patch.
5603 @item @code{modules} (default: @code{'()})
5604 A list of Guile modules that should be loaded during the patching
5605 process and while running the code in the @code{snippet} field.
5607 @item @code{patch-guile} (default: @code{#f})
5608 The Guile package that should be used in the patching process. When
5609 this is @code{#f}, a sensible default is used.
5615 @section Build Systems
5617 @cindex build system
5618 Each package definition specifies a @dfn{build system} and arguments for
5619 that build system (@pxref{Defining Packages}). This @code{build-system}
5620 field represents the build procedure of the package, as well as implicit
5621 dependencies of that build procedure.
5623 Build systems are @code{<build-system>} objects. The interface to
5624 create and manipulate them is provided by the @code{(guix build-system)}
5625 module, and actual build systems are exported by specific modules.
5627 @cindex bag (low-level package representation)
5628 Under the hood, build systems first compile package objects to
5629 @dfn{bags}. A @dfn{bag} is like a package, but with less
5630 ornamentation---in other words, a bag is a lower-level representation of
5631 a package, which includes all the inputs of that package, including some
5632 that were implicitly added by the build system. This intermediate
5633 representation is then compiled to a derivation (@pxref{Derivations}).
5635 Build systems accept an optional list of @dfn{arguments}. In package
5636 definitions, these are passed @i{via} the @code{arguments} field
5637 (@pxref{Defining Packages}). They are typically keyword arguments
5638 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5639 Guile Reference Manual}). The value of these arguments is usually
5640 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5641 by the daemon (@pxref{Derivations}).
5643 The main build system is @var{gnu-build-system}, which implements the
5644 standard build procedure for GNU and many other packages. It
5645 is provided by the @code{(guix build-system gnu)} module.
5647 @defvr {Scheme Variable} gnu-build-system
5648 @var{gnu-build-system} represents the GNU Build System, and variants
5649 thereof (@pxref{Configuration, configuration and makefile conventions,,
5650 standards, GNU Coding Standards}).
5652 @cindex build phases
5653 In a nutshell, packages using it are configured, built, and installed with
5654 the usual @code{./configure && make && make check && make install}
5655 command sequence. In practice, a few additional steps are often needed.
5656 All these steps are split up in separate @dfn{phases},
5657 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5658 modules for more details about the build phases.}:
5662 Unpack the source tarball, and change the current directory to the
5663 extracted source tree. If the source is actually a directory, copy it
5664 to the build tree, and enter that directory.
5666 @item patch-source-shebangs
5667 Patch shebangs encountered in source files so they refer to the right
5668 store file names. For instance, this changes @code{#!/bin/sh} to
5669 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
5672 Run the @file{configure} script with a number of default options, such
5673 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
5674 by the @code{#:configure-flags} argument.
5677 Run @code{make} with the list of flags specified with
5678 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
5679 (the default), build with @code{make -j}.
5682 Run @code{make check}, or some other target specified with
5683 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
5684 @code{#:parallel-tests?} argument is true (the default), run @code{make
5688 Run @code{make install} with the flags listed in @code{#:make-flags}.
5690 @item patch-shebangs
5691 Patch shebangs on the installed executable files.
5694 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
5695 is false), copying them to the @code{debug} output when available
5696 (@pxref{Installing Debugging Files}).
5699 @vindex %standard-phases
5700 The build-side module @code{(guix build gnu-build-system)} defines
5701 @var{%standard-phases} as the default list of build phases.
5702 @var{%standard-phases} is a list of symbol/procedure pairs, where the
5703 procedure implements the actual phase.
5705 The list of phases used for a particular package can be changed with the
5706 @code{#:phases} parameter. For instance, passing:
5709 #:phases (modify-phases %standard-phases (delete 'configure))
5712 means that all the phases described above will be used, except the
5713 @code{configure} phase.
5715 In addition, this build system ensures that the ``standard'' environment
5716 for GNU packages is available. This includes tools such as GCC, libc,
5717 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
5718 build-system gnu)} module for a complete list). We call these the
5719 @dfn{implicit inputs} of a package, because package definitions do not
5720 have to mention them.
5723 Other @code{<build-system>} objects are defined to support other
5724 conventions and tools used by free software packages. They inherit most
5725 of @var{gnu-build-system}, and differ mainly in the set of inputs
5726 implicitly added to the build process, and in the list of phases
5727 executed. Some of these build systems are listed below.
5729 @defvr {Scheme Variable} ant-build-system
5730 This variable is exported by @code{(guix build-system ant)}. It
5731 implements the build procedure for Java packages that can be built with
5732 @url{https://ant.apache.org/, Ant build tool}.
5734 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
5735 provided by the @code{icedtea} package to the set of inputs. Different
5736 packages can be specified with the @code{#:ant} and @code{#:jdk}
5737 parameters, respectively.
5739 When the original package does not provide a suitable Ant build file,
5740 the parameter @code{#:jar-name} can be used to generate a minimal Ant
5741 build file @file{build.xml} with tasks to build the specified jar
5742 archive. In this case the parameter @code{#:source-dir} can be used to
5743 specify the source sub-directory, defaulting to ``src''.
5745 The @code{#:main-class} parameter can be used with the minimal ant
5746 buildfile to specify the main class of the resulting jar. This makes the
5747 jar file executable. The @code{#:test-include} parameter can be used to
5748 specify the list of junit tests to run. It defaults to
5749 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
5750 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
5751 because abstract classes cannot be run as tests.
5753 The parameter @code{#:build-target} can be used to specify the Ant task
5754 that should be run during the @code{build} phase. By default the
5755 ``jar'' task will be run.
5759 @defvr {Scheme Variable} android-ndk-build-system
5760 @cindex Android distribution
5761 @cindex Android NDK build system
5762 This variable is exported by @code{(guix build-system android-ndk)}. It
5763 implements a build procedure for Android NDK (native development kit)
5764 packages using a Guix-specific build process.
5766 The build system assumes that packages install their public interface
5767 (header) files to the subdirectory "include" of the "out" output and
5768 their libraries to the subdirectory "lib" of the "out" output.
5770 It's also assumed that the union of all the dependencies of a package
5771 has no conflicting files.
5773 For the time being, cross-compilation is not supported - so right now
5774 the libraries and header files are assumed to be host tools.
5778 @defvr {Scheme Variable} asdf-build-system/source
5779 @defvrx {Scheme Variable} asdf-build-system/sbcl
5780 @defvrx {Scheme Variable} asdf-build-system/ecl
5782 These variables, exported by @code{(guix build-system asdf)}, implement
5783 build procedures for Common Lisp packages using
5784 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
5785 definition facility for Common Lisp programs and libraries.
5787 The @code{asdf-build-system/source} system installs the packages in
5788 source form, and can be loaded using any common lisp implementation, via
5789 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
5790 systems in the format which a particular implementation understands.
5791 These build systems can also be used to produce executable programs, or
5792 lisp images which contain a set of packages pre-loaded.
5794 The build system uses naming conventions. For binary packages, the
5795 package name should be prefixed with the lisp implementation, such as
5796 @code{sbcl-} for @code{asdf-build-system/sbcl}.
5798 Additionally, the corresponding source package should be labeled using
5799 the same convention as python packages (see @ref{Python Modules}), using
5800 the @code{cl-} prefix.
5802 For binary packages, each system should be defined as a Guix package.
5803 If one package @code{origin} contains several systems, package variants
5804 can be created in order to build all the systems. Source packages,
5805 which use @code{asdf-build-system/source}, may contain several systems.
5807 In order to create executable programs and images, the build-side
5808 procedures @code{build-program} and @code{build-image} can be used.
5809 They should be called in a build phase after the @code{create-symlinks}
5810 phase, so that the system which was just built can be used within the
5811 resulting image. @code{build-program} requires a list of Common Lisp
5812 expressions to be passed as the @code{#:entry-program} argument.
5814 If the system is not defined within its own @code{.asd} file of the same
5815 name, then the @code{#:asd-file} parameter should be used to specify
5816 which file the system is defined in. Furthermore, if the package
5817 defines a system for its tests in a separate file, it will be loaded
5818 before the tests are run if it is specified by the
5819 @code{#:test-asd-file} parameter. If it is not set, the files
5820 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
5821 and @code{test.asd} will be tried if they exist.
5823 If for some reason the package must be named in a different way than the
5824 naming conventions suggest, the @code{#:asd-system-name} parameter can
5825 be used to specify the name of the system.
5829 @defvr {Scheme Variable} cargo-build-system
5830 @cindex Rust programming language
5831 @cindex Cargo (Rust build system)
5832 This variable is exported by @code{(guix build-system cargo)}. It
5833 supports builds of packages using Cargo, the build tool of the
5834 @uref{https://www.rust-lang.org, Rust programming language}.
5836 It adds @code{rustc} and @code{cargo} to the set of inputs.
5837 A different Rust package can be specified with the @code{#:rust} parameter.
5839 Regular cargo dependencies should be added to the package definition via the
5840 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
5841 spec can be a package or a source definition. Note that the spec must
5842 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
5843 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
5844 should be added to the package definition via the
5845 @code{#:cargo-development-inputs} parameter.
5847 In its @code{configure} phase, this build system will make any source inputs
5848 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
5849 parameters available to cargo. The @code{install} phase installs any crate
5850 the binaries if they are defined by the crate.
5853 @cindex Clojure (programming language)
5854 @cindex simple Clojure build system
5855 @defvr {Scheme Variable} clojure-build-system
5856 This variable is exported by @code{(guix build-system clojure)}. It implements
5857 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
5858 using plain old @code{compile} in Clojure. Cross-compilation is not supported
5861 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
5862 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
5863 @code{#:zip} parameters, respectively.
5865 A list of source directories, test directories and jar names can be specified
5866 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
5867 parameters, respectively. Compile directory and main class can be specified
5868 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
5869 Other parameters are documented below.
5871 This build system is an extension of @var{ant-build-system}, but with the
5872 following phases changed:
5877 This phase calls @code{compile} in Clojure to compile source files and runs
5878 @command{jar} to create jars from both source files and compiled files
5879 according to the include list and exclude list specified in
5880 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
5881 has priority over the include list. These lists consist of symbols
5882 representing Clojure libraries or the special keyword @code{#:all} representing
5883 all Clojure libraries found under the source directories. The parameter
5884 @code{#:omit-source?} decides if source should be included into the jars.
5887 This phase runs tests according to the include list and exclude list specified
5888 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
5889 meanings are analogous to that of @code{#:aot-include} and
5890 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
5891 stands for all Clojure libraries found under the test directories. The
5892 parameter @code{#:tests?} decides if tests should be run.
5895 This phase installs all jars built previously.
5898 Apart from the above, this build system also contains an additional phase:
5903 This phase installs all top-level files with base name matching
5904 @var{%doc-regex}. A different regex can be specified with the
5905 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
5906 directories specified in @code{#:doc-dirs} are installed as well.
5910 @defvr {Scheme Variable} cmake-build-system
5911 This variable is exported by @code{(guix build-system cmake)}. It
5912 implements the build procedure for packages using the
5913 @url{https://www.cmake.org, CMake build tool}.
5915 It automatically adds the @code{cmake} package to the set of inputs.
5916 Which package is used can be specified with the @code{#:cmake}
5919 The @code{#:configure-flags} parameter is taken as a list of flags
5920 passed to the @command{cmake} command. The @code{#:build-type}
5921 parameter specifies in abstract terms the flags passed to the compiler;
5922 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
5923 debugging information''), which roughly means that code is compiled with
5924 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
5927 @defvr {Scheme Variable} dune-build-system
5928 This variable is exported by @code{(guix build-system dune)}. It
5929 supports builds of packages using @uref{https://dune.build/, Dune}, a build
5930 tool for the OCaml programming language. It is implemented as an extension
5931 of the @code{ocaml-build-system} which is described below. As such, the
5932 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
5935 It automatically adds the @code{dune} package to the set of inputs.
5936 Which package is used can be specified with the @code{#:dune}
5939 There is no @code{configure} phase because dune packages typically don't
5940 need to be configured. The @code{#:build-flags} parameter is taken as a
5941 list of flags passed to the @code{dune} command during the build.
5943 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
5944 command instead of the more recent @code{dune} command while building
5945 a package. Its default value is @code{#f}.
5947 The @code{#:package} parameter can be passed to specify a package name, which
5948 is useful when a package contains multiple packages and you want to build
5949 only one of them. This is equivalent to passing the @code{-p} argument to
5953 @defvr {Scheme Variable} go-build-system
5954 This variable is exported by @code{(guix build-system go)}. It
5955 implements a build procedure for Go packages using the standard
5956 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
5957 Go build mechanisms}.
5959 The user is expected to provide a value for the key @code{#:import-path}
5960 and, in some cases, @code{#:unpack-path}. The
5961 @url{https://golang.org/doc/code.html#ImportPaths, import path}
5962 corresponds to the file system path expected by the package's build
5963 scripts and any referring packages, and provides a unique way to
5964 refer to a Go package. It is typically based on a combination of the
5965 package source code's remote URI and file system hierarchy structure. In
5966 some cases, you will need to unpack the package's source code to a
5967 different directory structure than the one indicated by the import path,
5968 and @code{#:unpack-path} should be used in such cases.
5970 Packages that provide Go libraries should install their source code into
5971 the built output. The key @code{#:install-source?}, which defaults to
5972 @code{#t}, controls whether or not the source code is installed. It can
5973 be set to @code{#f} for packages that only provide executable files.
5976 @defvr {Scheme Variable} glib-or-gtk-build-system
5977 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
5978 is intended for use with packages making use of GLib or GTK+.
5980 This build system adds the following two phases to the ones defined by
5981 @var{gnu-build-system}:
5984 @item glib-or-gtk-wrap
5985 The phase @code{glib-or-gtk-wrap} ensures that programs in
5986 @file{bin/} are able to find GLib ``schemas'' and
5987 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
5988 modules}. This is achieved by wrapping the programs in launch scripts
5989 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
5990 environment variables.
5992 It is possible to exclude specific package outputs from that wrapping
5993 process by listing their names in the
5994 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
5995 when an output is known not to contain any GLib or GTK+ binaries, and
5996 where wrapping would gratuitously add a dependency of that output on
5999 @item glib-or-gtk-compile-schemas
6000 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6001 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6002 GSettings schemas} of GLib are compiled. Compilation is performed by the
6003 @command{glib-compile-schemas} program. It is provided by the package
6004 @code{glib:bin} which is automatically imported by the build system.
6005 The @code{glib} package providing @command{glib-compile-schemas} can be
6006 specified with the @code{#:glib} parameter.
6009 Both phases are executed after the @code{install} phase.
6012 @defvr {Scheme Variable} guile-build-system
6013 This build system is for Guile packages that consist exclusively of Scheme
6014 code and that are so lean that they don't even have a makefile, let alone a
6015 @file{configure} script. It compiles Scheme code using @command{guild
6016 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6017 installs the @file{.scm} and @file{.go} files in the right place. It also
6018 installs documentation.
6020 This build system supports cross-compilation by using the @code{--target}
6021 option of @command{guild compile}.
6023 Packages built with @code{guile-build-system} must provide a Guile package in
6024 their @code{native-inputs} field.
6027 @defvr {Scheme Variable} minify-build-system
6028 This variable is exported by @code{(guix build-system minify)}. It
6029 implements a minification procedure for simple JavaScript packages.
6031 It adds @code{uglify-js} to the set of inputs and uses it to compress
6032 all JavaScript files in the @file{src} directory. A different minifier
6033 package can be specified with the @code{#:uglify-js} parameter, but it
6034 is expected that the package writes the minified code to the standard
6037 When the input JavaScript files are not all located in the @file{src}
6038 directory, the parameter @code{#:javascript-files} can be used to
6039 specify a list of file names to feed to the minifier.
6042 @defvr {Scheme Variable} ocaml-build-system
6043 This variable is exported by @code{(guix build-system ocaml)}. It implements
6044 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6045 of choosing the correct set of commands to run for each package. OCaml
6046 packages can expect many different commands to be run. This build system will
6049 When the package has a @file{setup.ml} file present at the top-level, it will
6050 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6051 @code{ocaml setup.ml -install}. The build system will assume that this file
6052 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6053 care of setting the prefix and enabling tests if they are not disabled. You
6054 can pass configure and build flags with the @code{#:configure-flags} and
6055 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6056 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6057 bypass this system in the build and install phases.
6059 When the package has a @file{configure} file, it is assumed that it is a
6060 hand-made configure script that requires a different argument format than
6061 in the @code{gnu-build-system}. You can add more flags with the
6062 @code{#:configure-flags} key.
6064 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6065 @code{#t}), it will be used and more flags can be passed to the build and
6066 install phases with the @code{#:make-flags} key.
6068 Finally, some packages do not have these files and use a somewhat standard
6069 location for its build system. In that case, the build system will run
6070 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6071 providing the path to the required findlib module. Additional flags can
6072 be passed via the @code{#:build-flags} key. Install is taken care of by
6073 @command{opam-installer}. In this case, the @code{opam} package must
6074 be added to the @code{native-inputs} field of the package definition.
6076 Note that most OCaml packages assume they will be installed in the same
6077 directory as OCaml, which is not what we want in guix. In particular, they
6078 will install @file{.so} files in their module's directory, which is usually
6079 fine because it is in the OCaml compiler directory. In guix though, these
6080 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6081 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6082 @file{.so} libraries should be installed.
6085 @defvr {Scheme Variable} python-build-system
6086 This variable is exported by @code{(guix build-system python)}. It
6087 implements the more or less standard build procedure used by Python
6088 packages, which consists in running @code{python setup.py build} and
6089 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6091 For packages that install stand-alone Python programs under @code{bin/},
6092 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6093 environment variable points to all the Python libraries they depend on.
6095 Which Python package is used to perform the build can be specified with
6096 the @code{#:python} parameter. This is a useful way to force a package
6097 to be built for a specific version of the Python interpreter, which
6098 might be necessary if the package is only compatible with a single
6099 interpreter version.
6101 By default guix calls @code{setup.py} under control of
6102 @code{setuptools}, much like @command{pip} does. Some packages are not
6103 compatible with setuptools (and pip), thus you can disable this by
6104 setting the @code{#:use-setuptools} parameter to @code{#f}.
6107 @defvr {Scheme Variable} perl-build-system
6108 This variable is exported by @code{(guix build-system perl)}. It
6109 implements the standard build procedure for Perl packages, which either
6110 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6111 followed by @code{Build} and @code{Build install}; or in running
6112 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6113 @code{make} and @code{make install}, depending on which of
6114 @code{Build.PL} or @code{Makefile.PL} is present in the package
6115 distribution. Preference is given to the former if both @code{Build.PL}
6116 and @code{Makefile.PL} exist in the package distribution. This
6117 preference can be reversed by specifying @code{#t} for the
6118 @code{#:make-maker?} parameter.
6120 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6121 passes flags specified by the @code{#:make-maker-flags} or
6122 @code{#:module-build-flags} parameter, respectively.
6124 Which Perl package is used can be specified with @code{#:perl}.
6127 @defvr {Scheme Variable} r-build-system
6128 This variable is exported by @code{(guix build-system r)}. It
6129 implements the build procedure used by @uref{https://r-project.org, R}
6130 packages, which essentially is little more than running @code{R CMD
6131 INSTALL --library=/gnu/store/@dots{}} in an environment where
6132 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6133 are run after installation using the R function
6134 @code{tools::testInstalledPackage}.
6137 @defvr {Scheme Variable} rakudo-build-system
6138 This variable is exported by @code{(guix build-system rakudo)}. It
6139 implements the build procedure used by @uref{https://rakudo.org/,
6140 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6141 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6142 installs the binaries, library files and the resources, as well as wrap
6143 the files under the @code{bin/} directory. Tests can be skipped by
6144 passing @code{#f} to the @code{tests?} parameter.
6146 Which rakudo package is used can be specified with @code{rakudo}.
6147 Which perl6-tap-harness package used for the tests can be specified with
6148 @code{#:prove6} or removed by passing @code{#f} to the
6149 @code{with-prove6?} parameter.
6150 Which perl6-zef package used for tests and installing can be specified
6151 with @code{#:zef} or removed by passing @code{#f} to the
6152 @code{with-zef?} parameter.
6155 @defvr {Scheme Variable} texlive-build-system
6156 This variable is exported by @code{(guix build-system texlive)}. It is
6157 used to build TeX packages in batch mode with a specified engine. The
6158 build system sets the @code{TEXINPUTS} variable to find all TeX source
6159 files in the inputs.
6161 By default it runs @code{luatex} on all files ending on @code{ins}. A
6162 different engine and format can be specified with the
6163 @code{#:tex-format} argument. Different build targets can be specified
6164 with the @code{#:build-targets} argument, which expects a list of file
6165 names. The build system adds only @code{texlive-bin} and
6166 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6167 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6168 and @code{#:texlive-latex-base}, respectively.
6170 The @code{#:tex-directory} parameter tells the build system where to
6171 install the built files under the texmf tree.
6174 @defvr {Scheme Variable} ruby-build-system
6175 This variable is exported by @code{(guix build-system ruby)}. It
6176 implements the RubyGems build procedure used by Ruby packages, which
6177 involves running @code{gem build} followed by @code{gem install}.
6179 The @code{source} field of a package that uses this build system
6180 typically references a gem archive, since this is the format that Ruby
6181 developers use when releasing their software. The build system unpacks
6182 the gem archive, potentially patches the source, runs the test suite,
6183 repackages the gem, and installs it. Additionally, directories and
6184 tarballs may be referenced to allow building unreleased gems from Git or
6185 a traditional source release tarball.
6187 Which Ruby package is used can be specified with the @code{#:ruby}
6188 parameter. A list of additional flags to be passed to the @command{gem}
6189 command can be specified with the @code{#:gem-flags} parameter.
6192 @defvr {Scheme Variable} waf-build-system
6193 This variable is exported by @code{(guix build-system waf)}. It
6194 implements a build procedure around the @code{waf} script. The common
6195 phases---@code{configure}, @code{build}, and @code{install}---are
6196 implemented by passing their names as arguments to the @code{waf}
6199 The @code{waf} script is executed by the Python interpreter. Which
6200 Python package is used to run the script can be specified with the
6201 @code{#:python} parameter.
6204 @defvr {Scheme Variable} scons-build-system
6205 This variable is exported by @code{(guix build-system scons)}. It
6206 implements the build procedure used by the SCons software construction
6207 tool. This build system runs @code{scons} to build the package,
6208 @code{scons test} to run tests, and then @code{scons install} to install
6211 Additional flags to be passed to @code{scons} can be specified with the
6212 @code{#:scons-flags} parameter. The version of Python used to run SCons
6213 can be specified by selecting the appropriate SCons package with the
6214 @code{#:scons} parameter.
6217 @defvr {Scheme Variable} haskell-build-system
6218 This variable is exported by @code{(guix build-system haskell)}. It
6219 implements the Cabal build procedure used by Haskell packages, which
6220 involves running @code{runhaskell Setup.hs configure
6221 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6222 Instead of installing the package by running @code{runhaskell Setup.hs
6223 install}, to avoid trying to register libraries in the read-only
6224 compiler store directory, the build system uses @code{runhaskell
6225 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6226 addition, the build system generates the package documentation by
6227 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6228 is passed. Optional Haddock parameters can be passed with the help of
6229 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6230 not found, the build system looks for @code{Setup.lhs} instead.
6232 Which Haskell compiler is used can be specified with the @code{#:haskell}
6233 parameter which defaults to @code{ghc}.
6236 @defvr {Scheme Variable} dub-build-system
6237 This variable is exported by @code{(guix build-system dub)}. It
6238 implements the Dub build procedure used by D packages, which
6239 involves running @code{dub build} and @code{dub run}.
6240 Installation is done by copying the files manually.
6242 Which D compiler is used can be specified with the @code{#:ldc}
6243 parameter which defaults to @code{ldc}.
6246 @defvr {Scheme Variable} emacs-build-system
6247 This variable is exported by @code{(guix build-system emacs)}. It
6248 implements an installation procedure similar to the packaging system
6249 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6251 It first creates the @code{@var{package}-autoloads.el} file, then it
6252 byte compiles all Emacs Lisp files. Differently from the Emacs
6253 packaging system, the Info documentation files are moved to the standard
6254 documentation directory and the @file{dir} file is deleted. Each
6255 package is installed in its own directory under
6256 @file{share/emacs/site-lisp/guix.d}.
6259 @defvr {Scheme Variable} font-build-system
6260 This variable is exported by @code{(guix build-system font)}. It
6261 implements an installation procedure for font packages where upstream
6262 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6263 need to be copied into place. It copies font files to standard
6264 locations in the output directory.
6267 @defvr {Scheme Variable} meson-build-system
6268 This variable is exported by @code{(guix build-system meson)}. It
6269 implements the build procedure for packages that use
6270 @url{https://mesonbuild.com, Meson} as their build system.
6272 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6273 of inputs, and they can be changed with the parameters @code{#:meson}
6274 and @code{#:ninja} if needed. The default Meson is
6275 @code{meson-for-build}, which is special because it doesn't clear the
6276 @code{RUNPATH} of binaries and libraries when they are installed.
6278 This build system is an extension of @var{gnu-build-system}, but with the
6279 following phases changed to some specific for Meson:
6284 The phase runs @code{meson} with the flags specified in
6285 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6286 @code{plain} unless something else is specified in @code{#:build-type}.
6289 The phase runs @code{ninja} to build the package in parallel by default, but
6290 this can be changed with @code{#:parallel-build?}.
6293 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6294 which is @code{"test"} by default.
6297 The phase runs @code{ninja install} and can not be changed.
6300 Apart from that, the build system also adds the following phases:
6305 This phase ensures that all binaries can find the libraries they need.
6306 It searches for required libraries in subdirectories of the package being
6307 built, and adds those to @code{RUNPATH} where needed. It also removes
6308 references to libraries left over from the build phase by
6309 @code{meson-for-build}, such as test dependencies, that aren't actually
6310 required for the program to run.
6312 @item glib-or-gtk-wrap
6313 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6314 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6316 @item glib-or-gtk-compile-schemas
6317 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6318 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6322 @defvr {Scheme Variable} linux-module-build-system
6323 @var{linux-module-build-system} allows building Linux kernel modules.
6325 @cindex build phases
6326 This build system is an extension of @var{gnu-build-system}, but with the
6327 following phases changed:
6332 This phase configures the environment so that the Linux kernel's Makefile
6333 can be used to build the external kernel module.
6336 This phase uses the Linux kernel's Makefile in order to build the external
6340 This phase uses the Linux kernel's Makefile in order to install the external
6344 It is possible and useful to specify the Linux kernel to use for building
6345 the module (in the "arguments" form of a package using the
6346 linux-module-build-system, use the key #:linux to specify it).
6349 @defvr {Scheme Variable} node-build-system
6350 This variable is exported by @code{(guix build-system node)}. It
6351 implements the build procedure used by @uref{http://nodejs.org,
6352 Node.js}, which implements an approximation of the @code{npm install}
6353 command, followed by an @code{npm test} command.
6355 Which Node.js package is used to interpret the @code{npm} commands can
6356 be specified with the @code{#:node} parameter which defaults to
6360 Lastly, for packages that do not need anything as sophisticated, a
6361 ``trivial'' build system is provided. It is trivial in the sense that
6362 it provides basically no support: it does not pull any implicit inputs,
6363 and does not have a notion of build phases.
6365 @defvr {Scheme Variable} trivial-build-system
6366 This variable is exported by @code{(guix build-system trivial)}.
6368 This build system requires a @code{#:builder} argument. This argument
6369 must be a Scheme expression that builds the package output(s)---as
6370 with @code{build-expression->derivation} (@pxref{Derivations,
6371 @code{build-expression->derivation}}).
6381 Conceptually, the @dfn{store} is the place where derivations that have
6382 been built successfully are stored---by default, @file{/gnu/store}.
6383 Sub-directories in the store are referred to as @dfn{store items} or
6384 sometimes @dfn{store paths}. The store has an associated database that
6385 contains information such as the store paths referred to by each store
6386 path, and the list of @emph{valid} store items---results of successful
6387 builds. This database resides in @file{@var{localstatedir}/guix/db},
6388 where @var{localstatedir} is the state directory specified @i{via}
6389 @option{--localstatedir} at configure time, usually @file{/var}.
6391 The store is @emph{always} accessed by the daemon on behalf of its clients
6392 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6393 connect to the daemon over a Unix-domain socket, send requests to it,
6394 and read the result---these are remote procedure calls, or RPCs.
6397 Users must @emph{never} modify files under @file{/gnu/store} directly.
6398 This would lead to inconsistencies and break the immutability
6399 assumptions of Guix's functional model (@pxref{Introduction}).
6401 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6402 how to check the integrity of the store and attempt recovery from
6403 accidental modifications.
6406 The @code{(guix store)} module provides procedures to connect to the
6407 daemon, and to perform RPCs. These are described below. By default,
6408 @code{open-connection}, and thus all the @command{guix} commands,
6409 connect to the local daemon or to the URI specified by the
6410 @code{GUIX_DAEMON_SOCKET} environment variable.
6412 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6413 When set, the value of this variable should be a file name or a URI
6414 designating the daemon endpoint. When it is a file name, it denotes a
6415 Unix-domain socket to connect to. In addition to file names, the
6416 supported URI schemes are:
6421 These are for Unix-domain sockets.
6422 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6423 @file{/var/guix/daemon-socket/socket}.
6426 @cindex daemon, remote access
6427 @cindex remote access to the daemon
6428 @cindex daemon, cluster setup
6429 @cindex clusters, daemon setup
6430 These URIs denote connections over TCP/IP, without encryption nor
6431 authentication of the remote host. The URI must specify the host name
6432 and optionally a port number (by default port 44146 is used):
6435 guix://master.guix.example.org:1234
6438 This setup is suitable on local networks, such as clusters, where only
6439 trusted nodes may connect to the build daemon at
6440 @code{master.guix.example.org}.
6442 The @code{--listen} option of @command{guix-daemon} can be used to
6443 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6447 @cindex SSH access to build daemons
6448 These URIs allow you to connect to a remote daemon over
6449 SSH@footnote{This feature requires Guile-SSH (@pxref{Requirements}).}.
6450 A typical URL might look like this:
6453 ssh://charlie@@guix.example.org:22
6456 As for @command{guix copy}, the usual OpenSSH client configuration files
6457 are honored (@pxref{Invoking guix copy}).
6460 Additional URI schemes may be supported in the future.
6462 @c XXX: Remove this note when the protocol incurs fewer round trips
6463 @c and when (guix derivations) no longer relies on file system access.
6465 The ability to connect to remote build daemons is considered
6466 experimental as of @value{VERSION}. Please get in touch with us to
6467 share any problems or suggestions you may have (@pxref{Contributing}).
6471 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6472 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6473 @var{reserve-space?} is true, instruct it to reserve a little bit of
6474 extra space on the file system so that the garbage collector can still
6475 operate should the disk become full. Return a server object.
6477 @var{file} defaults to @code{%default-socket-path}, which is the normal
6478 location given the options that were passed to @command{configure}.
6481 @deffn {Scheme Procedure} close-connection @var{server}
6482 Close the connection to @var{server}.
6485 @defvr {Scheme Variable} current-build-output-port
6486 This variable is bound to a SRFI-39 parameter, which refers to the port
6487 where build and error logs sent by the daemon should be written.
6490 Procedures that make RPCs all take a server object as their first
6493 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6494 @cindex invalid store items
6495 Return @code{#t} when @var{path} designates a valid store item and
6496 @code{#f} otherwise (an invalid item may exist on disk but still be
6497 invalid, for instance because it is the result of an aborted or failed
6500 A @code{&store-protocol-error} condition is raised if @var{path} is not
6501 prefixed by the store directory (@file{/gnu/store}).
6504 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6505 Add @var{text} under file @var{name} in the store, and return its store
6506 path. @var{references} is the list of store paths referred to by the
6507 resulting store path.
6510 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6512 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6513 file names, or derivation/output pairs, using the specified
6514 @var{mode}---@code{(build-mode normal)} by default.
6517 Note that the @code{(guix monads)} module provides a monad as well as
6518 monadic versions of the above procedures, with the goal of making it
6519 more convenient to work with code that accesses the store (@pxref{The
6523 @i{This section is currently incomplete.}
6526 @section Derivations
6529 Low-level build actions and the environment in which they are performed
6530 are represented by @dfn{derivations}. A derivation contains the
6531 following pieces of information:
6535 The outputs of the derivation---derivations produce at least one file or
6536 directory in the store, but may produce more.
6539 @cindex build-time dependencies
6540 @cindex dependencies, build-time
6541 The inputs of the derivations---i.e., its build-time dependencies---which may
6542 be other derivations or plain files in the store (patches, build scripts,
6546 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
6549 The file name of a build script in the store, along with the arguments
6553 A list of environment variables to be defined.
6557 @cindex derivation path
6558 Derivations allow clients of the daemon to communicate build actions to
6559 the store. They exist in two forms: as an in-memory representation,
6560 both on the client- and daemon-side, and as files in the store whose
6561 name end in @code{.drv}---these files are referred to as @dfn{derivation
6562 paths}. Derivations paths can be passed to the @code{build-derivations}
6563 procedure to perform the build actions they prescribe (@pxref{The
6566 @cindex fixed-output derivations
6567 Operations such as file downloads and version-control checkouts for
6568 which the expected content hash is known in advance are modeled as
6569 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
6570 of a fixed-output derivation are independent of its inputs---e.g., a
6571 source code download produces the same result regardless of the download
6572 method and tools being used.
6575 @cindex run-time dependencies
6576 @cindex dependencies, run-time
6577 The outputs of derivations---i.e., the build results---have a set of
6578 @dfn{references}, as reported by the @code{references} RPC or the
6579 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
6580 are the set of run-time dependencies of the build results. References are a
6581 subset of the inputs of the derivation; this subset is automatically computed
6582 by the build daemon by scanning all the files in the outputs.
6584 The @code{(guix derivations)} module provides a representation of
6585 derivations as Scheme objects, along with procedures to create and
6586 otherwise manipulate derivations. The lowest-level primitive to create
6587 a derivation is the @code{derivation} procedure:
6589 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
6590 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6591 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
6592 [#:system (%current-system)] [#:references-graphs #f] @
6593 [#:allowed-references #f] [#:disallowed-references #f] @
6594 [#:leaked-env-vars #f] [#:local-build? #f] @
6595 [#:substitutable? #t] [#:properties '()]
6596 Build a derivation with the given arguments, and return the resulting
6597 @code{<derivation>} object.
6599 When @var{hash} and @var{hash-algo} are given, a
6600 @dfn{fixed-output derivation} is created---i.e., one whose result is
6601 known in advance, such as a file download. If, in addition,
6602 @var{recursive?} is true, then that fixed output may be an executable
6603 file or a directory and @var{hash} must be the hash of an archive
6604 containing this output.
6606 When @var{references-graphs} is true, it must be a list of file
6607 name/store path pairs. In that case, the reference graph of each store
6608 path is exported in the build environment in the corresponding file, in
6609 a simple text format.
6611 When @var{allowed-references} is true, it must be a list of store items
6612 or outputs that the derivation's output may refer to. Likewise,
6613 @var{disallowed-references}, if true, must be a list of things the
6614 outputs may @emph{not} refer to.
6616 When @var{leaked-env-vars} is true, it must be a list of strings
6617 denoting environment variables that are allowed to ``leak'' from the
6618 daemon's environment to the build environment. This is only applicable
6619 to fixed-output derivations---i.e., when @var{hash} is true. The main
6620 use is to allow variables such as @code{http_proxy} to be passed to
6621 derivations that download files.
6623 When @var{local-build?} is true, declare that the derivation is not a
6624 good candidate for offloading and should rather be built locally
6625 (@pxref{Daemon Offload Setup}). This is the case for small derivations
6626 where the costs of data transfers would outweigh the benefits.
6628 When @var{substitutable?} is false, declare that substitutes of the
6629 derivation's output should not be used (@pxref{Substitutes}). This is
6630 useful, for instance, when building packages that capture details of the
6631 host CPU instruction set.
6633 @var{properties} must be an association list describing ``properties'' of the
6634 derivation. It is kept as-is, uninterpreted, in the derivation.
6638 Here's an example with a shell script as its builder, assuming
6639 @var{store} is an open connection to the daemon, and @var{bash} points
6640 to a Bash executable in the store:
6643 (use-modules (guix utils)
6647 (let ((builder ; add the Bash script to the store
6648 (add-text-to-store store "my-builder.sh"
6649 "echo hello world > $out\n" '())))
6650 (derivation store "foo"
6651 bash `("-e" ,builder)
6652 #:inputs `((,bash) (,builder))
6653 #:env-vars '(("HOME" . "/homeless"))))
6654 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
6657 As can be guessed, this primitive is cumbersome to use directly. A
6658 better approach is to write build scripts in Scheme, of course! The
6659 best course of action for that is to write the build code as a
6660 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
6661 information, @pxref{G-Expressions}.
6663 Once upon a time, @code{gexp->derivation} did not exist and constructing
6664 derivations with build code written in Scheme was achieved with
6665 @code{build-expression->derivation}, documented below. This procedure
6666 is now deprecated in favor of the much nicer @code{gexp->derivation}.
6668 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
6669 @var{name} @var{exp} @
6670 [#:system (%current-system)] [#:inputs '()] @
6671 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6672 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
6673 [#:references-graphs #f] [#:allowed-references #f] @
6674 [#:disallowed-references #f] @
6675 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
6676 Return a derivation that executes Scheme expression @var{exp} as a
6677 builder for derivation @var{name}. @var{inputs} must be a list of
6678 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
6679 @code{"out"} is assumed. @var{modules} is a list of names of Guile
6680 modules from the current search path to be copied in the store,
6681 compiled, and made available in the load path during the execution of
6682 @var{exp}---e.g., @code{((guix build utils) (guix build
6683 gnu-build-system))}.
6685 @var{exp} is evaluated in an environment where @code{%outputs} is bound
6686 to a list of output/path pairs, and where @code{%build-inputs} is bound
6687 to a list of string/output-path pairs made from @var{inputs}.
6688 Optionally, @var{env-vars} is a list of string pairs specifying the name
6689 and value of environment variables visible to the builder. The builder
6690 terminates by passing the result of @var{exp} to @code{exit}; thus, when
6691 @var{exp} returns @code{#f}, the build is considered to have failed.
6693 @var{exp} is built using @var{guile-for-build} (a derivation). When
6694 @var{guile-for-build} is omitted or is @code{#f}, the value of the
6695 @code{%guile-for-build} fluid is used instead.
6697 See the @code{derivation} procedure for the meaning of
6698 @var{references-graphs}, @var{allowed-references},
6699 @var{disallowed-references}, @var{local-build?}, and
6700 @var{substitutable?}.
6704 Here's an example of a single-output derivation that creates a directory
6705 containing one file:
6708 (let ((builder '(let ((out (assoc-ref %outputs "out")))
6709 (mkdir out) ; create /gnu/store/@dots{}-goo
6710 (call-with-output-file (string-append out "/test")
6712 (display '(hello guix) p))))))
6713 (build-expression->derivation store "goo" builder))
6715 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
6719 @node The Store Monad
6720 @section The Store Monad
6724 The procedures that operate on the store described in the previous
6725 sections all take an open connection to the build daemon as their first
6726 argument. Although the underlying model is functional, they either have
6727 side effects or depend on the current state of the store.
6729 The former is inconvenient: the connection to the build daemon has to be
6730 carried around in all those functions, making it impossible to compose
6731 functions that do not take that parameter with functions that do. The
6732 latter can be problematic: since store operations have side effects
6733 and/or depend on external state, they have to be properly sequenced.
6735 @cindex monadic values
6736 @cindex monadic functions
6737 This is where the @code{(guix monads)} module comes in. This module
6738 provides a framework for working with @dfn{monads}, and a particularly
6739 useful monad for our uses, the @dfn{store monad}. Monads are a
6740 construct that allows two things: associating ``context'' with values
6741 (in our case, the context is the store), and building sequences of
6742 computations (here computations include accesses to the store). Values
6743 in a monad---values that carry this additional context---are called
6744 @dfn{monadic values}; procedures that return such values are called
6745 @dfn{monadic procedures}.
6747 Consider this ``normal'' procedure:
6750 (define (sh-symlink store)
6751 ;; Return a derivation that symlinks the 'bash' executable.
6752 (let* ((drv (package-derivation store bash))
6753 (out (derivation->output-path drv))
6754 (sh (string-append out "/bin/bash")))
6755 (build-expression->derivation store "sh"
6756 `(symlink ,sh %output))))
6759 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
6760 as a monadic function:
6763 (define (sh-symlink)
6764 ;; Same, but return a monadic value.
6765 (mlet %store-monad ((drv (package->derivation bash)))
6766 (gexp->derivation "sh"
6767 #~(symlink (string-append #$drv "/bin/bash")
6771 There are several things to note in the second version: the @code{store}
6772 parameter is now implicit and is ``threaded'' in the calls to the
6773 @code{package->derivation} and @code{gexp->derivation} monadic
6774 procedures, and the monadic value returned by @code{package->derivation}
6775 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
6777 As it turns out, the call to @code{package->derivation} can even be
6778 omitted since it will take place implicitly, as we will see later
6779 (@pxref{G-Expressions}):
6782 (define (sh-symlink)
6783 (gexp->derivation "sh"
6784 #~(symlink (string-append #$bash "/bin/bash")
6789 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
6790 @c for the funny quote.
6791 Calling the monadic @code{sh-symlink} has no effect. As someone once
6792 said, ``you exit a monad like you exit a building on fire: by running''.
6793 So, to exit the monad and get the desired effect, one must use
6794 @code{run-with-store}:
6797 (run-with-store (open-connection) (sh-symlink))
6798 @result{} /gnu/store/...-sh-symlink
6801 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
6802 new ``meta-commands'' to make it easier to deal with monadic procedures:
6803 @code{run-in-store}, and @code{enter-store-monad}. The former is used
6804 to ``run'' a single monadic value through the store:
6807 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
6808 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6811 The latter enters a recursive REPL, where all the return values are
6812 automatically run through the store:
6815 scheme@@(guile-user)> ,enter-store-monad
6816 store-monad@@(guile-user) [1]> (package->derivation hello)
6817 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6818 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
6819 $3 = "/gnu/store/@dots{}-foo"
6820 store-monad@@(guile-user) [1]> ,q
6821 scheme@@(guile-user)>
6825 Note that non-monadic values cannot be returned in the
6826 @code{store-monad} REPL.
6828 The main syntactic forms to deal with monads in general are provided by
6829 the @code{(guix monads)} module and are described below.
6831 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
6832 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
6836 @deffn {Scheme Syntax} return @var{val}
6837 Return a monadic value that encapsulates @var{val}.
6840 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
6841 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
6842 procedures @var{mproc}@dots{}@footnote{This operation is commonly
6843 referred to as ``bind'', but that name denotes an unrelated procedure in
6844 Guile. Thus we use this somewhat cryptic symbol inherited from the
6845 Haskell language.}. There can be one @var{mproc} or several of them, as
6850 (with-monad %state-monad
6852 (lambda (x) (return (+ 1 x)))
6853 (lambda (x) (return (* 2 x)))))
6857 @result{} some-state
6861 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
6863 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
6865 Bind the variables @var{var} to the monadic values @var{mval} in
6866 @var{body}, which is a sequence of expressions. As with the bind
6867 operator, this can be thought of as ``unpacking'' the raw, non-monadic
6868 value ``contained'' in @var{mval} and making @var{var} refer to that
6869 raw, non-monadic value within the scope of the @var{body}. The form
6870 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
6871 @var{val}, as per @code{let}. The binding operations occur in sequence
6872 from left to right. The last expression of @var{body} must be a monadic
6873 expression, and its result will become the result of the @code{mlet} or
6874 @code{mlet*} when run in the @var{monad}.
6876 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
6877 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
6880 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
6881 Bind @var{mexp} and the following monadic expressions in sequence,
6882 returning the result of the last expression. Every expression in the
6883 sequence must be a monadic expression.
6885 This is akin to @code{mlet}, except that the return values of the
6886 monadic expressions are ignored. In that sense, it is analogous to
6887 @code{begin}, but applied to monadic expressions.
6890 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
6891 When @var{condition} is true, evaluate the sequence of monadic
6892 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6893 @var{condition} is false, return @code{*unspecified*} in the current
6894 monad. Every expression in the sequence must be a monadic expression.
6897 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
6898 When @var{condition} is false, evaluate the sequence of monadic
6899 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6900 @var{condition} is true, return @code{*unspecified*} in the current
6901 monad. Every expression in the sequence must be a monadic expression.
6905 The @code{(guix monads)} module provides the @dfn{state monad}, which
6906 allows an additional value---the state---to be @emph{threaded} through
6907 monadic procedure calls.
6909 @defvr {Scheme Variable} %state-monad
6910 The state monad. Procedures in the state monad can access and change
6911 the state that is threaded.
6913 Consider the example below. The @code{square} procedure returns a value
6914 in the state monad. It returns the square of its argument, but also
6915 increments the current state value:
6919 (mlet %state-monad ((count (current-state)))
6920 (mbegin %state-monad
6921 (set-current-state (+ 1 count))
6924 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
6929 When ``run'' through @var{%state-monad}, we obtain that additional state
6930 value, which is the number of @code{square} calls.
6933 @deffn {Monadic Procedure} current-state
6934 Return the current state as a monadic value.
6937 @deffn {Monadic Procedure} set-current-state @var{value}
6938 Set the current state to @var{value} and return the previous state as a
6942 @deffn {Monadic Procedure} state-push @var{value}
6943 Push @var{value} to the current state, which is assumed to be a list,
6944 and return the previous state as a monadic value.
6947 @deffn {Monadic Procedure} state-pop
6948 Pop a value from the current state and return it as a monadic value.
6949 The state is assumed to be a list.
6952 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
6953 Run monadic value @var{mval} starting with @var{state} as the initial
6954 state. Return two values: the resulting value, and the resulting state.
6957 The main interface to the store monad, provided by the @code{(guix
6958 store)} module, is as follows.
6960 @defvr {Scheme Variable} %store-monad
6961 The store monad---an alias for @var{%state-monad}.
6963 Values in the store monad encapsulate accesses to the store. When its
6964 effect is needed, a value of the store monad must be ``evaluated'' by
6965 passing it to the @code{run-with-store} procedure (see below.)
6968 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
6969 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
6970 open store connection.
6973 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
6974 Return as a monadic value the absolute file name in the store of the file
6975 containing @var{text}, a string. @var{references} is a list of store items that the
6976 resulting text file refers to; it defaults to the empty list.
6979 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
6980 Return as a monadic value the absolute file name in the store of the file
6981 containing @var{data}, a bytevector. @var{references} is a list of store
6982 items that the resulting binary file refers to; it defaults to the empty list.
6985 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
6986 [#:recursive? #t] [#:select? (const #t)]
6987 Return the name of @var{file} once interned in the store. Use
6988 @var{name} as its store name, or the basename of @var{file} if
6989 @var{name} is omitted.
6991 When @var{recursive?} is true, the contents of @var{file} are added
6992 recursively; if @var{file} designates a flat file and @var{recursive?}
6993 is true, its contents are added, and its permission bits are kept.
6995 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
6996 @var{stat})} for each directory entry, where @var{file} is the entry's
6997 absolute file name and @var{stat} is the result of @code{lstat}; exclude
6998 entries for which @var{select?} does not return true.
7000 The example below adds a file to the store, under two different names:
7003 (run-with-store (open-connection)
7004 (mlet %store-monad ((a (interned-file "README"))
7005 (b (interned-file "README" "LEGU-MIN")))
7006 (return (list a b))))
7008 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7013 The @code{(guix packages)} module exports the following package-related
7016 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7017 [#:system (%current-system)] [#:target #f] @
7020 value in the absolute file name of @var{file} within the @var{output}
7021 directory of @var{package}. When @var{file} is omitted, return the name
7022 of the @var{output} directory of @var{package}. When @var{target} is
7023 true, use it as a cross-compilation target triplet.
7026 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7027 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7028 @var{target} [@var{system}]
7029 Monadic version of @code{package-derivation} and
7030 @code{package-cross-derivation} (@pxref{Defining Packages}).
7035 @section G-Expressions
7037 @cindex G-expression
7038 @cindex build code quoting
7039 So we have ``derivations'', which represent a sequence of build actions
7040 to be performed to produce an item in the store (@pxref{Derivations}).
7041 These build actions are performed when asking the daemon to actually
7042 build the derivations; they are run by the daemon in a container
7043 (@pxref{Invoking guix-daemon}).
7045 @cindex strata of code
7046 It should come as no surprise that we like to write these build actions
7047 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7048 code@footnote{The term @dfn{stratum} in this context was coined by
7049 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7050 Kiselyov, who has written insightful
7051 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7052 on this topic}, refers to this kind of code generation as
7053 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7054 to the daemon, etc.---and the ``build code''---code that actually
7055 performs build actions, such as making directories, invoking
7056 @command{make}, etc.
7058 To describe a derivation and its build actions, one typically needs to
7059 embed build code inside host code. It boils down to manipulating build
7060 code as data, and the homoiconicity of Scheme---code has a direct
7061 representation as data---comes in handy for that. But we need more than
7062 the normal @code{quasiquote} mechanism in Scheme to construct build
7065 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7066 S-expressions adapted to build expressions. G-expressions, or
7067 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7068 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7069 @code{#$}, and @code{#$@@}), which are comparable to
7070 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7071 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7072 GNU Guile Reference Manual}). However, there are major differences:
7076 Gexps are meant to be written to a file and run or manipulated by other
7080 When a high-level object such as a package or derivation is unquoted
7081 inside a gexp, the result is as if its output file name had been
7085 Gexps carry information about the packages or derivations they refer to,
7086 and these dependencies are automatically added as inputs to the build
7087 processes that use them.
7090 @cindex lowering, of high-level objects in gexps
7091 This mechanism is not limited to package and derivation
7092 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7093 derivations or files in the store can be defined,
7094 such that these objects can also be inserted
7095 into gexps. For example, a useful type of high-level objects that can be
7096 inserted in a gexp is ``file-like objects'', which make it easy to
7097 add files to the store and to refer to them in
7098 derivations and such (see @code{local-file} and @code{plain-file}
7101 To illustrate the idea, here is an example of a gexp:
7108 (symlink (string-append #$coreutils "/bin/ls")
7112 This gexp can be passed to @code{gexp->derivation}; we obtain a
7113 derivation that builds a directory containing exactly one symlink to
7114 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7117 (gexp->derivation "the-thing" build-exp)
7120 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7121 substituted to the reference to the @var{coreutils} package in the
7122 actual build code, and @var{coreutils} is automatically made an input to
7123 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7124 output)}) is replaced by a string containing the directory name of the
7125 output of the derivation.
7127 @cindex cross compilation
7128 In a cross-compilation context, it is useful to distinguish between
7129 references to the @emph{native} build of a package---that can run on the
7130 host---versus references to cross builds of a package. To that end, the
7131 @code{#+} plays the same role as @code{#$}, but is a reference to a
7132 native package build:
7135 (gexp->derivation "vi"
7138 (system* (string-append #+coreutils "/bin/ln")
7140 (string-append #$emacs "/bin/emacs")
7141 (string-append #$output "/bin/vi")))
7142 #:target "mips64el-linux-gnu")
7146 In the example above, the native build of @var{coreutils} is used, so
7147 that @command{ln} can actually run on the host; but then the
7148 cross-compiled build of @var{emacs} is referenced.
7150 @cindex imported modules, for gexps
7151 @findex with-imported-modules
7152 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7153 able to use certain Guile modules from the ``host environment'' in the
7154 gexp, so those modules should be imported in the ``build environment''.
7155 The @code{with-imported-modules} form allows you to express that:
7158 (let ((build (with-imported-modules '((guix build utils))
7160 (use-modules (guix build utils))
7161 (mkdir-p (string-append #$output "/bin"))))))
7162 (gexp->derivation "empty-dir"
7165 (display "success!\n")
7170 In this example, the @code{(guix build utils)} module is automatically
7171 pulled into the isolated build environment of our gexp, such that
7172 @code{(use-modules (guix build utils))} works as expected.
7174 @cindex module closure
7175 @findex source-module-closure
7176 Usually you want the @emph{closure} of the module to be imported---i.e.,
7177 the module itself and all the modules it depends on---rather than just
7178 the module; failing to do that, attempts to use the module will fail
7179 because of missing dependent modules. The @code{source-module-closure}
7180 procedure computes the closure of a module by looking at its source file
7181 headers, which comes in handy in this case:
7184 (use-modules (guix modules)) ;for 'source-module-closure'
7186 (with-imported-modules (source-module-closure
7187 '((guix build utils)
7189 (gexp->derivation "something-with-vms"
7191 (use-modules (guix build utils)
7196 @cindex extensions, for gexps
7197 @findex with-extensions
7198 In the same vein, sometimes you want to import not just pure-Scheme
7199 modules, but also ``extensions'' such as Guile bindings to C libraries
7200 or other ``full-blown'' packages. Say you need the @code{guile-json}
7201 package available on the build side, here's how you would do it:
7204 (use-modules (gnu packages guile)) ;for 'guile-json'
7206 (with-extensions (list guile-json)
7207 (gexp->derivation "something-with-json"
7209 (use-modules (json))
7213 The syntactic form to construct gexps is summarized below.
7215 @deffn {Scheme Syntax} #~@var{exp}
7216 @deffnx {Scheme Syntax} (gexp @var{exp})
7217 Return a G-expression containing @var{exp}. @var{exp} may contain one
7218 or more of the following forms:
7222 @itemx (ungexp @var{obj})
7223 Introduce a reference to @var{obj}. @var{obj} may have one of the
7224 supported types, for example a package or a
7225 derivation, in which case the @code{ungexp} form is replaced by its
7226 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7228 If @var{obj} is a list, it is traversed and references to supported
7229 objects are substituted similarly.
7231 If @var{obj} is another gexp, its contents are inserted and its
7232 dependencies are added to those of the containing gexp.
7234 If @var{obj} is another kind of object, it is inserted as is.
7236 @item #$@var{obj}:@var{output}
7237 @itemx (ungexp @var{obj} @var{output})
7238 This is like the form above, but referring explicitly to the
7239 @var{output} of @var{obj}---this is useful when @var{obj} produces
7240 multiple outputs (@pxref{Packages with Multiple Outputs}).
7243 @itemx #+@var{obj}:output
7244 @itemx (ungexp-native @var{obj})
7245 @itemx (ungexp-native @var{obj} @var{output})
7246 Same as @code{ungexp}, but produces a reference to the @emph{native}
7247 build of @var{obj} when used in a cross compilation context.
7249 @item #$output[:@var{output}]
7250 @itemx (ungexp output [@var{output}])
7251 Insert a reference to derivation output @var{output}, or to the main
7252 output when @var{output} is omitted.
7254 This only makes sense for gexps passed to @code{gexp->derivation}.
7257 @itemx (ungexp-splicing @var{lst})
7258 Like the above, but splices the contents of @var{lst} inside the
7262 @itemx (ungexp-native-splicing @var{lst})
7263 Like the above, but refers to native builds of the objects listed in
7268 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7269 of the @code{gexp?} type (see below.)
7272 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7273 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7274 in their execution environment.
7276 Each item in @var{modules} can be the name of a module, such as
7277 @code{(guix build utils)}, or it can be a module name, followed by an
7278 arrow, followed by a file-like object:
7281 `((guix build utils)
7283 ((guix config) => ,(scheme-file "config.scm"
7284 #~(define-module @dots{}))))
7288 In the example above, the first two modules are taken from the search
7289 path, and the last one is created from the given file-like object.
7291 This form has @emph{lexical} scope: it has an effect on the gexps
7292 directly defined in @var{body}@dots{}, but not on those defined, say, in
7293 procedures called from @var{body}@dots{}.
7296 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7297 Mark the gexps defined in @var{body}@dots{} as requiring
7298 @var{extensions} in their build and execution environment.
7299 @var{extensions} is typically a list of package objects such as those
7300 defined in the @code{(gnu packages guile)} module.
7302 Concretely, the packages listed in @var{extensions} are added to the
7303 load path while compiling imported modules in @var{body}@dots{}; they
7304 are also added to the load path of the gexp returned by
7308 @deffn {Scheme Procedure} gexp? @var{obj}
7309 Return @code{#t} if @var{obj} is a G-expression.
7312 G-expressions are meant to be written to disk, either as code building
7313 some derivation, or as plain files in the store. The monadic procedures
7314 below allow you to do that (@pxref{The Store Monad}, for more
7315 information about monads.)
7317 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7318 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7319 [#:hash #f] [#:hash-algo #f] @
7320 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7321 [#:module-path @var{%load-path}] @
7322 [#:effective-version "2.2"] @
7323 [#:references-graphs #f] [#:allowed-references #f] @
7324 [#:disallowed-references #f] @
7325 [#:leaked-env-vars #f] @
7326 [#:script-name (string-append @var{name} "-builder")] @
7327 [#:deprecation-warnings #f] @
7328 [#:local-build? #f] [#:substitutable? #t] @
7329 [#:properties '()] [#:guile-for-build #f]
7330 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7331 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7332 stored in a file called @var{script-name}. When @var{target} is true,
7333 it is used as the cross-compilation target triplet for packages referred
7336 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7338 make @var{modules} available in the evaluation context of @var{exp};
7339 @var{modules} is a list of names of Guile modules searched in
7340 @var{module-path} to be copied in the store, compiled, and made available in
7341 the load path during the execution of @var{exp}---e.g., @code{((guix
7342 build utils) (guix build gnu-build-system))}.
7344 @var{effective-version} determines the string to use when adding extensions of
7345 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7347 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7350 When @var{references-graphs} is true, it must be a list of tuples of one of the
7354 (@var{file-name} @var{package})
7355 (@var{file-name} @var{package} @var{output})
7356 (@var{file-name} @var{derivation})
7357 (@var{file-name} @var{derivation} @var{output})
7358 (@var{file-name} @var{store-item})
7361 The right-hand-side of each element of @var{references-graphs} is automatically made
7362 an input of the build process of @var{exp}. In the build environment, each
7363 @var{file-name} contains the reference graph of the corresponding item, in a simple
7366 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7367 In the latter case, the list denotes store items that the result is allowed to
7368 refer to. Any reference to another store item will lead to a build error.
7369 Similarly for @var{disallowed-references}, which can list items that must not be
7370 referenced by the outputs.
7372 @var{deprecation-warnings} determines whether to show deprecation warnings while
7373 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7375 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7378 @cindex file-like objects
7379 The @code{local-file}, @code{plain-file}, @code{computed-file},
7380 @code{program-file}, and @code{scheme-file} procedures below return
7381 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7382 these objects lead to a file in the store. Consider this G-expression:
7385 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7386 #$(local-file "/tmp/my-nscd.conf"))
7389 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7390 to the store. Once expanded, for instance @i{via}
7391 @code{gexp->derivation}, the G-expression refers to that copy under
7392 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7393 does not have any effect on what the G-expression does.
7394 @code{plain-file} can be used similarly; it differs in that the file
7395 content is directly passed as a string.
7397 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7398 [#:recursive? #f] [#:select? (const #t)]
7399 Return an object representing local file @var{file} to add to the store; this
7400 object can be used in a gexp. If @var{file} is a relative file name, it is looked
7401 up relative to the source file where this form appears. @var{file} will be added to
7402 the store under @var{name}--by default the base name of @var{file}.
7404 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7405 designates a flat file and @var{recursive?} is true, its contents are added, and its
7406 permission bits are kept.
7408 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7409 @var{stat})} for each directory entry, where @var{file} is the entry's
7410 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7411 entries for which @var{select?} does not return true.
7413 This is the declarative counterpart of the @code{interned-file} monadic
7414 procedure (@pxref{The Store Monad, @code{interned-file}}).
7417 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7418 Return an object representing a text file called @var{name} with the given
7419 @var{content} (a string or a bytevector) to be added to the store.
7421 This is the declarative counterpart of @code{text-file}.
7424 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7425 [#:options '(#:local-build? #t)]
7426 Return an object representing the store item @var{name}, a file or
7427 directory computed by @var{gexp}. @var{options}
7428 is a list of additional arguments to pass to @code{gexp->derivation}.
7430 This is the declarative counterpart of @code{gexp->derivation}.
7433 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7434 [#:guile (default-guile)] [#:module-path %load-path]
7435 Return an executable script @var{name} that runs @var{exp} using
7436 @var{guile}, with @var{exp}'s imported modules in its search path.
7437 Look up @var{exp}'s modules in @var{module-path}.
7439 The example below builds a script that simply invokes the @command{ls}
7443 (use-modules (guix gexp) (gnu packages base))
7445 (gexp->script "list-files"
7446 #~(execl #$(file-append coreutils "/bin/ls")
7450 When ``running'' it through the store (@pxref{The Store Monad,
7451 @code{run-with-store}}), we obtain a derivation that produces an
7452 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7455 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7457 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7461 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7462 [#:guile #f] [#:module-path %load-path]
7463 Return an object representing the executable store item @var{name} that
7464 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7465 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7467 This is the declarative counterpart of @code{gexp->script}.
7470 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7471 [#:set-load-path? #t] [#:module-path %load-path] @
7473 [#:guile (default-guile)]
7474 Return a derivation that builds a file @var{name} containing @var{exp}.
7475 When @var{splice?} is true, @var{exp} is considered to be a list of
7476 expressions that will be spliced in the resulting file.
7478 When @var{set-load-path?} is true, emit code in the resulting file to
7479 set @code{%load-path} and @code{%load-compiled-path} to honor
7480 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7483 The resulting file holds references to all the dependencies of @var{exp}
7484 or a subset thereof.
7487 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7488 Return an object representing the Scheme file @var{name} that contains
7491 This is the declarative counterpart of @code{gexp->file}.
7494 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7495 Return as a monadic value a derivation that builds a text file
7496 containing all of @var{text}. @var{text} may list, in addition to
7497 strings, objects of any type that can be used in a gexp: packages,
7498 derivations, local file objects, etc. The resulting store file holds
7499 references to all these.
7501 This variant should be preferred over @code{text-file} anytime the file
7502 to create will reference items from the store. This is typically the
7503 case when building a configuration file that embeds store file names,
7507 (define (profile.sh)
7508 ;; Return the name of a shell script in the store that
7509 ;; initializes the 'PATH' environment variable.
7510 (text-file* "profile.sh"
7511 "export PATH=" coreutils "/bin:"
7512 grep "/bin:" sed "/bin\n"))
7515 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7516 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7517 preventing them from being garbage-collected during its lifetime.
7520 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7521 Return an object representing store file @var{name} containing
7522 @var{text}. @var{text} is a sequence of strings and file-like objects,
7526 (mixed-text-file "profile"
7527 "export PATH=" coreutils "/bin:" grep "/bin")
7530 This is the declarative counterpart of @code{text-file*}.
7533 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7534 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7535 Each item in @var{files} must be a two-element list where the first element is the
7536 file name to use in the new directory, and the second element is a gexp
7537 denoting the target file. Here's an example:
7541 `(("hosts" ,(plain-file "hosts"
7542 "127.0.0.1 localhost"))
7543 ("bashrc" ,(plain-file "bashrc"
7544 "alias ls='ls --color=auto'"))))
7547 This yields an @code{etc} directory containing these two files.
7550 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
7551 Return a directory that is the union of @var{things}, where @var{things} is a list of
7552 file-like objects denoting directories. For example:
7555 (directory-union "guile+emacs" (list guile emacs))
7558 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
7561 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
7562 Return a file-like object that expands to the concatenation of @var{obj}
7563 and @var{suffix}, where @var{obj} is a lowerable object and each
7564 @var{suffix} is a string.
7566 As an example, consider this gexp:
7569 (gexp->script "run-uname"
7570 #~(system* #$(file-append coreutils
7574 The same effect could be achieved with:
7577 (gexp->script "run-uname"
7578 #~(system* (string-append #$coreutils
7582 There is one difference though: in the @code{file-append} case, the
7583 resulting script contains the absolute file name as a string, whereas in
7584 the second case, the resulting script contains a @code{(string-append
7585 @dots{})} expression to construct the file name @emph{at run time}.
7589 Of course, in addition to gexps embedded in ``host'' code, there are
7590 also modules containing build tools. To make it clear that they are
7591 meant to be used in the build stratum, these modules are kept in the
7592 @code{(guix build @dots{})} name space.
7594 @cindex lowering, of high-level objects in gexps
7595 Internally, high-level objects are @dfn{lowered}, using their compiler,
7596 to either derivations or store items. For instance, lowering a package
7597 yields a derivation, and lowering a @code{plain-file} yields a store
7598 item. This is achieved using the @code{lower-object} monadic procedure.
7600 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
7602 Return as a value in @var{%store-monad} the derivation or store item
7603 corresponding to @var{obj} for @var{system}, cross-compiling for
7604 @var{target} if @var{target} is true. @var{obj} must be an object that
7605 has an associated gexp compiler, such as a @code{<package>}.
7608 @node Invoking guix repl
7609 @section Invoking @command{guix repl}
7611 @cindex REPL, read-eval-print loop
7612 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
7613 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
7614 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
7615 command, @command{guix repl} guarantees that all the Guix modules and all its
7616 dependencies are available in the search path. You can use it this way:
7620 scheme@@(guile-user)> ,use (gnu packages base)
7621 scheme@@(guile-user)> coreutils
7622 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
7626 In addition, @command{guix repl} implements a simple machine-readable REPL
7627 protocol for use by @code{(guix inferior)}, a facility to interact with
7628 @dfn{inferiors}, separate processes running a potentially different revision
7631 The available options are as follows:
7634 @item --type=@var{type}
7635 @itemx -t @var{type}
7636 Start a REPL of the given @var{TYPE}, which can be one of the following:
7640 This is default, and it spawns a standard full-featured Guile REPL.
7642 Spawn a REPL that uses the machine-readable protocol. This is the protocol
7643 that the @code{(guix inferior)} module speaks.
7646 @item --listen=@var{endpoint}
7647 By default, @command{guix repl} reads from standard input and writes to
7648 standard output. When this option is passed, it will instead listen for
7649 connections on @var{endpoint}. Here are examples of valid options:
7652 @item --listen=tcp:37146
7653 Accept connections on localhost on port 37146.
7655 @item --listen=unix:/tmp/socket
7656 Accept connections on the Unix-domain socket @file{/tmp/socket}.
7660 @c *********************************************************************
7664 This section describes Guix command-line utilities. Some of them are
7665 primarily targeted at developers and users who write new package
7666 definitions, while others are more generally useful. They complement
7667 the Scheme programming interface of Guix in a convenient way.
7670 * Invoking guix build:: Building packages from the command line.
7671 * Invoking guix edit:: Editing package definitions.
7672 * Invoking guix download:: Downloading a file and printing its hash.
7673 * Invoking guix hash:: Computing the cryptographic hash of a file.
7674 * Invoking guix import:: Importing package definitions.
7675 * Invoking guix refresh:: Updating package definitions.
7676 * Invoking guix lint:: Finding errors in package definitions.
7677 * Invoking guix size:: Profiling disk usage.
7678 * Invoking guix graph:: Visualizing the graph of packages.
7679 * Invoking guix publish:: Sharing substitutes.
7680 * Invoking guix challenge:: Challenging substitute servers.
7681 * Invoking guix copy:: Copying to and from a remote store.
7682 * Invoking guix container:: Process isolation.
7683 * Invoking guix weather:: Assessing substitute availability.
7684 * Invoking guix processes:: Listing client processes.
7687 @node Invoking guix build
7688 @section Invoking @command{guix build}
7690 @cindex package building
7691 @cindex @command{guix build}
7692 The @command{guix build} command builds packages or derivations and
7693 their dependencies, and prints the resulting store paths. Note that it
7694 does not modify the user's profile---this is the job of the
7695 @command{guix package} command (@pxref{Invoking guix package}). Thus,
7696 it is mainly useful for distribution developers.
7698 The general syntax is:
7701 guix build @var{options} @var{package-or-derivation}@dots{}
7704 As an example, the following command builds the latest versions of Emacs
7705 and of Guile, displays their build logs, and finally displays the
7706 resulting directories:
7709 guix build emacs guile
7712 Similarly, the following command builds all the available packages:
7715 guix build --quiet --keep-going \
7716 `guix package -A | cut -f1,2 --output-delimiter=@@`
7719 @var{package-or-derivation} may be either the name of a package found in
7720 the software distribution such as @code{coreutils} or
7721 @code{coreutils@@8.20}, or a derivation such as
7722 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
7723 package with the corresponding name (and optionally version) is searched
7724 for among the GNU distribution modules (@pxref{Package Modules}).
7726 Alternatively, the @code{--expression} option may be used to specify a
7727 Scheme expression that evaluates to a package; this is useful when
7728 disambiguating among several same-named packages or package variants is
7731 There may be zero or more @var{options}. The available options are
7732 described in the subsections below.
7735 * Common Build Options:: Build options for most commands.
7736 * Package Transformation Options:: Creating variants of packages.
7737 * Additional Build Options:: Options specific to 'guix build'.
7738 * Debugging Build Failures:: Real life packaging experience.
7741 @node Common Build Options
7742 @subsection Common Build Options
7744 A number of options that control the build process are common to
7745 @command{guix build} and other commands that can spawn builds, such as
7746 @command{guix package} or @command{guix archive}. These are the
7751 @item --load-path=@var{directory}
7752 @itemx -L @var{directory}
7753 Add @var{directory} to the front of the package module search path
7754 (@pxref{Package Modules}).
7756 This allows users to define their own packages and make them visible to
7757 the command-line tools.
7761 Keep the build tree of failed builds. Thus, if a build fails, its build
7762 tree is kept under @file{/tmp}, in a directory whose name is shown at
7763 the end of the build log. This is useful when debugging build issues.
7764 @xref{Debugging Build Failures}, for tips and tricks on how to debug
7767 This option has no effect when connecting to a remote daemon with a
7768 @code{guix://} URI (@pxref{The Store, the @code{GUIX_DAEMON_SOCKET}
7773 Keep going when some of the derivations fail to build; return only once
7774 all the builds have either completed or failed.
7776 The default behavior is to stop as soon as one of the specified
7777 derivations has failed.
7781 Do not build the derivations.
7783 @anchor{fallback-option}
7785 When substituting a pre-built binary fails, fall back to building
7786 packages locally (@pxref{Substitution Failure}).
7788 @item --substitute-urls=@var{urls}
7789 @anchor{client-substitute-urls}
7790 Consider @var{urls} the whitespace-separated list of substitute source
7791 URLs, overriding the default list of URLs of @command{guix-daemon}
7792 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
7794 This means that substitutes may be downloaded from @var{urls}, provided
7795 they are signed by a key authorized by the system administrator
7796 (@pxref{Substitutes}).
7798 When @var{urls} is the empty string, substitutes are effectively
7801 @item --no-substitutes
7802 Do not use substitutes for build products. That is, always build things
7803 locally instead of allowing downloads of pre-built binaries
7804 (@pxref{Substitutes}).
7807 Do not ``graft'' packages. In practice, this means that package updates
7808 available as grafts are not applied. @xref{Security Updates}, for more
7809 information on grafts.
7811 @item --rounds=@var{n}
7812 Build each derivation @var{n} times in a row, and raise an error if
7813 consecutive build results are not bit-for-bit identical.
7815 This is a useful way to detect non-deterministic builds processes.
7816 Non-deterministic build processes are a problem because they make it
7817 practically impossible for users to @emph{verify} whether third-party
7818 binaries are genuine. @xref{Invoking guix challenge}, for more.
7820 Note that, currently, the differing build results are not kept around,
7821 so you will have to manually investigate in case of an error---e.g., by
7822 stashing one of the build results with @code{guix archive --export}
7823 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
7826 @item --no-build-hook
7827 Do not attempt to offload builds @i{via} the ``build hook'' of the daemon
7828 (@pxref{Daemon Offload Setup}). That is, always build things locally
7829 instead of offloading builds to remote machines.
7831 @item --max-silent-time=@var{seconds}
7832 When the build or substitution process remains silent for more than
7833 @var{seconds}, terminate it and report a build failure.
7835 By default, the daemon's setting is honored (@pxref{Invoking
7836 guix-daemon, @code{--max-silent-time}}).
7838 @item --timeout=@var{seconds}
7839 Likewise, when the build or substitution process lasts for more than
7840 @var{seconds}, terminate it and report a build failure.
7842 By default, the daemon's setting is honored (@pxref{Invoking
7843 guix-daemon, @code{--timeout}}).
7845 @c Note: This option is actually not part of %standard-build-options but
7846 @c most programs honor it.
7847 @cindex verbosity, of the command-line tools
7848 @cindex build logs, verbosity
7849 @item -v @var{level}
7850 @itemx --verbosity=@var{level}
7851 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
7852 output is produced, 1 is for quiet output, and 2 shows all the build log
7853 output on standard error.
7855 @item --cores=@var{n}
7857 Allow the use of up to @var{n} CPU cores for the build. The special
7858 value @code{0} means to use as many CPU cores as available.
7860 @item --max-jobs=@var{n}
7862 Allow at most @var{n} build jobs in parallel. @xref{Invoking
7863 guix-daemon, @code{--max-jobs}}, for details about this option and the
7864 equivalent @command{guix-daemon} option.
7866 @item --debug=@var{level}
7867 Produce debugging output coming from the build daemon. @var{level} must be an
7868 integer between 0 and 5; higher means more verbose output. Setting a level of
7869 4 or more may be helpful when debugging setup issues with the build daemon.
7873 Behind the scenes, @command{guix build} is essentially an interface to
7874 the @code{package-derivation} procedure of the @code{(guix packages)}
7875 module, and to the @code{build-derivations} procedure of the @code{(guix
7876 derivations)} module.
7878 In addition to options explicitly passed on the command line,
7879 @command{guix build} and other @command{guix} commands that support
7880 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
7882 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
7883 Users can define this variable to a list of command line options that
7884 will automatically be used by @command{guix build} and other
7885 @command{guix} commands that can perform builds, as in the example
7889 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
7892 These options are parsed independently, and the result is appended to
7893 the parsed command-line options.
7897 @node Package Transformation Options
7898 @subsection Package Transformation Options
7900 @cindex package variants
7901 Another set of command-line options supported by @command{guix build}
7902 and also @command{guix package} are @dfn{package transformation
7903 options}. These are options that make it possible to define @dfn{package
7904 variants}---for instance, packages built from different source code.
7905 This is a convenient way to create customized packages on the fly
7906 without having to type in the definitions of package variants
7907 (@pxref{Defining Packages}).
7911 @item --with-source=@var{source}
7912 @itemx --with-source=@var{package}=@var{source}
7913 @itemx --with-source=@var{package}@@@var{version}=@var{source}
7914 Use @var{source} as the source of @var{package}, and @var{version} as
7916 @var{source} must be a file name or a URL, as for @command{guix
7917 download} (@pxref{Invoking guix download}).
7919 When @var{package} is omitted,
7920 it is taken to be the package name specified on the
7921 command line that matches the base of @var{source}---e.g.,
7922 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
7923 package is @code{guile}.
7925 Likewise, when @var{version} is omitted, the version string is inferred from
7926 @var{source}; in the previous example, it is @code{2.0.10}.
7928 This option allows users to try out versions of packages other than the
7929 one provided by the distribution. The example below downloads
7930 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
7931 the @code{ed} package:
7934 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
7937 As a developer, @code{--with-source} makes it easy to test release
7941 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
7944 @dots{} or to build from a checkout in a pristine environment:
7947 $ git clone git://git.sv.gnu.org/guix.git
7948 $ guix build guix --with-source=guix@@1.0=./guix
7951 @item --with-input=@var{package}=@var{replacement}
7952 Replace dependency on @var{package} by a dependency on
7953 @var{replacement}. @var{package} must be a package name, and
7954 @var{replacement} must be a package specification such as @code{guile}
7955 or @code{guile@@1.8}.
7957 For instance, the following command builds Guix, but replaces its
7958 dependency on the current stable version of Guile with a dependency on
7959 the legacy version of Guile, @code{guile@@2.0}:
7962 guix build --with-input=guile=guile@@2.0 guix
7965 This is a recursive, deep replacement. So in this example, both
7966 @code{guix} and its dependency @code{guile-json} (which also depends on
7967 @code{guile}) get rebuilt against @code{guile@@2.0}.
7969 This is implemented using the @code{package-input-rewriting} Scheme
7970 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
7972 @item --with-graft=@var{package}=@var{replacement}
7973 This is similar to @code{--with-input} but with an important difference:
7974 instead of rebuilding the whole dependency chain, @var{replacement} is
7975 built and then @dfn{grafted} onto the binaries that were initially
7976 referring to @var{package}. @xref{Security Updates}, for more
7977 information on grafts.
7979 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
7980 and all its dependencies, replacing references to the version of GnuTLS
7981 they currently refer to:
7984 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
7987 This has the advantage of being much faster than rebuilding everything.
7988 But there is a caveat: it works if and only if @var{package} and
7989 @var{replacement} are strictly compatible---for example, if they provide
7990 a library, the application binary interface (ABI) of those libraries
7991 must be compatible. If @var{replacement} is somehow incompatible with
7992 @var{package}, then the resulting package may be unusable. Use with
7995 @item --with-git-url=@var{package}=@var{url}
7996 @cindex Git, using the latest commit
7997 @cindex latest commit, building
7998 Build @var{package} from the latest commit of the @code{master} branch of the
7999 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8002 For example, the following command builds the NumPy Python library against the
8003 latest commit of the master branch of Python itself:
8006 guix build python-numpy \
8007 --with-git-url=python=https://github.com/python/cpython
8010 This option can also be combined with @code{--with-branch} or
8011 @code{--with-commit} (see below).
8013 @cindex continuous integration
8014 Obviously, since it uses the latest commit of the given branch, the result of
8015 such a command varies over time. Nevertheless it is a convenient way to
8016 rebuild entire software stacks against the latest commit of one or more
8017 packages. This is particularly useful in the context of continuous
8020 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8021 consecutive accesses to the same repository. You may want to clean it up once
8022 in a while to save disk space.
8024 @item --with-branch=@var{package}=@var{branch}
8025 Build @var{package} from the latest commit of @var{branch}. If the
8026 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8027 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8028 repository URL is taken from that @code{source}. Otherwise you have to use
8029 @code{--with-git-url} to specify the URL of the Git repository.
8031 For instance, the following command builds @code{guile-sqlite3} from the
8032 latest commit of its @code{master} branch, and then builds @code{guix} (which
8033 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8034 specific @code{guile-sqlite3} build:
8037 guix build --with-branch=guile-sqlite3=master cuirass
8040 @item --with-commit=@var{package}=@var{commit}
8041 This is similar to @code{--with-branch}, except that it builds from
8042 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8043 Git commit SHA1 identifier.
8046 @node Additional Build Options
8047 @subsection Additional Build Options
8049 The command-line options presented below are specific to @command{guix
8056 Build quietly, without displaying the build log; this is equivalent to
8057 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8058 (or similar) and can always be retrieved using the @option{--log-file} option.
8060 @item --file=@var{file}
8061 @itemx -f @var{file}
8062 Build the package, derivation, or other file-like object that the code within
8063 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8065 As an example, @var{file} might contain a package definition like this
8066 (@pxref{Defining Packages}):
8069 @verbatiminclude package-hello.scm
8072 @item --expression=@var{expr}
8073 @itemx -e @var{expr}
8074 Build the package or derivation @var{expr} evaluates to.
8076 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8077 guile-1.8)}, which unambiguously designates this specific variant of
8078 version 1.8 of Guile.
8080 Alternatively, @var{expr} may be a G-expression, in which case it is used
8081 as a build program passed to @code{gexp->derivation}
8082 (@pxref{G-Expressions}).
8084 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8085 (@pxref{The Store Monad}). The procedure must return a derivation as a
8086 monadic value, which is then passed through @code{run-with-store}.
8090 Build the source derivations of the packages, rather than the packages
8093 For instance, @code{guix build -S gcc} returns something like
8094 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8097 The returned source tarball is the result of applying any patches and
8098 code snippets specified in the package @code{origin} (@pxref{Defining
8102 Fetch and return the source of @var{package-or-derivation} and all their
8103 dependencies, recursively. This is a handy way to obtain a local copy
8104 of all the source code needed to build @var{packages}, allowing you to
8105 eventually build them even without network access. It is an extension
8106 of the @code{--source} option and can accept one of the following
8107 optional argument values:
8111 This value causes the @code{--sources} option to behave in the same way
8112 as the @code{--source} option.
8115 Build the source derivations of all packages, including any source that
8116 might be listed as @code{inputs}. This is the default value.
8119 $ guix build --sources tzdata
8120 The following derivations will be built:
8121 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8122 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8126 Build the source derivations of all packages, as well of all transitive
8127 inputs to the packages. This can be used e.g.@: to
8128 prefetch package source for later offline building.
8131 $ guix build --sources=transitive tzdata
8132 The following derivations will be built:
8133 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8134 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8135 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8136 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8137 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8138 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8144 @item --system=@var{system}
8145 @itemx -s @var{system}
8146 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8147 the system type of the build host. The @command{guix build} command allows
8148 you to repeat this option several times, in which case it builds for all the
8149 specified systems; other commands ignore extraneous @option{-s} options.
8152 The @code{--system} flag is for @emph{native} compilation and must not
8153 be confused with cross-compilation. See @code{--target} below for
8154 information on cross-compilation.
8157 An example use of this is on Linux-based systems, which can emulate
8158 different personalities. For instance, passing
8159 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8160 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8161 to build packages in a complete 32-bit environment.
8164 Building for an @code{armhf-linux} system is unconditionally enabled on
8165 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8166 allow for this functionality, notably the ThunderX.
8169 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8170 is enabled (@pxref{Virtualization Services,
8171 @code{qemu-binfmt-service-type}}), you can build for any system for
8172 which a QEMU @code{binfmt_misc} handler is installed.
8174 Builds for a system other than that of the machine you are using can
8175 also be offloaded to a remote machine of the right architecture.
8176 @xref{Daemon Offload Setup}, for more information on offloading.
8178 @item --target=@var{triplet}
8179 @cindex cross-compilation
8180 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8181 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8182 configuration triplets,, autoconf, Autoconf}).
8184 @anchor{build-check}
8186 @cindex determinism, checking
8187 @cindex reproducibility, checking
8188 Rebuild @var{package-or-derivation}, which are already available in the
8189 store, and raise an error if the build results are not bit-for-bit
8192 This mechanism allows you to check whether previously installed
8193 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8194 of a package is deterministic. @xref{Invoking guix challenge}, for more
8195 background information and tools.
8197 When used in conjunction with @option{--keep-failed}, the differing
8198 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8199 This makes it easy to look for differences between the two results.
8202 @cindex repairing store items
8203 @cindex corruption, recovering from
8204 Attempt to repair the specified store items, if they are corrupt, by
8205 re-downloading or rebuilding them.
8207 This operation is not atomic and thus restricted to @code{root}.
8211 Return the derivation paths, not the output paths, of the given
8214 @item --root=@var{file}
8215 @itemx -r @var{file}
8216 @cindex GC roots, adding
8217 @cindex garbage collector roots, adding
8218 Make @var{file} a symlink to the result, and register it as a garbage
8221 Consequently, the results of this @command{guix build} invocation are
8222 protected from garbage collection until @var{file} is removed. When
8223 that option is omitted, build results are eligible for garbage
8224 collection as soon as the build completes. @xref{Invoking guix gc}, for
8228 @cindex build logs, access
8229 Return the build log file names or URLs for the given
8230 @var{package-or-derivation}, or raise an error if build logs are
8233 This works regardless of how packages or derivations are specified. For
8234 instance, the following invocations are equivalent:
8237 guix build --log-file `guix build -d guile`
8238 guix build --log-file `guix build guile`
8239 guix build --log-file guile
8240 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8243 If a log is unavailable locally, and unless @code{--no-substitutes} is
8244 passed, the command looks for a corresponding log on one of the
8245 substitute servers (as specified with @code{--substitute-urls}.)
8247 So for instance, imagine you want to see the build log of GDB on MIPS,
8248 but you are actually on an @code{x86_64} machine:
8251 $ guix build --log-file gdb -s mips64el-linux
8252 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8255 You can freely access a huge library of build logs!
8258 @node Debugging Build Failures
8259 @subsection Debugging Build Failures
8261 @cindex build failures, debugging
8262 When defining a new package (@pxref{Defining Packages}), you will
8263 probably find yourself spending some time debugging and tweaking the
8264 build until it succeeds. To do that, you need to operate the build
8265 commands yourself in an environment as close as possible to the one the
8268 To that end, the first thing to do is to use the @option{--keep-failed}
8269 or @option{-K} option of @command{guix build}, which will keep the
8270 failed build tree in @file{/tmp} or whatever directory you specified as
8271 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8273 From there on, you can @command{cd} to the failed build tree and source
8274 the @file{environment-variables} file, which contains all the
8275 environment variable definitions that were in place when the build
8276 failed. So let's say you're debugging a build failure in package
8277 @code{foo}; a typical session would look like this:
8281 @dots{} @i{build fails}
8282 $ cd /tmp/guix-build-foo.drv-0
8283 $ source ./environment-variables
8287 Now, you can invoke commands as if you were the daemon (almost) and
8288 troubleshoot your build process.
8290 Sometimes it happens that, for example, a package's tests pass when you
8291 run them manually but they fail when the daemon runs them. This can
8292 happen because the daemon runs builds in containers where, unlike in our
8293 environment above, network access is missing, @file{/bin/sh} does not
8294 exist, etc. (@pxref{Build Environment Setup}).
8296 In such cases, you may need to run inspect the build process from within
8297 a container similar to the one the build daemon creates:
8302 $ cd /tmp/guix-build-foo.drv-0
8303 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8304 [env]# source ./environment-variables
8308 Here, @command{guix environment -C} creates a container and spawns a new
8309 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8310 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8311 the container, which would may find handy while debugging. The
8312 @option{--no-grafts} option makes sure we get the exact same
8313 environment, with ungrafted packages (@pxref{Security Updates}, for more
8316 To get closer to a container like that used by the build daemon, we can
8317 remove @file{/bin/sh}:
8323 (Don't worry, this is harmless: this is all happening in the throw-away
8324 container created by @command{guix environment}.)
8326 The @command{strace} command is probably not in the search path, but we
8330 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8333 In this way, not only you will have reproduced the environment variables
8334 the daemon uses, you will also be running the build process in a container
8335 similar to the one the daemon uses.
8338 @node Invoking guix edit
8339 @section Invoking @command{guix edit}
8341 @cindex @command{guix edit}
8342 @cindex package definition, editing
8343 So many packages, so many source files! The @command{guix edit} command
8344 facilitates the life of users and packagers by pointing their editor at
8345 the source file containing the definition of the specified packages.
8349 guix edit gcc@@4.9 vim
8353 launches the program specified in the @code{VISUAL} or in the
8354 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8357 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8358 have created your own packages on @code{GUIX_PACKAGE_PATH}
8359 (@pxref{Package Modules}), you will be able to edit the package
8360 recipes. In other cases, you will be able to examine the read-only recipes
8361 for packages currently in the store.
8364 @node Invoking guix download
8365 @section Invoking @command{guix download}
8367 @cindex @command{guix download}
8368 @cindex downloading package sources
8369 When writing a package definition, developers typically need to download
8370 a source tarball, compute its SHA256 hash, and write that
8371 hash in the package definition (@pxref{Defining Packages}). The
8372 @command{guix download} tool helps with this task: it downloads a file
8373 from the given URI, adds it to the store, and prints both its file name
8374 in the store and its SHA256 hash.
8376 The fact that the downloaded file is added to the store saves bandwidth:
8377 when the developer eventually tries to build the newly defined package
8378 with @command{guix build}, the source tarball will not have to be
8379 downloaded again because it is already in the store. It is also a
8380 convenient way to temporarily stash files, which may be deleted
8381 eventually (@pxref{Invoking guix gc}).
8383 The @command{guix download} command supports the same URIs as used in
8384 package definitions. In particular, it supports @code{mirror://} URIs.
8385 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8386 Guile bindings for GnuTLS are available in the user's environment; when
8387 they are not available, an error is raised. @xref{Guile Preparations,
8388 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8389 GnuTLS-Guile}, for more information.
8391 @command{guix download} verifies HTTPS server certificates by loading
8392 the certificates of X.509 authorities from the directory pointed to by
8393 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8394 Certificates}), unless @option{--no-check-certificate} is used.
8396 The following options are available:
8399 @item --format=@var{fmt}
8401 Write the hash in the format specified by @var{fmt}. For more
8402 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8404 @item --no-check-certificate
8405 Do not validate the X.509 certificates of HTTPS servers.
8407 When using this option, you have @emph{absolutely no guarantee} that you
8408 are communicating with the authentic server responsible for the given
8409 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8411 @item --output=@var{file}
8412 @itemx -o @var{file}
8413 Save the downloaded file to @var{file} instead of adding it to the
8417 @node Invoking guix hash
8418 @section Invoking @command{guix hash}
8420 @cindex @command{guix hash}
8421 The @command{guix hash} command computes the SHA256 hash of a file.
8422 It is primarily a convenience tool for anyone contributing to the
8423 distribution: it computes the cryptographic hash of a file, which can be
8424 used in the definition of a package (@pxref{Defining Packages}).
8426 The general syntax is:
8429 guix hash @var{option} @var{file}
8432 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8433 hash of data read from standard input. @command{guix hash} has the
8438 @item --format=@var{fmt}
8440 Write the hash in the format specified by @var{fmt}.
8442 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8443 (@code{hex} and @code{hexadecimal} can be used as well).
8445 If the @option{--format} option is not specified, @command{guix hash}
8446 will output the hash in @code{nix-base32}. This representation is used
8447 in the definitions of packages.
8451 Compute the hash on @var{file} recursively.
8453 In this case, the hash is computed on an archive containing @var{file},
8454 including its children if it is a directory. Some of the metadata of
8455 @var{file} is part of the archive; for instance, when @var{file} is a
8456 regular file, the hash is different depending on whether @var{file} is
8457 executable or not. Metadata such as time stamps has no impact on the
8458 hash (@pxref{Invoking guix archive}).
8459 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8464 When combined with @option{--recursive}, exclude version control system
8465 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8468 As an example, here is how you would compute the hash of a Git checkout,
8469 which is useful when using the @code{git-fetch} method (@pxref{origin
8473 $ git clone http://example.org/foo.git
8479 @node Invoking guix import
8480 @section Invoking @command{guix import}
8482 @cindex importing packages
8483 @cindex package import
8484 @cindex package conversion
8485 @cindex Invoking @command{guix import}
8486 The @command{guix import} command is useful for people who would like to
8487 add a package to the distribution with as little work as
8488 possible---a legitimate demand. The command knows of a few
8489 repositories from which it can ``import'' package metadata. The result
8490 is a package definition, or a template thereof, in the format we know
8491 (@pxref{Defining Packages}).
8493 The general syntax is:
8496 guix import @var{importer} @var{options}@dots{}
8499 @var{importer} specifies the source from which to import package
8500 metadata, and @var{options} specifies a package identifier and other
8501 options specific to @var{importer}. Currently, the available
8506 Import metadata for the given GNU package. This provides a template
8507 for the latest version of that GNU package, including the hash of its
8508 source tarball, and its canonical synopsis and description.
8510 Additional information such as the package dependencies and its
8511 license needs to be figured out manually.
8513 For example, the following command returns a package definition for
8517 guix import gnu hello
8520 Specific command-line options are:
8523 @item --key-download=@var{policy}
8524 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
8525 keys when verifying the package signature. @xref{Invoking guix
8526 refresh, @code{--key-download}}.
8531 Import metadata from the @uref{https://pypi.python.org/, Python Package
8532 Index}. Information is taken from the JSON-formatted description
8533 available at @code{pypi.python.org} and usually includes all the relevant
8534 information, including package dependencies. For maximum efficiency, it
8535 is recommended to install the @command{unzip} utility, so that the
8536 importer can unzip Python wheels and gather data from them.
8538 The command below imports metadata for the @code{itsdangerous} Python
8542 guix import pypi itsdangerous
8548 Traverse the dependency graph of the given upstream package recursively
8549 and generate package expressions for all those packages that are not yet
8555 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
8556 is taken from the JSON-formatted description available at
8557 @code{rubygems.org} and includes most relevant information, including
8558 runtime dependencies. There are some caveats, however. The metadata
8559 doesn't distinguish between synopses and descriptions, so the same string
8560 is used for both fields. Additionally, the details of non-Ruby
8561 dependencies required to build native extensions is unavailable and left
8562 as an exercise to the packager.
8564 The command below imports metadata for the @code{rails} Ruby package:
8567 guix import gem rails
8573 Traverse the dependency graph of the given upstream package recursively
8574 and generate package expressions for all those packages that are not yet
8580 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
8581 Information is taken from the JSON-formatted metadata provided through
8582 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
8583 relevant information, such as module dependencies. License information
8584 should be checked closely. If Perl is available in the store, then the
8585 @code{corelist} utility will be used to filter core modules out of the
8586 list of dependencies.
8588 The command command below imports metadata for the @code{Acme::Boolean}
8592 guix import cpan Acme::Boolean
8597 @cindex Bioconductor
8598 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
8599 central repository for the @uref{https://r-project.org, GNU@tie{}R
8600 statistical and graphical environment}.
8602 Information is extracted from the @code{DESCRIPTION} file of the package.
8604 The command command below imports metadata for the @code{Cairo}
8608 guix import cran Cairo
8611 When @code{--recursive} is added, the importer will traverse the
8612 dependency graph of the given upstream package recursively and generate
8613 package expressions for all those packages that are not yet in Guix.
8615 When @code{--archive=bioconductor} is added, metadata is imported from
8616 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
8617 packages for for the analysis and comprehension of high-throughput
8618 genomic data in bioinformatics.
8620 Information is extracted from the @code{DESCRIPTION} file of a package
8621 published on the web interface of the Bioconductor SVN repository.
8623 The command below imports metadata for the @code{GenomicRanges}
8627 guix import cran --archive=bioconductor GenomicRanges
8633 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
8634 comprehensive TeX archive network for TeX packages that are part of the
8635 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
8637 Information about the package is obtained through the XML API provided
8638 by CTAN, while the source code is downloaded from the SVN repository of
8639 the Tex Live project. This is done because the CTAN does not keep
8642 The command command below imports metadata for the @code{fontspec}
8646 guix import texlive fontspec
8649 When @code{--archive=DIRECTORY} is added, the source code is downloaded
8650 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
8651 tree in the TeX Live SVN repository, but from the specified sibling
8652 directory under the same root.
8654 The command below imports metadata for the @code{ifxetex} package from
8655 CTAN while fetching the sources from the directory
8656 @file{texmf/source/generic}:
8659 guix import texlive --archive=generic ifxetex
8663 @cindex JSON, import
8664 Import package metadata from a local JSON file. Consider the following
8665 example package definition in JSON format:
8671 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
8672 "build-system": "gnu",
8673 "home-page": "https://www.gnu.org/software/hello/",
8674 "synopsis": "Hello, GNU world: An example GNU package",
8675 "description": "GNU Hello prints a greeting.",
8676 "license": "GPL-3.0+",
8677 "native-inputs": ["gcc@@6"]
8681 The field names are the same as for the @code{<package>} record
8682 (@xref{Defining Packages}). References to other packages are provided
8683 as JSON lists of quoted package specification strings such as
8684 @code{guile} or @code{guile@@2.0}.
8686 The importer also supports a more explicit source definition using the
8687 common fields for @code{<origin>} records:
8693 "method": "url-fetch",
8694 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
8696 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
8703 The command below reads metadata from the JSON file @code{hello.json}
8704 and outputs a package expression:
8707 guix import json hello.json
8711 Import metadata from a local copy of the source of the
8712 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
8713 relies on the @command{nix-instantiate} command of
8714 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
8715 typically written in a mixture of Nix-language and Bash code. This
8716 command only imports the high-level package structure that is written in
8717 the Nix language. It normally includes all the basic fields of a
8720 When importing a GNU package, the synopsis and descriptions are replaced
8721 by their canonical upstream variant.
8723 Usually, you will first need to do:
8726 export NIX_REMOTE=daemon
8730 so that @command{nix-instantiate} does not try to open the Nix database.
8732 As an example, the command below imports the package definition of
8733 LibreOffice (more precisely, it imports the definition of the package
8734 bound to the @code{libreoffice} top-level attribute):
8737 guix import nix ~/path/to/nixpkgs libreoffice
8742 Import metadata from the Haskell community's central package archive
8743 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
8744 Cabal files and includes all the relevant information, including package
8747 Specific command-line options are:
8752 Read a Cabal file from standard input.
8753 @item --no-test-dependencies
8755 Do not include dependencies required only by the test suites.
8756 @item --cabal-environment=@var{alist}
8757 @itemx -e @var{alist}
8758 @var{alist} is a Scheme alist defining the environment in which the
8759 Cabal conditionals are evaluated. The accepted keys are: @code{os},
8760 @code{arch}, @code{impl} and a string representing the name of a flag.
8761 The value associated with a flag has to be either the symbol
8762 @code{true} or @code{false}. The value associated with other keys
8763 has to conform to the Cabal file format definition. The default value
8764 associated with the keys @code{os}, @code{arch} and @code{impl} is
8765 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
8768 Traverse the dependency graph of the given upstream package recursively
8769 and generate package expressions for all those packages that are not yet
8773 The command below imports metadata for the latest version of the
8774 @code{HTTP} Haskell package without including test dependencies and
8775 specifying the value of the flag @samp{network-uri} as @code{false}:
8778 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
8781 A specific package version may optionally be specified by following the
8782 package name by an at-sign and a version number as in the following example:
8785 guix import hackage mtl@@2.1.3.1
8790 The @code{stackage} importer is a wrapper around the @code{hackage} one.
8791 It takes a package name, looks up the package version included in a
8792 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
8793 release and uses the @code{hackage} importer to retrieve its metadata.
8794 Note that it is up to you to select an LTS release compatible with the
8795 GHC compiler used by Guix.
8797 Specific command-line options are:
8800 @item --no-test-dependencies
8802 Do not include dependencies required only by the test suites.
8803 @item --lts-version=@var{version}
8804 @itemx -l @var{version}
8805 @var{version} is the desired LTS release version. If omitted the latest
8809 Traverse the dependency graph of the given upstream package recursively
8810 and generate package expressions for all those packages that are not yet
8814 The command below imports metadata for the @code{HTTP} Haskell package
8815 included in the LTS Stackage release version 7.18:
8818 guix import stackage --lts-version=7.18 HTTP
8823 Import metadata from an Emacs Lisp Package Archive (ELPA) package
8824 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
8826 Specific command-line options are:
8829 @item --archive=@var{repo}
8830 @itemx -a @var{repo}
8831 @var{repo} identifies the archive repository from which to retrieve the
8832 information. Currently the supported repositories and their identifiers
8836 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
8837 identifier. This is the default.
8839 Packages from @code{elpa.gnu.org} are signed with one of the keys
8840 contained in the GnuPG keyring at
8841 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
8842 @code{emacs} package (@pxref{Package Installation, ELPA package
8843 signatures,, emacs, The GNU Emacs Manual}).
8846 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
8847 @code{melpa-stable} identifier.
8850 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
8856 Traverse the dependency graph of the given upstream package recursively
8857 and generate package expressions for all those packages that are not yet
8863 Import metadata from the crates.io Rust package repository
8864 @uref{https://crates.io, crates.io}.
8869 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
8870 repository used by the OCaml community.
8873 The structure of the @command{guix import} code is modular. It would be
8874 useful to have more importers for other package formats, and your help
8875 is welcome here (@pxref{Contributing}).
8877 @node Invoking guix refresh
8878 @section Invoking @command{guix refresh}
8880 @cindex @command {guix refresh}
8881 The primary audience of the @command{guix refresh} command is developers
8882 of the GNU software distribution. By default, it reports any packages
8883 provided by the distribution that are outdated compared to the latest
8884 upstream version, like this:
8888 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
8889 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
8892 Alternately, one can specify packages to consider, in which case a
8893 warning is emitted for packages that lack an updater:
8896 $ guix refresh coreutils guile guile-ssh
8897 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
8898 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
8901 @command{guix refresh} browses the upstream repository of each package and determines
8902 the highest version number of the releases therein. The command
8903 knows how to update specific types of packages: GNU packages, ELPA
8904 packages, etc.---see the documentation for @option{--type} below. There
8905 are many packages, though, for which it lacks a method to determine
8906 whether a new upstream release is available. However, the mechanism is
8907 extensible, so feel free to get in touch with us to add a new method!
8912 Consider the packages specified, and all the packages upon which they depend.
8915 $ guix refresh --recursive coreutils
8916 gnu/packages/acl.scm:35:2: warning: no updater for acl
8917 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
8918 gnu/packages/xml.scm:68:2: warning: no updater for expat
8919 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
8925 Sometimes the upstream name differs from the package name used in Guix,
8926 and @command{guix refresh} needs a little help. Most updaters honor the
8927 @code{upstream-name} property in package definitions, which can be used
8931 (define-public network-manager
8933 (name "network-manager")
8935 (properties '((upstream-name . "NetworkManager")))))
8938 When passed @code{--update}, it modifies distribution source files to
8939 update the version numbers and source tarball hashes of those package
8940 recipes (@pxref{Defining Packages}). This is achieved by downloading
8941 each package's latest source tarball and its associated OpenPGP
8942 signature, authenticating the downloaded tarball against its signature
8943 using @command{gpg}, and finally computing its hash. When the public
8944 key used to sign the tarball is missing from the user's keyring, an
8945 attempt is made to automatically retrieve it from a public key server;
8946 when this is successful, the key is added to the user's keyring; otherwise,
8947 @command{guix refresh} reports an error.
8949 The following options are supported:
8953 @item --expression=@var{expr}
8954 @itemx -e @var{expr}
8955 Consider the package @var{expr} evaluates to.
8957 This is useful to precisely refer to a package, as in this example:
8960 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
8963 This command lists the dependents of the ``final'' libc (essentially all
8968 Update distribution source files (package recipes) in place. This is
8969 usually run from a checkout of the Guix source tree (@pxref{Running
8970 Guix Before It Is Installed}):
8973 $ ./pre-inst-env guix refresh -s non-core -u
8976 @xref{Defining Packages}, for more information on package definitions.
8978 @item --select=[@var{subset}]
8979 @itemx -s @var{subset}
8980 Select all the packages in @var{subset}, one of @code{core} or
8983 The @code{core} subset refers to all the packages at the core of the
8984 distribution---i.e., packages that are used to build ``everything
8985 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
8986 changing one of these packages in the distribution entails a rebuild of
8987 all the others. Thus, such updates are an inconvenience to users in
8988 terms of build time or bandwidth used to achieve the upgrade.
8990 The @code{non-core} subset refers to the remaining packages. It is
8991 typically useful in cases where an update of the core packages would be
8994 @item --manifest=@var{file}
8995 @itemx -m @var{file}
8996 Select all the packages from the manifest in @var{file}. This is useful to
8997 check if any packages of the user manifest can be updated.
8999 @item --type=@var{updater}
9000 @itemx -t @var{updater}
9001 Select only packages handled by @var{updater} (may be a comma-separated
9002 list of updaters). Currently, @var{updater} may be one of:
9006 the updater for GNU packages;
9008 the updater for GNOME packages;
9010 the updater for KDE packages;
9012 the updater for X.org packages;
9014 the updater for packages hosted on kernel.org;
9016 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9018 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9020 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9022 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9024 the updater for @uref{https://pypi.python.org, PyPI} packages.
9026 the updater for @uref{https://rubygems.org, RubyGems} packages.
9028 the updater for @uref{https://github.com, GitHub} packages.
9030 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9032 the updater for @uref{https://www.stackage.org, Stackage} packages.
9034 the updater for @uref{https://crates.io, Crates} packages.
9036 the updater for @uref{https://launchpad.net, Launchpad} packages.
9039 For instance, the following command only checks for updates of Emacs
9040 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9043 $ guix refresh --type=elpa,cran
9044 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9045 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9050 In addition, @command{guix refresh} can be passed one or more package
9051 names, as in this example:
9054 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9058 The command above specifically updates the @code{emacs} and
9059 @code{idutils} packages. The @code{--select} option would have no
9060 effect in this case.
9062 When considering whether to upgrade a package, it is sometimes
9063 convenient to know which packages would be affected by the upgrade and
9064 should be checked for compatibility. For this the following option may
9065 be used when passing @command{guix refresh} one or more package names:
9069 @item --list-updaters
9071 List available updaters and exit (see @option{--type} above.)
9073 For each updater, display the fraction of packages it covers; at the
9074 end, display the fraction of packages covered by all these updaters.
9076 @item --list-dependent
9078 List top-level dependent packages that would need to be rebuilt as a
9079 result of upgrading one or more packages.
9081 @xref{Invoking guix graph, the @code{reverse-package} type of
9082 @command{guix graph}}, for information on how to visualize the list of
9083 dependents of a package.
9087 Be aware that the @code{--list-dependent} option only
9088 @emph{approximates} the rebuilds that would be required as a result of
9089 an upgrade. More rebuilds might be required under some circumstances.
9092 $ guix refresh --list-dependent flex
9093 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9094 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9097 The command above lists a set of packages that could be built to check
9098 for compatibility with an upgraded @code{flex} package.
9102 @item --list-transitive
9103 List all the packages which one or more packages depend upon.
9106 $ guix refresh --list-transitive flex
9107 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9108 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{}
9113 The command above lists a set of packages which, when changed, would cause
9114 @code{flex} to be rebuilt.
9116 The following options can be used to customize GnuPG operation:
9120 @item --gpg=@var{command}
9121 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9122 for in @code{$PATH}.
9124 @item --keyring=@var{file}
9125 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9126 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9127 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9128 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9129 information on a tool to manipulate keybox files).
9131 When this option is omitted, @command{guix refresh} uses
9132 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9133 signing keys. OpenPGP signatures are checked against keys from this keyring;
9134 missing keys are downloaded to this keyring as well (see
9135 @option{--key-download} below.)
9137 You can export keys from your default GPG keyring into a keybox file using
9138 commands like this one:
9141 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9144 Likewise, you can fetch keys to a specific keybox file like this:
9147 gpg --no-default-keyring --keyring mykeyring.kbx \
9148 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9151 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9152 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9154 @item --key-download=@var{policy}
9155 Handle missing OpenPGP keys according to @var{policy}, which may be one
9160 Always download missing OpenPGP keys from the key server, and add them
9161 to the user's GnuPG keyring.
9164 Never try to download missing OpenPGP keys. Instead just bail out.
9167 When a package signed with an unknown OpenPGP key is encountered, ask
9168 the user whether to download it or not. This is the default behavior.
9171 @item --key-server=@var{host}
9172 Use @var{host} as the OpenPGP key server when importing a public key.
9176 The @code{github} updater uses the
9177 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9178 releases. When used repeatedly e.g.@: when refreshing all packages,
9179 GitHub will eventually refuse to answer any further API requests. By
9180 default 60 API requests per hour are allowed, and a full refresh on all
9181 GitHub packages in Guix requires more than this. Authentication with
9182 GitHub through the use of an API token alleviates these limits. To use
9183 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9184 token procured from @uref{https://github.com/settings/tokens} or
9188 @node Invoking guix lint
9189 @section Invoking @command{guix lint}
9191 @cindex @command{guix lint}
9192 @cindex package, checking for errors
9193 The @command{guix lint} command is meant to help package developers avoid
9194 common errors and use a consistent style. It runs a number of checks on
9195 a given set of packages in order to find common mistakes in their
9196 definitions. Available @dfn{checkers} include (see
9197 @code{--list-checkers} for a complete list):
9202 Validate certain typographical and stylistic rules about package
9203 descriptions and synopses.
9205 @item inputs-should-be-native
9206 Identify inputs that should most likely be native inputs.
9212 @itemx source-file-name
9213 Probe @code{home-page} and @code{source} URLs and report those that are
9214 invalid. Suggest a @code{mirror://} URL when applicable. If the
9215 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9216 URL. Check that the source file name is meaningful, e.g.@: is not just a
9217 version number or ``git-checkout'', without a declared @code{file-name}
9218 (@pxref{origin Reference}).
9220 @item source-unstable-tarball
9221 Parse the @code{source} URL to determine if a tarball from GitHub is
9222 autogenerated or if it is a release tarball. Unfortunately GitHub's
9223 autogenerated tarballs are sometimes regenerated.
9226 @cindex security vulnerabilities
9227 @cindex CVE, Common Vulnerabilities and Exposures
9228 Report known vulnerabilities found in the Common Vulnerabilities and
9229 Exposures (CVE) databases of the current and past year
9230 @uref{https://nvd.nist.gov/download.cfm#CVE_FEED, published by the US
9233 To view information about a particular vulnerability, visit pages such as:
9237 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9239 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9243 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9244 @code{CVE-2015-7554}.
9246 Package developers can specify in package recipes the
9247 @uref{https://nvd.nist.gov/cpe.cfm,Common Platform Enumeration (CPE)}
9248 name and version of the package when they differ from the name or version
9249 that Guix uses, as in this example:
9255 ;; CPE calls this package "grub2".
9256 (properties '((cpe-name . "grub2")
9257 (cpe-version . "2.3")))
9260 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9261 Some entries in the CVE database do not specify which version of a
9262 package they apply to, and would thus ``stick around'' forever. Package
9263 developers who found CVE alerts and verified they can be ignored can
9264 declare them as in this example:
9270 ;; These CVEs no longer apply and can be safely ignored.
9271 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9274 "CVE-2011-5244")))))
9278 Warn about obvious source code formatting issues: trailing white space,
9279 use of tabulations, etc.
9282 The general syntax is:
9285 guix lint @var{options} @var{package}@dots{}
9288 If no package is given on the command line, then all packages are checked.
9289 The @var{options} may be zero or more of the following:
9292 @item --list-checkers
9294 List and describe all the available checkers that will be run on packages
9299 Only enable the checkers specified in a comma-separated list using the
9300 names returned by @code{--list-checkers}.
9304 @node Invoking guix size
9305 @section Invoking @command{guix size}
9308 @cindex package size
9310 @cindex @command{guix size}
9311 The @command{guix size} command helps package developers profile the
9312 disk usage of packages. It is easy to overlook the impact of an
9313 additional dependency added to a package, or the impact of using a
9314 single output for a package that could easily be split (@pxref{Packages
9315 with Multiple Outputs}). Such are the typical issues that
9316 @command{guix size} can highlight.
9318 The command can be passed one or more package specifications
9319 such as @code{gcc@@4.8}
9320 or @code{guile:debug}, or a file name in the store. Consider this
9324 $ guix size coreutils
9325 store item total self
9326 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9327 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9328 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9329 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9330 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9331 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9332 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9333 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9338 The store items listed here constitute the @dfn{transitive closure} of
9339 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9340 would be returned by:
9343 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9346 Here the output shows three columns next to store items. The first column,
9347 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9348 the store item---that is, its own size plus the size of all its
9349 dependencies. The next column, labeled ``self'', shows the size of the
9350 item itself. The last column shows the ratio of the size of the item
9351 itself to the space occupied by all the items listed here.
9353 In this example, we see that the closure of Coreutils weighs in at
9354 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9355 libraries. (That libc and GCC's libraries represent a large fraction of
9356 the closure is not a problem @i{per se} because they are always available
9357 on the system anyway.)
9359 When the package(s) passed to @command{guix size} are available in the
9360 store@footnote{More precisely, @command{guix size} looks for the
9361 @emph{ungrafted} variant of the given package(s), as returned by
9362 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9363 for information on grafts.}, @command{guix size} queries the daemon to determine its
9364 dependencies, and measures its size in the store, similar to @command{du
9365 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9368 When the given packages are @emph{not} in the store, @command{guix size}
9369 reports information based on the available substitutes
9370 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9371 store items that are not even on disk, only available remotely.
9373 You can also specify several package names:
9376 $ guix size coreutils grep sed bash
9377 store item total self
9378 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9379 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9380 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9381 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9387 In this example we see that the combination of the four packages takes
9388 102.3@tie{}MiB in total, which is much less than the sum of each closure
9389 since they have a lot of dependencies in common.
9391 The available options are:
9395 @item --substitute-urls=@var{urls}
9396 Use substitute information from @var{urls}.
9397 @xref{client-substitute-urls, the same option for @code{guix build}}.
9399 @item --sort=@var{key}
9400 Sort lines according to @var{key}, one of the following options:
9404 the size of each item (the default);
9406 the total size of the item's closure.
9409 @item --map-file=@var{file}
9410 Write a graphical map of disk usage in PNG format to @var{file}.
9412 For the example above, the map looks like this:
9414 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
9415 produced by @command{guix size}}
9417 This option requires that
9418 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
9419 installed and visible in Guile's module search path. When that is not
9420 the case, @command{guix size} fails as it tries to load it.
9422 @item --system=@var{system}
9423 @itemx -s @var{system}
9424 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
9428 @node Invoking guix graph
9429 @section Invoking @command{guix graph}
9432 @cindex @command{guix graph}
9433 @cindex package dependencies
9434 Packages and their dependencies form a @dfn{graph}, specifically a
9435 directed acyclic graph (DAG). It can quickly become difficult to have a
9436 mental model of the package DAG, so the @command{guix graph} command
9437 provides a visual representation of the DAG. By default,
9438 @command{guix graph} emits a DAG representation in the input format of
9439 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
9440 directly to the @command{dot} command of Graphviz. It can also emit an
9441 HTML page with embedded JavaScript code to display a ``chord diagram''
9442 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
9443 emit Cypher queries to construct a graph in a graph database supporting
9444 the @uref{https://www.opencypher.org/, openCypher} query language.
9445 The general syntax is:
9448 guix graph @var{options} @var{package}@dots{}
9451 For example, the following command generates a PDF file representing the
9452 package DAG for the GNU@tie{}Core Utilities, showing its build-time
9456 guix graph coreutils | dot -Tpdf > dag.pdf
9459 The output looks like this:
9461 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
9463 Nice little graph, no?
9465 But there is more than one graph! The one above is concise: it is the
9466 graph of package objects, omitting implicit inputs such as GCC, libc,
9467 grep, etc. It is often useful to have such a concise graph, but
9468 sometimes one may want to see more details. @command{guix graph} supports
9469 several types of graphs, allowing you to choose the level of detail:
9473 This is the default type used in the example above. It shows the DAG of
9474 package objects, excluding implicit dependencies. It is concise, but
9475 filters out many details.
9477 @item reverse-package
9478 This shows the @emph{reverse} DAG of packages. For example:
9481 guix graph --type=reverse-package ocaml
9484 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
9485 you are also interested in cases where OCaml is an implicit dependency, see
9486 @code{reverse-bag} below.)
9488 Note that for core packages this can yield huge graphs. If all you want
9489 is to know the number of packages that depend on a given package, use
9490 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
9491 @option{--list-dependent}}).
9494 This is the package DAG, @emph{including} implicit inputs.
9496 For instance, the following command:
9499 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
9502 ...@: yields this bigger graph:
9504 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
9506 At the bottom of the graph, we see all the implicit inputs of
9507 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
9509 Now, note that the dependencies of these implicit inputs---that is, the
9510 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
9511 here, for conciseness.
9514 Similar to @code{bag-emerged}, but this time including all the bootstrap
9517 @item bag-with-origins
9518 Similar to @code{bag}, but also showing origins and their dependencies.
9521 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
9522 it also takes implicit dependencies into account. For example:
9525 guix graph -t reverse-bag dune
9529 ...@: yields the graph of all packages that depend on Dune, directly or
9530 indirectly. Since Dune is an @emph{implicit} dependency of many packages
9531 @i{via} @code{dune-build-system}, this shows a large number of packages,
9532 whereas @code{reverse-package} would show very few if any.
9535 This is the most detailed representation: It shows the DAG of
9536 derivations (@pxref{Derivations}) and plain store items. Compared to
9537 the above representation, many additional nodes are visible, including
9538 build scripts, patches, Guile modules, etc.
9540 For this type of graph, it is also possible to pass a @file{.drv} file
9541 name instead of a package name, as in:
9544 guix graph -t derivation `guix system build -d my-config.scm`
9548 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
9549 For example, the following command shows the graph for the package
9550 module that defines the @code{guile} package:
9553 guix graph -t module guile | dot -Tpdf > module-graph.pdf
9557 All the types above correspond to @emph{build-time dependencies}. The
9558 following graph type represents the @emph{run-time dependencies}:
9562 This is the graph of @dfn{references} of a package output, as returned
9563 by @command{guix gc --references} (@pxref{Invoking guix gc}).
9565 If the given package output is not available in the store, @command{guix
9566 graph} attempts to obtain dependency information from substitutes.
9568 Here you can also pass a store file name instead of a package name. For
9569 example, the command below produces the reference graph of your profile
9570 (which can be big!):
9573 guix graph -t references `readlink -f ~/.guix-profile`
9577 This is the graph of the @dfn{referrers} of a store item, as returned by
9578 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
9580 This relies exclusively on local information from your store. For
9581 instance, let us suppose that the current Inkscape is available in 10
9582 profiles on your machine; @command{guix graph -t referrers inkscape}
9583 will show a graph rooted at Inkscape and with those 10 profiles linked
9586 It can help determine what is preventing a store item from being garbage
9591 The available options are the following:
9594 @item --type=@var{type}
9595 @itemx -t @var{type}
9596 Produce a graph output of @var{type}, where @var{type} must be one of
9597 the values listed above.
9600 List the supported graph types.
9602 @item --backend=@var{backend}
9603 @itemx -b @var{backend}
9604 Produce a graph using the selected @var{backend}.
9606 @item --list-backends
9607 List the supported graph backends.
9609 Currently, the available backends are Graphviz and d3.js.
9611 @item --expression=@var{expr}
9612 @itemx -e @var{expr}
9613 Consider the package @var{expr} evaluates to.
9615 This is useful to precisely refer to a package, as in this example:
9618 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
9621 @item --system=@var{system}
9622 @itemx -s @var{system}
9623 Display the graph for @var{system}---e.g., @code{i686-linux}.
9625 The package dependency graph is largely architecture-independent, but there
9626 are some architecture-dependent bits that this option allows you to visualize.
9631 @node Invoking guix publish
9632 @section Invoking @command{guix publish}
9634 @cindex @command{guix publish}
9635 The purpose of @command{guix publish} is to enable users to easily share
9636 their store with others, who can then use it as a substitute server
9637 (@pxref{Substitutes}).
9639 When @command{guix publish} runs, it spawns an HTTP server which allows
9640 anyone with network access to obtain substitutes from it. This means
9641 that any machine running Guix can also act as if it were a build farm,
9642 since the HTTP interface is compatible with Cuirass, the software behind
9643 the @code{@value{SUBSTITUTE-SERVER}} build farm.
9645 For security, each substitute is signed, allowing recipients to check
9646 their authenticity and integrity (@pxref{Substitutes}). Because
9647 @command{guix publish} uses the signing key of the system, which is only
9648 readable by the system administrator, it must be started as root; the
9649 @code{--user} option makes it drop root privileges early on.
9651 The signing key pair must be generated before @command{guix publish} is
9652 launched, using @command{guix archive --generate-key} (@pxref{Invoking
9655 The general syntax is:
9658 guix publish @var{options}@dots{}
9661 Running @command{guix publish} without any additional arguments will
9662 spawn an HTTP server on port 8080:
9668 Once a publishing server has been authorized (@pxref{Invoking guix
9669 archive}), the daemon may download substitutes from it:
9672 guix-daemon --substitute-urls=http://example.org:8080
9675 By default, @command{guix publish} compresses archives on the fly as it
9676 serves them. This ``on-the-fly'' mode is convenient in that it requires
9677 no setup and is immediately available. However, when serving lots of
9678 clients, we recommend using the @option{--cache} option, which enables
9679 caching of the archives before they are sent to clients---see below for
9680 details. The @command{guix weather} command provides a handy way to
9681 check what a server provides (@pxref{Invoking guix weather}).
9683 As a bonus, @command{guix publish} also serves as a content-addressed
9684 mirror for source files referenced in @code{origin} records
9685 (@pxref{origin Reference}). For instance, assuming @command{guix
9686 publish} is running on @code{example.org}, the following URL returns the
9687 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
9688 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
9691 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
9694 Obviously, these URLs only work for files that are in the store; in
9695 other cases, they return 404 (``Not Found'').
9697 @cindex build logs, publication
9698 Build logs are available from @code{/log} URLs like:
9701 http://example.org/log/gwspk@dots{}-guile-2.2.3
9705 When @command{guix-daemon} is configured to save compressed build logs,
9706 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
9707 URLs return the compressed log as-is, with an appropriate
9708 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
9709 running @command{guix-daemon} with @code{--log-compression=gzip} since
9710 Web browsers can automatically decompress it, which is not the case with
9713 The following options are available:
9716 @item --port=@var{port}
9717 @itemx -p @var{port}
9718 Listen for HTTP requests on @var{port}.
9720 @item --listen=@var{host}
9721 Listen on the network interface for @var{host}. The default is to
9722 accept connections from any interface.
9724 @item --user=@var{user}
9725 @itemx -u @var{user}
9726 Change privileges to @var{user} as soon as possible---i.e., once the
9727 server socket is open and the signing key has been read.
9729 @item --compression[=@var{method}[:@var{level}]]
9730 @itemx -C [@var{method}[:@var{level}]]
9731 Compress data using the given @var{method} and @var{level}. @var{method} is
9732 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
9735 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
9736 to different compression levels: 1 is the fastest, and 9 is the best
9737 (CPU-intensive). The default is 3.
9739 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
9740 increase in CPU usage; see
9741 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
9744 Unless @option{--cache} is used, compression occurs on the fly and
9745 the compressed streams are not
9746 cached. Thus, to reduce load on the machine that runs @command{guix
9747 publish}, it may be a good idea to choose a low compression level, to
9748 run @command{guix publish} behind a caching proxy, or to use
9749 @option{--cache}. Using @option{--cache} has the advantage that it
9750 allows @command{guix publish} to add @code{Content-Length} HTTP header
9753 This option can be repeated, in which case every substitute gets compressed
9754 using all the selected methods, and all of them are advertised. This is
9755 useful when users may not support all the compression methods: they can select
9756 the one they support.
9758 @item --cache=@var{directory}
9759 @itemx -c @var{directory}
9760 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
9761 and only serve archives that are in cache.
9763 When this option is omitted, archives and meta-data are created
9764 on-the-fly. This can reduce the available bandwidth, especially when
9765 compression is enabled, since this may become CPU-bound. Another
9766 drawback of the default mode is that the length of archives is not known
9767 in advance, so @command{guix publish} does not add a
9768 @code{Content-Length} HTTP header to its responses, which in turn
9769 prevents clients from knowing the amount of data being downloaded.
9771 Conversely, when @option{--cache} is used, the first request for a store
9772 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
9773 background process to @dfn{bake} the archive---computing its
9774 @code{.narinfo} and compressing the archive, if needed. Once the
9775 archive is cached in @var{directory}, subsequent requests succeed and
9776 are served directly from the cache, which guarantees that clients get
9777 the best possible bandwidth.
9779 The ``baking'' process is performed by worker threads. By default, one
9780 thread per CPU core is created, but this can be customized. See
9781 @option{--workers} below.
9783 When @option{--ttl} is used, cached entries are automatically deleted
9784 when they have expired.
9786 @item --workers=@var{N}
9787 When @option{--cache} is used, request the allocation of @var{N} worker
9788 threads to ``bake'' archives.
9790 @item --ttl=@var{ttl}
9791 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
9792 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
9793 days, @code{1m} means 1 month, and so on.
9795 This allows the user's Guix to keep substitute information in cache for
9796 @var{ttl}. However, note that @code{guix publish} does not itself
9797 guarantee that the store items it provides will indeed remain available
9798 for as long as @var{ttl}.
9800 Additionally, when @option{--cache} is used, cached entries that have
9801 not been accessed for @var{ttl} and that no longer have a corresponding
9802 item in the store, may be deleted.
9804 @item --nar-path=@var{path}
9805 Use @var{path} as the prefix for the URLs of ``nar'' files
9806 (@pxref{Invoking guix archive, normalized archives}).
9808 By default, nars are served at a URL such as
9809 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
9810 change the @code{/nar} part to @var{path}.
9812 @item --public-key=@var{file}
9813 @itemx --private-key=@var{file}
9814 Use the specific @var{file}s as the public/private key pair used to sign
9815 the store items being published.
9817 The files must correspond to the same key pair (the private key is used
9818 for signing and the public key is merely advertised in the signature
9819 metadata). They must contain keys in the canonical s-expression format
9820 as produced by @command{guix archive --generate-key} (@pxref{Invoking
9821 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
9822 @file{/etc/guix/signing-key.sec} are used.
9824 @item --repl[=@var{port}]
9825 @itemx -r [@var{port}]
9826 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
9827 Reference Manual}) on @var{port} (37146 by default). This is used
9828 primarily for debugging a running @command{guix publish} server.
9831 Enabling @command{guix publish} on Guix System is a one-liner: just
9832 instantiate a @code{guix-publish-service-type} service in the @code{services} field
9833 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
9834 @code{guix-publish-service-type}}).
9836 If you are instead running Guix on a ``foreign distro'', follow these
9841 If your host distro uses the systemd init system:
9844 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
9845 /etc/systemd/system/
9846 # systemctl start guix-publish && systemctl enable guix-publish
9850 If your host distro uses the Upstart init system:
9853 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
9854 # start guix-publish
9858 Otherwise, proceed similarly with your distro's init system.
9861 @node Invoking guix challenge
9862 @section Invoking @command{guix challenge}
9864 @cindex reproducible builds
9865 @cindex verifiable builds
9866 @cindex @command{guix challenge}
9868 Do the binaries provided by this server really correspond to the source
9869 code it claims to build? Is a package build process deterministic?
9870 These are the questions the @command{guix challenge} command attempts to
9873 The former is obviously an important question: Before using a substitute
9874 server (@pxref{Substitutes}), one had better @emph{verify} that it
9875 provides the right binaries, and thus @emph{challenge} it. The latter
9876 is what enables the former: If package builds are deterministic, then
9877 independent builds of the package should yield the exact same result,
9878 bit for bit; if a server provides a binary different from the one
9879 obtained locally, it may be either corrupt or malicious.
9881 We know that the hash that shows up in @file{/gnu/store} file names is
9882 the hash of all the inputs of the process that built the file or
9883 directory---compilers, libraries, build scripts,
9884 etc. (@pxref{Introduction}). Assuming deterministic build processes,
9885 one store file name should map to exactly one build output.
9886 @command{guix challenge} checks whether there is, indeed, a single
9887 mapping by comparing the build outputs of several independent builds of
9888 any given store item.
9890 The command output looks like this:
9893 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
9894 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
9895 updating list of substitutes from 'https://guix.example.org'... 100.0%
9896 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
9897 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9898 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9899 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
9900 /gnu/store/@dots{}-git-2.5.0 contents differ:
9901 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
9902 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
9903 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
9904 /gnu/store/@dots{}-pius-2.1.1 contents differ:
9905 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9906 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9907 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
9911 6,406 store items were analyzed:
9912 - 4,749 (74.1%) were identical
9913 - 525 (8.2%) differed
9914 - 1,132 (17.7%) were inconclusive
9918 In this example, @command{guix challenge} first scans the store to
9919 determine the set of locally-built derivations---as opposed to store
9920 items that were downloaded from a substitute server---and then queries
9921 all the substitute servers. It then reports those store items for which
9922 the servers obtained a result different from the local build.
9924 @cindex non-determinism, in package builds
9925 As an example, @code{guix.example.org} always gets a different answer.
9926 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
9927 case of Git. This might indicate that the build process of Git is
9928 non-deterministic, meaning that its output varies as a function of
9929 various things that Guix does not fully control, in spite of building
9930 packages in isolated environments (@pxref{Features}). Most common
9931 sources of non-determinism include the addition of timestamps in build
9932 results, the inclusion of random numbers, and directory listings sorted
9933 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
9936 To find out what is wrong with this Git binary, we can do something along
9937 these lines (@pxref{Invoking guix archive}):
9940 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0 \
9941 | guix archive -x /tmp/git
9942 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
9945 This command shows the difference between the files resulting from the
9946 local build, and the files resulting from the build on
9947 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
9948 diffutils, Comparing and Merging Files}). The @command{diff} command
9949 works great for text files. When binary files differ, a better option
9950 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
9951 visualize differences for all kinds of files.
9953 Once you have done that work, you can tell whether the differences are due
9954 to a non-deterministic build process or to a malicious server. We try
9955 hard to remove sources of non-determinism in packages to make it easier
9956 to verify substitutes, but of course, this is a process that
9957 involves not just Guix, but a large part of the free software community.
9958 In the meantime, @command{guix challenge} is one tool to help address
9961 If you are writing packages for Guix, you are encouraged to check
9962 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
9963 same build result as you did with:
9966 $ guix challenge @var{package}
9970 where @var{package} is a package specification such as
9971 @code{guile@@2.0} or @code{glibc:debug}.
9973 The general syntax is:
9976 guix challenge @var{options} [@var{packages}@dots{}]
9979 When a difference is found between the hash of a locally-built item and
9980 that of a server-provided substitute, or among substitutes provided by
9981 different servers, the command displays it as in the example above and
9982 its exit code is 2 (other non-zero exit codes denote other kinds of
9985 The one option that matters is:
9989 @item --substitute-urls=@var{urls}
9990 Consider @var{urls} the whitespace-separated list of substitute source
9995 Show details about matches (identical contents) in addition to
9996 information about mismatches.
10000 @node Invoking guix copy
10001 @section Invoking @command{guix copy}
10003 @cindex copy, of store items, over SSH
10004 @cindex SSH, copy of store items
10005 @cindex sharing store items across machines
10006 @cindex transferring store items across machines
10007 The @command{guix copy} command copies items from the store of one
10008 machine to that of another machine over a secure shell (SSH)
10009 connection@footnote{This command is available only when Guile-SSH was
10010 found. @xref{Requirements}, for details.}. For example, the following
10011 command copies the @code{coreutils} package, the user's profile, and all
10012 their dependencies over to @var{host}, logged in as @var{user}:
10015 guix copy --to=@var{user}@@@var{host} \
10016 coreutils `readlink -f ~/.guix-profile`
10019 If some of the items to be copied are already present on @var{host},
10020 they are not actually sent.
10022 The command below retrieves @code{libreoffice} and @code{gimp} from
10023 @var{host}, assuming they are available there:
10026 guix copy --from=@var{host} libreoffice gimp
10029 The SSH connection is established using the Guile-SSH client, which is
10030 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10031 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10033 The key used to sign items that are sent must be accepted by the remote
10034 machine. Likewise, the key used by the remote machine to sign items you
10035 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10036 own daemon. @xref{Invoking guix archive}, for more information about
10037 store item authentication.
10039 The general syntax is:
10042 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10045 You must always specify one of the following options:
10048 @item --to=@var{spec}
10049 @itemx --from=@var{spec}
10050 Specify the host to send to or receive from. @var{spec} must be an SSH
10051 spec such as @code{example.org}, @code{charlie@@example.org}, or
10052 @code{charlie@@example.org:2222}.
10055 The @var{items} can be either package names, such as @code{gimp}, or
10056 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10058 When specifying the name of a package to send, it is first built if
10059 needed, unless @option{--dry-run} was specified. Common build options
10060 are supported (@pxref{Common Build Options}).
10063 @node Invoking guix container
10064 @section Invoking @command{guix container}
10066 @cindex @command{guix container}
10068 As of version @value{VERSION}, this tool is experimental. The interface
10069 is subject to radical change in the future.
10072 The purpose of @command{guix container} is to manipulate processes
10073 running within an isolated environment, commonly known as a
10074 ``container'', typically created by the @command{guix environment}
10075 (@pxref{Invoking guix environment}) and @command{guix system container}
10076 (@pxref{Invoking guix system}) commands.
10078 The general syntax is:
10081 guix container @var{action} @var{options}@dots{}
10084 @var{action} specifies the operation to perform with a container, and
10085 @var{options} specifies the context-specific arguments for the action.
10087 The following actions are available:
10091 Execute a command within the context of a running container.
10096 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10099 @var{pid} specifies the process ID of the running container.
10100 @var{program} specifies an executable file name within the root file
10101 system of the container. @var{arguments} are the additional options that
10102 will be passed to @var{program}.
10104 The following command launches an interactive login shell inside a
10105 Guix system container, started by @command{guix system container}, and whose
10106 process ID is 9001:
10109 guix container exec 9001 /run/current-system/profile/bin/bash --login
10112 Note that the @var{pid} cannot be the parent process of a container. It
10113 must be PID 1 of the container or one of its child processes.
10117 @node Invoking guix weather
10118 @section Invoking @command{guix weather}
10120 Occasionally you're grumpy because substitutes are lacking and you end
10121 up building packages by yourself (@pxref{Substitutes}). The
10122 @command{guix weather} command reports on substitute availability on the
10123 specified servers so you can have an idea of whether you'll be grumpy
10124 today. It can sometimes be useful info as a user, but it is primarily
10125 useful to people running @command{guix publish} (@pxref{Invoking guix
10128 @cindex statistics, for substitutes
10129 @cindex availability of substitutes
10130 @cindex substitute availability
10131 @cindex weather, substitute availability
10132 Here's a sample run:
10135 $ guix weather --substitute-urls=https://guix.example.org
10136 computing 5,872 package derivations for x86_64-linux...
10137 looking for 6,128 store items on https://guix.example.org..
10138 updating list of substitutes from 'https://guix.example.org'... 100.0%
10139 https://guix.example.org
10140 43.4% substitutes available (2,658 out of 6,128)
10141 7,032.5 MiB of nars (compressed)
10142 19,824.2 MiB on disk (uncompressed)
10143 0.030 seconds per request (182.9 seconds in total)
10144 33.5 requests per second
10146 9.8% (342 out of 3,470) of the missing items are queued
10148 x86_64-linux: 518 (59.7%)
10149 i686-linux: 221 (25.5%)
10150 aarch64-linux: 128 (14.8%)
10151 build rate: 23.41 builds per hour
10152 x86_64-linux: 11.16 builds per hour
10153 i686-linux: 6.03 builds per hour
10154 aarch64-linux: 6.41 builds per hour
10157 @cindex continuous integration, statistics
10158 As you can see, it reports the fraction of all the packages for which
10159 substitutes are available on the server---regardless of whether
10160 substitutes are enabled, and regardless of whether this server's signing
10161 key is authorized. It also reports the size of the compressed archives
10162 (``nars'') provided by the server, the size the corresponding store
10163 items occupy in the store (assuming deduplication is turned off), and
10164 the server's throughput. The second part gives continuous integration
10165 (CI) statistics, if the server supports it. In addition, using the
10166 @option{--coverage} option, @command{guix weather} can list ``important''
10167 package substitutes missing on the server (see below).
10169 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10170 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10171 challenge}, it ignores signatures on those substitutes, which is
10172 innocuous since the command only gathers statistics and cannot install
10175 The general syntax is:
10178 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10181 When @var{packages} is omitted, @command{guix weather} checks the availability
10182 of substitutes for @emph{all} the packages, or for those specified with
10183 @option{--manifest}; otherwise it only considers the specified packages. It
10184 is also possible to query specific system types with @option{--system}. The
10185 available options are listed below.
10188 @item --substitute-urls=@var{urls}
10189 @var{urls} is the space-separated list of substitute server URLs to
10190 query. When this option is omitted, the default set of substitute
10191 servers is queried.
10193 @item --system=@var{system}
10194 @itemx -s @var{system}
10195 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10196 option can be repeated, in which case @command{guix weather} will query
10197 substitutes for several system types.
10199 @item --manifest=@var{file}
10200 Instead of querying substitutes for all the packages, only ask for those
10201 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10202 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10205 @item --coverage[=@var{count}]
10206 @itemx -c [@var{count}]
10207 Report on substitute coverage for packages: list packages with at least
10208 @var{count} dependents (zero by default) for which substitutes are
10209 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10210 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10211 @var{b} usually lacks substitutes as well. The result looks like this:
10214 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10215 computing 8,983 package derivations for x86_64-linux...
10216 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10217 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10218 @value{SUBSTITUTE-URL}
10219 64.7% substitutes available (6,047 out of 9,343)
10221 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10222 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10223 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10224 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10228 What this example shows is that @code{kcoreaddons} and presumably the 58
10229 packages that depend on it have no substitutes at @code{ci.guix.info};
10230 likewise for @code{qgpgme} and the 46 packages that depend on it.
10232 If you are a Guix developer, or if you are taking care of this build farm,
10233 you'll probably want to have a closer look at these packages: they may simply
10237 @node Invoking guix processes
10238 @section Invoking @command{guix processes}
10240 The @command{guix processes} command can be useful to developers and system
10241 administrators, especially on multi-user machines and on build farms: it lists
10242 the current sessions (connections to the daemon), as well as information about
10243 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10244 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10245 listed.}. Here's an example of the information it returns:
10248 $ sudo guix processes
10251 ClientCommand: guix environment --ad-hoc python
10255 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10259 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10260 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10261 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10262 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10263 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10264 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10265 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10268 In this example we see that @command{guix-daemon} has three clients:
10269 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10270 integration tool; their process identifier (PID) is given by the
10271 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10272 @command{guix-daemon} sub-process of this particular session.
10274 The @code{LockHeld} fields show which store items are currently locked by this
10275 session, which corresponds to store items being built or substituted (the
10276 @code{LockHeld} field is not displayed when @command{guix processes} is not
10277 running as root.) Last, by looking at the @code{ChildProcess} field, we
10278 understand that these three builds are being offloaded (@pxref{Daemon Offload
10281 The output is in Recutils format so we can use the handy @command{recsel}
10282 command to select sessions of interest (@pxref{Selection Expressions,,,
10283 recutils, GNU recutils manual}). As an example, the command shows the command
10284 line and PID of the client that triggered the build of a Perl package:
10287 $ sudo guix processes | \
10288 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10290 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10294 @node System Configuration
10295 @chapter System Configuration
10297 @cindex system configuration
10298 Guix System supports a consistent whole-system configuration
10299 mechanism. By that we mean that all aspects of the global system
10300 configuration---such as the available system services, timezone and
10301 locale settings, user accounts---are declared in a single place. Such
10302 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10304 One of the advantages of putting all the system configuration under the
10305 control of Guix is that it supports transactional system upgrades, and
10306 makes it possible to roll back to a previous system instantiation,
10307 should something go wrong with the new one (@pxref{Features}). Another
10308 advantage is that it makes it easy to replicate the exact same configuration
10309 across different machines, or at different points in time, without
10310 having to resort to additional administration tools layered on top of
10311 the own tools of the system.
10312 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10314 This section describes this mechanism. First we focus on the system
10315 administrator's viewpoint---explaining how the system is configured and
10316 instantiated. Then we show how this mechanism can be extended, for
10317 instance to support new system services.
10320 * Using the Configuration System:: Customizing your GNU system.
10321 * operating-system Reference:: Detail of operating-system declarations.
10322 * File Systems:: Configuring file system mounts.
10323 * Mapped Devices:: Block device extra processing.
10324 * User Accounts:: Specifying user accounts.
10325 * Keyboard Layout:: How the system interprets key strokes.
10326 * Locales:: Language and cultural convention settings.
10327 * Services:: Specifying system services.
10328 * Setuid Programs:: Programs running with root privileges.
10329 * X.509 Certificates:: Authenticating HTTPS servers.
10330 * Name Service Switch:: Configuring libc's name service switch.
10331 * Initial RAM Disk:: Linux-Libre bootstrapping.
10332 * Bootloader Configuration:: Configuring the boot loader.
10333 * Invoking guix system:: Instantiating a system configuration.
10334 * Invoking guix deploy:: Deploying a system configuration to a remote host.
10335 * Running Guix in a VM:: How to run Guix System in a virtual machine.
10336 * Defining Services:: Adding new service definitions.
10339 @node Using the Configuration System
10340 @section Using the Configuration System
10342 The operating system is configured by providing an
10343 @code{operating-system} declaration in a file that can then be passed to
10344 the @command{guix system} command (@pxref{Invoking guix system}). A
10345 simple setup, with the default system services, the default Linux-Libre
10346 kernel, initial RAM disk, and boot loader looks like this:
10348 @findex operating-system
10350 @include os-config-bare-bones.texi
10353 This example should be self-describing. Some of the fields defined
10354 above, such as @code{host-name} and @code{bootloader}, are mandatory.
10355 Others, such as @code{packages} and @code{services}, can be omitted, in
10356 which case they get a default value.
10358 Below we discuss the effect of some of the most important fields
10359 (@pxref{operating-system Reference}, for details about all the available
10360 fields), and how to @dfn{instantiate} the operating system using
10361 @command{guix system}.
10363 @unnumberedsubsec Bootloader
10365 @cindex legacy boot, on Intel machines
10366 @cindex BIOS boot, on Intel machines
10369 The @code{bootloader} field describes the method that will be used to boot
10370 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
10371 mode, as in the example above. However, more recent machines rely instead on
10372 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
10373 the @code{bootloader} field should contain something along these lines:
10376 (bootloader-configuration
10377 (bootloader grub-efi-bootloader)
10378 (target "/boot/efi"))
10381 @xref{Bootloader Configuration}, for more information on the available
10382 configuration options.
10384 @unnumberedsubsec Globally-Visible Packages
10386 @vindex %base-packages
10387 The @code{packages} field lists packages that will be globally visible
10388 on the system, for all user accounts---i.e., in every user's @code{PATH}
10389 environment variable---in addition to the per-user profiles
10390 (@pxref{Invoking guix package}). The @code{%base-packages} variable
10391 provides all the tools one would expect for basic user and administrator
10392 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
10393 the GNU Zile lightweight text editor, @command{find}, @command{grep},
10394 etc. The example above adds GNU@tie{}Screen to those,
10395 taken from the @code{(gnu packages screen)}
10396 module (@pxref{Package Modules}). The
10397 @code{(list package output)} syntax can be used to add a specific output
10401 (use-modules (gnu packages))
10402 (use-modules (gnu packages dns))
10406 (packages (cons (list bind "utils")
10410 @findex specification->package
10411 Referring to packages by variable name, like @code{bind} above, has
10412 the advantage of being unambiguous; it also allows typos and such to be
10413 diagnosed right away as ``unbound variables''. The downside is that one
10414 needs to know which module defines which package, and to augment the
10415 @code{use-package-modules} line accordingly. To avoid that, one can use
10416 the @code{specification->package} procedure of the @code{(gnu packages)}
10417 module, which returns the best package for a given name or name and
10421 (use-modules (gnu packages))
10425 (packages (append (map specification->package
10426 '("tcpdump" "htop" "gnupg@@2.0"))
10430 @unnumberedsubsec System Services
10433 @vindex %base-services
10434 The @code{services} field lists @dfn{system services} to be made
10435 available when the system starts (@pxref{Services}).
10436 The @code{operating-system} declaration above specifies that, in
10437 addition to the basic services, we want the OpenSSH secure shell
10438 daemon listening on port 2222 (@pxref{Networking Services,
10439 @code{openssh-service-type}}). Under the hood,
10440 @code{openssh-service-type} arranges so that @command{sshd} is started with the
10441 right command-line options, possibly with supporting configuration files
10442 generated as needed (@pxref{Defining Services}).
10444 @cindex customization, of services
10445 @findex modify-services
10446 Occasionally, instead of using the base services as is, you will want to
10447 customize them. To do this, use @code{modify-services} (@pxref{Service
10448 Reference, @code{modify-services}}) to modify the list.
10450 For example, suppose you want to modify @code{guix-daemon} and Mingetty
10451 (the console log-in) in the @code{%base-services} list (@pxref{Base
10452 Services, @code{%base-services}}). To do that, you can write the
10453 following in your operating system declaration:
10456 (define %my-services
10457 ;; My very own list of services.
10458 (modify-services %base-services
10459 (guix-service-type config =>
10460 (guix-configuration
10462 (use-substitutes? #f)
10463 (extra-options '("--gc-keep-derivations"))))
10464 (mingetty-service-type config =>
10465 (mingetty-configuration
10466 (inherit config)))))
10470 (services %my-services))
10473 This changes the configuration---i.e., the service parameters---of the
10474 @code{guix-service-type} instance, and that of all the
10475 @code{mingetty-service-type} instances in the @code{%base-services} list.
10476 Observe how this is accomplished: first, we arrange for the original
10477 configuration to be bound to the identifier @code{config} in the
10478 @var{body}, and then we write the @var{body} so that it evaluates to the
10479 desired configuration. In particular, notice how we use @code{inherit}
10480 to create a new configuration which has the same values as the old
10481 configuration, but with a few modifications.
10483 @cindex encrypted disk
10484 The configuration for a typical ``desktop'' usage, with an encrypted
10485 root partition, the X11 display
10486 server, GNOME and Xfce (users can choose which of these desktop
10487 environments to use at the log-in screen by pressing @kbd{F1}), network
10488 management, power management, and more, would look like this:
10491 @include os-config-desktop.texi
10494 A graphical system with a choice of lightweight window managers
10495 instead of full-blown desktop environments would look like this:
10498 @include os-config-lightweight-desktop.texi
10501 This example refers to the @file{/boot/efi} file system by its UUID,
10502 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
10503 as returned by the @command{blkid} command.
10505 @xref{Desktop Services}, for the exact list of services provided by
10506 @code{%desktop-services}. @xref{X.509 Certificates}, for background
10507 information about the @code{nss-certs} package that is used here.
10509 Again, @code{%desktop-services} is just a list of service objects. If
10510 you want to remove services from there, you can do so using the
10511 procedures for list filtering (@pxref{SRFI-1 Filtering and
10512 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
10513 following expression returns a list that contains all the services in
10514 @code{%desktop-services} minus the Avahi service:
10517 (remove (lambda (service)
10518 (eq? (service-kind service) avahi-service-type))
10522 @unnumberedsubsec Instantiating the System
10524 Assuming the @code{operating-system} declaration
10525 is stored in the @file{my-system-config.scm}
10526 file, the @command{guix system reconfigure my-system-config.scm} command
10527 instantiates that configuration, and makes it the default GRUB boot
10528 entry (@pxref{Invoking guix system}).
10530 The normal way to change the system configuration is by updating this
10531 file and re-running @command{guix system reconfigure}. One should never
10532 have to touch files in @file{/etc} or to run commands that modify the
10533 system state such as @command{useradd} or @command{grub-install}. In
10534 fact, you must avoid that since that would not only void your warranty
10535 but also prevent you from rolling back to previous versions of your
10536 system, should you ever need to.
10538 @cindex roll-back, of the operating system
10539 Speaking of roll-back, each time you run @command{guix system
10540 reconfigure}, a new @dfn{generation} of the system is created---without
10541 modifying or deleting previous generations. Old system generations get
10542 an entry in the bootloader boot menu, allowing you to boot them in case
10543 something went wrong with the latest generation. Reassuring, no? The
10544 @command{guix system list-generations} command lists the system
10545 generations available on disk. It is also possible to roll back the
10546 system via the commands @command{guix system roll-back} and
10547 @command{guix system switch-generation}.
10549 Although the @command{guix system reconfigure} command will not modify
10550 previous generations, you must take care when the current generation is not
10551 the latest (e.g., after invoking @command{guix system roll-back}), since
10552 the operation might overwrite a later generation (@pxref{Invoking guix
10555 @unnumberedsubsec The Programming Interface
10557 At the Scheme level, the bulk of an @code{operating-system} declaration
10558 is instantiated with the following monadic procedure (@pxref{The Store
10561 @deffn {Monadic Procedure} operating-system-derivation os
10562 Return a derivation that builds @var{os}, an @code{operating-system}
10563 object (@pxref{Derivations}).
10565 The output of the derivation is a single directory that refers to all
10566 the packages, configuration files, and other supporting files needed to
10567 instantiate @var{os}.
10570 This procedure is provided by the @code{(gnu system)} module. Along
10571 with @code{(gnu services)} (@pxref{Services}), this module contains the
10572 guts of Guix System. Make sure to visit it!
10575 @node operating-system Reference
10576 @section @code{operating-system} Reference
10578 This section summarizes all the options available in
10579 @code{operating-system} declarations (@pxref{Using the Configuration
10582 @deftp {Data Type} operating-system
10583 This is the data type representing an operating system configuration.
10584 By that, we mean all the global system configuration, not per-user
10585 configuration (@pxref{Using the Configuration System}).
10588 @item @code{kernel} (default: @var{linux-libre})
10589 The package object of the operating system kernel to use@footnote{Currently
10590 only the Linux-libre kernel is supported. In the future, it will be
10591 possible to use the GNU@tie{}Hurd.}.
10593 @item @code{kernel-arguments} (default: @code{'("quiet")})
10594 List of strings or gexps representing additional arguments to pass on
10595 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
10597 @item @code{bootloader}
10598 The system bootloader configuration object. @xref{Bootloader Configuration}.
10601 This is the label (a string) as it appears in the bootloader's menu entry.
10602 The default label includes the kernel name and version.
10604 @item @code{keyboard-layout} (default: @code{#f})
10605 This field specifies the keyboard layout to use in the console. It can be
10606 either @code{#f}, in which case the default keyboard layout is used (usually
10607 US English), or a @code{<keyboard-layout>} record.
10609 This keyboard layout is in effect as soon as the kernel has booted. For
10610 instance, it is the keyboard layout in effect when you type a passphrase if
10611 your root file system is on a @code{luks-device-mapping} mapped device
10612 (@pxref{Mapped Devices}).
10615 This does @emph{not} specify the keyboard layout used by the bootloader, nor
10616 that used by the graphical display server. @xref{Bootloader Configuration},
10617 for information on how to specify the bootloader's keyboard layout. @xref{X
10618 Window}, for information on how to specify the keyboard layout used by the X
10622 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
10624 @cindex initial RAM disk
10625 The list of Linux kernel modules that need to be available in the
10626 initial RAM disk. @xref{Initial RAM Disk}.
10628 @item @code{initrd} (default: @code{base-initrd})
10629 A procedure that returns an initial RAM disk for the Linux
10630 kernel. This field is provided to support low-level customization and
10631 should rarely be needed for casual use. @xref{Initial RAM Disk}.
10633 @item @code{firmware} (default: @code{%base-firmware})
10635 List of firmware packages loadable by the operating system kernel.
10637 The default includes firmware needed for Atheros- and Broadcom-based
10638 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
10639 respectively). @xref{Hardware Considerations}, for more info on
10640 supported hardware.
10642 @item @code{host-name}
10645 @item @code{hosts-file}
10647 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
10648 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
10649 Reference Manual}). The default is a file with entries for
10650 @code{localhost} and @var{host-name}.
10652 @item @code{mapped-devices} (default: @code{'()})
10653 A list of mapped devices. @xref{Mapped Devices}.
10655 @item @code{file-systems}
10656 A list of file systems. @xref{File Systems}.
10658 @item @code{swap-devices} (default: @code{'()})
10659 @cindex swap devices
10660 A list of strings identifying devices or files to be used for ``swap
10661 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
10662 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
10663 It is possible to specify a swap file in a file system on a mapped
10664 device, provided that the necessary device mapping and file system are
10665 also specified. @xref{Mapped Devices} and @ref{File Systems}.
10667 @item @code{users} (default: @code{%base-user-accounts})
10668 @itemx @code{groups} (default: @code{%base-groups})
10669 List of user accounts and groups. @xref{User Accounts}.
10671 If the @code{users} list lacks a user account with UID@tie{}0, a
10672 ``root'' account with UID@tie{}0 is automatically added.
10674 @item @code{skeletons} (default: @code{(default-skeletons)})
10675 A list target file name/file-like object tuples (@pxref{G-Expressions,
10676 file-like objects}). These are the skeleton files that will be added to
10677 the home directory of newly-created user accounts.
10679 For instance, a valid value may look like this:
10682 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
10683 (".guile" ,(plain-file "guile"
10684 "(use-modules (ice-9 readline))
10685 (activate-readline)")))
10688 @item @code{issue} (default: @code{%default-issue})
10689 A string denoting the contents of the @file{/etc/issue} file, which is
10690 displayed when users log in on a text console.
10692 @item @code{packages} (default: @code{%base-packages})
10693 The set of packages installed in the global profile, which is accessible
10694 at @file{/run/current-system/profile}.
10696 The default set includes core utilities and it is good practice to
10697 install non-core utilities in user profiles (@pxref{Invoking guix
10700 @item @code{timezone}
10701 A timezone identifying string---e.g., @code{"Europe/Paris"}.
10703 You can run the @command{tzselect} command to find out which timezone
10704 string corresponds to your region. Choosing an invalid timezone name
10705 causes @command{guix system} to fail.
10707 @item @code{locale} (default: @code{"en_US.utf8"})
10708 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
10709 Library Reference Manual}). @xref{Locales}, for more information.
10711 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
10712 The list of locale definitions to be compiled and that may be used at
10713 run time. @xref{Locales}.
10715 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
10716 The list of GNU@tie{}libc packages whose locale data and tools are used
10717 to build the locale definitions. @xref{Locales}, for compatibility
10718 considerations that justify this option.
10720 @item @code{name-service-switch} (default: @code{%default-nss})
10721 Configuration of the libc name service switch (NSS)---a
10722 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
10725 @item @code{services} (default: @code{%base-services})
10726 A list of service objects denoting system services. @xref{Services}.
10728 @cindex essential services
10729 @item @code{essential-services} (default: ...)
10730 The list of ``essential services''---i.e., things like instances of
10731 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
10732 Reference}), which are derived from the operating system definition itself.
10733 As a user you should @emph{never} need to touch this field.
10735 @item @code{pam-services} (default: @code{(base-pam-services)})
10737 @cindex pluggable authentication modules
10738 Linux @dfn{pluggable authentication module} (PAM) services.
10739 @c FIXME: Add xref to PAM services section.
10741 @item @code{setuid-programs} (default: @var{%setuid-programs})
10742 List of string-valued G-expressions denoting setuid programs.
10743 @xref{Setuid Programs}.
10745 @item @code{sudoers-file} (default: @var{%sudoers-specification})
10746 @cindex sudoers file
10747 The contents of the @file{/etc/sudoers} file as a file-like object
10748 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
10750 This file specifies which users can use the @command{sudo} command, what
10751 they are allowed to do, and what privileges they may gain. The default
10752 is that only @code{root} and members of the @code{wheel} group may use
10757 @deffn {Scheme Syntax} this-operating-system
10758 When used in the @emph{lexical scope} of an operating system field definition,
10759 this identifier resolves to the operating system being defined.
10761 The example below shows how to refer to the operating system being defined in
10762 the definition of the @code{label} field:
10765 (use-modules (gnu) (guix))
10769 (label (package-full-name
10770 (operating-system-kernel this-operating-system))))
10773 It is an error to refer to @code{this-operating-system} outside an operating
10780 @section File Systems
10782 The list of file systems to be mounted is specified in the
10783 @code{file-systems} field of the operating system declaration
10784 (@pxref{Using the Configuration System}). Each file system is declared
10785 using the @code{file-system} form, like this:
10789 (mount-point "/home")
10790 (device "/dev/sda3")
10794 As usual, some of the fields are mandatory---those shown in the example
10795 above---while others can be omitted. These are described below.
10797 @deftp {Data Type} file-system
10798 Objects of this type represent file systems to be mounted. They
10799 contain the following members:
10803 This is a string specifying the type of the file system---e.g.,
10806 @item @code{mount-point}
10807 This designates the place where the file system is to be mounted.
10809 @item @code{device}
10810 This names the ``source'' of the file system. It can be one of three
10811 things: a file system label, a file system UUID, or the name of a
10812 @file{/dev} node. Labels and UUIDs offer a way to refer to file
10813 systems without having to hard-code their actual device
10814 name@footnote{Note that, while it is tempting to use
10815 @file{/dev/disk/by-uuid} and similar device names to achieve the same
10816 result, this is not recommended: These special device nodes are created
10817 by the udev daemon and may be unavailable at the time the device is
10820 @findex file-system-label
10821 File system labels are created using the @code{file-system-label}
10822 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
10823 plain strings. Here's an example of a file system referred to by its
10824 label, as shown by the @command{e2label} command:
10828 (mount-point "/home")
10830 (device (file-system-label "my-home")))
10834 UUIDs are converted from their string representation (as shown by the
10835 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
10836 @code{uuid} form expects 16-byte UUIDs as defined in
10837 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
10838 form of UUID used by the ext2 family of file systems and others, but it
10839 is different from ``UUIDs'' found in FAT file systems, for instance.},
10844 (mount-point "/home")
10846 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
10849 When the source of a file system is a mapped device (@pxref{Mapped
10850 Devices}), its @code{device} field @emph{must} refer to the mapped
10851 device name---e.g., @file{"/dev/mapper/root-partition"}.
10852 This is required so that
10853 the system knows that mounting the file system depends on having the
10854 corresponding device mapping established.
10856 @item @code{flags} (default: @code{'()})
10857 This is a list of symbols denoting mount flags. Recognized flags
10858 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
10859 access to special files), @code{no-suid} (ignore setuid and setgid
10860 bits), @code{no-atime} (do not update file access times), and @code{no-exec}
10861 (disallow program execution). @xref{Mount-Unmount-Remount,,, libc, The GNU C
10862 Library Reference Manual}, for more information on these flags.
10864 @item @code{options} (default: @code{#f})
10865 This is either @code{#f}, or a string denoting mount options passed to the
10866 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
10867 Reference Manual}, for details and run @command{man 8 mount} for options for
10868 various file systems.
10870 @item @code{mount?} (default: @code{#t})
10871 This value indicates whether to automatically mount the file system when
10872 the system is brought up. When set to @code{#f}, the file system gets
10873 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
10874 is not automatically mounted.
10876 @item @code{needed-for-boot?} (default: @code{#f})
10877 This Boolean value indicates whether the file system is needed when
10878 booting. If that is true, then the file system is mounted when the
10879 initial RAM disk (initrd) is loaded. This is always the case, for
10880 instance, for the root file system.
10882 @item @code{check?} (default: @code{#t})
10883 This Boolean indicates whether the file system needs to be checked for
10884 errors before being mounted.
10886 @item @code{create-mount-point?} (default: @code{#f})
10887 When true, the mount point is created if it does not exist yet.
10889 @item @code{dependencies} (default: @code{'()})
10890 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
10891 representing file systems that must be mounted or mapped devices that
10892 must be opened before (and unmounted or closed after) this one.
10894 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
10895 a dependency of @file{/sys/fs/cgroup/cpu} and
10896 @file{/sys/fs/cgroup/memory}.
10898 Another example is a file system that depends on a mapped device, for
10899 example for an encrypted partition (@pxref{Mapped Devices}).
10903 The @code{(gnu system file-systems)} exports the following useful
10906 @defvr {Scheme Variable} %base-file-systems
10907 These are essential file systems that are required on normal systems,
10908 such as @var{%pseudo-terminal-file-system} and @var{%immutable-store} (see
10909 below.) Operating system declarations should always contain at least
10913 @defvr {Scheme Variable} %pseudo-terminal-file-system
10914 This is the file system to be mounted as @file{/dev/pts}. It supports
10915 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
10916 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
10917 Manual}). Pseudo-terminals are used by terminal emulators such as
10921 @defvr {Scheme Variable} %shared-memory-file-system
10922 This file system is mounted as @file{/dev/shm} and is used to support
10923 memory sharing across processes (@pxref{Memory-mapped I/O,
10924 @code{shm_open},, libc, The GNU C Library Reference Manual}).
10927 @defvr {Scheme Variable} %immutable-store
10928 This file system performs a read-only ``bind mount'' of
10929 @file{/gnu/store}, making it read-only for all the users including
10930 @code{root}. This prevents against accidental modification by software
10931 running as @code{root} or by system administrators.
10933 The daemon itself is still able to write to the store: it remounts it
10934 read-write in its own ``name space.''
10937 @defvr {Scheme Variable} %binary-format-file-system
10938 The @code{binfmt_misc} file system, which allows handling of arbitrary
10939 executable file types to be delegated to user space. This requires the
10940 @code{binfmt.ko} kernel module to be loaded.
10943 @defvr {Scheme Variable} %fuse-control-file-system
10944 The @code{fusectl} file system, which allows unprivileged users to mount
10945 and unmount user-space FUSE file systems. This requires the
10946 @code{fuse.ko} kernel module to be loaded.
10949 @node Mapped Devices
10950 @section Mapped Devices
10952 @cindex device mapping
10953 @cindex mapped devices
10954 The Linux kernel has a notion of @dfn{device mapping}: a block device,
10955 such as a hard disk partition, can be @dfn{mapped} into another device,
10956 usually in @code{/dev/mapper/},
10957 with additional processing over the data that flows through
10958 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
10959 concept of a ``mapped device'' and that of a file system: both boil down
10960 to @emph{translating} input/output operations made on a file to
10961 operations on its backing store. Thus, the Hurd implements mapped
10962 devices, like file systems, using the generic @dfn{translator} mechanism
10963 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
10964 typical example is encryption device mapping: all writes to the mapped
10965 device are encrypted, and all reads are deciphered, transparently.
10966 Guix extends this notion by considering any device or set of devices that
10967 are @dfn{transformed} in some way to create a new device; for instance,
10968 RAID devices are obtained by @dfn{assembling} several other devices, such
10969 as hard disks or partitions, into a new one that behaves as one partition.
10970 Other examples, not yet implemented, are LVM logical volumes.
10972 Mapped devices are declared using the @code{mapped-device} form,
10973 defined as follows; for examples, see below.
10975 @deftp {Data Type} mapped-device
10976 Objects of this type represent device mappings that will be made when
10977 the system boots up.
10981 This is either a string specifying the name of the block device to be mapped,
10982 such as @code{"/dev/sda3"}, or a list of such strings when several devices
10983 need to be assembled for creating a new one.
10986 This string specifies the name of the resulting mapped device. For
10987 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
10988 specifying @code{"my-partition"} leads to the creation of
10989 the @code{"/dev/mapper/my-partition"} device.
10990 For RAID devices of type @code{raid-device-mapping}, the full device name
10991 such as @code{"/dev/md0"} needs to be given.
10994 This must be a @code{mapped-device-kind} object, which specifies how
10995 @var{source} is mapped to @var{target}.
10999 @defvr {Scheme Variable} luks-device-mapping
11000 This defines LUKS block device encryption using the @command{cryptsetup}
11001 command from the package with the same name. It relies on the
11002 @code{dm-crypt} Linux kernel module.
11005 @defvr {Scheme Variable} raid-device-mapping
11006 This defines a RAID device, which is assembled using the @code{mdadm}
11007 command from the package with the same name. It requires a Linux kernel
11008 module for the appropriate RAID level to be loaded, such as @code{raid456}
11009 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
11012 @cindex disk encryption
11014 The following example specifies a mapping from @file{/dev/sda3} to
11015 @file{/dev/mapper/home} using LUKS---the
11016 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
11017 standard mechanism for disk encryption.
11018 The @file{/dev/mapper/home}
11019 device can then be used as the @code{device} of a @code{file-system}
11020 declaration (@pxref{File Systems}).
11024 (source "/dev/sda3")
11026 (type luks-device-mapping))
11029 Alternatively, to become independent of device numbering, one may obtain
11030 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11034 cryptsetup luksUUID /dev/sda3
11037 and use it as follows:
11041 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11043 (type luks-device-mapping))
11046 @cindex swap encryption
11047 It is also desirable to encrypt swap space, since swap space may contain
11048 sensitive data. One way to accomplish that is to use a swap file in a
11049 file system on a device mapped via LUKS encryption. In this way, the
11050 swap file is encrypted because the entire device is encrypted.
11051 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11053 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11054 may be declared as follows:
11058 (source (list "/dev/sda1" "/dev/sdb1"))
11059 (target "/dev/md0")
11060 (type raid-device-mapping))
11063 The @file{/dev/md0} device can then be used as the @code{device} of a
11064 @code{file-system} declaration (@pxref{File Systems}).
11065 Note that the RAID level need not be given; it is chosen during the
11066 initial creation and formatting of the RAID device and is determined
11067 automatically later.
11070 @node User Accounts
11071 @section User Accounts
11075 @cindex user accounts
11076 User accounts and groups are entirely managed through the
11077 @code{operating-system} declaration. They are specified with the
11078 @code{user-account} and @code{user-group} forms:
11084 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11085 "audio" ;sound card
11086 "video" ;video devices such as webcams
11087 "cdrom")) ;the good ol' CD-ROM
11088 (comment "Bob's sister")
11089 (home-directory "/home/alice"))
11092 When booting or upon completion of @command{guix system reconfigure},
11093 the system ensures that only the user accounts and groups specified in
11094 the @code{operating-system} declaration exist, and with the specified
11095 properties. Thus, account or group creations or modifications made by
11096 directly invoking commands such as @command{useradd} are lost upon
11097 reconfiguration or reboot. This ensures that the system remains exactly
11100 @deftp {Data Type} user-account
11101 Objects of this type represent user accounts. The following members may
11106 The name of the user account.
11110 This is the name (a string) or identifier (a number) of the user group
11111 this account belongs to.
11113 @item @code{supplementary-groups} (default: @code{'()})
11114 Optionally, this can be defined as a list of group names that this
11115 account belongs to.
11117 @item @code{uid} (default: @code{#f})
11118 This is the user ID for this account (a number), or @code{#f}. In the
11119 latter case, a number is automatically chosen by the system when the
11120 account is created.
11122 @item @code{comment} (default: @code{""})
11123 A comment about the account, such as the account owner's full name.
11125 @item @code{home-directory}
11126 This is the name of the home directory for the account.
11128 @item @code{create-home-directory?} (default: @code{#t})
11129 Indicates whether the home directory of this account should be created
11130 if it does not exist yet.
11132 @item @code{shell} (default: Bash)
11133 This is a G-expression denoting the file name of a program to be used as
11134 the shell (@pxref{G-Expressions}).
11136 @item @code{system?} (default: @code{#f})
11137 This Boolean value indicates whether the account is a ``system''
11138 account. System accounts are sometimes treated specially; for instance,
11139 graphical login managers do not list them.
11141 @anchor{user-account-password}
11142 @cindex password, for user accounts
11143 @item @code{password} (default: @code{#f})
11144 You would normally leave this field to @code{#f}, initialize user
11145 passwords as @code{root} with the @command{passwd} command, and then let
11146 users change it with @command{passwd}. Passwords set with
11147 @command{passwd} are of course preserved across reboot and
11150 If you @emph{do} want to set an initial password for an account, then
11151 this field must contain the encrypted password, as a string. You can use the
11152 @code{crypt} procedure for this purpose:
11159 ;; Specify a SHA-512-hashed initial password.
11160 (password (crypt "InitialPassword!" "$6$abc")))
11164 The hash of this initial password will be available in a file in
11165 @file{/gnu/store}, readable by all the users, so this method must be used with
11169 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11170 more information on password encryption, and @ref{Encryption,,, guile, GNU
11171 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11177 User group declarations are even simpler:
11180 (user-group (name "students"))
11183 @deftp {Data Type} user-group
11184 This type is for, well, user groups. There are just a few fields:
11188 The name of the group.
11190 @item @code{id} (default: @code{#f})
11191 The group identifier (a number). If @code{#f}, a new number is
11192 automatically allocated when the group is created.
11194 @item @code{system?} (default: @code{#f})
11195 This Boolean value indicates whether the group is a ``system'' group.
11196 System groups have low numerical IDs.
11198 @item @code{password} (default: @code{#f})
11199 What, user groups can have a password? Well, apparently yes. Unless
11200 @code{#f}, this field specifies the password of the group.
11205 For convenience, a variable lists all the basic user groups one may
11208 @defvr {Scheme Variable} %base-groups
11209 This is the list of basic user groups that users and/or packages expect
11210 to be present on the system. This includes groups such as ``root'',
11211 ``wheel'', and ``users'', as well as groups used to control access to
11212 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11215 @defvr {Scheme Variable} %base-user-accounts
11216 This is the list of basic system accounts that programs may expect to
11217 find on a GNU/Linux system, such as the ``nobody'' account.
11219 Note that the ``root'' account is not included here. It is a
11220 special-case and is automatically added whether or not it is specified.
11223 @node Keyboard Layout
11224 @section Keyboard Layout
11226 @cindex keyboard layout
11228 To specify what each key of your keyboard does, you need to tell the operating
11229 system what @dfn{keyboard layout} you want to use. The default, when nothing
11230 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11231 However, German speakers will usually prefer the German QWERTZ layout, French
11232 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11233 or bépo, and they might even want to further customize the effect of some of
11234 the keys. This section explains how to get that done.
11236 @cindex keyboard layout, definition
11237 There are three components that will want to know about your keyboard layout:
11241 The @emph{bootloader} may want to know what keyboard layout you want to use
11242 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11243 you want, for instance, to make sure that you can type the passphrase of your
11244 encrypted root partition using the right layout.
11247 The @emph{operating system kernel}, Linux, will need that so that the console
11248 is properly configured (@pxref{operating-system Reference,
11249 @code{keyboard-layout}}).
11252 The @emph{graphical display server}, usually Xorg, also has its own idea of
11253 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11256 Guix allows you to configure all three separately but, fortunately, it allows
11257 you to share the same keyboard layout for all three components.
11259 @cindex XKB, keyboard layouts
11260 Keyboard layouts are represented by records created by the
11261 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11262 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11263 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11264 optional variant name, an optional keyboard model name, and a possibly empty
11265 list of additional options. In most cases the layout name is all you care
11266 about. Here are a few example:
11269 ;; The German QWERTZ layout. Here we assume a standard
11270 ;; "pc105" keyboard model.
11271 (keyboard-layout "de")
11273 ;; The bépo variant of the French layout.
11274 (keyboard-layout "fr" "bepo")
11276 ;; The Catalan layout.
11277 (keyboard-layout "es" "cat")
11279 ;; The Latin American Spanish layout. In addition, the
11280 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11281 ;; and the "Menu" key is used as a "Compose" key to enter
11282 ;; accented letters.
11283 (keyboard-layout "latam"
11284 #:options '("ctrl:nocaps" "compose:menu"))
11286 ;; The Russian layout for a ThinkPad keyboard.
11287 (keyboard-layout "ru" #:model "thinkpad")
11289 ;; The "US international" layout, which is the US layout plus
11290 ;; dead keys to enter accented characters. This is for an
11291 ;; Apple MacBook keyboard.
11292 (keyboard-layout "us" "intl" #:model "macbook78")
11295 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11296 for a complete list of supported layouts, variants, and models.
11298 @cindex keyboard layout, configuration
11299 Let's say you want your system to use the Turkish keyboard layout throughout
11300 your system---bootloader, console, and Xorg. Here's what your system
11301 configuration would look like:
11303 @findex set-xorg-configuration
11305 ;; Using the Turkish layout for the bootloader, the console,
11310 (keyboard-layout (keyboard-layout "tr")) ;for the console
11311 (bootloader (bootloader-configuration
11312 (bootloader grub-efi-bootloader)
11313 (target "/boot/efi")
11314 (keyboard-layout keyboard-layout))) ;for GRUB
11315 (services (cons (set-xorg-configuration
11316 (xorg-configuration ;for Xorg
11317 (keyboard-layout keyboard-layout)))
11318 %desktop-services)))
11321 In the example above, for GRUB and for Xorg, we just refer to the
11322 @code{keyboard-layout} field defined above, but we could just as well refer to
11323 a different layout. The @code{set-xorg-configuration} procedure communicates
11324 the desired Xorg configuration to the graphical log-in manager, by default
11327 We've discussed how to specify the @emph{default} keyboard layout of your
11328 system when it starts, but you can also adjust it at run time:
11332 If you're using GNOME, its settings panel has a ``Region & Language'' entry
11333 where you can select one or more keyboard layouts.
11336 Under Xorg, the @command{setxkbmap} command (from the same-named package)
11337 allows you to change the current layout. For example, this is how you would
11338 change the layout to US Dvorak:
11341 setxkbmap us dvorak
11345 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
11346 console. However, note that @code{loadkeys} does @emph{not} use the XKB
11347 keyboard layout categorization described above. The command below loads the
11348 French bépo layout:
11359 A @dfn{locale} defines cultural conventions for a particular language
11360 and region of the world (@pxref{Locales,,, libc, The GNU C Library
11361 Reference Manual}). Each locale has a name that typically has the form
11362 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
11363 @code{fr_LU.utf8} designates the locale for the French language, with
11364 cultural conventions from Luxembourg, and using the UTF-8 encoding.
11366 @cindex locale definition
11367 Usually, you will want to specify the default locale for the machine
11368 using the @code{locale} field of the @code{operating-system} declaration
11369 (@pxref{operating-system Reference, @code{locale}}).
11371 The selected locale is automatically added to the @dfn{locale
11372 definitions} known to the system if needed, with its codeset inferred
11373 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
11374 @code{UTF-8} codeset. Additional locale definitions can be specified in
11375 the @code{locale-definitions} slot of @code{operating-system}---this is
11376 useful, for instance, if the codeset could not be inferred from the
11377 locale name. The default set of locale definitions includes some widely
11378 used locales, but not all the available locales, in order to save space.
11380 For instance, to add the North Frisian locale for Germany, the value of
11384 (cons (locale-definition
11385 (name "fy_DE.utf8") (source "fy_DE"))
11386 %default-locale-definitions)
11389 Likewise, to save space, one might want @code{locale-definitions} to
11390 list only the locales that are actually used, as in:
11393 (list (locale-definition
11394 (name "ja_JP.eucjp") (source "ja_JP")
11395 (charset "EUC-JP")))
11399 The compiled locale definitions are available at
11400 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
11401 version, which is the default location where the GNU@tie{}libc provided
11402 by Guix looks for locale data. This can be overridden using the
11403 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
11404 @code{LOCPATH} and locale packages}).
11406 The @code{locale-definition} form is provided by the @code{(gnu system
11407 locale)} module. Details are given below.
11409 @deftp {Data Type} locale-definition
11410 This is the data type of a locale definition.
11415 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
11416 Reference Manual}, for more information on locale names.
11418 @item @code{source}
11419 The name of the source for that locale. This is typically the
11420 @code{@var{language}_@var{territory}} part of the locale name.
11422 @item @code{charset} (default: @code{"UTF-8"})
11423 The ``character set'' or ``code set'' for that locale,
11424 @uref{https://www.iana.org/assignments/character-sets, as defined by
11430 @defvr {Scheme Variable} %default-locale-definitions
11431 A list of commonly used UTF-8 locales, used as the default
11432 value of the @code{locale-definitions} field of @code{operating-system}
11435 @cindex locale name
11436 @cindex normalized codeset in locale names
11437 These locale definitions use the @dfn{normalized codeset} for the part
11438 that follows the dot in the name (@pxref{Using gettextized software,
11439 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
11440 instance it has @code{uk_UA.utf8} but @emph{not}, say,
11441 @code{uk_UA.UTF-8}.
11444 @subsection Locale Data Compatibility Considerations
11446 @cindex incompatibility, of locale data
11447 @code{operating-system} declarations provide a @code{locale-libcs} field
11448 to specify the GNU@tie{}libc packages that are used to compile locale
11449 declarations (@pxref{operating-system Reference}). ``Why would I
11450 care?'', you may ask. Well, it turns out that the binary format of
11451 locale data is occasionally incompatible from one libc version to
11454 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
11455 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
11456 For instance, a program linked against libc version 2.21 is unable to
11457 read locale data produced with libc 2.22; worse, that program
11458 @emph{aborts} instead of simply ignoring the incompatible locale
11459 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
11460 the incompatible locale data, which is already an improvement.}.
11461 Similarly, a program linked against libc 2.22 can read most, but not
11462 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
11463 data is incompatible); thus calls to @code{setlocale} may fail, but
11464 programs will not abort.
11466 The ``problem'' with Guix is that users have a lot of freedom: They can
11467 choose whether and when to upgrade software in their profiles, and might
11468 be using a libc version different from the one the system administrator
11469 used to build the system-wide locale data.
11471 Fortunately, unprivileged users can also install their own locale data
11472 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
11473 @code{GUIX_LOCPATH} and locale packages}).
11475 Still, it is best if the system-wide locale data at
11476 @file{/run/current-system/locale} is built for all the libc versions
11477 actually in use on the system, so that all the programs can access
11478 it---this is especially crucial on a multi-user system. To do that, the
11479 administrator can specify several libc packages in the
11480 @code{locale-libcs} field of @code{operating-system}:
11483 (use-package-modules base)
11487 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
11490 This example would lead to a system containing locale definitions for
11491 both libc 2.21 and the current version of libc in
11492 @file{/run/current-system/locale}.
11498 @cindex system services
11499 An important part of preparing an @code{operating-system} declaration is
11500 listing @dfn{system services} and their configuration (@pxref{Using the
11501 Configuration System}). System services are typically daemons launched
11502 when the system boots, or other actions needed at that time---e.g.,
11503 configuring network access.
11505 Guix has a broad definition of ``service'' (@pxref{Service
11506 Composition}), but many services are managed by the GNU@tie{}Shepherd
11507 (@pxref{Shepherd Services}). On a running system, the @command{herd}
11508 command allows you to list the available services, show their status,
11509 start and stop them, or do other specific operations (@pxref{Jump
11510 Start,,, shepherd, The GNU Shepherd Manual}). For example:
11516 The above command, run as @code{root}, lists the currently defined
11517 services. The @command{herd doc} command shows a synopsis of the given
11518 service and its associated actions:
11522 Run libc's name service cache daemon (nscd).
11524 # herd doc nscd action invalidate
11525 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
11528 The @command{start}, @command{stop}, and @command{restart} sub-commands
11529 have the effect you would expect. For instance, the commands below stop
11530 the nscd service and restart the Xorg display server:
11534 Service nscd has been stopped.
11535 # herd restart xorg-server
11536 Service xorg-server has been stopped.
11537 Service xorg-server has been started.
11540 The following sections document the available services, starting with
11541 the core services, that may be used in an @code{operating-system}
11545 * Base Services:: Essential system services.
11546 * Scheduled Job Execution:: The mcron service.
11547 * Log Rotation:: The rottlog service.
11548 * Networking Services:: Network setup, SSH daemon, etc.
11549 * X Window:: Graphical display.
11550 * Printing Services:: Local and remote printer support.
11551 * Desktop Services:: D-Bus and desktop services.
11552 * Sound Services:: ALSA and Pulseaudio services.
11553 * Database Services:: SQL databases, key-value stores, etc.
11554 * Mail Services:: IMAP, POP3, SMTP, and all that.
11555 * Messaging Services:: Messaging services.
11556 * Telephony Services:: Telephony services.
11557 * Monitoring Services:: Monitoring services.
11558 * Kerberos Services:: Kerberos services.
11559 * LDAP Services:: LDAP services.
11560 * Web Services:: Web servers.
11561 * Certificate Services:: TLS certificates via Let's Encrypt.
11562 * DNS Services:: DNS daemons.
11563 * VPN Services:: VPN daemons.
11564 * Network File System:: NFS related services.
11565 * Continuous Integration:: The Cuirass service.
11566 * Power Management Services:: Extending battery life.
11567 * Audio Services:: The MPD.
11568 * Virtualization Services:: Virtualization services.
11569 * Version Control Services:: Providing remote access to Git repositories.
11570 * Game Services:: Game servers.
11571 * Miscellaneous Services:: Other services.
11574 @node Base Services
11575 @subsection Base Services
11577 The @code{(gnu services base)} module provides definitions for the basic
11578 services that one expects from the system. The services exported by
11579 this module are listed below.
11581 @defvr {Scheme Variable} %base-services
11582 This variable contains a list of basic services (@pxref{Service Types
11583 and Services}, for more information on service objects) one would
11584 expect from the system: a login service (mingetty) on each tty, syslogd,
11585 the libc name service cache daemon (nscd), the udev device manager, and
11588 This is the default value of the @code{services} field of
11589 @code{operating-system} declarations. Usually, when customizing a
11590 system, you will want to append services to @code{%base-services}, like
11594 (append (list (service avahi-service-type)
11595 (service openssh-service-type))
11600 @defvr {Scheme Variable} special-files-service-type
11601 This is the service that sets up ``special files'' such as
11602 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
11604 The value associated with @code{special-files-service-type} services
11605 must be a list of tuples where the first element is the ``special file''
11606 and the second element is its target. By default it is:
11608 @cindex @file{/bin/sh}
11609 @cindex @file{sh}, in @file{/bin}
11611 `(("/bin/sh" ,(file-append @var{bash} "/bin/sh")))
11614 @cindex @file{/usr/bin/env}
11615 @cindex @file{env}, in @file{/usr/bin}
11616 If you want to add, say, @code{/usr/bin/env} to your system, you can
11620 `(("/bin/sh" ,(file-append @var{bash} "/bin/sh"))
11621 ("/usr/bin/env" ,(file-append @var{coreutils} "/bin/env")))
11624 Since this is part of @code{%base-services}, you can use
11625 @code{modify-services} to customize the set of special files
11626 (@pxref{Service Reference, @code{modify-services}}). But the simple way
11627 to add a special file is @i{via} the @code{extra-special-file} procedure
11631 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
11632 Use @var{target} as the ``special file'' @var{file}.
11634 For example, adding the following lines to the @code{services} field of
11635 your operating system declaration leads to a @file{/usr/bin/env}
11639 (extra-special-file "/usr/bin/env"
11640 (file-append coreutils "/bin/env"))
11644 @deffn {Scheme Procedure} host-name-service @var{name}
11645 Return a service that sets the host name to @var{name}.
11648 @deffn {Scheme Procedure} login-service @var{config}
11649 Return a service to run login according to @var{config}, a
11650 @code{<login-configuration>} object, which specifies the message of the day,
11651 among other things.
11654 @deftp {Data Type} login-configuration
11655 This is the data type representing the configuration of login.
11660 @cindex message of the day
11661 A file-like object containing the ``message of the day''.
11663 @item @code{allow-empty-passwords?} (default: @code{#t})
11664 Allow empty passwords by default so that first-time users can log in when
11665 the 'root' account has just been created.
11670 @deffn {Scheme Procedure} mingetty-service @var{config}
11671 Return a service to run mingetty according to @var{config}, a
11672 @code{<mingetty-configuration>} object, which specifies the tty to run, among
11676 @deftp {Data Type} mingetty-configuration
11677 This is the data type representing the configuration of Mingetty, which
11678 provides the default implementation of virtual console log-in.
11683 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
11685 @item @code{auto-login} (default: @code{#f})
11686 When true, this field must be a string denoting the user name under
11687 which the system automatically logs in. When it is @code{#f}, a
11688 user name and password must be entered to log in.
11690 @item @code{login-program} (default: @code{#f})
11691 This must be either @code{#f}, in which case the default log-in program
11692 is used (@command{login} from the Shadow tool suite), or a gexp denoting
11693 the name of the log-in program.
11695 @item @code{login-pause?} (default: @code{#f})
11696 When set to @code{#t} in conjunction with @var{auto-login}, the user
11697 will have to press a key before the log-in shell is launched.
11699 @item @code{mingetty} (default: @var{mingetty})
11700 The Mingetty package to use.
11705 @deffn {Scheme Procedure} agetty-service @var{config}
11706 Return a service to run agetty according to @var{config}, an
11707 @code{<agetty-configuration>} object, which specifies the tty to run,
11708 among other things.
11711 @deftp {Data Type} agetty-configuration
11712 This is the data type representing the configuration of agetty, which
11713 implements virtual and serial console log-in. See the @code{agetty(8)}
11714 man page for more information.
11719 The name of the console this agetty runs on, as a string---e.g.,
11720 @code{"ttyS0"}. This argument is optional, it will default to
11721 a reasonable default serial port used by the kernel Linux.
11723 For this, if there is a value for an option @code{agetty.tty} in the kernel
11724 command line, agetty will extract the device name of the serial port
11725 from it and use that.
11727 If not and if there is a value for an option @code{console} with a tty in
11728 the Linux command line, agetty will extract the device name of the
11729 serial port from it and use that.
11731 In both cases, agetty will leave the other serial device settings
11732 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
11735 @item @code{baud-rate} (default: @code{#f})
11736 A string containing a comma-separated list of one or more baud rates, in
11739 @item @code{term} (default: @code{#f})
11740 A string containing the value used for the @code{TERM} environment
11743 @item @code{eight-bits?} (default: @code{#f})
11744 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
11747 @item @code{auto-login} (default: @code{#f})
11748 When passed a login name, as a string, the specified user will be logged
11749 in automatically without prompting for their login name or password.
11751 @item @code{no-reset?} (default: @code{#f})
11752 When @code{#t}, don't reset terminal cflags (control modes).
11754 @item @code{host} (default: @code{#f})
11755 This accepts a string containing the "login_host", which will be written
11756 into the @file{/var/run/utmpx} file.
11758 @item @code{remote?} (default: @code{#f})
11759 When set to @code{#t} in conjunction with @var{host}, this will add an
11760 @code{-r} fakehost option to the command line of the login program
11761 specified in @var{login-program}.
11763 @item @code{flow-control?} (default: @code{#f})
11764 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
11766 @item @code{no-issue?} (default: @code{#f})
11767 When set to @code{#t}, the contents of the @file{/etc/issue} file will
11768 not be displayed before presenting the login prompt.
11770 @item @code{init-string} (default: @code{#f})
11771 This accepts a string that will be sent to the tty or modem before
11772 sending anything else. It can be used to initialize a modem.
11774 @item @code{no-clear?} (default: @code{#f})
11775 When set to @code{#t}, agetty will not clear the screen before showing
11778 @item @code{login-program} (default: (file-append shadow "/bin/login"))
11779 This must be either a gexp denoting the name of a log-in program, or
11780 unset, in which case the default value is the @command{login} from the
11783 @item @code{local-line} (default: @code{#f})
11784 Control the CLOCAL line flag. This accepts one of three symbols as
11785 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
11786 the default value chosen by agetty is @code{'auto}.
11788 @item @code{extract-baud?} (default: @code{#f})
11789 When set to @code{#t}, instruct agetty to try to extract the baud rate
11790 from the status messages produced by certain types of modems.
11792 @item @code{skip-login?} (default: @code{#f})
11793 When set to @code{#t}, do not prompt the user for a login name. This
11794 can be used with @var{login-program} field to use non-standard login
11797 @item @code{no-newline?} (default: @code{#f})
11798 When set to @code{#t}, do not print a newline before printing the
11799 @file{/etc/issue} file.
11801 @c Is this dangerous only when used with login-program, or always?
11802 @item @code{login-options} (default: @code{#f})
11803 This option accepts a string containing options that are passed to the
11804 login program. When used with the @var{login-program}, be aware that a
11805 malicious user could try to enter a login name containing embedded
11806 options that could be parsed by the login program.
11808 @item @code{login-pause} (default: @code{#f})
11809 When set to @code{#t}, wait for any key before showing the login prompt.
11810 This can be used in conjunction with @var{auto-login} to save memory by
11811 lazily spawning shells.
11813 @item @code{chroot} (default: @code{#f})
11814 Change root to the specified directory. This option accepts a directory
11817 @item @code{hangup?} (default: @code{#f})
11818 Use the Linux system call @code{vhangup} to do a virtual hangup of the
11819 specified terminal.
11821 @item @code{keep-baud?} (default: @code{#f})
11822 When set to @code{#t}, try to keep the existing baud rate. The baud
11823 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
11826 @item @code{timeout} (default: @code{#f})
11827 When set to an integer value, terminate if no user name could be read
11828 within @var{timeout} seconds.
11830 @item @code{detect-case?} (default: @code{#f})
11831 When set to @code{#t}, turn on support for detecting an uppercase-only
11832 terminal. This setting will detect a login name containing only
11833 uppercase letters as indicating an uppercase-only terminal and turn on
11834 some upper-to-lower case conversions. Note that this will not support
11835 Unicode characters.
11837 @item @code{wait-cr?} (default: @code{#f})
11838 When set to @code{#t}, wait for the user or modem to send a
11839 carriage-return or linefeed character before displaying
11840 @file{/etc/issue} or login prompt. This is typically used with the
11841 @var{init-string} option.
11843 @item @code{no-hints?} (default: @code{#f})
11844 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
11847 @item @code{no-hostname?} (default: @code{#f})
11848 By default, the hostname is printed. When this option is set to
11849 @code{#t}, no hostname will be shown at all.
11851 @item @code{long-hostname?} (default: @code{#f})
11852 By default, the hostname is only printed until the first dot. When this
11853 option is set to @code{#t}, the fully qualified hostname by
11854 @code{gethostname} or @code{getaddrinfo} is shown.
11856 @item @code{erase-characters} (default: @code{#f})
11857 This option accepts a string of additional characters that should be
11858 interpreted as backspace when the user types their login name.
11860 @item @code{kill-characters} (default: @code{#f})
11861 This option accepts a string that should be interpreted to mean "ignore
11862 all previous characters" (also called a "kill" character) when the user
11863 types their login name.
11865 @item @code{chdir} (default: @code{#f})
11866 This option accepts, as a string, a directory path that will be changed
11869 @item @code{delay} (default: @code{#f})
11870 This options accepts, as an integer, the number of seconds to sleep
11871 before opening the tty and displaying the login prompt.
11873 @item @code{nice} (default: @code{#f})
11874 This option accepts, as an integer, the nice value with which to run the
11875 @command{login} program.
11877 @item @code{extra-options} (default: @code{'()})
11878 This option provides an "escape hatch" for the user to provide arbitrary
11879 command-line arguments to @command{agetty} as a list of strings.
11884 @deffn {Scheme Procedure} kmscon-service-type @var{config}
11885 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
11886 according to @var{config}, a @code{<kmscon-configuration>} object, which
11887 specifies the tty to run, among other things.
11890 @deftp {Data Type} kmscon-configuration
11891 This is the data type representing the configuration of Kmscon, which
11892 implements virtual console log-in.
11896 @item @code{virtual-terminal}
11897 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
11899 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
11900 A gexp denoting the name of the log-in program. The default log-in program is
11901 @command{login} from the Shadow tool suite.
11903 @item @code{login-arguments} (default: @code{'("-p")})
11904 A list of arguments to pass to @command{login}.
11906 @item @code{auto-login} (default: @code{#f})
11907 When passed a login name, as a string, the specified user will be logged
11908 in automatically without prompting for their login name or password.
11910 @item @code{hardware-acceleration?} (default: #f)
11911 Whether to use hardware acceleration.
11913 @item @code{kmscon} (default: @var{kmscon})
11914 The Kmscon package to use.
11919 @cindex name service cache daemon
11921 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
11922 [#:name-services '()]
11923 Return a service that runs the libc name service cache daemon (nscd) with the
11924 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
11925 Service Switch}, for an example.
11927 For convenience, the Shepherd service for nscd provides the following actions:
11931 @cindex cache invalidation, nscd
11932 @cindex nscd, cache invalidation
11933 This invalidate the given cache. For instance, running:
11936 herd invalidate nscd hosts
11940 invalidates the host name lookup cache of nscd.
11943 Running @command{herd statistics nscd} displays information about nscd usage
11949 @defvr {Scheme Variable} %nscd-default-configuration
11950 This is the default @code{<nscd-configuration>} value (see below) used
11951 by @code{nscd-service}. It uses the caches defined by
11952 @var{%nscd-default-caches}; see below.
11955 @deftp {Data Type} nscd-configuration
11956 This is the data type representing the name service cache daemon (nscd)
11961 @item @code{name-services} (default: @code{'()})
11962 List of packages denoting @dfn{name services} that must be visible to
11963 the nscd---e.g., @code{(list @var{nss-mdns})}.
11965 @item @code{glibc} (default: @var{glibc})
11966 Package object denoting the GNU C Library providing the @command{nscd}
11969 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
11970 Name of the nscd log file. This is where debugging output goes when
11971 @code{debug-level} is strictly positive.
11973 @item @code{debug-level} (default: @code{0})
11974 Integer denoting the debugging levels. Higher numbers mean that more
11975 debugging output is logged.
11977 @item @code{caches} (default: @var{%nscd-default-caches})
11978 List of @code{<nscd-cache>} objects denoting things to be cached; see
11984 @deftp {Data Type} nscd-cache
11985 Data type representing a cache database of nscd and its parameters.
11989 @item @code{database}
11990 This is a symbol representing the name of the database to be cached.
11991 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
11992 @code{services}, which designate the corresponding NSS database
11993 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
11995 @item @code{positive-time-to-live}
11996 @itemx @code{negative-time-to-live} (default: @code{20})
11997 A number representing the number of seconds during which a positive or
11998 negative lookup result remains in cache.
12000 @item @code{check-files?} (default: @code{#t})
12001 Whether to check for updates of the files corresponding to
12004 For instance, when @var{database} is @code{hosts}, setting this flag
12005 instructs nscd to check for updates in @file{/etc/hosts} and to take
12008 @item @code{persistent?} (default: @code{#t})
12009 Whether the cache should be stored persistently on disk.
12011 @item @code{shared?} (default: @code{#t})
12012 Whether the cache should be shared among users.
12014 @item @code{max-database-size} (default: 32@tie{}MiB)
12015 Maximum size in bytes of the database cache.
12017 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
12018 @c settings, so leave them out.
12023 @defvr {Scheme Variable} %nscd-default-caches
12024 List of @code{<nscd-cache>} objects used by default by
12025 @code{nscd-configuration} (see above).
12027 It enables persistent and aggressive caching of service and host name
12028 lookups. The latter provides better host name lookup performance,
12029 resilience in the face of unreliable name servers, and also better
12030 privacy---often the result of host name lookups is in local cache, so
12031 external name servers do not even need to be queried.
12034 @anchor{syslog-configuration-type}
12037 @deftp {Data Type} syslog-configuration
12038 This data type represents the configuration of the syslog daemon.
12041 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12042 The syslog daemon to use.
12044 @item @code{config-file} (default: @code{%default-syslog.conf})
12045 The syslog configuration file to use.
12050 @anchor{syslog-service}
12052 @deffn {Scheme Procedure} syslog-service @var{config}
12053 Return a service that runs a syslog daemon according to @var{config}.
12055 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12056 information on the configuration file syntax.
12059 @defvr {Scheme Variable} guix-service-type
12060 This is the type of the service that runs the build daemon,
12061 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12062 @code{guix-configuration} record as described below.
12065 @anchor{guix-configuration-type}
12066 @deftp {Data Type} guix-configuration
12067 This data type represents the configuration of the Guix build daemon.
12068 @xref{Invoking guix-daemon}, for more information.
12071 @item @code{guix} (default: @var{guix})
12072 The Guix package to use.
12074 @item @code{build-group} (default: @code{"guixbuild"})
12075 Name of the group for build user accounts.
12077 @item @code{build-accounts} (default: @code{10})
12078 Number of build user accounts to create.
12080 @item @code{authorize-key?} (default: @code{#t})
12081 @cindex substitutes, authorization thereof
12082 Whether to authorize the substitute keys listed in
12083 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12084 (@pxref{Substitutes}).
12086 @vindex %default-authorized-guix-keys
12087 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12088 The list of authorized key files for archive imports, as a list of
12089 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12090 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12092 @item @code{use-substitutes?} (default: @code{#t})
12093 Whether to use substitutes.
12095 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12096 The list of URLs where to look for substitutes by default.
12098 @item @code{max-silent-time} (default: @code{0})
12099 @itemx @code{timeout} (default: @code{0})
12100 The number of seconds of silence and the number of seconds of activity,
12101 respectively, after which a build process times out. A value of zero
12102 disables the timeout.
12104 @item @code{log-compression} (default: @code{'bzip2})
12105 The type of compression used for build logs---one of @code{gzip},
12106 @code{bzip2}, or @code{none}.
12108 @item @code{extra-options} (default: @code{'()})
12109 List of extra command-line options for @command{guix-daemon}.
12111 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12112 File where @command{guix-daemon}'s standard output and standard error
12115 @item @code{http-proxy} (default: @code{#f})
12116 The HTTP proxy used for downloading fixed-output derivations and
12119 @item @code{tmpdir} (default: @code{#f})
12120 A directory path where the @command{guix-daemon} will perform builds.
12125 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12126 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12127 udev rules can be provided as a list of files through the @var{rules}
12128 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12129 @code{(gnu services base)} simplify the creation of such rule files.
12132 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12133 Return a udev-rule file named @var{file-name} containing the rules
12134 defined by the @var{contents} literal.
12136 In the following example, a rule for a USB device is defined to be
12137 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12138 upon detecting a USB device with a given product identifier.
12141 (define %example-udev-rule
12143 "90-usb-thing.rules"
12144 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12145 "ATTR@{product@}==\"Example\", "
12146 "RUN+=\"/path/to/script\"")))
12149 The @command{herd rules udev} command, as root, returns the name of the
12150 directory containing all the active udev rules.
12153 Here we show how the default @var{udev-service} can be extended with it.
12159 (modify-services %desktop-services
12160 (udev-service-type config =>
12161 (udev-configuration (inherit config)
12162 (rules (append (udev-configuration-rules config)
12163 (list %example-udev-rule))))))))
12166 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12167 Return a udev file named @var{file-name} containing the rules defined
12168 within @var{file}, a file-like object.
12170 The following example showcases how we can use an existing rule file.
12173 (use-modules (guix download) ;for url-fetch
12174 (guix packages) ;for origin
12177 (define %android-udev-rules
12179 "51-android-udev.rules"
12180 (let ((version "20170910"))
12183 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12184 "android-udev-rules/" version "/51-android.rules"))
12186 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12190 Additionally, Guix package definitions can be included in @var{rules} in
12191 order to extend the udev rules with the definitions found under their
12192 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12193 @var{file->udev-rule} example, we could have used the
12194 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12195 packages android)} module.
12197 The following example shows how to use the @var{android-udev-rules}
12198 package so that the Android tool @command{adb} can detect devices
12199 without root privileges. It also details how to create the
12200 @code{adbusers} group, which is required for the proper functioning of
12201 the rules defined within the @var{android-udev-rules} package. To
12202 create such a group, we must define it both as part of the
12203 @var{supplementary-groups} of our @var{user-account} declaration, as
12204 well as in the @var{groups} field of the @var{operating-system} record.
12207 (use-modules (gnu packages android) ;for android-udev-rules
12208 (gnu system shadow) ;for user-group
12213 (users (cons (user-acount
12215 (supplementary-groups
12216 '("adbusers" ;for adb
12217 "wheel" "netdev" "audio" "video"))
12220 (groups (cons (user-group (system? #t) (name "adbusers"))
12226 (modify-services %desktop-services
12229 (udev-configuration (inherit config)
12230 (rules (cons android-udev-rules
12231 (udev-configuration-rules config))))))))
12234 @defvr {Scheme Variable} urandom-seed-service-type
12235 Save some entropy in @var{%random-seed-file} to seed @file{/dev/urandom}
12236 when rebooting. It also tries to seed @file{/dev/urandom} from
12237 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12241 @defvr {Scheme Variable} %random-seed-file
12242 This is the name of the file where some random bytes are saved by
12243 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12244 It defaults to @file{/var/lib/random-seed}.
12249 @defvr {Scheme Variable} gpm-service-type
12250 This is the type of the service that runs GPM, the @dfn{general-purpose
12251 mouse daemon}, which provides mouse support to the Linux console. GPM
12252 allows users to use the mouse in the console, notably to select, copy,
12255 The value for services of this type must be a @code{gpm-configuration}
12256 (see below). This service is not part of @code{%base-services}.
12259 @deftp {Data Type} gpm-configuration
12260 Data type representing the configuration of GPM.
12263 @item @code{options} (default: @code{%default-gpm-options})
12264 Command-line options passed to @command{gpm}. The default set of
12265 options instruct @command{gpm} to listen to mouse events on
12266 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12269 @item @code{gpm} (default: @code{gpm})
12270 The GPM package to use.
12275 @anchor{guix-publish-service-type}
12276 @deffn {Scheme Variable} guix-publish-service-type
12277 This is the service type for @command{guix publish} (@pxref{Invoking
12278 guix publish}). Its value must be a @code{guix-publish-configuration}
12279 object, as described below.
12281 This assumes that @file{/etc/guix} already contains a signing key pair as
12282 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12283 archive}). If that is not the case, the service will fail to start.
12286 @deftp {Data Type} guix-publish-configuration
12287 Data type representing the configuration of the @code{guix publish}
12291 @item @code{guix} (default: @code{guix})
12292 The Guix package to use.
12294 @item @code{port} (default: @code{80})
12295 The TCP port to listen for connections.
12297 @item @code{host} (default: @code{"localhost"})
12298 The host (and thus, network interface) to listen to. Use
12299 @code{"0.0.0.0"} to listen on all the network interfaces.
12301 @item @code{compression} (default: @code{'(("gzip" 3))})
12302 This is a list of compression method/level tuple used when compressing
12303 substitutes. For example, to compress all substitutes with @emph{both} lzip
12304 at level 7 and gzip at level 9, write:
12307 '(("lzip" 7) ("gzip" 9))
12310 Level 9 achieves the best compression ratio at the expense of increased CPU
12311 usage, whereas level 1 achieves fast compression.
12313 An empty list disables compression altogether.
12315 @item @code{nar-path} (default: @code{"nar"})
12316 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
12317 publish, @code{--nar-path}}, for details.
12319 @item @code{cache} (default: @code{#f})
12320 When it is @code{#f}, disable caching and instead generate archives on
12321 demand. Otherwise, this should be the name of a directory---e.g.,
12322 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
12323 archives and meta-data ready to be sent. @xref{Invoking guix publish,
12324 @option{--cache}}, for more information on the tradeoffs involved.
12326 @item @code{workers} (default: @code{#f})
12327 When it is an integer, this is the number of worker threads used for
12328 caching; when @code{#f}, the number of processors is used.
12329 @xref{Invoking guix publish, @option{--workers}}, for more information.
12331 @item @code{ttl} (default: @code{#f})
12332 When it is an integer, this denotes the @dfn{time-to-live} in seconds
12333 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
12334 for more information.
12338 @anchor{rngd-service}
12339 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
12340 [#:device "/dev/hwrng"]
12341 Return a service that runs the @command{rngd} program from @var{rng-tools}
12342 to add @var{device} to the kernel's entropy pool. The service will fail if
12343 @var{device} does not exist.
12346 @anchor{pam-limits-service}
12347 @cindex session limits
12352 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
12354 Return a service that installs a configuration file for the
12355 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
12356 @code{pam_limits} module}. The procedure optionally takes a list of
12357 @code{pam-limits-entry} values, which can be used to specify
12358 @code{ulimit} limits and nice priority limits to user sessions.
12360 The following limits definition sets two hard and soft limits for all
12361 login sessions of users in the @code{realtime} group:
12364 (pam-limits-service
12366 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
12367 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
12370 The first entry increases the maximum realtime priority for
12371 non-privileged processes; the second entry lifts any restriction of the
12372 maximum address space that can be locked in memory. These settings are
12373 commonly used for real-time audio systems.
12376 @node Scheduled Job Execution
12377 @subsection Scheduled Job Execution
12381 @cindex scheduling jobs
12382 The @code{(gnu services mcron)} module provides an interface to
12383 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
12384 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
12385 Unix @command{cron} daemon; the main difference is that it is
12386 implemented in Guile Scheme, which provides a lot of flexibility when
12387 specifying the scheduling of jobs and their actions.
12389 The example below defines an operating system that runs the
12390 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
12391 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
12392 well as the @command{mkid} command on behalf of an unprivileged user
12393 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
12394 gexps to introduce job definitions that are passed to mcron
12395 (@pxref{G-Expressions}).
12398 (use-modules (guix) (gnu) (gnu services mcron))
12399 (use-package-modules base idutils)
12401 (define updatedb-job
12402 ;; Run 'updatedb' at 3AM every day. Here we write the
12403 ;; job's action as a Scheme procedure.
12404 #~(job '(next-hour '(3))
12406 (execl (string-append #$findutils "/bin/updatedb")
12408 "--prunepaths=/tmp /var/tmp /gnu/store"))))
12410 (define garbage-collector-job
12411 ;; Collect garbage 5 minutes after midnight every day.
12412 ;; The job's action is a shell command.
12413 #~(job "5 0 * * *" ;Vixie cron syntax
12416 (define idutils-job
12417 ;; Update the index database as user "charlie" at 12:15PM
12418 ;; and 19:15PM. This runs from the user's home directory.
12419 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
12420 (string-append #$idutils "/bin/mkid src")
12425 (services (cons (service mcron-service-type
12426 (mcron-configuration
12427 (jobs (list garbage-collector-job
12433 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
12434 for more information on mcron job specifications. Below is the
12435 reference of the mcron service.
12437 On a running system, you can use the @code{schedule} action of the service to
12438 visualize the mcron jobs that will be executed next:
12441 # herd schedule mcron
12445 The example above lists the next five tasks that will be executed, but you can
12446 also specify the number of tasks to display:
12449 # herd schedule mcron 10
12452 @defvr {Scheme Variable} mcron-service-type
12453 This is the type of the @code{mcron} service, whose value is an
12454 @code{mcron-configuration} object.
12456 This service type can be the target of a service extension that provides
12457 it additional job specifications (@pxref{Service Composition}). In
12458 other words, it is possible to define services that provide additional
12462 @deftp {Data Type} mcron-configuration
12463 Data type representing the configuration of mcron.
12466 @item @code{mcron} (default: @var{mcron})
12467 The mcron package to use.
12470 This is a list of gexps (@pxref{G-Expressions}), where each gexp
12471 corresponds to an mcron job specification (@pxref{Syntax, mcron job
12472 specifications,, mcron, GNU@tie{}mcron}).
12478 @subsection Log Rotation
12481 @cindex log rotation
12483 Log files such as those found in @file{/var/log} tend to grow endlessly,
12484 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
12485 their contents in separate files, possibly compressed. The @code{(gnu
12486 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
12487 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
12489 The example below defines an operating system that provides log rotation
12490 with the default settings, for commonly encountered log files.
12493 (use-modules (guix) (gnu))
12494 (use-service-modules admin mcron)
12495 (use-package-modules base idutils)
12499 (services (cons (service rottlog-service-type)
12503 @defvr {Scheme Variable} rottlog-service-type
12504 This is the type of the Rottlog service, whose value is a
12505 @code{rottlog-configuration} object.
12507 Other services can extend this one with new @code{log-rotation} objects
12508 (see below), thereby augmenting the set of files to be rotated.
12510 This service type can define mcron jobs (@pxref{Scheduled Job
12511 Execution}) to run the rottlog service.
12514 @deftp {Data Type} rottlog-configuration
12515 Data type representing the configuration of rottlog.
12518 @item @code{rottlog} (default: @code{rottlog})
12519 The Rottlog package to use.
12521 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
12522 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
12523 rottlog, GNU Rot[t]log Manual}).
12525 @item @code{rotations} (default: @code{%default-rotations})
12526 A list of @code{log-rotation} objects as defined below.
12529 This is a list of gexps where each gexp corresponds to an mcron job
12530 specification (@pxref{Scheduled Job Execution}).
12534 @deftp {Data Type} log-rotation
12535 Data type representing the rotation of a group of log files.
12537 Taking an example from the Rottlog manual (@pxref{Period Related File
12538 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
12544 (files '("/var/log/apache/*"))
12545 (options '("storedir apache-archives"
12551 The list of fields is as follows:
12554 @item @code{frequency} (default: @code{'weekly})
12555 The log rotation frequency, a symbol.
12558 The list of files or file glob patterns to rotate.
12560 @item @code{options} (default: @code{'()})
12561 The list of rottlog options for this rotation (@pxref{Configuration
12562 parameters,,, rottlog, GNU Rot[t]lg Manual}).
12564 @item @code{post-rotate} (default: @code{#f})
12565 Either @code{#f} or a gexp to execute once the rotation has completed.
12569 @defvr {Scheme Variable} %default-rotations
12570 Specifies weekly rotation of @var{%rotated-files} and
12571 a couple of other files.
12574 @defvr {Scheme Variable} %rotated-files
12575 The list of syslog-controlled files to be rotated. By default it is:
12576 @code{'("/var/log/messages" "/var/log/secure")}.
12579 @node Networking Services
12580 @subsection Networking Services
12582 The @code{(gnu services networking)} module provides services to configure
12583 the network interface.
12585 @cindex DHCP, networking service
12586 @defvr {Scheme Variable} dhcp-client-service-type
12587 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
12588 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
12589 is the DHCP client package to use, @code{isc-dhcp} by default.
12592 @deffn {Scheme Procedure} dhcpd-service-type
12593 This type defines a service that runs a DHCP daemon. To create a
12594 service of this type, you must supply a @code{<dhcpd-configuration>}.
12598 (service dhcpd-service-type
12599 (dhcpd-configuration
12600 (config-file (local-file "my-dhcpd.conf"))
12601 (interfaces '("enp0s25"))))
12605 @deftp {Data Type} dhcpd-configuration
12607 @item @code{package} (default: @code{isc-dhcp})
12608 The package that provides the DHCP daemon. This package is expected to
12609 provide the daemon at @file{sbin/dhcpd} relative to its output
12610 directory. The default package is the
12611 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
12612 @item @code{config-file} (default: @code{#f})
12613 The configuration file to use. This is required. It will be passed to
12614 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
12615 object (@pxref{G-Expressions, file-like objects}). See @code{man
12616 dhcpd.conf} for details on the configuration file syntax.
12617 @item @code{version} (default: @code{"4"})
12618 The DHCP version to use. The ISC DHCP server supports the values ``4'',
12619 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
12620 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
12622 @item @code{run-directory} (default: @code{"/run/dhcpd"})
12623 The run directory to use. At service activation time, this directory
12624 will be created if it does not exist.
12625 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
12626 The PID file to use. This corresponds to the @code{-pf} option of
12627 @code{dhcpd}. See @code{man dhcpd} for details.
12628 @item @code{interfaces} (default: @code{'()})
12629 The names of the network interfaces on which dhcpd should listen for
12630 broadcasts. If this list is not empty, then its elements (which must be
12631 strings) will be appended to the @code{dhcpd} invocation when starting
12632 the daemon. It may not be necessary to explicitly specify any
12633 interfaces here; see @code{man dhcpd} for details.
12637 @defvr {Scheme Variable} static-networking-service-type
12638 This is the type for statically-configured network interfaces.
12639 @c TODO Document <static-networking> data structures.
12642 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
12643 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
12644 [#:requirement @code{'(udev)}]
12645 Return a service that starts @var{interface} with address @var{ip}. If
12646 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
12647 it must be a string specifying the default network gateway. @var{requirement}
12648 can be used to declare a dependency on another service before configuring the
12651 This procedure can be called several times, one for each network
12652 interface of interest. Behind the scenes what it does is extend
12653 @code{static-networking-service-type} with additional network interfaces
12659 (static-networking-service "eno1" "192.168.1.82"
12660 #:gateway "192.168.1.2"
12661 #:name-servers '("192.168.1.2"))
12668 @cindex network management
12669 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
12670 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
12671 management daemon that aims to simplify wired and wireless networking.
12673 This service adds the @var{wicd} package to the global profile, providing
12674 several commands to interact with the daemon and configure networking:
12675 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
12676 and @command{wicd-curses} user interfaces.
12679 @cindex ModemManager
12681 @defvr {Scheme Variable} modem-manager-service-type
12682 This is the service type for the
12683 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
12684 service. The value for this service type is a
12685 @code{modem-manager-configuration} record.
12687 This service is part of @code{%desktop-services} (@pxref{Desktop
12691 @deftp {Data Type} modem-manager-configuration
12692 Data type representing the configuration of ModemManager.
12695 @item @code{modem-manager} (default: @code{modem-manager})
12696 The ModemManager package to use.
12701 @cindex USB_ModeSwitch
12702 @cindex Modeswitching
12704 @defvr {Scheme Variable} usb-modeswitch-service-type
12705 This is the service type for the
12706 @uref{http://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
12707 value for this service type is a @code{usb-modeswitch-configuration} record.
12709 When plugged in, some USB modems (and other USB devices) initially present
12710 themselves as a read-only storage medium and not as a modem. They need to be
12711 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
12712 installs udev rules to automatically modeswitch these devices when they are
12715 This service is part of @code{%desktop-services} (@pxref{Desktop
12719 @deftp {Data Type} usb-modeswitch-configuration
12720 Data type representing the configuration of USB_ModeSwitch.
12723 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
12724 The USB_ModeSwitch package providing the binaries for modeswitching.
12726 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
12727 The package providing the device data and udev rules file used by
12730 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
12731 Which config file to use for the USB_ModeSwitch dispatcher. By default the
12732 config file shipped with USB_ModeSwitch is used which disables logging to
12733 @file{/var/log} among other default settings. If set to @code{#f}, no config
12739 @cindex NetworkManager
12741 @defvr {Scheme Variable} network-manager-service-type
12742 This is the service type for the
12743 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
12744 service. The value for this service type is a
12745 @code{network-manager-configuration} record.
12747 This service is part of @code{%desktop-services} (@pxref{Desktop
12751 @deftp {Data Type} network-manager-configuration
12752 Data type representing the configuration of NetworkManager.
12755 @item @code{network-manager} (default: @code{network-manager})
12756 The NetworkManager package to use.
12758 @item @code{dns} (default: @code{"default"})
12759 Processing mode for DNS, which affects how NetworkManager uses the
12760 @code{resolv.conf} configuration file.
12764 NetworkManager will update @code{resolv.conf} to reflect the nameservers
12765 provided by currently active connections.
12768 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
12769 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
12770 then update @code{resolv.conf} to point to the local nameserver.
12772 With this setting, you can share your network connection. For example when
12773 you want to share your network connection to another laptop @i{via} an
12774 Ethernet cable, you can open @command{nm-connection-editor} and configure the
12775 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
12776 and reestablish the connection (or reboot).
12778 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
12779 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
12780 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
12781 browser on your host system, or connect to the VM @i{via} SSH
12782 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
12783 host-to-guest connection, run this command once:
12786 nmcli connection add type tun \
12787 connection.interface-name tap0 \
12788 tun.mode tap tun.owner $(id -u) \
12789 ipv4.method shared \
12790 ipv4.addresses 172.28.112.1/24
12793 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
12794 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
12795 @command{qemu-system-...}.
12798 NetworkManager will not modify @code{resolv.conf}.
12801 @item @code{vpn-plugins} (default: @code{'()})
12802 This is the list of available plugins for virtual private networks
12803 (VPNs). An example of this is the @code{network-manager-openvpn}
12804 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
12810 @deffn {Scheme Variable} connman-service-type
12811 This is the service type to run @url{https://01.org/connman,Connman},
12812 a network connection manager.
12814 Its value must be an
12815 @code{connman-configuration} record as in this example:
12818 (service connman-service-type
12819 (connman-configuration
12820 (disable-vpn? #t)))
12823 See below for details about @code{connman-configuration}.
12826 @deftp {Data Type} connman-configuration
12827 Data Type representing the configuration of connman.
12830 @item @code{connman} (default: @var{connman})
12831 The connman package to use.
12833 @item @code{disable-vpn?} (default: @code{#f})
12834 When true, disable connman's vpn plugin.
12838 @cindex WPA Supplicant
12839 @defvr {Scheme Variable} wpa-supplicant-service-type
12840 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
12841 supplicant}, an authentication daemon required to authenticate against
12842 encrypted WiFi or ethernet networks.
12845 @deftp {Data Type} wpa-supplicant-configuration
12846 Data type representing the configuration of WPA Supplicant.
12848 It takes the following parameters:
12851 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
12852 The WPA Supplicant package to use.
12854 @item @code{dbus?} (default: @code{#t})
12855 Whether to listen for requests on D-Bus.
12857 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
12858 Where to store the PID file.
12860 @item @code{interface} (default: @code{#f})
12861 If this is set, it must specify the name of a network interface that
12862 WPA supplicant will control.
12864 @item @code{config-file} (default: @code{#f})
12865 Optional configuration file to use.
12867 @item @code{extra-options} (default: @code{'()})
12868 List of additional command-line arguments to pass to the daemon.
12873 @defvr {Scheme Variable} iptables-service-type
12874 This is the service type to set up an iptables configuration. iptables is a
12875 packet filtering framework supported by the Linux kernel. This service
12876 supports configuring iptables for both IPv4 and IPv6. A simple example
12877 configuration rejecting all incoming connections except those to the ssh port
12881 (service iptables-service-type
12882 (iptables-configuration
12883 (ipv4-rules (plain-file "iptables.rules" "*filter
12887 -A INPUT -p tcp --dport 22 -j ACCEPT
12888 -A INPUT -j REJECT --reject-with icmp-port-unreachable
12891 (ipv6-rules (plain-file "ip6tables.rules" "*filter
12895 -A INPUT -p tcp --dport 22 -j ACCEPT
12896 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
12902 @deftp {Data Type} iptables-configuration
12903 The data type representing the configuration of iptables.
12906 @item @code{iptables} (default: @code{iptables})
12907 The iptables package that provides @code{iptables-restore} and
12908 @code{ip6tables-restore}.
12909 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
12910 The iptables rules to use. It will be passed to @code{iptables-restore}.
12911 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
12913 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
12914 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
12915 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
12920 @cindex NTP (Network Time Protocol), service
12921 @cindex real time clock
12922 @defvr {Scheme Variable} ntp-service-type
12923 This is the type of the service running the @uref{http://www.ntp.org,
12924 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
12925 system clock synchronized with that of the specified NTP servers.
12927 The value of this service is an @code{ntpd-configuration} object, as described
12931 @deftp {Data Type} ntp-configuration
12932 This is the data type for the NTP service configuration.
12935 @item @code{servers} (default: @code{%ntp-servers})
12936 This is the list of servers (host names) with which @command{ntpd} will be
12939 @item @code{allow-large-adjustment?} (default: @code{#f})
12940 This determines whether @command{ntpd} is allowed to make an initial
12941 adjustment of more than 1,000 seconds.
12943 @item @code{ntp} (default: @code{ntp})
12944 The NTP package to use.
12948 @defvr {Scheme Variable} %ntp-servers
12949 List of host names used as the default NTP servers. These are servers of the
12950 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
12954 @deffn {Scheme Procedure} openntpd-service-type
12955 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
12956 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
12957 clock synchronized with that of the given servers.
12961 openntpd-service-type
12962 (openntpd-configuration
12963 (listen-on '("127.0.0.1" "::1"))
12964 (sensor '("udcf0 correction 70000"))
12965 (constraint-from '("www.gnu.org"))
12966 (constraints-from '("https://www.google.com/"))
12967 (allow-large-adjustment? #t)))
12972 @deftp {Data Type} openntpd-configuration
12974 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
12975 The openntpd executable to use.
12976 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
12977 A list of local IP addresses or hostnames the ntpd daemon should listen on.
12978 @item @code{query-from} (default: @code{'()})
12979 A list of local IP address the ntpd daemon should use for outgoing queries.
12980 @item @code{sensor} (default: @code{'()})
12981 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
12982 will listen to each sensor that actually exists and ignore non-existent ones.
12983 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
12985 @item @code{server} (default: @var{%ntp-servers})
12986 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
12987 @item @code{servers} (default: @code{'()})
12988 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
12989 @item @code{constraint-from} (default: @code{'()})
12990 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
12991 This time information is not used for precision but acts as an authenticated
12992 constraint, thereby reducing the impact of unauthenticated NTP
12993 man-in-the-middle attacks.
12994 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
12996 @item @code{constraints-from} (default: @code{'()})
12997 As with constraint from, specify a list of URLs, IP addresses or hostnames of
12998 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
12999 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
13000 @item @code{allow-large-adjustment?} (default: @code{#f})
13001 Determines if @code{ntpd} is allowed to make an initial adjustment of more
13007 @deffn {Scheme variable} inetd-service-type
13008 This service runs the @command{inetd} (@pxref{inetd invocation,,,
13009 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
13010 connections on internet sockets, and lazily starts the specified server
13011 program when a connection is made on one of these sockets.
13013 The value of this service is an @code{inetd-configuration} object. The
13014 following example configures the @command{inetd} daemon to provide the
13015 built-in @command{echo} service, as well as an smtp service which
13016 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
13017 gateway @code{hostname}:
13022 (inetd-configuration
13026 (socket-type 'stream)
13033 (socket-type 'stream)
13037 (program (file-append openssh "/bin/ssh"))
13039 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13040 "-W" "smtp-server:25" "user@@hostname")))))
13043 See below for more details about @code{inetd-configuration}.
13046 @deftp {Data Type} inetd-configuration
13047 Data type representing the configuration of @command{inetd}.
13050 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13051 The @command{inetd} executable to use.
13053 @item @code{entries} (default: @code{'()})
13054 A list of @command{inetd} service entries. Each entry should be created
13055 by the @code{inetd-entry} constructor.
13059 @deftp {Data Type} inetd-entry
13060 Data type representing an entry in the @command{inetd} configuration.
13061 Each entry corresponds to a socket where @command{inetd} will listen for
13065 @item @code{node} (default: @code{#f})
13066 Optional string, a comma-separated list of local addresses
13067 @command{inetd} should use when listening for this service.
13068 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13069 description of all options.
13071 A string, the name must correspond to an entry in @code{/etc/services}.
13072 @item @code{socket-type}
13073 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13075 @item @code{protocol}
13076 A string, must correspond to an entry in @code{/etc/protocols}.
13077 @item @code{wait?} (default: @code{#t})
13078 Whether @command{inetd} should wait for the server to exit before
13079 listening to new service requests.
13081 A string containing the user (and, optionally, group) name of the user
13082 as whom the server should run. The group name can be specified in a
13083 suffix, separated by a colon or period, i.e.@: @code{"user"},
13084 @code{"user:group"} or @code{"user.group"}.
13085 @item @code{program} (default: @code{"internal"})
13086 The server program which will serve the requests, or @code{"internal"}
13087 if @command{inetd} should use a built-in service.
13088 @item @code{arguments} (default: @code{'()})
13089 A list strings or file-like objects, which are the server program's
13090 arguments, starting with the zeroth argument, i.e.@: the name of the
13091 program itself. For @command{inetd}'s internal services, this entry
13092 must be @code{'()} or @code{'("internal")}.
13095 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13096 detailed discussion of each configuration field.
13100 @defvr {Scheme Variable} tor-service-type
13101 This is the type for a service that runs the @uref{https://torproject.org,
13102 Tor} anonymous networking daemon. The service is configured using a
13103 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
13104 @code{tor} unprivileged user, which is a member of the @code{tor} group.
13108 @deftp {Data Type} tor-configuration
13110 @item @code{tor} (default: @code{tor})
13111 The package that provides the Tor daemon. This package is expected to provide
13112 the daemon at @file{bin/tor} relative to its output directory. The default
13113 package is the @uref{https://www.torproject.org, Tor Project's}
13116 @item @code{config-file} (default: @code{(plain-file "empty" "")})
13117 The configuration file to use. It will be appended to a default configuration
13118 file, and the final configuration file will be passed to @code{tor} via its
13119 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
13120 file-like objects}). See @code{man tor} for details on the configuration file
13123 @item @code{hidden-services} (default: @code{'()})
13124 The list of @code{<hidden-service>} records to use. For any hidden service
13125 you include in this list, appropriate configuration to enable the hidden
13126 service will be automatically added to the default configuration file. You
13127 may conveniently create @code{<hidden-service>} records using the
13128 @code{tor-hidden-service} procedure described below.
13130 @item @code{socks-socket-type} (default: @code{'tcp})
13131 The default socket type that Tor should use for its SOCKS socket. This must
13132 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
13133 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
13134 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
13135 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13138 If you want to customize the SOCKS socket in more detail, leave
13139 @code{socks-socket-type} at its default value of @code{'tcp} and use
13140 @code{config-file} to override the default by providing your own
13141 @code{SocksPort} option.
13145 @cindex hidden service
13146 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13147 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13148 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13151 '((22 "127.0.0.1:22")
13152 (80 "127.0.0.1:8080"))
13155 In this example, port 22 of the hidden service is mapped to local port 22, and
13156 port 80 is mapped to local port 8080.
13158 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13159 the @file{hostname} file contains the @code{.onion} host name for the hidden
13162 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13163 project's documentation} for more information.
13166 The @code{(gnu services rsync)} module provides the following services:
13168 You might want an rsync daemon if you have files that you want available
13169 so anyone (or just yourself) can download existing files or upload new
13172 @deffn {Scheme Variable} rsync-service-type
13173 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13174 The value for this service type is a
13175 @command{rsync-configuration} record as in this example:
13178 (service rsync-service-type)
13181 See below for details about @code{rsync-configuration}.
13184 @deftp {Data Type} rsync-configuration
13185 Data type representing the configuration for @code{rsync-service}.
13188 @item @code{package} (default: @var{rsync})
13189 @code{rsync} package to use.
13191 @item @code{port-number} (default: @code{873})
13192 TCP port on which @command{rsync} listens for incoming connections. If port
13193 is less than @code{1024} @command{rsync} needs to be started as the
13194 @code{root} user and group.
13196 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
13197 Name of the file where @command{rsync} writes its PID.
13199 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
13200 Name of the file where @command{rsync} writes its lock file.
13202 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
13203 Name of the file where @command{rsync} writes its log file.
13205 @item @code{use-chroot?} (default: @var{#t})
13206 Whether to use chroot for @command{rsync} shared directory.
13208 @item @code{share-path} (default: @file{/srv/rsync})
13209 Location of the @command{rsync} shared directory.
13211 @item @code{share-comment} (default: @code{"Rsync share"})
13212 Comment of the @command{rsync} shared directory.
13214 @item @code{read-only?} (default: @var{#f})
13215 Read-write permissions to shared directory.
13217 @item @code{timeout} (default: @code{300})
13218 I/O timeout in seconds.
13220 @item @code{user} (default: @var{"root"})
13221 Owner of the @code{rsync} process.
13223 @item @code{group} (default: @var{"root"})
13224 Group of the @code{rsync} process.
13226 @item @code{uid} (default: @var{"rsyncd"})
13227 User name or user ID that file transfers to and from that module should take
13228 place as when the daemon was run as @code{root}.
13230 @item @code{gid} (default: @var{"rsyncd"})
13231 Group name or group ID that will be used when accessing the module.
13236 Furthermore, @code{(gnu services ssh)} provides the following services.
13240 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
13241 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
13242 [#:allow-empty-passwords? #f] [#:root-login? #f] @
13243 [#:syslog-output? #t] [#:x11-forwarding? #t] @
13244 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
13245 [#:public-key-authentication? #t] [#:initialize? #t]
13246 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
13247 @var{host-key} must designate a file containing the host key, and readable
13250 When @var{daemonic?} is true, @command{lshd} will detach from the
13251 controlling terminal and log its output to syslogd, unless one sets
13252 @var{syslog-output?} to false. Obviously, it also makes lsh-service
13253 depend on existence of syslogd service. When @var{pid-file?} is true,
13254 @command{lshd} writes its PID to the file called @var{pid-file}.
13256 When @var{initialize?} is true, automatically create the seed and host key
13257 upon service activation if they do not exist yet. This may take long and
13258 require interaction.
13260 When @var{initialize?} is false, it is up to the user to initialize the
13261 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
13262 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
13263 basics,,, lsh, LSH Manual}).
13265 When @var{interfaces} is empty, lshd listens for connections on all the
13266 network interfaces; otherwise, @var{interfaces} must be a list of host names
13269 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
13270 passwords, and @var{root-login?} specifies whether to accept log-ins as
13273 The other options should be self-descriptive.
13278 @deffn {Scheme Variable} openssh-service-type
13279 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
13280 shell daemon, @command{sshd}. Its value must be an
13281 @code{openssh-configuration} record as in this example:
13284 (service openssh-service-type
13285 (openssh-configuration
13286 (x11-forwarding? #t)
13287 (permit-root-login 'without-password)
13289 `(("alice" ,(local-file "alice.pub"))
13290 ("bob" ,(local-file "bob.pub"))))))
13293 See below for details about @code{openssh-configuration}.
13295 This service can be extended with extra authorized keys, as in this
13299 (service-extension openssh-service-type
13300 (const `(("charlie"
13301 ,(local-file "charlie.pub")))))
13305 @deftp {Data Type} openssh-configuration
13306 This is the configuration record for OpenSSH's @command{sshd}.
13309 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
13310 Name of the file where @command{sshd} writes its PID.
13312 @item @code{port-number} (default: @code{22})
13313 TCP port on which @command{sshd} listens for incoming connections.
13315 @item @code{permit-root-login} (default: @code{#f})
13316 This field determines whether and when to allow logins as root. If
13317 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
13318 If it's the symbol @code{'without-password}, then root logins are
13319 permitted but not with password-based authentication.
13321 @item @code{allow-empty-passwords?} (default: @code{#f})
13322 When true, users with empty passwords may log in. When false, they may
13325 @item @code{password-authentication?} (default: @code{#t})
13326 When true, users may log in with their password. When false, they have
13327 other authentication methods.
13329 @item @code{public-key-authentication?} (default: @code{#t})
13330 When true, users may log in using public key authentication. When
13331 false, users have to use other authentication method.
13333 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
13334 This is used only by protocol version 2.
13336 @item @code{x11-forwarding?} (default: @code{#f})
13337 When true, forwarding of X11 graphical client connections is
13338 enabled---in other words, @command{ssh} options @option{-X} and
13339 @option{-Y} will work.
13341 @item @code{allow-agent-forwarding?} (default: @code{#t})
13342 Whether to allow agent forwarding.
13344 @item @code{allow-tcp-forwarding?} (default: @code{#t})
13345 Whether to allow TCP forwarding.
13347 @item @code{gateway-ports?} (default: @code{#f})
13348 Whether to allow gateway ports.
13350 @item @code{challenge-response-authentication?} (default: @code{#f})
13351 Specifies whether challenge response authentication is allowed (e.g.@: via
13354 @item @code{use-pam?} (default: @code{#t})
13355 Enables the Pluggable Authentication Module interface. If set to
13356 @code{#t}, this will enable PAM authentication using
13357 @code{challenge-response-authentication?} and
13358 @code{password-authentication?}, in addition to PAM account and session
13359 module processing for all authentication types.
13361 Because PAM challenge response authentication usually serves an
13362 equivalent role to password authentication, you should disable either
13363 @code{challenge-response-authentication?} or
13364 @code{password-authentication?}.
13366 @item @code{print-last-log?} (default: @code{#t})
13367 Specifies whether @command{sshd} should print the date and time of the
13368 last user login when a user logs in interactively.
13370 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
13371 Configures external subsystems (e.g.@: file transfer daemon).
13373 This is a list of two-element lists, each of which containing the
13374 subsystem name and a command (with optional arguments) to execute upon
13377 The command @command{internal-sftp} implements an in-process SFTP
13378 server. Alternately, one can specify the @command{sftp-server} command:
13380 (service openssh-service-type
13381 (openssh-configuration
13383 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
13386 @item @code{accepted-environment} (default: @code{'()})
13387 List of strings describing which environment variables may be exported.
13389 Each string gets on its own line. See the @code{AcceptEnv} option in
13390 @code{man sshd_config}.
13392 This example allows ssh-clients to export the @code{COLORTERM} variable.
13393 It is set by terminal emulators, which support colors. You can use it in
13394 your shell's ressource file to enable colors for the prompt and commands
13395 if this variable is set.
13398 (service openssh-service-type
13399 (openssh-configuration
13400 (accepted-environment '("COLORTERM"))))
13403 @item @code{authorized-keys} (default: @code{'()})
13404 @cindex authorized keys, SSH
13405 @cindex SSH authorized keys
13406 This is the list of authorized keys. Each element of the list is a user
13407 name followed by one or more file-like objects that represent SSH public
13411 (openssh-configuration
13413 `(("rekado" ,(local-file "rekado.pub"))
13414 ("chris" ,(local-file "chris.pub"))
13415 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
13419 registers the specified public keys for user accounts @code{rekado},
13420 @code{chris}, and @code{root}.
13422 Additional authorized keys can be specified @i{via}
13423 @code{service-extension}.
13425 Note that this does @emph{not} interfere with the use of
13426 @file{~/.ssh/authorized_keys}.
13428 @item @code{log-level} (default: @code{'info})
13429 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
13430 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
13431 page for @file{sshd_config} for the full list of level names.
13433 @item @code{extra-content} (default: @code{""})
13434 This field can be used to append arbitrary text to the configuration file. It
13435 is especially useful for elaborate configurations that cannot be expressed
13436 otherwise. This configuration, for example, would generally disable root
13437 logins, but permit them from one specific IP address:
13440 (openssh-configuration
13442 Match Address 192.168.0.1
13443 PermitRootLogin yes"))
13449 @deffn {Scheme Procedure} dropbear-service [@var{config}]
13450 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
13451 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
13454 For example, to specify a Dropbear service listening on port 1234, add
13455 this call to the operating system's @code{services} field:
13458 (dropbear-service (dropbear-configuration
13459 (port-number 1234)))
13463 @deftp {Data Type} dropbear-configuration
13464 This data type represents the configuration of a Dropbear SSH daemon.
13467 @item @code{dropbear} (default: @var{dropbear})
13468 The Dropbear package to use.
13470 @item @code{port-number} (default: 22)
13471 The TCP port where the daemon waits for incoming connections.
13473 @item @code{syslog-output?} (default: @code{#t})
13474 Whether to enable syslog output.
13476 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
13477 File name of the daemon's PID file.
13479 @item @code{root-login?} (default: @code{#f})
13480 Whether to allow @code{root} logins.
13482 @item @code{allow-empty-passwords?} (default: @code{#f})
13483 Whether to allow empty passwords.
13485 @item @code{password-authentication?} (default: @code{#t})
13486 Whether to enable password-based authentication.
13490 @defvr {Scheme Variable} %facebook-host-aliases
13491 This variable contains a string for use in @file{/etc/hosts}
13492 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
13493 line contains a entry that maps a known server name of the Facebook
13494 on-line service---e.g., @code{www.facebook.com}---to the local
13495 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
13497 This variable is typically used in the @code{hosts-file} field of an
13498 @code{operating-system} declaration (@pxref{operating-system Reference,
13499 @file{/etc/hosts}}):
13502 (use-modules (gnu) (guix))
13505 (host-name "mymachine")
13508 ;; Create a /etc/hosts file with aliases for "localhost"
13509 ;; and "mymachine", as well as for Facebook servers.
13510 (plain-file "hosts"
13511 (string-append (local-host-aliases host-name)
13512 %facebook-host-aliases))))
13515 This mechanism can prevent programs running locally, such as Web
13516 browsers, from accessing Facebook.
13519 The @code{(gnu services avahi)} provides the following definition.
13521 @defvr {Scheme Variable} avahi-service-type
13522 This is the service that runs @command{avahi-daemon}, a system-wide
13523 mDNS/DNS-SD responder that allows for service discovery and
13524 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
13525 Its value must be a @code{zero-configuration} record---see below.
13527 This service extends the name service cache daemon (nscd) so that it can
13528 resolve @code{.local} host names using
13529 @uref{http://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
13530 Service Switch}, for information on host name resolution.
13532 Additionally, add the @var{avahi} package to the system profile so that
13533 commands such as @command{avahi-browse} are directly usable.
13536 @deftp {Data Type} avahi-configuration
13537 Data type representation the configuration for Avahi.
13541 @item @code{host-name} (default: @code{#f})
13542 If different from @code{#f}, use that as the host name to
13543 publish for this machine; otherwise, use the machine's actual host name.
13545 @item @code{publish?} (default: @code{#t})
13546 When true, allow host names and services to be published (broadcast) over the
13549 @item @code{publish-workstation?} (default: @code{#t})
13550 When true, @command{avahi-daemon} publishes the machine's host name and IP
13551 address via mDNS on the local network. To view the host names published on
13552 your local network, you can run:
13555 avahi-browse _workstation._tcp
13558 @item @code{wide-area?} (default: @code{#f})
13559 When true, DNS-SD over unicast DNS is enabled.
13561 @item @code{ipv4?} (default: @code{#t})
13562 @itemx @code{ipv6?} (default: @code{#t})
13563 These fields determine whether to use IPv4/IPv6 sockets.
13565 @item @code{domains-to-browse} (default: @code{'()})
13566 This is a list of domains to browse.
13570 @deffn {Scheme Variable} openvswitch-service-type
13571 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
13572 service, whose value should be an @code{openvswitch-configuration}
13576 @deftp {Data Type} openvswitch-configuration
13577 Data type representing the configuration of Open vSwitch, a multilayer
13578 virtual switch which is designed to enable massive network automation
13579 through programmatic extension.
13582 @item @code{package} (default: @var{openvswitch})
13583 Package object of the Open vSwitch.
13589 @subsection X Window
13592 @cindex X Window System
13593 @cindex login manager
13594 Support for the X Window graphical display system---specifically
13595 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
13596 there is no @code{xorg-service} procedure. Instead, the X server is
13597 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
13600 @cindex GNOME, login manager
13601 GDM of course allows users to log in into window managers and desktop
13602 environments other than GNOME; for those using GNOME, GDM is required for
13603 features such as automatic screen locking.
13605 @cindex window manager
13606 To use X11, you must install at least one @dfn{window manager}---for
13607 example the @code{windowmaker} or @code{openbox} packages---preferably
13608 by adding it to the @code{packages} field of your operating system
13609 definition (@pxref{operating-system Reference, system-wide packages}).
13611 @defvr {Scheme Variable} gdm-service-type
13612 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
13613 Desktop Manager} (GDM), a program that manages graphical display servers and
13614 handles graphical user logins. Its value must be a @code{gdm-configuration}
13617 @cindex session types (X11)
13618 @cindex X11 session types
13619 GDM looks for @dfn{session types} described by the @file{.desktop} files in
13620 @file{/run/current-system/profile/share/xsessions} and allows users to choose
13621 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
13622 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
13623 set of packages automatically makes them available at the log-in screen.
13625 In addition, @file{~/.xsession} files are honored. When available,
13626 @file{~/.xsession} must be an executable that starts a window manager
13627 and/or other X clients.
13630 @deftp {Data Type} gdm-configuration
13632 @item @code{auto-login?} (default: @code{#f})
13633 @itemx @code{default-user} (default: @code{#f})
13634 When @code{auto-login?} is false, GDM presents a log-in screen.
13636 When @code{auto-login?} is true, GDM logs in directly as
13637 @code{default-user}.
13639 @item @code{gnome-shell-assets} (default: ...)
13640 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
13642 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
13643 Configuration of the Xorg graphical server.
13645 @item @code{xsession} (default: @code{(xinitrc)})
13646 Script to run before starting a X session.
13648 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
13649 File name of the @code{dbus-daemon} executable.
13651 @item @code{gdm} (default: @code{gdm})
13652 The GDM package to use.
13656 @defvr {Scheme Variable} slim-service-type
13657 This is the type for the SLiM graphical login manager for X11.
13659 Like GDM, SLiM looks for session types described by @file{.desktop} files and
13660 allows users to choose a session from the log-in screen using @kbd{F1}. It
13661 also honors @file{~/.xsession} files.
13663 Unlike GDM, SLiM does not spawn the user session on a different VT after
13664 logging in, which means that you can only start one graphical session. If you
13665 want to be able to run multiple graphical sessions at the same time you have
13666 to add multiple SLiM services to your system services. The following example
13667 shows how to replace the default GDM service with two SLiM services on tty7
13671 (use-modules (gnu services)
13672 (gnu services desktop)
13673 (gnu services xorg)
13674 (srfi srfi-1)) ;for 'remove'
13678 (services (cons* (service slim-service-type (slim-configuration
13681 (service slim-service-type (slim-configuration
13684 (remove (lambda (service)
13685 (eq? (service-kind service) gdm-service-type))
13686 %desktop-services))))
13691 @deftp {Data Type} slim-configuration
13692 Data type representing the configuration of @code{slim-service-type}.
13695 @item @code{allow-empty-passwords?} (default: @code{#t})
13696 Whether to allow logins with empty passwords.
13698 @item @code{auto-login?} (default: @code{#f})
13699 @itemx @code{default-user} (default: @code{""})
13700 When @code{auto-login?} is false, SLiM presents a log-in screen.
13702 When @code{auto-login?} is true, SLiM logs in directly as
13703 @code{default-user}.
13705 @item @code{theme} (default: @code{%default-slim-theme})
13706 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
13707 The graphical theme to use and its name.
13709 @item @code{auto-login-session} (default: @code{#f})
13710 If true, this must be the name of the executable to start as the default
13711 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
13713 If false, a session described by one of the available @file{.desktop}
13714 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
13718 You must install at least one window manager in the system profile or in
13719 your user profile. Failing to do that, if @code{auto-login-session} is
13720 false, you will be unable to log in.
13723 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13724 Configuration of the Xorg graphical server.
13726 @item @code{display} (default @code{":0"})
13727 The display on which to start the Xorg graphical server.
13729 @item @code{vt} (default @code{"vt7"})
13730 The VT on which to start the Xorg graphical server.
13732 @item @code{xauth} (default: @code{xauth})
13733 The XAuth package to use.
13735 @item @code{shepherd} (default: @code{shepherd})
13736 The Shepherd package used when invoking @command{halt} and
13739 @item @code{sessreg} (default: @code{sessreg})
13740 The sessreg package used in order to register the session.
13742 @item @code{slim} (default: @code{slim})
13743 The SLiM package to use.
13747 @defvr {Scheme Variable} %default-theme
13748 @defvrx {Scheme Variable} %default-theme-name
13749 The default SLiM theme and its name.
13753 @deftp {Data Type} sddm-configuration
13754 This is the data type representing the sddm service configuration.
13757 @item @code{display-server} (default: "x11")
13758 Select display server to use for the greeter. Valid values are "x11"
13761 @item @code{numlock} (default: "on")
13762 Valid values are "on", "off" or "none".
13764 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
13765 Command to run when halting.
13767 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
13768 Command to run when rebooting.
13770 @item @code{theme} (default "maldives")
13771 Theme to use. Default themes provided by SDDM are "elarun" or "maldives".
13773 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
13774 Directory to look for themes.
13776 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
13777 Directory to look for faces.
13779 @item @code{default-path} (default "/run/current-system/profile/bin")
13780 Default PATH to use.
13782 @item @code{minimum-uid} (default: 1000)
13783 Minimum UID displayed in SDDM and allowed for log-in.
13785 @item @code{maximum-uid} (default: 2000)
13786 Maximum UID to display in SDDM.
13788 @item @code{remember-last-user?} (default #t)
13789 Remember last user.
13791 @item @code{remember-last-session?} (default #t)
13792 Remember last session.
13794 @item @code{hide-users} (default "")
13795 Usernames to hide from SDDM greeter.
13797 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
13798 Users with shells listed will be hidden from the SDDM greeter.
13800 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
13801 Script to run before starting a wayland session.
13803 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
13804 Directory to look for desktop files starting wayland sessions.
13806 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13807 Configuration of the Xorg graphical server.
13809 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
13812 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
13815 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
13816 Script to run after starting xorg-server.
13818 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
13819 Script to run before stopping xorg-server.
13821 @item @code{xsession-command} (default: @code{xinitrc})
13822 Script to run before starting a X session.
13824 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
13825 Directory to look for desktop files starting X sessions.
13827 @item @code{minimum-vt} (default: 7)
13830 @item @code{auto-login-user} (default "")
13831 User to use for auto-login.
13833 @item @code{auto-login-session} (default "")
13834 Desktop file to use for auto-login.
13836 @item @code{relogin?} (default #f)
13837 Relogin after logout.
13842 @cindex login manager
13844 @deffn {Scheme Procedure} sddm-service config
13845 Return a service that spawns the SDDM graphical login manager for config of
13846 type @code{<sddm-configuration>}.
13849 (sddm-service (sddm-configuration
13850 (auto-login-user "Alice")
13851 (auto-login-session "xfce.desktop")))
13855 @cindex Xorg, configuration
13856 @deftp {Data Type} xorg-configuration
13857 This data type represents the configuration of the Xorg graphical display
13858 server. Note that there is not Xorg service; instead, the X server is started
13859 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
13860 of these display managers aggregates an @code{xorg-configuration} record.
13863 @item @code{modules} (default: @code{%default-xorg-modules})
13864 This is a list of @dfn{module packages} loaded by the Xorg
13865 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
13867 @item @code{fonts} (default: @code{%default-xorg-fonts})
13868 This is a list of font directories to add to the server's @dfn{font path}.
13870 @item @code{drivers} (default: @code{'()})
13871 This must be either the empty list, in which case Xorg chooses a graphics
13872 driver automatically, or a list of driver names that will be tried in this
13873 order---e.g., @code{("modesetting" "vesa")}.
13875 @item @code{resolutions} (default: @code{'()})
13876 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
13877 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
13880 @cindex keyboard layout, for Xorg
13881 @cindex keymap, for Xorg
13882 @item @code{keyboard-layout} (default: @code{#f})
13883 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
13884 English (``qwerty'') for a 105-key PC keyboard.
13886 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
13887 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
13888 information on how to specify the keyboard layout.
13890 @item @code{extra-config} (default: @code{'()})
13891 This is a list of strings or objects appended to the configuration file. It
13892 is used to pass extra text to be added verbatim to the configuration file.
13894 @item @code{server} (default: @code{xorg-server})
13895 This is the package providing the Xorg server.
13897 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
13898 This is the list of command-line arguments to pass to the X server. The
13899 default is @code{-nolisten tcp}.
13903 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
13904 [@var{login-manager-service-type}]
13905 Tell the log-in manager (of type @var{login-manager-service-type}) to use
13906 @var{config}, an @code{<xorg-configuration>} record.
13908 Since the Xorg configuration is embedded in the log-in manager's
13909 configuration---e.g., @code{gdm-configuration}---this procedure provides a
13910 shorthand to set the Xorg configuration.
13913 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
13914 Return a @code{startx} script in which the modules, fonts, etc. specified
13915 in @var{config}, are available. The result should be used in place of
13918 Usually the X server is started by a login manager.
13922 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
13923 Add @var{package}, a package for a screen locker or screen saver whose
13924 command is @var{program}, to the set of setuid programs and add a PAM entry
13925 for it. For example:
13928 (screen-locker-service xlockmore "xlock")
13931 makes the good ol' XlockMore usable.
13935 @node Printing Services
13936 @subsection Printing Services
13938 @cindex printer support with CUPS
13939 The @code{(gnu services cups)} module provides a Guix service definition
13940 for the CUPS printing service. To add printer support to a Guix
13941 system, add a @code{cups-service} to the operating system definition:
13943 @deffn {Scheme Variable} cups-service-type
13944 The service type for the CUPS print server. Its value should be a valid
13945 CUPS configuration (see below). To use the default settings, simply
13948 (service cups-service-type)
13952 The CUPS configuration controls the basic things about your CUPS
13953 installation: what interfaces it listens on, what to do if a print job
13954 fails, how much logging to do, and so on. To actually add a printer,
13955 you have to visit the @url{http://localhost:631} URL, or use a tool such
13956 as GNOME's printer configuration services. By default, configuring a
13957 CUPS service will generate a self-signed certificate if needed, for
13958 secure connections to the print server.
13960 Suppose you want to enable the Web interface of CUPS and also add
13961 support for Epson printers @i{via} the @code{escpr} package and for HP
13962 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
13963 like this (you need to use the @code{(gnu packages cups)} module):
13966 (service cups-service-type
13967 (cups-configuration
13968 (web-interface? #t)
13970 (list cups-filters escpr hplip-minimal))))
13973 Note: If you wish to use the Qt5 based GUI which comes with the hplip
13974 package then it is suggested that you install the @code{hplip} package,
13975 either in your OS configuration file or as your user.
13977 The available configuration parameters follow. Each parameter
13978 definition is preceded by its type; for example, @samp{string-list foo}
13979 indicates that the @code{foo} parameter should be specified as a list of
13980 strings. There is also a way to specify the configuration as a string,
13981 if you have an old @code{cupsd.conf} file that you want to port over
13982 from some other system; see the end for more details.
13984 @c The following documentation was initially generated by
13985 @c (generate-documentation) in (gnu services cups). Manually maintained
13986 @c documentation is better, so we shouldn't hesitate to edit below as
13987 @c needed. However if the change you want to make to this documentation
13988 @c can be done in an automated way, it's probably easier to change
13989 @c (generate-documentation) than to make it below and have to deal with
13990 @c the churn as CUPS updates.
13993 Available @code{cups-configuration} fields are:
13995 @deftypevr {@code{cups-configuration} parameter} package cups
13999 @deftypevr {@code{cups-configuration} parameter} package-list extensions
14000 Drivers and other extensions to the CUPS package.
14003 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
14004 Configuration of where to write logs, what directories to use for print
14005 spools, and related privileged configuration parameters.
14007 Available @code{files-configuration} fields are:
14009 @deftypevr {@code{files-configuration} parameter} log-location access-log
14010 Defines the access log filename. Specifying a blank filename disables
14011 access log generation. The value @code{stderr} causes log entries to be
14012 sent to the standard error file when the scheduler is running in the
14013 foreground, or to the system log daemon when run in the background. The
14014 value @code{syslog} causes log entries to be sent to the system log
14015 daemon. The server name may be included in filenames using the string
14016 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
14018 Defaults to @samp{"/var/log/cups/access_log"}.
14021 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
14022 Where CUPS should cache data.
14024 Defaults to @samp{"/var/cache/cups"}.
14027 @deftypevr {@code{files-configuration} parameter} string config-file-perm
14028 Specifies the permissions for all configuration files that the scheduler
14031 Note that the permissions for the printers.conf file are currently
14032 masked to only allow access from the scheduler user (typically root).
14033 This is done because printer device URIs sometimes contain sensitive
14034 authentication information that should not be generally known on the
14035 system. There is no way to disable this security feature.
14037 Defaults to @samp{"0640"}.
14040 @deftypevr {@code{files-configuration} parameter} log-location error-log
14041 Defines the error log filename. Specifying a blank filename disables
14042 error log generation. The value @code{stderr} causes log entries to be
14043 sent to the standard error file when the scheduler is running in the
14044 foreground, or to the system log daemon when run in the background. The
14045 value @code{syslog} causes log entries to be sent to the system log
14046 daemon. The server name may be included in filenames using the string
14047 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
14049 Defaults to @samp{"/var/log/cups/error_log"}.
14052 @deftypevr {@code{files-configuration} parameter} string fatal-errors
14053 Specifies which errors are fatal, causing the scheduler to exit. The
14058 No errors are fatal.
14061 All of the errors below are fatal.
14064 Browsing initialization errors are fatal, for example failed connections
14065 to the DNS-SD daemon.
14068 Configuration file syntax errors are fatal.
14071 Listen or Port errors are fatal, except for IPv6 failures on the
14072 loopback or @code{any} addresses.
14075 Log file creation or write errors are fatal.
14078 Bad startup file permissions are fatal, for example shared TLS
14079 certificate and key files with world-read permissions.
14082 Defaults to @samp{"all -browse"}.
14085 @deftypevr {@code{files-configuration} parameter} boolean file-device?
14086 Specifies whether the file pseudo-device can be used for new printer
14087 queues. The URI @uref{file:///dev/null} is always allowed.
14089 Defaults to @samp{#f}.
14092 @deftypevr {@code{files-configuration} parameter} string group
14093 Specifies the group name or ID that will be used when executing external
14096 Defaults to @samp{"lp"}.
14099 @deftypevr {@code{files-configuration} parameter} string log-file-perm
14100 Specifies the permissions for all log files that the scheduler writes.
14102 Defaults to @samp{"0644"}.
14105 @deftypevr {@code{files-configuration} parameter} log-location page-log
14106 Defines the page log filename. Specifying a blank filename disables
14107 page log generation. The value @code{stderr} causes log entries to be
14108 sent to the standard error file when the scheduler is running in the
14109 foreground, or to the system log daemon when run in the background. The
14110 value @code{syslog} causes log entries to be sent to the system log
14111 daemon. The server name may be included in filenames using the string
14112 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
14114 Defaults to @samp{"/var/log/cups/page_log"}.
14117 @deftypevr {@code{files-configuration} parameter} string remote-root
14118 Specifies the username that is associated with unauthenticated accesses
14119 by clients claiming to be the root user. The default is @code{remroot}.
14121 Defaults to @samp{"remroot"}.
14124 @deftypevr {@code{files-configuration} parameter} file-name request-root
14125 Specifies the directory that contains print jobs and other HTTP request
14128 Defaults to @samp{"/var/spool/cups"}.
14131 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
14132 Specifies the level of security sandboxing that is applied to print
14133 filters, backends, and other child processes of the scheduler; either
14134 @code{relaxed} or @code{strict}. This directive is currently only
14135 used/supported on macOS.
14137 Defaults to @samp{strict}.
14140 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
14141 Specifies the location of TLS certificates and private keys. CUPS will
14142 look for public and private keys in this directory: a @code{.crt} files
14143 for PEM-encoded certificates and corresponding @code{.key} files for
14144 PEM-encoded private keys.
14146 Defaults to @samp{"/etc/cups/ssl"}.
14149 @deftypevr {@code{files-configuration} parameter} file-name server-root
14150 Specifies the directory containing the server configuration files.
14152 Defaults to @samp{"/etc/cups"}.
14155 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
14156 Specifies whether the scheduler calls fsync(2) after writing
14157 configuration or state files.
14159 Defaults to @samp{#f}.
14162 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
14163 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
14166 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
14167 Specifies the directory where temporary files are stored.
14169 Defaults to @samp{"/var/spool/cups/tmp"}.
14172 @deftypevr {@code{files-configuration} parameter} string user
14173 Specifies the user name or ID that is used when running external
14176 Defaults to @samp{"lp"}.
14180 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
14181 Specifies the logging level for the AccessLog file. The @code{config}
14182 level logs when printers and classes are added, deleted, or modified and
14183 when configuration files are accessed or updated. The @code{actions}
14184 level logs when print jobs are submitted, held, released, modified, or
14185 canceled, and any of the conditions for @code{config}. The @code{all}
14186 level logs all requests.
14188 Defaults to @samp{actions}.
14191 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
14192 Specifies whether to purge job history data automatically when it is no
14193 longer required for quotas.
14195 Defaults to @samp{#f}.
14198 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
14199 Specifies which protocols to use for local printer sharing.
14201 Defaults to @samp{dnssd}.
14204 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
14205 Specifies whether the CUPS web interface is advertised.
14207 Defaults to @samp{#f}.
14210 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
14211 Specifies whether shared printers are advertised.
14213 Defaults to @samp{#f}.
14216 @deftypevr {@code{cups-configuration} parameter} string classification
14217 Specifies the security classification of the server. Any valid banner
14218 name can be used, including "classified", "confidential", "secret",
14219 "topsecret", and "unclassified", or the banner can be omitted to disable
14220 secure printing functions.
14222 Defaults to @samp{""}.
14225 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
14226 Specifies whether users may override the classification (cover page) of
14227 individual print jobs using the @code{job-sheets} option.
14229 Defaults to @samp{#f}.
14232 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
14233 Specifies the default type of authentication to use.
14235 Defaults to @samp{Basic}.
14238 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
14239 Specifies whether encryption will be used for authenticated requests.
14241 Defaults to @samp{Required}.
14244 @deftypevr {@code{cups-configuration} parameter} string default-language
14245 Specifies the default language to use for text and web content.
14247 Defaults to @samp{"en"}.
14250 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
14251 Specifies the default paper size for new print queues. @samp{"Auto"}
14252 uses a locale-specific default, while @samp{"None"} specifies there is
14253 no default paper size. Specific size names are typically
14254 @samp{"Letter"} or @samp{"A4"}.
14256 Defaults to @samp{"Auto"}.
14259 @deftypevr {@code{cups-configuration} parameter} string default-policy
14260 Specifies the default access policy to use.
14262 Defaults to @samp{"default"}.
14265 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
14266 Specifies whether local printers are shared by default.
14268 Defaults to @samp{#t}.
14271 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
14272 Specifies the delay for updating of configuration and state files, in
14273 seconds. A value of 0 causes the update to happen as soon as possible,
14274 typically within a few milliseconds.
14276 Defaults to @samp{30}.
14279 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
14280 Specifies what to do when an error occurs. Possible values are
14281 @code{abort-job}, which will discard the failed print job;
14282 @code{retry-job}, which will retry the job at a later time;
14283 @code{retry-this-job}, which retries the failed job immediately; and
14284 @code{stop-printer}, which stops the printer.
14286 Defaults to @samp{stop-printer}.
14289 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
14290 Specifies the maximum cost of filters that are run concurrently, which
14291 can be used to minimize disk, memory, and CPU resource problems. A
14292 limit of 0 disables filter limiting. An average print to a
14293 non-PostScript printer needs a filter limit of about 200. A PostScript
14294 printer needs about half that (100). Setting the limit below these
14295 thresholds will effectively limit the scheduler to printing a single job
14298 Defaults to @samp{0}.
14301 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
14302 Specifies the scheduling priority of filters that are run to print a
14303 job. The nice value ranges from 0, the highest priority, to 19, the
14306 Defaults to @samp{0}.
14309 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
14310 Specifies whether to do reverse lookups on connecting clients. The
14311 @code{double} setting causes @code{cupsd} to verify that the hostname
14312 resolved from the address matches one of the addresses returned for that
14313 hostname. Double lookups also prevent clients with unregistered
14314 addresses from connecting to your server. Only set this option to
14315 @code{#t} or @code{double} if absolutely required.
14317 Defaults to @samp{#f}.
14320 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
14321 Specifies the number of seconds to wait before killing the filters and
14322 backend associated with a canceled or held job.
14324 Defaults to @samp{30}.
14327 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
14328 Specifies the interval between retries of jobs in seconds. This is
14329 typically used for fax queues but can also be used with normal print
14330 queues whose error policy is @code{retry-job} or
14331 @code{retry-current-job}.
14333 Defaults to @samp{30}.
14336 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
14337 Specifies the number of retries that are done for jobs. This is
14338 typically used for fax queues but can also be used with normal print
14339 queues whose error policy is @code{retry-job} or
14340 @code{retry-current-job}.
14342 Defaults to @samp{5}.
14345 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
14346 Specifies whether to support HTTP keep-alive connections.
14348 Defaults to @samp{#t}.
14351 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
14352 Specifies how long an idle client connection remains open, in seconds.
14354 Defaults to @samp{30}.
14357 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
14358 Specifies the maximum size of print files, IPP requests, and HTML form
14359 data. A limit of 0 disables the limit check.
14361 Defaults to @samp{0}.
14364 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
14365 Listens on the specified interfaces for connections. Valid values are
14366 of the form @var{address}:@var{port}, where @var{address} is either an
14367 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
14368 indicate all addresses. Values can also be file names of local UNIX
14369 domain sockets. The Listen directive is similar to the Port directive
14370 but allows you to restrict access to specific interfaces or networks.
14373 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
14374 Specifies the number of pending connections that will be allowed. This
14375 normally only affects very busy servers that have reached the MaxClients
14376 limit, but can also be triggered by large numbers of simultaneous
14377 connections. When the limit is reached, the operating system will
14378 refuse additional connections until the scheduler can accept the pending
14381 Defaults to @samp{128}.
14384 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
14385 Specifies a set of additional access controls.
14387 Available @code{location-access-controls} fields are:
14389 @deftypevr {@code{location-access-controls} parameter} file-name path
14390 Specifies the URI path to which the access control applies.
14393 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
14394 Access controls for all access to this path, in the same format as the
14395 @code{access-controls} of @code{operation-access-control}.
14397 Defaults to @samp{()}.
14400 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
14401 Access controls for method-specific access to this path.
14403 Defaults to @samp{()}.
14405 Available @code{method-access-controls} fields are:
14407 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
14408 If @code{#t}, apply access controls to all methods except the listed
14409 methods. Otherwise apply to only the listed methods.
14411 Defaults to @samp{#f}.
14414 @deftypevr {@code{method-access-controls} parameter} method-list methods
14415 Methods to which this access control applies.
14417 Defaults to @samp{()}.
14420 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
14421 Access control directives, as a list of strings. Each string should be
14422 one directive, such as "Order allow,deny".
14424 Defaults to @samp{()}.
14429 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
14430 Specifies the number of debugging messages that are retained for logging
14431 if an error occurs in a print job. Debug messages are logged regardless
14432 of the LogLevel setting.
14434 Defaults to @samp{100}.
14437 @deftypevr {@code{cups-configuration} parameter} log-level log-level
14438 Specifies the level of logging for the ErrorLog file. The value
14439 @code{none} stops all logging while @code{debug2} logs everything.
14441 Defaults to @samp{info}.
14444 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
14445 Specifies the format of the date and time in the log files. The value
14446 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
14448 Defaults to @samp{standard}.
14451 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
14452 Specifies the maximum number of simultaneous clients that are allowed by
14455 Defaults to @samp{100}.
14458 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
14459 Specifies the maximum number of simultaneous clients that are allowed
14460 from a single address.
14462 Defaults to @samp{100}.
14465 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
14466 Specifies the maximum number of copies that a user can print of each
14469 Defaults to @samp{9999}.
14472 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
14473 Specifies the maximum time a job may remain in the @code{indefinite}
14474 hold state before it is canceled. A value of 0 disables cancellation of
14477 Defaults to @samp{0}.
14480 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
14481 Specifies the maximum number of simultaneous jobs that are allowed. Set
14482 to 0 to allow an unlimited number of jobs.
14484 Defaults to @samp{500}.
14487 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
14488 Specifies the maximum number of simultaneous jobs that are allowed per
14489 printer. A value of 0 allows up to MaxJobs jobs per printer.
14491 Defaults to @samp{0}.
14494 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
14495 Specifies the maximum number of simultaneous jobs that are allowed per
14496 user. A value of 0 allows up to MaxJobs jobs per user.
14498 Defaults to @samp{0}.
14501 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
14502 Specifies the maximum time a job may take to print before it is
14503 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
14505 Defaults to @samp{10800}.
14508 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
14509 Specifies the maximum size of the log files before they are rotated, in
14510 bytes. The value 0 disables log rotation.
14512 Defaults to @samp{1048576}.
14515 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
14516 Specifies the maximum amount of time to allow between files in a
14517 multiple file print job, in seconds.
14519 Defaults to @samp{300}.
14522 @deftypevr {@code{cups-configuration} parameter} string page-log-format
14523 Specifies the format of PageLog lines. Sequences beginning with percent
14524 (@samp{%}) characters are replaced with the corresponding information,
14525 while all other characters are copied literally. The following percent
14526 sequences are recognized:
14530 insert a single percent character
14533 insert the value of the specified IPP attribute
14536 insert the number of copies for the current page
14539 insert the current page number
14542 insert the current date and time in common log format
14548 insert the printer name
14551 insert the username
14554 A value of the empty string disables page logging. The string @code{%p
14555 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
14556 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
14559 Defaults to @samp{""}.
14562 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
14563 Passes the specified environment variable(s) to child processes; a list
14566 Defaults to @samp{()}.
14569 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
14570 Specifies named access control policies.
14572 Available @code{policy-configuration} fields are:
14574 @deftypevr {@code{policy-configuration} parameter} string name
14575 Name of the policy.
14578 @deftypevr {@code{policy-configuration} parameter} string job-private-access
14579 Specifies an access list for a job's private values. @code{@@ACL} maps
14580 to the printer's requesting-user-name-allowed or
14581 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14582 owner. @code{@@SYSTEM} maps to the groups listed for the
14583 @code{system-group} field of the @code{files-config} configuration,
14584 which is reified into the @code{cups-files.conf(5)} file. Other
14585 possible elements of the access list include specific user names, and
14586 @code{@@@var{group}} to indicate members of a specific group. The
14587 access list may also be simply @code{all} or @code{default}.
14589 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14592 @deftypevr {@code{policy-configuration} parameter} string job-private-values
14593 Specifies the list of job values to make private, or @code{all},
14594 @code{default}, or @code{none}.
14596 Defaults to @samp{"job-name job-originating-host-name
14597 job-originating-user-name phone"}.
14600 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
14601 Specifies an access list for a subscription's private values.
14602 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
14603 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14604 owner. @code{@@SYSTEM} maps to the groups listed for the
14605 @code{system-group} field of the @code{files-config} configuration,
14606 which is reified into the @code{cups-files.conf(5)} file. Other
14607 possible elements of the access list include specific user names, and
14608 @code{@@@var{group}} to indicate members of a specific group. The
14609 access list may also be simply @code{all} or @code{default}.
14611 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14614 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
14615 Specifies the list of job values to make private, or @code{all},
14616 @code{default}, or @code{none}.
14618 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
14619 notify-subscriber-user-name notify-user-data"}.
14622 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
14623 Access control by IPP operation.
14625 Defaults to @samp{()}.
14629 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
14630 Specifies whether job files (documents) are preserved after a job is
14631 printed. If a numeric value is specified, job files are preserved for
14632 the indicated number of seconds after printing. Otherwise a boolean
14633 value applies indefinitely.
14635 Defaults to @samp{86400}.
14638 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
14639 Specifies whether the job history is preserved after a job is printed.
14640 If a numeric value is specified, the job history is preserved for the
14641 indicated number of seconds after printing. If @code{#t}, the job
14642 history is preserved until the MaxJobs limit is reached.
14644 Defaults to @samp{#t}.
14647 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
14648 Specifies the amount of time to wait for job completion before
14649 restarting the scheduler.
14651 Defaults to @samp{30}.
14654 @deftypevr {@code{cups-configuration} parameter} string rip-cache
14655 Specifies the maximum amount of memory to use when converting documents
14656 into bitmaps for a printer.
14658 Defaults to @samp{"128m"}.
14661 @deftypevr {@code{cups-configuration} parameter} string server-admin
14662 Specifies the email address of the server administrator.
14664 Defaults to @samp{"root@@localhost.localdomain"}.
14667 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
14668 The ServerAlias directive is used for HTTP Host header validation when
14669 clients connect to the scheduler from external interfaces. Using the
14670 special name @code{*} can expose your system to known browser-based DNS
14671 rebinding attacks, even when accessing sites through a firewall. If the
14672 auto-discovery of alternate names does not work, we recommend listing
14673 each alternate name with a ServerAlias directive instead of using
14676 Defaults to @samp{*}.
14679 @deftypevr {@code{cups-configuration} parameter} string server-name
14680 Specifies the fully-qualified host name of the server.
14682 Defaults to @samp{"localhost"}.
14685 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
14686 Specifies what information is included in the Server header of HTTP
14687 responses. @code{None} disables the Server header. @code{ProductOnly}
14688 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
14689 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
14690 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
14691 the output of the @code{uname} command. @code{Full} reports @code{CUPS
14692 2.0.0 (@var{uname}) IPP/2.0}.
14694 Defaults to @samp{Minimal}.
14697 @deftypevr {@code{cups-configuration} parameter} string set-env
14698 Set the specified environment variable to be passed to child processes.
14700 Defaults to @samp{"variable value"}.
14703 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
14704 Listens on the specified interfaces for encrypted connections. Valid
14705 values are of the form @var{address}:@var{port}, where @var{address} is
14706 either an IPv6 address enclosed in brackets, an IPv4 address, or
14707 @code{*} to indicate all addresses.
14709 Defaults to @samp{()}.
14712 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
14713 Sets encryption options. By default, CUPS only supports encryption
14714 using TLS v1.0 or higher using known secure cipher suites. The
14715 @code{AllowRC4} option enables the 128-bit RC4 cipher suites, which are
14716 required for some older clients that do not implement newer ones. The
14717 @code{AllowSSL3} option enables SSL v3.0, which is required for some
14718 older clients that do not support TLS v1.0.
14720 Defaults to @samp{()}.
14723 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
14724 Specifies whether the scheduler requires clients to strictly adhere to
14725 the IPP specifications.
14727 Defaults to @samp{#f}.
14730 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
14731 Specifies the HTTP request timeout, in seconds.
14733 Defaults to @samp{300}.
14737 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
14738 Specifies whether the web interface is enabled.
14740 Defaults to @samp{#f}.
14743 At this point you're probably thinking ``oh dear, Guix manual, I like
14744 you but you can stop already with the configuration options''. Indeed.
14745 However, one more point: it could be that you have an existing
14746 @code{cupsd.conf} that you want to use. In that case, you can pass an
14747 @code{opaque-cups-configuration} as the configuration of a
14748 @code{cups-service-type}.
14750 Available @code{opaque-cups-configuration} fields are:
14752 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
14756 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
14757 The contents of the @code{cupsd.conf}, as a string.
14760 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
14761 The contents of the @code{cups-files.conf} file, as a string.
14764 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
14765 strings of the same name, you could instantiate a CUPS service like
14769 (service cups-service-type
14770 (opaque-cups-configuration
14771 (cupsd.conf cupsd.conf)
14772 (cups-files.conf cups-files.conf)))
14776 @node Desktop Services
14777 @subsection Desktop Services
14779 The @code{(gnu services desktop)} module provides services that are
14780 usually useful in the context of a ``desktop'' setup---that is, on a
14781 machine running a graphical display server, possibly with graphical user
14782 interfaces, etc. It also defines services that provide specific desktop
14783 environments like GNOME, Xfce or MATE.
14785 To simplify things, the module defines a variable containing the set of
14786 services that users typically expect on a machine with a graphical
14787 environment and networking:
14789 @defvr {Scheme Variable} %desktop-services
14790 This is a list of services that builds upon @code{%base-services} and
14791 adds or adjusts services for a typical ``desktop'' setup.
14793 In particular, it adds a graphical login manager (@pxref{X Window,
14794 @code{gdm-service-type}}), screen lockers, a network management tool
14795 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
14796 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
14797 energy and color management services, the @code{elogind} login and seat
14798 manager, the Polkit privilege service, the GeoClue location service, the
14799 AccountsService daemon that allows authorized users change system passwords,
14800 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
14801 name service switch service configured to be able to use @code{nss-mdns}
14802 (@pxref{Name Service Switch, mDNS}).
14805 The @code{%desktop-services} variable can be used as the @code{services}
14806 field of an @code{operating-system} declaration (@pxref{operating-system
14807 Reference, @code{services}}).
14809 Additionally, the @code{gnome-desktop-service-type},
14810 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
14811 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
14812 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
14813 services like the backlight adjustment helpers and the power management
14814 utilities are added to the system, extending @code{polkit} and @code{dbus}
14815 appropriately, allowing GNOME to operate with elevated privileges on a
14816 limited number of special-purpose system interfaces. Additionally,
14817 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
14818 metapackage to the system profile. Likewise, adding the Xfce service
14819 not only adds the @code{xfce} metapackage to the system profile, but it
14820 also gives the Thunar file manager the ability to open a ``root-mode''
14821 file management window, if the user authenticates using the
14822 administrator's password via the standard polkit graphical interface.
14823 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
14824 appropriately, allowing MATE to operate with elevated privileges on a
14825 limited number of special-purpose system interfaces. Additionally,
14826 adding a service of type @code{mate-desktop-service-type} adds the MATE
14827 metapackage to the system profile. ``Adding Enlightenment'' means that
14828 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
14829 are set as setuid, allowing Enlightenment's screen locker and other
14830 functionality to work as expetected.
14832 The desktop environments in Guix use the Xorg display server by
14833 default. If you'd like to use the newer display server protocol
14834 called Wayland, you need to use the @code{sddm-service} instead of
14835 GDM as the graphical login manager. You should then
14836 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
14837 also try starting GNOME on Wayland manually from a TTY with the
14838 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
14839 gnome-session``. Currently only GNOME has support for Wayland.
14841 @defvr {Scheme Variable} gnome-desktop-service-type
14842 This is the type of the service that adds the @uref{https://www.gnome.org,
14843 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
14844 object (see below.)
14846 This service adds the @code{gnome} package to the system profile, and extends
14847 polkit with the actions from @code{gnome-settings-daemon}.
14850 @deftp {Data Type} gnome-desktop-configuration
14851 Configuration record for the GNOME desktop environment.
14854 @item @code{gnome} (default: @code{gnome})
14855 The GNOME package to use.
14859 @defvr {Scheme Variable} xfce-desktop-service-type
14860 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
14861 desktop environment. Its value is an @code{xfce-desktop-configuration} object
14864 This service adds the @code{xfce} package to the system profile, and
14865 extends polkit with the ability for @code{thunar} to manipulate the file
14866 system as root from within a user session, after the user has authenticated
14867 with the administrator's password.
14870 @deftp {Data Type} xfce-desktop-configuration
14871 Configuration record for the Xfce desktop environment.
14874 @item @code{xfce} (default: @code{xfce})
14875 The Xfce package to use.
14879 @deffn {Scheme Variable} mate-desktop-service-type
14880 This is the type of the service that runs the @uref{https://mate-desktop.org/,
14881 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
14882 object (see below.)
14884 This service adds the @code{mate} package to the system
14885 profile, and extends polkit with the actions from
14886 @code{mate-settings-daemon}.
14889 @deftp {Data Type} mate-desktop-configuration
14890 Configuration record for the MATE desktop environment.
14893 @item @code{mate} (default: @code{mate})
14894 The MATE package to use.
14898 @deffn {Scheme Variable} enlightenment-desktop-service-type
14899 Return a service that adds the @code{enlightenment} package to the system
14900 profile, and extends dbus with actions from @code{efl}.
14903 @deftp {Data Type} enlightenment-desktop-service-configuration
14905 @item @code{enlightenment} (default: @code{enlightenment})
14906 The enlightenment package to use.
14910 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
14911 the default @code{%desktop-services} variable doesn't include any of
14912 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
14913 @code{%desktop-services} in the @code{services} field of your
14914 @code{operating-system}:
14917 (use-modules (gnu))
14918 (use-service-modules desktop)
14921 ;; cons* adds items to the list given as its last argument.
14922 (services (cons* (service gnome-desktop-service-type)
14923 (service xfce-desktop-service)
14924 %desktop-services))
14928 These desktop environments will then be available as options in the
14929 graphical login window.
14931 The actual service definitions included in @code{%desktop-services} and
14932 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
14933 are described below.
14935 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
14936 Return a service that runs the ``system bus'', using @var{dbus}, with
14937 support for @var{services}.
14939 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
14940 facility. Its system bus is used to allow system services to communicate
14941 and to be notified of system-wide events.
14943 @var{services} must be a list of packages that provide an
14944 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
14945 and policy files. For example, to allow avahi-daemon to use the system bus,
14946 @var{services} must be equal to @code{(list avahi)}.
14949 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
14950 Return a service that runs the @code{elogind} login and
14951 seat management daemon. @uref{https://github.com/elogind/elogind,
14952 Elogind} exposes a D-Bus interface that can be used to know which users
14953 are logged in, know what kind of sessions they have open, suspend the
14954 system, inhibit system suspend, reboot the system, and other tasks.
14956 Elogind handles most system-level power events for a computer, for
14957 example suspending the system when a lid is closed, or shutting it down
14958 when the power button is pressed.
14960 The @var{config} keyword argument specifies the configuration for
14961 elogind, and should be the result of an @code{(elogind-configuration
14962 (@var{parameter} @var{value})...)} invocation. Available parameters and
14963 their default values are:
14966 @item kill-user-processes?
14968 @item kill-only-users
14970 @item kill-exclude-users
14972 @item inhibit-delay-max-seconds
14974 @item handle-power-key
14976 @item handle-suspend-key
14978 @item handle-hibernate-key
14980 @item handle-lid-switch
14982 @item handle-lid-switch-docked
14984 @item power-key-ignore-inhibited?
14986 @item suspend-key-ignore-inhibited?
14988 @item hibernate-key-ignore-inhibited?
14990 @item lid-switch-ignore-inhibited?
14992 @item holdoff-timeout-seconds
14996 @item idle-action-seconds
14998 @item runtime-directory-size-percent
15000 @item runtime-directory-size
15004 @item suspend-state
15005 @code{("mem" "standby" "freeze")}
15008 @item hibernate-state
15010 @item hibernate-mode
15011 @code{("platform" "shutdown")}
15012 @item hybrid-sleep-state
15014 @item hybrid-sleep-mode
15015 @code{("suspend" "platform" "shutdown")}
15019 @deffn {Scheme Procedure} accountsservice-service @
15020 [#:accountsservice @var{accountsservice}]
15021 Return a service that runs AccountsService, a system service that can
15022 list available accounts, change their passwords, and so on.
15023 AccountsService integrates with PolicyKit to enable unprivileged users
15024 to acquire the capability to modify their system configuration.
15025 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
15026 accountsservice web site} for more information.
15028 The @var{accountsservice} keyword argument is the @code{accountsservice}
15029 package to expose as a service.
15032 @deffn {Scheme Procedure} polkit-service @
15033 [#:polkit @var{polkit}]
15034 Return a service that runs the
15035 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
15036 management service}, which allows system administrators to grant access to
15037 privileged operations in a structured way. By querying the Polkit service, a
15038 privileged system component can know when it should grant additional
15039 capabilities to ordinary users. For example, an ordinary user can be granted
15040 the capability to suspend the system if the user is logged in locally.
15043 @defvr {Scheme Variable} upower-service-type
15044 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
15045 system-wide monitor for power consumption and battery levels, with the given
15046 configuration settings.
15048 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
15049 notably used by GNOME.
15052 @deftp {Data Type} upower-configuration
15053 Data type representation the configuration for UPower.
15057 @item @code{upower} (default: @var{upower})
15058 Package to use for @code{upower}.
15060 @item @code{watts-up-pro?} (default: @code{#f})
15061 Enable the Watts Up Pro device.
15063 @item @code{poll-batteries?} (default: @code{#t})
15064 Enable polling the kernel for battery level changes.
15066 @item @code{ignore-lid?} (default: @code{#f})
15067 Ignore the lid state, this can be useful if it's incorrect on a device.
15069 @item @code{use-percentage-for-policy?} (default: @code{#f})
15070 Whether battery percentage based policy should be used. The default is to use
15071 the time left, change to @code{#t} to use the percentage.
15073 @item @code{percentage-low} (default: @code{10})
15074 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15075 at which the battery is considered low.
15077 @item @code{percentage-critical} (default: @code{3})
15078 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15079 at which the battery is considered critical.
15081 @item @code{percentage-action} (default: @code{2})
15082 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15083 at which action will be taken.
15085 @item @code{time-low} (default: @code{1200})
15086 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15087 seconds at which the battery is considered low.
15089 @item @code{time-critical} (default: @code{300})
15090 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15091 seconds at which the battery is considered critical.
15093 @item @code{time-action} (default: @code{120})
15094 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15095 seconds at which action will be taken.
15097 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
15098 The action taken when @code{percentage-action} or @code{time-action} is
15099 reached (depending on the configuration of @code{use-percentage-for-policy?}).
15101 Possible values are:
15111 @code{'hybrid-sleep}.
15117 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
15118 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
15119 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
15120 notifications and ways to mount/unmount disks. Programs that talk to UDisks
15121 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
15124 @deffn {Scheme Procedure} colord-service [#:colord @var{colord}]
15125 Return a service that runs @command{colord}, a system service with a D-Bus
15126 interface to manage the color profiles of input and output devices such as
15127 screens and scanners. It is notably used by the GNOME Color Manager graphical
15128 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
15129 site} for more information.
15132 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
15133 Return a configuration allowing an application to access GeoClue
15134 location data. @var{name} is the Desktop ID of the application, without
15135 the @code{.desktop} part. If @var{allowed?} is true, the application
15136 will have access to location information by default. The boolean
15137 @var{system?} value indicates whether an application is a system component
15138 or not. Finally @var{users} is a list of UIDs of all users for which
15139 this application is allowed location info access. An empty users list
15140 means that all users are allowed.
15143 @defvr {Scheme Variable} %standard-geoclue-applications
15144 The standard list of well-known GeoClue application configurations,
15145 granting authority to the GNOME date-and-time utility to ask for the
15146 current location in order to set the time zone, and allowing the
15147 IceCat and Epiphany web browsers to request location information.
15148 IceCat and Epiphany both query the user before allowing a web page to
15149 know the user's location.
15152 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
15153 [#:whitelist '()] @
15154 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
15155 [#:submit-data? #f]
15156 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
15157 [#:submission-nick "geoclue"] @
15158 [#:applications %standard-geoclue-applications]
15159 Return a service that runs the GeoClue location service. This service
15160 provides a D-Bus interface to allow applications to request access to a
15161 user's physical location, and optionally to add information to online
15162 location databases. See
15163 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
15164 web site} for more information.
15167 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
15168 [@w{#:auto-enable? #f}]
15169 Return a service that runs the @command{bluetoothd} daemon, which
15170 manages all the Bluetooth devices and provides a number of D-Bus
15171 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
15172 powered automatically at boot, which can be useful when using a
15173 bluetooth keyboard or mouse.
15175 Users need to be in the @code{lp} group to access the D-Bus service.
15178 @node Sound Services
15179 @subsection Sound Services
15181 @cindex sound support
15183 @cindex PulseAudio, sound support
15185 The @code{(gnu services sound)} module provides a service to configure the
15186 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
15187 preferred ALSA output driver.
15189 @deffn {Scheme Variable} alsa-service-type
15190 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
15191 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
15192 configuration file. The value for this type is a @command{alsa-configuration}
15193 record as in this example:
15196 (service alsa-service-type)
15199 See below for details about @code{alsa-configuration}.
15202 @deftp {Data Type} alsa-configuration
15203 Data type representing the configuration for @code{alsa-service}.
15206 @item @code{alsa-plugins} (default: @var{alsa-plugins})
15207 @code{alsa-plugins} package to use.
15209 @item @code{pulseaudio?} (default: @var{#t})
15210 Whether ALSA applications should transparently be made to use the
15211 @uref{http://www.pulseaudio.org/, PulseAudio} sound server.
15213 Using PulseAudio allows you to run several sound-producing applications
15214 at the same time and to individual control them @i{via}
15215 @command{pavucontrol}, among other things.
15217 @item @code{extra-options} (default: @var{""})
15218 String to append to the @file{/etc/asound.conf} file.
15223 Individual users who want to override the system configuration of ALSA can do
15224 it with the @file{~/.asoundrc} file:
15227 # In guix, we have to specify the absolute path for plugins.
15229 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
15232 # Routing ALSA to jack:
15233 # <http://jackaudio.org/faq/routing_alsa.html>.
15237 0 system:playback_1
15238 1 system:playback_2
15255 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
15259 @node Database Services
15260 @subsection Database Services
15264 The @code{(gnu services databases)} module provides the following services.
15266 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
15267 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
15268 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
15269 Return a service that runs @var{postgresql}, the PostgreSQL database
15272 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
15273 creates a database cluster with @var{locale} as the default
15274 locale, stored in @var{data-directory}. It then listens on @var{port}.
15276 @cindex postgresql extension-packages
15277 Additional extensions are loaded from packages listed in
15278 @var{extension-packages}. Extensions are available at runtime. For instance,
15279 to create a geographic database using the @code{postgis} extension, a user can
15280 configure the postgresql-service as in this example:
15284 (use-package-modules databases geo)
15288 ;; postgresql is required to run `psql' but postgis is not required for
15289 ;; proper operation.
15290 (packages (cons* postgresql %base-packages))
15293 (postgresql-service #:extension-packages (list postgis))
15297 Then the extension becomes visible and you can initialise an empty geographic
15298 database in this way:
15302 > create database postgistest;
15303 > \connect postgistest;
15304 > create extension postgis;
15305 > create extension postgis_topology;
15308 There is no need to add this field for contrib extensions such as hstore or
15309 dblink as they are already loadable by postgresql. This field is only
15310 required to add extensions provided by other packages.
15313 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
15314 Return a service that runs @command{mysqld}, the MySQL or MariaDB
15317 The optional @var{config} argument specifies the configuration for
15318 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
15321 @deftp {Data Type} mysql-configuration
15322 Data type representing the configuration of @var{mysql-service}.
15325 @item @code{mysql} (default: @var{mariadb})
15326 Package object of the MySQL database server, can be either @var{mariadb}
15329 For MySQL, a temporary root password will be displayed at activation time.
15330 For MariaDB, the root password is empty.
15332 @item @code{port} (default: @code{3306})
15333 TCP port on which the database server listens for incoming connections.
15337 @defvr {Scheme Variable} memcached-service-type
15338 This is the service type for the @uref{https://memcached.org/,
15339 Memcached} service, which provides a distributed in memory cache. The
15340 value for the service type is a @code{memcached-configuration} object.
15344 (service memcached-service-type)
15347 @deftp {Data Type} memcached-configuration
15348 Data type representing the configuration of memcached.
15351 @item @code{memcached} (default: @code{memcached})
15352 The Memcached package to use.
15354 @item @code{interfaces} (default: @code{'("0.0.0.0")})
15355 Network interfaces on which to listen.
15357 @item @code{tcp-port} (default: @code{11211})
15358 Port on which to accept connections on,
15360 @item @code{udp-port} (default: @code{11211})
15361 Port on which to accept UDP connections on, a value of 0 will disable
15362 listening on a UDP socket.
15364 @item @code{additional-options} (default: @code{'()})
15365 Additional command line options to pass to @code{memcached}.
15369 @defvr {Scheme Variable} mongodb-service-type
15370 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
15371 The value for the service type is a @code{mongodb-configuration} object.
15375 (service mongodb-service-type)
15378 @deftp {Data Type} mongodb-configuration
15379 Data type representing the configuration of mongodb.
15382 @item @code{mongodb} (default: @code{mongodb})
15383 The MongoDB package to use.
15385 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
15386 The configuration file for MongoDB.
15388 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
15389 This value is used to create the directory, so that it exists and is
15390 owned by the mongodb user. It should match the data-directory which
15391 MongoDB is configured to use through the configuration file.
15395 @defvr {Scheme Variable} redis-service-type
15396 This is the service type for the @uref{https://redis.io/, Redis}
15397 key/value store, whose value is a @code{redis-configuration} object.
15400 @deftp {Data Type} redis-configuration
15401 Data type representing the configuration of redis.
15404 @item @code{redis} (default: @code{redis})
15405 The Redis package to use.
15407 @item @code{bind} (default: @code{"127.0.0.1"})
15408 Network interface on which to listen.
15410 @item @code{port} (default: @code{6379})
15411 Port on which to accept connections on, a value of 0 will disable
15412 listening on a TCP socket.
15414 @item @code{working-directory} (default: @code{"/var/lib/redis"})
15415 Directory in which to store the database and related files.
15419 @node Mail Services
15420 @subsection Mail Services
15424 The @code{(gnu services mail)} module provides Guix service definitions
15425 for email services: IMAP, POP3, and LMTP servers, as well as mail
15426 transport agents (MTAs). Lots of acronyms! These services are detailed
15427 in the subsections below.
15429 @subsubheading Dovecot Service
15431 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
15432 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
15435 By default, Dovecot does not need much configuration; the default
15436 configuration object created by @code{(dovecot-configuration)} will
15437 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
15438 certificate will be generated for TLS-protected connections, though
15439 Dovecot will also listen on cleartext ports by default. There are a
15440 number of options, though, which mail administrators might need to change,
15441 and as is the case with other services, Guix allows the system
15442 administrator to specify these parameters via a uniform Scheme interface.
15444 For example, to specify that mail is located at @code{maildir~/.mail},
15445 one would instantiate the Dovecot service like this:
15448 (dovecot-service #:config
15449 (dovecot-configuration
15450 (mail-location "maildir:~/.mail")))
15453 The available configuration parameters follow. Each parameter
15454 definition is preceded by its type; for example, @samp{string-list foo}
15455 indicates that the @code{foo} parameter should be specified as a list of
15456 strings. There is also a way to specify the configuration as a string,
15457 if you have an old @code{dovecot.conf} file that you want to port over
15458 from some other system; see the end for more details.
15460 @c The following documentation was initially generated by
15461 @c (generate-documentation) in (gnu services mail). Manually maintained
15462 @c documentation is better, so we shouldn't hesitate to edit below as
15463 @c needed. However if the change you want to make to this documentation
15464 @c can be done in an automated way, it's probably easier to change
15465 @c (generate-documentation) than to make it below and have to deal with
15466 @c the churn as dovecot updates.
15468 Available @code{dovecot-configuration} fields are:
15470 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
15471 The dovecot package.
15474 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
15475 A list of IPs or hosts where to listen for connections. @samp{*}
15476 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
15477 interfaces. If you want to specify non-default ports or anything more
15478 complex, customize the address and port fields of the
15479 @samp{inet-listener} of the specific services you are interested in.
15482 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
15483 List of protocols we want to serve. Available protocols include
15484 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
15486 Available @code{protocol-configuration} fields are:
15488 @deftypevr {@code{protocol-configuration} parameter} string name
15489 The name of the protocol.
15492 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
15493 UNIX socket path to the master authentication server to find users.
15494 This is used by imap (for shared users) and lda.
15495 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
15498 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
15499 Space separated list of plugins to load.
15502 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
15503 Maximum number of IMAP connections allowed for a user from each IP
15504 address. NOTE: The username is compared case-sensitively.
15505 Defaults to @samp{10}.
15510 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
15511 List of services to enable. Available services include @samp{imap},
15512 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
15515 Available @code{service-configuration} fields are:
15517 @deftypevr {@code{service-configuration} parameter} string kind
15518 The service kind. Valid values include @code{director},
15519 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
15520 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
15521 @code{tcpwrap}, @code{quota-warning}, or anything else.
15524 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
15525 Listeners for the service. A listener is either a
15526 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
15527 an @code{inet-listener-configuration}.
15528 Defaults to @samp{()}.
15530 Available @code{unix-listener-configuration} fields are:
15532 @deftypevr {@code{unix-listener-configuration} parameter} string path
15533 Path to the file, relative to @code{base-dir} field. This is also used as
15537 @deftypevr {@code{unix-listener-configuration} parameter} string mode
15538 The access mode for the socket.
15539 Defaults to @samp{"0600"}.
15542 @deftypevr {@code{unix-listener-configuration} parameter} string user
15543 The user to own the socket.
15544 Defaults to @samp{""}.
15547 @deftypevr {@code{unix-listener-configuration} parameter} string group
15548 The group to own the socket.
15549 Defaults to @samp{""}.
15553 Available @code{fifo-listener-configuration} fields are:
15555 @deftypevr {@code{fifo-listener-configuration} parameter} string path
15556 Path to the file, relative to @code{base-dir} field. This is also used as
15560 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
15561 The access mode for the socket.
15562 Defaults to @samp{"0600"}.
15565 @deftypevr {@code{fifo-listener-configuration} parameter} string user
15566 The user to own the socket.
15567 Defaults to @samp{""}.
15570 @deftypevr {@code{fifo-listener-configuration} parameter} string group
15571 The group to own the socket.
15572 Defaults to @samp{""}.
15576 Available @code{inet-listener-configuration} fields are:
15578 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
15579 The protocol to listen for.
15582 @deftypevr {@code{inet-listener-configuration} parameter} string address
15583 The address on which to listen, or empty for all addresses.
15584 Defaults to @samp{""}.
15587 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
15588 The port on which to listen.
15591 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
15592 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
15594 Defaults to @samp{#t}.
15599 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
15600 Maximum number of simultaneous client connections per process. Once
15601 this number of connections is received, the next incoming connection
15602 will prompt Dovecot to spawn another process. If set to 0,
15603 @code{default-client-limit} is used instead.
15605 Defaults to @samp{0}.
15609 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
15610 Number of connections to handle before starting a new process.
15611 Typically the only useful values are 0 (unlimited) or 1. 1 is more
15612 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
15613 Defaults to @samp{1}.
15617 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
15618 Maximum number of processes that can exist for this service. If set to
15619 0, @code{default-process-limit} is used instead.
15621 Defaults to @samp{0}.
15625 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
15626 Number of processes to always keep waiting for more connections.
15627 Defaults to @samp{0}.
15630 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
15631 If you set @samp{service-count 0}, you probably need to grow
15633 Defaults to @samp{256000000}.
15638 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
15639 Dict configuration, as created by the @code{dict-configuration}
15642 Available @code{dict-configuration} fields are:
15644 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
15645 A list of key-value pairs that this dict should hold.
15646 Defaults to @samp{()}.
15651 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
15652 A list of passdb configurations, each one created by the
15653 @code{passdb-configuration} constructor.
15655 Available @code{passdb-configuration} fields are:
15657 @deftypevr {@code{passdb-configuration} parameter} string driver
15658 The driver that the passdb should use. Valid values include
15659 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
15661 Defaults to @samp{"pam"}.
15664 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
15665 Space separated list of arguments to the passdb driver.
15666 Defaults to @samp{""}.
15671 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
15672 List of userdb configurations, each one created by the
15673 @code{userdb-configuration} constructor.
15675 Available @code{userdb-configuration} fields are:
15677 @deftypevr {@code{userdb-configuration} parameter} string driver
15678 The driver that the userdb should use. Valid values include
15679 @samp{passwd} and @samp{static}.
15680 Defaults to @samp{"passwd"}.
15683 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
15684 Space separated list of arguments to the userdb driver.
15685 Defaults to @samp{""}.
15688 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
15689 Override fields from passwd.
15690 Defaults to @samp{()}.
15695 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
15696 Plug-in configuration, created by the @code{plugin-configuration}
15700 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
15701 List of namespaces. Each item in the list is created by the
15702 @code{namespace-configuration} constructor.
15704 Available @code{namespace-configuration} fields are:
15706 @deftypevr {@code{namespace-configuration} parameter} string name
15707 Name for this namespace.
15710 @deftypevr {@code{namespace-configuration} parameter} string type
15711 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
15712 Defaults to @samp{"private"}.
15715 @deftypevr {@code{namespace-configuration} parameter} string separator
15716 Hierarchy separator to use. You should use the same separator for
15717 all namespaces or some clients get confused. @samp{/} is usually a good
15718 one. The default however depends on the underlying mail storage
15720 Defaults to @samp{""}.
15723 @deftypevr {@code{namespace-configuration} parameter} string prefix
15724 Prefix required to access this namespace. This needs to be
15725 different for all namespaces. For example @samp{Public/}.
15726 Defaults to @samp{""}.
15729 @deftypevr {@code{namespace-configuration} parameter} string location
15730 Physical location of the mailbox. This is in the same format as
15731 mail_location, which is also the default for it.
15732 Defaults to @samp{""}.
15735 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
15736 There can be only one INBOX, and this setting defines which
15738 Defaults to @samp{#f}.
15741 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
15742 If namespace is hidden, it's not advertised to clients via NAMESPACE
15743 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
15744 useful when converting from another server with different namespaces
15745 which you want to deprecate but still keep working. For example you can
15746 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
15748 Defaults to @samp{#f}.
15751 @deftypevr {@code{namespace-configuration} parameter} boolean list?
15752 Show the mailboxes under this namespace with the LIST command. This
15753 makes the namespace visible for clients that do not support the NAMESPACE
15754 extension. The special @code{children} value lists child mailboxes, but
15755 hides the namespace prefix.
15756 Defaults to @samp{#t}.
15759 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
15760 Namespace handles its own subscriptions. If set to @code{#f}, the
15761 parent namespace handles them. The empty prefix should always have this
15763 Defaults to @samp{#t}.
15766 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
15767 List of predefined mailboxes in this namespace.
15768 Defaults to @samp{()}.
15770 Available @code{mailbox-configuration} fields are:
15772 @deftypevr {@code{mailbox-configuration} parameter} string name
15773 Name for this mailbox.
15776 @deftypevr {@code{mailbox-configuration} parameter} string auto
15777 @samp{create} will automatically create this mailbox.
15778 @samp{subscribe} will both create and subscribe to the mailbox.
15779 Defaults to @samp{"no"}.
15782 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
15783 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
15784 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
15785 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
15786 Defaults to @samp{()}.
15793 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
15794 Base directory where to store runtime data.
15795 Defaults to @samp{"/var/run/dovecot/"}.
15798 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
15799 Greeting message for clients.
15800 Defaults to @samp{"Dovecot ready."}.
15803 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
15804 List of trusted network ranges. Connections from these IPs are
15805 allowed to override their IP addresses and ports (for logging and for
15806 authentication checks). @samp{disable-plaintext-auth} is also ignored
15807 for these networks. Typically you would specify your IMAP proxy servers
15809 Defaults to @samp{()}.
15812 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
15813 List of login access check sockets (e.g.@: tcpwrap).
15814 Defaults to @samp{()}.
15817 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
15818 Show more verbose process titles (in ps). Currently shows user name
15819 and IP address. Useful for seeing who is actually using the IMAP
15820 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
15822 Defaults to @samp{#f}.
15825 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
15826 Should all processes be killed when Dovecot master process shuts down.
15827 Setting this to @code{#f} means that Dovecot can be upgraded without
15828 forcing existing client connections to close (although that could also
15829 be a problem if the upgrade is e.g.@: due to a security fix).
15830 Defaults to @samp{#t}.
15833 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
15834 If non-zero, run mail commands via this many connections to doveadm
15835 server, instead of running them directly in the same process.
15836 Defaults to @samp{0}.
15839 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
15840 UNIX socket or host:port used for connecting to doveadm server.
15841 Defaults to @samp{"doveadm-server"}.
15844 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
15845 List of environment variables that are preserved on Dovecot startup
15846 and passed down to all of its child processes. You can also give
15847 key=value pairs to always set specific settings.
15850 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
15851 Disable LOGIN command and all other plaintext authentications unless
15852 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
15853 matches the local IP (i.e.@: you're connecting from the same computer),
15854 the connection is considered secure and plaintext authentication is
15855 allowed. See also ssl=required setting.
15856 Defaults to @samp{#t}.
15859 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
15860 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
15861 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
15862 for caching to be used.
15863 Defaults to @samp{0}.
15866 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
15867 Time to live for cached data. After TTL expires the cached record
15868 is no longer used, *except* if the main database lookup returns internal
15869 failure. We also try to handle password changes automatically: If
15870 user's previous authentication was successful, but this one wasn't, the
15871 cache isn't used. For now this works only with plaintext
15873 Defaults to @samp{"1 hour"}.
15876 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
15877 TTL for negative hits (user not found, password mismatch).
15878 0 disables caching them completely.
15879 Defaults to @samp{"1 hour"}.
15882 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
15883 List of realms for SASL authentication mechanisms that need them.
15884 You can leave it empty if you don't want to support multiple realms.
15885 Many clients simply use the first one listed here, so keep the default
15887 Defaults to @samp{()}.
15890 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
15891 Default realm/domain to use if none was specified. This is used for
15892 both SASL realms and appending @@domain to username in plaintext
15894 Defaults to @samp{""}.
15897 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
15898 List of allowed characters in username. If the user-given username
15899 contains a character not listed in here, the login automatically fails.
15900 This is just an extra check to make sure user can't exploit any
15901 potential quote escaping vulnerabilities with SQL/LDAP databases. If
15902 you want to allow all characters, set this value to empty.
15903 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
15906 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
15907 Username character translations before it's looked up from
15908 databases. The value contains series of from -> to characters. For
15909 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
15910 translated to @samp{@@}.
15911 Defaults to @samp{""}.
15914 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
15915 Username formatting before it's looked up from databases. You can
15916 use the standard variables here, e.g.@: %Lu would lowercase the username,
15917 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
15918 change the @samp{@@} into @samp{-AT-}. This translation is done after
15919 @samp{auth-username-translation} changes.
15920 Defaults to @samp{"%Lu"}.
15923 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
15924 If you want to allow master users to log in by specifying the master
15925 username within the normal username string (i.e.@: not using SASL
15926 mechanism's support for it), you can specify the separator character
15927 here. The format is then <username><separator><master username>.
15928 UW-IMAP uses @samp{*} as the separator, so that could be a good
15930 Defaults to @samp{""}.
15933 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
15934 Username to use for users logging in with ANONYMOUS SASL
15936 Defaults to @samp{"anonymous"}.
15939 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
15940 Maximum number of dovecot-auth worker processes. They're used to
15941 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
15942 They're automatically created and destroyed as needed.
15943 Defaults to @samp{30}.
15946 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
15947 Host name to use in GSSAPI principal names. The default is to use
15948 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
15949 allow all keytab entries.
15950 Defaults to @samp{""}.
15953 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
15954 Kerberos keytab to use for the GSSAPI mechanism. Will use the
15955 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
15956 need to change the auth service to run as root to be able to read this
15958 Defaults to @samp{""}.
15961 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
15962 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
15963 and @samp{ntlm-auth} helper.
15964 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
15965 Defaults to @samp{#f}.
15968 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
15969 Path for Samba's @samp{ntlm-auth} helper binary.
15970 Defaults to @samp{"/usr/bin/ntlm_auth"}.
15973 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
15974 Time to delay before replying to failed authentications.
15975 Defaults to @samp{"2 secs"}.
15978 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
15979 Require a valid SSL client certificate or the authentication
15981 Defaults to @samp{#f}.
15984 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
15985 Take the username from client's SSL certificate, using
15986 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
15988 Defaults to @samp{#f}.
15991 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
15992 List of wanted authentication mechanisms. Supported mechanisms are:
15993 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
15994 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
15995 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
15996 @samp{disable-plaintext-auth} setting.
15999 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
16000 List of IPs or hostnames to all director servers, including ourself.
16001 Ports can be specified as ip:port. The default port is the same as what
16002 director service's @samp{inet-listener} is using.
16003 Defaults to @samp{()}.
16006 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
16007 List of IPs or hostnames to all backend mail servers. Ranges are
16008 allowed too, like 10.0.0.10-10.0.0.30.
16009 Defaults to @samp{()}.
16012 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
16013 How long to redirect users to a specific server after it no longer
16014 has any connections.
16015 Defaults to @samp{"15 min"}.
16018 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
16019 How the username is translated before being hashed. Useful values
16020 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
16021 are shared within domain.
16022 Defaults to @samp{"%Lu"}.
16025 @deftypevr {@code{dovecot-configuration} parameter} string log-path
16026 Log file to use for error messages. @samp{syslog} logs to syslog,
16027 @samp{/dev/stderr} logs to stderr.
16028 Defaults to @samp{"syslog"}.
16031 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
16032 Log file to use for informational messages. Defaults to
16034 Defaults to @samp{""}.
16037 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
16038 Log file to use for debug messages. Defaults to
16039 @samp{info-log-path}.
16040 Defaults to @samp{""}.
16043 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
16044 Syslog facility to use if you're logging to syslog. Usually if you
16045 don't want to use @samp{mail}, you'll use local0..local7. Also other
16046 standard facilities are supported.
16047 Defaults to @samp{"mail"}.
16050 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
16051 Log unsuccessful authentication attempts and the reasons why they
16053 Defaults to @samp{#f}.
16056 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
16057 In case of password mismatches, log the attempted password. Valid
16058 values are no, plain and sha1. sha1 can be useful for detecting brute
16059 force password attempts vs. user simply trying the same password over
16060 and over again. You can also truncate the value to n chars by appending
16061 ":n" (e.g.@: sha1:6).
16062 Defaults to @samp{"no"}.
16065 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
16066 Even more verbose logging for debugging purposes. Shows for example
16068 Defaults to @samp{#f}.
16071 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
16072 In case of password mismatches, log the passwords and used scheme so
16073 the problem can be debugged. Enabling this also enables
16075 Defaults to @samp{#f}.
16078 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
16079 Enable mail process debugging. This can help you figure out why
16080 Dovecot isn't finding your mails.
16081 Defaults to @samp{#f}.
16084 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
16085 Show protocol level SSL errors.
16086 Defaults to @samp{#f}.
16089 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
16090 Prefix for each line written to log file. % codes are in
16091 strftime(3) format.
16092 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
16095 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
16096 List of elements we want to log. The elements which have a
16097 non-empty variable value are joined together to form a comma-separated
16101 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
16102 Login log format. %s contains @samp{login-log-format-elements}
16103 string, %$ contains the data we want to log.
16104 Defaults to @samp{"%$: %s"}.
16107 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
16108 Log prefix for mail processes. See doc/wiki/Variables.txt for list
16109 of possible variables you can use.
16110 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
16113 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
16114 Format to use for logging mail deliveries. You can use variables:
16117 Delivery status message (e.g.@: @samp{saved to INBOX})
16129 Defaults to @samp{"msgid=%m: %$"}.
16132 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
16133 Location for users' mailboxes. The default is empty, which means
16134 that Dovecot tries to find the mailboxes automatically. This won't work
16135 if the user doesn't yet have any mail, so you should explicitly tell
16136 Dovecot the full location.
16138 If you're using mbox, giving a path to the INBOX
16139 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
16140 where the other mailboxes are kept. This is called the "root mail
16141 directory", and it must be the first path given in the
16142 @samp{mail-location} setting.
16144 There are a few special variables you can use, eg.:
16150 user part in user@@domain, same as %u if there's no domain
16152 domain part in user@@domain, empty if there's no domain
16157 See doc/wiki/Variables.txt for full list. Some examples:
16159 @item maildir:~/Maildir
16160 @item mbox:~/mail:INBOX=/var/mail/%u
16161 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
16163 Defaults to @samp{""}.
16166 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
16167 System user and group used to access mails. If you use multiple,
16168 userdb can override these by returning uid or gid fields. You can use
16169 either numbers or names. <doc/wiki/UserIds.txt>.
16170 Defaults to @samp{""}.
16173 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
16175 Defaults to @samp{""}.
16178 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
16179 Group to enable temporarily for privileged operations. Currently
16180 this is used only with INBOX when either its initial creation or
16181 dotlocking fails. Typically this is set to "mail" to give access to
16183 Defaults to @samp{""}.
16186 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
16187 Grant access to these supplementary groups for mail processes.
16188 Typically these are used to set up access to shared mailboxes. Note
16189 that it may be dangerous to set these if users can create
16190 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
16191 could allow a user to delete others' mailboxes, or ln -s
16192 /secret/shared/box ~/mail/mybox would allow reading it).
16193 Defaults to @samp{""}.
16196 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
16197 Allow full file system access to clients. There's no access checks
16198 other than what the operating system does for the active UID/GID. It
16199 works with both maildir and mboxes, allowing you to prefix mailboxes
16200 names with e.g.@: /path/ or ~user/.
16201 Defaults to @samp{#f}.
16204 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
16205 Don't use mmap() at all. This is required if you store indexes to
16206 shared file systems (NFS or clustered file system).
16207 Defaults to @samp{#f}.
16210 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
16211 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
16212 supports @samp{O_EXCL} since version 3, so this should be safe to use
16213 nowadays by default.
16214 Defaults to @samp{#t}.
16217 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
16218 When to use fsync() or fdatasync() calls:
16221 Whenever necessary to avoid losing important data
16223 Useful with e.g.@: NFS when write()s are delayed
16225 Never use it (best performance, but crashes can lose data).
16227 Defaults to @samp{"optimized"}.
16230 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
16231 Mail storage exists in NFS. Set this to yes to make Dovecot flush
16232 NFS caches whenever needed. If you're using only a single mail server
16234 Defaults to @samp{#f}.
16237 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
16238 Mail index files also exist in NFS. Setting this to yes requires
16239 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
16240 Defaults to @samp{#f}.
16243 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
16244 Locking method for index files. Alternatives are fcntl, flock and
16245 dotlock. Dotlocking uses some tricks which may create more disk I/O
16246 than other locking methods. NFS users: flock doesn't work, remember to
16247 change @samp{mmap-disable}.
16248 Defaults to @samp{"fcntl"}.
16251 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
16252 Directory in which LDA/LMTP temporarily stores incoming mails >128
16254 Defaults to @samp{"/tmp"}.
16257 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
16258 Valid UID range for users. This is mostly to make sure that users can't
16259 log in as daemons or other system users. Note that denying root logins is
16260 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
16262 Defaults to @samp{500}.
16265 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
16267 Defaults to @samp{0}.
16270 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
16271 Valid GID range for users. Users having non-valid GID as primary group ID
16272 aren't allowed to log in. If user belongs to supplementary groups with
16273 non-valid GIDs, those groups are not set.
16274 Defaults to @samp{1}.
16277 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
16279 Defaults to @samp{0}.
16282 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
16283 Maximum allowed length for mail keyword name. It's only forced when
16284 trying to create new keywords.
16285 Defaults to @samp{50}.
16288 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
16289 List of directories under which chrooting is allowed for mail
16290 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
16291 too). This setting doesn't affect @samp{login-chroot}
16292 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
16293 "/./" in home dirs are ignored. WARNING: Never add directories here
16294 which local users can modify, that may lead to root exploit. Usually
16295 this should be done only if you don't allow shell access for users.
16296 <doc/wiki/Chrooting.txt>.
16297 Defaults to @samp{()}.
16300 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
16301 Default chroot directory for mail processes. This can be overridden
16302 for specific users in user database by giving /./ in user's home
16303 directory (e.g.@: /home/./user chroots into /home). Note that usually
16304 there is no real need to do chrooting, Dovecot doesn't allow users to
16305 access files outside their mail directory anyway. If your home
16306 directories are prefixed with the chroot directory, append "/."@: to
16307 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
16308 Defaults to @samp{""}.
16311 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
16312 UNIX socket path to master authentication server to find users.
16313 This is used by imap (for shared users) and lda.
16314 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16317 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
16318 Directory where to look up mail plugins.
16319 Defaults to @samp{"/usr/lib/dovecot"}.
16322 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
16323 List of plugins to load for all services. Plugins specific to IMAP,
16324 LDA, etc.@: are added to this list in their own .conf files.
16325 Defaults to @samp{()}.
16328 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
16329 The minimum number of mails in a mailbox before updates are done to
16330 cache file. This allows optimizing Dovecot's behavior to do less disk
16331 writes at the cost of more disk reads.
16332 Defaults to @samp{0}.
16335 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
16336 When IDLE command is running, mailbox is checked once in a while to
16337 see if there are any new mails or other changes. This setting defines
16338 the minimum time to wait between those checks. Dovecot can also use
16339 dnotify, inotify and kqueue to find out immediately when changes
16341 Defaults to @samp{"30 secs"}.
16344 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
16345 Save mails with CR+LF instead of plain LF. This makes sending those
16346 mails take less CPU, especially with sendfile() syscall with Linux and
16347 FreeBSD. But it also creates a bit more disk I/O which may just make it
16348 slower. Also note that if other software reads the mboxes/maildirs,
16349 they may handle the extra CRs wrong and cause problems.
16350 Defaults to @samp{#f}.
16353 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
16354 By default LIST command returns all entries in maildir beginning
16355 with a dot. Enabling this option makes Dovecot return only entries
16356 which are directories. This is done by stat()ing each entry, so it
16357 causes more disk I/O.
16358 (For systems setting struct @samp{dirent->d_type} this check is free
16359 and it's done always regardless of this setting).
16360 Defaults to @samp{#f}.
16363 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
16364 When copying a message, do it with hard links whenever possible.
16365 This makes the performance much better, and it's unlikely to have any
16367 Defaults to @samp{#t}.
16370 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
16371 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
16372 directory only when its mtime changes unexpectedly or when we can't find
16373 the mail otherwise.
16374 Defaults to @samp{#f}.
16377 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
16378 Which locking methods to use for locking mbox. There are four
16383 Create <mailbox>.lock file. This is the oldest and most NFS-safe
16384 solution. If you want to use /var/mail/ like directory, the users will
16385 need write access to that directory.
16387 Same as dotlock, but if it fails because of permissions or because there
16388 isn't enough disk space, just skip it.
16390 Use this if possible. Works with NFS too if lockd is used.
16392 May not exist in all systems. Doesn't work with NFS.
16394 May not exist in all systems. Doesn't work with NFS.
16397 You can use multiple locking methods; if you do the order they're declared
16398 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
16399 locking methods as well. Some operating systems don't allow using some of
16400 them simultaneously.
16403 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
16407 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
16408 Maximum time to wait for lock (all of them) before aborting.
16409 Defaults to @samp{"5 mins"}.
16412 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
16413 If dotlock exists but the mailbox isn't modified in any way,
16414 override the lock file after this much time.
16415 Defaults to @samp{"2 mins"}.
16418 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
16419 When mbox changes unexpectedly we have to fully read it to find out
16420 what changed. If the mbox is large this can take a long time. Since
16421 the change is usually just a newly appended mail, it'd be faster to
16422 simply read the new mails. If this setting is enabled, Dovecot does
16423 this but still safely fallbacks to re-reading the whole mbox file
16424 whenever something in mbox isn't how it's expected to be. The only real
16425 downside to this setting is that if some other MUA changes message
16426 flags, Dovecot doesn't notice it immediately. Note that a full sync is
16427 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
16428 Defaults to @samp{#t}.
16431 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
16432 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
16433 EXAMINE, EXPUNGE or CHECK commands. If this is set,
16434 @samp{mbox-dirty-syncs} is ignored.
16435 Defaults to @samp{#f}.
16438 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
16439 Delay writing mbox headers until doing a full write sync (EXPUNGE
16440 and CHECK commands and when closing the mailbox). This is especially
16441 useful for POP3 where clients often delete all mails. The downside is
16442 that our changes aren't immediately visible to other MUAs.
16443 Defaults to @samp{#t}.
16446 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
16447 If mbox size is smaller than this (e.g.@: 100k), don't write index
16448 files. If an index file already exists it's still read, just not
16450 Defaults to @samp{0}.
16453 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
16454 Maximum dbox file size until it's rotated.
16455 Defaults to @samp{10000000}.
16458 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
16459 Maximum dbox file age until it's rotated. Typically in days. Day
16460 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
16462 Defaults to @samp{"1d"}.
16465 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
16466 When creating new mdbox files, immediately preallocate their size to
16467 @samp{mdbox-rotate-size}. This setting currently works only in Linux
16468 with some file systems (ext4, xfs).
16469 Defaults to @samp{#f}.
16472 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
16473 sdbox and mdbox support saving mail attachments to external files,
16474 which also allows single instance storage for them. Other backends
16475 don't support this for now.
16477 WARNING: This feature hasn't been tested much yet. Use at your own risk.
16479 Directory root where to store mail attachments. Disabled, if empty.
16480 Defaults to @samp{""}.
16483 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
16484 Attachments smaller than this aren't saved externally. It's also
16485 possible to write a plugin to disable saving specific attachments
16487 Defaults to @samp{128000}.
16490 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
16491 File system backend to use for saving attachments:
16494 No SiS done by Dovecot (but this might help FS's own deduplication)
16496 SiS with immediate byte-by-byte comparison during saving
16497 @item sis-queue posix
16498 SiS with delayed comparison and deduplication.
16500 Defaults to @samp{"sis posix"}.
16503 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
16504 Hash format to use in attachment filenames. You can add any text and
16505 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
16506 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
16507 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
16508 Defaults to @samp{"%@{sha1@}"}.
16511 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
16513 Defaults to @samp{100}.
16516 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
16518 Defaults to @samp{1000}.
16521 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
16522 Default VSZ (virtual memory size) limit for service processes.
16523 This is mainly intended to catch and kill processes that leak memory
16524 before they eat up everything.
16525 Defaults to @samp{256000000}.
16528 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
16529 Login user is internally used by login processes. This is the most
16530 untrusted user in Dovecot system. It shouldn't have access to anything
16532 Defaults to @samp{"dovenull"}.
16535 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
16536 Internal user is used by unprivileged processes. It should be
16537 separate from login user, so that login processes can't disturb other
16539 Defaults to @samp{"dovecot"}.
16542 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
16543 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
16544 Defaults to @samp{"required"}.
16547 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
16548 PEM encoded X.509 SSL/TLS certificate (public key).
16549 Defaults to @samp{"</etc/dovecot/default.pem"}.
16552 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
16553 PEM encoded SSL/TLS private key. The key is opened before
16554 dropping root privileges, so keep the key file unreadable by anyone but
16556 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
16559 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
16560 If key file is password protected, give the password here.
16561 Alternatively give it when starting dovecot with -p parameter. Since
16562 this file is often world-readable, you may want to place this setting
16563 instead to a different.
16564 Defaults to @samp{""}.
16567 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
16568 PEM encoded trusted certificate authority. Set this only if you
16569 intend to use @samp{ssl-verify-client-cert? #t}. The file should
16570 contain the CA certificate(s) followed by the matching
16571 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
16572 Defaults to @samp{""}.
16575 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
16576 Require that CRL check succeeds for client certificates.
16577 Defaults to @samp{#t}.
16580 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
16581 Request client to send a certificate. If you also want to require
16582 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
16583 Defaults to @samp{#f}.
16586 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
16587 Which field from certificate to use for username. commonName and
16588 x500UniqueIdentifier are the usual choices. You'll also need to set
16589 @samp{auth-ssl-username-from-cert? #t}.
16590 Defaults to @samp{"commonName"}.
16593 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
16594 Minimum SSL protocol version to accept.
16595 Defaults to @samp{"TLSv1"}.
16598 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
16599 SSL ciphers to use.
16600 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
16603 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
16604 SSL crypto device to use, for valid values run "openssl engine".
16605 Defaults to @samp{""}.
16608 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
16609 Address to use when sending rejection mails.
16610 %d expands to recipient domain.
16611 Defaults to @samp{"postmaster@@%d"}.
16614 @deftypevr {@code{dovecot-configuration} parameter} string hostname
16615 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
16616 and in LMTP replies. Default is the system's real hostname@@domain.
16617 Defaults to @samp{""}.
16620 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
16621 If user is over quota, return with temporary failure instead of
16623 Defaults to @samp{#f}.
16626 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
16627 Binary to use for sending mails.
16628 Defaults to @samp{"/usr/sbin/sendmail"}.
16631 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
16632 If non-empty, send mails via this SMTP host[:port] instead of
16634 Defaults to @samp{""}.
16637 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
16638 Subject: header to use for rejection mails. You can use the same
16639 variables as for @samp{rejection-reason} below.
16640 Defaults to @samp{"Rejected: %s"}.
16643 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
16644 Human readable error message for rejection mails. You can use
16657 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
16660 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
16661 Delimiter character between local-part and detail in email
16663 Defaults to @samp{"+"}.
16666 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
16667 Header where the original recipient address (SMTP's RCPT TO:
16668 address) is taken from if not available elsewhere. With dovecot-lda -a
16669 parameter overrides this. A commonly used header for this is
16671 Defaults to @samp{""}.
16674 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
16675 Should saving a mail to a nonexistent mailbox automatically create
16677 Defaults to @samp{#f}.
16680 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
16681 Should automatically created mailboxes be also automatically
16683 Defaults to @samp{#f}.
16686 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
16687 Maximum IMAP command line length. Some clients generate very long
16688 command lines with huge mailboxes, so you may need to raise this if you
16689 get "Too long argument" or "IMAP command line too large" errors
16691 Defaults to @samp{64000}.
16694 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
16695 IMAP logout format string:
16698 total number of bytes read from client
16700 total number of bytes sent to client.
16702 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
16703 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@}"}.
16706 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
16707 Override the IMAP CAPABILITY response. If the value begins with '+',
16708 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
16709 Defaults to @samp{""}.
16712 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
16713 How long to wait between "OK Still here" notifications when client
16715 Defaults to @samp{"2 mins"}.
16718 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
16719 ID field names and values to send to clients. Using * as the value
16720 makes Dovecot use the default value. The following fields have default
16721 values currently: name, version, os, os-version, support-url,
16723 Defaults to @samp{""}.
16726 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
16727 ID fields sent by client to log. * means everything.
16728 Defaults to @samp{""}.
16731 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
16732 Workarounds for various client bugs:
16735 @item delay-newmail
16736 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
16737 CHECK commands. Some clients ignore them otherwise, for example OSX
16738 Mail (<v2.1). Outlook Express breaks more badly though, without this it
16739 may show user "Message no longer in server" errors. Note that OE6
16740 still breaks even with this workaround if synchronization is set to
16743 @item tb-extra-mailbox-sep
16744 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
16745 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
16746 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
16748 @item tb-lsub-flags
16749 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
16750 This makes Thunderbird realize they aren't selectable and show them
16751 greyed out, instead of only later giving "not selectable" popup error.
16753 Defaults to @samp{()}.
16756 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
16757 Host allowed in URLAUTH URLs sent by client. "*" allows all.
16758 Defaults to @samp{""}.
16762 Whew! Lots of configuration options. The nice thing about it though is
16763 that Guix has a complete interface to Dovecot's configuration
16764 language. This allows not only a nice way to declare configurations,
16765 but also offers reflective capabilities as well: users can write code to
16766 inspect and transform configurations from within Scheme.
16768 However, it could be that you just want to get a @code{dovecot.conf} up
16769 and running. In that case, you can pass an
16770 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
16771 @code{dovecot-service}. As its name indicates, an opaque configuration
16772 does not have easy reflective capabilities.
16774 Available @code{opaque-dovecot-configuration} fields are:
16776 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
16777 The dovecot package.
16780 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
16781 The contents of the @code{dovecot.conf}, as a string.
16784 For example, if your @code{dovecot.conf} is just the empty string, you
16785 could instantiate a dovecot service like this:
16788 (dovecot-service #:config
16789 (opaque-dovecot-configuration
16793 @subsubheading OpenSMTPD Service
16795 @deffn {Scheme Variable} opensmtpd-service-type
16796 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
16797 service, whose value should be an @code{opensmtpd-configuration} object
16798 as in this example:
16801 (service opensmtpd-service-type
16802 (opensmtpd-configuration
16803 (config-file (local-file "./my-smtpd.conf"))))
16807 @deftp {Data Type} opensmtpd-configuration
16808 Data type representing the configuration of opensmtpd.
16811 @item @code{package} (default: @var{opensmtpd})
16812 Package object of the OpenSMTPD SMTP server.
16814 @item @code{config-file} (default: @code{%default-opensmtpd-file})
16815 File-like object of the OpenSMTPD configuration file to use. By default
16816 it listens on the loopback network interface, and allows for mail from
16817 users and daemons on the local machine, as well as permitting email to
16818 remote servers. Run @command{man smtpd.conf} for more information.
16823 @subsubheading Exim Service
16825 @cindex mail transfer agent (MTA)
16826 @cindex MTA (mail transfer agent)
16829 @deffn {Scheme Variable} exim-service-type
16830 This is the type of the @uref{https://exim.org, Exim} mail transfer
16831 agent (MTA), whose value should be an @code{exim-configuration} object
16832 as in this example:
16835 (service exim-service-type
16836 (exim-configuration
16837 (config-file (local-file "./my-exim.conf"))))
16841 In order to use an @code{exim-service-type} service you must also have a
16842 @code{mail-aliases-service-type} service present in your
16843 @code{operating-system} (even if it has no aliases).
16845 @deftp {Data Type} exim-configuration
16846 Data type representing the configuration of exim.
16849 @item @code{package} (default: @var{exim})
16850 Package object of the Exim server.
16852 @item @code{config-file} (default: @code{#f})
16853 File-like object of the Exim configuration file to use. If its value is
16854 @code{#f} then use the default configuration file from the package
16855 provided in @code{package}. The resulting configuration file is loaded
16856 after setting the @code{exim_user} and @code{exim_group} configuration
16862 @subsubheading Getmail service
16867 @deffn {Scheme Variable} getmail-service-type
16868 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
16869 mail retriever, whose value should be an @code{getmail-configuration}.
16872 Available @code{getmail-configuration} fields are:
16874 @deftypevr {@code{getmail-configuration} parameter} symbol name
16875 A symbol to identify the getmail service.
16877 Defaults to @samp{"unset"}.
16881 @deftypevr {@code{getmail-configuration} parameter} package package
16882 The getmail package to use.
16886 @deftypevr {@code{getmail-configuration} parameter} string user
16887 The user to run getmail as.
16889 Defaults to @samp{"getmail"}.
16893 @deftypevr {@code{getmail-configuration} parameter} string group
16894 The group to run getmail as.
16896 Defaults to @samp{"getmail"}.
16900 @deftypevr {@code{getmail-configuration} parameter} string directory
16901 The getmail directory to use.
16903 Defaults to @samp{"/var/lib/getmail/default"}.
16907 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
16908 The getmail configuration file to use.
16910 Available @code{getmail-configuration-file} fields are:
16912 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
16913 What mail account to retrieve mail from, and how to access that account.
16915 Available @code{getmail-retriever-configuration} fields are:
16917 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
16918 The type of mail retriever to use. Valid values include @samp{passwd}
16921 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
16925 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
16926 Space separated list of arguments to the userdb driver.
16928 Defaults to @samp{unset}.
16932 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
16933 Space separated list of arguments to the userdb driver.
16935 Defaults to @samp{unset}.
16939 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
16940 Space separated list of arguments to the userdb driver.
16942 Defaults to @samp{#f}.
16946 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
16947 Override fields from passwd.
16949 Defaults to @samp{""}.
16953 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
16954 Override fields from passwd.
16956 Defaults to @samp{()}.
16960 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
16961 PEM-formatted key file to use for the TLS negotiation
16963 Defaults to @samp{""}.
16967 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
16968 PEM-formatted certificate file to use for the TLS negotiation
16970 Defaults to @samp{""}.
16974 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
16975 CA certificates to use
16977 Defaults to @samp{""}.
16981 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
16982 Extra retriever parameters
16984 Defaults to @samp{()}.
16990 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
16991 What to do with retrieved messages.
16993 Available @code{getmail-destination-configuration} fields are:
16995 @deftypevr {@code{getmail-destination-configuration} parameter} string type
16996 The type of mail destination. Valid values include @samp{Maildir},
16997 @samp{Mboxrd} and @samp{MDA_external}.
16999 Defaults to @samp{unset}.
17003 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
17004 The path option for the mail destination. The behaviour depends on the
17007 Defaults to @samp{""}.
17011 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
17012 Extra destination parameters
17014 Defaults to @samp{()}.
17020 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
17023 Available @code{getmail-options-configuration} fields are:
17025 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
17026 If set to @samp{0}, getmail will only print warnings and errors. A
17027 value of @samp{1} means that messages will be printed about retrieving
17028 and deleting messages. If set to @samp{2}, getmail will print messages
17029 about each of it's actions.
17031 Defaults to @samp{1}.
17035 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
17036 If true, getmail will retrieve all available messages. Otherwise it
17037 will only retrieve messages it hasn't seen previously.
17039 Defaults to @samp{#t}.
17043 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
17044 If set to true, messages will be deleted from the server after
17045 retrieving and successfully delivering them. Otherwise, messages will
17046 be left on the server.
17048 Defaults to @samp{#f}.
17052 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
17053 Getmail will delete messages this number of days after seeing them, if
17054 they have not been delivered. This means messages will be left on the
17055 server this number of days after delivering them. A value of @samp{0}
17056 disabled this feature.
17058 Defaults to @samp{0}.
17062 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
17063 Delete messages larger than this of bytes after retrieving them, even if
17064 the delete and delete-after options are disabled. A value of @samp{0}
17065 disables this feature.
17067 Defaults to @samp{0}.
17071 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
17072 Retrieve messages totalling up to this number of bytes before closing
17073 the session with the server. A value of @samp{0} disables this feature.
17075 Defaults to @samp{0}.
17079 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
17080 Don't retrieve messages larger than this number of bytes. A value of
17081 @samp{0} disables this feature.
17083 Defaults to @samp{0}.
17087 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
17088 If true, getmail will add a Delivered-To header to messages.
17090 Defaults to @samp{#t}.
17094 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
17095 If set, getmail adds a Received header to the messages.
17097 Defaults to @samp{#t}.
17101 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
17102 Getmail will record a log of its actions to the named file. A value of
17103 @samp{""} disables this feature.
17105 Defaults to @samp{""}.
17109 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
17110 If true, getmail will record a log of its actions using the system
17113 Defaults to @samp{#t}.
17117 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
17118 If true, getmail will log information about messages not retrieved and
17119 the reason for not retrieving them, as well as starting and ending
17122 Defaults to @samp{#t}.
17126 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
17127 Extra options to include.
17129 Defaults to @samp{()}.
17137 @deftypevr {@code{getmail-configuration} parameter} list idle
17138 A list of mailboxes that getmail should wait on the server for new mail
17139 notifications. This depends on the server supporting the IDLE
17142 Defaults to @samp{()}.
17146 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
17147 Environment variables to set for getmail.
17149 Defaults to @samp{()}.
17153 @subsubheading Mail Aliases Service
17155 @cindex email aliases
17156 @cindex aliases, for email addresses
17158 @deffn {Scheme Variable} mail-aliases-service-type
17159 This is the type of the service which provides @code{/etc/aliases},
17160 specifying how to deliver mail to users on this system.
17163 (service mail-aliases-service-type
17164 '(("postmaster" "bob")
17165 ("bob" "bob@@example.com" "bob@@example2.com")))
17169 The configuration for a @code{mail-aliases-service-type} service is an
17170 association list denoting how to deliver mail that comes to this
17171 system. Each entry is of the form @code{(alias addresses ...)}, with
17172 @code{alias} specifying the local alias and @code{addresses} specifying
17173 where to deliver this user's mail.
17175 The aliases aren't required to exist as users on the local system. In
17176 the above example, there doesn't need to be a @code{postmaster} entry in
17177 the @code{operating-system}'s @code{user-accounts} in order to deliver
17178 the @code{postmaster} mail to @code{bob} (which subsequently would
17179 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
17181 @subsubheading GNU Mailutils IMAP4 Daemon
17182 @cindex GNU Mailutils IMAP4 Daemon
17184 @deffn {Scheme Variable} imap4d-service-type
17185 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
17186 mailutils, GNU Mailutils Manual}), whose value should be an
17187 @code{imap4d-configuration} object as in this example:
17190 (service imap4d-service-type
17191 (imap4d-configuration
17192 (config-file (local-file "imap4d.conf"))))
17196 @deftp {Data Type} imap4d-configuration
17197 Data type representing the configuration of @command{imap4d}.
17200 @item @code{package} (default: @code{mailutils})
17201 The package that provides @command{imap4d}.
17203 @item @code{config-file} (default: @code{%default-imap4d-config-file})
17204 File-like object of the configuration file to use, by default it will listen
17205 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
17206 Mailutils Manual}, for details.
17211 @node Messaging Services
17212 @subsection Messaging Services
17217 The @code{(gnu services messaging)} module provides Guix service
17218 definitions for messaging services: currently only Prosody is supported.
17220 @subsubheading Prosody Service
17222 @deffn {Scheme Variable} prosody-service-type
17223 This is the type for the @uref{https://prosody.im, Prosody XMPP
17224 communication server}. Its value must be a @code{prosody-configuration}
17225 record as in this example:
17228 (service prosody-service-type
17229 (prosody-configuration
17230 (modules-enabled (cons "groups" "mam" %default-modules-enabled))
17233 (int-component-configuration
17234 (hostname "conference.example.net")
17236 (mod-muc (mod-muc-configuration)))))
17239 (virtualhost-configuration
17240 (domain "example.net"))))))
17243 See below for details about @code{prosody-configuration}.
17247 By default, Prosody does not need much configuration. Only one
17248 @code{virtualhosts} field is needed: it specifies the domain you wish
17251 You can perform various sanity checks on the generated configuration
17252 with the @code{prosodyctl check} command.
17254 Prosodyctl will also help you to import certificates from the
17255 @code{letsencrypt} directory so that the @code{prosody} user can access
17256 them. See @url{https://prosody.im/doc/letsencrypt}.
17259 prosodyctl --root cert import /etc/letsencrypt/live
17262 The available configuration parameters follow. Each parameter
17263 definition is preceded by its type; for example, @samp{string-list foo}
17264 indicates that the @code{foo} parameter should be specified as a list of
17265 strings. Types starting with @code{maybe-} denote parameters that won't
17266 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
17268 There is also a way to specify the configuration as a string, if you
17269 have an old @code{prosody.cfg.lua} file that you want to port over from
17270 some other system; see the end for more details.
17272 The @code{file-object} type designates either a file-like object
17273 (@pxref{G-Expressions, file-like objects}) or a file name.
17275 @c The following documentation was initially generated by
17276 @c (generate-documentation) in (gnu services messaging). Manually maintained
17277 @c documentation is better, so we shouldn't hesitate to edit below as
17278 @c needed. However if the change you want to make to this documentation
17279 @c can be done in an automated way, it's probably easier to change
17280 @c (generate-documentation) than to make it below and have to deal with
17281 @c the churn as Prosody updates.
17283 Available @code{prosody-configuration} fields are:
17285 @deftypevr {@code{prosody-configuration} parameter} package prosody
17286 The Prosody package.
17289 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
17290 Location of the Prosody data storage directory. See
17291 @url{https://prosody.im/doc/configure}.
17292 Defaults to @samp{"/var/lib/prosody"}.
17295 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
17296 Additional plugin directories. They are searched in all the specified
17297 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
17298 Defaults to @samp{()}.
17301 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
17302 Every virtual host and component needs a certificate so that clients and
17303 servers can securely verify its identity. Prosody will automatically load
17304 certificates/keys from the directory specified here.
17305 Defaults to @samp{"/etc/prosody/certs"}.
17308 @deftypevr {@code{prosody-configuration} parameter} string-list admins
17309 This is a list of accounts that are admins for the server. Note that you
17310 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
17311 @url{https://prosody.im/doc/creating_accounts}.
17312 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
17313 Defaults to @samp{()}.
17316 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
17317 Enable use of libevent for better performance under high load. See
17318 @url{https://prosody.im/doc/libevent}.
17319 Defaults to @samp{#f}.
17322 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
17323 This is the list of modules Prosody will load on startup. It looks for
17324 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
17325 Documentation on modules can be found at:
17326 @url{https://prosody.im/doc/modules}.
17327 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
17330 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
17331 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
17332 should you want to disable them then add them to this list.
17333 Defaults to @samp{()}.
17336 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
17337 Path to a text file where the shared groups are defined. If this path is
17338 empty then @samp{mod_groups} does nothing. See
17339 @url{https://prosody.im/doc/modules/mod_groups}.
17340 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
17343 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
17344 Disable account creation by default, for security. See
17345 @url{https://prosody.im/doc/creating_accounts}.
17346 Defaults to @samp{#f}.
17349 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
17350 These are the SSL/TLS-related settings. Most of them are disabled so to
17351 use Prosody's defaults. If you do not completely understand these options, do
17352 not add them to your config, it is easy to lower the security of your server
17353 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
17355 Available @code{ssl-configuration} fields are:
17357 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
17358 This determines what handshake to use.
17361 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
17362 Path to your private key file.
17365 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
17366 Path to your certificate file.
17369 @deftypevr {@code{ssl-configuration} parameter} file-object capath
17370 Path to directory containing root certificates that you wish Prosody to
17371 trust when verifying the certificates of remote servers.
17372 Defaults to @samp{"/etc/ssl/certs"}.
17375 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
17376 Path to a file containing root certificates that you wish Prosody to trust.
17377 Similar to @code{capath} but with all certificates concatenated together.
17380 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
17381 A list of verification options (these mostly map to OpenSSL's
17382 @code{set_verify()} flags).
17385 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
17386 A list of general options relating to SSL/TLS. These map to OpenSSL's
17387 @code{set_options()}. For a full list of options available in LuaSec, see the
17391 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
17392 How long a chain of certificate authorities to check when looking for a
17393 trusted root certificate.
17396 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
17397 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
17398 clients, and in what order.
17401 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
17402 A path to a file containing parameters for Diffie-Hellman key exchange. You
17403 can create such a file with:
17404 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
17407 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
17408 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
17409 @samp{"secp384r1"}.
17412 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
17413 A list of "extra" verification options.
17416 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
17417 Password for encrypted private keys.
17422 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
17423 Whether to force all client-to-server connections to be encrypted or not.
17424 See @url{https://prosody.im/doc/modules/mod_tls}.
17425 Defaults to @samp{#f}.
17428 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
17429 Set of mechanisms that will never be offered. See
17430 @url{https://prosody.im/doc/modules/mod_saslauth}.
17431 Defaults to @samp{("DIGEST-MD5")}.
17434 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
17435 Whether to force all server-to-server connections to be encrypted or not.
17436 See @url{https://prosody.im/doc/modules/mod_tls}.
17437 Defaults to @samp{#f}.
17440 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
17441 Whether to require encryption and certificate authentication. This
17442 provides ideal security, but requires servers you communicate with to support
17443 encryption AND present valid, trusted certificates. See
17444 @url{https://prosody.im/doc/s2s#security}.
17445 Defaults to @samp{#f}.
17448 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
17449 Many servers don't support encryption or have invalid or self-signed
17450 certificates. You can list domains here that will not be required to
17451 authenticate using certificates. They will be authenticated using DNS. See
17452 @url{https://prosody.im/doc/s2s#security}.
17453 Defaults to @samp{()}.
17456 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
17457 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
17458 valid certificates for some domains by specifying a list here. See
17459 @url{https://prosody.im/doc/s2s#security}.
17460 Defaults to @samp{()}.
17463 @deftypevr {@code{prosody-configuration} parameter} string authentication
17464 Select the authentication backend to use. The default provider stores
17465 passwords in plaintext and uses Prosody's configured data storage to store the
17466 authentication data. If you do not trust your server please see
17467 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
17468 about using the hashed backend. See also
17469 @url{https://prosody.im/doc/authentication}
17470 Defaults to @samp{"internal_plain"}.
17473 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
17474 Set logging options. Advanced logging configuration is not yet supported
17475 by the Prosody service. See @url{https://prosody.im/doc/logging}.
17476 Defaults to @samp{"*syslog"}.
17479 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
17480 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
17481 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
17484 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
17485 Maximum allowed size of the HTTP body (in bytes).
17488 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
17489 Some modules expose their own URL in various ways. This URL is built
17490 from the protocol, host and port used. If Prosody sits behind a proxy, the
17491 public URL will be @code{http-external-url} instead. See
17492 @url{https://prosody.im/doc/http#external_url}.
17495 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
17496 A host in Prosody is a domain on which user accounts can be created. For
17497 example if you want your users to have addresses like
17498 @samp{"john.smith@@example.com"} then you need to add a host
17499 @samp{"example.com"}. All options in this list will apply only to this host.
17501 Note: the name "virtual" host is used in configuration to avoid confusion with
17502 the actual physical host that Prosody is installed on. A single Prosody
17503 instance can serve many domains, each one defined as a VirtualHost entry in
17504 Prosody's configuration. Conversely a server that hosts a single domain would
17505 have just one VirtualHost entry.
17507 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
17509 Available @code{virtualhost-configuration} fields are:
17511 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:
17512 @deftypevr {@code{virtualhost-configuration} parameter} string domain
17513 Domain you wish Prosody to serve.
17518 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
17519 Components are extra services on a server which are available to clients,
17520 usually on a subdomain of the main server (such as
17521 @samp{"mycomponent.example.com"}). Example components might be chatroom
17522 servers, user directories, or gateways to other protocols.
17524 Internal components are implemented with Prosody-specific plugins. To add an
17525 internal component, you simply fill the hostname field, and the plugin you wish
17526 to use for the component.
17528 See @url{https://prosody.im/doc/components}.
17529 Defaults to @samp{()}.
17531 Available @code{int-component-configuration} fields are:
17533 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:
17534 @deftypevr {@code{int-component-configuration} parameter} string hostname
17535 Hostname of the component.
17538 @deftypevr {@code{int-component-configuration} parameter} string plugin
17539 Plugin you wish to use for the component.
17542 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
17543 Multi-user chat (MUC) is Prosody's module for allowing you to create
17544 hosted chatrooms/conferences for XMPP users.
17546 General information on setting up and using multi-user chatrooms can be found
17547 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
17548 which you should read if you are new to XMPP chatrooms.
17550 See also @url{https://prosody.im/doc/modules/mod_muc}.
17552 Available @code{mod-muc-configuration} fields are:
17554 @deftypevr {@code{mod-muc-configuration} parameter} string name
17555 The name to return in service discovery responses.
17556 Defaults to @samp{"Prosody Chatrooms"}.
17559 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
17560 If @samp{#t}, this will only allow admins to create new chatrooms.
17561 Otherwise anyone can create a room. The value @samp{"local"} restricts room
17562 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
17563 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
17564 restricts to service administrators only.
17565 Defaults to @samp{#f}.
17568 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
17569 Maximum number of history messages that will be sent to the member that has
17570 just joined the room.
17571 Defaults to @samp{20}.
17578 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
17579 External components use XEP-0114, which most standalone components
17580 support. To add an external component, you simply fill the hostname field. See
17581 @url{https://prosody.im/doc/components}.
17582 Defaults to @samp{()}.
17584 Available @code{ext-component-configuration} fields are:
17586 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:
17587 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
17588 Password which the component will use to log in.
17591 @deftypevr {@code{ext-component-configuration} parameter} string hostname
17592 Hostname of the component.
17597 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
17598 Port(s) Prosody listens on for component connections.
17599 Defaults to @samp{(5347)}.
17602 @deftypevr {@code{prosody-configuration} parameter} string component-interface
17603 Interface Prosody listens on for component connections.
17604 Defaults to @samp{"127.0.0.1"}.
17607 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
17608 Raw content that will be added to the configuration file.
17611 It could be that you just want to get a @code{prosody.cfg.lua}
17612 up and running. In that case, you can pass an
17613 @code{opaque-prosody-configuration} record as the value of
17614 @code{prosody-service-type}. As its name indicates, an opaque configuration
17615 does not have easy reflective capabilities.
17616 Available @code{opaque-prosody-configuration} fields are:
17618 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
17619 The prosody package.
17622 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
17623 The contents of the @code{prosody.cfg.lua} to use.
17626 For example, if your @code{prosody.cfg.lua} is just the empty
17627 string, you could instantiate a prosody service like this:
17630 (service prosody-service-type
17631 (opaque-prosody-configuration
17632 (prosody.cfg.lua "")))
17635 @c end of Prosody auto-generated documentation
17637 @subsubheading BitlBee Service
17639 @cindex IRC (Internet Relay Chat)
17640 @cindex IRC gateway
17641 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
17642 interface to a variety of messaging protocols such as XMPP.
17644 @defvr {Scheme Variable} bitlbee-service-type
17645 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
17646 gateway daemon. Its value is a @code{bitlbee-configuration} (see
17649 To have BitlBee listen on port 6667 on localhost, add this line to your
17653 (service bitlbee-service-type)
17657 @deftp {Data Type} bitlbee-configuration
17658 This is the configuration for BitlBee, with the following fields:
17661 @item @code{interface} (default: @code{"127.0.0.1"})
17662 @itemx @code{port} (default: @code{6667})
17663 Listen on the network interface corresponding to the IP address
17664 specified in @var{interface}, on @var{port}.
17666 When @var{interface} is @code{127.0.0.1}, only local clients can
17667 connect; when it is @code{0.0.0.0}, connections can come from any
17668 networking interface.
17670 @item @code{package} (default: @code{bitlbee})
17671 The BitlBee package to use.
17673 @item @code{plugins} (default: @code{'()})
17674 List of plugin packages to use---e.g., @code{bitlbee-discord}.
17676 @item @code{extra-settings} (default: @code{""})
17677 Configuration snippet added as-is to the BitlBee configuration file.
17681 @subsubheading Quassel Service
17683 @cindex IRC (Internet Relay Chat)
17684 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
17685 meaning that one or more clients can attach to and detach from the
17688 @defvr {Scheme Variable} quassel-service-type
17689 This is the service type for the @url{https://quassel-irc.org/,Quassel}
17690 IRC backend daemon. Its value is a @code{quassel-configuration}
17694 @deftp {Data Type} quassel-configuration
17695 This is the configuration for Quassel, with the following fields:
17698 @item @code{quassel} (default: @code{quassel})
17699 The Quassel package to use.
17701 @item @code{interface} (default: @code{"::,0.0.0.0"})
17702 @item @code{port} (default: @code{4242})
17703 Listen on the network interface(s) corresponding to the IPv4 or IPv6
17704 interfaces specified in the comma delimited @var{interface}, on
17707 @item @code{loglevel} (default: @code{"Info"})
17708 The level of logging desired. Accepted values are Debug, Info, Warning
17713 @node Telephony Services
17714 @subsection Telephony Services
17716 @cindex Murmur (VoIP server)
17717 @cindex VoIP server
17718 This section describes how to set up and run a Murmur server. Murmur is
17719 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
17722 @deftp {Data Type} murmur-configuration
17723 The service type for the Murmur server. An example configuration can
17727 (service murmur-service-type
17728 (murmur-configuration
17730 "Welcome to this Mumble server running on Guix!")
17731 (cert-required? #t) ;disallow text password logins
17732 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
17733 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
17736 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
17737 password with the command that is printed during the activation phase.
17739 It is recommended to register a normal Mumble user account
17740 and grant it admin or moderator rights.
17741 You can use the @code{mumble} client to
17742 login as new normal user, register yourself, and log out.
17743 For the next step login with the name @code{SuperUser} use
17744 the @code{SuperUser} password that you set previously,
17745 and grant your newly registered mumble user administrator or moderator
17746 rights and create some channels.
17748 Available @code{murmur-configuration} fields are:
17751 @item @code{package} (default: @code{mumble})
17752 Package that contains @code{bin/murmurd}.
17754 @item @code{user} (default: @code{"murmur"})
17755 User who will run the Murmur server.
17757 @item @code{group} (default: @code{"murmur"})
17758 Group of the user who will run the murmur server.
17760 @item @code{port} (default: @code{64738})
17761 Port on which the server will listen.
17763 @item @code{welcome-text} (default: @code{""})
17764 Welcome text sent to clients when they connect.
17766 @item @code{server-password} (default: @code{""})
17767 Password the clients have to enter in order to connect.
17769 @item @code{max-users} (default: @code{100})
17770 Maximum of users that can be connected to the server at once.
17772 @item @code{max-user-bandwidth} (default: @code{#f})
17773 Maximum voice traffic a user can send per second.
17775 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
17776 File name of the sqlite database.
17777 The service's user will become the owner of the directory.
17779 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
17780 File name of the log file.
17781 The service's user will become the owner of the directory.
17783 @item @code{autoban-attempts} (default: @code{10})
17784 Maximum number of logins a user can make in @code{autoban-timeframe}
17785 without getting auto banned for @code{autoban-time}.
17787 @item @code{autoban-timeframe} (default: @code{120})
17788 Timeframe for autoban in seconds.
17790 @item @code{autoban-time} (default: @code{300})
17791 Amount of time in seconds for which a client gets banned
17792 when violating the autoban limits.
17794 @item @code{opus-threshold} (default: @code{100})
17795 Percentage of clients that need to support opus
17796 before switching over to opus audio codec.
17798 @item @code{channel-nesting-limit} (default: @code{10})
17799 How deep channels can be nested at maximum.
17801 @item @code{channelname-regex} (default: @code{#f})
17802 A string in form of a Qt regular expression that channel names must conform to.
17804 @item @code{username-regex} (default: @code{#f})
17805 A string in form of a Qt regular expression that user names must conform to.
17807 @item @code{text-message-length} (default: @code{5000})
17808 Maximum size in bytes that a user can send in one text chat message.
17810 @item @code{image-message-length} (default: @code{(* 128 1024)})
17811 Maximum size in bytes that a user can send in one image message.
17813 @item @code{cert-required?} (default: @code{#f})
17814 If it is set to @code{#t} clients that use weak password authentication
17815 will not be accepted. Users must have completed the certificate wizard to join.
17817 @item @code{remember-channel?} (default: @code{#f})
17818 Should murmur remember the last channel each user was in when they disconnected
17819 and put them into the remembered channel when they rejoin.
17821 @item @code{allow-html?} (default: @code{#f})
17822 Should html be allowed in text messages, user comments, and channel descriptions.
17824 @item @code{allow-ping?} (default: @code{#f})
17825 Setting to true exposes the current user count, the maximum user count, and
17826 the server's maximum bandwidth per client to unauthenticated users. In the
17827 Mumble client, this information is shown in the Connect dialog.
17829 Disabling this setting will prevent public listing of the server.
17831 @item @code{bonjour?} (default: @code{#f})
17832 Should the server advertise itself in the local network through the bonjour protocol.
17834 @item @code{send-version?} (default: @code{#f})
17835 Should the murmur server version be exposed in ping requests.
17837 @item @code{log-days} (default: @code{31})
17838 Murmur also stores logs in the database, which are accessible via RPC.
17839 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
17840 or -1 to disable logging to the database.
17842 @item @code{obfuscate-ips?} (default: @code{#t})
17843 Should logged ips be obfuscated to protect the privacy of users.
17845 @item @code{ssl-cert} (default: @code{#f})
17846 File name of the SSL/TLS certificate used for encrypted connections.
17849 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
17851 @item @code{ssl-key} (default: @code{#f})
17852 Filepath to the ssl private key used for encrypted connections.
17854 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
17857 @item @code{ssl-dh-params} (default: @code{#f})
17858 File name of a PEM-encoded file with Diffie-Hellman parameters
17859 for the SSL/TLS encryption. Alternatively you set it to
17860 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
17861 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
17863 @item @code{ssl-ciphers} (default: @code{#f})
17864 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
17867 This option is specified using
17868 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
17869 OpenSSL cipher list notation}.
17871 It is recommended that you try your cipher string using 'openssl ciphers <string>'
17872 before setting it here, to get a feel for which cipher suites you will get.
17873 After setting this option, it is recommend that you inspect your Murmur log
17874 to ensure that Murmur is using the cipher suites that you expected it to.
17876 Note: Changing this option may impact the backwards compatibility of your
17877 Murmur server, and can remove the ability for older Mumble clients to be able
17880 @item @code{public-registration} (default: @code{#f})
17881 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
17883 You can optionally register your server in the public server list that the
17884 @code{mumble} client shows on startup.
17885 You cannot register your server if you have set a @code{server-password},
17886 or set @code{allow-ping} to @code{#f}.
17888 It might take a few hours until it shows up in the public list.
17890 @item @code{file} (default: @code{#f})
17891 Optional alternative override for this configuration.
17895 @deftp {Data Type} murmur-public-registration-configuration
17896 Configuration for public registration of a murmur service.
17900 This is a display name for your server. Not to be confused with the hostname.
17902 @item @code{password}
17903 A password to identify your registration.
17904 Subsequent updates will need the same password. Don't lose your password.
17907 This should be a @code{http://} or @code{https://} link to your web
17910 @item @code{hostname} (default: @code{#f})
17911 By default your server will be listed by its IP address.
17912 If it is set your server will be linked by this host name instead.
17918 @node Monitoring Services
17919 @subsection Monitoring Services
17921 @subsubheading Tailon Service
17923 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
17924 viewing and searching log files.
17926 The following example will configure the service with default values.
17927 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
17930 (service tailon-service-type)
17933 The following example customises more of the Tailon configuration,
17934 adding @command{sed} to the list of allowed commands.
17937 (service tailon-service-type
17938 (tailon-configuration
17940 (tailon-configuration-file
17941 (allowed-commands '("tail" "grep" "awk" "sed"))))))
17945 @deftp {Data Type} tailon-configuration
17946 Data type representing the configuration of Tailon.
17947 This type has the following parameters:
17950 @item @code{config-file} (default: @code{(tailon-configuration-file)})
17951 The configuration file to use for Tailon. This can be set to a
17952 @dfn{tailon-configuration-file} record value, or any gexp
17953 (@pxref{G-Expressions}).
17955 For example, to instead use a local file, the @code{local-file} function
17959 (service tailon-service-type
17960 (tailon-configuration
17961 (config-file (local-file "./my-tailon.conf"))))
17964 @item @code{package} (default: @code{tailon})
17965 The tailon package to use.
17970 @deftp {Data Type} tailon-configuration-file
17971 Data type representing the configuration options for Tailon.
17972 This type has the following parameters:
17975 @item @code{files} (default: @code{(list "/var/log")})
17976 List of files to display. The list can include strings for a single file
17977 or directory, or a list, where the first item is the name of a
17978 subsection, and the remaining items are the files or directories in that
17981 @item @code{bind} (default: @code{"localhost:8080"})
17982 Address and port to which Tailon should bind on.
17984 @item @code{relative-root} (default: @code{#f})
17985 URL path to use for Tailon, set to @code{#f} to not use a path.
17987 @item @code{allow-transfers?} (default: @code{#t})
17988 Allow downloading the log files in the web interface.
17990 @item @code{follow-names?} (default: @code{#t})
17991 Allow tailing of not-yet existent files.
17993 @item @code{tail-lines} (default: @code{200})
17994 Number of lines to read initially from each file.
17996 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
17997 Commands to allow running. By default, @code{sed} is disabled.
17999 @item @code{debug?} (default: @code{#f})
18000 Set @code{debug?} to @code{#t} to show debug messages.
18002 @item @code{wrap-lines} (default: @code{#t})
18003 Initial line wrapping state in the web interface. Set to @code{#t} to
18004 initially wrap lines (the default), or to @code{#f} to initially not
18007 @item @code{http-auth} (default: @code{#f})
18008 HTTP authentication type to use. Set to @code{#f} to disable
18009 authentication (the default). Supported values are @code{"digest"} or
18012 @item @code{users} (default: @code{#f})
18013 If HTTP authentication is enabled (see @code{http-auth}), access will be
18014 restricted to the credentials provided here. To configure users, use a
18015 list of pairs, where the first element of the pair is the username, and
18016 the 2nd element of the pair is the password.
18019 (tailon-configuration-file
18020 (http-auth "basic")
18021 (users '(("user1" . "password1")
18022 ("user2" . "password2"))))
18029 @subsubheading Darkstat Service
18031 Darkstat is a packet sniffer that captures network traffic, calculates
18032 statistics about usage, and serves reports over HTTP.
18034 @defvar {Scheme Variable} darkstat-service-type
18035 This is the service type for the
18036 @uref{https://unix4lyfe.org/darkstat/, darkstat}
18037 service, its value must be a @code{darkstat-configuration} record as in
18041 (service darkstat-service-type
18042 (darkstat-configuration
18043 (interface "eno1")))
18047 @deftp {Data Type} darkstat-configuration
18048 Data type representing the configuration of @command{darkstat}.
18051 @item @code{package} (default: @code{darkstat})
18052 The darkstat package to use.
18054 @item @code{interface}
18055 Capture traffic on the specified network interface.
18057 @item @code{port} (default: @code{"667"})
18058 Bind the web interface to the specified port.
18060 @item @code{bind-address} (default: @code{"127.0.0.1"})
18061 Bind the web interface to the specified address.
18063 @item @code{base} (default: @code{"/"})
18064 Specify the path of the base URL. This can be useful if
18065 @command{darkstat} is accessed via a reverse proxy.
18070 @subsubheading Prometheus Node Exporter Service
18072 @cindex prometheus-node-exporter
18073 The Prometheus ``node exporter'' makes hardware and operating system statistics
18074 provided by the Linux kernel available for the Prometheus monitoring system.
18075 This service should be deployed on all physical nodes and virtual machines,
18076 where monitoring these statistics is desirable.
18078 @defvar {Scheme variable} prometheus-node-exporter-service-type
18079 This is the service type for the
18080 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
18081 service, its value must be a @code{prometheus-node-exporter-configuration}
18082 record as in this example:
18085 (service prometheus-node-exporter-service-type
18086 (prometheus-node-exporter-configuration
18087 (web-listen-address ":9100")))
18091 @deftp {Data Type} prometheus-node-exporter-configuration
18092 Data type representing the configuration of @command{node_exporter}.
18095 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
18096 The prometheus-node-exporter package to use.
18098 @item @code{web-listen-address} (default: @code{":9100"})
18099 Bind the web interface to the specified address.
18104 @subsubheading Zabbix server
18105 @cindex zabbix zabbix-server
18106 Zabbix provides monitoring metrics, among others network utilization, CPU load
18107 and disk space consumption:
18110 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
18111 @item Auto-discovery of servers and network devices and interfaces.
18112 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
18113 @item Distributed monitoring with centralized web administration.
18114 @item Native high performance agents.
18115 @item SLA, and ITIL KPI metrics on reporting.
18116 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
18117 @item Remote command execution through Zabbix proxies.
18120 @c %start of fragment
18122 Available @code{zabbix-server-configuration} fields are:
18124 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
18125 The zabbix-server package.
18129 @deftypevr {@code{zabbix-server-configuration} parameter} string user
18130 User who will run the Zabbix server.
18132 Defaults to @samp{"zabbix"}.
18136 @deftypevr {@code{zabbix-server-configuration} parameter} group group
18137 Group who will run the Zabbix server.
18139 Defaults to @samp{"zabbix"}.
18143 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
18144 Database host name.
18146 Defaults to @samp{"127.0.0.1"}.
18150 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
18153 Defaults to @samp{"zabbix"}.
18157 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
18160 Defaults to @samp{"zabbix"}.
18164 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
18165 Database password. Please, use @code{include-files} with
18166 @code{DBPassword=SECRET} inside a specified file instead.
18168 Defaults to @samp{""}.
18172 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
18175 Defaults to @samp{5432}.
18179 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
18180 Specifies where log messages are written to:
18184 @code{system} - syslog.
18187 @code{file} - file specified with @code{log-file} parameter.
18190 @code{console} - standard output.
18194 Defaults to @samp{""}.
18198 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
18199 Log file name for @code{log-type} @code{file} parameter.
18201 Defaults to @samp{"/var/log/zabbix/server.log"}.
18205 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
18208 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
18212 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
18213 The location of certificate authority (CA) files for SSL server
18214 certificate verification.
18216 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
18220 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
18221 Location of SSL client certificates.
18223 Defaults to @samp{"/etc/ssl/certs"}.
18227 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
18228 Extra options will be appended to Zabbix server configuration file.
18230 Defaults to @samp{""}.
18234 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
18235 You may include individual files or all files in a directory in the
18236 configuration file.
18238 Defaults to @samp{()}.
18242 @c %end of fragment
18244 @subsubheading Zabbix agent
18245 @cindex zabbix zabbix-agent
18247 Zabbix agent gathers information for Zabbix server.
18249 @c %start of fragment
18251 Available @code{zabbix-agent-configuration} fields are:
18253 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
18254 The zabbix-agent package.
18258 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
18259 User who will run the Zabbix agent.
18261 Defaults to @samp{"zabbix"}.
18265 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
18266 Group who will run the Zabbix agent.
18268 Defaults to @samp{"zabbix"}.
18272 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
18273 Unique, case sensitive hostname which is required for active checks and
18274 must match hostname as configured on the server.
18276 Defaults to @samp{"Zabbix server"}.
18280 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
18281 Specifies where log messages are written to:
18285 @code{system} - syslog.
18288 @code{file} - file specified with @code{log-file} parameter.
18291 @code{console} - standard output.
18295 Defaults to @samp{""}.
18299 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
18300 Log file name for @code{log-type} @code{file} parameter.
18302 Defaults to @samp{"/var/log/zabbix/agent.log"}.
18306 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
18309 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
18313 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
18314 List of IP addresses, optionally in CIDR notation, or hostnames of
18315 Zabbix servers and Zabbix proxies. Incoming connections will be
18316 accepted only from the hosts listed here.
18318 Defaults to @samp{("127.0.0.1")}.
18322 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
18323 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
18324 proxies for active checks. If port is not specified, default port is
18325 used. If this parameter is not specified, active checks are disabled.
18327 Defaults to @samp{("127.0.0.1")}.
18331 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
18332 Extra options will be appended to Zabbix server configuration file.
18334 Defaults to @samp{""}.
18338 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
18339 You may include individual files or all files in a directory in the
18340 configuration file.
18342 Defaults to @samp{()}.
18346 @c %end of fragment
18348 @subsubheading Zabbix front-end
18349 @cindex zabbix zabbix-front-end
18351 This service provides a WEB interface to Zabbix server.
18353 @c %start of fragment
18355 Available @code{zabbix-front-end-configuration} fields are:
18357 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
18358 NGINX configuration.
18362 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
18363 Database host name.
18365 Defaults to @samp{"localhost"}.
18369 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
18372 Defaults to @samp{5432}.
18376 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
18379 Defaults to @samp{"zabbix"}.
18383 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
18386 Defaults to @samp{"zabbix"}.
18390 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
18391 Database password. Please, use @code{db-secret-file} instead.
18393 Defaults to @samp{""}.
18397 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
18398 Secret file which will be appended to @file{zabbix.conf.php} file. This
18399 file contains credentials for use by Zabbix front-end. You are expected
18400 to create it manually.
18402 Defaults to @samp{""}.
18406 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
18407 Zabbix server hostname.
18409 Defaults to @samp{"localhost"}.
18413 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
18414 Zabbix server port.
18416 Defaults to @samp{10051}.
18421 @c %end of fragment
18423 @node Kerberos Services
18424 @subsection Kerberos Services
18427 The @code{(gnu services kerberos)} module provides services relating to
18428 the authentication protocol @dfn{Kerberos}.
18430 @subsubheading Krb5 Service
18432 Programs using a Kerberos client library normally
18433 expect a configuration file in @file{/etc/krb5.conf}.
18434 This service generates such a file from a definition provided in the
18435 operating system declaration.
18436 It does not cause any daemon to be started.
18438 No ``keytab'' files are provided by this service---you must explicitly create them.
18439 This service is known to work with the MIT client library, @code{mit-krb5}.
18440 Other implementations have not been tested.
18442 @defvr {Scheme Variable} krb5-service-type
18443 A service type for Kerberos 5 clients.
18447 Here is an example of its use:
18449 (service krb5-service-type
18450 (krb5-configuration
18451 (default-realm "EXAMPLE.COM")
18452 (allow-weak-crypto? #t)
18455 (name "EXAMPLE.COM")
18456 (admin-server "groucho.example.com")
18457 (kdc "karl.example.com"))
18460 (admin-server "kerb-admin.argrx.edu")
18461 (kdc "keys.argrx.edu"))))))
18465 This example provides a Kerberos@tie{}5 client configuration which:
18467 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
18468 of which have distinct administration servers and key distribution centers;
18469 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
18470 specified by clients;
18471 @item Accepts services which only support encryption types known to be weak.
18474 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
18475 Only the most commonly used ones are described here.
18476 For a full list, and more detailed explanation of each, see the MIT
18477 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
18481 @deftp {Data Type} krb5-realm
18482 @cindex realm, kerberos
18485 This field is a string identifying the name of the realm.
18486 A common convention is to use the fully qualified DNS name of your organization,
18487 converted to upper case.
18489 @item @code{admin-server}
18490 This field is a string identifying the host where the administration server is
18494 This field is a string identifying the key distribution center
18499 @deftp {Data Type} krb5-configuration
18502 @item @code{allow-weak-crypto?} (default: @code{#f})
18503 If this flag is @code{#t} then services which only offer encryption algorithms
18504 known to be weak will be accepted.
18506 @item @code{default-realm} (default: @code{#f})
18507 This field should be a string identifying the default Kerberos
18508 realm for the client.
18509 You should set this field to the name of your Kerberos realm.
18510 If this value is @code{#f}
18511 then a realm must be specified with every Kerberos principal when invoking programs
18512 such as @command{kinit}.
18514 @item @code{realms}
18515 This should be a non-empty list of @code{krb5-realm} objects, which clients may
18517 Normally, one of them will have a @code{name} field matching the @code{default-realm}
18523 @subsubheading PAM krb5 Service
18526 The @code{pam-krb5} service allows for login authentication and password
18527 management via Kerberos.
18528 You will need this service if you want PAM enabled applications to authenticate
18529 users using Kerberos.
18531 @defvr {Scheme Variable} pam-krb5-service-type
18532 A service type for the Kerberos 5 PAM module.
18535 @deftp {Data Type} pam-krb5-configuration
18536 Data type representing the configuration of the Kerberos 5 PAM module.
18537 This type has the following parameters:
18539 @item @code{pam-krb5} (default: @code{pam-krb5})
18540 The pam-krb5 package to use.
18542 @item @code{minimum-uid} (default: @code{1000})
18543 The smallest user ID for which Kerberos authentications should be attempted.
18544 Local accounts with lower values will silently fail to authenticate.
18549 @node LDAP Services
18550 @subsection LDAP Services
18552 @cindex nslcd, LDAP service
18554 The @code{(gnu services authentication)} module provides the
18555 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
18556 server. In addition to configuring the service itself, you may want to add
18557 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
18558 Switch} for detailed information.
18560 Here is a simple operating system declaration with a default configuration of
18561 the @code{nslcd-service-type} and a Name Service Switch configuration that
18562 consults the @code{ldap} name service last:
18565 (use-service-modules authentication)
18566 (use-modules (gnu system nss))
18572 (service nslcd-service-type)
18573 (service dhcp-client-service-type)
18575 (name-service-switch
18576 (let ((services (list (name-service (name "db"))
18577 (name-service (name "files"))
18578 (name-service (name "ldap")))))
18579 (name-service-switch
18580 (inherit %mdns-host-lookup-nss)
18581 (password services)
18584 (netgroup services)
18585 (gshadow services)))))
18588 @c %start of generated documentation for nslcd-configuration
18590 Available @code{nslcd-configuration} fields are:
18592 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
18593 The @code{nss-pam-ldapd} package to use.
18597 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
18598 The number of threads to start that can handle requests and perform LDAP
18599 queries. Each thread opens a separate connection to the LDAP server.
18600 The default is to start 5 threads.
18602 Defaults to @samp{disabled}.
18606 @deftypevr {@code{nslcd-configuration} parameter} string uid
18607 This specifies the user id with which the daemon should be run.
18609 Defaults to @samp{"nslcd"}.
18613 @deftypevr {@code{nslcd-configuration} parameter} string gid
18614 This specifies the group id with which the daemon should be run.
18616 Defaults to @samp{"nslcd"}.
18620 @deftypevr {@code{nslcd-configuration} parameter} log-option log
18621 This option controls the way logging is done via a list containing
18622 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
18623 or "syslog", or an absolute file name. The LEVEL argument is optional
18624 and specifies the log level. The log level may be one of the following
18625 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
18626 messages with the specified log level or higher are logged.
18628 Defaults to @samp{("/var/log/nslcd" info)}.
18632 @deftypevr {@code{nslcd-configuration} parameter} list uri
18633 The list of LDAP server URIs. Normally, only the first server will be
18634 used with the following servers as fall-back.
18636 Defaults to @samp{("ldap://localhost:389/")}.
18640 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
18641 The version of the LDAP protocol to use. The default is to use the
18642 maximum version supported by the LDAP library.
18644 Defaults to @samp{disabled}.
18648 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
18649 Specifies the distinguished name with which to bind to the directory
18650 server for lookups. The default is to bind anonymously.
18652 Defaults to @samp{disabled}.
18656 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
18657 Specifies the credentials with which to bind. This option is only
18658 applicable when used with binddn.
18660 Defaults to @samp{disabled}.
18664 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
18665 Specifies the distinguished name to use when the root user tries to
18666 modify a user's password using the PAM module.
18668 Defaults to @samp{disabled}.
18672 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
18673 Specifies the credentials with which to bind if the root user tries to
18674 change a user's password. This option is only applicable when used with
18677 Defaults to @samp{disabled}.
18681 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
18682 Specifies the SASL mechanism to be used when performing SASL
18685 Defaults to @samp{disabled}.
18689 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
18690 Specifies the SASL realm to be used when performing SASL authentication.
18692 Defaults to @samp{disabled}.
18696 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
18697 Specifies the authentication identity to be used when performing SASL
18700 Defaults to @samp{disabled}.
18704 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
18705 Specifies the authorization identity to be used when performing SASL
18708 Defaults to @samp{disabled}.
18712 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
18713 Determines whether the LDAP server host name should be canonicalised. If
18714 this is enabled the LDAP library will do a reverse host name lookup. By
18715 default, it is left up to the LDAP library whether this check is
18718 Defaults to @samp{disabled}.
18722 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
18723 Set the name for the GSS-API Kerberos credentials cache.
18725 Defaults to @samp{disabled}.
18729 @deftypevr {@code{nslcd-configuration} parameter} string base
18730 The directory search base.
18732 Defaults to @samp{"dc=example,dc=com"}.
18736 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
18737 Specifies the search scope (subtree, onelevel, base or children). The
18738 default scope is subtree; base scope is almost never useful for name
18739 service lookups; children scope is not supported on all servers.
18741 Defaults to @samp{(subtree)}.
18745 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
18746 Specifies the policy for dereferencing aliases. The default policy is
18747 to never dereference aliases.
18749 Defaults to @samp{disabled}.
18753 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
18754 Specifies whether automatic referral chasing should be enabled. The
18755 default behaviour is to chase referrals.
18757 Defaults to @samp{disabled}.
18761 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
18762 This option allows for custom attributes to be looked up instead of the
18763 default RFC 2307 attributes. It is a list of maps, each consisting of
18764 the name of a map, the RFC 2307 attribute to match and the query
18765 expression for the attribute as it is available in the directory.
18767 Defaults to @samp{()}.
18771 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
18772 A list of filters consisting of the name of a map to which the filter
18773 applies and an LDAP search filter expression.
18775 Defaults to @samp{()}.
18779 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
18780 Specifies the time limit in seconds to use when connecting to the
18781 directory server. The default value is 10 seconds.
18783 Defaults to @samp{disabled}.
18787 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
18788 Specifies the time limit (in seconds) to wait for a response from the
18789 LDAP server. A value of zero, which is the default, is to wait
18790 indefinitely for searches to be completed.
18792 Defaults to @samp{disabled}.
18796 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
18797 Specifies the period if inactivity (in seconds) after which the con‐
18798 nection to the LDAP server will be closed. The default is not to time
18801 Defaults to @samp{disabled}.
18805 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
18806 Specifies the number of seconds to sleep when connecting to all LDAP
18807 servers fails. By default one second is waited between the first
18808 failure and the first retry.
18810 Defaults to @samp{disabled}.
18814 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
18815 Specifies the time after which the LDAP server is considered to be
18816 permanently unavailable. Once this time is reached retries will be done
18817 only once per this time period. The default value is 10 seconds.
18819 Defaults to @samp{disabled}.
18823 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
18824 Specifies whether to use SSL/TLS or not (the default is not to). If
18825 'start-tls is specified then StartTLS is used rather than raw LDAP over
18828 Defaults to @samp{disabled}.
18832 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
18833 Specifies what checks to perform on a server-supplied certificate. The
18834 meaning of the values is described in the ldap.conf(5) manual page.
18836 Defaults to @samp{disabled}.
18840 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
18841 Specifies the directory containing X.509 certificates for peer authen‐
18842 tication. This parameter is ignored when using GnuTLS.
18844 Defaults to @samp{disabled}.
18848 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
18849 Specifies the path to the X.509 certificate for peer authentication.
18851 Defaults to @samp{disabled}.
18855 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
18856 Specifies the path to an entropy source. This parameter is ignored when
18859 Defaults to @samp{disabled}.
18863 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
18864 Specifies the ciphers to use for TLS as a string.
18866 Defaults to @samp{disabled}.
18870 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
18871 Specifies the path to the file containing the local certificate for
18872 client TLS authentication.
18874 Defaults to @samp{disabled}.
18878 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
18879 Specifies the path to the file containing the private key for client TLS
18882 Defaults to @samp{disabled}.
18886 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
18887 Set this to a number greater than 0 to request paged results from the
18888 LDAP server in accordance with RFC2696. The default (0) is to not
18889 request paged results.
18891 Defaults to @samp{disabled}.
18895 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
18896 This option prevents group membership lookups through LDAP for the
18897 specified users. Alternatively, the value 'all-local may be used. With
18898 that value nslcd builds a full list of non-LDAP users on startup.
18900 Defaults to @samp{disabled}.
18904 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
18905 This option ensures that LDAP users with a numeric user id lower than
18906 the specified value are ignored.
18908 Defaults to @samp{disabled}.
18912 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
18913 This option specifies an offset that is added to all LDAP numeric user
18914 ids. This can be used to avoid user id collisions with local users.
18916 Defaults to @samp{disabled}.
18920 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
18921 This option specifies an offset that is added to all LDAP numeric group
18922 ids. This can be used to avoid user id collisions with local groups.
18924 Defaults to @samp{disabled}.
18928 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
18929 If this option is set, the member attribute of a group may point to
18930 another group. Members of nested groups are also returned in the higher
18931 level group and parent groups are returned when finding groups for a
18932 specific user. The default is not to perform extra searches for nested
18935 Defaults to @samp{disabled}.
18939 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
18940 If this option is set, the group member list is not retrieved when
18941 looking up groups. Lookups for finding which groups a user belongs to
18942 will remain functional so the user will likely still get the correct
18943 groups assigned on login.
18945 Defaults to @samp{disabled}.
18949 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
18950 If this option is set, functions which cause all user/group entries to
18951 be loaded from the directory will not succeed in doing so. This can
18952 dramatically reduce LDAP server load in situations where there are a
18953 great number of users and/or groups. This option is not recommended for
18954 most configurations.
18956 Defaults to @samp{disabled}.
18960 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
18961 This option can be used to specify how user and group names are verified
18962 within the system. This pattern is used to check all user and group
18963 names that are requested and returned from LDAP.
18965 Defaults to @samp{disabled}.
18969 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
18970 This specifies whether or not to perform searches using case-insensitive
18971 matching. Enabling this could open up the system to authorization
18972 bypass vulnerabilities and introduce nscd cache poisoning
18973 vulnerabilities which allow denial of service.
18975 Defaults to @samp{disabled}.
18979 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
18980 This option specifies whether password policy controls are requested and
18981 handled from the LDAP server when performing user authentication.
18983 Defaults to @samp{disabled}.
18987 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
18988 By default nslcd performs an LDAP search with the user's credentials
18989 after BIND (authentication) to ensure that the BIND operation was
18990 successful. The default search is a simple check to see if the user's
18991 DN exists. A search filter can be specified that will be used instead.
18992 It should return at least one entry.
18994 Defaults to @samp{disabled}.
18998 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
18999 This option allows flexible fine tuning of the authorisation check that
19000 should be performed. The search filter specified is executed and if any
19001 entries match, access is granted, otherwise access is denied.
19003 Defaults to @samp{disabled}.
19007 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
19008 If this option is set password modification using pam_ldap will be
19009 denied and the specified message will be presented to the user instead.
19010 The message can be used to direct the user to an alternative means of
19011 changing their password.
19013 Defaults to @samp{disabled}.
19017 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
19018 List of pam service names for which LDAP authentication should suffice.
19020 Defaults to @samp{()}.
19024 @c %end of generated documentation for nslcd-configuration
19028 @subsection Web Services
19033 The @code{(gnu services web)} module provides the Apache HTTP Server,
19034 the nginx web server, and also a fastcgi wrapper daemon.
19036 @subsubheading Apache HTTP Server
19038 @deffn {Scheme Variable} httpd-service-type
19039 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
19040 (@dfn{httpd}). The value for this service type is a
19041 @code{httpd-configuration} record.
19043 A simple example configuration is given below.
19046 (service httpd-service-type
19047 (httpd-configuration
19050 (server-name "www.example.com")
19051 (document-root "/srv/http/www.example.com")))))
19054 Other services can also extend the @code{httpd-service-type} to add to
19058 (simple-service 'my-extra-server httpd-service-type
19062 (list (string-append
19063 "ServerName "www.example.com
19064 DocumentRoot \"/srv/http/www.example.com\"")))))
19068 The details for the @code{httpd-configuration}, @code{httpd-module},
19069 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
19072 @deffn {Data Type} httpd-configuration
19073 This data type represents the configuration for the httpd service.
19076 @item @code{package} (default: @code{httpd})
19077 The httpd package to use.
19079 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19080 The pid file used by the shepherd-service.
19082 @item @code{config} (default: @code{(httpd-config-file)})
19083 The configuration file to use with the httpd service. The default value
19084 is a @code{httpd-config-file} record, but this can also be a different
19085 G-expression that generates a file, for example a @code{plain-file}. A
19086 file outside of the store can also be specified through a string.
19091 @deffn {Data Type} httpd-module
19092 This data type represents a module for the httpd service.
19096 The name of the module.
19099 The file for the module. This can be relative to the httpd package being
19100 used, the absolute location of a file, or a G-expression for a file
19101 within the store, for example @code{(file-append mod-wsgi
19102 "/modules/mod_wsgi.so")}.
19107 @defvr {Scheme Variable} %default-httpd-modules
19108 A default list of @code{httpd-module} objects.
19111 @deffn {Data Type} httpd-config-file
19112 This data type represents a configuration file for the httpd service.
19115 @item @code{modules} (default: @code{%default-httpd-modules})
19116 The modules to load. Additional modules can be added here, or loaded by
19117 additional configuration.
19119 For example, in order to handle requests for PHP files, you can use Apache’s
19120 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
19123 (service httpd-service-type
19124 (httpd-configuration
19129 (name "proxy_module")
19130 (file "modules/mod_proxy.so"))
19132 (name "proxy_fcgi_module")
19133 (file "modules/mod_proxy_fcgi.so"))
19134 %default-httpd-modules))
19135 (extra-config (list "\
19136 <FilesMatch \\.php$>
19137 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
19138 </FilesMatch>"))))))
19139 (service php-fpm-service-type
19140 (php-fpm-configuration
19141 (socket "/var/run/php-fpm.sock")
19142 (socket-group "httpd")))
19145 @item @code{server-root} (default: @code{httpd})
19146 The @code{ServerRoot} in the configuration file, defaults to the httpd
19147 package. Directives including @code{Include} and @code{LoadModule} are
19148 taken as relative to the server root.
19150 @item @code{server-name} (default: @code{#f})
19151 The @code{ServerName} in the configuration file, used to specify the
19152 request scheme, hostname and port that the server uses to identify
19155 This doesn't need to be set in the server config, and can be specifyed
19156 in virtual hosts. The default is @code{#f} to not specify a
19159 @item @code{document-root} (default: @code{"/srv/http"})
19160 The @code{DocumentRoot} from which files will be served.
19162 @item @code{listen} (default: @code{'("80")})
19163 The list of values for the @code{Listen} directives in the config
19164 file. The value should be a list of strings, when each string can
19165 specify the port number to listen on, and optionally the IP address and
19168 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19169 The @code{PidFile} to use. This should match the @code{pid-file} set in
19170 the @code{httpd-configuration} so that the Shepherd service is
19171 configured correctly.
19173 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
19174 The @code{ErrorLog} to which the server will log errors.
19176 @item @code{user} (default: @code{"httpd"})
19177 The @code{User} which the server will answer requests as.
19179 @item @code{group} (default: @code{"httpd"})
19180 The @code{Group} which the server will answer requests as.
19182 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
19183 A flat list of strings and G-expressions which will be added to the end
19184 of the configuration file.
19186 Any values which the service is extended with will be appended to this
19192 @deffn {Data Type} httpd-virtualhost
19193 This data type represents a virtualhost configuration block for the httpd service.
19195 These should be added to the extra-config for the httpd-service.
19198 (simple-service 'my-extra-server httpd-service-type
19202 (list (string-append
19203 "ServerName "www.example.com
19204 DocumentRoot \"/srv/http/www.example.com\"")))))
19208 @item @code{addresses-and-ports}
19209 The addresses and ports for the @code{VirtualHost} directive.
19211 @item @code{contents}
19212 The contents of the @code{VirtualHost} directive, this should be a list
19213 of strings and G-expressions.
19218 @subsubheading NGINX
19220 @deffn {Scheme Variable} nginx-service-type
19221 Service type for the @uref{https://nginx.org/,NGinx} web server. The
19222 value for this service type is a @code{<nginx-configuration>} record.
19224 A simple example configuration is given below.
19227 (service nginx-service-type
19228 (nginx-configuration
19230 (list (nginx-server-configuration
19231 (server-name '("www.example.com"))
19232 (root "/srv/http/www.example.com"))))))
19235 In addition to adding server blocks to the service configuration
19236 directly, this service can be extended by other services to add server
19237 blocks, as in this example:
19240 (simple-service 'my-extra-server nginx-service-type
19241 (list (nginx-server-configuration
19242 (root "/srv/http/extra-website")
19243 (try-files (list "$uri" "$uri/index.html")))))
19247 At startup, @command{nginx} has not yet read its configuration file, so
19248 it uses a default file to log error messages. If it fails to load its
19249 configuration file, that is where error messages are logged. After the
19250 configuration file is loaded, the default error log file changes as per
19251 configuration. In our case, startup error messages can be found in
19252 @file{/var/run/nginx/logs/error.log}, and after configuration in
19253 @file{/var/log/nginx/error.log}. The second location can be changed
19254 with the @var{log-directory} configuration option.
19256 @deffn {Data Type} nginx-configuration
19257 This data type represents the configuration for NGinx. Some
19258 configuration can be done through this and the other provided record
19259 types, or alternatively, a config file can be provided.
19262 @item @code{nginx} (default: @code{nginx})
19263 The nginx package to use.
19265 @item @code{log-directory} (default: @code{"/var/log/nginx"})
19266 The directory to which NGinx will write log files.
19268 @item @code{run-directory} (default: @code{"/var/run/nginx"})
19269 The directory in which NGinx will create a pid file, and write temporary
19272 @item @code{server-blocks} (default: @code{'()})
19273 A list of @dfn{server blocks} to create in the generated configuration
19274 file, the elements should be of type
19275 @code{<nginx-server-configuration>}.
19277 The following example would setup NGinx to serve @code{www.example.com}
19278 from the @code{/srv/http/www.example.com} directory, without using
19281 (service nginx-service-type
19282 (nginx-configuration
19284 (list (nginx-server-configuration
19285 (server-name '("www.example.com"))
19286 (root "/srv/http/www.example.com"))))))
19289 @item @code{upstream-blocks} (default: @code{'()})
19290 A list of @dfn{upstream blocks} to create in the generated configuration
19291 file, the elements should be of type
19292 @code{<nginx-upstream-configuration>}.
19294 Configuring upstreams through the @code{upstream-blocks} can be useful
19295 when combined with @code{locations} in the
19296 @code{<nginx-server-configuration>} records. The following example
19297 creates a server configuration with one location configuration, that
19298 will proxy requests to a upstream configuration, which will handle
19299 requests with two servers.
19304 (nginx-configuration
19306 (list (nginx-server-configuration
19307 (server-name '("www.example.com"))
19308 (root "/srv/http/www.example.com")
19311 (nginx-location-configuration
19313 (body '("proxy_pass http://server-proxy;"))))))))
19315 (list (nginx-upstream-configuration
19316 (name "server-proxy")
19317 (servers (list "server1.example.com"
19318 "server2.example.com")))))))
19321 @item @code{file} (default: @code{#f})
19322 If a configuration @var{file} is provided, this will be used, rather than
19323 generating a configuration file from the provided @code{log-directory},
19324 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
19325 proper operation, these arguments should match what is in @var{file} to ensure
19326 that the directories are created when the service is activated.
19328 This can be useful if you have an existing configuration file, or it's
19329 not possible to do what is required through the other parts of the
19330 nginx-configuration record.
19332 @item @code{server-names-hash-bucket-size} (default: @code{#f})
19333 Bucket size for the server names hash tables, defaults to @code{#f} to
19334 use the size of the processors cache line.
19336 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
19337 Maximum bucket size for the server names hash tables.
19339 @item @code{extra-content} (default: @code{""})
19340 Extra content for the @code{http} block. Should be string or a string
19341 valued G-expression.
19346 @deftp {Data Type} nginx-server-configuration
19347 Data type representing the configuration of an nginx server block.
19348 This type has the following parameters:
19351 @item @code{listen} (default: @code{'("80" "443 ssl")})
19352 Each @code{listen} directive sets the address and port for IP, or the
19353 path for a UNIX-domain socket on which the server will accept requests.
19354 Both address and port, or only address or only port can be specified.
19355 An address may also be a hostname, for example:
19358 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
19361 @item @code{server-name} (default: @code{(list 'default)})
19362 A list of server names this server represents. @code{'default} represents the
19363 default server for connections matching no other server.
19365 @item @code{root} (default: @code{"/srv/http"})
19366 Root of the website nginx will serve.
19368 @item @code{locations} (default: @code{'()})
19369 A list of @dfn{nginx-location-configuration} or
19370 @dfn{nginx-named-location-configuration} records to use within this
19373 @item @code{index} (default: @code{(list "index.html")})
19374 Index files to look for when clients ask for a directory. If it cannot be found,
19375 Nginx will send the list of files in the directory.
19377 @item @code{try-files} (default: @code{'()})
19378 A list of files whose existence is checked in the specified order.
19379 @code{nginx} will use the first file it finds to process the request.
19381 @item @code{ssl-certificate} (default: @code{#f})
19382 Where to find the certificate for secure connections. Set it to @code{#f} if
19383 you don't have a certificate or you don't want to use HTTPS.
19385 @item @code{ssl-certificate-key} (default: @code{#f})
19386 Where to find the private key for secure connections. Set it to @code{#f} if
19387 you don't have a key or you don't want to use HTTPS.
19389 @item @code{server-tokens?} (default: @code{#f})
19390 Whether the server should add its configuration to response.
19392 @item @code{raw-content} (default: @code{'()})
19393 A list of raw lines added to the server block.
19398 @deftp {Data Type} nginx-upstream-configuration
19399 Data type representing the configuration of an nginx @code{upstream}
19400 block. This type has the following parameters:
19404 Name for this group of servers.
19406 @item @code{servers}
19407 Specify the addresses of the servers in the group. The address can be
19408 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
19409 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
19410 prefix @samp{unix:}. For addresses using an IP address or domain name,
19411 the default port is 80, and a different port can be specified
19417 @deftp {Data Type} nginx-location-configuration
19418 Data type representing the configuration of an nginx @code{location}
19419 block. This type has the following parameters:
19423 URI which this location block matches.
19425 @anchor{nginx-location-configuration body}
19427 Body of the location block, specified as a list of strings. This can contain
19429 configuration directives. For example, to pass requests to a upstream
19430 server group defined using an @code{nginx-upstream-configuration} block,
19431 the following directive would be specified in the body @samp{(list "proxy_pass
19432 http://upstream-name;")}.
19437 @deftp {Data Type} nginx-named-location-configuration
19438 Data type representing the configuration of an nginx named location
19439 block. Named location blocks are used for request redirection, and not
19440 used for regular request processing. This type has the following
19445 Name to identify this location block.
19448 @xref{nginx-location-configuration body}, as the body for named location
19449 blocks can be used in a similar way to the
19450 @code{nginx-location-configuration body}. One restriction is that the
19451 body of a named location block cannot contain location blocks.
19456 @subsubheading Varnish Cache
19458 Varnish is a fast cache server that sits in between web applications
19459 and end users. It proxies requests from clients and caches the
19460 accessed URLs such that multiple requests for the same resource only
19461 creates one request to the back-end.
19463 @defvr {Scheme Variable} varnish-service-type
19464 Service type for the Varnish daemon.
19467 @deftp {Data Type} varnish-configuration
19468 Data type representing the @code{varnish} service configuration.
19469 This type has the following parameters:
19472 @item @code{package} (default: @code{varnish})
19473 The Varnish package to use.
19475 @item @code{name} (default: @code{"default"})
19476 A name for this Varnish instance. Varnish will create a directory in
19477 @file{/var/varnish/} with this name and keep temporary files there. If
19478 the name starts with a forward slash, it is interpreted as an absolute
19481 Pass the @code{-n} argument to other Varnish programs to connect to the
19482 named instance, e.g.@: @command{varnishncsa -n default}.
19484 @item @code{backend} (default: @code{"localhost:8080"})
19485 The backend to use. This option has no effect if @code{vcl} is set.
19487 @item @code{vcl} (default: #f)
19488 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
19489 is @code{#f}, Varnish will proxy @code{backend} using the default
19490 configuration. Otherwise this must be a file-like object with valid
19493 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
19494 For example, to mirror @url{http://www.gnu.org,www.gnu.org} with VCL you
19495 can do something along these lines:
19498 (define %gnu-mirror
19502 backend gnu @{ .host = "www.gnu.org"; @}"))
19506 (services (cons (service varnish-service-type
19507 (varnish-configuration
19509 (vcl %gnu-mirror)))
19513 The configuration of an already running Varnish instance can be inspected
19514 and changed using the @command{varnishadm} program.
19516 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
19517 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
19518 comprehensive documentation on Varnish and its configuration language.
19520 @item @code{listen} (default: @code{'("localhost:80")})
19521 List of addresses Varnish will listen on.
19523 @item @code{storage} (default: @code{'("malloc,128m")})
19524 List of storage backends that will be available in VCL.
19526 @item @code{parameters} (default: @code{'()})
19527 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
19529 @item @code{extra-options} (default: @code{'()})
19530 Additional arguments to pass to the @command{varnishd} process.
19535 @subsubheading Patchwork
19537 Patchwork is a patch tracking system. It can collect patches sent to a
19538 mailing list, and display them in a web interface.
19540 @defvr {Scheme Variable} patchwork-service-type
19541 Service type for Patchwork.
19544 The following example is an example of a minimal service for Patchwork, for
19545 the @code{patchwork.example.com} domain.
19548 (service patchwork-service-type
19549 (patchwork-configuration
19550 (domain "patchwork.example.com")
19552 (patchwork-settings-module
19553 (allowed-hosts (list domain))
19554 (default-from-email "patchwork@@patchwork.example.com")))
19555 (getmail-retriever-config
19556 (getmail-retriever-configuration
19557 (type "SimpleIMAPSSLRetriever")
19558 (server "imap.example.com")
19560 (username "patchwork")
19562 (list (file-append coreutils "/bin/cat")
19563 "/etc/getmail-patchwork-imap-password"))
19565 '((mailboxes . ("Patches"))))))))
19569 There are three records for configuring the Patchwork service. The
19570 @code{<patchwork-configuration>} relates to the configuration for Patchwork
19571 within the HTTPD service.
19573 The @code{settings-module} field within the @code{<patchwork-configuration>}
19574 record can be populated with the @code{<patchwork-settings-module>} record,
19575 which describes a settings module that is generated within the Guix store.
19577 For the @code{database-configuration} field within the
19578 @code{<patchwork-settings-module>}, the
19579 @code{<patchwork-database-configuration>} must be used.
19581 @deftp {Data Type} patchwork-configuration
19582 Data type representing the Patchwork service configuration. This type has the
19583 following parameters:
19586 @item @code{patchwork} (default: @code{patchwork})
19587 The Patchwork package to use.
19589 @item @code{domain}
19590 The domain to use for Patchwork, this is used in the HTTPD service virtual
19593 @item @code{settings-module}
19594 The settings module to use for Patchwork. As a Django application, Patchwork
19595 is configured with a Python module containing the settings. This can either be
19596 an instance of the @code{<patchwork-settings-module>} record, any other record
19597 that represents the settings in the store, or a directory outside of the
19600 @item @code{static-path} (default: @code{"/static/"})
19601 The path under which the HTTPD service should serve the static files.
19603 @item @code{getmail-retriever-config}
19604 The getmail-retriever-configuration record value to use with
19605 Patchwork. Getmail will be configured with this value, the messages will be
19606 delivered to Patchwork.
19611 @deftp {Data Type} patchwork-settings-module
19612 Data type representing a settings module for Patchwork. Some of these
19613 settings relate directly to Patchwork, but others relate to Django, the web
19614 framework used by Patchwork, or the Django Rest Framework library. This type
19615 has the following parameters:
19618 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
19619 The database connection settings used for Patchwork. See the
19620 @code{<patchwork-database-configuration>} record type for more information.
19622 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
19623 Patchwork, as a Django web application uses a secret key for cryptographically
19624 signing values. This file should contain a unique unpredictable value.
19626 If this file does not exist, it will be created and populated with a random
19627 value by the patchwork-setup shepherd service.
19629 This setting relates to Django.
19631 @item @code{allowed-hosts}
19632 A list of valid hosts for this Patchwork service. This should at least include
19633 the domain specified in the @code{<patchwork-configuration>} record.
19635 This is a Django setting.
19637 @item @code{default-from-email}
19638 The email address from which Patchwork should send email by default.
19640 This is a Patchwork setting.
19642 @item @code{static-url} (default: @code{#f})
19643 The URL to use when serving static assets. It can be part of a URL, or a full
19644 URL, but must end in a @code{/}.
19646 If the default value is used, the @code{static-path} value from the
19647 @code{<patchwork-configuration>} record will be used.
19649 This is a Django setting.
19651 @item @code{admins} (default: @code{'()})
19652 Email addresses to send the details of errors that occur. Each value should
19653 be a list containing two elements, the name and then the email address.
19655 This is a Django setting.
19657 @item @code{debug?} (default: @code{#f})
19658 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
19659 messages will be shown.
19661 This is a Django setting.
19663 @item @code{enable-rest-api?} (default: @code{#t})
19664 Whether to enable the Patchwork REST API.
19666 This is a Patchwork setting.
19668 @item @code{enable-xmlrpc?} (default: @code{#t})
19669 Whether to enable the XML RPC API.
19671 This is a Patchwork setting.
19673 @item @code{force-https-links?} (default: @code{#t})
19674 Whether to use HTTPS links on Patchwork pages.
19676 This is a Patchwork setting.
19678 @item @code{extra-settings} (default: @code{""})
19679 Extra code to place at the end of the Patchwork settings module.
19684 @deftp {Data Type} patchwork-database-configuration
19685 Data type representing the database configuration for Patchwork.
19688 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
19689 The database engine to use.
19691 @item @code{name} (default: @code{"patchwork"})
19692 The name of the database to use.
19694 @item @code{user} (default: @code{"httpd"})
19695 The user to connect to the database as.
19697 @item @code{password} (default: @code{""})
19698 The password to use when connecting to the database.
19700 @item @code{host} (default: @code{""})
19701 The host to make the database connection to.
19703 @item @code{port} (default: @code{""})
19704 The port on which to connect to the database.
19709 @subsubheading FastCGI
19712 FastCGI is an interface between the front-end and the back-end of a web
19713 service. It is a somewhat legacy facility; new web services should
19714 generally just talk HTTP between the front-end and the back-end.
19715 However there are a number of back-end services such as PHP or the
19716 optimized HTTP Git repository access that use FastCGI, so we have
19717 support for it in Guix.
19719 To use FastCGI, you configure the front-end web server (e.g., nginx) to
19720 dispatch some subset of its requests to the fastcgi backend, which
19721 listens on a local TCP or UNIX socket. There is an intermediary
19722 @code{fcgiwrap} program that sits between the actual backend process and
19723 the web server. The front-end indicates which backend program to run,
19724 passing that information to the @code{fcgiwrap} process.
19726 @defvr {Scheme Variable} fcgiwrap-service-type
19727 A service type for the @code{fcgiwrap} FastCGI proxy.
19730 @deftp {Data Type} fcgiwrap-configuration
19731 Data type representing the configuration of the @code{fcgiwrap} service.
19732 This type has the following parameters:
19734 @item @code{package} (default: @code{fcgiwrap})
19735 The fcgiwrap package to use.
19737 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
19738 The socket on which the @code{fcgiwrap} process should listen, as a
19739 string. Valid @var{socket} values include
19740 @code{unix:@var{/path/to/unix/socket}},
19741 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
19742 @code{tcp6:[@var{ipv6_addr}]:port}.
19744 @item @code{user} (default: @code{fcgiwrap})
19745 @itemx @code{group} (default: @code{fcgiwrap})
19746 The user and group names, as strings, under which to run the
19747 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
19748 the user asks for the specific user or group names @code{fcgiwrap} that
19749 the corresponding user and/or group is present on the system.
19751 It is possible to configure a FastCGI-backed web service to pass HTTP
19752 authentication information from the front-end to the back-end, and to
19753 allow @code{fcgiwrap} to run the back-end process as a corresponding
19754 local user. To enable this capability on the back-end., run
19755 @code{fcgiwrap} as the @code{root} user and group. Note that this
19756 capability also has to be configured on the front-end as well.
19761 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
19762 with some additional features useful for sites of any size.
19764 These features include:
19766 @item Adaptive process spawning
19767 @item Basic statistics (similar to Apache's mod_status)
19768 @item Advanced process management with graceful stop/start
19769 @item Ability to start workers with different uid/gid/chroot/environment
19770 and different php.ini (replaces safe_mode)
19771 @item Stdout & stderr logging
19772 @item Emergency restart in case of accidental opcode cache destruction
19773 @item Accelerated upload support
19774 @item Support for a "slowlog"
19775 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
19776 a special function to finish request & flush all data while continuing to do
19777 something time-consuming (video converting, stats processing, etc.)
19779 ...@: and much more.
19781 @defvr {Scheme Variable} php-fpm-service-type
19782 A Service type for @code{php-fpm}.
19785 @deftp {Data Type} php-fpm-configuration
19786 Data Type for php-fpm service configuration.
19788 @item @code{php} (default: @code{php})
19789 The php package to use.
19790 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
19791 The address on which to accept FastCGI requests. Valid syntaxes are:
19793 @item @code{"ip.add.re.ss:port"}
19794 Listen on a TCP socket to a specific address on a specific port.
19795 @item @code{"port"}
19796 Listen on a TCP socket to all addresses on a specific port.
19797 @item @code{"/path/to/unix/socket"}
19798 Listen on a unix socket.
19801 @item @code{user} (default: @code{php-fpm})
19802 User who will own the php worker processes.
19803 @item @code{group} (default: @code{php-fpm})
19804 Group of the worker processes.
19805 @item @code{socket-user} (default: @code{php-fpm})
19806 User who can speak to the php-fpm socket.
19807 @item @code{socket-group} (default: @code{php-fpm})
19808 Group that can speak to the php-fpm socket.
19809 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
19810 The process id of the php-fpm process is written to this file
19811 once the service has started.
19812 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
19813 Log for the php-fpm master process.
19814 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
19815 Detailed settings for the php-fpm process manager.
19818 @item @code{<php-fpm-dynamic-process-manager-configuration>}
19819 @item @code{<php-fpm-static-process-manager-configuration>}
19820 @item @code{<php-fpm-on-demand-process-manager-configuration>}
19822 @item @code{display-errors} (default @code{#f})
19823 Determines whether php errors and warning should be sent to clients
19824 and displayed in their browsers.
19825 This is useful for local php development, but a security risk for public sites,
19826 as error messages can reveal passwords and personal data.
19827 @item @code{timezone} (default @code{#f})
19828 Specifies @code{php_admin_value[date.timezone]} parameter.
19829 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
19830 This file will log the @code{stderr} outputs of php worker processes.
19831 Can be set to @code{#f} to disable logging.
19832 @item @code{file} (default @code{#f})
19833 An optional override of the whole configuration.
19834 You can use the @code{mixed-text-file} function or an absolute filepath for it.
19838 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
19839 Data Type for the @code{dynamic} php-fpm process manager. With the
19840 @code{dynamic} process manager, spare worker processes are kept around
19841 based on it's configured limits.
19843 @item @code{max-children} (default: @code{5})
19844 Maximum of worker processes.
19845 @item @code{start-servers} (default: @code{2})
19846 How many worker processes should be started on start-up.
19847 @item @code{min-spare-servers} (default: @code{1})
19848 How many spare worker processes should be kept around at minimum.
19849 @item @code{max-spare-servers} (default: @code{3})
19850 How many spare worker processes should be kept around at maximum.
19854 @deftp {Data type} php-fpm-static-process-manager-configuration
19855 Data Type for the @code{static} php-fpm process manager. With the
19856 @code{static} process manager, an unchanging number of worker processes
19859 @item @code{max-children} (default: @code{5})
19860 Maximum of worker processes.
19864 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
19865 Data Type for the @code{on-demand} php-fpm process manager. With the
19866 @code{on-demand} process manager, worker processes are only created as
19869 @item @code{max-children} (default: @code{5})
19870 Maximum of worker processes.
19871 @item @code{process-idle-timeout} (default: @code{10})
19872 The time in seconds after which a process with no requests is killed.
19877 @deffn {Scheme Procedure} nginx-php-fpm-location @
19878 [#:nginx-package nginx] @
19879 [socket (string-append "/var/run/php" @
19880 (version-major (package-version php)) @
19882 A helper function to quickly add php to an @code{nginx-server-configuration}.
19885 A simple services setup for nginx with php can look like this:
19887 (services (cons* (service dhcp-client-service-type)
19888 (service php-fpm-service-type)
19889 (service nginx-service-type
19890 (nginx-server-configuration
19891 (server-name '("example.com"))
19892 (root "/srv/http/")
19894 (list (nginx-php-location)))
19896 (ssl-certificate #f)
19897 (ssl-certificate-key #f)))
19901 @cindex cat-avatar-generator
19902 The cat avatar generator is a simple service to demonstrate the use of php-fpm
19903 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
19904 the hash of a user's email address.
19906 @deffn {Scheme Procedure} cat-avatar-generator-service @
19907 [#:cache-dir "/var/cache/cat-avatar-generator"] @
19908 [#:package cat-avatar-generator] @
19909 [#:configuration (nginx-server-configuration)]
19910 Returns an nginx-server-configuration that inherits @code{configuration}. It
19911 extends the nginx configuration to add a server block that serves @code{package},
19912 a version of cat-avatar-generator. During execution, cat-avatar-generator will
19913 be able to use @code{cache-dir} as its cache directory.
19916 A simple setup for cat-avatar-generator can look like this:
19918 (services (cons* (cat-avatar-generator-service
19920 (nginx-server-configuration
19921 (server-name '("example.com"))))
19926 @subsubheading Hpcguix-web
19928 @cindex hpcguix-web
19929 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
19930 program is a customizable web interface to browse Guix packages,
19931 initially designed for users of high-performance computing (HPC)
19934 @defvr {Scheme Variable} hpcguix-web-service-type
19935 The service type for @code{hpcguix-web}.
19938 @deftp {Data Type} hpcguix-web-configuration
19939 Data type for the hpcguix-web service configuration.
19943 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
19944 configuration. The main items available in this spec are:
19947 @item @code{title-prefix} (default: @code{"hpcguix | "})
19948 The page title prefix.
19950 @item @code{guix-command} (default: @code{"guix"})
19951 The @command{guix} command.
19953 @item @code{package-filter-proc} (default: @code{(const #t)})
19954 A procedure specifying how to filter packages that are displayed.
19956 @item @code{package-page-extension-proc} (default: @code{(const '())})
19957 Extension package for @code{hpcguix-web}.
19959 @item @code{menu} (default: @code{'()})
19960 Additional entry in page @code{menu}.
19962 @item @code{channels} (default: @code{%default-channels})
19963 List of channels from which the package list is built (@pxref{Channels}).
19965 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
19966 The expiration time, in seconds, after which the package list is rebuilt from
19967 the latest instances of the given channels.
19970 See the hpcguix-web repository for a
19971 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
19974 @item @code{package} (default: @code{hpcguix-web})
19975 The hpcguix-web package to use.
19979 A typical hpcguix-web service declaration looks like this:
19982 (service hpcguix-web-service-type
19983 (hpcguix-web-configuration
19985 #~(define site-config
19986 (hpcweb-configuration
19987 (title-prefix "Guix-HPC - ")
19988 (menu '(("/about" "ABOUT"))))))))
19992 The hpcguix-web service periodically updates the package list it publishes by
19993 pulling channels from Git. To that end, it needs to access X.509 certificates
19994 so that it can authenticate Git servers when communicating over HTTPS, and it
19995 assumes that @file{/etc/ssl/certs} contains those certificates.
19997 Thus, make sure to add @code{nss-certs} or another certificate package to the
19998 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
19999 more information on X.509 certificates.
20002 @node Certificate Services
20003 @subsection Certificate Services
20006 @cindex HTTP, HTTPS
20007 @cindex Let's Encrypt
20008 @cindex TLS certificates
20009 The @code{(gnu services certbot)} module provides a service to
20010 automatically obtain a valid TLS certificate from the Let's Encrypt
20011 certificate authority. These certificates can then be used to serve
20012 content securely over HTTPS or other TLS-based protocols, with the
20013 knowledge that the client will be able to verify the server's
20016 @url{https://letsencrypt.org/, Let's Encrypt} provides the
20017 @code{certbot} tool to automate the certification process. This tool
20018 first securely generates a key on the server. It then makes a request
20019 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
20020 checks that the request originates from the host in question by using a
20021 challenge-response protocol, requiring the server to provide its
20022 response over HTTP. If that protocol completes successfully, the CA
20023 signs the key, resulting in a certificate. That certificate is valid
20024 for a limited period of time, and therefore to continue to provide TLS
20025 services, the server needs to periodically ask the CA to renew its
20028 The certbot service automates this process: the initial key
20029 generation, the initial certification request to the Let's Encrypt
20030 service, the web server challenge/response integration, writing the
20031 certificate to disk, the automated periodic renewals, and the deployment
20032 tasks associated with the renewal (e.g.@: reloading services, copying keys
20033 with different permissions).
20035 Certbot is run twice a day, at a random minute within the hour. It
20036 won't do anything until your certificates are due for renewal or
20037 revoked, but running it regularly would give your service a chance of
20038 staying online in case a Let's Encrypt-initiated revocation happened for
20041 By using this service, you agree to the ACME Subscriber Agreement, which
20042 can be found there:
20043 @url{https://acme-v01.api.letsencrypt.org/directory}.
20045 @defvr {Scheme Variable} certbot-service-type
20046 A service type for the @code{certbot} Let's Encrypt client. Its value
20047 must be a @code{certbot-configuration} record as in this example:
20050 (define %nginx-deploy-hook
20052 "nginx-deploy-hook"
20053 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
20054 (kill pid SIGHUP))))
20056 (service certbot-service-type
20057 (certbot-configuration
20058 (email "foo@@example.net")
20061 (certificate-configuration
20062 (domains '("example.net" "www.example.net"))
20063 (deploy-hook %nginx-deploy-hook))
20064 (certificate-configuration
20065 (domains '("bar.example.net")))))))
20068 See below for details about @code{certbot-configuration}.
20071 @deftp {Data Type} certbot-configuration
20072 Data type representing the configuration of the @code{certbot} service.
20073 This type has the following parameters:
20076 @item @code{package} (default: @code{certbot})
20077 The certbot package to use.
20079 @item @code{webroot} (default: @code{/var/www})
20080 The directory from which to serve the Let's Encrypt challenge/response
20083 @item @code{certificates} (default: @code{()})
20084 A list of @code{certificates-configuration}s for which to generate
20085 certificates and request signatures. Each certificate has a @code{name}
20086 and several @code{domains}.
20089 Mandatory email used for registration, recovery contact, and important
20090 account notifications.
20092 @item @code{rsa-key-size} (default: @code{2048})
20093 Size of the RSA key.
20095 @item @code{default-location} (default: @i{see below})
20096 The default @code{nginx-location-configuration}. Because @code{certbot}
20097 needs to be able to serve challenges and responses, it needs to be able
20098 to run a web server. It does so by extending the @code{nginx} web
20099 service with an @code{nginx-server-configuration} listening on the
20100 @var{domains} on port 80, and which has a
20101 @code{nginx-location-configuration} for the @code{/.well-known/} URI
20102 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
20103 these nginx configuration data types.
20105 Requests to other URL paths will be matched by the
20106 @code{default-location}, which if present is added to all
20107 @code{nginx-server-configuration}s.
20109 By default, the @code{default-location} will issue a redirect from
20110 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
20111 you to define what to serve on your site via @code{https}.
20113 Pass @code{#f} to not issue a default location.
20117 @deftp {Data Type} certificate-configuration
20118 Data type representing the configuration of a certificate.
20119 This type has the following parameters:
20122 @item @code{name} (default: @i{see below})
20123 This name is used by Certbot for housekeeping and in file paths; it
20124 doesn't affect the content of the certificate itself. To see
20125 certificate names, run @code{certbot certificates}.
20127 Its default is the first provided domain.
20129 @item @code{domains} (default: @code{()})
20130 The first domain provided will be the subject CN of the certificate, and
20131 all domains will be Subject Alternative Names on the certificate.
20133 @item @code{challenge} (default: @code{#f})
20134 The challenge type that has to be run by certbot. If @code{#f} is specified,
20135 default to the HTTP challenge. If a value is specified, defaults to the
20136 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
20137 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}).
20139 @item @code{authentication-hook} (default: @code{#f})
20140 Command to be run in a shell once for each certificate challenge to be
20141 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
20142 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
20143 contains the validation string and @code{$CERTBOT_TOKEN} contains the
20144 file name of the resource requested when performing an HTTP-01 challenge.
20146 @item @code{cleanup-hook} (default: @code{#f})
20147 Command to be run in a shell once for each certificate challenge that
20148 have been answered by the @code{auth-hook}. For this command, the shell
20149 variables available in the @code{auth-hook} script are still available, and
20150 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
20151 of the @code{auth-hook} script.
20153 @item @code{deploy-hook} (default: @code{#f})
20154 Command to be run in a shell once for each successfully issued
20155 certificate. For this command, the shell variable
20156 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
20157 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
20158 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
20159 contain a space-delimited list of renewed certificate domains (for
20160 example, @samp{"example.com www.example.com"}.
20165 For each @code{certificate-configuration}, the certificate is saved to
20166 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
20167 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
20169 @subsection DNS Services
20170 @cindex DNS (domain name system)
20171 @cindex domain name system (DNS)
20173 The @code{(gnu services dns)} module provides services related to the
20174 @dfn{domain name system} (DNS). It provides a server service for hosting
20175 an @emph{authoritative} DNS server for multiple zones, slave or master.
20176 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
20177 caching and forwarding DNS server for the LAN, which uses
20178 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
20180 @subsubheading Knot Service
20182 An example configuration of an authoritative server for two zones, one master
20186 (define-zone-entries example.org.zone
20187 ;; Name TTL Class Type Data
20188 ("@@" "" "IN" "A" "127.0.0.1")
20189 ("@@" "" "IN" "NS" "ns")
20190 ("ns" "" "IN" "A" "127.0.0.1"))
20192 (define master-zone
20193 (knot-zone-configuration
20194 (domain "example.org")
20196 (origin "example.org")
20197 (entries example.org.zone)))))
20200 (knot-zone-configuration
20201 (domain "plop.org")
20202 (dnssec-policy "default")
20203 (master (list "plop-master"))))
20205 (define plop-master
20206 (knot-remote-configuration
20208 (address (list "208.76.58.171"))))
20212 (services (cons* (service knot-service-type
20213 (knot-configuration
20214 (remotes (list plop-master))
20215 (zones (list master-zone slave-zone))))
20220 @deffn {Scheme Variable} knot-service-type
20221 This is the type for the Knot DNS server.
20223 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
20224 zones, that is to say domain names you would buy from a registrar. This server
20225 is not a resolver, meaning that it can only resolve names for which it is
20226 authoritative. This server can be configured to serve zones as a master server
20227 or a slave server as a per-zone basis. Slave zones will get their data from
20228 masters, and will serve it as an authoritative server. From the point of view
20229 of a resolver, there is no difference between master and slave.
20231 The following data types are used to configure the Knot DNS server:
20234 @deftp {Data Type} knot-key-configuration
20235 Data type representing a key.
20236 This type has the following parameters:
20239 @item @code{id} (default: @code{""})
20240 An identifier for other configuration fields to refer to this key. IDs must
20241 be unique and must not be empty.
20243 @item @code{algorithm} (default: @code{#f})
20244 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
20245 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
20246 and @code{'hmac-sha512}.
20248 @item @code{secret} (default: @code{""})
20249 The secret key itself.
20254 @deftp {Data Type} knot-acl-configuration
20255 Data type representing an Access Control List (ACL) configuration.
20256 This type has the following parameters:
20259 @item @code{id} (default: @code{""})
20260 An identifier for ether configuration fields to refer to this key. IDs must be
20261 unique and must not be empty.
20263 @item @code{address} (default: @code{'()})
20264 An ordered list of IP addresses, network subnets, or network ranges represented
20265 with strings. The query must match one of them. Empty value means that
20266 address match is not required.
20268 @item @code{key} (default: @code{'()})
20269 An ordered list of references to keys represented with strings. The string
20270 must match a key ID defined in a @code{knot-key-configuration}. No key means
20271 that a key is not require to match that ACL.
20273 @item @code{action} (default: @code{'()})
20274 An ordered list of actions that are permitted or forbidden by this ACL. Possible
20275 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
20276 and @code{'update}.
20278 @item @code{deny?} (default: @code{#f})
20279 When true, the ACL defines restrictions. Listed actions are forbidden. When
20280 false, listed actions are allowed.
20285 @deftp {Data Type} zone-entry
20286 Data type represnting a record entry in a zone file.
20287 This type has the following parameters:
20290 @item @code{name} (default: @code{"@@"})
20291 The name of the record. @code{"@@"} refers to the origin of the zone. Names
20292 are relative to the origin of the zone. For example, in the @code{example.org}
20293 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
20294 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
20295 refers to @code{ns.example.org}.
20297 @item @code{ttl} (default: @code{""})
20298 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
20300 @item @code{class} (default: @code{"IN"})
20301 The class of the record. Knot currently supports only @code{"IN"} and
20302 partially @code{"CH"}.
20304 @item @code{type} (default: @code{"A"})
20305 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
20306 address), NS (Name Server) and MX (Mail eXchange). Many other types are
20309 @item @code{data} (default: @code{""})
20310 The data contained in the record. For instance an IP address associated with
20311 an A record, or a domain name associated with an NS record. Remember that
20312 domain names are relative to the origin unless they end with a dot.
20317 @deftp {Data Type} zone-file
20318 Data type representing the content of a zone file.
20319 This type has the following parameters:
20322 @item @code{entries} (default: @code{'()})
20323 The list of entries. The SOA record is taken care of, so you don't need to
20324 put it in the list of entries. This list should probably contain an entry
20325 for your primary authoritative DNS server. Other than using a list of entries
20326 directly, you can use @code{define-zone-entries} to define a object containing
20327 the list of entries more easily, that you can later pass to the @code{entries}
20328 field of the @code{zone-file}.
20330 @item @code{origin} (default: @code{""})
20331 The name of your zone. This parameter cannot be empty.
20333 @item @code{ns} (default: @code{"ns"})
20334 The domain of your primary authoritative DNS server. The name is relative to
20335 the origin, unless it ends with a dot. It is mandatory that this primary
20336 DNS server corresponds to an NS record in the zone and that it is associated
20337 to an IP address in the list of entries.
20339 @item @code{mail} (default: @code{"hostmaster"})
20340 An email address people can contact you at, as the owner of the zone. This
20341 is translated as @code{<mail>@@<origin>}.
20343 @item @code{serial} (default: @code{1})
20344 The serial number of the zone. As this is used to keep track of changes by
20345 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
20346 Always increment it when you make a change in your zone.
20348 @item @code{refresh} (default: @code{(* 2 24 3600)})
20349 The frequency at which slaves will do a zone transfer. This value is a number
20350 of seconds. It can be computed by multiplications or with
20351 @code{(string->duration)}.
20353 @item @code{retry} (default: @code{(* 15 60)})
20354 The period after which a slave will retry to contact its master when it fails
20355 to do so a first time.
20357 @item @code{expiry} (default: @code{(* 14 24 3600)})
20358 Default TTL of records. Existing records are considered correct for at most
20359 this amount of time. After this period, resolvers will invalidate their cache
20360 and check again that it still exists.
20362 @item @code{nx} (default: @code{3600})
20363 Default TTL of inexistant records. This delay is usually short because you want
20364 your new domains to reach everyone quickly.
20369 @deftp {Data Type} knot-remote-configuration
20370 Data type representing a remote configuration.
20371 This type has the following parameters:
20374 @item @code{id} (default: @code{""})
20375 An identifier for other configuration fields to refer to this remote. IDs must
20376 be unique and must not be empty.
20378 @item @code{address} (default: @code{'()})
20379 An ordered list of destination IP addresses. Addresses are tried in sequence.
20380 An optional port can be given with the @@ separator. For instance:
20381 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
20383 @item @code{via} (default: @code{'()})
20384 An ordered list of source IP addresses. An empty list will have Knot choose
20385 an appropriate source IP. An optional port can be given with the @@ separator.
20386 The default is to choose at random.
20388 @item @code{key} (default: @code{#f})
20389 A reference to a key, that is a string containing the identifier of a key
20390 defined in a @code{knot-key-configuration} field.
20395 @deftp {Data Type} knot-keystore-configuration
20396 Data type representing a keystore to hold dnssec keys.
20397 This type has the following parameters:
20400 @item @code{id} (default: @code{""})
20401 The id of the keystore. It must not be empty.
20403 @item @code{backend} (default: @code{'pem})
20404 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
20406 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
20407 The configuration string of the backend. An example for the PKCS#11 is:
20408 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
20409 For the pem backend, the string reprensents a path in the file system.
20414 @deftp {Data Type} knot-policy-configuration
20415 Data type representing a dnssec policy. Knot DNS is able to automatically
20416 sign your zones. It can either generate and manage your keys automatically or
20417 use keys that you generate.
20419 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
20420 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
20421 zone. In order to be trusted, the KSK needs to be present in the parent zone
20422 (usually a top-level domain). If your registrar supports dnssec, you will
20423 have to send them your KSK's hash so they can add a DS record in their zone.
20424 This is not automated and need to be done each time you change your KSK.
20426 The policy also defines the lifetime of keys. Usually, ZSK can be changed
20427 easily and use weaker cryptographic functions (they use lower parameters) in
20428 order to sign records quickly, so they are changed often. The KSK however
20429 requires manual interaction with the registrar, so they are changed less often
20430 and use stronger parameters because they sign only one record.
20432 This type has the following parameters:
20435 @item @code{id} (default: @code{""})
20436 The id of the policy. It must not be empty.
20438 @item @code{keystore} (default: @code{"default"})
20439 A reference to a keystore, that is a string containing the identifier of a
20440 keystore defined in a @code{knot-keystore-configuration} field. The
20441 @code{"default"} identifier means the default keystore (a kasp database that
20442 was setup by this service).
20444 @item @code{manual?} (default: @code{#f})
20445 Whether the key management is manual or automatic.
20447 @item @code{single-type-signing?} (default: @code{#f})
20448 When @code{#t}, use the Single-Type Signing Scheme.
20450 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
20451 An algorithm of signing keys and issued signatures.
20453 @item @code{ksk-size} (default: @code{256})
20454 The length of the KSK. Note that this value is correct for the default
20455 algorithm, but would be unsecure for other algorithms.
20457 @item @code{zsk-size} (default: @code{256})
20458 The length of the ZSK. Note that this value is correct for the default
20459 algorithm, but would be unsecure for other algorithms.
20461 @item @code{dnskey-ttl} (default: @code{'default})
20462 The TTL value for DNSKEY records added into zone apex. The special
20463 @code{'default} value means same as the zone SOA TTL.
20465 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
20466 The period between ZSK publication and the next rollover initiation.
20468 @item @code{propagation-delay} (default: @code{(* 24 3600)})
20469 An extra delay added for each key rollover step. This value should be high
20470 enough to cover propagation of data from the master server to all slaves.
20472 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
20473 A validity period of newly issued signatures.
20475 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
20476 A period how long before a signature expiration the signature will be refreshed.
20478 @item @code{nsec3?} (default: @code{#f})
20479 When @code{#t}, NSEC3 will be used instead of NSEC.
20481 @item @code{nsec3-iterations} (default: @code{5})
20482 The number of additional times the hashing is performed.
20484 @item @code{nsec3-salt-length} (default: @code{8})
20485 The length of a salt field in octets, which is appended to the original owner
20486 name before hashing.
20488 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
20489 The validity period of newly issued salt field.
20494 @deftp {Data Type} knot-zone-configuration
20495 Data type representing a zone served by Knot.
20496 This type has the following parameters:
20499 @item @code{domain} (default: @code{""})
20500 The domain served by this configuration. It must not be empty.
20502 @item @code{file} (default: @code{""})
20503 The file where this zone is saved. This parameter is ignored by master zones.
20504 Empty means default location that depends on the domain name.
20506 @item @code{zone} (default: @code{(zone-file)})
20507 The content of the zone file. This parameter is ignored by slave zones. It
20508 must contain a zone-file record.
20510 @item @code{master} (default: @code{'()})
20511 A list of master remotes. When empty, this zone is a master. When set, this
20512 zone is a slave. This is a list of remotes identifiers.
20514 @item @code{ddns-master} (default: @code{#f})
20515 The main master. When empty, it defaults to the first master in the list of
20518 @item @code{notify} (default: @code{'()})
20519 A list of slave remote identifiers.
20521 @item @code{acl} (default: @code{'()})
20522 A list of acl identifiers.
20524 @item @code{semantic-checks?} (default: @code{#f})
20525 When set, this adds more semantic checks to the zone.
20527 @item @code{disable-any?} (default: @code{#f})
20528 When set, this forbids queries of the ANY type.
20530 @item @code{zonefile-sync} (default: @code{0})
20531 The delay between a modification in memory and on disk. 0 means immediate
20534 @item @code{zonefile-load} (default: @code{#f})
20535 The way the zone file contents are applied during zone load. Possible values
20539 @item @code{#f} for using the default value from Knot,
20540 @item @code{'none} for not using the zone file at all,
20541 @item @code{'difference} for computing the difference between already available
20542 contents and zone contents and applying it to the current zone contents,
20543 @item @code{'difference-no-serial} for the same as @code{'difference}, but
20544 ignoring the SOA serial in the zone file, while the server takes care of it
20546 @item @code{'whole} for loading zone contents from the zone file.
20549 @item @code{journal-content} (default: @code{#f})
20550 The way the journal is used to store zone and its changes. Possible values
20551 are @code{'none} to not use it at all, @code{'changes} to store changes and
20552 @code{'all} to store contents. @code{#f} does not set this option, so the
20553 default value from Knot is used.
20555 @item @code{max-journal-usage} (default: @code{#f})
20556 The maximum size for the journal on disk. @code{#f} does not set this option,
20557 so the default value from Knot is used.
20559 @item @code{max-journal-depth} (default: @code{#f})
20560 The maximum size of the history. @code{#f} does not set this option, so the
20561 default value from Knot is used.
20563 @item @code{max-zone-size} (default: @code{#f})
20564 The maximum size of the zone file. This limit is enforced for incoming
20565 transfer and updates. @code{#f} does not set this option, so the default
20566 value from Knot is used.
20568 @item @code{dnssec-policy} (default: @code{#f})
20569 A reference to a @code{knot-policy-configuration} record, or the special
20570 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
20573 @item @code{serial-policy} (default: @code{'increment})
20574 A policy between @code{'increment} and @code{'unixtime}.
20579 @deftp {Data Type} knot-configuration
20580 Data type representing the Knot configuration.
20581 This type has the following parameters:
20584 @item @code{knot} (default: @code{knot})
20587 @item @code{run-directory} (default: @code{"/var/run/knot"})
20588 The run directory. This directory will be used for pid file and sockets.
20590 @item @code{includes} (default: @code{'()})
20591 A list of strings or file-like objects denoting other files that must be
20592 included at the top of the configuration file.
20594 @cindex secrets, Knot service
20595 This can be used to manage secrets out-of-band. For example, secret
20596 keys may be stored in an out-of-band file not managed by Guix, and
20597 thus not visible in @file{/gnu/store}---e.g., you could store secret
20598 key configuration in @file{/etc/knot/secrets.conf} and add this file
20599 to the @code{includes} list.
20601 It can also be used to add configuration not supported by this interface.
20603 @item @code{listen-v4} (default: @code{"0.0.0.0"})
20604 An ip address on which to listen.
20606 @item @code{listen-v6} (default: @code{"::"})
20607 An ip address on which to listen.
20609 @item @code{listen-port} (default: @code{53})
20610 A port on which to listen.
20612 @item @code{keys} (default: @code{'()})
20613 The list of knot-key-configuration used by this configuration.
20615 @item @code{acls} (default: @code{'()})
20616 The list of knot-acl-configuration used by this configuration.
20618 @item @code{remotes} (default: @code{'()})
20619 The list of knot-remote-configuration used by this configuration.
20621 @item @code{zones} (default: @code{'()})
20622 The list of knot-zone-configuration used by this configuration.
20627 @subsubheading Dnsmasq Service
20629 @deffn {Scheme Variable} dnsmasq-service-type
20630 This is the type of the dnsmasq service, whose value should be an
20631 @code{dnsmasq-configuration} object as in this example:
20634 (service dnsmasq-service-type
20635 (dnsmasq-configuration
20637 (servers '("192.168.1.1"))))
20641 @deftp {Data Type} dnsmasq-configuration
20642 Data type representing the configuration of dnsmasq.
20645 @item @code{package} (default: @var{dnsmasq})
20646 Package object of the dnsmasq server.
20648 @item @code{no-hosts?} (default: @code{#f})
20649 When true, don't read the hostnames in /etc/hosts.
20651 @item @code{port} (default: @code{53})
20652 The port to listen on. Setting this to zero completely disables DNS
20653 responses, leaving only DHCP and/or TFTP functions.
20655 @item @code{local-service?} (default: @code{#t})
20656 Accept DNS queries only from hosts whose address is on a local subnet,
20657 ie a subnet for which an interface exists on the server.
20659 @item @code{listen-addresses} (default: @code{'()})
20660 Listen on the given IP addresses.
20662 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
20663 The file to read the IP address of the upstream nameservers from.
20665 @item @code{no-resolv?} (default: @code{#f})
20666 When true, don't read @var{resolv-file}.
20668 @item @code{servers} (default: @code{'()})
20669 Specify IP address of upstream servers directly.
20671 @item @code{cache-size} (default: @code{150})
20672 Set the size of dnsmasq's cache. Setting the cache size to zero
20675 @item @code{negative-cache?} (default: @code{#t})
20676 When false, disable negative caching.
20681 @subsubheading ddclient Service
20684 The ddclient service described below runs the ddclient daemon, which takes
20685 care of automatically updating DNS entries for service providers such as
20686 @uref{https://dyn.com/dns/, Dyn}.
20688 The following example show instantiates the service with its default
20692 (service ddclient-service-type)
20695 Note that ddclient needs to access credentials that are stored in a
20696 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
20697 @code{secret-file} below.) You are expected to create this file manually, in
20698 an ``out-of-band'' fashion (you @emph{could} make this file part of the
20699 service configuration, for instance by using @code{plain-file}, but it will be
20700 world-readable @i{via} @file{/gnu/store}.) See the examples in the
20701 @file{share/ddclient} directory of the @code{ddclient} package.
20703 @c %start of fragment
20705 Available @code{ddclient-configuration} fields are:
20707 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
20708 The ddclient package.
20712 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
20713 The period after which ddclient will retry to check IP and domain name.
20715 Defaults to @samp{300}.
20719 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
20720 Use syslog for the output.
20722 Defaults to @samp{#t}.
20726 @deftypevr {@code{ddclient-configuration} parameter} string mail
20729 Defaults to @samp{"root"}.
20733 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
20734 Mail failed update to user.
20736 Defaults to @samp{"root"}.
20740 @deftypevr {@code{ddclient-configuration} parameter} string pid
20741 The ddclient PID file.
20743 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
20747 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
20748 Enable SSL support.
20750 Defaults to @samp{#t}.
20754 @deftypevr {@code{ddclient-configuration} parameter} string user
20755 Specifies the user name or ID that is used when running ddclient
20758 Defaults to @samp{"ddclient"}.
20762 @deftypevr {@code{ddclient-configuration} parameter} string group
20763 Group of the user who will run the ddclient program.
20765 Defaults to @samp{"ddclient"}.
20769 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
20770 Secret file which will be appended to @file{ddclient.conf} file. This
20771 file contains credentials for use by ddclient. You are expected to
20772 create it manually.
20774 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
20778 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
20779 Extra options will be appended to @file{ddclient.conf} file.
20781 Defaults to @samp{()}.
20786 @c %end of fragment
20790 @subsection VPN Services
20791 @cindex VPN (virtual private network)
20792 @cindex virtual private network (VPN)
20794 The @code{(gnu services vpn)} module provides services related to
20795 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
20796 your machine to connect to a VPN, and a @emph{server} service for your machine
20797 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
20799 @deffn {Scheme Procedure} openvpn-client-service @
20800 [#:config (openvpn-client-configuration)]
20802 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
20805 @deffn {Scheme Procedure} openvpn-server-service @
20806 [#:config (openvpn-server-configuration)]
20808 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
20810 Both can be run simultaneously.
20813 @c %automatically generated documentation
20815 Available @code{openvpn-client-configuration} fields are:
20817 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
20818 The OpenVPN package.
20822 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
20823 The OpenVPN pid file.
20825 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
20829 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
20830 The protocol (UDP or TCP) used to open a channel between clients and
20833 Defaults to @samp{udp}.
20837 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
20838 The device type used to represent the VPN connection.
20840 Defaults to @samp{tun}.
20844 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
20845 The certificate authority to check connections against.
20847 Defaults to @samp{"/etc/openvpn/ca.crt"}.
20851 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
20852 The certificate of the machine the daemon is running on. It should be
20853 signed by the authority given in @code{ca}.
20855 Defaults to @samp{"/etc/openvpn/client.crt"}.
20859 @deftypevr {@code{openvpn-client-configuration} parameter} string key
20860 The key of the machine the daemon is running on. It must be the key whose
20861 certificate is @code{cert}.
20863 Defaults to @samp{"/etc/openvpn/client.key"}.
20867 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
20868 Whether to use the lzo compression algorithm.
20870 Defaults to @samp{#t}.
20874 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
20875 Don't re-read key files across SIGUSR1 or --ping-restart.
20877 Defaults to @samp{#t}.
20881 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
20882 Don't close and reopen TUN/TAP device or run up/down scripts across
20883 SIGUSR1 or --ping-restart restarts.
20885 Defaults to @samp{#t}.
20889 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
20892 Defaults to @samp{3}.
20896 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
20897 Add an additional layer of HMAC authentication on top of the TLS control
20898 channel to protect against DoS attacks.
20900 Defaults to @samp{#f}.
20904 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
20905 Whether to check the server certificate has server usage extension.
20907 Defaults to @samp{#t}.
20911 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
20912 Bind to a specific local port number.
20914 Defaults to @samp{#f}.
20918 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
20919 Retry resolving server address.
20921 Defaults to @samp{#t}.
20925 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
20926 A list of remote servers to connect to.
20928 Defaults to @samp{()}.
20930 Available @code{openvpn-remote-configuration} fields are:
20932 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
20935 Defaults to @samp{"my-server"}.
20939 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
20940 Port number the server listens to.
20942 Defaults to @samp{1194}.
20947 @c %end of automatic openvpn-client documentation
20949 @c %automatically generated documentation
20951 Available @code{openvpn-server-configuration} fields are:
20953 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
20954 The OpenVPN package.
20958 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
20959 The OpenVPN pid file.
20961 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
20965 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
20966 The protocol (UDP or TCP) used to open a channel between clients and
20969 Defaults to @samp{udp}.
20973 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
20974 The device type used to represent the VPN connection.
20976 Defaults to @samp{tun}.
20980 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
20981 The certificate authority to check connections against.
20983 Defaults to @samp{"/etc/openvpn/ca.crt"}.
20987 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
20988 The certificate of the machine the daemon is running on. It should be
20989 signed by the authority given in @code{ca}.
20991 Defaults to @samp{"/etc/openvpn/client.crt"}.
20995 @deftypevr {@code{openvpn-server-configuration} parameter} string key
20996 The key of the machine the daemon is running on. It must be the key whose
20997 certificate is @code{cert}.
20999 Defaults to @samp{"/etc/openvpn/client.key"}.
21003 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
21004 Whether to use the lzo compression algorithm.
21006 Defaults to @samp{#t}.
21010 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
21011 Don't re-read key files across SIGUSR1 or --ping-restart.
21013 Defaults to @samp{#t}.
21017 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
21018 Don't close and reopen TUN/TAP device or run up/down scripts across
21019 SIGUSR1 or --ping-restart restarts.
21021 Defaults to @samp{#t}.
21025 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
21028 Defaults to @samp{3}.
21032 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
21033 Add an additional layer of HMAC authentication on top of the TLS control
21034 channel to protect against DoS attacks.
21036 Defaults to @samp{#f}.
21040 @deftypevr {@code{openvpn-server-configuration} parameter} number port
21041 Specifies the port number on which the server listens.
21043 Defaults to @samp{1194}.
21047 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
21048 An ip and mask specifying the subnet inside the virtual network.
21050 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
21054 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
21055 A CIDR notation specifying the IPv6 subnet inside the virtual network.
21057 Defaults to @samp{#f}.
21061 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
21062 The Diffie-Hellman parameters file.
21064 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
21068 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
21069 The file that records client IPs.
21071 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
21075 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
21076 When true, the server will act as a gateway for its clients.
21078 Defaults to @samp{#f}.
21082 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
21083 When true, clients are allowed to talk to each other inside the VPN.
21085 Defaults to @samp{#f}.
21089 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
21090 Causes ping-like messages to be sent back and forth over the link so
21091 that each side knows when the other side has gone down. @code{keepalive}
21092 requires a pair. The first element is the period of the ping sending,
21093 and the second element is the timeout before considering the other side
21098 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
21099 The maximum number of clients.
21101 Defaults to @samp{100}.
21105 @deftypevr {@code{openvpn-server-configuration} parameter} string status
21106 The status file. This file shows a small report on current connection.
21107 It is truncated and rewritten every minute.
21109 Defaults to @samp{"/var/run/openvpn/status"}.
21113 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
21114 The list of configuration for some clients.
21116 Defaults to @samp{()}.
21118 Available @code{openvpn-ccd-configuration} fields are:
21120 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
21123 Defaults to @samp{"client"}.
21127 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
21130 Defaults to @samp{#f}.
21134 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
21137 Defaults to @samp{#f}.
21144 @c %end of automatic openvpn-server documentation
21147 @node Network File System
21148 @subsection Network File System
21151 The @code{(gnu services nfs)} module provides the following services,
21152 which are most commonly used in relation to mounting or exporting
21153 directory trees as @dfn{network file systems} (NFS).
21155 @subsubheading RPC Bind Service
21158 The RPC Bind service provides a facility to map program numbers into
21159 universal addresses.
21160 Many NFS related services use this facility. Hence it is automatically
21161 started when a dependent service starts.
21163 @defvr {Scheme Variable} rpcbind-service-type
21164 A service type for the RPC portmapper daemon.
21168 @deftp {Data Type} rpcbind-configuration
21169 Data type representing the configuration of the RPC Bind Service.
21170 This type has the following parameters:
21172 @item @code{rpcbind} (default: @code{rpcbind})
21173 The rpcbind package to use.
21175 @item @code{warm-start?} (default: @code{#t})
21176 If this parameter is @code{#t}, then the daemon will read a
21177 state file on startup thus reloading state information saved by a previous
21183 @subsubheading Pipefs Pseudo File System
21187 The pipefs file system is used to transfer NFS related data
21188 between the kernel and user space programs.
21190 @defvr {Scheme Variable} pipefs-service-type
21191 A service type for the pipefs pseudo file system.
21194 @deftp {Data Type} pipefs-configuration
21195 Data type representing the configuration of the pipefs pseudo file system service.
21196 This type has the following parameters:
21198 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21199 The directory to which the file system is to be attached.
21204 @subsubheading GSS Daemon Service
21207 @cindex global security system
21209 The @dfn{global security system} (GSS) daemon provides strong security for RPC
21211 Before exchanging RPC requests an RPC client must establish a security
21212 context. Typically this is done using the Kerberos command @command{kinit}
21213 or automatically at login time using PAM services (@pxref{Kerberos Services}).
21215 @defvr {Scheme Variable} gss-service-type
21216 A service type for the Global Security System (GSS) daemon.
21219 @deftp {Data Type} gss-configuration
21220 Data type representing the configuration of the GSS daemon service.
21221 This type has the following parameters:
21223 @item @code{nfs-utils} (default: @code{nfs-utils})
21224 The package in which the @command{rpc.gssd} command is to be found.
21226 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21227 The directory where the pipefs file system is mounted.
21233 @subsubheading IDMAP Daemon Service
21235 @cindex name mapper
21237 The idmap daemon service provides mapping between user IDs and user names.
21238 Typically it is required in order to access file systems mounted via NFSv4.
21240 @defvr {Scheme Variable} idmap-service-type
21241 A service type for the Identity Mapper (IDMAP) daemon.
21244 @deftp {Data Type} idmap-configuration
21245 Data type representing the configuration of the IDMAP daemon service.
21246 This type has the following parameters:
21248 @item @code{nfs-utils} (default: @code{nfs-utils})
21249 The package in which the @command{rpc.idmapd} command is to be found.
21251 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21252 The directory where the pipefs file system is mounted.
21254 @item @code{domain} (default: @code{#f})
21255 The local NFSv4 domain name.
21256 This must be a string or @code{#f}.
21257 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
21262 @node Continuous Integration
21263 @subsection Continuous Integration
21265 @cindex continuous integration
21266 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
21267 continuous integration tool for Guix. It can be used both for development and
21268 for providing substitutes to others (@pxref{Substitutes}).
21270 The @code{(gnu services cuirass)} module provides the following service.
21272 @defvr {Scheme Procedure} cuirass-service-type
21273 The type of the Cuirass service. Its value must be a
21274 @code{cuirass-configuration} object, as described below.
21277 To add build jobs, you have to set the @code{specifications} field of the
21278 configuration. Here is an example of a service that polls the Guix repository
21279 and builds the packages from a manifest. Some of the packages are defined in
21280 the @code{"custom-packages"} input, which is the equivalent of
21281 @code{GUIX_PACKAGE_PATH}.
21284 (define %cuirass-specs
21286 '((#:name . "my-manifest")
21287 (#:load-path-inputs . ("guix"))
21288 (#:package-path-inputs . ("custom-packages"))
21289 (#:proc-input . "guix")
21290 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
21291 (#:proc . cuirass-jobs)
21292 (#:proc-args . ((subset . "manifests")
21293 (systems . ("x86_64-linux"))
21294 (manifests . (("config" . "guix/manifest.scm")))))
21295 (#:inputs . (((#:name . "guix")
21296 (#:url . "git://git.savannah.gnu.org/guix.git")
21297 (#:load-path . ".")
21298 (#:branch . "master")
21299 (#:no-compile? . #t))
21300 ((#:name . "config")
21301 (#:url . "git://git.example.org/config.git")
21302 (#:load-path . ".")
21303 (#:branch . "master")
21304 (#:no-compile? . #t))
21305 ((#:name . "custom-packages")
21306 (#:url . "git://git.example.org/custom-packages.git")
21307 (#:load-path . ".")
21308 (#:branch . "master")
21309 (#:no-compile? . #t)))))))
21311 (service cuirass-service-type
21312 (cuirass-configuration
21313 (specifications %cuirass-specs)))
21316 While information related to build jobs is located directly in the
21317 specifications, global settings for the @command{cuirass} process are
21318 accessible in other @code{cuirass-configuration} fields.
21320 @deftp {Data Type} cuirass-configuration
21321 Data type representing the configuration of Cuirass.
21324 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
21325 Location of the log file.
21327 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
21328 Location of the repository cache.
21330 @item @code{user} (default: @code{"cuirass"})
21331 Owner of the @code{cuirass} process.
21333 @item @code{group} (default: @code{"cuirass"})
21334 Owner's group of the @code{cuirass} process.
21336 @item @code{interval} (default: @code{60})
21337 Number of seconds between the poll of the repositories followed by the
21340 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
21341 Location of sqlite database which contains the build results and previously
21342 added specifications.
21344 @item @code{ttl} (default: @code{(* 30 24 3600)})
21345 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
21346 are registered for build results. This means that build results are protected
21347 from garbage collection for at least @var{ttl} seconds.
21349 @item @code{port} (default: @code{8081})
21350 Port number used by the HTTP server.
21352 @item --listen=@var{host}
21353 Listen on the network interface for @var{host}. The default is to
21354 accept connections from localhost.
21356 @item @code{specifications} (default: @code{#~'()})
21357 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
21358 where a specification is an association list
21359 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
21360 keys are keywords (@code{#:keyword-example}) as shown in the example
21363 @item @code{use-substitutes?} (default: @code{#f})
21364 This allows using substitutes to avoid building every dependencies of a job
21367 @item @code{one-shot?} (default: @code{#f})
21368 Only evaluate specifications and build derivations once.
21370 @item @code{fallback?} (default: @code{#f})
21371 When substituting a pre-built binary fails, fall back to building
21374 @item @code{cuirass} (default: @code{cuirass})
21375 The Cuirass package to use.
21379 @node Power Management Services
21380 @subsection Power Management Services
21383 @cindex power management with TLP
21384 @subsubheading TLP daemon
21386 The @code{(gnu services pm)} module provides a Guix service definition
21387 for the Linux power management tool TLP.
21389 TLP enables various powersaving modes in userspace and kernel.
21390 Contrary to @code{upower-service}, it is not a passive,
21391 monitoring tool, as it will apply custom settings each time a new power
21392 source is detected. More information can be found at
21393 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
21395 @deffn {Scheme Variable} tlp-service-type
21396 The service type for the TLP tool. Its value should be a valid
21397 TLP configuration (see below). To use the default settings, simply
21400 (service tlp-service-type)
21404 By default TLP does not need much configuration but most TLP parameters
21405 can be tweaked using @code{tlp-configuration}.
21407 Each parameter definition is preceded by its type; for example,
21408 @samp{boolean foo} indicates that the @code{foo} parameter
21409 should be specified as a boolean. Types starting with
21410 @code{maybe-} denote parameters that won't show up in TLP config file
21411 when their value is @code{'disabled}.
21413 @c The following documentation was initially generated by
21414 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
21415 @c documentation is better, so we shouldn't hesitate to edit below as
21416 @c needed. However if the change you want to make to this documentation
21417 @c can be done in an automated way, it's probably easier to change
21418 @c (generate-documentation) than to make it below and have to deal with
21419 @c the churn as TLP updates.
21421 Available @code{tlp-configuration} fields are:
21423 @deftypevr {@code{tlp-configuration} parameter} package tlp
21428 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
21429 Set to true if you wish to enable TLP.
21431 Defaults to @samp{#t}.
21435 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
21436 Default mode when no power supply can be detected. Alternatives are AC
21439 Defaults to @samp{"AC"}.
21443 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
21444 Number of seconds Linux kernel has to wait after the disk goes idle,
21445 before syncing on AC.
21447 Defaults to @samp{0}.
21451 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
21452 Same as @code{disk-idle-ac} but on BAT mode.
21454 Defaults to @samp{2}.
21458 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
21459 Dirty pages flushing periodicity, expressed in seconds.
21461 Defaults to @samp{15}.
21465 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
21466 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
21468 Defaults to @samp{60}.
21472 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
21473 CPU frequency scaling governor on AC mode. With intel_pstate driver,
21474 alternatives are powersave and performance. With acpi-cpufreq driver,
21475 alternatives are ondemand, powersave, performance and conservative.
21477 Defaults to @samp{disabled}.
21481 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
21482 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
21484 Defaults to @samp{disabled}.
21488 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
21489 Set the min available frequency for the scaling governor on AC.
21491 Defaults to @samp{disabled}.
21495 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
21496 Set the max available frequency for the scaling governor on AC.
21498 Defaults to @samp{disabled}.
21502 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
21503 Set the min available frequency for the scaling governor on BAT.
21505 Defaults to @samp{disabled}.
21509 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
21510 Set the max available frequency for the scaling governor on BAT.
21512 Defaults to @samp{disabled}.
21516 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
21517 Limit the min P-state to control the power dissipation of the CPU, in AC
21518 mode. Values are stated as a percentage of the available performance.
21520 Defaults to @samp{disabled}.
21524 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
21525 Limit the max P-state to control the power dissipation of the CPU, in AC
21526 mode. Values are stated as a percentage of the available performance.
21528 Defaults to @samp{disabled}.
21532 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
21533 Same as @code{cpu-min-perf-on-ac} on BAT mode.
21535 Defaults to @samp{disabled}.
21539 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
21540 Same as @code{cpu-max-perf-on-ac} on BAT mode.
21542 Defaults to @samp{disabled}.
21546 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
21547 Enable CPU turbo boost feature on AC mode.
21549 Defaults to @samp{disabled}.
21553 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
21554 Same as @code{cpu-boost-on-ac?} on BAT mode.
21556 Defaults to @samp{disabled}.
21560 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
21561 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
21562 used under light load conditions.
21564 Defaults to @samp{#f}.
21568 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
21569 Same as @code{sched-powersave-on-ac?} but on BAT mode.
21571 Defaults to @samp{#t}.
21575 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
21576 Enable Linux kernel NMI watchdog.
21578 Defaults to @samp{#f}.
21582 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
21583 For Linux kernels with PHC patch applied, change CPU voltages. An
21584 example value would be @samp{"F:V F:V F:V F:V"}.
21586 Defaults to @samp{disabled}.
21590 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
21591 Set CPU performance versus energy saving policy on AC. Alternatives are
21592 performance, normal, powersave.
21594 Defaults to @samp{"performance"}.
21598 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
21599 Same as @code{energy-perf-policy-ac} but on BAT mode.
21601 Defaults to @samp{"powersave"}.
21605 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
21610 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
21611 Hard disk advanced power management level.
21615 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
21616 Same as @code{disk-apm-bat} but on BAT mode.
21620 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
21621 Hard disk spin down timeout. One value has to be specified for each
21622 declared hard disk.
21624 Defaults to @samp{disabled}.
21628 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
21629 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
21631 Defaults to @samp{disabled}.
21635 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
21636 Select IO scheduler for disk devices. One value has to be specified for
21637 each declared hard disk. Example alternatives are cfq, deadline and
21640 Defaults to @samp{disabled}.
21644 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
21645 SATA aggressive link power management (ALPM) level. Alternatives are
21646 min_power, medium_power, max_performance.
21648 Defaults to @samp{"max_performance"}.
21652 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
21653 Same as @code{sata-linkpwr-ac} but on BAT mode.
21655 Defaults to @samp{"min_power"}.
21659 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
21660 Exclude specified SATA host devices for link power management.
21662 Defaults to @samp{disabled}.
21666 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
21667 Enable Runtime Power Management for AHCI controller and disks on AC
21670 Defaults to @samp{disabled}.
21674 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
21675 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
21677 Defaults to @samp{disabled}.
21681 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
21682 Seconds of inactivity before disk is suspended.
21684 Defaults to @samp{15}.
21688 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
21689 PCI Express Active State Power Management level. Alternatives are
21690 default, performance, powersave.
21692 Defaults to @samp{"performance"}.
21696 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
21697 Same as @code{pcie-aspm-ac} but on BAT mode.
21699 Defaults to @samp{"powersave"}.
21703 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
21704 Radeon graphics clock speed level. Alternatives are low, mid, high,
21707 Defaults to @samp{"high"}.
21711 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
21712 Same as @code{radeon-power-ac} but on BAT mode.
21714 Defaults to @samp{"low"}.
21718 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
21719 Radeon dynamic power management method (DPM). Alternatives are battery,
21722 Defaults to @samp{"performance"}.
21726 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
21727 Same as @code{radeon-dpm-state-ac} but on BAT mode.
21729 Defaults to @samp{"battery"}.
21733 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
21734 Radeon DPM performance level. Alternatives are auto, low, high.
21736 Defaults to @samp{"auto"}.
21740 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
21741 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
21743 Defaults to @samp{"auto"}.
21747 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
21748 Wifi power saving mode.
21750 Defaults to @samp{#f}.
21754 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
21755 Same as @code{wifi-power-ac?} but on BAT mode.
21757 Defaults to @samp{#t}.
21761 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
21762 Disable wake on LAN.
21764 Defaults to @samp{#t}.
21768 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
21769 Timeout duration in seconds before activating audio power saving on
21770 Intel HDA and AC97 devices. A value of 0 disables power saving.
21772 Defaults to @samp{0}.
21776 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
21777 Same as @code{sound-powersave-ac} but on BAT mode.
21779 Defaults to @samp{1}.
21783 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
21784 Disable controller in powersaving mode on Intel HDA devices.
21786 Defaults to @samp{#t}.
21790 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
21791 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
21792 powered on again by releasing (and reinserting) the eject lever or by
21793 pressing the disc eject button on newer models.
21795 Defaults to @samp{#f}.
21799 @deftypevr {@code{tlp-configuration} parameter} string bay-device
21800 Name of the optical drive device to power off.
21802 Defaults to @samp{"sr0"}.
21806 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
21807 Runtime Power Management for PCI(e) bus devices. Alternatives are on
21810 Defaults to @samp{"on"}.
21814 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
21815 Same as @code{runtime-pm-ac} but on BAT mode.
21817 Defaults to @samp{"auto"}.
21821 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
21822 Runtime Power Management for all PCI(e) bus devices, except blacklisted
21825 Defaults to @samp{#t}.
21829 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
21830 Exclude specified PCI(e) device addresses from Runtime Power Management.
21832 Defaults to @samp{disabled}.
21836 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
21837 Exclude PCI(e) devices assigned to the specified drivers from Runtime
21842 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
21843 Enable USB autosuspend feature.
21845 Defaults to @samp{#t}.
21849 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
21850 Exclude specified devices from USB autosuspend.
21852 Defaults to @samp{disabled}.
21856 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
21857 Exclude WWAN devices from USB autosuspend.
21859 Defaults to @samp{#t}.
21863 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
21864 Include specified devices into USB autosuspend, even if they are already
21865 excluded by the driver or via @code{usb-blacklist-wwan?}.
21867 Defaults to @samp{disabled}.
21871 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
21872 Enable USB autosuspend before shutdown.
21874 Defaults to @samp{disabled}.
21878 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
21879 Restore radio device state (bluetooth, wifi, wwan) from previous
21880 shutdown on system startup.
21882 Defaults to @samp{#f}.
21887 @cindex CPU frequency scaling with thermald
21888 @subsubheading Thermald daemon
21890 The @code{(gnu services pm)} module provides an interface to
21891 thermald, a CPU frequency scaling service which helps prevent overheating.
21893 @defvr {Scheme Variable} thermald-service-type
21894 This is the service type for
21895 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
21896 Thermal Daemon, which is responsible for controlling the thermal state
21897 of processors and preventing overheating.
21900 @deftp {Data Type} thermald-configuration
21901 Data type representing the configuration of @code{thermald-service-type}.
21904 @item @code{ignore-cpuid-check?} (default: @code{#f})
21905 Ignore cpuid check for supported CPU models.
21907 @item @code{thermald} (default: @var{thermald})
21908 Package object of thermald.
21913 @node Audio Services
21914 @subsection Audio Services
21916 The @code{(gnu services audio)} module provides a service to start MPD
21917 (the Music Player Daemon).
21920 @subsubheading Music Player Daemon
21922 The Music Player Daemon (MPD) is a service that can play music while
21923 being controlled from the local machine or over the network by a variety
21926 The following example shows how one might run @code{mpd} as user
21927 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
21930 (service mpd-service-type
21936 @defvr {Scheme Variable} mpd-service-type
21937 The service type for @command{mpd}
21940 @deftp {Data Type} mpd-configuration
21941 Data type representing the configuration of @command{mpd}.
21944 @item @code{user} (default: @code{"mpd"})
21945 The user to run mpd as.
21947 @item @code{music-dir} (default: @code{"~/Music"})
21948 The directory to scan for music files.
21950 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
21951 The directory to store playlists.
21953 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
21954 The location of the music database.
21956 @item @code{state-file} (default: @code{"~/.mpd/state"})
21957 The location of the file that stores current MPD's state.
21959 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
21960 The location of the sticker database.
21962 @item @code{port} (default: @code{"6600"})
21963 The port to run mpd on.
21965 @item @code{address} (default: @code{"any"})
21966 The address that mpd will bind to. To use a Unix domain socket,
21967 an absolute path can be specified here.
21972 @node Virtualization Services
21973 @subsection Virtualization services
21975 The @code{(gnu services virtualization)} module provides services for
21976 the libvirt and virtlog daemons, as well as other virtualization-related
21979 @subsubheading Libvirt daemon
21980 @code{libvirtd} is the server side daemon component of the libvirt
21981 virtualization management system. This daemon runs on host servers
21982 and performs required management tasks for virtualized guests.
21984 @deffn {Scheme Variable} libvirt-service-type
21985 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
21986 Its value must be a @code{libvirt-configuration}.
21989 (service libvirt-service-type
21990 (libvirt-configuration
21991 (unix-sock-group "libvirt")
21992 (tls-port "16555")))
21996 @c Auto-generated with (generate-libvirt-documentation)
21997 Available @code{libvirt-configuration} fields are:
21999 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
22004 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
22005 Flag listening for secure TLS connections on the public TCP/IP port.
22006 must set @code{listen} for this to have any effect.
22008 It is necessary to setup a CA and issue server certificates before using
22011 Defaults to @samp{#t}.
22015 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
22016 Listen for unencrypted TCP connections on the public TCP/IP port. must
22017 set @code{listen} for this to have any effect.
22019 Using the TCP socket requires SASL authentication by default. Only SASL
22020 mechanisms which support data encryption are allowed. This is
22021 DIGEST_MD5 and GSSAPI (Kerberos5)
22023 Defaults to @samp{#f}.
22027 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
22028 Port for accepting secure TLS connections This can be a port number, or
22031 Defaults to @samp{"16514"}.
22035 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
22036 Port for accepting insecure TCP connections This can be a port number,
22039 Defaults to @samp{"16509"}.
22043 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
22044 IP address or hostname used for client connections.
22046 Defaults to @samp{"0.0.0.0"}.
22050 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
22051 Flag toggling mDNS advertisement of the libvirt service.
22053 Alternatively can disable for all services on a host by stopping the
22056 Defaults to @samp{#f}.
22060 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
22061 Default mDNS advertisement name. This must be unique on the immediate
22064 Defaults to @samp{"Virtualization Host <hostname>"}.
22068 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
22069 UNIX domain socket group ownership. This can be used to allow a
22070 'trusted' set of users access to management capabilities without
22073 Defaults to @samp{"root"}.
22077 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
22078 UNIX socket permissions for the R/O socket. This is used for monitoring
22081 Defaults to @samp{"0777"}.
22085 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
22086 UNIX socket permissions for the R/W socket. Default allows only root.
22087 If PolicyKit is enabled on the socket, the default will change to allow
22088 everyone (eg, 0777)
22090 Defaults to @samp{"0770"}.
22094 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
22095 UNIX socket permissions for the admin socket. Default allows only owner
22096 (root), do not change it unless you are sure to whom you are exposing
22099 Defaults to @samp{"0777"}.
22103 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
22104 The directory in which sockets will be found/created.
22106 Defaults to @samp{"/var/run/libvirt"}.
22110 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
22111 Authentication scheme for UNIX read-only sockets. By default socket
22112 permissions allow anyone to connect
22114 Defaults to @samp{"polkit"}.
22118 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
22119 Authentication scheme for UNIX read-write sockets. By default socket
22120 permissions only allow root. If PolicyKit support was compiled into
22121 libvirt, the default will be to use 'polkit' auth.
22123 Defaults to @samp{"polkit"}.
22127 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
22128 Authentication scheme for TCP sockets. If you don't enable SASL, then
22129 all TCP traffic is cleartext. Don't do this outside of a dev/test
22132 Defaults to @samp{"sasl"}.
22136 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
22137 Authentication scheme for TLS sockets. TLS sockets already have
22138 encryption provided by the TLS layer, and limited authentication is done
22141 It is possible to make use of any SASL authentication mechanism as well,
22142 by using 'sasl' for this option
22144 Defaults to @samp{"none"}.
22148 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
22149 API access control scheme.
22151 By default an authenticated user is allowed access to all APIs. Access
22152 drivers can place restrictions on this.
22154 Defaults to @samp{()}.
22158 @deftypevr {@code{libvirt-configuration} parameter} string key-file
22159 Server key file path. If set to an empty string, then no private key is
22162 Defaults to @samp{""}.
22166 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
22167 Server key file path. If set to an empty string, then no certificate is
22170 Defaults to @samp{""}.
22174 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
22175 Server key file path. If set to an empty string, then no CA certificate
22178 Defaults to @samp{""}.
22182 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
22183 Certificate revocation list path. If set to an empty string, then no
22186 Defaults to @samp{""}.
22190 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
22191 Disable verification of our own server certificates.
22193 When libvirtd starts it performs some sanity checks against its own
22196 Defaults to @samp{#f}.
22200 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
22201 Disable verification of client certificates.
22203 Client certificate verification is the primary authentication mechanism.
22204 Any client which does not present a certificate signed by the CA will be
22207 Defaults to @samp{#f}.
22211 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
22212 Whitelist of allowed x509 Distinguished Name.
22214 Defaults to @samp{()}.
22218 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
22219 Whitelist of allowed SASL usernames. The format for username depends on
22220 the SASL authentication mechanism.
22222 Defaults to @samp{()}.
22226 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
22227 Override the compile time default TLS priority string. The default is
22228 usually "NORMAL" unless overridden at build time. Only set this is it
22229 is desired for libvirt to deviate from the global default settings.
22231 Defaults to @samp{"NORMAL"}.
22235 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
22236 Maximum number of concurrent client connections to allow over all
22239 Defaults to @samp{5000}.
22243 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
22244 Maximum length of queue of connections waiting to be accepted by the
22245 daemon. Note, that some protocols supporting retransmission may obey
22246 this so that a later reattempt at connection succeeds.
22248 Defaults to @samp{1000}.
22252 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
22253 Maximum length of queue of accepted but not yet authenticated clients.
22254 Set this to zero to turn this feature off
22256 Defaults to @samp{20}.
22260 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
22261 Number of workers to start up initially.
22263 Defaults to @samp{5}.
22267 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
22268 Maximum number of worker threads.
22270 If the number of active clients exceeds @code{min-workers}, then more
22271 threads are spawned, up to max_workers limit. Typically you'd want
22272 max_workers to equal maximum number of clients allowed.
22274 Defaults to @samp{20}.
22278 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
22279 Number of priority workers. If all workers from above pool are stuck,
22280 some calls marked as high priority (notably domainDestroy) can be
22281 executed in this pool.
22283 Defaults to @samp{5}.
22287 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
22288 Total global limit on concurrent RPC calls.
22290 Defaults to @samp{20}.
22294 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
22295 Limit on concurrent requests from a single client connection. To avoid
22296 one client monopolizing the server this should be a small fraction of
22297 the global max_requests and max_workers parameter.
22299 Defaults to @samp{5}.
22303 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
22304 Same as @code{min-workers} but for the admin interface.
22306 Defaults to @samp{1}.
22310 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
22311 Same as @code{max-workers} but for the admin interface.
22313 Defaults to @samp{5}.
22317 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
22318 Same as @code{max-clients} but for the admin interface.
22320 Defaults to @samp{5}.
22324 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
22325 Same as @code{max-queued-clients} but for the admin interface.
22327 Defaults to @samp{5}.
22331 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
22332 Same as @code{max-client-requests} but for the admin interface.
22334 Defaults to @samp{5}.
22338 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
22339 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22341 Defaults to @samp{3}.
22345 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
22348 A filter allows to select a different logging level for a given category
22349 of logs The format for a filter is one of:
22360 where @code{name} is a string which is matched against the category
22361 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22362 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22363 be a substring of the full category name, in order to match multiple
22364 similar categories), the optional "+" prefix tells libvirt to log stack
22365 trace for each message matching name, and @code{x} is the minimal level
22366 where matching messages should be logged:
22383 Multiple filters can be defined in a single filters statement, they just
22384 need to be separated by spaces.
22386 Defaults to @samp{"3:remote 4:event"}.
22390 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
22393 An output is one of the places to save logging information. The format
22394 for an output can be:
22398 output goes to stderr
22400 @item x:syslog:name
22401 use syslog for the output and use the given name as the ident
22403 @item x:file:file_path
22404 output to a file, with the given filepath
22407 output to journald logging system
22411 In all case the x prefix is the minimal level, acting as a filter
22428 Multiple outputs can be defined, they just need to be separated by
22431 Defaults to @samp{"3:stderr"}.
22435 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
22436 Allows usage of the auditing subsystem to be altered
22440 0: disable all auditing
22443 1: enable auditing, only if enabled on host
22446 2: enable auditing, and exit if disabled on host.
22450 Defaults to @samp{1}.
22454 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
22455 Send audit messages via libvirt logging infrastructure.
22457 Defaults to @samp{#f}.
22461 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
22462 Host UUID. UUID must not have all digits be the same.
22464 Defaults to @samp{""}.
22468 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
22469 Source to read host UUID.
22473 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
22476 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
22480 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
22483 Defaults to @samp{"smbios"}.
22487 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
22488 A keepalive message is sent to a client after @code{keepalive_interval}
22489 seconds of inactivity to check if the client is still responding. If
22490 set to -1, libvirtd will never send keepalive requests; however clients
22491 can still send them and the daemon will send responses.
22493 Defaults to @samp{5}.
22497 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
22498 Maximum number of keepalive messages that are allowed to be sent to the
22499 client without getting any response before the connection is considered
22502 In other words, the connection is automatically closed approximately
22503 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
22504 the last message received from the client. When @code{keepalive-count}
22505 is set to 0, connections will be automatically closed after
22506 @code{keepalive-interval} seconds of inactivity without sending any
22507 keepalive messages.
22509 Defaults to @samp{5}.
22513 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
22514 Same as above but for admin interface.
22516 Defaults to @samp{5}.
22520 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
22521 Same as above but for admin interface.
22523 Defaults to @samp{5}.
22527 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
22528 Timeout for Open vSwitch calls.
22530 The @code{ovs-vsctl} utility is used for the configuration and its
22531 timeout option is set by default to 5 seconds to avoid potential
22532 infinite waits blocking libvirt.
22534 Defaults to @samp{5}.
22538 @c %end of autogenerated docs
22540 @subsubheading Virtlog daemon
22541 The virtlogd service is a server side daemon component of libvirt that is
22542 used to manage logs from virtual machine consoles.
22544 This daemon is not used directly by libvirt client applications, rather it
22545 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
22546 standalone daemon, the main @code{libvirtd} daemon can be restarted without
22547 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
22548 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
22550 @deffn {Scheme Variable} virtlog-service-type
22551 This is the type of the virtlog daemon.
22552 Its value must be a @code{virtlog-configuration}.
22555 (service virtlog-service-type
22556 (virtlog-configuration
22557 (max-clients 1000)))
22561 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
22562 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22564 Defaults to @samp{3}.
22568 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
22571 A filter allows to select a different logging level for a given category
22572 of logs The format for a filter is one of:
22583 where @code{name} is a string which is matched against the category
22584 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22585 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22586 be a substring of the full category name, in order to match multiple
22587 similar categories), the optional "+" prefix tells libvirt to log stack
22588 trace for each message matching name, and @code{x} is the minimal level
22589 where matching messages should be logged:
22606 Multiple filters can be defined in a single filters statement, they just
22607 need to be separated by spaces.
22609 Defaults to @samp{"3:remote 4:event"}.
22613 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
22616 An output is one of the places to save logging information The format
22617 for an output can be:
22621 output goes to stderr
22623 @item x:syslog:name
22624 use syslog for the output and use the given name as the ident
22626 @item x:file:file_path
22627 output to a file, with the given filepath
22630 output to journald logging system
22634 In all case the x prefix is the minimal level, acting as a filter
22651 Multiple outputs can be defined, they just need to be separated by
22654 Defaults to @samp{"3:stderr"}.
22658 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
22659 Maximum number of concurrent client connections to allow over all
22662 Defaults to @samp{1024}.
22666 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
22667 Maximum file size before rolling over.
22669 Defaults to @samp{2MB}
22673 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
22674 Maximum number of backup files to keep.
22676 Defaults to @samp{3}
22680 @subsubheading Transparent Emulation with QEMU
22683 @cindex @code{binfmt_misc}
22684 @code{qemu-binfmt-service-type} provides support for transparent
22685 emulation of program binaries built for different architectures---e.g.,
22686 it allows you to transparently execute an ARMv7 program on an x86_64
22687 machine. It achieves this by combining the @uref{https://www.qemu.org,
22688 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
22690 @defvr {Scheme Variable} qemu-binfmt-service-type
22691 This is the type of the QEMU/binfmt service for transparent emulation.
22692 Its value must be a @code{qemu-binfmt-configuration} object, which
22693 specifies the QEMU package to use as well as the architecture we want to
22697 (service qemu-binfmt-service-type
22698 (qemu-binfmt-configuration
22699 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
22702 In this example, we enable transparent emulation for the ARM and aarch64
22703 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
22704 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
22705 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
22708 @deftp {Data Type} qemu-binfmt-configuration
22709 This is the configuration for the @code{qemu-binfmt} service.
22712 @item @code{platforms} (default: @code{'()})
22713 The list of emulated QEMU platforms. Each item must be a @dfn{platform
22714 object} as returned by @code{lookup-qemu-platforms} (see below).
22716 @item @code{guix-support?} (default: @code{#f})
22717 When it is true, QEMU and all its dependencies are added to the build
22718 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
22719 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
22720 handlers to be used within the build environment, which in turn means
22721 that you can transparently build programs for another architecture.
22723 For example, let's suppose you're on an x86_64 machine and you have this
22727 (service qemu-binfmt-service-type
22728 (qemu-binfmt-configuration
22729 (platforms (lookup-qemu-platforms "arm"))
22730 (guix-support? #t)))
22736 guix build -s armhf-linux inkscape
22740 and it will build Inkscape for ARMv7 @emph{as if it were a native
22741 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
22742 if you'd like to test a package build for an architecture you don't have
22745 @item @code{qemu} (default: @code{qemu})
22746 The QEMU package to use.
22750 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
22751 Return the list of QEMU platform objects corresponding to
22752 @var{platforms}@dots{}. @var{platforms} must be a list of strings
22753 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
22754 @code{"mips64el"}, and so on.
22757 @deffn {Scheme Procedure} qemu-platform? @var{obj}
22758 Return true if @var{obj} is a platform object.
22761 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
22762 Return the name of @var{platform}---a string such as @code{"arm"}.
22765 @node Version Control Services
22766 @subsection Version Control Services
22768 The @code{(gnu services version-control)} module provides a service to
22769 allow remote access to local Git repositories. There are three options:
22770 the @code{git-daemon-service}, which provides access to repositories via
22771 the @code{git://} unsecured TCP-based protocol, extending the
22772 @code{nginx} web server to proxy some requests to
22773 @code{git-http-backend}, or providing a web interface with
22774 @code{cgit-service-type}.
22776 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
22778 Return a service that runs @command{git daemon}, a simple TCP server to
22779 expose repositories over the Git protocol for anonymous access.
22781 The optional @var{config} argument should be a
22782 @code{<git-daemon-configuration>} object, by default it allows read-only
22783 access to exported@footnote{By creating the magic file
22784 "git-daemon-export-ok" in the repository directory.} repositories under
22789 @deftp {Data Type} git-daemon-configuration
22790 Data type representing the configuration for @code{git-daemon-service}.
22793 @item @code{package} (default: @var{git})
22794 Package object of the Git distributed version control system.
22796 @item @code{export-all?} (default: @var{#f})
22797 Whether to allow access for all Git repositories, even if they do not
22798 have the @file{git-daemon-export-ok} file.
22800 @item @code{base-path} (default: @file{/srv/git})
22801 Whether to remap all the path requests as relative to the given path.
22802 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
22803 then if you later try to pull @code{git://example.com/hello.git}, git
22804 daemon will interpret the path as @code{/srv/git/hello.git}.
22806 @item @code{user-path} (default: @var{#f})
22807 Whether to allow @code{~user} notation to be used in requests. When
22808 specified with empty string, requests to @code{git://host/~alice/foo} is
22809 taken as a request to access @code{foo} repository in the home directory
22810 of user @code{alice}. If @var{(user-path "path")} is specified, the
22811 same request is taken as a request to access @code{path/foo} repository
22812 in the home directory of user @code{alice}.
22814 @item @code{listen} (default: @var{'()})
22815 Whether to listen on specific IP addresses or hostnames, defaults to
22818 @item @code{port} (default: @var{#f})
22819 Whether to listen on an alternative port, which defaults to 9418.
22821 @item @code{whitelist} (default: @var{'()})
22822 If not empty, only allow access to this list of directories.
22824 @item @code{extra-options} (default: @var{'()})
22825 Extra options will be passed to @code{git daemon}, please run
22826 @command{man git-daemon} for more information.
22831 The @code{git://} protocol lacks authentication. When you pull from a
22832 repository fetched via @code{git://}, you don't know whether the data you
22833 receive was modified or is even coming from the specified host, and your
22834 connection is subject to eavesdropping. It's better to use an authenticated
22835 and encrypted transport, such as @code{https}. Although Git allows you
22836 to serve repositories using unsophisticated file-based web servers,
22837 there is a faster protocol implemented by the @code{git-http-backend}
22838 program. This program is the back-end of a proper Git web service. It
22839 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
22840 on running the necessary @code{fcgiwrap} daemon.
22842 Guix has a separate configuration data type for serving Git repositories
22845 @deftp {Data Type} git-http-configuration
22846 Data type representing the configuration for @code{git-http-service}.
22849 @item @code{package} (default: @var{git})
22850 Package object of the Git distributed version control system.
22852 @item @code{git-root} (default: @file{/srv/git})
22853 Directory containing the Git repositories to expose to the world.
22855 @item @code{export-all?} (default: @var{#f})
22856 Whether to expose access for all Git repositories in @var{git-root},
22857 even if they do not have the @file{git-daemon-export-ok} file.
22859 @item @code{uri-path} (default: @file{/git/})
22860 Path prefix for Git access. With the default @code{/git/} prefix, this
22861 will map @code{http://@var{server}/git/@var{repo}.git} to
22862 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
22863 with this prefix are not passed on to this Git instance.
22865 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
22866 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
22871 There is no @code{git-http-service-type}, currently; instead you can
22872 create an @code{nginx-location-configuration} from a
22873 @code{git-http-configuration} and then add that location to a web
22876 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
22877 [config=(git-http-configuration)]
22878 Compute an @code{nginx-location-configuration} that corresponds to the
22879 given Git http configuration. An example nginx service definition to
22880 serve the default @file{/srv/git} over HTTPS might be:
22883 (service nginx-service-type
22884 (nginx-configuration
22887 (nginx-server-configuration
22888 (listen '("443 ssl"))
22889 (server-name "git.my-host.org")
22891 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
22892 (ssl-certificate-key
22893 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
22896 (git-http-nginx-location-configuration
22897 (git-http-configuration (uri-path "/"))))))))))
22900 This example assumes that you are using Let's Encrypt to get your TLS
22901 certificate. @xref{Certificate Services}. The default @code{certbot}
22902 service will redirect all HTTP traffic on @code{git.my-host.org} to
22903 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
22904 system services. @xref{Web Services}.
22907 @subsubheading Cgit Service
22909 @cindex Cgit service
22910 @cindex Git, web interface
22911 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
22912 repositories written in C.
22914 The following example will configure the service with default values.
22915 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
22918 (service cgit-service-type)
22921 The @code{file-object} type designates either a file-like object
22922 (@pxref{G-Expressions, file-like objects}) or a string.
22924 @c %start of fragment
22926 Available @code{cgit-configuration} fields are:
22928 @deftypevr {@code{cgit-configuration} parameter} package package
22933 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
22934 NGINX configuration.
22938 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
22939 Specifies a command which will be invoked to format the content of about
22940 pages (both top-level and for each repository).
22942 Defaults to @samp{""}.
22946 @deftypevr {@code{cgit-configuration} parameter} string agefile
22947 Specifies a path, relative to each repository path, which can be used to
22948 specify the date and time of the youngest commit in the repository.
22950 Defaults to @samp{""}.
22954 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
22955 Specifies a command that will be invoked for authenticating repository
22958 Defaults to @samp{""}.
22962 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
22963 Flag which, when set to @samp{age}, enables date ordering in the branch
22964 ref list, and when set @samp{name} enables ordering by branch name.
22966 Defaults to @samp{"name"}.
22970 @deftypevr {@code{cgit-configuration} parameter} string cache-root
22971 Path used to store the cgit cache entries.
22973 Defaults to @samp{"/var/cache/cgit"}.
22977 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
22978 Number which specifies the time-to-live, in minutes, for the cached
22979 version of repository pages accessed with a fixed SHA1.
22981 Defaults to @samp{-1}.
22985 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
22986 Number which specifies the time-to-live, in minutes, for the cached
22987 version of repository pages accessed without a fixed SHA1.
22989 Defaults to @samp{5}.
22993 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
22994 Number which specifies the time-to-live, in minutes, for the cached
22995 version of the repository summary page.
22997 Defaults to @samp{5}.
23001 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
23002 Number which specifies the time-to-live, in minutes, for the cached
23003 version of the repository index page.
23005 Defaults to @samp{5}.
23009 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
23010 Number which specifies the time-to-live, in minutes, for the result of
23011 scanning a path for Git repositories.
23013 Defaults to @samp{15}.
23017 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
23018 Number which specifies the time-to-live, in minutes, for the cached
23019 version of the repository about page.
23021 Defaults to @samp{15}.
23025 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
23026 Number which specifies the time-to-live, in minutes, for the cached
23027 version of snapshots.
23029 Defaults to @samp{5}.
23033 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
23034 The maximum number of entries in the cgit cache. When set to @samp{0},
23035 caching is disabled.
23037 Defaults to @samp{0}.
23041 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
23042 Sort items in the repo list case sensitively.
23044 Defaults to @samp{#t}.
23048 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
23049 List of common prefixes which, when combined with a repository URL,
23050 generates valid clone URLs for the repository.
23052 Defaults to @samp{()}.
23056 @deftypevr {@code{cgit-configuration} parameter} list clone-url
23057 List of @code{clone-url} templates.
23059 Defaults to @samp{()}.
23063 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
23064 Command which will be invoked to format commit messages.
23066 Defaults to @samp{""}.
23070 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
23071 Flag which, when set to @samp{date}, enables strict date ordering in the
23072 commit log, and when set to @samp{topo} enables strict topological
23075 Defaults to @samp{"git log"}.
23079 @deftypevr {@code{cgit-configuration} parameter} file-object css
23080 URL which specifies the css document to include in all cgit pages.
23082 Defaults to @samp{"/share/cgit/cgit.css"}.
23086 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
23087 Specifies a command which will be invoked to format names and email
23088 address of committers, authors, and taggers, as represented in various
23089 places throughout the cgit interface.
23091 Defaults to @samp{""}.
23095 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
23096 Flag which, when set to @samp{#t}, will make cgit generate a HTML
23097 fragment suitable for embedding in other HTML pages.
23099 Defaults to @samp{#f}.
23103 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
23104 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
23105 commit history graph to the left of the commit messages in the
23106 repository log page.
23108 Defaults to @samp{#f}.
23112 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
23113 Flag which, when set to @samp{#t}, allows all filter settings to be
23114 overridden in repository-specific cgitrc files.
23116 Defaults to @samp{#f}.
23120 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
23121 Flag which, when set to @samp{#t}, allows users to follow a file in the
23124 Defaults to @samp{#f}.
23128 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
23129 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
23132 Defaults to @samp{#t}.
23136 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
23137 Flag which, when set to @samp{#t}, will make cgit generate extra links
23138 "summary", "commit", "tree" for each repo in the repository index.
23140 Defaults to @samp{#f}.
23144 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
23145 Flag which, when set to @samp{#t}, will make cgit display the owner of
23146 each repo in the repository index.
23148 Defaults to @samp{#t}.
23152 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
23153 Flag which, when set to @samp{#t}, will make cgit print the number of
23154 modified files for each commit on the repository log page.
23156 Defaults to @samp{#f}.
23160 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
23161 Flag which, when set to @samp{#t}, will make cgit print the number of
23162 added and removed lines for each commit on the repository log page.
23164 Defaults to @samp{#f}.
23168 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
23169 Flag which, when set to @code{#t}, will make cgit display remote
23170 branches in the summary and refs views.
23172 Defaults to @samp{#f}.
23176 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
23177 Flag which, when set to @code{1}, will make cgit use the subject of the
23178 parent commit as link text when generating links to parent commits in
23181 Defaults to @samp{#f}.
23185 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
23186 Flag which, when set to @samp{#t}, will make cgit use the subject of the
23187 parent commit as link text when generating links to parent commits in
23190 Defaults to @samp{#f}.
23194 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
23195 Flag which, when set to @samp{#t}, will make cgit generate linenumber
23196 links for plaintext blobs printed in the tree view.
23198 Defaults to @samp{#t}.
23202 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
23203 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
23204 set any repo specific settings.
23206 Defaults to @samp{#f}.
23210 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
23211 URL used as link to a shortcut icon for cgit.
23213 Defaults to @samp{"/favicon.ico"}.
23217 @deftypevr {@code{cgit-configuration} parameter} string footer
23218 The content of the file specified with this option will be included
23219 verbatim at the bottom of all pages (i.e.@: it replaces the standard
23220 "generated by..."@: message).
23222 Defaults to @samp{""}.
23226 @deftypevr {@code{cgit-configuration} parameter} string head-include
23227 The content of the file specified with this option will be included
23228 verbatim in the HTML HEAD section on all pages.
23230 Defaults to @samp{""}.
23234 @deftypevr {@code{cgit-configuration} parameter} string header
23235 The content of the file specified with this option will be included
23236 verbatim at the top of all pages.
23238 Defaults to @samp{""}.
23242 @deftypevr {@code{cgit-configuration} parameter} file-object include
23243 Name of a configfile to include before the rest of the current config-
23246 Defaults to @samp{""}.
23250 @deftypevr {@code{cgit-configuration} parameter} string index-header
23251 The content of the file specified with this option will be included
23252 verbatim above the repository index.
23254 Defaults to @samp{""}.
23258 @deftypevr {@code{cgit-configuration} parameter} string index-info
23259 The content of the file specified with this option will be included
23260 verbatim below the heading on the repository index page.
23262 Defaults to @samp{""}.
23266 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
23267 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
23268 in the servers timezone.
23270 Defaults to @samp{#f}.
23274 @deftypevr {@code{cgit-configuration} parameter} file-object logo
23275 URL which specifies the source of an image which will be used as a logo
23278 Defaults to @samp{"/share/cgit/cgit.png"}.
23282 @deftypevr {@code{cgit-configuration} parameter} string logo-link
23283 URL loaded when clicking on the cgit logo image.
23285 Defaults to @samp{""}.
23289 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
23290 Command which will be invoked to format the Owner column of the main
23293 Defaults to @samp{""}.
23297 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
23298 Number of items to display in atom feeds view.
23300 Defaults to @samp{10}.
23304 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
23305 Number of entries to list per page in "log" view.
23307 Defaults to @samp{50}.
23311 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
23312 Number of commit message characters to display in "log" view.
23314 Defaults to @samp{80}.
23318 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
23319 Specifies the number of entries to list per page on the repository index
23322 Defaults to @samp{50}.
23326 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
23327 Specifies the maximum number of repo description characters to display
23328 on the repository index page.
23330 Defaults to @samp{80}.
23334 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
23335 Specifies the maximum size of a blob to display HTML for in KBytes.
23337 Defaults to @samp{0}.
23341 @deftypevr {@code{cgit-configuration} parameter} string max-stats
23342 Maximum statistics period. Valid values are @samp{week},@samp{month},
23343 @samp{quarter} and @samp{year}.
23345 Defaults to @samp{""}.
23349 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
23350 Mimetype for the specified filename extension.
23352 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
23353 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
23354 "image/png") (svg "image/svg+xml"))}.
23358 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
23359 Specifies the file to use for automatic mimetype lookup.
23361 Defaults to @samp{""}.
23365 @deftypevr {@code{cgit-configuration} parameter} string module-link
23366 Text which will be used as the formatstring for a hyperlink when a
23367 submodule is printed in a directory listing.
23369 Defaults to @samp{""}.
23373 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
23374 If set to the value @samp{#t} caching will be disabled.
23376 Defaults to @samp{#f}.
23380 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
23381 If set to @samp{#t} showing full author email addresses will be
23384 Defaults to @samp{#f}.
23388 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
23389 Flag which, when set to @samp{#t}, will make cgit omit the standard
23390 header on all pages.
23392 Defaults to @samp{#f}.
23396 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
23397 A list of subdirectories inside of @code{repository-directory}, relative
23398 to it, that should loaded as Git repositories. An empty list means that
23399 all subdirectories will be loaded.
23401 Defaults to @samp{()}.
23405 @deftypevr {@code{cgit-configuration} parameter} file-object readme
23406 Text which will be used as default value for @code{cgit-repo-readme}.
23408 Defaults to @samp{""}.
23412 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
23413 If set to @code{#t} and @code{repository-directory} is enabled, if any
23414 repositories are found with a suffix of @code{.git}, this suffix will be
23415 removed for the URL and name.
23417 Defaults to @samp{#f}.
23421 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
23422 Maximum number of files to consider when detecting renames.
23424 Defaults to @samp{-1}.
23428 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
23429 The way in which repositories in each section are sorted.
23431 Defaults to @samp{""}.
23435 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
23436 Text used as content for the @code{robots} meta-tag.
23438 Defaults to @samp{("noindex" "nofollow")}.
23442 @deftypevr {@code{cgit-configuration} parameter} string root-desc
23443 Text printed below the heading on the repository index page.
23445 Defaults to @samp{"a fast webinterface for the git dscm"}.
23449 @deftypevr {@code{cgit-configuration} parameter} string root-readme
23450 The content of the file specified with this option will be included
23451 verbatim below thef "about" link on the repository index page.
23453 Defaults to @samp{""}.
23457 @deftypevr {@code{cgit-configuration} parameter} string root-title
23458 Text printed as heading on the repository index page.
23460 Defaults to @samp{""}.
23464 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
23465 If set to @samp{#t} and repository-directory is enabled,
23466 repository-directory will recurse into directories whose name starts
23467 with a period. Otherwise, repository-directory will stay away from such
23468 directories, considered as "hidden". Note that this does not apply to
23469 the ".git" directory in non-bare repos.
23471 Defaults to @samp{#f}.
23475 @deftypevr {@code{cgit-configuration} parameter} list snapshots
23476 Text which specifies the default set of snapshot formats that cgit
23477 generates links for.
23479 Defaults to @samp{()}.
23483 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
23484 Name of the directory to scan for repositories (represents
23487 Defaults to @samp{"/srv/git"}.
23491 @deftypevr {@code{cgit-configuration} parameter} string section
23492 The name of the current repository section - all repositories defined
23493 after this option will inherit the current section name.
23495 Defaults to @samp{""}.
23499 @deftypevr {@code{cgit-configuration} parameter} string section-sort
23500 Flag which, when set to @samp{1}, will sort the sections on the
23501 repository listing by name.
23503 Defaults to @samp{""}.
23507 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
23508 A number which, if defined prior to repository-directory, specifies how
23509 many path elements from each repo path to use as a default section name.
23511 Defaults to @samp{0}.
23515 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
23516 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
23519 Defaults to @samp{#f}.
23523 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
23524 Specifies a command which will be invoked to format plaintext blobs in
23527 Defaults to @samp{""}.
23531 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
23532 Specifies the number of branches to display in the repository "summary"
23535 Defaults to @samp{10}.
23539 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
23540 Specifies the number of log entries to display in the repository
23543 Defaults to @samp{10}.
23547 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
23548 Specifies the number of tags to display in the repository "summary"
23551 Defaults to @samp{10}.
23555 @deftypevr {@code{cgit-configuration} parameter} string strict-export
23556 Filename which, if specified, needs to be present within the repository
23557 for cgit to allow access to that repository.
23559 Defaults to @samp{""}.
23563 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
23564 URL which, if specified, will be used as root for all cgit links.
23566 Defaults to @samp{"/"}.
23570 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
23571 A list of @dfn{cgit-repo} records to use with config.
23573 Defaults to @samp{()}.
23575 Available @code{repository-cgit-configuration} fields are:
23577 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
23578 A mask of snapshot formats for this repo that cgit generates links for,
23579 restricted by the global @code{snapshots} setting.
23581 Defaults to @samp{()}.
23585 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
23586 Override the default @code{source-filter}.
23588 Defaults to @samp{""}.
23592 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
23593 The relative URL used to access the repository.
23595 Defaults to @samp{""}.
23599 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
23600 Override the default @code{about-filter}.
23602 Defaults to @samp{""}.
23606 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
23607 Flag which, when set to @samp{age}, enables date ordering in the branch
23608 ref list, and when set to @samp{name} enables ordering by branch name.
23610 Defaults to @samp{""}.
23614 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
23615 A list of URLs which can be used to clone repo.
23617 Defaults to @samp{()}.
23621 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
23622 Override the default @code{commit-filter}.
23624 Defaults to @samp{""}.
23628 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
23629 Flag which, when set to @samp{date}, enables strict date ordering in the
23630 commit log, and when set to @samp{topo} enables strict topological
23633 Defaults to @samp{""}.
23637 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
23638 The name of the default branch for this repository. If no such branch
23639 exists in the repository, the first branch name (when sorted) is used as
23640 default instead. By default branch pointed to by HEAD, or "master" if
23641 there is no suitable HEAD.
23643 Defaults to @samp{""}.
23647 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
23648 The value to show as repository description.
23650 Defaults to @samp{""}.
23654 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
23655 The value to show as repository homepage.
23657 Defaults to @samp{""}.
23661 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
23662 Override the default @code{email-filter}.
23664 Defaults to @samp{""}.
23668 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
23669 A flag which can be used to disable the global setting
23670 @code{enable-commit-graph?}.
23672 Defaults to @samp{disabled}.
23676 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
23677 A flag which can be used to disable the global setting
23678 @code{enable-log-filecount?}.
23680 Defaults to @samp{disabled}.
23684 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
23685 A flag which can be used to disable the global setting
23686 @code{enable-log-linecount?}.
23688 Defaults to @samp{disabled}.
23692 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
23693 Flag which, when set to @code{#t}, will make cgit display remote
23694 branches in the summary and refs views.
23696 Defaults to @samp{disabled}.
23700 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
23701 A flag which can be used to override the global setting
23702 @code{enable-subject-links?}.
23704 Defaults to @samp{disabled}.
23708 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
23709 A flag which can be used to override the global setting
23710 @code{enable-html-serving?}.
23712 Defaults to @samp{disabled}.
23716 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
23717 Flag which, when set to @code{#t}, hides the repository from the
23720 Defaults to @samp{#f}.
23724 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
23725 Flag which, when set to @samp{#t}, ignores the repository.
23727 Defaults to @samp{#f}.
23731 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
23732 URL which specifies the source of an image which will be used as a logo
23733 on this repo’s pages.
23735 Defaults to @samp{""}.
23739 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
23740 URL loaded when clicking on the cgit logo image.
23742 Defaults to @samp{""}.
23746 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
23747 Override the default @code{owner-filter}.
23749 Defaults to @samp{""}.
23753 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
23754 Text which will be used as the formatstring for a hyperlink when a
23755 submodule is printed in a directory listing. The arguments for the
23756 formatstring are the path and SHA1 of the submodule commit.
23758 Defaults to @samp{""}.
23762 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
23763 Text which will be used as the formatstring for a hyperlink when a
23764 submodule with the specified subdirectory path is printed in a directory
23767 Defaults to @samp{()}.
23771 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
23772 Override the default maximum statistics period.
23774 Defaults to @samp{""}.
23778 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
23779 The value to show as repository name.
23781 Defaults to @samp{""}.
23785 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
23786 A value used to identify the owner of the repository.
23788 Defaults to @samp{""}.
23792 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
23793 An absolute path to the repository directory.
23795 Defaults to @samp{""}.
23799 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
23800 A path (relative to repo) which specifies a file to include verbatim as
23801 the "About" page for this repo.
23803 Defaults to @samp{""}.
23807 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
23808 The name of the current repository section - all repositories defined
23809 after this option will inherit the current section name.
23811 Defaults to @samp{""}.
23815 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
23816 Extra options will be appended to cgitrc file.
23818 Defaults to @samp{()}.
23824 @deftypevr {@code{cgit-configuration} parameter} list extra-options
23825 Extra options will be appended to cgitrc file.
23827 Defaults to @samp{()}.
23832 @c %end of fragment
23834 However, it could be that you just want to get a @code{cgitrc} up and
23835 running. In that case, you can pass an @code{opaque-cgit-configuration}
23836 as a record to @code{cgit-service-type}. As its name indicates, an
23837 opaque configuration does not have easy reflective capabilities.
23839 Available @code{opaque-cgit-configuration} fields are:
23841 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
23845 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
23846 The contents of the @code{cgitrc}, as a string.
23849 For example, if your @code{cgitrc} is just the empty string, you
23850 could instantiate a cgit service like this:
23853 (service cgit-service-type
23854 (opaque-cgit-configuration
23858 @subsubheading Gitolite Service
23860 @cindex Gitolite service
23861 @cindex Git, hosting
23862 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
23863 repositories on a central server.
23865 Gitolite can handle multiple repositories and users, and supports flexible
23866 configuration of the permissions for the users on the repositories.
23868 The following example will configure Gitolite using the default @code{git}
23869 user, and the provided SSH public key.
23872 (service gitolite-service-type
23873 (gitolite-configuration
23874 (admin-pubkey (plain-file
23876 "ssh-rsa AAAA... guix@@example.com"))))
23879 Gitolite is configured through a special admin repository which you can clone,
23880 for example, if you setup Gitolite on @code{example.com}, you would run the
23881 following command to clone the admin repository.
23884 git clone git@@example.com:gitolite-admin
23887 When the Gitolite service is activated, the provided @code{admin-pubkey} will
23888 be inserted in to the @file{keydir} directory in the gitolite-admin
23889 repository. If this results in a change in the repository, it will be
23890 committed using the message ``gitolite setup by GNU Guix''.
23892 @deftp {Data Type} gitolite-configuration
23893 Data type representing the configuration for @code{gitolite-service-type}.
23896 @item @code{package} (default: @var{gitolite})
23897 Gitolite package to use.
23899 @item @code{user} (default: @var{git})
23900 User to use for Gitolite. This will be user that you use when accessing
23903 @item @code{group} (default: @var{git})
23904 Group to use for Gitolite.
23906 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
23907 Directory in which to store the Gitolite configuration and repositories.
23909 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
23910 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
23911 representing the configuration for Gitolite.
23913 @item @code{admin-pubkey} (default: @var{#f})
23914 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
23915 setup Gitolite. This will be inserted in to the @file{keydir} directory
23916 within the gitolite-admin repository.
23918 To specify the SSH key as a string, use the @code{plain-file} function.
23921 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
23927 @deftp {Data Type} gitolite-rc-file
23928 Data type representing the Gitolite RC file.
23931 @item @code{umask} (default: @code{#o0077})
23932 This controls the permissions Gitolite sets on the repositories and their
23935 A value like @code{#o0027} will give read access to the group used by Gitolite
23936 (by default: @code{git}). This is necessary when using Gitolite with software
23937 like cgit or gitweb.
23939 @item @code{git-config-keys} (default: @code{""})
23940 Gitolite allows you to set git config values using the "config" keyword. This
23941 setting allows control over the config keys to accept.
23943 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
23944 Set the role names allowed to be used by users running the perms command.
23946 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
23947 This setting controls the commands and features to enable within Gitolite.
23953 @node Game Services
23954 @subsection Game Services
23956 @subsubheading The Battle for Wesnoth Service
23958 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
23959 based tactical strategy game, with several single player campaigns, and
23960 multiplayer games (both networked and local).
23962 @defvar {Scheme Variable} wesnothd-service-type
23963 Service type for the wesnothd service. Its value must be a
23964 @code{wesnothd-configuration} object. To run wesnothd in the default
23965 configuration, instantiate it as:
23968 (service wesnothd-service-type)
23972 @deftp {Data Type} wesnothd-configuration
23973 Data type representing the configuration of @command{wesnothd}.
23976 @item @code{package} (default: @code{wesnoth-server})
23977 The wesnoth server package to use.
23979 @item @code{port} (default: @code{15000})
23980 The port to bind the server to.
23984 @node Miscellaneous Services
23985 @subsection Miscellaneous Services
23987 @cindex fingerprint
23988 @subsubheading Fingerprint Service
23990 The @code{(gnu services authentication)} module provides a DBus service to
23991 read and identify fingerprints via a fingerprint sensor.
23993 @defvr {Scheme Variable} fprintd-service-type
23994 The service type for @command{fprintd}, which provides the fingerprint
23995 reading capability.
23998 (service fprintd-service-type)
24003 @subsubheading System Control Service
24005 The @code{(gnu services sysctl)} provides a service to configure kernel
24006 parameters at boot.
24008 @defvr {Scheme Variable} sysctl-service-type
24009 The service type for @command{sysctl}, which modifies kernel parameters
24010 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
24014 (service sysctl-service-type
24015 (sysctl-configuration
24016 (settings '(("net.ipv4.ip_forward" . "1")))))
24020 @deftp {Data Type} sysctl-configuration
24021 The data type representing the configuration of @command{sysctl}.
24024 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
24025 The @command{sysctl} executable to use.
24027 @item @code{settings} (default: @code{'()})
24028 An association list specifies kernel parameters and their values.
24033 @subsubheading PC/SC Smart Card Daemon Service
24035 The @code{(gnu services security-token)} module provides the following service
24036 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
24037 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
24038 manager that coordinates communications with smart card readers, smart cards
24039 and cryptographic tokens that are connected to the system.
24041 @defvr {Scheme Variable} pcscd-service-type
24042 Service type for the @command{pcscd} service. Its value must be a
24043 @code{pcscd-configuration} object. To run pcscd in the default
24044 configuration, instantiate it as:
24047 (service pcscd-service-type)
24051 @deftp {Data Type} pcscd-configuration
24052 The data type representing the configuration of @command{pcscd}.
24055 @item @code{pcsc-lite} (default: @code{pcsc-lite})
24056 The pcsc-lite package that provides pcscd.
24057 @item @code{usb-drivers} (default: @code{(list ccid)})
24058 List of packages that provide USB drivers to pcscd. Drivers are expected to be
24059 under @file{pcsc/drivers} in the store directory of the package.
24064 @subsubheading Lirc Service
24066 The @code{(gnu services lirc)} module provides the following service.
24068 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
24069 [#:device #f] [#:driver #f] [#:config-file #f] @
24070 [#:extra-options '()]
24071 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
24072 decodes infrared signals from remote controls.
24074 Optionally, @var{device}, @var{driver} and @var{config-file}
24075 (configuration file name) may be specified. See @command{lircd} manual
24078 Finally, @var{extra-options} is a list of additional command-line options
24079 passed to @command{lircd}.
24083 @subsubheading Spice Service
24085 The @code{(gnu services spice)} module provides the following service.
24087 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
24088 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
24089 that enables sharing the clipboard with a vm and setting the guest display
24090 resolution when the graphical console window resizes.
24093 @cindex inputattach
24094 @subsubheading inputattach Service
24096 @cindex tablet input, for Xorg
24097 @cindex touchscreen input, for Xorg
24098 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
24099 use input devices such as Wacom tablets, touchscreens, or joysticks with the
24100 Xorg display server.
24102 @deffn {Scheme Variable} inputattach-service-type
24103 Type of a service that runs @command{inputattach} on a device and
24104 dispatches events from it.
24107 @deftp {Data Type} inputattach-configuration
24109 @item @code{device-type} (default: @code{"wacom"})
24110 The type of device to connect to. Run @command{inputattach --help}, from the
24111 @code{inputattach} package, to see the list of supported device types.
24113 @item @code{device} (default: @code{"/dev/ttyS0"})
24114 The device file to connect to the device.
24116 @item @code{log-file} (default: @code{#f})
24117 If true, this must be the name of a file to log messages to.
24121 @subsection Dictionary Services
24123 The @code{(gnu services dict)} module provides the following service:
24125 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
24126 Return a service that runs the @command{dicod} daemon, an implementation
24127 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
24129 The optional @var{config} argument specifies the configuration for
24130 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
24131 default it serves the GNU Collaborative International Dictonary of English.
24133 You can add @command{open localhost} to your @file{~/.dico} file to make
24134 @code{localhost} the default server for @command{dico} client
24135 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
24138 @deftp {Data Type} dicod-configuration
24139 Data type representing the configuration of dicod.
24142 @item @code{dico} (default: @var{dico})
24143 Package object of the GNU Dico dictionary server.
24145 @item @code{interfaces} (default: @var{'("localhost")})
24146 This is the list of IP addresses and ports and possibly socket file
24147 names to listen to (@pxref{Server Settings, @code{listen} directive,,
24148 dico, GNU Dico Manual}).
24150 @item @code{handlers} (default: @var{'()})
24151 List of @code{<dicod-handler>} objects denoting handlers (module instances).
24153 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
24154 List of @code{<dicod-database>} objects denoting dictionaries to be served.
24158 @deftp {Data Type} dicod-handler
24159 Data type representing a dictionary handler (module instance).
24163 Name of the handler (module instance).
24165 @item @code{module} (default: @var{#f})
24166 Name of the dicod module of the handler (instance). If it is @code{#f},
24167 the module has the same name as the handler.
24168 (@pxref{Modules,,, dico, GNU Dico Manual}).
24170 @item @code{options}
24171 List of strings or gexps representing the arguments for the module handler
24175 @deftp {Data Type} dicod-database
24176 Data type representing a dictionary database.
24180 Name of the database, will be used in DICT commands.
24182 @item @code{handler}
24183 Name of the dicod handler (module instance) used by this database
24184 (@pxref{Handlers,,, dico, GNU Dico Manual}).
24186 @item @code{complex?} (default: @var{#f})
24187 Whether the database configuration complex. The complex configuration
24188 will need a corresponding @code{<dicod-handler>} object, otherwise not.
24190 @item @code{options}
24191 List of strings or gexps representing the arguments for the database
24192 (@pxref{Databases,,, dico, GNU Dico Manual}).
24196 @defvr {Scheme Variable} %dicod-database:gcide
24197 A @code{<dicod-database>} object serving the GNU Collaborative International
24198 Dictionary of English using the @code{gcide} package.
24201 The following is an example @code{dicod-service} configuration.
24204 (dicod-service #:config
24205 (dicod-configuration
24206 (handlers (list (dicod-handler
24210 (list #~(string-append "dbdir=" #$wordnet))))))
24211 (databases (list (dicod-database
24214 (handler "wordnet")
24215 (options '("database=wn")))
24216 %dicod-database:gcide))))
24220 @subsubheading Docker Service
24222 The @code{(gnu services docker)} module provides the following services.
24224 @defvr {Scheme Variable} docker-service-type
24226 This is the type of the service that runs @url{https://www.docker.com,Docker},
24227 a daemon that can execute application bundles (sometimes referred to as
24228 ``containers'') in isolated environments.
24232 @deftp {Data Type} docker-configuration
24233 This is the data type representing the configuration of Docker and Containerd.
24237 @item @code{package} (default: @code{docker})
24238 The Docker package to use.
24240 @item @code{containerd} (default: @var{containerd})
24241 The Containerd package to use.
24247 @subsubheading Auditd Service
24249 The @code{(gnu services auditd)} module provides the following service.
24251 @defvr {Scheme Variable} auditd-service-type
24253 This is the type of the service that runs
24254 @url{https://people.redhat.com/sgrubb/audit/,auditd},
24255 a daemon that tracks security-relevant information on your system.
24257 Examples of things that can be tracked:
24267 Failed login attempts
24274 @command{auditctl} from the @code{audit} package can be used in order
24275 to add or remove events to be tracked (until the next reboot).
24276 In order to permanently track events, put the command line arguments
24277 of auditctl into @file{/etc/audit/audit.rules}.
24278 @command{aureport} from the @code{audit} package can be used in order
24279 to view a report of all recorded events.
24280 The audit daemon usually logs into the directory @file{/var/log/audit}.
24284 @deftp {Data Type} auditd-configuration
24285 This is the data type representing the configuration of auditd.
24289 @item @code{audit} (default: @code{audit})
24290 The audit package to use.
24295 @defvr {Scheme Variable} singularity-service-type
24296 This is the type of the service that allows you to run
24297 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
24298 create and run application bundles (aka. ``containers''). The value for this
24299 service is the Singularity package to use.
24301 The service does not install a daemon; instead, it installs helper programs as
24302 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
24303 @command{singularity run} and similar commands.
24307 @subsubheading Nix service
24309 The @code{(gnu services nix)} module provides the following service.
24311 @defvr {Scheme Variable} nix-service-type
24313 This is the type of the service that runs build daemon of the
24314 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
24318 (use-modules (gnu))
24319 (use-service-modules nix)
24320 (use-package-modules package-management)
24324 (packages (append (list nix)
24327 (services (append (list (service nix-service-type))
24331 After @command{guix system reconfigure} configure Nix for your user:
24334 @item Add a Nix channel and update it. See
24335 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
24337 @item Create a symlink to your profile and activate Nix profile:
24341 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
24342 $ source /run/current-system/profile/etc/profile.d/nix.sh
24347 @node Setuid Programs
24348 @section Setuid Programs
24350 @cindex setuid programs
24351 Some programs need to run with ``root'' privileges, even when they are
24352 launched by unprivileged users. A notorious example is the
24353 @command{passwd} program, which users can run to change their
24354 password, and which needs to access the @file{/etc/passwd} and
24355 @file{/etc/shadow} files---something normally restricted to root, for
24356 obvious security reasons. To address that, these executables are
24357 @dfn{setuid-root}, meaning that they always run with root privileges
24358 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
24359 for more info about the setuid mechanism.)
24361 The store itself @emph{cannot} contain setuid programs: that would be a
24362 security issue since any user on the system can write derivations that
24363 populate the store (@pxref{The Store}). Thus, a different mechanism is
24364 used: instead of changing the setuid bit directly on files that are in
24365 the store, we let the system administrator @emph{declare} which programs
24366 should be setuid root.
24368 The @code{setuid-programs} field of an @code{operating-system}
24369 declaration contains a list of G-expressions denoting the names of
24370 programs to be setuid-root (@pxref{Using the Configuration System}).
24371 For instance, the @command{passwd} program, which is part of the Shadow
24372 package, can be designated by this G-expression (@pxref{G-Expressions}):
24375 #~(string-append #$shadow "/bin/passwd")
24378 A default set of setuid programs is defined by the
24379 @code{%setuid-programs} variable of the @code{(gnu system)} module.
24381 @defvr {Scheme Variable} %setuid-programs
24382 A list of G-expressions denoting common programs that are setuid-root.
24384 The list includes commands such as @command{passwd}, @command{ping},
24385 @command{su}, and @command{sudo}.
24388 Under the hood, the actual setuid programs are created in the
24389 @file{/run/setuid-programs} directory at system activation time. The
24390 files in this directory refer to the ``real'' binaries, which are in the
24393 @node X.509 Certificates
24394 @section X.509 Certificates
24396 @cindex HTTPS, certificates
24397 @cindex X.509 certificates
24399 Web servers available over HTTPS (that is, HTTP over the transport-layer
24400 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
24401 that the client can then use to @emph{authenticate} the server. To do
24402 that, clients verify that the server's certificate is signed by a
24403 so-called @dfn{certificate authority} (CA). But to verify the CA's
24404 signature, clients must have first acquired the CA's certificate.
24406 Web browsers such as GNU@tie{}IceCat include their own set of CA
24407 certificates, such that they are able to verify CA signatures
24410 However, most other programs that can talk HTTPS---@command{wget},
24411 @command{git}, @command{w3m}, etc.---need to be told where CA
24412 certificates can be found.
24414 @cindex @code{nss-certs}
24415 In Guix, this is done by adding a package that provides certificates
24416 to the @code{packages} field of the @code{operating-system} declaration
24417 (@pxref{operating-system Reference}). Guix includes one such package,
24418 @code{nss-certs}, which is a set of CA certificates provided as part of
24419 Mozilla's Network Security Services.
24421 Note that it is @emph{not} part of @code{%base-packages}, so you need to
24422 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
24423 most applications and libraries look for certificates by default, points
24424 to the certificates installed globally.
24426 Unprivileged users, including users of Guix on a foreign distro,
24427 can also install their own certificate package in
24428 their profile. A number of environment variables need to be defined so
24429 that applications and libraries know where to find them. Namely, the
24430 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
24431 variables. Some applications add their own environment variables; for
24432 instance, the Git version control system honors the certificate bundle
24433 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
24434 would typically run something like:
24437 $ guix install nss-certs
24438 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
24439 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24440 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
24443 As another example, R requires the @code{CURL_CA_BUNDLE} environment
24444 variable to point to a certificate bundle, so you would have to run
24445 something like this:
24448 $ guix install nss-certs
24449 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24452 For other applications you may want to look up the required environment
24453 variable in the relevant documentation.
24456 @node Name Service Switch
24457 @section Name Service Switch
24459 @cindex name service switch
24461 The @code{(gnu system nss)} module provides bindings to the
24462 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
24463 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
24464 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
24465 extended with new ``name'' lookup methods for system databases, which
24466 includes host names, service names, user accounts, and more (@pxref{Name
24467 Service Switch, System Databases and Name Service Switch,, libc, The GNU
24468 C Library Reference Manual}).
24470 The NSS configuration specifies, for each system database, which lookup
24471 method is to be used, and how the various methods are chained
24472 together---for instance, under which circumstances NSS should try the
24473 next method in the list. The NSS configuration is given in the
24474 @code{name-service-switch} field of @code{operating-system} declarations
24475 (@pxref{operating-system Reference, @code{name-service-switch}}).
24478 @cindex .local, host name lookup
24479 As an example, the declaration below configures the NSS to use the
24480 @uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
24481 back-end}, which supports host name lookups over multicast DNS (mDNS)
24482 for host names ending in @code{.local}:
24485 (name-service-switch
24486 (hosts (list %files ;first, check /etc/hosts
24488 ;; If the above did not succeed, try
24489 ;; with 'mdns_minimal'.
24491 (name "mdns_minimal")
24493 ;; 'mdns_minimal' is authoritative for
24494 ;; '.local'. When it returns "not found",
24495 ;; no need to try the next methods.
24496 (reaction (lookup-specification
24497 (not-found => return))))
24499 ;; Then fall back to DNS.
24503 ;; Finally, try with the "full" 'mdns'.
24508 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
24509 contains this configuration, so you will not have to type it if all you
24510 want is to have @code{.local} host lookup working.
24512 Note that, in this case, in addition to setting the
24513 @code{name-service-switch} of the @code{operating-system} declaration,
24514 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
24515 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
24516 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
24517 to the name service cache daemon (@pxref{Base Services,
24518 @code{nscd-service}}).
24520 For convenience, the following variables provide typical NSS
24523 @defvr {Scheme Variable} %default-nss
24524 This is the default name service switch configuration, a
24525 @code{name-service-switch} object.
24528 @defvr {Scheme Variable} %mdns-host-lookup-nss
24529 This is the name service switch configuration with support for host name
24530 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
24533 The reference for name service switch configuration is given below. It
24534 is a direct mapping of the configuration file format of the C library , so
24535 please refer to the C library manual for more information (@pxref{NSS
24536 Configuration File,,, libc, The GNU C Library Reference Manual}).
24537 Compared to the configuration file format of libc NSS, it has the advantage
24538 not only of adding this warm parenthetic feel that we like, but also
24539 static checks: you will know about syntax errors and typos as soon as you
24540 run @command{guix system}.
24542 @deftp {Data Type} name-service-switch
24544 This is the data type representation the configuration of libc's name
24545 service switch (NSS). Each field below represents one of the supported
24562 The system databases handled by the NSS. Each of these fields must be a
24563 list of @code{<name-service>} objects (see below).
24567 @deftp {Data Type} name-service
24569 This is the data type representing an actual name service and the
24570 associated lookup action.
24574 A string denoting the name service (@pxref{Services in the NSS
24575 configuration,,, libc, The GNU C Library Reference Manual}).
24577 Note that name services listed here must be visible to nscd. This is
24578 achieved by passing the @code{#:name-services} argument to
24579 @code{nscd-service} the list of packages providing the needed name
24580 services (@pxref{Base Services, @code{nscd-service}}).
24583 An action specified using the @code{lookup-specification} macro
24584 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
24585 Reference Manual}). For example:
24588 (lookup-specification (unavailable => continue)
24589 (success => return))
24594 @node Initial RAM Disk
24595 @section Initial RAM Disk
24598 @cindex initial RAM disk
24599 For bootstrapping purposes, the Linux-Libre kernel is passed an
24600 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
24601 root file system as well as an initialization script. The latter is
24602 responsible for mounting the real root file system, and for loading any
24603 kernel modules that may be needed to achieve that.
24605 The @code{initrd-modules} field of an @code{operating-system}
24606 declaration allows you to specify Linux-libre kernel modules that must
24607 be available in the initrd. In particular, this is where you would list
24608 modules needed to actually drive the hard disk where your root partition
24609 is---although the default value of @code{initrd-modules} should cover
24610 most use cases. For example, assuming you need the @code{megaraid_sas}
24611 module in addition to the default modules to be able to access your root
24612 file system, you would write:
24617 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
24620 @defvr {Scheme Variable} %base-initrd-modules
24621 This is the list of kernel modules included in the initrd by default.
24624 Furthermore, if you need lower-level customization, the @code{initrd}
24625 field of an @code{operating-system} declaration allows
24626 you to specify which initrd you would like to use. The @code{(gnu
24627 system linux-initrd)} module provides three ways to build an initrd: the
24628 high-level @code{base-initrd} procedure and the low-level
24629 @code{raw-initrd} and @code{expression->initrd} procedures.
24631 The @code{base-initrd} procedure is intended to cover most common uses.
24632 For example, if you want to add a bunch of kernel modules to be loaded
24633 at boot time, you can define the @code{initrd} field of the operating
24634 system declaration like this:
24637 (initrd (lambda (file-systems . rest)
24638 ;; Create a standard initrd but set up networking
24639 ;; with the parameters QEMU expects by default.
24640 (apply base-initrd file-systems
24641 #:qemu-networking? #t
24645 The @code{base-initrd} procedure also handles common use cases that
24646 involves using the system as a QEMU guest, or as a ``live'' system with
24647 volatile root file system.
24649 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
24650 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
24651 such as trying to guess which kernel modules and packages should be included
24652 to the initrd. An example use of @code{raw-initrd} is when a user has
24653 a custom Linux kernel configuration and default kernel modules included by
24654 @code{base-initrd} are not available.
24656 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
24657 honors several options passed on the Linux kernel command line
24658 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
24659 @code{-append} option of QEMU), notably:
24662 @item --load=@var{boot}
24663 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
24664 program, once it has mounted the root file system.
24666 Guix uses this option to yield control to a boot program that runs the
24667 service activation programs and then spawns the GNU@tie{}Shepherd, the
24668 initialization system.
24670 @item --root=@var{root}
24671 Mount @var{root} as the root file system. @var{root} can be a
24672 device name like @code{/dev/sda1}, a file system label, or a file system
24675 @item --system=@var{system}
24676 Have @file{/run/booted-system} and @file{/run/current-system} point to
24679 @item modprobe.blacklist=@var{modules}@dots{}
24680 @cindex module, black-listing
24681 @cindex black list, of kernel modules
24682 Instruct the initial RAM disk as well as the @command{modprobe} command
24683 (from the kmod package) to refuse to load @var{modules}. @var{modules}
24684 must be a comma-separated list of module names---e.g.,
24685 @code{usbkbd,9pnet}.
24688 Start a read-eval-print loop (REPL) from the initial RAM disk before it
24689 tries to load kernel modules and to mount the root file system. Our
24690 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
24691 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
24692 Manual}, for more information on Guile's REPL.
24696 Now that you know all the features that initial RAM disks produced by
24697 @code{base-initrd} and @code{raw-initrd} provide,
24698 here is how to use it and customize it further.
24701 @cindex initial RAM disk
24702 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
24703 [#:linux-modules '()] [#:mapped-devices '()] @
24704 [#:keyboard-layout #f] @
24705 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
24706 Return a derivation that builds a raw initrd. @var{file-systems} is
24707 a list of file systems to be mounted by the initrd, possibly in addition to
24708 the root file system specified on the kernel command line via @code{--root}.
24709 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
24710 @var{mapped-devices} is a list of device mappings to realize before
24711 @var{file-systems} are mounted (@pxref{Mapped Devices}).
24712 @var{helper-packages} is a list of packages to be copied in the initrd. It may
24713 include @code{e2fsck/static} or other packages needed by the initrd to check
24714 the root file system.
24716 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24717 the desired console keyboard layout. This is done before @var{mapped-devices}
24718 are set up and before @var{file-systems} are mounted such that, should the
24719 user need to enter a passphrase or use the REPL, this happens using the
24720 intended keyboard layout.
24722 When @var{qemu-networking?} is true, set up networking with the standard QEMU
24723 parameters. When @var{virtio?} is true, load additional modules so that the
24724 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
24726 When @var{volatile-root?} is true, the root file system is writable but any changes
24730 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
24731 [#:mapped-devices '()] [#:keyboard-layout #f] @
24732 [#:qemu-networking? #f] [#:volatile-root? #f] @
24733 [#:linux-modules '()]
24734 Return as a file-like object a generic initrd, with kernel
24735 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
24736 mounted by the initrd, possibly in addition to the root file system specified
24737 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
24738 mappings to realize before @var{file-systems} are mounted.
24740 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24741 the desired console keyboard layout. This is done before @var{mapped-devices}
24742 are set up and before @var{file-systems} are mounted such that, should the
24743 user need to enter a passphrase or use the REPL, this happens using the
24744 intended keyboard layout.
24746 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
24748 The initrd is automatically populated with all the kernel modules necessary
24749 for @var{file-systems} and for the given options. Additional kernel
24750 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
24751 loaded at boot time in the order in which they appear.
24754 Needless to say, the initrds we produce and use embed a
24755 statically-linked Guile, and the initialization program is a Guile
24756 program. That gives a lot of flexibility. The
24757 @code{expression->initrd} procedure builds such an initrd, given the
24758 program to run in that initrd.
24760 @deffn {Scheme Procedure} expression->initrd @var{exp} @
24761 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
24762 Return as a file-like object a Linux initrd (a gzipped cpio archive)
24763 containing @var{guile} and that evaluates @var{exp}, a G-expression,
24764 upon booting. All the derivations referenced by @var{exp} are
24765 automatically copied to the initrd.
24768 @node Bootloader Configuration
24769 @section Bootloader Configuration
24772 @cindex boot loader
24774 The operating system supports multiple bootloaders. The bootloader is
24775 configured using @code{bootloader-configuration} declaration. All the
24776 fields of this structure are bootloader agnostic except for one field,
24777 @code{bootloader} that indicates the bootloader to be configured and
24780 Some of the bootloaders do not honor every field of
24781 @code{bootloader-configuration}. For instance, the extlinux
24782 bootloader does not support themes and thus ignores the @code{theme}
24785 @deftp {Data Type} bootloader-configuration
24786 The type of a bootloader configuration declaration.
24790 @item @code{bootloader}
24791 @cindex EFI, bootloader
24792 @cindex UEFI, bootloader
24793 @cindex BIOS, bootloader
24794 The bootloader to use, as a @code{bootloader} object. For now
24795 @code{grub-bootloader}, @code{grub-efi-bootloader},
24796 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
24798 @vindex grub-efi-bootloader
24799 @code{grub-efi-bootloader} allows to boot on modern systems using the
24800 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
24801 use if the installation image contains a @file{/sys/firmware/efi} directory
24802 when you boot it on your system.
24804 @vindex grub-bootloader
24805 @code{grub-bootloader} allows you to boot in particular Intel-based machines
24806 in ``legacy'' BIOS mode.
24808 @cindex ARM, bootloaders
24809 @cindex AArch64, bootloaders
24810 Available bootloaders are described in @code{(gnu bootloader @dots{})}
24811 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
24812 of bootloaders for a wide range of ARM and AArch64 systems, using the
24813 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
24815 @item @code{target}
24816 This is a string denoting the target onto which to install the
24819 The interpretation depends on the bootloader in question. For
24820 @code{grub-bootloader}, for example, it should be a device name understood by
24821 the bootloader @command{installer} command, such as @code{/dev/sda} or
24822 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
24823 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
24824 system, usually @file{/boot/efi}.
24826 @item @code{menu-entries} (default: @code{()})
24827 A possibly empty list of @code{menu-entry} objects (see below), denoting
24828 entries to appear in the bootloader menu, in addition to the current
24829 system entry and the entry pointing to previous system generations.
24831 @item @code{default-entry} (default: @code{0})
24832 The index of the default boot menu entry. Index 0 is for the entry of the
24835 @item @code{timeout} (default: @code{5})
24836 The number of seconds to wait for keyboard input before booting. Set to
24837 0 to boot immediately, and to -1 to wait indefinitely.
24839 @cindex keyboard layout, for the bootloader
24840 @item @code{keyboard-layout} (default: @code{#f})
24841 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
24842 layout, usually US@tie{}English (``qwerty'').
24844 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
24848 This option is currently ignored by bootloaders other than @code{grub} and
24852 @item @code{theme} (default: @var{#f})
24853 The bootloader theme object describing the theme to use. If no theme
24854 is provided, some bootloaders might use a default theme, that's true
24857 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
24858 The output terminals used for the bootloader boot menu, as a list of
24859 symbols. GRUB accepts the values: @code{console}, @code{serial},
24860 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
24861 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
24862 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
24863 configuration,,, grub,GNU GRUB manual}).
24865 @item @code{terminal-inputs} (default: @code{'()})
24866 The input terminals used for the bootloader boot menu, as a list of
24867 symbols. For GRUB, the default is the native platform terminal as
24868 determined at run-time. GRUB accepts the values: @code{console},
24869 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
24870 @code{usb_keyboard}. This field corresponds to the GRUB variable
24871 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
24874 @item @code{serial-unit} (default: @code{#f})
24875 The serial unit used by the bootloader, as an integer from 0 to 3.
24876 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
24877 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
24879 @item @code{serial-speed} (default: @code{#f})
24880 The speed of the serial interface, as an integer. For GRUB, the
24881 default value is chosen at run-time; currently GRUB chooses
24882 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
24889 Should you want to list additional boot menu entries @i{via} the
24890 @code{menu-entries} field above, you will need to create them with the
24891 @code{menu-entry} form. For example, imagine you want to be able to
24892 boot another distro (hard to imagine!), you can define a menu entry
24897 (label "The Other Distro")
24898 (linux "/boot/old/vmlinux-2.6.32")
24899 (linux-arguments '("root=/dev/sda2"))
24900 (initrd "/boot/old/initrd"))
24905 @deftp {Data Type} menu-entry
24906 The type of an entry in the bootloader menu.
24911 The label to show in the menu---e.g., @code{"GNU"}.
24914 The Linux kernel image to boot, for example:
24917 (file-append linux-libre "/bzImage")
24920 For GRUB, it is also possible to specify a device explicitly in the
24921 file path using GRUB's device naming convention (@pxref{Naming
24922 convention,,, grub, GNU GRUB manual}), for example:
24925 "(hd0,msdos1)/boot/vmlinuz"
24928 If the device is specified explicitly as above, then the @code{device}
24929 field is ignored entirely.
24931 @item @code{linux-arguments} (default: @code{()})
24932 The list of extra Linux kernel command-line arguments---e.g.,
24933 @code{("console=ttyS0")}.
24935 @item @code{initrd}
24936 A G-Expression or string denoting the file name of the initial RAM disk
24937 to use (@pxref{G-Expressions}).
24938 @item @code{device} (default: @code{#f})
24939 The device where the kernel and initrd are to be found---i.e., for GRUB,
24940 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
24942 This may be a file system label (a string), a file system UUID (a
24943 bytevector, @pxref{File Systems}), or @code{#f}, in which case
24944 the bootloader will search the device containing the file specified by
24945 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
24946 must @emph{not} be an OS device name such as @file{/dev/sda1}.
24951 @c FIXME: Write documentation once it's stable.
24952 For now only GRUB has theme support. GRUB themes are created using
24953 the @code{grub-theme} form, which is not documented yet.
24955 @defvr {Scheme Variable} %default-theme
24956 This is the default GRUB theme used by the operating system if no
24957 @code{theme} field is specified in @code{bootloader-configuration}
24960 It comes with a fancy background image displaying the GNU and Guix
24965 @node Invoking guix system
24966 @section Invoking @code{guix system}
24968 Once you have written an operating system declaration as seen in the
24969 previous section, it can be @dfn{instantiated} using the @command{guix
24970 system} command. The synopsis is:
24973 guix system @var{options}@dots{} @var{action} @var{file}
24976 @var{file} must be the name of a file containing an
24977 @code{operating-system} declaration. @var{action} specifies how the
24978 operating system is instantiated. Currently the following values are
24983 Display available service type definitions that match the given regular
24984 expressions, sorted by relevance:
24987 $ guix system search console font
24988 name: console-fonts
24989 location: gnu/services/base.scm:729:2
24990 extends: shepherd-root
24991 description: Install the given fonts on the specified ttys (fonts are
24992 + per virtual console on GNU/Linux). The value of this service is a list
24993 + of tty/font pairs like:
24995 + '(("tty1" . "LatGrkCyr-8x16"))
24999 location: gnu/services/base.scm:1048:2
25000 extends: shepherd-root
25001 description: Provide console login using the `mingetty' program.
25005 location: gnu/services/base.scm:775:2
25007 description: Provide a console log-in service as specified by its
25008 + configuration value, a `login-configuration' object.
25014 As for @command{guix package --search}, the result is written in
25015 @code{recutils} format, which makes it easy to filter the output
25016 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
25019 Build the operating system described in @var{file}, activate it, and
25020 switch to it@footnote{This action (and the related actions
25021 @code{switch-generation} and @code{roll-back}) are usable only on
25022 systems already running Guix System.}.
25024 This effects all the configuration specified in @var{file}: user
25025 accounts, system services, global package list, setuid programs, etc.
25026 The command starts system services specified in @var{file} that are not
25027 currently running; if a service is currently running this command will
25028 arrange for it to be upgraded the next time it is stopped (e.g.@: by
25029 @code{herd stop X} or @code{herd restart X}).
25031 This command creates a new generation whose number is one greater than
25032 the current generation (as reported by @command{guix system
25033 list-generations}). If that generation already exists, it will be
25034 overwritten. This behavior mirrors that of @command{guix package}
25035 (@pxref{Invoking guix package}).
25037 It also adds a bootloader menu entry for the new OS configuration,
25038 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
25039 entries for older configurations to a submenu, allowing you to choose
25040 an older system generation at boot time should you need it.
25043 @c The paragraph below refers to the problem discussed at
25044 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
25045 It is highly recommended to run @command{guix pull} once before you run
25046 @command{guix system reconfigure} for the first time (@pxref{Invoking
25047 guix pull}). Failing to do that you would see an older version of Guix
25048 once @command{reconfigure} has completed.
25051 @item switch-generation
25052 @cindex generations
25053 Switch to an existing system generation. This action atomically
25054 switches the system profile to the specified system generation. It
25055 also rearranges the system's existing bootloader menu entries. It
25056 makes the menu entry for the specified system generation the default,
25057 and it moves the entries for the other generatiors to a submenu, if
25058 supported by the bootloader being used. The next time the system
25059 boots, it will use the specified system generation.
25061 The bootloader itself is not being reinstalled when using this
25062 command. Thus, the installed bootloader is used with an updated
25063 configuration file.
25065 The target generation can be specified explicitly by its generation
25066 number. For example, the following invocation would switch to system
25070 guix system switch-generation 7
25073 The target generation can also be specified relative to the current
25074 generation with the form @code{+N} or @code{-N}, where @code{+3} means
25075 ``3 generations ahead of the current generation,'' and @code{-1} means
25076 ``1 generation prior to the current generation.'' When specifying a
25077 negative value such as @code{-1}, you must precede it with @code{--} to
25078 prevent it from being parsed as an option. For example:
25081 guix system switch-generation -- -1
25084 Currently, the effect of invoking this action is @emph{only} to switch
25085 the system profile to an existing generation and rearrange the
25086 bootloader menu entries. To actually start using the target system
25087 generation, you must reboot after running this action. In the future,
25088 it will be updated to do the same things as @command{reconfigure},
25089 like activating and deactivating services.
25091 This action will fail if the specified generation does not exist.
25094 @cindex rolling back
25095 Switch to the preceding system generation. The next time the system
25096 boots, it will use the preceding system generation. This is the inverse
25097 of @command{reconfigure}, and it is exactly the same as invoking
25098 @command{switch-generation} with an argument of @code{-1}.
25100 Currently, as with @command{switch-generation}, you must reboot after
25101 running this action to actually start using the preceding system
25104 @item delete-generations
25105 @cindex deleting system generations
25106 @cindex saving space
25107 Delete system generations, making them candidates for garbage collection
25108 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
25111 This works in the same way as @command{guix package --delete-generations}
25112 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
25113 arguments, all system generations but the current one are deleted:
25116 guix system delete-generations
25119 You can also select the generations you want to delete. The example below
25120 deletes all the system generations that are more than two month old:
25123 guix system delete-generations 2m
25126 Running this command automatically reinstalls the bootloader with an updated
25127 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
25128 longer lists the generations that have been deleted.
25131 Build the derivation of the operating system, which includes all the
25132 configuration files and programs needed to boot and run the system.
25133 This action does not actually install anything.
25136 Populate the given directory with all the files necessary to run the
25137 operating system specified in @var{file}. This is useful for first-time
25138 installations of Guix System. For instance:
25141 guix system init my-os-config.scm /mnt
25144 copies to @file{/mnt} all the store items required by the configuration
25145 specified in @file{my-os-config.scm}. This includes configuration
25146 files, packages, and so on. It also creates other essential files
25147 needed for the system to operate correctly---e.g., the @file{/etc},
25148 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
25150 This command also installs bootloader on the target specified in
25151 @file{my-os-config}, unless the @option{--no-bootloader} option was
25155 @cindex virtual machine
25157 @anchor{guix system vm}
25158 Build a virtual machine that contains the operating system declared in
25159 @var{file}, and return a script to run that virtual machine (VM).
25162 The @code{vm} action and others below
25163 can use KVM support in the Linux-libre kernel. Specifically, if the
25164 machine has hardware virtualization support, the corresponding
25165 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
25166 must exist and be readable and writable by the user and by the
25167 build users of the daemon (@pxref{Build Environment Setup}).
25170 Arguments given to the script are passed to QEMU as in the example
25171 below, which enables networking and requests 1@tie{}GiB of RAM for the
25175 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -net user
25178 The VM shares its store with the host system.
25180 Additional file systems can be shared between the host and the VM using
25181 the @code{--share} and @code{--expose} command-line options: the former
25182 specifies a directory to be shared with write access, while the latter
25183 provides read-only access to the shared directory.
25185 The example below creates a VM in which the user's home directory is
25186 accessible read-only, and where the @file{/exchange} directory is a
25187 read-write mapping of @file{$HOME/tmp} on the host:
25190 guix system vm my-config.scm \
25191 --expose=$HOME --share=$HOME/tmp=/exchange
25194 On GNU/Linux, the default is to boot directly to the kernel; this has
25195 the advantage of requiring only a very tiny root disk image since the
25196 store of the host can then be mounted.
25198 The @code{--full-boot} option forces a complete boot sequence, starting
25199 with the bootloader. This requires more disk space since a root image
25200 containing at least the kernel, initrd, and bootloader data files must
25201 be created. The @code{--image-size} option can be used to specify the
25204 @cindex System images, creation in various formats
25205 @cindex Creating system images in various formats
25208 @itemx docker-image
25209 Return a virtual machine, disk image, or Docker image of the operating
25210 system declared in @var{file} that stands alone. By default,
25211 @command{guix system} estimates the size of the image needed to store
25212 the system, but you can use the @option{--image-size} option to specify
25213 a value. Docker images are built to contain exactly what they need, so
25214 the @option{--image-size} option is ignored in the case of
25215 @code{docker-image}.
25217 You can specify the root file system type by using the
25218 @option{--file-system-type} option. It defaults to @code{ext4}.
25220 When using @code{vm-image}, the returned image is in qcow2 format, which
25221 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
25222 for more information on how to run the image in a virtual machine.
25224 When using @code{disk-image}, a raw disk image is produced; it can be
25225 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
25226 the device corresponding to a USB stick, one can copy the image to it
25227 using the following command:
25230 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
25233 When using @code{docker-image}, a Docker image is produced. Guix builds
25234 the image from scratch, not from a pre-existing Docker base image. As a
25235 result, it contains @emph{exactly} what you define in the operating
25236 system configuration file. You can then load the image and launch a
25237 Docker container using commands like the following:
25240 image_id="`docker load < guix-system-docker-image.tar.gz`"
25241 container_id="`docker create $image_id`"
25242 docker start $container_id
25245 This command starts a new Docker container from the specified image. It
25246 will boot the Guix system in the usual manner, which means it will
25247 start any services you have defined in the operating system
25248 configuration. You can get an interactive shell running in the container
25249 using @command{docker exec}:
25252 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
25255 Depending on what you run in the Docker container, it
25256 may be necessary to give the container additional permissions. For
25257 example, if you intend to build software using Guix inside of the Docker
25258 container, you may need to pass the @option{--privileged} option to
25259 @code{docker create}.
25262 Return a script to run the operating system declared in @var{file}
25263 within a container. Containers are a set of lightweight isolation
25264 mechanisms provided by the kernel Linux-libre. Containers are
25265 substantially less resource-demanding than full virtual machines since
25266 the kernel, shared objects, and other resources can be shared with the
25267 host system; this also means they provide thinner isolation.
25269 Currently, the script must be run as root in order to support more than
25270 a single user and group. The container shares its store with the host
25273 As with the @code{vm} action (@pxref{guix system vm}), additional file
25274 systems to be shared between the host and container can be specified
25275 using the @option{--share} and @option{--expose} options:
25278 guix system container my-config.scm \
25279 --expose=$HOME --share=$HOME/tmp=/exchange
25283 This option requires Linux-libre 3.19 or newer.
25288 @var{options} can contain any of the common build options (@pxref{Common
25289 Build Options}). In addition, @var{options} can contain one of the
25293 @item --expression=@var{expr}
25294 @itemx -e @var{expr}
25295 Consider the operating-system @var{expr} evaluates to.
25296 This is an alternative to specifying a file which evaluates to an
25298 This is used to generate the Guix system installer @pxref{Building the
25299 Installation Image}).
25301 @item --system=@var{system}
25302 @itemx -s @var{system}
25303 Attempt to build for @var{system} instead of the host system type.
25304 This works as per @command{guix build} (@pxref{Invoking guix build}).
25308 Return the derivation file name of the given operating system without
25311 @item --file-system-type=@var{type}
25312 @itemx -t @var{type}
25313 For the @code{disk-image} action, create a file system of the given
25314 @var{type} on the image.
25316 When this option is omitted, @command{guix system} uses @code{ext4}.
25318 @cindex ISO-9660 format
25319 @cindex CD image format
25320 @cindex DVD image format
25321 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
25322 for burning on CDs and DVDs.
25324 @item --image-size=@var{size}
25325 For the @code{vm-image} and @code{disk-image} actions, create an image
25326 of the given @var{size}. @var{size} may be a number of bytes, or it may
25327 include a unit as a suffix (@pxref{Block size, size specifications,,
25328 coreutils, GNU Coreutils}).
25330 When this option is omitted, @command{guix system} computes an estimate
25331 of the image size as a function of the size of the system declared in
25336 For the @code{container} action, allow containers to access the host network,
25337 that is, do not create a network namespace.
25339 @item --root=@var{file}
25340 @itemx -r @var{file}
25341 Make @var{file} a symlink to the result, and register it as a garbage
25344 @item --skip-checks
25345 Skip pre-installation safety checks.
25347 By default, @command{guix system init} and @command{guix system
25348 reconfigure} perform safety checks: they make sure the file systems that
25349 appear in the @code{operating-system} declaration actually exist
25350 (@pxref{File Systems}), and that any Linux kernel modules that may be
25351 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
25352 RAM Disk}). Passing this option skips these tests altogether.
25355 @cindex on-error strategy
25356 @cindex error strategy
25357 @item --on-error=@var{strategy}
25358 Apply @var{strategy} when an error occurs when reading @var{file}.
25359 @var{strategy} may be one of the following:
25362 @item nothing-special
25363 Report the error concisely and exit. This is the default strategy.
25366 Likewise, but also display a backtrace.
25369 Report the error and enter Guile's debugger. From there, you can run
25370 commands such as @code{,bt} to get a backtrace, @code{,locals} to
25371 display local variable values, and more generally inspect the state of the
25372 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
25373 a list of available debugging commands.
25377 Once you have built, configured, re-configured, and re-re-configured
25378 your Guix installation, you may find it useful to list the operating
25379 system generations available on disk---and that you can choose from the
25380 bootloader boot menu:
25384 @item list-generations
25385 List a summary of each generation of the operating system available on
25386 disk, in a human-readable way. This is similar to the
25387 @option{--list-generations} option of @command{guix package}
25388 (@pxref{Invoking guix package}).
25390 Optionally, one can specify a pattern, with the same syntax that is used
25391 in @command{guix package --list-generations}, to restrict the list of
25392 generations displayed. For instance, the following command displays
25393 generations that are up to 10 days old:
25396 $ guix system list-generations 10d
25401 The @command{guix system} command has even more to offer! The following
25402 sub-commands allow you to visualize how your system services relate to
25405 @anchor{system-extension-graph}
25408 @item extension-graph
25409 Emit in Dot/Graphviz format to standard output the @dfn{service
25410 extension graph} of the operating system defined in @var{file}
25411 (@pxref{Service Composition}, for more information on service
25417 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
25420 produces a PDF file showing the extension relations among services.
25422 @anchor{system-shepherd-graph}
25423 @item shepherd-graph
25424 Emit in Dot/Graphviz format to standard output the @dfn{dependency
25425 graph} of shepherd services of the operating system defined in
25426 @var{file}. @xref{Shepherd Services}, for more information and for an
25431 @node Invoking guix deploy
25432 @section Invoking @code{guix deploy}
25434 We've already seen @code{operating-system} declarations used to manage a
25435 machine's configuration locally. Suppose you need to configure multiple
25436 machines, though---perhaps you're managing a service on the web that's
25437 comprised of several servers. @command{guix deploy} enables you to use those
25438 same @code{operating-system} declarations to manage multiple remote hosts at
25439 once as a logical ``deployment''.
25442 The functionality described in this section is still under development
25443 and is subject to change. Get in touch with us on
25444 @email{guix-devel@@gnu.org}!
25448 guix deploy @var{file}
25451 Such an invocation will deploy the machines that the code within @var{file}
25452 evaluates to. As an example, @var{file} might contain a definition like this:
25455 ;; This is a Guix deployment of a "bare bones" setup, with
25456 ;; no X11 display server, to a machine with an SSH daemon
25457 ;; listening on localhost:2222. A configuration such as this
25458 ;; may be appropriate for virtual machine with ports
25459 ;; forwarded to the host's loopback interface.
25461 (use-service-modules networking ssh)
25462 (use-package-modules bootloaders)
25466 (host-name "gnu-deployed")
25467 (timezone "Etc/UTC")
25468 (bootloader (bootloader-configuration
25469 (bootloader grub-bootloader)
25470 (target "/dev/vda")
25471 (terminal-outputs '(console))))
25472 (file-systems (cons (file-system
25474 (device "/dev/vda1")
25476 %base-file-systems))
25478 (append (list (service dhcp-client-service-type)
25479 (service openssh-service-type
25480 (openssh-configuration
25481 (permit-root-login #t)
25482 (allow-empty-passwords? #t))))
25487 (environment managed-host-environment-type)
25488 (configuration (machine-ssh-configuration
25489 (host-name "localhost")
25490 (identity "./id_rsa")
25494 The file should evaluate to a list of @var{machine} objects. This example,
25495 upon being deployed, will create a new generation on the remote system
25496 realizing the @code{operating-system} declaration @var{%system}.
25497 @var{environment} and @var{configuration} specify how the machine should be
25498 provisioned---that is, how the computing resources should be created and
25499 managed. The above example does not create any resources, as a
25500 @code{'managed-host} is a machine that is already running the Guix system and
25501 available over the network. This is a particularly simple case; a more
25502 complex deployment may involve, for example, starting virtual machines through
25503 a Virtual Private Server (VPS) provider. In such a case, a different
25504 @var{environment} type would be used.
25506 @deftp {Data Type} machine
25507 This is the data type representing a single machine in a heterogeneous Guix
25511 @item @code{system}
25512 The object of the operating system configuration to deploy.
25514 @item @code{environment}
25515 An @code{environment-type} describing how the machine should be provisioned.
25516 At the moment, the only supported value is
25517 @code{managed-host-environment-type}.
25519 @item @code{configuration} (default: @code{#f})
25520 An object describing the configuration for the machine's @code{environment}.
25521 If the @code{environment} has a default configuration, @code{#f} maybe used.
25522 If @code{#f} is used for an environment with no default configuration,
25523 however, an error will be thrown.
25527 @deftp {Data Type} machine-ssh-configuration
25528 This is the data type representing the SSH client parameters for a machine
25529 with an @code{environment} of @code{managed-host-environment-type}.
25532 @item @code{host-name}
25533 @item @code{port} (default: @code{22})
25534 @item @code{user} (default: @code{"root"})
25535 @item @code{identity} (default: @code{#f})
25536 If specified, the path to the SSH private key to use to authenticate with the
25541 @node Running Guix in a VM
25542 @section Running Guix in a Virtual Machine
25544 @cindex virtual machine
25545 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
25547 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
25548 This image is a compressed image in QCOW format. You will first need to
25549 decompress with @command{xz -d}, and then you can pass it to an emulator such
25550 as QEMU (see below for details).
25552 This image boots the Xfce graphical environment and it contains some
25553 commonly-used tools. You can install more software in the image by running
25554 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
25555 also reconfigure the system based on its initial configuration file available
25556 as @file{/etc/config.scm} (@pxref{Using the Configuration System}).
25558 Instead of using this pre-built image, one can also build their own virtual
25559 machine image using @command{guix system vm-image} (@pxref{Invoking guix
25560 system}). The returned image is in qcow2 format, which the
25561 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
25564 If you built your own image, you must copy it out of the store
25565 (@pxref{The Store}) and give yourself permission to write to the copy
25566 before you can use it. When invoking QEMU, you must choose a system
25567 emulator that is suitable for your hardware platform. Here is a minimal
25568 QEMU invocation that will boot the result of @command{guix system
25569 vm-image} on x86_64 hardware:
25572 $ qemu-system-x86_64 \
25573 -net user -net nic,model=virtio \
25574 -enable-kvm -m 1024 \
25575 -device virtio-blk,drive=myhd \
25576 -drive if=none,file=/tmp/qemu-image,id=myhd
25579 Here is what each of these options means:
25582 @item qemu-system-x86_64
25583 This specifies the hardware platform to emulate. This should match the
25587 Enable the unprivileged user-mode network stack. The guest OS can
25588 access the host but not vice versa. This is the simplest way to get the
25591 @item -net nic,model=virtio
25592 You must create a network interface of a given model. If you do not
25593 create a NIC, the boot will fail. Assuming your hardware platform is
25594 x86_64, you can get a list of available NIC models by running
25595 @command{qemu-system-x86_64 -net nic,model=help}.
25598 If your system has hardware virtualization extensions, enabling the
25599 virtual machine support (KVM) of the Linux kernel will make things run
25602 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
25604 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
25605 which may be insufficient for some operations.
25607 @item -device virtio-blk,drive=myhd
25608 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
25609 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
25610 better performance than if it were emulating a complete disk drive. See the
25611 QEMU and KVM documentation for more info.
25613 @item -drive if=none,file=/tmp/qemu-image,id=myhd
25614 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
25615 the ``myhd'' drive.
25618 The default @command{run-vm.sh} script that is returned by an invocation of
25619 @command{guix system vm} does not add a @command{-net user} flag by default.
25620 To get network access from within the vm add the @code{(dhcp-client-service)}
25621 to your system definition and start the VM using
25622 @command{`guix system vm config.scm` -net user}. An important caveat of using
25623 @command{-net user} for networking is that @command{ping} will not work, because
25624 it uses the ICMP protocol. You'll have to use a different command to check for
25625 network connectivity, for example @command{guix download}.
25627 @subsection Connecting Through SSH
25631 To enable SSH inside a VM you need to add an SSH server like
25632 @code{openssh-service-type} to your VM (@pxref{Networking Services,
25633 @code{openssh-service-type}}). In addition you need to forward the SSH port,
25634 22 by default, to the host. You can do this with
25637 `guix system vm config.scm` -net user,hostfwd=tcp::10022-:22
25640 To connect to the VM you can run
25643 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
25646 The @command{-p} tells @command{ssh} the port you want to connect to.
25647 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
25648 every time you modify your @command{config.scm} file and the
25649 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
25650 connection to an unknown host every time you connect.
25652 @subsection Using @command{virt-viewer} with Spice
25654 As an alternative to the default @command{qemu} graphical client you can
25655 use the @command{remote-viewer} from the @command{virt-viewer} package. To
25656 connect pass the @command{-spice port=5930,disable-ticketing} flag to
25657 @command{qemu}. See previous section for further information on how to do this.
25659 Spice also allows you to do some nice stuff like share your clipboard with your
25660 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
25663 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
25664 -chardev spicevmc,name=vdagent,id=vdagent
25665 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
25666 name=com.redhat.spice.0
25669 You'll also need to add the @pxref{Miscellaneous Services, Spice service}.
25671 @node Defining Services
25672 @section Defining Services
25674 The previous sections show the available services and how one can combine
25675 them in an @code{operating-system} declaration. But how do we define
25676 them in the first place? And what is a service anyway?
25679 * Service Composition:: The model for composing services.
25680 * Service Types and Services:: Types and services.
25681 * Service Reference:: API reference.
25682 * Shepherd Services:: A particular type of service.
25685 @node Service Composition
25686 @subsection Service Composition
25690 Here we define a @dfn{service} as, broadly, something that extends the
25691 functionality of the operating system. Often a service is a process---a
25692 @dfn{daemon}---started when the system boots: a secure shell server, a
25693 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
25694 whose execution can be triggered by another daemon---e.g., an FTP server
25695 started by @command{inetd} or a D-Bus service activated by
25696 @command{dbus-daemon}. Occasionally, a service does not map to a
25697 daemon. For instance, the ``account'' service collects user accounts
25698 and makes sure they exist when the system runs; the ``udev'' service
25699 collects device management rules and makes them available to the eudev
25700 daemon; the @file{/etc} service populates the @file{/etc} directory
25703 @cindex service extensions
25704 Guix system services are connected by @dfn{extensions}. For instance, the
25705 secure shell service @emph{extends} the Shepherd---the
25706 initialization system, running as PID@tie{}1---by giving it the command
25707 lines to start and stop the secure shell daemon (@pxref{Networking
25708 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
25709 service by passing it its @file{.service} specification, and extends the
25710 udev service by passing it device management rules (@pxref{Desktop
25711 Services, @code{upower-service}}); the Guix daemon service extends the
25712 Shepherd by passing it the command lines to start and stop the daemon,
25713 and extends the account service by passing it a list of required build
25714 user accounts (@pxref{Base Services}).
25716 All in all, services and their ``extends'' relations form a directed
25717 acyclic graph (DAG). If we represent services as boxes and extensions
25718 as arrows, a typical system might provide something like this:
25720 @image{images/service-graph,,5in,Typical service extension graph.}
25722 @cindex system service
25723 At the bottom, we see the @dfn{system service}, which produces the
25724 directory containing everything to run and boot the system, as returned
25725 by the @command{guix system build} command. @xref{Service Reference},
25726 to learn about the other service types shown here.
25727 @xref{system-extension-graph, the @command{guix system extension-graph}
25728 command}, for information on how to generate this representation for a
25729 particular operating system definition.
25731 @cindex service types
25732 Technically, developers can define @dfn{service types} to express these
25733 relations. There can be any number of services of a given type on the
25734 system---for instance, a system running two instances of the GNU secure
25735 shell server (lsh) has two instances of @code{lsh-service-type}, with
25736 different parameters.
25738 The following section describes the programming interface for service
25739 types and services.
25741 @node Service Types and Services
25742 @subsection Service Types and Services
25744 A @dfn{service type} is a node in the DAG described above. Let us start
25745 with a simple example, the service type for the Guix build daemon
25746 (@pxref{Invoking guix-daemon}):
25749 (define guix-service-type
25753 (list (service-extension shepherd-root-service-type guix-shepherd-service)
25754 (service-extension account-service-type guix-accounts)
25755 (service-extension activation-service-type guix-activation)))
25756 (default-value (guix-configuration))))
25760 It defines three things:
25764 A name, whose sole purpose is to make inspection and debugging easier.
25767 A list of @dfn{service extensions}, where each extension designates the
25768 target service type and a procedure that, given the parameters of the
25769 service, returns a list of objects to extend the service of that type.
25771 Every service type has at least one service extension. The only
25772 exception is the @dfn{boot service type}, which is the ultimate service.
25775 Optionally, a default value for instances of this type.
25778 In this example, @code{guix-service-type} extends three services:
25781 @item shepherd-root-service-type
25782 The @code{guix-shepherd-service} procedure defines how the Shepherd
25783 service is extended. Namely, it returns a @code{<shepherd-service>}
25784 object that defines how @command{guix-daemon} is started and stopped
25785 (@pxref{Shepherd Services}).
25787 @item account-service-type
25788 This extension for this service is computed by @code{guix-accounts},
25789 which returns a list of @code{user-group} and @code{user-account}
25790 objects representing the build user accounts (@pxref{Invoking
25793 @item activation-service-type
25794 Here @code{guix-activation} is a procedure that returns a gexp, which is
25795 a code snippet to run at ``activation time''---e.g., when the service is
25799 A service of this type is instantiated like this:
25802 (service guix-service-type
25803 (guix-configuration
25805 (use-substitutes? #f)))
25808 The second argument to the @code{service} form is a value representing
25809 the parameters of this specific service instance.
25810 @xref{guix-configuration-type, @code{guix-configuration}}, for
25811 information about the @code{guix-configuration} data type. When the
25812 value is omitted, the default value specified by
25813 @code{guix-service-type} is used:
25816 (service guix-service-type)
25819 @code{guix-service-type} is quite simple because it extends other
25820 services but is not extensible itself.
25822 @c @subsubsubsection Extensible Service Types
25824 The service type for an @emph{extensible} service looks like this:
25827 (define udev-service-type
25828 (service-type (name 'udev)
25830 (list (service-extension shepherd-root-service-type
25831 udev-shepherd-service)))
25833 (compose concatenate) ;concatenate the list of rules
25834 (extend (lambda (config rules)
25836 (($ <udev-configuration> udev initial-rules)
25837 (udev-configuration
25838 (udev udev) ;the udev package to use
25839 (rules (append initial-rules rules)))))))))
25842 This is the service type for the
25843 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
25844 management daemon}. Compared to the previous example, in addition to an
25845 extension of @code{shepherd-root-service-type}, we see two new fields:
25849 This is the procedure to @dfn{compose} the list of extensions to
25850 services of this type.
25852 Services can extend the udev service by passing it lists of rules; we
25853 compose those extensions simply by concatenating them.
25856 This procedure defines how the value of the service is @dfn{extended} with
25857 the composition of the extensions.
25859 Udev extensions are composed into a list of rules, but the udev service
25860 value is itself a @code{<udev-configuration>} record. So here, we
25861 extend that record by appending the list of rules it contains to the
25862 list of contributed rules.
25865 This is a string giving an overview of the service type. The string can
25866 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
25867 @command{guix system search} command searches these strings and displays
25868 them (@pxref{Invoking guix system}).
25871 There can be only one instance of an extensible service type such as
25872 @code{udev-service-type}. If there were more, the
25873 @code{service-extension} specifications would be ambiguous.
25875 Still here? The next section provides a reference of the programming
25876 interface for services.
25878 @node Service Reference
25879 @subsection Service Reference
25881 We have seen an overview of service types (@pxref{Service Types and
25882 Services}). This section provides a reference on how to manipulate
25883 services and service types. This interface is provided by the
25884 @code{(gnu services)} module.
25886 @deffn {Scheme Procedure} service @var{type} [@var{value}]
25887 Return a new service of @var{type}, a @code{<service-type>} object (see
25888 below.) @var{value} can be any object; it represents the parameters of
25889 this particular service instance.
25891 When @var{value} is omitted, the default value specified by @var{type}
25892 is used; if @var{type} does not specify a default value, an error is
25895 For instance, this:
25898 (service openssh-service-type)
25902 is equivalent to this:
25905 (service openssh-service-type
25906 (openssh-configuration))
25909 In both cases the result is an instance of @code{openssh-service-type}
25910 with the default configuration.
25913 @deffn {Scheme Procedure} service? @var{obj}
25914 Return true if @var{obj} is a service.
25917 @deffn {Scheme Procedure} service-kind @var{service}
25918 Return the type of @var{service}---i.e., a @code{<service-type>} object.
25921 @deffn {Scheme Procedure} service-value @var{service}
25922 Return the value associated with @var{service}. It represents its
25926 Here is an example of how a service is created and manipulated:
25930 (service nginx-service-type
25931 (nginx-configuration
25933 (log-directory log-directory)
25934 (run-directory run-directory)
25935 (file config-file))))
25940 (eq? (service-kind s) nginx-service-type)
25944 The @code{modify-services} form provides a handy way to change the
25945 parameters of some of the services of a list such as
25946 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
25947 evaluates to a list of services. Of course, you could always use
25948 standard list combinators such as @code{map} and @code{fold} to do that
25949 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
25950 @code{modify-services} simply provides a more concise form for this
25953 @deffn {Scheme Syntax} modify-services @var{services} @
25954 (@var{type} @var{variable} => @var{body}) @dots{}
25956 Modify the services listed in @var{services} according to the given
25957 clauses. Each clause has the form:
25960 (@var{type} @var{variable} => @var{body})
25963 where @var{type} is a service type---e.g.,
25964 @code{guix-service-type}---and @var{variable} is an identifier that is
25965 bound within the @var{body} to the service parameters---e.g., a
25966 @code{guix-configuration} instance---of the original service of that
25969 The @var{body} should evaluate to the new service parameters, which will
25970 be used to configure the new service. This new service will replace the
25971 original in the resulting list. Because a service's service parameters
25972 are created using @code{define-record-type*}, you can write a succinct
25973 @var{body} that evaluates to the new service parameters by using the
25974 @code{inherit} feature that @code{define-record-type*} provides.
25976 @xref{Using the Configuration System}, for example usage.
25980 Next comes the programming interface for service types. This is
25981 something you want to know when writing new service definitions, but not
25982 necessarily when simply looking for ways to customize your
25983 @code{operating-system} declaration.
25985 @deftp {Data Type} service-type
25986 @cindex service type
25987 This is the representation of a @dfn{service type} (@pxref{Service Types
25992 This is a symbol, used only to simplify inspection and debugging.
25994 @item @code{extensions}
25995 A non-empty list of @code{<service-extension>} objects (see below).
25997 @item @code{compose} (default: @code{#f})
25998 If this is @code{#f}, then the service type denotes services that cannot
25999 be extended---i.e., services that do not receive ``values'' from other
26002 Otherwise, it must be a one-argument procedure. The procedure is called
26003 by @code{fold-services} and is passed a list of values collected from
26004 extensions. It may return any single value.
26006 @item @code{extend} (default: @code{#f})
26007 If this is @code{#f}, services of this type cannot be extended.
26009 Otherwise, it must be a two-argument procedure: @code{fold-services}
26010 calls it, passing it the initial value of the service as the first
26011 argument and the result of applying @code{compose} to the extension
26012 values as the second argument. It must return a value that is a valid
26013 parameter value for the service instance.
26016 @xref{Service Types and Services}, for examples.
26019 @deffn {Scheme Procedure} service-extension @var{target-type} @
26021 Return a new extension for services of type @var{target-type}.
26022 @var{compute} must be a one-argument procedure: @code{fold-services}
26023 calls it, passing it the value associated with the service that provides
26024 the extension; it must return a valid value for the target service.
26027 @deffn {Scheme Procedure} service-extension? @var{obj}
26028 Return true if @var{obj} is a service extension.
26031 Occasionally, you might want to simply extend an existing service. This
26032 involves creating a new service type and specifying the extension of
26033 interest, which can be verbose; the @code{simple-service} procedure
26034 provides a shorthand for this.
26036 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
26037 Return a service that extends @var{target} with @var{value}. This works
26038 by creating a singleton service type @var{name}, of which the returned
26039 service is an instance.
26041 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
26045 (simple-service 'my-mcron-job mcron-service-type
26046 #~(job '(next-hour (3)) "guix gc -F 2G"))
26050 At the core of the service abstraction lies the @code{fold-services}
26051 procedure, which is responsible for ``compiling'' a list of services
26052 down to a single directory that contains everything needed to boot and
26053 run the system---the directory shown by the @command{guix system build}
26054 command (@pxref{Invoking guix system}). In essence, it propagates
26055 service extensions down the service graph, updating each node parameters
26056 on the way, until it reaches the root node.
26058 @deffn {Scheme Procedure} fold-services @var{services} @
26059 [#:target-type @var{system-service-type}]
26060 Fold @var{services} by propagating their extensions down to the root of
26061 type @var{target-type}; return the root service adjusted accordingly.
26064 Lastly, the @code{(gnu services)} module also defines several essential
26065 service types, some of which are listed below.
26067 @defvr {Scheme Variable} system-service-type
26068 This is the root of the service graph. It produces the system directory
26069 as returned by the @command{guix system build} command.
26072 @defvr {Scheme Variable} boot-service-type
26073 The type of the ``boot service'', which produces the @dfn{boot script}.
26074 The boot script is what the initial RAM disk runs when booting.
26077 @defvr {Scheme Variable} etc-service-type
26078 The type of the @file{/etc} service. This service is used to create
26079 files under @file{/etc} and can be extended by
26080 passing it name/file tuples such as:
26083 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
26086 In this example, the effect would be to add an @file{/etc/issue} file
26087 pointing to the given file.
26090 @defvr {Scheme Variable} setuid-program-service-type
26091 Type for the ``setuid-program service''. This service collects lists of
26092 executable file names, passed as gexps, and adds them to the set of
26093 setuid-root programs on the system (@pxref{Setuid Programs}).
26096 @defvr {Scheme Variable} profile-service-type
26097 Type of the service that populates the @dfn{system profile}---i.e., the
26098 programs under @file{/run/current-system/profile}. Other services can
26099 extend it by passing it lists of packages to add to the system profile.
26103 @node Shepherd Services
26104 @subsection Shepherd Services
26106 @cindex shepherd services
26108 @cindex init system
26109 The @code{(gnu services shepherd)} module provides a way to define
26110 services managed by the GNU@tie{}Shepherd, which is the
26111 initialization system---the first process that is started when the
26112 system boots, also known as PID@tie{}1
26113 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
26115 Services in the Shepherd can depend on each other. For instance, the
26116 SSH daemon may need to be started after the syslog daemon has been
26117 started, which in turn can only happen once all the file systems have
26118 been mounted. The simple operating system defined earlier (@pxref{Using
26119 the Configuration System}) results in a service graph like this:
26121 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
26123 You can actually generate such a graph for any operating system
26124 definition using the @command{guix system shepherd-graph} command
26125 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
26127 The @code{%shepherd-root-service} is a service object representing
26128 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
26129 by passing it lists of @code{<shepherd-service>} objects.
26131 @deftp {Data Type} shepherd-service
26132 The data type representing a service managed by the Shepherd.
26135 @item @code{provision}
26136 This is a list of symbols denoting what the service provides.
26138 These are the names that may be passed to @command{herd start},
26139 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
26140 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
26141 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
26143 @item @code{requirement} (default: @code{'()})
26144 List of symbols denoting the Shepherd services this one depends on.
26146 @cindex one-shot services, for the Shepherd
26147 @item @code{one-shot?} (default: @code{#f})
26148 Whether this service is @dfn{one-shot}. One-shot services stop immediately
26149 after their @code{start} action has completed. @xref{Slots of services,,,
26150 shepherd, The GNU Shepherd Manual}, for more info.
26152 @item @code{respawn?} (default: @code{#t})
26153 Whether to restart the service when it stops, for instance when the
26154 underlying process dies.
26157 @itemx @code{stop} (default: @code{#~(const #f)})
26158 The @code{start} and @code{stop} fields refer to the Shepherd's
26159 facilities to start and stop processes (@pxref{Service De- and
26160 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
26161 G-expressions that get expanded in the Shepherd configuration file
26162 (@pxref{G-Expressions}).
26164 @item @code{actions} (default: @code{'()})
26165 @cindex actions, of Shepherd services
26166 This is a list of @code{shepherd-action} objects (see below) defining
26167 @dfn{actions} supported by the service, in addition to the standard
26168 @code{start} and @code{stop} actions. Actions listed here become available as
26169 @command{herd} sub-commands:
26172 herd @var{action} @var{service} [@var{arguments}@dots{}]
26175 @item @code{auto-start?} (default: @code{#t})
26176 Whether this service should be started automatically by the Shepherd. If it
26177 is @code{#f} the service has to be started manually with @code{herd start}.
26179 @item @code{documentation}
26180 A documentation string, as shown when running:
26183 herd doc @var{service-name}
26186 where @var{service-name} is one of the symbols in @code{provision}
26187 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
26189 @item @code{modules} (default: @code{%default-modules})
26190 This is the list of modules that must be in scope when @code{start} and
26191 @code{stop} are evaluated.
26196 @deftp {Data Type} shepherd-action
26197 This is the data type that defines additional actions implemented by a
26198 Shepherd service (see above).
26202 Symbol naming the action.
26204 @item documentation
26205 This is a documentation string for the action. It can be viewed by running:
26208 herd doc @var{service} action @var{action}
26212 This should be a gexp that evaluates to a procedure of at least one argument,
26213 which is the ``running value'' of the service (@pxref{Slots of services,,,
26214 shepherd, The GNU Shepherd Manual}).
26217 The following example defines an action called @code{say-hello} that kindly
26223 (documentation "Say hi!")
26224 (procedure #~(lambda (running . args)
26225 (format #t "Hello, friend! arguments: ~s\n"
26230 Assuming this action is added to the @code{example} service, then you can do:
26233 # herd say-hello example
26234 Hello, friend! arguments: ()
26235 # herd say-hello example a b c
26236 Hello, friend! arguments: ("a" "b" "c")
26239 This, as you can see, is a fairly sophisticated way to say hello.
26240 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
26244 @defvr {Scheme Variable} shepherd-root-service-type
26245 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
26247 This is the service type that extensions target when they want to create
26248 shepherd services (@pxref{Service Types and Services}, for an example).
26249 Each extension must pass a list of @code{<shepherd-service>}.
26252 @defvr {Scheme Variable} %shepherd-root-service
26253 This service represents PID@tie{}1.
26257 @node Documentation
26258 @chapter Documentation
26260 @cindex documentation, searching for
26261 @cindex searching for documentation
26262 @cindex Info, documentation format
26264 @cindex manual pages
26265 In most cases packages installed with Guix come with documentation.
26266 There are two main documentation formats: ``Info'', a browseable
26267 hypertext format used for GNU software, and ``manual pages'' (or ``man
26268 pages''), the linear documentation format traditionally found on Unix.
26269 Info manuals are accessed with the @command{info} command or with Emacs,
26270 and man pages are accessed using @command{man}.
26272 You can look for documentation of software installed on your system by
26273 keyword. For example, the following command searches for information
26274 about ``TLS'' in Info manuals:
26278 "(emacs)Network Security" -- STARTTLS
26279 "(emacs)Network Security" -- TLS
26280 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
26281 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
26286 The command below searches for the same keyword in man pages:
26290 SSL (7) - OpenSSL SSL/TLS library
26291 certtool (1) - GnuTLS certificate tool
26295 These searches are purely local to your computer so you have the
26296 guarantee that documentation you find corresponds to what you have
26297 actually installed, you can access it off-line, and your privacy is
26300 Once you have these results, you can view the relevant documentation by
26304 $ info "(gnutls)Core TLS API"
26314 Info manuals contain sections and indices as well as hyperlinks like
26315 those found in Web pages. The @command{info} reader (@pxref{Top, Info
26316 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
26317 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
26318 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
26319 Introduction}, for an introduction to Info navigation.
26321 @node Installing Debugging Files
26322 @chapter Installing Debugging Files
26324 @cindex debugging files
26325 Program binaries, as produced by the GCC compilers for instance, are
26326 typically written in the ELF format, with a section containing
26327 @dfn{debugging information}. Debugging information is what allows the
26328 debugger, GDB, to map binary code to source code; it is required to
26329 debug a compiled program in good conditions.
26331 The problem with debugging information is that is takes up a fair amount
26332 of disk space. For example, debugging information for the GNU C Library
26333 weighs in at more than 60 MiB. Thus, as a user, keeping all the
26334 debugging info of all the installed programs is usually not an option.
26335 Yet, space savings should not come at the cost of an impediment to
26336 debugging---especially in the GNU system, which should make it easier
26337 for users to exert their computing freedom (@pxref{GNU Distribution}).
26339 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
26340 mechanism that allows users to get the best of both worlds: debugging
26341 information can be stripped from the binaries and stored in separate
26342 files. GDB is then able to load debugging information from those files,
26343 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
26346 The GNU distribution takes advantage of this by storing debugging
26347 information in the @code{lib/debug} sub-directory of a separate package
26348 output unimaginatively called @code{debug} (@pxref{Packages with
26349 Multiple Outputs}). Users can choose to install the @code{debug} output
26350 of a package when they need it. For instance, the following command
26351 installs the debugging information for the GNU C Library and for GNU
26355 guix install glibc:debug guile:debug
26358 GDB must then be told to look for debug files in the user's profile, by
26359 setting the @code{debug-file-directory} variable (consider setting it
26360 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
26364 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
26367 From there on, GDB will pick up debugging information from the
26368 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
26370 In addition, you will most likely want GDB to be able to show the source
26371 code being debugged. To do that, you will have to unpack the source
26372 code of the package of interest (obtained with @code{guix build
26373 --source}, @pxref{Invoking guix build}), and to point GDB to that source
26374 directory using the @code{directory} command (@pxref{Source Path,
26375 @code{directory},, gdb, Debugging with GDB}).
26377 @c XXX: keep me up-to-date
26378 The @code{debug} output mechanism in Guix is implemented by the
26379 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
26380 opt-in---debugging information is available only for the packages
26381 with definitions explicitly declaring a @code{debug} output. This may be
26382 changed to opt-out in the future if our build farm servers can handle
26383 the load. To check whether a package has a @code{debug} output, use
26384 @command{guix package --list-available} (@pxref{Invoking guix package}).
26387 @node Security Updates
26388 @chapter Security Updates
26390 @cindex security updates
26391 @cindex security vulnerabilities
26392 Occasionally, important security vulnerabilities are discovered in software
26393 packages and must be patched. Guix developers try hard to keep track of
26394 known vulnerabilities and to apply fixes as soon as possible in the
26395 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
26396 containing only security updates.) The @command{guix lint} tool helps
26397 developers find out about vulnerable versions of software packages in the
26402 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
26403 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
26404 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
26408 @xref{Invoking guix lint}, for more information.
26410 Guix follows a functional
26411 package management discipline (@pxref{Introduction}), which implies
26412 that, when a package is changed, @emph{every package that depends on it}
26413 must be rebuilt. This can significantly slow down the deployment of
26414 fixes in core packages such as libc or Bash, since basically the whole
26415 distribution would need to be rebuilt. Using pre-built binaries helps
26416 (@pxref{Substitutes}), but deployment may still take more time than
26420 To address this, Guix implements @dfn{grafts}, a mechanism that allows
26421 for fast deployment of critical updates without the costs associated
26422 with a whole-distribution rebuild. The idea is to rebuild only the
26423 package that needs to be patched, and then to ``graft'' it onto packages
26424 explicitly installed by the user and that were previously referring to
26425 the original package. The cost of grafting is typically very low, and
26426 order of magnitudes lower than a full rebuild of the dependency chain.
26428 @cindex replacements of packages, for grafts
26429 For instance, suppose a security update needs to be applied to Bash.
26430 Guix developers will provide a package definition for the ``fixed''
26431 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
26432 Packages}). Then, the original package definition is augmented with a
26433 @code{replacement} field pointing to the package containing the bug fix:
26440 (replacement bash-fixed)))
26443 From there on, any package depending directly or indirectly on Bash---as
26444 reported by @command{guix gc --requisites} (@pxref{Invoking guix
26445 gc})---that is installed is automatically ``rewritten'' to refer to
26446 @code{bash-fixed} instead of @code{bash}. This grafting process takes
26447 time proportional to the size of the package, usually less than a
26448 minute for an ``average'' package on a recent machine. Grafting is
26449 recursive: when an indirect dependency requires grafting, then grafting
26450 ``propagates'' up to the package that the user is installing.
26452 Currently, the length of the name and version of the graft and that of
26453 the package it replaces (@code{bash-fixed} and @code{bash} in the example
26454 above) must be equal. This restriction mostly comes from the fact that
26455 grafting works by patching files, including binary files, directly.
26456 Other restrictions may apply: for instance, when adding a graft to a
26457 package providing a shared library, the original shared library and its
26458 replacement must have the same @code{SONAME} and be binary-compatible.
26460 The @option{--no-grafts} command-line option allows you to forcefully
26461 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
26465 guix build bash --no-grafts
26469 returns the store file name of the original Bash, whereas:
26476 returns the store file name of the ``fixed'', replacement Bash. This
26477 allows you to distinguish between the two variants of Bash.
26479 To verify which Bash your whole profile refers to, you can run
26480 (@pxref{Invoking guix gc}):
26483 guix gc -R `readlink -f ~/.guix-profile` | grep bash
26487 @dots{} and compare the store file names that you get with those above.
26488 Likewise for a complete Guix system generation:
26491 guix gc -R `guix system build my-config.scm` | grep bash
26494 Lastly, to check which Bash running processes are using, you can use the
26495 @command{lsof} command:
26498 lsof | grep /gnu/store/.*bash
26502 @node Bootstrapping
26503 @chapter Bootstrapping
26505 @c Adapted from the ELS 2013 paper.
26507 @cindex bootstrapping
26509 Bootstrapping in our context refers to how the distribution gets built
26510 ``from nothing''. Remember that the build environment of a derivation
26511 contains nothing but its declared inputs (@pxref{Introduction}). So
26512 there's an obvious chicken-and-egg problem: how does the first package
26513 get built? How does the first compiler get compiled? Note that this is
26514 a question of interest only to the curious hacker, not to the regular
26515 user, so you can shamelessly skip this section if you consider yourself
26516 a ``regular user''.
26518 @cindex bootstrap binaries
26519 The GNU system is primarily made of C code, with libc at its core. The
26520 GNU build system itself assumes the availability of a Bourne shell and
26521 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
26522 `grep'. Furthermore, build programs---programs that run
26523 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
26524 (@pxref{Derivations}). Consequently, to be able to build anything at
26525 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
26526 Binutils, libc, and the other packages mentioned above---the
26527 @dfn{bootstrap binaries}.
26529 These bootstrap binaries are ``taken for granted'', though we can also
26530 re-create them if needed (more on that later).
26532 @unnumberedsec Preparing to Use the Bootstrap Binaries
26534 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
26535 @c large image, it's hard to scroll. Oh well.
26536 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
26538 The figure above shows the very beginning of the dependency graph of the
26539 distribution, corresponding to the package definitions of the @code{(gnu
26540 packages bootstrap)} module. A similar figure can be generated with
26541 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
26544 guix graph -t derivation \
26545 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
26549 At this level of detail, things are
26550 slightly complex. First, Guile itself consists of an ELF executable,
26551 along with many source and compiled Scheme files that are dynamically
26552 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
26553 tarball shown in this graph. This tarball is part of Guix's ``source''
26554 distribution, and gets inserted into the store with @code{add-to-store}
26555 (@pxref{The Store}).
26557 But how do we write a derivation that unpacks this tarball and adds it
26558 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
26559 derivation---the first one that gets built---uses @code{bash} as its
26560 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
26561 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
26562 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
26563 the Guix source distribution, whose sole purpose is to allow the Guile
26564 tarball to be unpacked.
26566 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
26567 Guile that can be used to run subsequent build programs. Its first task
26568 is to download tarballs containing the other pre-built binaries---this
26569 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
26570 @code{ftp-client.scm} are used for this purpose. The
26571 @code{module-import.drv} derivations import those modules in a directory
26572 in the store, using the original layout. The
26573 @code{module-import-compiled.drv} derivations compile those modules, and
26574 write them in an output directory with the right layout. This
26575 corresponds to the @code{#:modules} argument of
26576 @code{build-expression->derivation} (@pxref{Derivations}).
26578 Finally, the various tarballs are unpacked by the
26579 derivations @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv},
26580 etc., at which point we have a working C tool chain.
26583 @unnumberedsec Building the Build Tools
26585 Bootstrapping is complete when we have a full tool chain that does not
26586 depend on the pre-built bootstrap tools discussed above. This
26587 no-dependency requirement is verified by checking whether the files of
26588 the final tool chain contain references to the @file{/gnu/store}
26589 directories of the bootstrap inputs. The process that leads to this
26590 ``final'' tool chain is described by the package definitions found in
26591 the @code{(gnu packages commencement)} module.
26593 The @command{guix graph} command allows us to ``zoom out'' compared to
26594 the graph above, by looking at the level of package objects instead of
26595 individual derivations---remember that a package may translate to
26596 several derivations, typically one derivation to download its source,
26597 one to build the Guile modules it needs, and one to actually build the
26598 package from source. The command:
26601 guix graph -t bag \
26602 -e '(@@@@ (gnu packages commencement)
26603 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
26607 produces the dependency graph leading to the ``final'' C
26608 library@footnote{You may notice the @code{glibc-intermediate} label,
26609 suggesting that it is not @emph{quite} final, but as a good
26610 approximation, we will consider it final.}, depicted below.
26612 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
26614 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
26615 The first tool that gets built with the bootstrap binaries is
26616 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
26617 for all the following packages. From there Findutils and Diffutils get
26620 Then come the first-stage Binutils and GCC, built as pseudo cross
26621 tools---i.e., with @code{--target} equal to @code{--host}. They are
26622 used to build libc. Thanks to this cross-build trick, this libc is
26623 guaranteed not to hold any reference to the initial tool chain.
26625 From there the final Binutils and GCC (not shown above) are built.
26627 from the final Binutils, and links programs against the just-built libc.
26628 This tool chain is used to build the other packages used by Guix and by
26629 the GNU Build System: Guile, Bash, Coreutils, etc.
26631 And voilà! At this point we have the complete set of build tools that
26632 the GNU Build System expects. These are in the @code{%final-inputs}
26633 variable of the @code{(gnu packages commencement)} module, and are
26634 implicitly used by any package that uses @code{gnu-build-system}
26635 (@pxref{Build Systems, @code{gnu-build-system}}).
26638 @unnumberedsec Building the Bootstrap Binaries
26640 @cindex bootstrap binaries
26641 Because the final tool chain does not depend on the bootstrap binaries,
26642 those rarely need to be updated. Nevertheless, it is useful to have an
26643 automated way to produce them, should an update occur, and this is what
26644 the @code{(gnu packages make-bootstrap)} module provides.
26646 The following command builds the tarballs containing the bootstrap
26647 binaries (Guile, Binutils, GCC, libc, and a tarball containing a mixture
26648 of Coreutils and other basic command-line tools):
26651 guix build bootstrap-tarballs
26654 The generated tarballs are those that should be referred to in the
26655 @code{(gnu packages bootstrap)} module mentioned at the beginning of
26658 Still here? Then perhaps by now you've started to wonder: when do we
26659 reach a fixed point? That is an interesting question! The answer is
26660 unknown, but if you would like to investigate further (and have
26661 significant computational and storage resources to do so), then let us
26664 @unnumberedsec Reducing the Set of Bootstrap Binaries
26666 Our bootstrap binaries currently include GCC, Guile, etc. That's a lot
26667 of binary code! Why is that a problem? It's a problem because these
26668 big chunks of binary code are practically non-auditable, which makes it
26669 hard to establish what source code produced them. Every unauditable
26670 binary also leaves us vulnerable to compiler backdoors as described by
26671 Ken Thompson in the 1984 paper @emph{Reflections on Trusting Trust}.
26673 This is mitigated by the fact that our bootstrap binaries were generated
26674 from an earlier Guix revision. Nevertheless it lacks the level of
26675 transparency that we get in the rest of the package dependency graph,
26676 where Guix always gives us a source-to-binary mapping. Thus, our goal
26677 is to reduce the set of bootstrap binaries to the bare minimum.
26679 The @uref{http://bootstrappable.org, Bootstrappable.org web site} lists
26680 on-going projects to do that. One of these is about replacing the
26681 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
26682 of increasing complexity, which could be built from source starting from
26683 a simple and auditable assembler. Your help is welcome!
26687 @chapter Porting to a New Platform
26689 As discussed above, the GNU distribution is self-contained, and
26690 self-containment is achieved by relying on pre-built ``bootstrap
26691 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
26692 operating system kernel, CPU architecture, and application binary
26693 interface (ABI). Thus, to port the distribution to a platform that is
26694 not yet supported, one must build those bootstrap binaries, and update
26695 the @code{(gnu packages bootstrap)} module to use them on that platform.
26697 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
26698 When everything goes well, and assuming the GNU tool chain supports the
26699 target platform, this can be as simple as running a command like this
26703 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
26706 For this to work, the @code{glibc-dynamic-linker} procedure in
26707 @code{(gnu packages bootstrap)} must be augmented to return the right
26708 file name for libc's dynamic linker on that platform; likewise,
26709 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
26710 taught about the new platform.
26712 Once these are built, the @code{(gnu packages bootstrap)} module needs
26713 to be updated to refer to these binaries on the target platform. That
26714 is, the hashes and URLs of the bootstrap tarballs for the new platform
26715 must be added alongside those of the currently supported platforms. The
26716 bootstrap Guile tarball is treated specially: it is expected to be
26717 available locally, and @file{gnu/local.mk} has rules to download it for
26718 the supported architectures; a rule for the new platform must be added
26721 In practice, there may be some complications. First, it may be that the
26722 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
26723 above) is not recognized by all the GNU tools. Typically, glibc
26724 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
26725 configure flag (see @code{gcc.scm} for examples of how to handle this).
26726 Second, some of the required packages could fail to build for that
26727 platform. Lastly, the generated binaries could be broken for some
26730 @c *********************************************************************
26731 @include contributing.texi
26733 @c *********************************************************************
26734 @node Acknowledgments
26735 @chapter Acknowledgments
26737 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
26738 which was designed and
26739 implemented by Eelco Dolstra, with contributions from other people (see
26740 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
26741 management, and promoted unprecedented features, such as transactional
26742 package upgrades and rollbacks, per-user profiles, and referentially
26743 transparent build processes. Without this work, Guix would not exist.
26745 The Nix-based software distributions, Nixpkgs and NixOS, have also been
26746 an inspiration for Guix.
26748 GNU@tie{}Guix itself is a collective work with contributions from a
26749 number of people. See the @file{AUTHORS} file in Guix for more
26750 information on these fine people. The @file{THANKS} file lists people
26751 who have helped by reporting bugs, taking care of the infrastructure,
26752 providing artwork and themes, making suggestions, and more---thank you!
26755 @c *********************************************************************
26756 @node GNU Free Documentation License
26757 @appendix GNU Free Documentation License
26758 @cindex license, GNU Free Documentation License
26759 @include fdl-1.3.texi
26761 @c *********************************************************************
26762 @node Concept Index
26763 @unnumbered Concept Index
26766 @node Programming Index
26767 @unnumbered Programming Index
26768 @syncodeindex tp fn
26769 @syncodeindex vr fn
26774 @c Local Variables:
26775 @c ispell-local-dictionary: "american";