6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
14 @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=15145
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER ci.guix.gnu.org
21 @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
24 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès@*
25 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
26 Copyright @copyright{} 2013 Nikita Karetnikov@*
27 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
28 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
29 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
30 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
31 Copyright @copyright{} 2015, 2016, 2017, 2019, 2020 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018, 2019 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017 Christopher Allan Webber@*
49 Copyright @copyright{} 2017, 2018, 2019, 2020 Marius Bakke@*
50 Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
51 Copyright @copyright{} 2017, 2019, 2020 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018, 2019, 2020 Tobias Geerinckx-Rice@*
53 Copyright @copyright{} 2017 George Clemmer@*
54 Copyright @copyright{} 2017 Andy Wingo@*
55 Copyright @copyright{} 2017, 2018, 2019 Arun Isaac@*
56 Copyright @copyright{} 2017 nee@*
57 Copyright @copyright{} 2018 Rutger Helling@*
58 Copyright @copyright{} 2018 Oleg Pykhalov@*
59 Copyright @copyright{} 2018 Mike Gerwitz@*
60 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
61 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
62 Copyright @copyright{} 2018, 2019 Florian Pelz@*
63 Copyright @copyright{} 2018 Laura Lazzati@*
64 Copyright @copyright{} 2018 Alex Vong@*
65 Copyright @copyright{} 2019 Josh Holland@*
66 Copyright @copyright{} 2019, 2020 Diego Nicola Barbato@*
67 Copyright @copyright{} 2019 Ivan Petkov@*
68 Copyright @copyright{} 2019 Jakob L. Kreuze@*
69 Copyright @copyright{} 2019 Kyle Andrews@*
70 Copyright @copyright{} 2019 Alex Griffin@*
71 Copyright @copyright{} 2019 Guillaume Le Vaillant@*
72 Copyright @copyright{} 2020 Leo Prikler@*
73 Copyright @copyright{} 2019, 2020 Simon Tournier@*
74 Copyright @copyright{} 2020 Wiktor Żelazny@*
75 Copyright @copyright{} 2020 Damien Cassou@*
76 Copyright @copyright{} 2020 Jakub Kądziołka@*
77 Copyright @copyright{} 2020 Jack Hill@*
78 Copyright @copyright{} 2020 Naga Malleswari@*
79 Copyright @copyright{} 2020 Brice Waegeneire@*
80 Copyright @copyright{} 2020 R Veera Kumar@*
81 Copyright @copyright{} 2020 Pierre Langlois@*
82 Copyright @copyright{} 2020 pinoaffe@*
84 Permission is granted to copy, distribute and/or modify this document
85 under the terms of the GNU Free Documentation License, Version 1.3 or
86 any later version published by the Free Software Foundation; with no
87 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
88 copy of the license is included in the section entitled ``GNU Free
89 Documentation License''.
92 @dircategory System administration
94 * Guix: (guix). Manage installed software and system configuration.
95 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
96 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
97 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
98 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
99 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
102 @dircategory Software development
104 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
105 * guix build: (guix)Invoking guix build. Building packages.
106 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
110 @title GNU Guix Reference Manual
111 @subtitle Using the GNU Guix Functional Package Manager
112 @author The GNU Guix Developers
115 @vskip 0pt plus 1filll
116 Edition @value{EDITION} @*
124 @c *********************************************************************
128 This document describes GNU Guix version @value{VERSION}, a functional
129 package management tool written for the GNU system.
131 @c TRANSLATORS: You can replace the following paragraph with information on
132 @c how to join your own translation team and how to report issues with the
134 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
135 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
136 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
137 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
138 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
139 would like to translate it in your native language, consider joining the
140 @uref{https://translationproject.org/domain/guix-manual.html, Translation
144 * Introduction:: What is Guix about?
145 * Installation:: Installing Guix.
146 * System Installation:: Installing the whole operating system.
147 * Package Management:: Package installation, upgrade, etc.
148 * Development:: Guix-aided software development.
149 * Programming Interface:: Using Guix in Scheme.
150 * Utilities:: Package management commands.
151 * System Configuration:: Configuring the operating system.
152 * Documentation:: Browsing software user manuals.
153 * Installing Debugging Files:: Feeding the debugger.
154 * Security Updates:: Deploying security fixes quickly.
155 * Bootstrapping:: GNU/Linux built from scratch.
156 * Porting:: Targeting another platform or kernel.
157 * Contributing:: Your help needed!
159 * Acknowledgments:: Thanks!
160 * GNU Free Documentation License:: The license of this manual.
161 * Concept Index:: Concepts.
162 * Programming Index:: Data types, functions, and variables.
165 --- The Detailed Node Listing ---
169 * Managing Software the Guix Way:: What's special.
170 * GNU Distribution:: The packages and tools.
174 * Binary Installation:: Getting Guix running in no time!
175 * Requirements:: Software needed to build and run Guix.
176 * Running the Test Suite:: Testing Guix.
177 * Setting Up the Daemon:: Preparing the build daemon's environment.
178 * Invoking guix-daemon:: Running the build daemon.
179 * Application Setup:: Application-specific setup.
181 Setting Up the Daemon
183 * Build Environment Setup:: Preparing the isolated build environment.
184 * Daemon Offload Setup:: Offloading builds to remote machines.
185 * SELinux Support:: Using an SELinux policy for the daemon.
189 * Limitations:: What you can expect.
190 * Hardware Considerations:: Supported hardware.
191 * USB Stick and DVD Installation:: Preparing the installation medium.
192 * Preparing for Installation:: Networking, partitioning, etc.
193 * Guided Graphical Installation:: Easy graphical installation.
194 * Manual Installation:: Manual installation for wizards.
195 * After System Installation:: When installation succeeded.
196 * Installing Guix in a VM:: Guix System playground.
197 * Building the Installation Image:: How this comes to be.
201 * Keyboard Layout and Networking and Partitioning:: Initial setup.
202 * Proceeding with the Installation:: Installing.
206 * Features:: How Guix will make your life brighter.
207 * Invoking guix package:: Package installation, removal, etc.
208 * Substitutes:: Downloading pre-built binaries.
209 * Packages with Multiple Outputs:: Single source package, multiple outputs.
210 * Invoking guix gc:: Running the garbage collector.
211 * Invoking guix pull:: Fetching the latest Guix and distribution.
212 * Channels:: Customizing the package collection.
213 * Invoking guix time-machine:: Running an older revision of Guix.
214 * Inferiors:: Interacting with another revision of Guix.
215 * Invoking guix describe:: Display information about your Guix revision.
216 * Invoking guix archive:: Exporting and importing store files.
220 * Official Substitute Server:: One particular source of substitutes.
221 * Substitute Server Authorization:: How to enable or disable substitutes.
222 * Substitute Authentication:: How Guix verifies substitutes.
223 * Proxy Settings:: How to get substitutes via proxy.
224 * Substitution Failure:: What happens when substitution fails.
225 * On Trusting Binaries:: How can you trust that binary blob?
229 * Invoking guix environment:: Setting up development environments.
230 * Invoking guix pack:: Creating software bundles.
231 * The GCC toolchain:: Working with languages supported by GCC.
233 Programming Interface
235 * Package Modules:: Packages from the programmer's viewpoint.
236 * Defining Packages:: Defining new packages.
237 * Build Systems:: Specifying how packages are built.
238 * The Store:: Manipulating the package store.
239 * Derivations:: Low-level interface to package derivations.
240 * The Store Monad:: Purely functional interface to the store.
241 * G-Expressions:: Manipulating build expressions.
242 * Invoking guix repl:: Fiddling with Guix interactively.
246 * package Reference:: The package data type.
247 * origin Reference:: The origin data type.
251 * Invoking guix build:: Building packages from the command line.
252 * Invoking guix edit:: Editing package definitions.
253 * Invoking guix download:: Downloading a file and printing its hash.
254 * Invoking guix hash:: Computing the cryptographic hash of a file.
255 * Invoking guix import:: Importing package definitions.
256 * Invoking guix refresh:: Updating package definitions.
257 * Invoking guix lint:: Finding errors in package definitions.
258 * Invoking guix size:: Profiling disk usage.
259 * Invoking guix graph:: Visualizing the graph of packages.
260 * Invoking guix publish:: Sharing substitutes.
261 * Invoking guix challenge:: Challenging substitute servers.
262 * Invoking guix copy:: Copying to and from a remote store.
263 * Invoking guix container:: Process isolation.
264 * Invoking guix weather:: Assessing substitute availability.
265 * Invoking guix processes:: Listing client processes.
267 Invoking @command{guix build}
269 * Common Build Options:: Build options for most commands.
270 * Package Transformation Options:: Creating variants of packages.
271 * Additional Build Options:: Options specific to 'guix build'.
272 * Debugging Build Failures:: Real life packaging experience.
276 * Using the Configuration System:: Customizing your GNU system.
277 * operating-system Reference:: Detail of operating-system declarations.
278 * File Systems:: Configuring file system mounts.
279 * Mapped Devices:: Block device extra processing.
280 * User Accounts:: Specifying user accounts.
281 * Keyboard Layout:: How the system interprets key strokes.
282 * Locales:: Language and cultural convention settings.
283 * Services:: Specifying system services.
284 * Setuid Programs:: Programs running with root privileges.
285 * X.509 Certificates:: Authenticating HTTPS servers.
286 * Name Service Switch:: Configuring libc's name service switch.
287 * Initial RAM Disk:: Linux-Libre bootstrapping.
288 * Bootloader Configuration:: Configuring the boot loader.
289 * Invoking guix system:: Instantiating a system configuration.
290 * Invoking guix deploy:: Deploying a system configuration to a remote host.
291 * Running Guix in a VM:: How to run Guix System in a virtual machine.
292 * Defining Services:: Adding new service definitions.
296 * Base Services:: Essential system services.
297 * Scheduled Job Execution:: The mcron service.
298 * Log Rotation:: The rottlog service.
299 * Networking Services:: Network setup, SSH daemon, etc.
300 * X Window:: Graphical display.
301 * Printing Services:: Local and remote printer support.
302 * Desktop Services:: D-Bus and desktop services.
303 * Sound Services:: ALSA and Pulseaudio services.
304 * Database Services:: SQL databases, key-value stores, etc.
305 * Mail Services:: IMAP, POP3, SMTP, and all that.
306 * Messaging Services:: Messaging services.
307 * Telephony Services:: Telephony services.
308 * Monitoring Services:: Monitoring services.
309 * Kerberos Services:: Kerberos services.
310 * Web Services:: Web servers.
311 * Certificate Services:: TLS certificates via Let's Encrypt.
312 * DNS Services:: DNS daemons.
313 * VPN Services:: VPN daemons.
314 * Network File System:: NFS related services.
315 * Continuous Integration:: The Cuirass service.
316 * Power Management Services:: Extending battery life.
317 * Audio Services:: The MPD.
318 * Virtualization Services:: Virtualization services.
319 * Version Control Services:: Providing remote access to Git repositories.
320 * Game Services:: Game servers.
321 * PAM Mount Service:: Service to mount volumes when logging in.
322 * Linux Services:: Services tied to the Linux kernel.
323 * Miscellaneous Services:: Other services.
327 * Service Composition:: The model for composing services.
328 * Service Types and Services:: Types and services.
329 * Service Reference:: API reference.
330 * Shepherd Services:: A particular type of service.
335 @c *********************************************************************
337 @chapter Introduction
340 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
341 using the international phonetic alphabet (IPA).} is a package
342 management tool for and distribution of the GNU system.
343 Guix makes it easy for unprivileged
344 users to install, upgrade, or remove software packages, to roll back to a
345 previous package set, to build packages from source, and generally
346 assists with the creation and maintenance of software environments.
349 @cindex GuixSD, now Guix System
350 @cindex Guix System Distribution, now Guix System
351 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
352 complements the available tools without interference (@pxref{Installation}),
353 or you can use it as a standalone operating system distribution,
354 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
355 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
356 group everything under the ``Guix'' banner since, after all, Guix System is
357 readily available through the @command{guix system} command, even if you're
358 using a different distro underneath!}. @xref{GNU Distribution}.
361 * Managing Software the Guix Way:: What's special.
362 * GNU Distribution:: The packages and tools.
365 @node Managing Software the Guix Way
366 @section Managing Software the Guix Way
368 @cindex user interfaces
369 Guix provides a command-line package management interface
370 (@pxref{Package Management}), tools to help with software development
371 (@pxref{Development}), command-line utilities for more advanced usage,
372 (@pxref{Utilities}), as well as Scheme programming interfaces
373 (@pxref{Programming Interface}).
375 Its @dfn{build daemon} is responsible for building packages on behalf of
376 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
377 binaries from authorized sources (@pxref{Substitutes}).
379 @cindex extensibility of the distribution
380 @cindex customization, of packages
381 Guix includes package definitions for many GNU and non-GNU packages, all
382 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
383 user's computing freedom}. It is @emph{extensible}: users can write
384 their own package definitions (@pxref{Defining Packages}) and make them
385 available as independent package modules (@pxref{Package Modules}). It
386 is also @emph{customizable}: users can @emph{derive} specialized package
387 definitions from existing ones, including from the command line
388 (@pxref{Package Transformation Options}).
390 @cindex functional package management
392 Under the hood, Guix implements the @dfn{functional package management}
393 discipline pioneered by Nix (@pxref{Acknowledgments}).
394 In Guix, the package build and installation process is seen
395 as a @emph{function}, in the mathematical sense. That function takes inputs,
396 such as build scripts, a compiler, and libraries, and
397 returns an installed package. As a pure function, its result depends
398 solely on its inputs---for instance, it cannot refer to software or
399 scripts that were not explicitly passed as inputs. A build function
400 always produces the same result when passed a given set of inputs. It
401 cannot alter the environment of the running system in
402 any way; for instance, it cannot create, modify, or delete files outside
403 of its build and installation directories. This is achieved by running
404 build processes in isolated environments (or @dfn{containers}), where only their
405 explicit inputs are visible.
408 The result of package build functions is @dfn{cached} in the file
409 system, in a special directory called @dfn{the store} (@pxref{The
410 Store}). Each package is installed in a directory of its own in the
411 store---by default under @file{/gnu/store}. The directory name contains
412 a hash of all the inputs used to build that package; thus, changing an
413 input yields a different directory name.
415 This approach is the foundation for the salient features of Guix: support
416 for transactional package upgrade and rollback, per-user installation, and
417 garbage collection of packages (@pxref{Features}).
420 @node GNU Distribution
421 @section GNU Distribution
424 Guix comes with a distribution of the GNU system consisting entirely of
425 free software@footnote{The term ``free'' here refers to the
426 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
427 users of that software}.}. The
428 distribution can be installed on its own (@pxref{System Installation}),
429 but it is also possible to install Guix as a package manager on top of
430 an installed GNU/Linux system (@pxref{Installation}). When we need to
431 distinguish between the two, we refer to the standalone distribution as
434 The distribution provides core GNU packages such as GNU libc, GCC, and
435 Binutils, as well as many GNU and non-GNU applications. The complete
436 list of available packages can be browsed
437 @url{https://www.gnu.org/software/guix/packages,on-line} or by
438 running @command{guix package} (@pxref{Invoking guix package}):
441 guix package --list-available
444 Our goal is to provide a practical 100% free software distribution of
445 Linux-based and other variants of GNU, with a focus on the promotion and
446 tight integration of GNU components, and an emphasis on programs and
447 tools that help users exert that freedom.
449 Packages are currently available on the following platforms:
454 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
457 Intel 32-bit architecture (IA32), Linux-Libre kernel;
460 ARMv7-A architecture with hard float, Thumb-2 and NEON,
461 using the EABI hard-float application binary interface (ABI),
462 and Linux-Libre kernel.
465 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
467 @item mips64el-linux (deprecated)
468 little-endian 64-bit MIPS processors, specifically the Loongson series,
469 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
470 supported; in particular, there is no ongoing work to ensure that this
471 architecture still works. Should someone decide they wish to revive this
472 architecture then the code is still available.
476 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
477 configuration and Guix takes care of instantiating the configuration in a
478 transactional, reproducible, and stateless fashion (@pxref{System
479 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
480 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
481 Manual}), the well-known GNU utilities and tool chain, as well as the
482 graphical environment or system services of your choice.
484 Guix System is available on all the above platforms except
485 @code{mips64el-linux}.
488 For information on porting to other architectures or kernels,
491 Building this distribution is a cooperative effort, and you are invited
492 to join! @xref{Contributing}, for information about how you can help.
495 @c *********************************************************************
497 @chapter Installation
499 @cindex installing Guix
502 We recommend the use of this
503 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
504 shell installer script} to install Guix on top of a running GNU/Linux system,
505 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
506 with the installation of the package manager, which can be done on top of a
507 running GNU/Linux system. If, instead, you want to install the complete GNU
508 operating system, @pxref{System Installation}.} The script automates the
509 download, installation, and initial configuration of Guix. It should be run
513 @cindex foreign distro
514 @cindex directories related to foreign distro
515 When installed on a foreign distro, GNU@tie{}Guix complements the available
516 tools without interference. Its data lives exclusively in two directories,
517 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
518 such as @file{/etc}, are left untouched.
520 Once installed, Guix can be updated by running @command{guix pull}
521 (@pxref{Invoking guix pull}).
523 If you prefer to perform the installation steps manually or want to tweak
524 them, you may find the following subsections useful. They describe the
525 software requirements of Guix, as well as how to install it manually and get
529 * Binary Installation:: Getting Guix running in no time!
530 * Requirements:: Software needed to build and run Guix.
531 * Running the Test Suite:: Testing Guix.
532 * Setting Up the Daemon:: Preparing the build daemon's environment.
533 * Invoking guix-daemon:: Running the build daemon.
534 * Application Setup:: Application-specific setup.
535 * Upgrading Guix:: Upgrading Guix and its build daemon.
538 @node Binary Installation
539 @section Binary Installation
541 @cindex installing Guix from binaries
542 @cindex installer script
543 This section describes how to install Guix on an arbitrary system from a
544 self-contained tarball providing binaries for Guix and for all its
545 dependencies. This is often quicker than installing from source, which
546 is described in the next sections. The only requirement is to have
549 @c Note duplicated from the ``Installation'' node.
551 We recommend the use of this
552 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
553 shell installer script}. The script automates the download, installation, and
554 initial configuration steps described below. It should be run as the root
555 user. As root, you can thus run this:
559 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
560 chmod +x guix-install.sh
565 Installing goes along these lines:
569 @cindex downloading Guix binary
570 Download the binary tarball from
571 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
572 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
573 @code{i686} (32-bits) machine already running the kernel Linux, and so on
574 (@pxref{GNU Distribution}).
576 @c The following is somewhat duplicated in ``System Installation''.
577 Make sure to download the associated @file{.sig} file and to verify the
578 authenticity of the tarball against it, along these lines:
581 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
582 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
585 If that command fails because you do not have the required public key,
586 then run this command to import it:
589 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
590 -qO - | gpg --import -
594 and rerun the @code{gpg --verify} command.
596 Take note that a warning like ``This key is not certified with a trusted
597 signature!'' is normal.
599 @c end authentication part
602 Now, you need to become the @code{root} user. Depending on your distribution,
603 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
607 # tar --warning=no-timestamp -xf \
608 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
609 # mv var/guix /var/ && mv gnu /
612 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
613 The latter contains a ready-to-use profile for @code{root} (see next
616 Do @emph{not} unpack the tarball on a working Guix system since that
617 would overwrite its own essential files.
619 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
620 not emit warnings about ``implausibly old time stamps'' (such
621 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
623 They stem from the fact that all the
624 files in the archive have their modification time set to zero (which
625 means January 1st, 1970). This is done on purpose to make sure the
626 archive content is independent of its creation time, thus making it
630 Make the profile available under @file{~root/.config/guix/current}, which is
631 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
634 # mkdir -p ~root/.config/guix
635 # ln -sf /var/guix/profiles/per-user/root/current-guix \
636 ~root/.config/guix/current
639 Source @file{etc/profile} to augment @env{PATH} and other relevant
640 environment variables:
643 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
644 source $GUIX_PROFILE/etc/profile
648 Create the group and user accounts for build users as explained below
649 (@pxref{Build Environment Setup}).
652 Run the daemon, and set it to automatically start on boot.
654 If your host distro uses the systemd init system, this can be achieved
657 @c Versions of systemd that supported symlinked service files are not
658 @c yet widely deployed, so we should suggest that users copy the service
661 @c See this thread for more information:
662 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
665 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
666 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
668 # systemctl enable --now gnu-store.mount guix-daemon
671 If your host distro uses the Upstart init system:
674 # initctl reload-configuration
675 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
680 Otherwise, you can still start the daemon manually with:
683 # ~root/.config/guix/current/bin/guix-daemon \
684 --build-users-group=guixbuild
688 Make the @command{guix} command available to other users on the machine,
692 # mkdir -p /usr/local/bin
694 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
697 It is also a good idea to make the Info version of this manual available
701 # mkdir -p /usr/local/share/info
702 # cd /usr/local/share/info
703 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
707 That way, assuming @file{/usr/local/share/info} is in the search path,
708 running @command{info guix} will open this manual (@pxref{Other Info
709 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
713 @cindex substitutes, authorization thereof
714 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
715 (@pxref{Substitutes}), authorize them:
718 # guix archive --authorize < \
719 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
723 Each user may need to perform a few additional steps to make their Guix
724 environment ready for use, @pxref{Application Setup}.
727 Voilà, the installation is complete!
729 You can confirm that Guix is working by installing a sample package into
736 The binary installation tarball can be (re)produced and verified simply
737 by running the following command in the Guix source tree:
740 make guix-binary.@var{system}.tar.xz
744 ...@: which, in turn, runs:
747 guix pack -s @var{system} --localstatedir \
748 --profile-name=current-guix guix
751 @xref{Invoking guix pack}, for more info on this handy tool.
754 @section Requirements
756 This section lists requirements when building Guix from source. The
757 build procedure for Guix is the same as for other GNU software, and is
758 not covered here. Please see the files @file{README} and @file{INSTALL}
759 in the Guix source tree for additional details.
761 @cindex official website
762 GNU Guix is available for download from its website at
763 @url{https://www.gnu.org/software/guix/}.
765 GNU Guix depends on the following packages:
768 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
770 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
773 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
774 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
775 Guile,, gnutls-guile, GnuTLS-Guile});
777 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
780 @c FIXME: Specify a version number once a release has been made.
781 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
783 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON} 3.x;
784 @item @url{https://zlib.net, zlib};
785 @item @url{https://www.gnu.org/software/make/, GNU Make}.
788 The following dependencies are optional:
792 @c Note: We need at least 0.12.0 for 'userauth-gssapi!'.
793 Support for build offloading (@pxref{Daemon Offload Setup}) and
794 @command{guix copy} (@pxref{Invoking guix copy}) depends on
795 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
796 version 0.12.0 or later.
799 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
800 substitutes can be used and @command{guix publish} can compress substitutes
804 When @url{http://www.bzip.org, libbz2} is available,
805 @command{guix-daemon} can use it to compress build logs.
808 Unless @option{--disable-daemon} was passed to @command{configure}, the
809 following packages are also needed:
812 @item @url{https://gnupg.org/, GNU libgcrypt};
813 @item @url{https://sqlite.org, SQLite 3};
814 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
818 @cindex state directory
819 When configuring Guix on a system that already has a Guix installation,
820 be sure to specify the same state directory as the existing installation
821 using the @option{--localstatedir} option of the @command{configure}
822 script (@pxref{Directory Variables, @code{localstatedir},, standards,
823 GNU Coding Standards}). Usually, this @var{localstatedir} option is
824 set to the value @file{/var}. The @command{configure} script protects
825 against unintended misconfiguration of @var{localstatedir} so you do not
826 inadvertently corrupt your store (@pxref{The Store}).
828 @node Running the Test Suite
829 @section Running the Test Suite
832 After a successful @command{configure} and @code{make} run, it is a good
833 idea to run the test suite. It can help catch issues with the setup or
834 environment, or bugs in Guix itself---and really, reporting test
835 failures is a good way to help improve the software. To run the test
842 Test cases can run in parallel: you can use the @code{-j} option of
843 GNU@tie{}make to speed things up. The first run may take a few minutes
844 on a recent machine; subsequent runs will be faster because the store
845 that is created for test purposes will already have various things in
848 It is also possible to run a subset of the tests by defining the
849 @code{TESTS} makefile variable as in this example:
852 make check TESTS="tests/store.scm tests/cpio.scm"
855 By default, tests results are displayed at a file level. In order to
856 see the details of every individual test cases, it is possible to define
857 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
860 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
863 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
864 @file{test-suite.log} file. Please specify the Guix version being used
865 as well as version numbers of the dependencies (@pxref{Requirements}) in
868 Guix also comes with a whole-system test suite that tests complete
869 Guix System instances. It can only run on systems where
870 Guix is already installed, using:
877 or, again, by defining @code{TESTS} to select a subset of tests to run:
880 make check-system TESTS="basic mcron"
883 These system tests are defined in the @code{(gnu tests @dots{})}
884 modules. They work by running the operating systems under test with
885 lightweight instrumentation in a virtual machine (VM). They can be
886 computationally intensive or rather cheap, depending on whether
887 substitutes are available for their dependencies (@pxref{Substitutes}).
888 Some of them require a lot of storage space to hold VM images.
890 Again in case of test failures, please send @email{bug-guix@@gnu.org}
893 @node Setting Up the Daemon
894 @section Setting Up the Daemon
897 Operations such as building a package or running the garbage collector
898 are all performed by a specialized process, the @dfn{build daemon}, on
899 behalf of clients. Only the daemon may access the store and its
900 associated database. Thus, any operation that manipulates the store
901 goes through the daemon. For instance, command-line tools such as
902 @command{guix package} and @command{guix build} communicate with the
903 daemon (@i{via} remote procedure calls) to instruct it what to do.
905 The following sections explain how to prepare the build daemon's
906 environment. See also @ref{Substitutes}, for information on how to allow
907 the daemon to download pre-built binaries.
910 * Build Environment Setup:: Preparing the isolated build environment.
911 * Daemon Offload Setup:: Offloading builds to remote machines.
912 * SELinux Support:: Using an SELinux policy for the daemon.
915 @node Build Environment Setup
916 @subsection Build Environment Setup
918 @cindex build environment
919 In a standard multi-user setup, Guix and its daemon---the
920 @command{guix-daemon} program---are installed by the system
921 administrator; @file{/gnu/store} is owned by @code{root} and
922 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
923 Guix tools to build packages or otherwise access the store, and the
924 daemon will do it on their behalf, ensuring that the store is kept in a
925 consistent state, and allowing built packages to be shared among users.
928 When @command{guix-daemon} runs as @code{root}, you may not want package
929 build processes themselves to run as @code{root} too, for obvious
930 security reasons. To avoid that, a special pool of @dfn{build users}
931 should be created for use by build processes started by the daemon.
932 These build users need not have a shell and a home directory: they will
933 just be used when the daemon drops @code{root} privileges in build
934 processes. Having several such users allows the daemon to launch
935 distinct build processes under separate UIDs, which guarantees that they
936 do not interfere with each other---an essential feature since builds are
937 regarded as pure functions (@pxref{Introduction}).
939 On a GNU/Linux system, a build user pool may be created like this (using
940 Bash syntax and the @code{shadow} commands):
942 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
943 @c for why `-G' is needed.
945 # groupadd --system guixbuild
946 # for i in `seq -w 1 10`;
948 useradd -g guixbuild -G guixbuild \
949 -d /var/empty -s `which nologin` \
950 -c "Guix build user $i" --system \
956 The number of build users determines how many build jobs may run in
957 parallel, as specified by the @option{--max-jobs} option
958 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
959 @command{guix system vm} and related commands, you may need to add the
960 build users to the @code{kvm} group so they can access @file{/dev/kvm},
961 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
962 (@pxref{Invoking guix system}).
964 The @code{guix-daemon} program may then be run as @code{root} with the
965 following command@footnote{If your machine uses the systemd init system,
966 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
967 file in @file{/etc/systemd/system} will ensure that
968 @command{guix-daemon} is automatically started. Similarly, if your
969 machine uses the Upstart init system, drop the
970 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
971 file in @file{/etc/init}.}:
974 # guix-daemon --build-users-group=guixbuild
979 This way, the daemon starts build processes in a chroot, under one of
980 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
981 environment contains nothing but:
983 @c Keep this list in sync with libstore/build.cc! -----------------------
986 a minimal @code{/dev} directory, created mostly independently from the
987 host @code{/dev}@footnote{``Mostly'', because while the set of files
988 that appear in the chroot's @code{/dev} is fixed, most of these files
989 can only be created if the host has them.};
992 the @code{/proc} directory; it only shows the processes of the container
993 since a separate PID name space is used;
996 @file{/etc/passwd} with an entry for the current user and an entry for
1000 @file{/etc/group} with an entry for the user's group;
1003 @file{/etc/hosts} with an entry that maps @code{localhost} to
1007 a writable @file{/tmp} directory.
1010 You can influence the directory where the daemon stores build trees
1011 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1012 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1013 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1014 This way, the value of @env{TMPDIR} does not leak inside build
1015 environments, which avoids discrepancies in cases where build processes
1016 capture the name of their build tree.
1020 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1021 environment variables for HTTP and HTTPS downloads it performs, be it
1022 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1023 (@pxref{Substitutes}).
1025 If you are installing Guix as an unprivileged user, it is still possible
1026 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1027 However, build processes will not be isolated from one another, and not
1028 from the rest of the system. Thus, build processes may interfere with
1029 each other, and may access programs, libraries, and other files
1030 available on the system---making it much harder to view them as
1031 @emph{pure} functions.
1034 @node Daemon Offload Setup
1035 @subsection Using the Offload Facility
1039 When desired, the build daemon can @dfn{offload} derivation builds to
1040 other machines running Guix, using the @code{offload} @dfn{build
1041 hook}@footnote{This feature is available only when
1042 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1043 present.}. When that
1044 feature is enabled, a list of user-specified build machines is read from
1045 @file{/etc/guix/machines.scm}; every time a build is requested, for
1046 instance via @code{guix build}, the daemon attempts to offload it to one
1047 of the machines that satisfy the constraints of the derivation, in
1048 particular its system type---e.g., @file{x86_64-linux}. Missing
1049 prerequisites for the build are copied over SSH to the target machine,
1050 which then proceeds with the build; upon success the output(s) of the
1051 build are copied back to the initial machine.
1053 The @file{/etc/guix/machines.scm} file typically looks like this:
1056 (list (build-machine
1057 (name "eightysix.example.org")
1058 (system "x86_64-linux")
1059 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1061 (speed 2.)) ;incredibly fast!
1064 (name "armeight.example.org")
1065 (system "aarch64-linux")
1066 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1069 (string-append (getenv "HOME")
1070 "/.ssh/identity-for-guix"))))
1074 In the example above we specify a list of two build machines, one for
1075 the @code{x86_64} architecture and one for the @code{aarch64}
1078 In fact, this file is---not surprisingly!---a Scheme file that is
1079 evaluated when the @code{offload} hook is started. Its return value
1080 must be a list of @code{build-machine} objects. While this example
1081 shows a fixed list of build machines, one could imagine, say, using
1082 DNS-SD to return a list of potential build machines discovered in the
1083 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1084 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1087 @deftp {Data Type} build-machine
1088 This data type represents build machines to which the daemon may offload
1089 builds. The important fields are:
1094 The host name of the remote machine.
1097 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1100 The user account to use when connecting to the remote machine over SSH.
1101 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1102 allow non-interactive logins.
1105 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1106 This is used to authenticate the machine when we connect to it. It is a
1107 long string that looks like this:
1110 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1113 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1114 key can be found in a file such as
1115 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1117 If the machine is running the SSH daemon of GNU@tie{}lsh,
1118 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1119 similar file. It can be converted to the OpenSSH format using
1120 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1123 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1124 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1129 A number of optional fields may be specified:
1133 @item @code{port} (default: @code{22})
1134 Port number of SSH server on the machine.
1136 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1137 The SSH private key file to use when connecting to the machine, in
1138 OpenSSH format. This key must not be protected with a passphrase.
1140 Note that the default value is the private key @emph{of the root
1141 account}. Make sure it exists if you use the default.
1143 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1144 @itemx @code{compression-level} (default: @code{3})
1145 The SSH-level compression methods and compression level requested.
1147 Note that offloading relies on SSH compression to reduce bandwidth usage
1148 when transferring files to and from build machines.
1150 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1151 File name of the Unix-domain socket @command{guix-daemon} is listening
1154 @item @code{parallel-builds} (default: @code{1})
1155 The number of builds that may run in parallel on the machine.
1157 @item @code{speed} (default: @code{1.0})
1158 A ``relative speed factor''. The offload scheduler will tend to prefer
1159 machines with a higher speed factor.
1161 @item @code{features} (default: @code{'()})
1162 A list of strings denoting specific features supported by the machine.
1163 An example is @code{"kvm"} for machines that have the KVM Linux modules
1164 and corresponding hardware support. Derivations can request features by
1165 name, and they will be scheduled on matching build machines.
1170 The @command{guix} command must be in the search path on the build
1171 machines. You can check whether this is the case by running:
1174 ssh build-machine guix repl --version
1177 There is one last thing to do once @file{machines.scm} is in place. As
1178 explained above, when offloading, files are transferred back and forth
1179 between the machine stores. For this to work, you first need to
1180 generate a key pair on each machine to allow the daemon to export signed
1181 archives of files from the store (@pxref{Invoking guix archive}):
1184 # guix archive --generate-key
1188 Each build machine must authorize the key of the master machine so that
1189 it accepts store items it receives from the master:
1192 # guix archive --authorize < master-public-key.txt
1196 Likewise, the master machine must authorize the key of each build machine.
1198 All the fuss with keys is here to express pairwise mutual trust
1199 relations between the master and the build machines. Concretely, when
1200 the master receives files from a build machine (and @i{vice versa}), its
1201 build daemon can make sure they are genuine, have not been tampered
1202 with, and that they are signed by an authorized key.
1204 @cindex offload test
1205 To test whether your setup is operational, run this command on the
1212 This will attempt to connect to each of the build machines specified in
1213 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1214 available on each machine, attempt to export to the machine and import
1215 from it, and report any error in the process.
1217 If you want to test a different machine file, just specify it on the
1221 # guix offload test machines-qualif.scm
1224 Last, you can test the subset of the machines whose name matches a
1225 regular expression like this:
1228 # guix offload test machines.scm '\.gnu\.org$'
1231 @cindex offload status
1232 To display the current load of all build hosts, run this command on the
1236 # guix offload status
1240 @node SELinux Support
1241 @subsection SELinux Support
1243 @cindex SELinux, daemon policy
1244 @cindex mandatory access control, SELinux
1245 @cindex security, guix-daemon
1246 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1247 can be installed on a system where SELinux is enabled, in order to label
1248 Guix files and to specify the expected behavior of the daemon. Since
1249 Guix System does not provide an SELinux base policy, the daemon policy cannot
1250 be used on Guix System.
1252 @subsubsection Installing the SELinux policy
1253 @cindex SELinux, policy installation
1254 To install the policy run this command as root:
1257 semodule -i etc/guix-daemon.cil
1260 Then relabel the file system with @code{restorecon} or by a different
1261 mechanism provided by your system.
1263 Once the policy is installed, the file system has been relabeled, and
1264 the daemon has been restarted, it should be running in the
1265 @code{guix_daemon_t} context. You can confirm this with the following
1269 ps -Zax | grep guix-daemon
1272 Monitor the SELinux log files as you run a command like @code{guix build
1273 hello} to convince yourself that SELinux permits all necessary
1276 @subsubsection Limitations
1277 @cindex SELinux, limitations
1279 This policy is not perfect. Here is a list of limitations or quirks
1280 that should be considered when deploying the provided SELinux policy for
1285 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1286 operations involve contexts that have anything to do with
1287 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1288 but it would be preferrable to define socket rules for only this label.
1291 @code{guix gc} cannot access arbitrary links to profiles. By design,
1292 the file label of the destination of a symlink is independent of the
1293 file label of the link itself. Although all profiles under
1294 $localstatedir are labelled, the links to these profiles inherit the
1295 label of the directory they are in. For links in the user’s home
1296 directory this will be @code{user_home_t}. But for links from the root
1297 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1298 directory, etc, this won’t work. @code{guix gc} would be prevented from
1299 reading and following these links.
1302 The daemon’s feature to listen for TCP connections might no longer work.
1303 This might require extra rules, because SELinux treats network sockets
1304 differently from files.
1307 Currently all files with a name matching the regular expression
1308 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1309 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1310 that name in any profile would be permitted to run in the
1311 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1312 build a package that provides this executable and convince a user to
1313 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1314 At that point SELinux could not prevent it from accessing files that are
1315 allowed for processes in that domain.
1317 We could generate a much more restrictive policy at installation time,
1318 so that only the @emph{exact} file name of the currently installed
1319 @code{guix-daemon} executable would be labelled with
1320 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1321 The downside is that root would have to install or upgrade the policy at
1322 installation time whenever the Guix package that provides the
1323 effectively running @code{guix-daemon} executable is upgraded.
1326 @node Invoking guix-daemon
1327 @section Invoking @command{guix-daemon}
1329 The @command{guix-daemon} program implements all the functionality to
1330 access the store. This includes launching build processes, running the
1331 garbage collector, querying the availability of a build result, etc. It
1332 is normally run as @code{root} like this:
1335 # guix-daemon --build-users-group=guixbuild
1339 For details on how to set it up, @pxref{Setting Up the Daemon}.
1342 @cindex container, build environment
1343 @cindex build environment
1344 @cindex reproducible builds
1345 By default, @command{guix-daemon} launches build processes under
1346 different UIDs, taken from the build group specified with
1347 @option{--build-users-group}. In addition, each build process is run in a
1348 chroot environment that only contains the subset of the store that the
1349 build process depends on, as specified by its derivation
1350 (@pxref{Programming Interface, derivation}), plus a set of specific
1351 system directories. By default, the latter contains @file{/dev} and
1352 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1353 @dfn{container}: in addition to having its own file system tree, it has
1354 a separate mount name space, its own PID name space, network name space,
1355 etc. This helps achieve reproducible builds (@pxref{Features}).
1357 When the daemon performs a build on behalf of the user, it creates a
1358 build directory under @file{/tmp} or under the directory specified by
1359 its @env{TMPDIR} environment variable. This directory is shared with
1360 the container for the duration of the build, though within the container,
1361 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1363 The build directory is automatically deleted upon completion, unless the
1364 build failed and the client specified @option{--keep-failed}
1365 (@pxref{Invoking guix build, @option{--keep-failed}}).
1367 The daemon listens for connections and spawns one sub-process for each session
1368 started by a client (one of the @command{guix} sub-commands). The
1369 @command{guix processes} command allows you to get an overview of the activity
1370 on your system by viewing each of the active sessions and clients.
1371 @xref{Invoking guix processes}, for more information.
1373 The following command-line options are supported:
1376 @item --build-users-group=@var{group}
1377 Take users from @var{group} to run build processes (@pxref{Setting Up
1378 the Daemon, build users}).
1380 @item --no-substitutes
1382 Do not use substitutes for build products. That is, always build things
1383 locally instead of allowing downloads of pre-built binaries
1384 (@pxref{Substitutes}).
1386 When the daemon runs with @option{--no-substitutes}, clients can still
1387 explicitly enable substitution @i{via} the @code{set-build-options}
1388 remote procedure call (@pxref{The Store}).
1390 @item --substitute-urls=@var{urls}
1391 @anchor{daemon-substitute-urls}
1392 Consider @var{urls} the default whitespace-separated list of substitute
1393 source URLs. When this option is omitted,
1394 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1396 This means that substitutes may be downloaded from @var{urls}, as long
1397 as they are signed by a trusted signature (@pxref{Substitutes}).
1401 Do not use offload builds to other machines (@pxref{Daemon Offload
1402 Setup}). That is, always build things locally instead of offloading
1403 builds to remote machines.
1405 @item --cache-failures
1406 Cache build failures. By default, only successful builds are cached.
1408 When this option is used, @command{guix gc --list-failures} can be used
1409 to query the set of store items marked as failed; @command{guix gc
1410 --clear-failures} removes store items from the set of cached failures.
1411 @xref{Invoking guix gc}.
1413 @item --cores=@var{n}
1415 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1418 The default value is @code{0}, but it may be overridden by clients, such
1419 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1422 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1423 in the build process, which can then use it to exploit internal
1424 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1426 @item --max-jobs=@var{n}
1428 Allow at most @var{n} build jobs in parallel. The default value is
1429 @code{1}. Setting it to @code{0} means that no builds will be performed
1430 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1431 Setup}), or simply fail.
1433 @item --max-silent-time=@var{seconds}
1434 When the build or substitution process remains silent for more than
1435 @var{seconds}, terminate it and report a build failure.
1437 The default value is @code{0}, which disables the timeout.
1439 The value specified here can be overridden by clients (@pxref{Common
1440 Build Options, @option{--max-silent-time}}).
1442 @item --timeout=@var{seconds}
1443 Likewise, when the build or substitution process lasts for more than
1444 @var{seconds}, terminate it and report a build failure.
1446 The default value is @code{0}, which disables the timeout.
1448 The value specified here can be overridden by clients (@pxref{Common
1449 Build Options, @option{--timeout}}).
1451 @item --rounds=@var{N}
1452 Build each derivation @var{n} times in a row, and raise an error if
1453 consecutive build results are not bit-for-bit identical. Note that this
1454 setting can be overridden by clients such as @command{guix build}
1455 (@pxref{Invoking guix build}).
1457 When used in conjunction with @option{--keep-failed}, the differing
1458 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1459 This makes it easy to look for differences between the two results.
1462 Produce debugging output.
1464 This is useful to debug daemon start-up issues, but then it may be
1465 overridden by clients, for example the @option{--verbosity} option of
1466 @command{guix build} (@pxref{Invoking guix build}).
1468 @item --chroot-directory=@var{dir}
1469 Add @var{dir} to the build chroot.
1471 Doing this may change the result of build processes---for instance if
1472 they use optional dependencies found in @var{dir} when it is available,
1473 and not otherwise. For that reason, it is not recommended to do so.
1474 Instead, make sure that each derivation declares all the inputs that it
1477 @item --disable-chroot
1478 Disable chroot builds.
1480 Using this option is not recommended since, again, it would allow build
1481 processes to gain access to undeclared dependencies. It is necessary,
1482 though, when @command{guix-daemon} is running under an unprivileged user
1485 @item --log-compression=@var{type}
1486 Compress build logs according to @var{type}, one of @code{gzip},
1487 @code{bzip2}, or @code{none}.
1489 Unless @option{--lose-logs} is used, all the build logs are kept in the
1490 @var{localstatedir}. To save space, the daemon automatically compresses
1491 them with Bzip2 by default.
1493 @item --disable-deduplication
1494 @cindex deduplication
1495 Disable automatic file ``deduplication'' in the store.
1497 By default, files added to the store are automatically ``deduplicated'':
1498 if a newly added file is identical to another one found in the store,
1499 the daemon makes the new file a hard link to the other file. This can
1500 noticeably reduce disk usage, at the expense of slightly increased
1501 input/output load at the end of a build process. This option disables
1504 @item --gc-keep-outputs[=yes|no]
1505 Tell whether the garbage collector (GC) must keep outputs of live
1509 @cindex garbage collector roots
1510 When set to @code{yes}, the GC will keep the outputs of any live
1511 derivation available in the store---the @file{.drv} files. The default
1512 is @code{no}, meaning that derivation outputs are kept only if they are
1513 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1516 @item --gc-keep-derivations[=yes|no]
1517 Tell whether the garbage collector (GC) must keep derivations
1518 corresponding to live outputs.
1520 When set to @code{yes}, as is the case by default, the GC keeps
1521 derivations---i.e., @file{.drv} files---as long as at least one of their
1522 outputs is live. This allows users to keep track of the origins of
1523 items in their store. Setting it to @code{no} saves a bit of disk
1526 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1527 liveness to flow from outputs to derivations, and setting
1528 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1529 derivations to outputs. When both are set to @code{yes}, the effect is
1530 to keep all the build prerequisites (the sources, compiler, libraries,
1531 and other build-time tools) of live objects in the store, regardless of
1532 whether these prerequisites are reachable from a GC root. This is
1533 convenient for developers since it saves rebuilds or downloads.
1535 @item --impersonate-linux-2.6
1536 On Linux-based systems, impersonate Linux 2.6. This means that the
1537 kernel's @command{uname} system call will report 2.6 as the release number.
1539 This might be helpful to build programs that (usually wrongfully) depend
1540 on the kernel version number.
1543 Do not keep build logs. By default they are kept under
1544 @file{@var{localstatedir}/guix/log}.
1546 @item --system=@var{system}
1547 Assume @var{system} as the current system type. By default it is the
1548 architecture/kernel pair found at configure time, such as
1549 @code{x86_64-linux}.
1551 @item --listen=@var{endpoint}
1552 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1553 as the file name of a Unix-domain socket if it starts with
1554 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1555 host name or host name and port to listen to. Here are a few examples:
1558 @item --listen=/gnu/var/daemon
1559 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1560 creating it if needed.
1562 @item --listen=localhost
1563 @cindex daemon, remote access
1564 @cindex remote access to the daemon
1565 @cindex daemon, cluster setup
1566 @cindex clusters, daemon setup
1567 Listen for TCP connections on the network interface corresponding to
1568 @code{localhost}, on port 44146.
1570 @item --listen=128.0.0.42:1234
1571 Listen for TCP connections on the network interface corresponding to
1572 @code{128.0.0.42}, on port 1234.
1575 This option can be repeated multiple times, in which case
1576 @command{guix-daemon} accepts connections on all the specified
1577 endpoints. Users can tell client commands what endpoint to connect to
1578 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1579 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1582 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1583 @option{--listen=@var{host}} is suitable on local networks, such as
1584 clusters, where only trusted nodes may connect to the build daemon. In
1585 other cases where remote access to the daemon is needed, we recommend
1586 using Unix-domain sockets along with SSH.
1589 When @option{--listen} is omitted, @command{guix-daemon} listens for
1590 connections on the Unix-domain socket located at
1591 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1595 @node Application Setup
1596 @section Application Setup
1598 @cindex foreign distro
1599 When using Guix on top of GNU/Linux distribution other than Guix System---a
1600 so-called @dfn{foreign distro}---a few additional steps are needed to
1601 get everything in place. Here are some of them.
1605 @anchor{locales-and-locpath}
1606 @cindex locales, when not on Guix System
1608 @vindex GUIX_LOCPATH
1609 Packages installed @i{via} Guix will not use the locale data of the
1610 host system. Instead, you must first install one of the locale packages
1611 available with Guix and then define the @env{GUIX_LOCPATH} environment
1615 $ guix install glibc-locales
1616 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1619 Note that the @code{glibc-locales} package contains data for all the
1620 locales supported by the GNU@tie{}libc and weighs in at around
1621 917@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1622 limited to a few UTF-8 locales.
1624 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1625 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1626 Manual}). There are two important differences though:
1630 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1631 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1632 to make sure the programs of the foreign distro will not end up loading
1633 incompatible locale data.
1636 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1637 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1638 should your Guix profile contain a mixture of programs linked against
1639 different libc version, each libc version will only try to load locale
1640 data in the right format.
1643 This is important because the locale data format used by different libc
1644 versions may be incompatible.
1646 @subsection Name Service Switch
1648 @cindex name service switch, glibc
1649 @cindex NSS (name service switch), glibc
1650 @cindex nscd (name service caching daemon)
1651 @cindex name service caching daemon (nscd)
1652 When using Guix on a foreign distro, we @emph{strongly recommend} that
1653 the system run the GNU C library's @dfn{name service cache daemon},
1654 @command{nscd}, which should be listening on the
1655 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1656 installed with Guix may fail to look up host names or user accounts, or
1657 may even crash. The next paragraphs explain why.
1659 @cindex @file{nsswitch.conf}
1660 The GNU C library implements a @dfn{name service switch} (NSS), which is
1661 an extensible mechanism for ``name lookups'' in general: host name
1662 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1663 The GNU C Library Reference Manual}).
1665 @cindex Network information service (NIS)
1666 @cindex NIS (Network information service)
1667 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1668 lookup implementations: for example, the @code{nss-mdns} plugin allow
1669 resolution of @code{.local} host names, the @code{nis} plugin allows
1670 user account lookup using the Network information service (NIS), and so
1671 on. These extra ``lookup services'' are configured system-wide in
1672 @file{/etc/nsswitch.conf}, and all the programs running on the system
1673 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1676 When they perform a name lookup---for instance by calling the
1677 @code{getaddrinfo} function in C---applications first try to connect to
1678 the nscd; on success, nscd performs name lookups on their behalf. If
1679 the nscd is not running, then they perform the name lookup by
1680 themselves, by loading the name lookup services into their own address
1681 space and running it. These name lookup services---the
1682 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1683 the host system's C library, rather than from the C library the
1684 application is linked against (the C library coming from Guix).
1686 And this is where the problem is: if your application is linked against
1687 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1688 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1689 likely crash or have its name lookups fail unexpectedly.
1691 Running @command{nscd} on the system, among other advantages, eliminates
1692 this binary incompatibility problem because those @code{libnss_*.so}
1693 files are loaded in the @command{nscd} process, not in applications
1696 @subsection X11 Fonts
1699 The majority of graphical applications use Fontconfig to locate and
1700 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1701 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1702 by default. Thus, to allow graphical applications installed with Guix
1703 to display fonts, you have to install fonts with Guix as well.
1704 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1705 @code{font-gnu-freefont}.
1707 @cindex @code{fc-cache}
1709 Once you have installed or removed fonts, or when you notice an
1710 application that does not find fonts, you may need to install Fontconfig
1711 and to force an update of its font cache by running:
1714 guix install fontconfig
1718 To display text written in Chinese languages, Japanese, or Korean in
1719 graphical applications, consider installing
1720 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1721 has multiple outputs, one per language family (@pxref{Packages with
1722 Multiple Outputs}). For instance, the following command installs fonts
1723 for Chinese languages:
1726 guix install font-adobe-source-han-sans:cn
1729 @cindex @code{xterm}
1730 Older programs such as @command{xterm} do not use Fontconfig and instead
1731 rely on server-side font rendering. Such programs require to specify a
1732 full name of a font using XLFD (X Logical Font Description), like this:
1735 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1738 To be able to use such full names for the TrueType fonts installed in
1739 your Guix profile, you need to extend the font path of the X server:
1741 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1742 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1744 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1747 @cindex @code{xlsfonts}
1748 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1749 to make sure your TrueType fonts are listed there.
1752 @subsection X.509 Certificates
1754 @cindex @code{nss-certs}
1755 The @code{nss-certs} package provides X.509 certificates, which allow
1756 programs to authenticate Web servers accessed over HTTPS.
1758 When using Guix on a foreign distro, you can install this package and
1759 define the relevant environment variables so that packages know where to
1760 look for certificates. @xref{X.509 Certificates}, for detailed
1763 @subsection Emacs Packages
1765 @cindex @code{emacs}
1766 When you install Emacs packages with Guix, the Elisp files are placed
1767 under the @file{share/emacs/site-lisp/} directory of the profile in
1768 which they are installed. The Elisp libraries are made available to
1769 Emacs through the @env{EMACSLOADPATH} environment variable, which is
1770 set when installing Emacs itself.
1772 Additionally, autoload definitions are automatically evaluated at the
1773 initialization of Emacs, by the Guix-specific
1774 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1775 want to avoid auto-loading the Emacs packages installed with Guix, you
1776 can do so by running Emacs with the @option{--no-site-file} option
1777 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1780 @node Upgrading Guix
1781 @section Upgrading Guix
1783 @cindex Upgrading Guix, on a foreign distro
1785 To upgrade Guix, run:
1791 @xref{Invoking guix pull}, for more information.
1793 @cindex upgrading Guix for the root user, on a foreign distro
1794 @cindex upgrading the Guix daemon, on a foreign distro
1795 @cindex @command{guix pull} for the root user, on a foreign distro
1797 On a foreign distro, you can upgrade the build daemon by running:
1804 followed by (assuming your distro uses the systemd service management
1808 systemctl restart guix-daemon.service
1811 On Guix System, upgrading the daemon is achieved by reconfiguring the
1812 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1816 @c *********************************************************************
1817 @node System Installation
1818 @chapter System Installation
1820 @cindex installing Guix System
1821 @cindex Guix System, installation
1822 This section explains how to install Guix System
1823 on a machine. Guix, as a package manager, can
1824 also be installed on top of a running GNU/Linux system,
1825 @pxref{Installation}.
1829 @c This paragraph is for people reading this from tty2 of the
1830 @c installation image.
1831 You are reading this documentation with an Info reader. For details on
1832 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1833 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1834 Info}. Hit @kbd{l} afterwards to come back here.
1836 Alternatively, run @command{info info} in another tty to keep the manual
1842 * Limitations:: What you can expect.
1843 * Hardware Considerations:: Supported hardware.
1844 * USB Stick and DVD Installation:: Preparing the installation medium.
1845 * Preparing for Installation:: Networking, partitioning, etc.
1846 * Guided Graphical Installation:: Easy graphical installation.
1847 * Manual Installation:: Manual installation for wizards.
1848 * After System Installation:: When installation succeeded.
1849 * Installing Guix in a VM:: Guix System playground.
1850 * Building the Installation Image:: How this comes to be.
1854 @section Limitations
1856 We consider Guix System to be ready for a wide range of ``desktop'' and server
1857 use cases. The reliability guarantees it provides---transactional upgrades
1858 and rollbacks, reproducibility---make it a solid foundation.
1860 Nevertheless, before you proceed with the installation, be aware of the
1861 following noteworthy limitations applicable to version @value{VERSION}:
1865 Support for the Logical Volume Manager (LVM) is missing.
1868 More and more system services are provided (@pxref{Services}), but some
1872 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1873 as well as a number of X11 window managers. However, KDE is currently
1877 More than a disclaimer, this is an invitation to report issues (and success
1878 stories!), and to join us in improving it. @xref{Contributing}, for more
1882 @node Hardware Considerations
1883 @section Hardware Considerations
1885 @cindex hardware support on Guix System
1886 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1887 builds around the kernel Linux-libre, which means that only hardware for
1888 which free software drivers and firmware exist is supported. Nowadays,
1889 a wide range of off-the-shelf hardware is supported on
1890 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1891 Ethernet controllers. Unfortunately, there are still areas where
1892 hardware vendors deny users control over their own computing, and such
1893 hardware is not supported on Guix System.
1895 @cindex WiFi, hardware support
1896 One of the main areas where free drivers or firmware are lacking is WiFi
1897 devices. WiFi devices known to work include those using Atheros chips
1898 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1899 driver, and those using Broadcom/AirForce chips (BCM43xx with
1900 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1901 Linux-libre driver. Free firmware exists for both and is available
1902 out-of-the-box on Guix System, as part of @code{%base-firmware}
1903 (@pxref{operating-system Reference, @code{firmware}}).
1905 @cindex RYF, Respects Your Freedom
1906 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1907 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1908 certification program for hardware products that respect your freedom
1909 and your privacy and ensure that you have control over your device. We
1910 encourage you to check the list of RYF-certified devices.
1912 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1913 web site. It contains a catalog of hardware devices with information
1914 about their support in GNU/Linux.
1917 @node USB Stick and DVD Installation
1918 @section USB Stick and DVD Installation
1920 An ISO-9660 installation image that can be written to a USB stick or
1921 burnt to a DVD can be downloaded from
1922 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz},
1923 where you can replace @code{x86_64-linux} with one of:
1927 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1930 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1933 @c start duplication of authentication part from ``Binary Installation''
1934 Make sure to download the associated @file{.sig} file and to verify the
1935 authenticity of the image against it, along these lines:
1938 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
1939 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
1942 If that command fails because you do not have the required public key,
1943 then run this command to import it:
1946 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1947 -qO - | gpg --import -
1951 and rerun the @code{gpg --verify} command.
1953 Take note that a warning like ``This key is not certified with a trusted
1954 signature!'' is normal.
1958 This image contains the tools necessary for an installation.
1959 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1961 @unnumberedsubsec Copying to a USB Stick
1963 To copy the image to a USB stick, follow these steps:
1967 Decompress the image using the @command{xz} command:
1970 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
1974 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1975 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1976 copy the image with:
1979 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX
1983 Access to @file{/dev/sdX} usually requires root privileges.
1986 @unnumberedsubsec Burning on a DVD
1988 To copy the image to a DVD, follow these steps:
1992 Decompress the image using the @command{xz} command:
1995 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
1999 Insert a blank DVD into your machine, and determine
2000 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2001 copy the image with:
2004 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2007 Access to @file{/dev/srX} usually requires root privileges.
2010 @unnumberedsubsec Booting
2012 Once this is done, you should be able to reboot the system and boot from
2013 the USB stick or DVD. The latter usually requires you to get in the
2014 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2015 In order to boot from Libreboot, switch to the command mode by pressing
2016 the @kbd{c} key and type @command{search_grub usb}.
2018 @xref{Installing Guix in a VM}, if, instead, you would like to install
2019 Guix System in a virtual machine (VM).
2022 @node Preparing for Installation
2023 @section Preparing for Installation
2025 Once you have booted, you can use the guided graphical installer, which makes
2026 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2027 if you are already familiar with GNU/Linux and if you want more control than
2028 what the graphical installer provides, you can choose the ``manual''
2029 installation process (@pxref{Manual Installation}).
2031 The graphical installer is available on TTY1. You can obtain root shells on
2032 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2033 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2034 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2035 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2036 which allows you to select text with the left mouse button and to paste it
2037 with the middle button.
2040 Installation requires access to the Internet so that any missing
2041 dependencies of your system configuration can be downloaded. See the
2042 ``Networking'' section below.
2045 @node Guided Graphical Installation
2046 @section Guided Graphical Installation
2048 The graphical installer is a text-based user interface. It will guide you,
2049 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2051 The first dialog boxes allow you to set up the system as you use it during the
2052 installation: you can choose the language, keyboard layout, and set up
2053 networking, which will be used during the installation. The image below shows
2054 the networking dialog.
2056 @image{images/installer-network,5in,, networking setup with the graphical installer}
2058 Later steps allow you to partition your hard disk, as shown in the image
2059 below, to choose whether or not to use encrypted file systems, to enter the
2060 host name and root password, and to create an additional account, among other
2063 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2065 Note that, at any time, the installer allows you to exit the current
2066 installation step and resume at a previous step, as show in the image below.
2068 @image{images/installer-resume,5in,, resuming the installation process}
2070 Once you're done, the installer produces an operating system configuration and
2071 displays it (@pxref{Using the Configuration System}). At that point you can
2072 hit ``OK'' and installation will proceed. On success, you can reboot into the
2073 new system and enjoy. @xref{After System Installation}, for what's next!
2076 @node Manual Installation
2077 @section Manual Installation
2079 This section describes how you would ``manually'' install GNU@tie{}Guix System
2080 on your machine. This option requires familiarity with GNU/Linux, with the
2081 shell, and with common administration tools. If you think this is not for
2082 you, consider using the guided graphical installer (@pxref{Guided Graphical
2085 The installation system provides root shells on TTYs 3 to 6; press
2086 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2087 many common tools needed to install the system. But it is also a full-blown
2088 Guix System, which means that you can install additional packages, should you
2089 need it, using @command{guix package} (@pxref{Invoking guix package}).
2092 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2093 * Proceeding with the Installation:: Installing.
2096 @node Keyboard Layout and Networking and Partitioning
2097 @subsection Keyboard Layout, Networking, and Partitioning
2099 Before you can install the system, you may want to adjust the keyboard layout,
2100 set up networking, and partition your target hard disk. This section will
2101 guide you through this.
2103 @subsubsection Keyboard Layout
2105 @cindex keyboard layout
2106 The installation image uses the US qwerty keyboard layout. If you want
2107 to change it, you can use the @command{loadkeys} command. For example,
2108 the following command selects the Dvorak keyboard layout:
2114 See the files under @file{/run/current-system/profile/share/keymaps} for
2115 a list of available keyboard layouts. Run @command{man loadkeys} for
2118 @subsubsection Networking
2120 Run the following command to see what your network interfaces are called:
2127 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2133 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2134 Wired interfaces have a name starting with @samp{e}; for example, the
2135 interface corresponding to the first on-board Ethernet controller is
2136 called @samp{eno1}. Wireless interfaces have a name starting with
2137 @samp{w}, like @samp{w1p2s0}.
2140 @item Wired connection
2141 To configure a wired network run the following command, substituting
2142 @var{interface} with the name of the wired interface you want to use.
2145 ifconfig @var{interface} up
2149 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2152 ip link set @var{interface} up
2155 @item Wireless connection
2158 To configure wireless networking, you can create a configuration file
2159 for the @command{wpa_supplicant} configuration tool (its location is not
2160 important) using one of the available text editors such as
2164 nano wpa_supplicant.conf
2167 As an example, the following stanza can go to this file and will work
2168 for many wireless networks, provided you give the actual SSID and
2169 passphrase for the network you are connecting to:
2173 ssid="@var{my-ssid}"
2175 psk="the network's secret passphrase"
2179 Start the wireless service and run it in the background with the
2180 following command (substitute @var{interface} with the name of the
2181 network interface you want to use):
2184 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2187 Run @command{man wpa_supplicant} for more information.
2191 At this point, you need to acquire an IP address. On a network where IP
2192 addresses are automatically assigned @i{via} DHCP, you can run:
2195 dhclient -v @var{interface}
2198 Try to ping a server to see if networking is up and running:
2204 Setting up network access is almost always a requirement because the
2205 image does not contain all the software and tools that may be needed.
2207 @cindex proxy, during system installation
2208 If you need HTTP and HTTPS access to go through a proxy, run the
2212 herd set-http-proxy guix-daemon @var{URL}
2216 where @var{URL} is the proxy URL, for example
2217 @code{http://example.org:8118}.
2219 @cindex installing over SSH
2220 If you want to, you can continue the installation remotely by starting
2224 herd start ssh-daemon
2227 Make sure to either set a password with @command{passwd}, or configure
2228 OpenSSH public key authentication before logging in.
2230 @subsubsection Disk Partitioning
2232 Unless this has already been done, the next step is to partition, and
2233 then format the target partition(s).
2235 The installation image includes several partitioning tools, including
2236 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2237 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2238 the partition layout you want:
2244 If your disk uses the GUID Partition Table (GPT) format and you plan to
2245 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2246 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2249 @cindex EFI, installation
2250 @cindex UEFI, installation
2251 @cindex ESP, EFI system partition
2252 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2253 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2254 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2257 parted /dev/sda set 1 esp on
2261 @vindex grub-bootloader
2262 @vindex grub-efi-bootloader
2263 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2264 @file{/sys/firmware/efi} exists in the installation image, then you should
2265 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2266 Otherwise you should use the BIOS-based GRUB, known as
2267 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2271 Once you are done partitioning the target hard disk drive, you have to
2272 create a file system on the relevant partition(s)@footnote{Currently
2273 Guix System only supports ext4, btrfs, and JFS file systems. In particular,
2274 code that reads file system UUIDs and labels only works for these file system
2275 types.}. For the ESP, if you have one and assuming it is
2276 @file{/dev/sda1}, run:
2279 mkfs.fat -F32 /dev/sda1
2282 For the root file system, ext4 is the most widely used format. Other
2283 file systems, such as Btrfs, support compression, which is reported to
2284 nicely complement file deduplication that the daemon performs
2285 independently of the file system (@pxref{Invoking guix-daemon,
2288 Preferably, assign file systems a label so that you can easily and
2289 reliably refer to them in @code{file-system} declarations (@pxref{File
2290 Systems}). This is typically done using the @code{-L} option of
2291 @command{mkfs.ext4} and related commands. So, assuming the target root
2292 partition lives at @file{/dev/sda2}, a file system with the label
2293 @code{my-root} can be created with:
2296 mkfs.ext4 -L my-root /dev/sda2
2299 @cindex encrypted disk
2300 If you are instead planning to encrypt the root partition, you can use
2301 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2302 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2303 @code{man cryptsetup}} for more information). Assuming you want to
2304 store the root partition on @file{/dev/sda2}, the command sequence would
2305 be along these lines:
2308 cryptsetup luksFormat /dev/sda2
2309 cryptsetup open --type luks /dev/sda2 my-partition
2310 mkfs.ext4 -L my-root /dev/mapper/my-partition
2313 Once that is done, mount the target file system under @file{/mnt}
2314 with a command like (again, assuming @code{my-root} is the label of the
2318 mount LABEL=my-root /mnt
2321 Also mount any other file systems you would like to use on the target
2322 system relative to this path. If you have opted for @file{/boot/efi} as an
2323 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2324 found by @code{guix system init} afterwards.
2326 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2327 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2328 sure to initialize them with @command{mkswap}. Assuming you have one
2329 swap partition on @file{/dev/sda3}, you would run:
2336 Alternatively, you may use a swap file. For example, assuming that in
2337 the new system you want to use the file @file{/swapfile} as a swap file,
2338 you would run@footnote{This example will work for many types of file
2339 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2340 btrfs), the required steps may be different. For details, see the
2341 manual pages for @command{mkswap} and @command{swapon}.}:
2344 # This is 10 GiB of swap space. Adjust "count" to change the size.
2345 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2346 # For security, make the file readable and writable only by root.
2347 chmod 600 /mnt/swapfile
2348 mkswap /mnt/swapfile
2349 swapon /mnt/swapfile
2352 Note that if you have encrypted the root partition and created a swap
2353 file in its file system as described above, then the encryption also
2354 protects the swap file, just like any other file in that file system.
2356 @node Proceeding with the Installation
2357 @subsection Proceeding with the Installation
2359 With the target partitions ready and the target root mounted on
2360 @file{/mnt}, we're ready to go. First, run:
2363 herd start cow-store /mnt
2366 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2367 during the installation phase are written to the target disk on @file{/mnt}
2368 rather than kept in memory. This is necessary because the first phase of
2369 the @command{guix system init} command (see below) entails downloads or
2370 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2372 Next, you have to edit a file and
2373 provide the declaration of the operating system to be installed. To
2374 that end, the installation system comes with three text editors. We
2375 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2376 supports syntax highlighting and parentheses matching; other editors
2377 include GNU Zile (an Emacs clone), and
2378 nvi (a clone of the original BSD @command{vi} editor).
2379 We strongly recommend storing that file on the target root file system, say,
2380 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2381 configuration file once you have rebooted into the newly-installed system.
2383 @xref{Using the Configuration System}, for an overview of the
2384 configuration file. The example configurations discussed in that
2385 section are available under @file{/etc/configuration} in the
2386 installation image. Thus, to get started with a system configuration
2387 providing a graphical display server (a ``desktop'' system), you can run
2388 something along these lines:
2392 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2393 # nano /mnt/etc/config.scm
2396 You should pay attention to what your configuration file contains, and
2401 Make sure the @code{bootloader-configuration} form refers to the target
2402 you want to install GRUB on. It should mention @code{grub-bootloader} if
2403 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2404 for newer UEFI systems. For legacy systems, the @code{target} field
2405 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2406 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2407 currently mounted and a @code{file-system} entry is specified in your
2411 Be sure that your file system labels match the value of their respective
2412 @code{device} fields in your @code{file-system} configuration, assuming
2413 your @code{file-system} configuration uses the @code{file-system-label}
2414 procedure in its @code{device} field.
2417 If there are encrypted or RAID partitions, make sure to add a
2418 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2421 Once you are done preparing the configuration file, the new system must
2422 be initialized (remember that the target root file system is mounted
2426 guix system init /mnt/etc/config.scm /mnt
2430 This copies all the necessary files and installs GRUB on
2431 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2432 more information, @pxref{Invoking guix system}. This command may trigger
2433 downloads or builds of missing packages, which can take some time.
2435 Once that command has completed---and hopefully succeeded!---you can run
2436 @command{reboot} and boot into the new system. The @code{root} password
2437 in the new system is initially empty; other users' passwords need to be
2438 initialized by running the @command{passwd} command as @code{root},
2439 unless your configuration specifies otherwise
2440 (@pxref{user-account-password, user account passwords}).
2441 @xref{After System Installation}, for what's next!
2444 @node After System Installation
2445 @section After System Installation
2447 Success, you've now booted into Guix System! From then on, you can update the
2448 system whenever you want by running, say:
2452 sudo guix system reconfigure /etc/config.scm
2456 This builds a new system generation with the latest packages and services
2457 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2458 your system includes the latest security updates (@pxref{Security Updates}).
2460 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2462 @cindex sudo vs. @command{guix pull}
2463 Note that @command{sudo guix} runs your user's @command{guix} command and
2464 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2465 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2467 The difference matters here, because @command{guix pull} updates
2468 the @command{guix} command and package definitions only for the user it is ran
2469 as. This means that if you choose to use @command{guix system reconfigure} in
2470 root's login shell, you'll need to @command{guix pull} separately.
2473 Join us on @code{#guix} on the Freenode IRC network or on
2474 @email{guix-devel@@gnu.org} to share your experience!
2477 @node Installing Guix in a VM
2478 @section Installing Guix in a Virtual Machine
2480 @cindex virtual machine, Guix System installation
2481 @cindex virtual private server (VPS)
2482 @cindex VPS (virtual private server)
2483 If you'd like to install Guix System in a virtual machine (VM) or on a
2484 virtual private server (VPS) rather than on your beloved machine, this
2487 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2488 disk image, follow these steps:
2492 First, retrieve and decompress the Guix system installation image as
2493 described previously (@pxref{USB Stick and DVD Installation}).
2496 Create a disk image that will hold the installed system. To make a
2497 qcow2-formatted disk image, use the @command{qemu-img} command:
2500 qemu-img create -f qcow2 guix-system.img 50G
2503 The resulting file will be much smaller than 50 GB (typically less than
2504 1 MB), but it will grow as the virtualized storage device is filled up.
2507 Boot the USB installation image in an VM:
2510 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2511 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2512 -drive file=guix-system.img \
2513 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2516 @code{-enable-kvm} is optional, but significantly improves performance,
2517 @pxref{Running Guix in a VM}.
2520 You're now root in the VM, proceed with the installation process.
2521 @xref{Preparing for Installation}, and follow the instructions.
2524 Once installation is complete, you can boot the system that's on your
2525 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2528 @node Building the Installation Image
2529 @section Building the Installation Image
2531 @cindex installation image
2532 The installation image described above was built using the @command{guix
2533 system} command, specifically:
2536 guix system disk-image --file-system-type=iso9660 \
2537 gnu/system/install.scm
2540 Have a look at @file{gnu/system/install.scm} in the source tree,
2541 and see also @ref{Invoking guix system} for more information
2542 about the installation image.
2544 @section Building the Installation Image for ARM Boards
2546 Many ARM boards require a specific variant of the
2547 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2549 If you build a disk image and the bootloader is not available otherwise
2550 (on another boot drive etc), it's advisable to build an image that
2551 includes the bootloader, specifically:
2554 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2557 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2558 board, a list of possible boards will be printed.
2560 @c *********************************************************************
2561 @node Package Management
2562 @chapter Package Management
2565 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2566 remove software packages, without having to know about their build
2567 procedures or dependencies. Guix also goes beyond this obvious set of
2570 This chapter describes the main features of Guix, as well as the
2571 package management tools it provides. Along with the command-line
2572 interface described below (@pxref{Invoking guix package, @code{guix
2573 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2574 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2575 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2579 guix install emacs-guix
2583 * Features:: How Guix will make your life brighter.
2584 * Invoking guix package:: Package installation, removal, etc.
2585 * Substitutes:: Downloading pre-built binaries.
2586 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2587 * Invoking guix gc:: Running the garbage collector.
2588 * Invoking guix pull:: Fetching the latest Guix and distribution.
2589 * Channels:: Customizing the package collection.
2590 * Invoking guix time-machine:: Running an older revision of Guix.
2591 * Inferiors:: Interacting with another revision of Guix.
2592 * Invoking guix describe:: Display information about your Guix revision.
2593 * Invoking guix archive:: Exporting and importing store files.
2599 When using Guix, each package ends up in the @dfn{package store}, in its
2600 own directory---something that resembles
2601 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2603 Instead of referring to these directories, users have their own
2604 @dfn{profile}, which points to the packages that they actually want to
2605 use. These profiles are stored within each user's home directory, at
2606 @code{$HOME/.guix-profile}.
2608 For example, @code{alice} installs GCC 4.7.2. As a result,
2609 @file{/home/alice/.guix-profile/bin/gcc} points to
2610 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2611 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2612 simply continues to point to
2613 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2614 coexist on the same system without any interference.
2616 The @command{guix package} command is the central tool to manage
2617 packages (@pxref{Invoking guix package}). It operates on the per-user
2618 profiles, and can be used @emph{with normal user privileges}.
2620 @cindex transactions
2621 The command provides the obvious install, remove, and upgrade
2622 operations. Each invocation is actually a @emph{transaction}: either
2623 the specified operation succeeds, or nothing happens. Thus, if the
2624 @command{guix package} process is terminated during the transaction,
2625 or if a power outage occurs during the transaction, then the user's
2626 profile remains in its previous state, and remains usable.
2628 In addition, any package transaction may be @emph{rolled back}. So, if,
2629 for example, an upgrade installs a new version of a package that turns
2630 out to have a serious bug, users may roll back to the previous instance
2631 of their profile, which was known to work well. Similarly, the global
2632 system configuration on Guix is subject to
2633 transactional upgrades and roll-back
2634 (@pxref{Using the Configuration System}).
2636 All packages in the package store may be @emph{garbage-collected}.
2637 Guix can determine which packages are still referenced by user
2638 profiles, and remove those that are provably no longer referenced
2639 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2640 generations of their profile so that the packages they refer to can be
2643 @cindex reproducibility
2644 @cindex reproducible builds
2645 Guix takes a @dfn{purely functional} approach to package
2646 management, as described in the introduction (@pxref{Introduction}).
2647 Each @file{/gnu/store} package directory name contains a hash of all the
2648 inputs that were used to build that package---compiler, libraries, build
2649 scripts, etc. This direct correspondence allows users to make sure a
2650 given package installation matches the current state of their
2651 distribution. It also helps maximize @dfn{build reproducibility}:
2652 thanks to the isolated build environments that are used, a given build
2653 is likely to yield bit-identical files when performed on different
2654 machines (@pxref{Invoking guix-daemon, container}).
2657 This foundation allows Guix to support @dfn{transparent binary/source
2658 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2659 available from an external source---a @dfn{substitute}, Guix just
2660 downloads it and unpacks it;
2661 otherwise, it builds the package from source, locally
2662 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2663 reproducible, users do not have to trust servers that provide
2664 substitutes: they can force a local build and @emph{challenge} providers
2665 (@pxref{Invoking guix challenge}).
2667 Control over the build environment is a feature that is also useful for
2668 developers. The @command{guix environment} command allows developers of
2669 a package to quickly set up the right development environment for their
2670 package, without having to manually install the dependencies of the
2671 package into their profile (@pxref{Invoking guix environment}).
2673 @cindex replication, of software environments
2674 @cindex provenance tracking, of software artifacts
2675 All of Guix and its package definitions is version-controlled, and
2676 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2677 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2678 Guix instance on a different machine or at a later point in time, which in
2679 turn allows you to @emph{replicate complete software environments}, while
2680 retaining precise @dfn{provenance tracking} of the software.
2682 @node Invoking guix package
2683 @section Invoking @command{guix package}
2685 @cindex installing packages
2686 @cindex removing packages
2687 @cindex package installation
2688 @cindex package removal
2689 The @command{guix package} command is the tool that allows users to
2690 install, upgrade, and remove packages, as well as rolling back to
2691 previous configurations. It operates only on the user's own profile,
2692 and works with normal user privileges (@pxref{Features}). Its syntax
2696 guix package @var{options}
2699 @cindex transactions
2700 Primarily, @var{options} specifies the operations to be performed during
2701 the transaction. Upon completion, a new profile is created, but
2702 previous @dfn{generations} of the profile remain available, should the user
2705 For example, to remove @code{lua} and install @code{guile} and
2706 @code{guile-cairo} in a single transaction:
2709 guix package -r lua -i guile guile-cairo
2712 @cindex aliases, for @command{guix package}
2713 For your convenience, we also provide the following aliases:
2717 @command{guix search} is an alias for @command{guix package -s},
2719 @command{guix install} is an alias for @command{guix package -i},
2721 @command{guix remove} is an alias for @command{guix package -r},
2723 @command{guix upgrade} is an alias for @command{guix package -u},
2725 and @command{guix show} is an alias for @command{guix package --show=}.
2728 These aliases are less expressive than @command{guix package} and provide
2729 fewer options, so in some cases you'll probably want to use @command{guix
2732 @command{guix package} also supports a @dfn{declarative approach}
2733 whereby the user specifies the exact set of packages to be available and
2734 passes it @i{via} the @option{--manifest} option
2735 (@pxref{profile-manifest, @option{--manifest}}).
2738 For each user, a symlink to the user's default profile is automatically
2739 created in @file{$HOME/.guix-profile}. This symlink always points to the
2740 current generation of the user's default profile. Thus, users can add
2741 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
2742 variable, and so on.
2743 @cindex search paths
2744 If you are not using Guix System, consider adding the
2745 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2746 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2747 shells get all the right environment variable definitions:
2750 GUIX_PROFILE="$HOME/.guix-profile" ; \
2751 source "$HOME/.guix-profile/etc/profile"
2754 In a multi-user setup, user profiles are stored in a place registered as
2755 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2756 to (@pxref{Invoking guix gc}). That directory is normally
2757 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2758 @var{localstatedir} is the value passed to @code{configure} as
2759 @option{--localstatedir}, and @var{user} is the user name. The
2760 @file{per-user} directory is created when @command{guix-daemon} is
2761 started, and the @var{user} sub-directory is created by @command{guix
2764 The @var{options} can be among the following:
2768 @item --install=@var{package} @dots{}
2769 @itemx -i @var{package} @dots{}
2770 Install the specified @var{package}s.
2772 Each @var{package} may specify either a simple package name, such as
2773 @code{guile}, or a package name followed by an at-sign and version number,
2774 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2775 case, the newest version prefixed by @code{1.8} is selected).
2777 If no version number is specified, the
2778 newest available version will be selected. In addition, @var{package}
2779 may contain a colon, followed by the name of one of the outputs of the
2780 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2781 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2782 name (and optionally version) are searched for among the GNU
2783 distribution modules (@pxref{Package Modules}).
2785 @cindex propagated inputs
2786 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2787 that automatically get installed along with the required package
2788 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2789 @code{package} objects}, for information about propagated inputs in
2790 package definitions).
2792 @anchor{package-cmd-propagated-inputs}
2793 An example is the GNU MPC library: its C header files refer to those of
2794 the GNU MPFR library, which in turn refer to those of the GMP library.
2795 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2796 in the profile; removing MPC also removes MPFR and GMP---unless they had
2797 also been explicitly installed by the user.
2799 Besides, packages sometimes rely on the definition of environment
2800 variables for their search paths (see explanation of
2801 @option{--search-paths} below). Any missing or possibly incorrect
2802 environment variable definitions are reported here.
2804 @item --install-from-expression=@var{exp}
2806 Install the package @var{exp} evaluates to.
2808 @var{exp} must be a Scheme expression that evaluates to a
2809 @code{<package>} object. This option is notably useful to disambiguate
2810 between same-named variants of a package, with expressions such as
2811 @code{(@@ (gnu packages base) guile-final)}.
2813 Note that this option installs the first output of the specified
2814 package, which may be insufficient when needing a specific output of a
2815 multiple-output package.
2817 @item --install-from-file=@var{file}
2818 @itemx -f @var{file}
2819 Install the package that the code within @var{file} evaluates to.
2821 As an example, @var{file} might contain a definition like this
2822 (@pxref{Defining Packages}):
2825 @include package-hello.scm
2828 Developers may find it useful to include such a @file{guix.scm} file
2829 in the root of their project source tree that can be used to test
2830 development snapshots and create reproducible development environments
2831 (@pxref{Invoking guix environment}).
2833 The @var{file} may also contain a JSON representation of one or more
2834 package definitions. Running @code{guix package -f} on
2835 @file{hello.json} with the following contents would result in installing
2836 the package @code{greeter} after building @code{myhello}:
2839 @verbatiminclude package-hello.json
2842 @item --remove=@var{package} @dots{}
2843 @itemx -r @var{package} @dots{}
2844 Remove the specified @var{package}s.
2846 As for @option{--install}, each @var{package} may specify a version number
2847 and/or output name in addition to the package name. For instance,
2848 @samp{-r glibc:debug} would remove the @code{debug} output of
2851 @item --upgrade[=@var{regexp} @dots{}]
2852 @itemx -u [@var{regexp} @dots{}]
2853 @cindex upgrading packages
2854 Upgrade all the installed packages. If one or more @var{regexp}s are
2855 specified, upgrade only installed packages whose name matches a
2856 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
2858 Note that this upgrades package to the latest version of packages found
2859 in the distribution currently installed. To update your distribution,
2860 you should regularly run @command{guix pull} (@pxref{Invoking guix
2863 @item --do-not-upgrade[=@var{regexp} @dots{}]
2864 When used together with the @option{--upgrade} option, do @emph{not}
2865 upgrade any packages whose name matches a @var{regexp}. For example, to
2866 upgrade all packages in the current profile except those containing the
2867 substring ``emacs'':
2870 $ guix package --upgrade . --do-not-upgrade emacs
2873 @item @anchor{profile-manifest}--manifest=@var{file}
2874 @itemx -m @var{file}
2875 @cindex profile declaration
2876 @cindex profile manifest
2877 Create a new generation of the profile from the manifest object
2878 returned by the Scheme code in @var{file}. This option can be repeated
2879 several times, in which case the manifests are concatenated.
2881 This allows you to @emph{declare} the profile's contents rather than
2882 constructing it through a sequence of @option{--install} and similar
2883 commands. The advantage is that @var{file} can be put under version
2884 control, copied to different machines to reproduce the same profile, and
2887 @c FIXME: Add reference to (guix profile) documentation when available.
2888 @var{file} must return a @dfn{manifest} object, which is roughly a list
2891 @findex packages->manifest
2893 (use-package-modules guile emacs)
2898 ;; Use a specific package output.
2899 (list guile-2.0 "debug")))
2902 @findex specifications->manifest
2903 In this example we have to know which modules define the @code{emacs}
2904 and @code{guile-2.0} variables to provide the right
2905 @code{use-package-modules} line, which can be cumbersome. We can
2906 instead provide regular package specifications and let
2907 @code{specifications->manifest} look up the corresponding package
2911 (specifications->manifest
2912 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2916 @cindex rolling back
2917 @cindex undoing transactions
2918 @cindex transactions, undoing
2919 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2920 the last transaction.
2922 When combined with options such as @option{--install}, roll back occurs
2923 before any other actions.
2925 When rolling back from the first generation that actually contains
2926 installed packages, the profile is made to point to the @dfn{zeroth
2927 generation}, which contains no files apart from its own metadata.
2929 After having rolled back, installing, removing, or upgrading packages
2930 overwrites previous future generations. Thus, the history of the
2931 generations in a profile is always linear.
2933 @item --switch-generation=@var{pattern}
2934 @itemx -S @var{pattern}
2936 Switch to a particular generation defined by @var{pattern}.
2938 @var{pattern} may be either a generation number or a number prefixed
2939 with ``+'' or ``-''. The latter means: move forward/backward by a
2940 specified number of generations. For example, if you want to return to
2941 the latest generation after @option{--roll-back}, use
2942 @option{--switch-generation=+1}.
2944 The difference between @option{--roll-back} and
2945 @option{--switch-generation=-1} is that @option{--switch-generation} will
2946 not make a zeroth generation, so if a specified generation does not
2947 exist, the current generation will not be changed.
2949 @item --search-paths[=@var{kind}]
2950 @cindex search paths
2951 Report environment variable definitions, in Bash syntax, that may be
2952 needed in order to use the set of installed packages. These environment
2953 variables are used to specify @dfn{search paths} for files used by some
2954 of the installed packages.
2956 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
2957 environment variables to be defined so it can look for headers and
2958 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2959 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2960 library are installed in the profile, then @option{--search-paths} will
2961 suggest setting these variables to @file{@var{profile}/include} and
2962 @file{@var{profile}/lib}, respectively.
2964 The typical use case is to define these environment variables in the
2968 $ eval `guix package --search-paths`
2971 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2972 meaning that the returned environment variable definitions will either
2973 be exact settings, or prefixes or suffixes of the current value of these
2974 variables. When omitted, @var{kind} defaults to @code{exact}.
2976 This option can also be used to compute the @emph{combined} search paths
2977 of several profiles. Consider this example:
2980 $ guix package -p foo -i guile
2981 $ guix package -p bar -i guile-json
2982 $ guix package -p foo -p bar --search-paths
2985 The last command above reports about the @env{GUILE_LOAD_PATH}
2986 variable, even though, taken individually, neither @file{foo} nor
2987 @file{bar} would lead to that recommendation.
2990 @item --profile=@var{profile}
2991 @itemx -p @var{profile}
2992 Use @var{profile} instead of the user's default profile.
2994 @var{profile} must be the name of a file that will be created upon
2995 completion. Concretely, @var{profile} will be a mere symbolic link
2996 (``symlink'') pointing to the actual profile where packages are
3000 $ guix install hello -p ~/code/my-profile
3002 $ ~/code/my-profile/bin/hello
3006 All it takes to get rid of the profile is to remove this symlink and its
3007 siblings that point to specific generations:
3010 $ rm ~/code/my-profile ~/code/my-profile-*-link
3013 @item --list-profiles
3014 List all the user's profiles:
3017 $ guix package --list-profiles
3018 /home/charlie/.guix-profile
3019 /home/charlie/code/my-profile
3020 /home/charlie/code/devel-profile
3021 /home/charlie/tmp/test
3024 When running as root, list all the profiles of all the users.
3026 @cindex collisions, in a profile
3027 @cindex colliding packages in profiles
3028 @cindex profile collisions
3029 @item --allow-collisions
3030 Allow colliding packages in the new profile. Use at your own risk!
3032 By default, @command{guix package} reports as an error @dfn{collisions}
3033 in the profile. Collisions happen when two or more different versions
3034 or variants of a given package end up in the profile.
3037 Use the bootstrap Guile to build the profile. This option is only
3038 useful to distribution developers.
3042 In addition to these actions, @command{guix package} supports the
3043 following options to query the current state of a profile, or the
3044 availability of packages:
3048 @item --search=@var{regexp}
3049 @itemx -s @var{regexp}
3050 @anchor{guix-search}
3051 @cindex searching for packages
3052 List the available packages whose name, synopsis, or description matches
3053 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3054 Print all the metadata of matching packages in
3055 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3056 GNU recutils manual}).
3058 This allows specific fields to be extracted using the @command{recsel}
3059 command, for instance:
3062 $ guix package -s malloc | recsel -p name,version,relevance
3076 Similarly, to show the name of all the packages available under the
3077 terms of the GNU@tie{}LGPL version 3:
3080 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3087 It is also possible to refine search results using several @code{-s} flags to
3088 @command{guix package}, or several arguments to @command{guix search}. For
3089 example, the following command returns a list of board games (this time using
3090 the @command{guix search} alias):
3093 $ guix search '\<board\>' game | recsel -p name
3098 If we were to omit @code{-s game}, we would also get software packages
3099 that deal with printed circuit boards; removing the angle brackets
3100 around @code{board} would further add packages that have to do with
3103 And now for a more elaborate example. The following command searches
3104 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3105 libraries, and prints the name and synopsis of the matching packages:
3108 $ guix search crypto library | \
3109 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3113 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3114 information on @dfn{selection expressions} for @code{recsel -e}.
3116 @item --show=@var{package}
3117 Show details about @var{package}, taken from the list of available packages, in
3118 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3122 $ guix package --show=python | recsel -p name,version
3130 You may also specify the full name of a package to only get details about a
3131 specific version of it (this time using the @command{guix show} alias):
3133 $ guix show python@@3.4 | recsel -p name,version
3140 @item --list-installed[=@var{regexp}]
3141 @itemx -I [@var{regexp}]
3142 List the currently installed packages in the specified profile, with the
3143 most recently installed packages shown last. When @var{regexp} is
3144 specified, list only installed packages whose name matches @var{regexp}.
3146 For each installed package, print the following items, separated by
3147 tabs: the package name, its version string, the part of the package that
3148 is installed (for instance, @code{out} for the default output,
3149 @code{include} for its headers, etc.), and the path of this package in
3152 @item --list-available[=@var{regexp}]
3153 @itemx -A [@var{regexp}]
3154 List packages currently available in the distribution for this system
3155 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3156 available packages whose name matches @var{regexp}.
3158 For each package, print the following items separated by tabs: its name,
3159 its version string, the parts of the package (@pxref{Packages with
3160 Multiple Outputs}), and the source location of its definition.
3162 @item --list-generations[=@var{pattern}]
3163 @itemx -l [@var{pattern}]
3165 Return a list of generations along with their creation dates; for each
3166 generation, show the installed packages, with the most recently
3167 installed packages shown last. Note that the zeroth generation is never
3170 For each installed package, print the following items, separated by
3171 tabs: the name of a package, its version string, the part of the package
3172 that is installed (@pxref{Packages with Multiple Outputs}), and the
3173 location of this package in the store.
3175 When @var{pattern} is used, the command returns only matching
3176 generations. Valid patterns include:
3179 @item @emph{Integers and comma-separated integers}. Both patterns denote
3180 generation numbers. For instance, @option{--list-generations=1} returns
3183 And @option{--list-generations=1,8,2} outputs three generations in the
3184 specified order. Neither spaces nor trailing commas are allowed.
3186 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3187 specified generations and everything in between. Note that the start of
3188 a range must be smaller than its end.
3190 It is also possible to omit the endpoint. For example,
3191 @option{--list-generations=2..}, returns all generations starting from the
3194 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3195 or months by passing an integer along with the first letter of the
3196 duration. For example, @option{--list-generations=20d} lists generations
3197 that are up to 20 days old.
3200 @item --delete-generations[=@var{pattern}]
3201 @itemx -d [@var{pattern}]
3202 When @var{pattern} is omitted, delete all generations except the current
3205 This command accepts the same patterns as @option{--list-generations}.
3206 When @var{pattern} is specified, delete the matching generations. When
3207 @var{pattern} specifies a duration, generations @emph{older} than the
3208 specified duration match. For instance, @option{--delete-generations=1m}
3209 deletes generations that are more than one month old.
3211 If the current generation matches, it is @emph{not} deleted. Also, the
3212 zeroth generation is never deleted.
3214 Note that deleting generations prevents rolling back to them.
3215 Consequently, this command must be used with care.
3219 Finally, since @command{guix package} may actually start build
3220 processes, it supports all the common build options (@pxref{Common Build
3221 Options}). It also supports package transformation options, such as
3222 @option{--with-source} (@pxref{Package Transformation Options}).
3223 However, note that package transformations are lost when upgrading; to
3224 preserve transformations across upgrades, you should define your own
3225 package variant in a Guile module and add it to @env{GUIX_PACKAGE_PATH}
3226 (@pxref{Defining Packages}).
3229 @section Substitutes
3232 @cindex pre-built binaries
3233 Guix supports transparent source/binary deployment, which means that it
3234 can either build things locally, or download pre-built items from a
3235 server, or both. We call these pre-built items @dfn{substitutes}---they
3236 are substitutes for local build results. In many cases, downloading a
3237 substitute is much faster than building things locally.
3239 Substitutes can be anything resulting from a derivation build
3240 (@pxref{Derivations}). Of course, in the common case, they are
3241 pre-built package binaries, but source tarballs, for instance, which
3242 also result from derivation builds, can be available as substitutes.
3245 * Official Substitute Server:: One particular source of substitutes.
3246 * Substitute Server Authorization:: How to enable or disable substitutes.
3247 * Substitute Authentication:: How Guix verifies substitutes.
3248 * Proxy Settings:: How to get substitutes via proxy.
3249 * Substitution Failure:: What happens when substitution fails.
3250 * On Trusting Binaries:: How can you trust that binary blob?
3253 @node Official Substitute Server
3254 @subsection Official Substitute Server
3257 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3258 that builds packages from Guix continuously for some
3259 architectures, and makes them available as substitutes. This is the
3260 default source of substitutes; it can be overridden by passing the
3261 @option{--substitute-urls} option either to @command{guix-daemon}
3262 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3263 or to client tools such as @command{guix package}
3264 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3267 Substitute URLs can be either HTTP or HTTPS.
3268 HTTPS is recommended because communications are encrypted; conversely,
3269 using HTTP makes all communications visible to an eavesdropper, who
3270 could use the information gathered to determine, for instance, whether
3271 your system has unpatched security vulnerabilities.
3273 Substitutes from the official build farm are enabled by default when
3274 using Guix System (@pxref{GNU Distribution}). However,
3275 they are disabled by default when using Guix on a foreign distribution,
3276 unless you have explicitly enabled them via one of the recommended
3277 installation steps (@pxref{Installation}). The following paragraphs
3278 describe how to enable or disable substitutes for the official build
3279 farm; the same procedure can also be used to enable substitutes for any
3280 other substitute server.
3282 @node Substitute Server Authorization
3283 @subsection Substitute Server Authorization
3286 @cindex substitutes, authorization thereof
3287 @cindex access control list (ACL), for substitutes
3288 @cindex ACL (access control list), for substitutes
3289 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3291 must add its public key to the access control list (ACL) of archive
3292 imports, using the @command{guix archive} command (@pxref{Invoking guix
3293 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3294 be compromised and to serve genuine substitutes.
3296 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3297 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3298 the installation prefix of Guix. If you installed Guix from source,
3299 make sure you checked the GPG signature of
3300 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3301 Then, you can run something like this:
3304 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3307 Once this is in place, the output of a command like @code{guix build}
3308 should change from something like:
3311 $ guix build emacs --dry-run
3312 The following derivations would be built:
3313 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3314 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3315 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3316 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3324 $ guix build emacs --dry-run
3325 112.3 MB would be downloaded:
3326 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3327 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3328 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3329 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3334 The text changed from ``The following derivations would be built'' to
3335 ``112.3 MB would be downloaded''. This indicates that substitutes from
3336 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3337 possible, for future builds.
3339 @cindex substitutes, how to disable
3340 The substitute mechanism can be disabled globally by running
3341 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
3342 guix-daemon}). It can also be disabled temporarily by passing the
3343 @option{--no-substitutes} option to @command{guix package},
3344 @command{guix build}, and other command-line tools.
3346 @node Substitute Authentication
3347 @subsection Substitute Authentication
3349 @cindex digital signatures
3350 Guix detects and raises an error when attempting to use a substitute
3351 that has been tampered with. Likewise, it ignores substitutes that are
3352 not signed, or that are not signed by one of the keys listed in the ACL.
3354 There is one exception though: if an unauthorized server provides
3355 substitutes that are @emph{bit-for-bit identical} to those provided by
3356 an authorized server, then the unauthorized server becomes eligible for
3357 downloads. For example, assume we have chosen two substitute servers
3361 --substitute-urls="https://a.example.org https://b.example.org"
3365 @cindex reproducible builds
3366 If the ACL contains only the key for @samp{b.example.org}, and if
3367 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
3368 then Guix will download substitutes from @samp{a.example.org} because it
3369 comes first in the list and can be considered a mirror of
3370 @samp{b.example.org}. In practice, independent build machines usually
3371 produce the same binaries, thanks to bit-reproducible builds (see
3374 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3375 (in other words, the server is not authenticated), contrary to what
3376 HTTPS clients such as Web browsers usually do. This is because Guix
3377 authenticates substitute information itself, as explained above, which
3378 is what we care about (whereas X.509 certificates are about
3379 authenticating bindings between domain names and public keys).
3381 @node Proxy Settings
3382 @subsection Proxy Settings
3386 Substitutes are downloaded over HTTP or HTTPS. The @env{http_proxy} and
3387 @env{https_proxy} environment variables can be set in the environment of
3388 @command{guix-daemon} and are honored for downloads of substitutes.
3389 Note that the value of those environment variables in the environment
3390 where @command{guix build}, @command{guix package}, and other client
3391 commands are run has @emph{absolutely no effect}.
3393 @node Substitution Failure
3394 @subsection Substitution Failure
3396 Even when a substitute for a derivation is available, sometimes the
3397 substitution attempt will fail. This can happen for a variety of
3398 reasons: the substitute server might be offline, the substitute may
3399 recently have been deleted, the connection might have been interrupted,
3402 When substitutes are enabled and a substitute for a derivation is
3403 available, but the substitution attempt fails, Guix will attempt to
3404 build the derivation locally depending on whether or not
3405 @option{--fallback} was given (@pxref{fallback-option,, common build
3406 option @option{--fallback}}). Specifically, if @option{--fallback} was
3407 omitted, then no local build will be performed, and the derivation is
3408 considered to have failed. However, if @option{--fallback} was given,
3409 then Guix will attempt to build the derivation locally, and the success
3410 or failure of the derivation depends on the success or failure of the
3411 local build. Note that when substitutes are disabled or no substitute
3412 is available for the derivation in question, a local build will
3413 @emph{always} be performed, regardless of whether or not
3414 @option{--fallback} was given.
3416 To get an idea of how many substitutes are available right now, you can
3417 try running the @command{guix weather} command (@pxref{Invoking guix
3418 weather}). This command provides statistics on the substitutes provided
3421 @node On Trusting Binaries
3422 @subsection On Trusting Binaries
3424 @cindex trust, of pre-built binaries
3425 Today, each individual's control over their own computing is at the
3426 mercy of institutions, corporations, and groups with enough power and
3427 determination to subvert the computing infrastructure and exploit its
3428 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3429 convenient, we encourage users to also build on their own, or even run
3430 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3431 interesting target. One way to help is by publishing the software you
3432 build using @command{guix publish} so that others have one more choice
3433 of server to download substitutes from (@pxref{Invoking guix publish}).
3435 Guix has the foundations to maximize build reproducibility
3436 (@pxref{Features}). In most cases, independent builds of a given
3437 package or derivation should yield bit-identical results. Thus, through
3438 a diverse set of independent package builds, we can strengthen the
3439 integrity of our systems. The @command{guix challenge} command aims to
3440 help users assess substitute servers, and to assist developers in
3441 finding out about non-deterministic package builds (@pxref{Invoking guix
3442 challenge}). Similarly, the @option{--check} option of @command{guix
3443 build} allows users to check whether previously-installed substitutes
3444 are genuine by rebuilding them locally (@pxref{build-check,
3445 @command{guix build --check}}).
3447 In the future, we want Guix to have support to publish and retrieve
3448 binaries to/from other users, in a peer-to-peer fashion. If you would
3449 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3451 @node Packages with Multiple Outputs
3452 @section Packages with Multiple Outputs
3454 @cindex multiple-output packages
3455 @cindex package outputs
3458 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3459 source package leads to exactly one directory in the store. When running
3460 @command{guix install glibc}, one installs the default output of the
3461 GNU libc package; the default output is called @code{out}, but its name
3462 can be omitted as shown in this command. In this particular case, the
3463 default output of @code{glibc} contains all the C header files, shared
3464 libraries, static libraries, Info documentation, and other supporting
3467 Sometimes it is more appropriate to separate the various types of files
3468 produced from a single source package into separate outputs. For
3469 instance, the GLib C library (used by GTK+ and related packages)
3470 installs more than 20 MiB of reference documentation as HTML pages.
3471 To save space for users who do not need it, the documentation goes to a
3472 separate output, called @code{doc}. To install the main GLib output,
3473 which contains everything but the documentation, one would run:
3479 @cindex documentation
3480 The command to install its documentation is:
3483 guix install glib:doc
3486 Some packages install programs with different ``dependency footprints''.
3487 For instance, the WordNet package installs both command-line tools and
3488 graphical user interfaces (GUIs). The former depend solely on the C
3489 library, whereas the latter depend on Tcl/Tk and the underlying X
3490 libraries. In this case, we leave the command-line tools in the default
3491 output, whereas the GUIs are in a separate output. This allows users
3492 who do not need the GUIs to save space. The @command{guix size} command
3493 can help find out about such situations (@pxref{Invoking guix size}).
3494 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3496 There are several such multiple-output packages in the GNU distribution.
3497 Other conventional output names include @code{lib} for libraries and
3498 possibly header files, @code{bin} for stand-alone programs, and
3499 @code{debug} for debugging information (@pxref{Installing Debugging
3500 Files}). The outputs of a packages are listed in the third column of
3501 the output of @command{guix package --list-available} (@pxref{Invoking
3505 @node Invoking guix gc
3506 @section Invoking @command{guix gc}
3508 @cindex garbage collector
3510 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3511 The @command{guix gc} command allows users to explicitly run the garbage
3512 collector to reclaim space from the @file{/gnu/store} directory. It is
3513 the @emph{only} way to remove files from @file{/gnu/store}---removing
3514 files or directories manually may break it beyond repair!
3517 @cindex garbage collector roots
3518 The garbage collector has a set of known @dfn{roots}: any file under
3519 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3520 cannot be deleted; any other file is considered @dfn{dead} and may be
3521 deleted. The set of garbage collector roots (``GC roots'' for short)
3522 includes default user profiles; by default, the symlinks under
3523 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3524 added with @command{guix build --root}, for example (@pxref{Invoking
3525 guix build}). The @command{guix gc --list-roots} command lists them.
3527 Prior to running @code{guix gc --collect-garbage} to make space, it is
3528 often useful to remove old generations from user profiles; that way, old
3529 package builds referenced by those generations can be reclaimed. This
3530 is achieved by running @code{guix package --delete-generations}
3531 (@pxref{Invoking guix package}).
3533 Our recommendation is to run a garbage collection periodically, or when
3534 you are short on disk space. For instance, to guarantee that at least
3535 5@tie{}GB are available on your disk, simply run:
3541 It is perfectly safe to run as a non-interactive periodic job
3542 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3543 Running @command{guix gc} with no arguments will collect as
3544 much garbage as it can, but that is often inconvenient: you may find
3545 yourself having to rebuild or re-download software that is ``dead'' from
3546 the GC viewpoint but that is necessary to build other pieces of
3547 software---e.g., the compiler tool chain.
3549 The @command{guix gc} command has three modes of operation: it can be
3550 used to garbage-collect any dead files (the default), to delete specific
3551 files (the @option{--delete} option), to print garbage-collector
3552 information, or for more advanced queries. The garbage collection
3553 options are as follows:
3556 @item --collect-garbage[=@var{min}]
3557 @itemx -C [@var{min}]
3558 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3559 sub-directories. This is the default operation when no option is
3562 When @var{min} is given, stop once @var{min} bytes have been collected.
3563 @var{min} may be a number of bytes, or it may include a unit as a
3564 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3565 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3567 When @var{min} is omitted, collect all the garbage.
3569 @item --free-space=@var{free}
3570 @itemx -F @var{free}
3571 Collect garbage until @var{free} space is available under
3572 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3573 as @code{500MiB}, as described above.
3575 When @var{free} or more is already available in @file{/gnu/store}, do
3576 nothing and exit immediately.
3578 @item --delete-generations[=@var{duration}]
3579 @itemx -d [@var{duration}]
3580 Before starting the garbage collection process, delete all the generations
3581 older than @var{duration}, for all the user profiles; when run as root, this
3582 applies to all the profiles @emph{of all the users}.
3584 For example, this command deletes all the generations of all your profiles
3585 that are older than 2 months (except generations that are current), and then
3586 proceeds to free space until at least 10 GiB are available:
3589 guix gc -d 2m -F 10G
3594 Attempt to delete all the store files and directories specified as
3595 arguments. This fails if some of the files are not in the store, or if
3596 they are still live.
3598 @item --list-failures
3599 List store items corresponding to cached build failures.
3601 This prints nothing unless the daemon was started with
3602 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3603 @option{--cache-failures}}).
3606 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3610 List store items in use by currently running processes. These store
3611 items are effectively considered GC roots: they cannot be deleted.
3613 @item --clear-failures
3614 Remove the specified store items from the failed-build cache.
3616 Again, this option only makes sense when the daemon is started with
3617 @option{--cache-failures}. Otherwise, it does nothing.
3620 Show the list of dead files and directories still present in the
3621 store---i.e., files and directories no longer reachable from any root.
3624 Show the list of live store files and directories.
3628 In addition, the references among existing store files can be queried:
3634 @cindex package dependencies
3635 List the references (respectively, the referrers) of store files given
3641 List the requisites of the store files passed as arguments. Requisites
3642 include the store files themselves, their references, and the references
3643 of these, recursively. In other words, the returned list is the
3644 @dfn{transitive closure} of the store files.
3646 @xref{Invoking guix size}, for a tool to profile the size of the closure
3647 of an element. @xref{Invoking guix graph}, for a tool to visualize
3648 the graph of references.
3652 Return the derivation(s) leading to the given store items
3653 (@pxref{Derivations}).
3655 For example, this command:
3658 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3662 returns the @file{.drv} file(s) leading to the @code{emacs} package
3663 installed in your profile.
3665 Note that there may be zero matching @file{.drv} files, for instance
3666 because these files have been garbage-collected. There can also be more
3667 than one matching @file{.drv} due to fixed-output derivations.
3670 Lastly, the following options allow you to check the integrity of the
3671 store and to control disk usage.
3675 @item --verify[=@var{options}]
3676 @cindex integrity, of the store
3677 @cindex integrity checking
3678 Verify the integrity of the store.
3680 By default, make sure that all the store items marked as valid in the
3681 database of the daemon actually exist in @file{/gnu/store}.
3683 When provided, @var{options} must be a comma-separated list containing one
3684 or more of @code{contents} and @code{repair}.
3686 When passing @option{--verify=contents}, the daemon computes the
3687 content hash of each store item and compares it against its hash in the
3688 database. Hash mismatches are reported as data corruptions. Because it
3689 traverses @emph{all the files in the store}, this command can take a
3690 long time, especially on systems with a slow disk drive.
3692 @cindex repairing the store
3693 @cindex corruption, recovering from
3694 Using @option{--verify=repair} or @option{--verify=contents,repair}
3695 causes the daemon to try to repair corrupt store items by fetching
3696 substitutes for them (@pxref{Substitutes}). Because repairing is not
3697 atomic, and thus potentially dangerous, it is available only to the
3698 system administrator. A lightweight alternative, when you know exactly
3699 which items in the store are corrupt, is @command{guix build --repair}
3700 (@pxref{Invoking guix build}).
3703 @cindex deduplication
3704 Optimize the store by hard-linking identical files---this is
3705 @dfn{deduplication}.
3707 The daemon performs deduplication after each successful build or archive
3708 import, unless it was started with @option{--disable-deduplication}
3709 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
3710 this option is primarily useful when the daemon was running with
3711 @option{--disable-deduplication}.
3715 @node Invoking guix pull
3716 @section Invoking @command{guix pull}
3718 @cindex upgrading Guix
3719 @cindex updating Guix
3720 @cindex @command{guix pull}
3722 Packages are installed or upgraded to the latest version available in
3723 the distribution currently available on your local machine. To update
3724 that distribution, along with the Guix tools, you must run @command{guix
3725 pull}: the command downloads the latest Guix source code and package
3726 descriptions, and deploys it. Source code is downloaded from a
3727 @uref{https://git-scm.com, Git} repository, by default the official
3728 GNU@tie{}Guix repository, though this can be customized.
3730 Specifically, @command{guix pull} downloads code from the @dfn{channels}
3731 (@pxref{Channels}) specified by one of the followings, in this order:
3735 the @option{--channels} option;
3737 the user's @file{~/.config/guix/channels.scm} file;
3739 the system-wide @file{/etc/guix/channels.scm} file;
3741 the built-in default channels specified in the @code{%default-channels}
3745 On completion, @command{guix package} will use packages and package
3746 versions from this just-retrieved copy of Guix. Not only that, but all
3747 the Guix commands and Scheme modules will also be taken from that latest
3748 version. New @command{guix} sub-commands added by the update also
3751 Any user can update their Guix copy using @command{guix pull}, and the
3752 effect is limited to the user who ran @command{guix pull}. For
3753 instance, when user @code{root} runs @command{guix pull}, this has no
3754 effect on the version of Guix that user @code{alice} sees, and vice
3757 The result of running @command{guix pull} is a @dfn{profile} available
3758 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3759 make sure to add it to the beginning of your search path so that you use
3760 the latest version, and similarly for the Info manual
3761 (@pxref{Documentation}):
3764 export PATH="$HOME/.config/guix/current/bin:$PATH"
3765 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3768 The @option{--list-generations} or @option{-l} option lists past generations
3769 produced by @command{guix pull}, along with details about their provenance:
3773 Generation 1 Jun 10 2018 00:18:18
3775 repository URL: https://git.savannah.gnu.org/git/guix.git
3776 branch: origin/master
3777 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3779 Generation 2 Jun 11 2018 11:02:49
3781 repository URL: https://git.savannah.gnu.org/git/guix.git
3782 branch: origin/master
3783 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3784 2 new packages: keepalived, libnfnetlink
3785 6 packages upgraded: emacs-nix-mode@@2.0.4,
3786 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3787 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3789 Generation 3 Jun 13 2018 23:31:07 (current)
3791 repository URL: https://git.savannah.gnu.org/git/guix.git
3792 branch: origin/master
3793 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3794 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3795 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3798 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3799 describe the current status of Guix.
3801 This @code{~/.config/guix/current} profile works exactly like the profiles
3802 created by @command{guix package} (@pxref{Invoking guix package}). That
3803 is, you can list generations, roll back to the previous
3804 generation---i.e., the previous Guix---and so on:
3807 $ guix pull --roll-back
3808 switched from generation 3 to 2
3809 $ guix pull --delete-generations=1
3810 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3813 You can also use @command{guix package} (@pxref{Invoking guix package})
3814 to manage the profile by naming it explicitly:
3816 $ guix package -p ~/.config/guix/current --roll-back
3817 switched from generation 3 to 2
3818 $ guix package -p ~/.config/guix/current --delete-generations=1
3819 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3822 The @command{guix pull} command is usually invoked with no arguments,
3823 but it supports the following options:
3826 @item --url=@var{url}
3827 @itemx --commit=@var{commit}
3828 @itemx --branch=@var{branch}
3829 Download code for the @code{guix} channel from the specified @var{url}, at the
3830 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3831 string), or @var{branch}.
3833 @cindex @file{channels.scm}, configuration file
3834 @cindex configuration file for channels
3835 These options are provided for convenience, but you can also specify your
3836 configuration in the @file{~/.config/guix/channels.scm} file or using the
3837 @option{--channels} option (see below).
3839 @item --channels=@var{file}
3840 @itemx -C @var{file}
3841 Read the list of channels from @var{file} instead of
3842 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
3843 @var{file} must contain Scheme code that
3844 evaluates to a list of channel objects. @xref{Channels}, for more
3847 @cindex channel news
3850 Display the list of packages added or upgraded since the previous
3851 generation, as well as, occasionally, news written by channel authors
3852 for their users (@pxref{Channels, Writing Channel News}).
3854 The package information is the same as displayed upon @command{guix
3855 pull} completion, but without ellipses; it is also similar to the output
3856 of @command{guix pull -l} for the last generation (see below).
3858 @item --list-generations[=@var{pattern}]
3859 @itemx -l [@var{pattern}]
3860 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3861 is provided, the subset of generations that match @var{pattern}.
3862 The syntax of @var{pattern} is the same as with @code{guix package
3863 --list-generations} (@pxref{Invoking guix package}).
3866 @cindex rolling back
3867 @cindex undoing transactions
3868 @cindex transactions, undoing
3869 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
3870 undo the last transaction.
3872 @item --switch-generation=@var{pattern}
3873 @itemx -S @var{pattern}
3875 Switch to a particular generation defined by @var{pattern}.
3877 @var{pattern} may be either a generation number or a number prefixed
3878 with ``+'' or ``-''. The latter means: move forward/backward by a
3879 specified number of generations. For example, if you want to return to
3880 the latest generation after @option{--roll-back}, use
3881 @option{--switch-generation=+1}.
3883 @item --delete-generations[=@var{pattern}]
3884 @itemx -d [@var{pattern}]
3885 When @var{pattern} is omitted, delete all generations except the current
3888 This command accepts the same patterns as @option{--list-generations}.
3889 When @var{pattern} is specified, delete the matching generations. When
3890 @var{pattern} specifies a duration, generations @emph{older} than the
3891 specified duration match. For instance, @option{--delete-generations=1m}
3892 deletes generations that are more than one month old.
3894 If the current generation matches, it is @emph{not} deleted.
3896 Note that deleting generations prevents rolling back to them.
3897 Consequently, this command must be used with care.
3899 @xref{Invoking guix describe}, for a way to display information about the
3900 current generation only.
3902 @item --profile=@var{profile}
3903 @itemx -p @var{profile}
3904 Use @var{profile} instead of @file{~/.config/guix/current}.
3908 Show which channel commit(s) would be used and what would be built or
3909 substituted but do not actually do it.
3911 @item --allow-downgrades
3912 Allow pulling older or unrelated revisions of channels than those
3915 @cindex downgrade attacks, protection against
3916 By default, @command{guix pull} protects against so-called ``downgrade
3917 attacks'' whereby the Git repository of a channel would be reset to an
3918 earlier or unrelated revision of itself, potentially leading you to
3919 install older, known-vulnerable versions of software packages.
3922 Make sure you understand its security implications before using
3923 @option{--allow-downgrades}.
3926 @item --system=@var{system}
3927 @itemx -s @var{system}
3928 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3929 the system type of the build host.
3932 Produce verbose output, writing build logs to the standard error output.
3935 Use the bootstrap Guile to build the latest Guix. This option is only
3936 useful to Guix developers.
3939 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3940 repository and branch to pull from, as well as @emph{additional} repositories
3941 containing package modules that should be deployed. @xref{Channels}, for more
3944 In addition, @command{guix pull} supports all the common build options
3945 (@pxref{Common Build Options}).
3951 @cindex @file{channels.scm}, configuration file
3952 @cindex configuration file for channels
3953 @cindex @command{guix pull}, configuration file
3954 @cindex configuration of @command{guix pull}
3955 Guix and its package collection are updated by running @command{guix pull}
3956 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3957 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3958 customized by defining @dfn{channels} in the
3959 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3960 of a Git repository to be deployed, and @command{guix pull} can be instructed
3961 to pull from one or more channels. In other words, channels can be used to
3962 @emph{customize} and to @emph{extend} Guix, as we will see below.
3964 @subsection Using a Custom Guix Channel
3966 The channel called @code{guix} specifies where Guix itself---its command-line
3967 tools as well as its package collection---should be downloaded. For instance,
3968 suppose you want to update from your own copy of the Guix repository at
3969 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3970 write in @code{~/.config/guix/channels.scm} this specification:
3973 ;; Tell 'guix pull' to use my own repo.
3976 (url "https://example.org/my-guix.git")
3977 (branch "super-hacks")))
3981 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3982 branch of the repository at @code{example.org}.
3984 @subsection Specifying Additional Channels
3986 @cindex extending the package collection (channels)
3987 @cindex personal packages (channels)
3988 @cindex channels, for personal packages
3989 You can also specify @emph{additional channels} to pull from. Let's say you
3990 have a bunch of custom package variants or personal packages that you think
3991 would make little sense to contribute to the Guix project, but would like to
3992 have these packages transparently available to you at the command line. You
3993 would first write modules containing those package definitions (@pxref{Package
3994 Modules}), maintain them in a Git repository, and then you and anyone else can
3995 use it as an additional channel to get packages from. Neat, no?
3997 @c What follows stems from discussions at
3998 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3999 @c earlier discussions on guix-devel@gnu.org.
4001 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
4002 publish your personal channel to the world, we would like to share a few words
4007 Before publishing a channel, please consider contributing your package
4008 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
4009 to free software of all sorts, and packages in Guix proper are readily
4010 available to all Guix users and benefit from the project's quality assurance
4014 When you maintain package definitions outside Guix, we, Guix developers,
4015 consider that @emph{the compatibility burden is on you}. Remember that
4016 package modules and package definitions are just Scheme code that uses various
4017 programming interfaces (APIs). We want to remain free to change these APIs to
4018 keep improving Guix, possibly in ways that break your channel. We never
4019 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
4023 Corollary: if you're using an external channel and that channel breaks, please
4024 @emph{report the issue to the channel authors}, not to the Guix project.
4027 You've been warned! Having said this, we believe external channels are a
4028 practical way to exert your freedom to augment Guix' package collection and to
4029 share your improvements, which are basic tenets of
4030 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
4031 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
4034 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
4035 @command{guix pull} to pull from it @emph{in addition} to the default Guix
4038 @vindex %default-channels
4040 ;; Add my personal packages to those Guix provides.
4042 (name 'my-personal-packages)
4043 (url "https://example.org/personal-packages.git"))
4048 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4049 add a channel the list of channels that the variable @code{%default-channels}
4050 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4051 Manual}). With this file in place, @command{guix pull} builds not only Guix
4052 but also the package modules from your own repository. The result in
4053 @file{~/.config/guix/current} is the union of Guix with your own package
4057 $ guix pull --list-generations
4059 Generation 19 Aug 27 2018 16:20:48
4061 repository URL: https://git.savannah.gnu.org/git/guix.git
4063 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4064 my-personal-packages dd3df5e
4065 repository URL: https://example.org/personal-packages.git
4067 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4068 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
4069 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4073 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4074 both Guix and packages from the @code{my-personal-packages} channel. Among
4075 the new and upgraded packages that are listed, some like @code{my-gimp} and
4076 @code{my-emacs-with-cool-features} might come from
4077 @code{my-personal-packages}, while others come from the Guix default channel.
4079 To create a channel, create a Git repository containing your own package
4080 modules and make it available. The repository can contain anything, but a
4081 useful channel will contain Guile modules that export packages. Once you
4082 start using a channel, Guix will behave as if the root directory of that
4083 channel's Git repository has been added to the Guile load path (@pxref{Load
4084 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
4085 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
4086 module, then the module will be available under the name @code{(my-packages
4087 my-tools)}, and you will be able to use it like any other module
4088 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
4090 @cindex dependencies, channels
4091 @cindex meta-data, channels
4092 @subsection Declaring Channel Dependencies
4094 Channel authors may decide to augment a package collection provided by other
4095 channels. They can declare their channel to be dependent on other channels in
4096 a meta-data file @file{.guix-channel}, which is to be placed in the root of
4097 the channel repository.
4099 The meta-data file should contain a simple S-expression like this:
4106 (name some-collection)
4107 (url "https://example.org/first-collection.git"))
4109 (name some-other-collection)
4110 (url "https://example.org/second-collection.git")
4111 (branch "testing"))))
4114 In the above example this channel is declared to depend on two other channels,
4115 which will both be fetched automatically. The modules provided by the channel
4116 will be compiled in an environment where the modules of all these declared
4117 channels are available.
4119 For the sake of reliability and maintainability, you should avoid dependencies
4120 on channels that you don't control, and you should aim to keep the number of
4121 dependencies to a minimum.
4123 @cindex subdirectory, channels
4124 @subsection Package Modules in a Sub-directory
4126 As a channel author, you may want to keep your channel modules in a
4127 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4128 add a meta-data file @file{.guix-channel} that contains:
4136 @cindex news, for channels
4137 @subsection Writing Channel News
4139 Channel authors may occasionally want to communicate to their users
4140 information about important changes in the channel. You'd send them all
4141 an email, but that's not convenient.
4143 Instead, channels can provide a @dfn{news file}; when the channel users
4144 run @command{guix pull}, that news file is automatically read and
4145 @command{guix pull --news} can display the announcements that correspond
4146 to the new commits that have been pulled, if any.
4148 To do that, channel authors must first declare the name of the news file
4149 in their @file{.guix-channel} file:
4154 (news-file "etc/news.txt"))
4157 The news file itself, @file{etc/news.txt} in this example, must look
4158 something like this:
4163 (entry (tag "the-bug-fix")
4164 (title (en "Fixed terrible bug")
4166 (body (en "@@emph@{Good news@}! It's fixed!")
4167 (eo "Certe ĝi pli bone funkcias nun!")))
4168 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4169 (title (en "Added a great package")
4170 (ca "Què vol dir guix?"))
4171 (body (en "Don't miss the @@code@{hello@} package!"))))
4174 The file consists of a list of @dfn{news entries}. Each entry is
4175 associated with a commit or tag: it describes changes made in this
4176 commit, possibly in preceding commits as well. Users see entries only
4177 the first time they obtain the commit the entry refers to.
4179 The @code{title} field should be a one-line summary while @code{body}
4180 can be arbitrarily long, and both can contain Texinfo markup
4181 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4182 a list of language tag/message tuples, which allows @command{guix pull}
4183 to display news in the language that corresponds to the user's locale.
4185 If you want to translate news using a gettext-based workflow, you can
4186 extract translatable strings with @command{xgettext} (@pxref{xgettext
4187 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4188 you write news entries in English first, the command below creates a PO
4189 file containing the strings to translate:
4192 xgettext -o news.po -l scheme -ken etc/news.scm
4195 To sum up, yes, you could use your channel as a blog. But beware, this
4196 is @emph{not quite} what your users might expect.
4198 @subsection Replicating Guix
4200 @cindex pinning, channels
4201 @cindex replicating Guix
4202 @cindex reproducibility, of Guix
4203 The @command{guix pull --list-generations} output above shows precisely which
4204 commits were used to build this instance of Guix. We can thus replicate it,
4205 say, on another machine, by providing a channel specification in
4206 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4209 ;; Deploy specific commits of my channels of interest.
4212 (url "https://git.savannah.gnu.org/git/guix.git")
4213 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
4215 (name 'my-personal-packages)
4216 (url "https://example.org/personal-packages.git")
4217 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4220 The @command{guix describe --format=channels} command can even generate this
4221 list of channels directly (@pxref{Invoking guix describe}). The resulting
4222 file can be used with the -C options of @command{guix pull}
4223 (@pxref{Invoking guix pull}) or @command{guix time-machine}
4224 (@pxref{Invoking guix time-machine}).
4226 At this point the two machines run the @emph{exact same Guix}, with access to
4227 the @emph{exact same packages}. The output of @command{guix build gimp} on
4228 one machine will be exactly the same, bit for bit, as the output of the same
4229 command on the other machine. It also means both machines have access to all
4230 the source code of Guix and, transitively, to all the source code of every
4233 This gives you super powers, allowing you to track the provenance of binary
4234 artifacts with very fine grain, and to reproduce software environments at
4235 will---some sort of ``meta reproducibility'' capabilities, if you will.
4236 @xref{Inferiors}, for another way to take advantage of these super powers.
4238 @node Invoking guix time-machine
4239 @section Invoking @command{guix time-machine}
4241 @cindex @command{guix time-machine}
4242 @cindex pinning, channels
4243 @cindex replicating Guix
4244 @cindex reproducibility, of Guix
4246 The @command{guix time-machine} command provides access to other
4247 revisions of Guix, for example to install older versions of packages,
4248 or to reproduce a computation in an identical environment. The revision
4249 of Guix to be used is defined by a commit or by a channel
4250 description file created by @command{guix describe}
4251 (@pxref{Invoking guix describe}).
4253 The general syntax is:
4256 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4259 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4260 @command{guix} command of the specified revision. The @var{options} that define
4261 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4264 @item --url=@var{url}
4265 @itemx --commit=@var{commit}
4266 @itemx --branch=@var{branch}
4267 Use the @code{guix} channel from the specified @var{url}, at the
4268 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4269 string), or @var{branch}.
4271 @item --channels=@var{file}
4272 @itemx -C @var{file}
4273 Read the list of channels from @var{file}. @var{file} must contain
4274 Scheme code that evaluates to a list of channel objects.
4275 @xref{Channels} for more information.
4278 As for @command{guix pull}, the absence of any options means that the
4279 the latest commit on the master branch will be used. The command
4282 guix time-machine -- build hello
4285 will thus build the package @code{hello} as defined in the master branch,
4286 which is in general a newer revision of Guix than you have installed.
4287 Time travel works in both directions!
4289 Note that @command{guix time-machine} can trigger builds of channels and
4290 their dependencies, and these are controlled by the standard build
4291 options (@pxref{Common Build Options}).
4296 @c TODO: Remove this once we're more confident about API stability.
4298 The functionality described here is a ``technology preview'' as of version
4299 @value{VERSION}. As such, the interface is subject to change.
4303 @cindex composition of Guix revisions
4304 Sometimes you might need to mix packages from the revision of Guix you're
4305 currently running with packages available in a different revision of Guix.
4306 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4307 revisions in arbitrary ways.
4309 @cindex inferior packages
4310 Technically, an ``inferior'' is essentially a separate Guix process connected
4311 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4312 @code{(guix inferior)} module allows you to create inferiors and to
4313 communicate with them. It also provides a high-level interface to browse and
4314 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4316 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4317 to interact with a separate revision of Guix. For example, let's assume you
4318 want to install in your profile the current @code{guile} package, along with
4319 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4320 because the newer @code{guile-json} has an incompatible API and you want to
4321 run your code against the old API@. To do that, you could write a manifest for
4322 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4323 manifest, you would create an inferior for that old Guix revision you care
4324 about, and you would look up the @code{guile-json} package in the inferior:
4327 (use-modules (guix inferior) (guix channels)
4328 (srfi srfi-1)) ;for 'first'
4331 ;; This is the old revision from which we want to
4332 ;; extract guile-json.
4335 (url "https://git.savannah.gnu.org/git/guix.git")
4337 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4340 ;; An inferior representing the above revision.
4341 (inferior-for-channels channels))
4343 ;; Now create a manifest with the current "guile" package
4344 ;; and the old "guile-json" package.
4346 (list (first (lookup-inferior-packages inferior "guile-json"))
4347 (specification->package "guile")))
4350 On its first run, @command{guix package --manifest} might have to build the
4351 channel you specified before it can create the inferior; subsequent runs will
4352 be much faster because the Guix revision will be cached.
4354 The @code{(guix inferior)} module provides the following procedures to open an
4357 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4358 [#:cache-directory] [#:ttl]
4359 Return an inferior for @var{channels}, a list of channels. Use the cache at
4360 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4361 This procedure opens a new connection to the build daemon.
4363 As a side effect, this procedure may build or substitute binaries for
4364 @var{channels}, which can take time.
4367 @deffn {Scheme Procedure} open-inferior @var{directory} @
4368 [#:command "bin/guix"]
4369 Open the inferior Guix in @var{directory}, running
4370 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4371 the inferior could not be launched.
4374 @cindex inferior packages
4375 The procedures listed below allow you to obtain and manipulate inferior
4378 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4379 Return the list of packages known to @var{inferior}.
4382 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4384 Return the sorted list of inferior packages matching @var{name} in
4385 @var{inferior}, with highest version numbers first. If @var{version} is true,
4386 return only packages with a version number prefixed by @var{version}.
4389 @deffn {Scheme Procedure} inferior-package? @var{obj}
4390 Return true if @var{obj} is an inferior package.
4393 @deffn {Scheme Procedure} inferior-package-name @var{package}
4394 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4395 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4396 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4397 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4398 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4399 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4400 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4401 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4402 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4403 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4404 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4405 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4406 These procedures are the counterpart of package record accessors
4407 (@pxref{package Reference}). Most of them work by querying the inferior
4408 @var{package} comes from, so the inferior must still be live when you call
4412 Inferior packages can be used transparently like any other package or
4413 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4414 transparently handled by the @code{packages->manifest} procedure, which is
4415 commonly use in manifests (@pxref{Invoking guix package, the
4416 @option{--manifest} option of @command{guix package}}). Thus you can insert
4417 an inferior package pretty much anywhere you would insert a regular package:
4418 in manifests, in the @code{packages} field of your @code{operating-system}
4419 declaration, and so on.
4421 @node Invoking guix describe
4422 @section Invoking @command{guix describe}
4424 @cindex reproducibility
4425 @cindex replicating Guix
4426 Often you may want to answer questions like: ``Which revision of Guix am I
4427 using?'' or ``Which channels am I using?'' This is useful information in many
4428 situations: if you want to @emph{replicate} an environment on a different
4429 machine or user account, if you want to report a bug or to determine what
4430 change in the channels you are using caused it, or if you want to record your
4431 system state for reproducibility purposes. The @command{guix describe}
4432 command answers these questions.
4434 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4435 displays the channel(s) that it was built from, including their repository URL
4436 and commit IDs (@pxref{Channels}):
4440 Generation 10 Sep 03 2018 17:32:44 (current)
4442 repository URL: https://git.savannah.gnu.org/git/guix.git
4444 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4447 If you're familiar with the Git version control system, this is similar in
4448 spirit to @command{git describe}; the output is also similar to that of
4449 @command{guix pull --list-generations}, but limited to the current generation
4450 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4451 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4452 information is all it takes to describe the revision of Guix you're using, and
4453 also to replicate it.
4455 To make it easier to replicate Guix, @command{guix describe} can also be asked
4456 to return a list of channels instead of the human-readable description above:
4459 $ guix describe -f channels
4462 (url "https://git.savannah.gnu.org/git/guix.git")
4464 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4468 You can save this to a file and feed it to @command{guix pull -C} on some
4469 other machine or at a later point in time, which will instantiate @emph{this
4470 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4471 From there on, since you're able to deploy the same revision of Guix, you can
4472 just as well @emph{replicate a complete software environment}. We humbly
4473 think that this is @emph{awesome}, and we hope you'll like it too!
4475 The details of the options supported by @command{guix describe} are as
4479 @item --format=@var{format}
4480 @itemx -f @var{format}
4481 Produce output in the specified @var{format}, one of:
4485 produce human-readable output;
4487 produce a list of channel specifications that can be passed to @command{guix
4488 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4492 produce a list of channel specifications in JSON format;
4494 produce a list of channel specifications in Recutils format.
4497 @item --list-formats
4498 Display available formats for @option{--format} option.
4500 @item --profile=@var{profile}
4501 @itemx -p @var{profile}
4502 Display information about @var{profile}.
4505 @node Invoking guix archive
4506 @section Invoking @command{guix archive}
4508 @cindex @command{guix archive}
4510 The @command{guix archive} command allows users to @dfn{export} files
4511 from the store into a single archive, and to later @dfn{import} them on
4512 a machine that runs Guix.
4513 In particular, it allows store files to be transferred from one machine
4514 to the store on another machine.
4517 If you're looking for a way to produce archives in a format suitable for
4518 tools other than Guix, @pxref{Invoking guix pack}.
4521 @cindex exporting store items
4522 To export store files as an archive to standard output, run:
4525 guix archive --export @var{options} @var{specifications}...
4528 @var{specifications} may be either store file names or package
4529 specifications, as for @command{guix package} (@pxref{Invoking guix
4530 package}). For instance, the following command creates an archive
4531 containing the @code{gui} output of the @code{git} package and the main
4532 output of @code{emacs}:
4535 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4538 If the specified packages are not built yet, @command{guix archive}
4539 automatically builds them. The build process may be controlled with the
4540 common build options (@pxref{Common Build Options}).
4542 To transfer the @code{emacs} package to a machine connected over SSH,
4546 guix archive --export -r emacs | ssh the-machine guix archive --import
4550 Similarly, a complete user profile may be transferred from one machine
4551 to another like this:
4554 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4555 ssh the-machine guix archive --import
4559 However, note that, in both examples, all of @code{emacs} and the
4560 profile as well as all of their dependencies are transferred (due to
4561 @option{-r}), regardless of what is already available in the store on
4562 the target machine. The @option{--missing} option can help figure out
4563 which items are missing from the target store. The @command{guix copy}
4564 command simplifies and optimizes this whole process, so this is probably
4565 what you should use in this case (@pxref{Invoking guix copy}).
4567 @cindex nar, archive format
4568 @cindex normalized archive (nar)
4569 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4570 comparable in spirit to `tar', but with differences
4571 that make it more appropriate for our purposes. First, rather than
4572 recording all Unix metadata for each file, the nar format only mentions
4573 the file type (regular, directory, or symbolic link); Unix permissions
4574 and owner/group are dismissed. Second, the order in which directory
4575 entries are stored always follows the order of file names according to
4576 the C locale collation order. This makes archive production fully
4579 When exporting, the daemon digitally signs the contents of the archive,
4580 and that digital signature is appended. When importing, the daemon
4581 verifies the signature and rejects the import in case of an invalid
4582 signature or if the signing key is not authorized.
4583 @c FIXME: Add xref to daemon doc about signatures.
4585 The main options are:
4589 Export the specified store files or packages (see below). Write the
4590 resulting archive to the standard output.
4592 Dependencies are @emph{not} included in the output, unless
4593 @option{--recursive} is passed.
4597 When combined with @option{--export}, this instructs @command{guix archive}
4598 to include dependencies of the given items in the archive. Thus, the
4599 resulting archive is self-contained: it contains the closure of the
4600 exported store items.
4603 Read an archive from the standard input, and import the files listed
4604 therein into the store. Abort if the archive has an invalid digital
4605 signature, or if it is signed by a public key not among the authorized
4606 keys (see @option{--authorize} below).
4609 Read a list of store file names from the standard input, one per line,
4610 and write on the standard output the subset of these files missing from
4613 @item --generate-key[=@var{parameters}]
4614 @cindex signing, archives
4615 Generate a new key pair for the daemon. This is a prerequisite before
4616 archives can be exported with @option{--export}. Note that this
4617 operation usually takes time, because it needs to gather enough entropy
4618 to generate the key pair.
4620 The generated key pair is typically stored under @file{/etc/guix}, in
4621 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4622 key, which must be kept secret). When @var{parameters} is omitted,
4623 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4624 versions before 1.6.0, it is a 4096-bit RSA key.
4625 Alternatively, @var{parameters} can specify
4626 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4627 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4628 Libgcrypt Reference Manual}).
4631 @cindex authorizing, archives
4632 Authorize imports signed by the public key passed on standard input.
4633 The public key must be in ``s-expression advanced format''---i.e., the
4634 same format as the @file{signing-key.pub} file.
4636 The list of authorized keys is kept in the human-editable file
4637 @file{/etc/guix/acl}. The file contains
4638 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4639 s-expressions''} and is structured as an access-control list in the
4640 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4643 @item --extract=@var{directory}
4644 @itemx -x @var{directory}
4645 Read a single-item archive as served by substitute servers
4646 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4647 low-level operation needed in only very narrow use cases; see below.
4649 For example, the following command extracts the substitute for Emacs
4650 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4654 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4655 | gunzip | guix archive -x /tmp/emacs
4658 Single-item archives are different from multiple-item archives produced
4659 by @command{guix archive --export}; they contain a single store item,
4660 and they do @emph{not} embed a signature. Thus this operation does
4661 @emph{no} signature verification and its output should be considered
4664 The primary purpose of this operation is to facilitate inspection of
4665 archive contents coming from possibly untrusted substitute servers
4666 (@pxref{Invoking guix challenge}).
4670 Read a single-item archive as served by substitute servers
4671 (@pxref{Substitutes}) and print the list of files it contains, as in
4676 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4677 | lzip -d | guix archive -t
4683 @c *********************************************************************
4685 @chapter Development
4687 @cindex software development
4688 If you are a software developer, Guix provides tools that you should find
4689 helpful---independently of the language you're developing in. This is what
4690 this chapter is about.
4692 The @command{guix environment} command provides a convenient way to set up
4693 @dfn{development environments} containing all the dependencies and tools
4694 necessary to work on the software package of your choice. The @command{guix
4695 pack} command allows you to create @dfn{application bundles} that can be
4696 easily distributed to users who do not run Guix.
4699 * Invoking guix environment:: Setting up development environments.
4700 * Invoking guix pack:: Creating software bundles.
4701 * The GCC toolchain:: Working with languages supported by GCC.
4704 @node Invoking guix environment
4705 @section Invoking @command{guix environment}
4707 @cindex reproducible build environments
4708 @cindex development environments
4709 @cindex @command{guix environment}
4710 @cindex environment, package build environment
4711 The purpose of @command{guix environment} is to assist hackers in
4712 creating reproducible development environments without polluting their
4713 package profile. The @command{guix environment} tool takes one or more
4714 packages, builds all of their inputs, and creates a shell
4715 environment to use them.
4717 The general syntax is:
4720 guix environment @var{options} @var{package}@dots{}
4723 The following example spawns a new shell set up for the development of
4727 guix environment guile
4730 If the needed dependencies are not built yet, @command{guix environment}
4731 automatically builds them. The environment of the new shell is an
4732 augmented version of the environment that @command{guix environment} was
4733 run in. It contains the necessary search paths for building the given
4734 package added to the existing environment variables. To create
4735 a ``pure'' environment, in which the original environment variables have
4736 been unset, use the @option{--pure} option@footnote{Users sometimes
4737 wrongfully augment environment variables such as @env{PATH} in their
4738 @file{~/.bashrc} file. As a consequence, when @command{guix
4739 environment} launches it, Bash may read @file{~/.bashrc}, thereby
4740 introducing ``impurities'' in these environment variables. It is an
4741 error to define such environment variables in @file{.bashrc}; instead,
4742 they should be defined in @file{.bash_profile}, which is sourced only by
4743 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
4744 Manual}, for details on Bash start-up files.}.
4746 @vindex GUIX_ENVIRONMENT
4747 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
4748 variable in the shell it spawns; its value is the file name of the
4749 profile of this environment. This allows users to, say, define a
4750 specific prompt for development environments in their @file{.bashrc}
4751 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4754 if [ -n "$GUIX_ENVIRONMENT" ]
4756 export PS1="\u@@\h \w [dev]\$ "
4761 ...@: or to browse the profile:
4764 $ ls "$GUIX_ENVIRONMENT/bin"
4767 Additionally, more than one package may be specified, in which case the
4768 union of the inputs for the given packages are used. For example, the
4769 command below spawns a shell where all of the dependencies of both Guile
4770 and Emacs are available:
4773 guix environment guile emacs
4776 Sometimes an interactive shell session is not desired. An arbitrary
4777 command may be invoked by placing the @code{--} token to separate the
4778 command from the rest of the arguments:
4781 guix environment guile -- make -j4
4784 In other situations, it is more convenient to specify the list of
4785 packages needed in the environment. For example, the following command
4786 runs @command{python} from an environment containing Python@tie{}2.7 and
4790 guix environment --ad-hoc python2-numpy python-2.7 -- python
4793 Furthermore, one might want the dependencies of a package and also some
4794 additional packages that are not build-time or runtime dependencies, but
4795 are useful when developing nonetheless. Because of this, the
4796 @option{--ad-hoc} flag is positional. Packages appearing before
4797 @option{--ad-hoc} are interpreted as packages whose dependencies will be
4798 added to the environment. Packages appearing after are interpreted as
4799 packages that will be added to the environment directly. For example,
4800 the following command creates a Guix development environment that
4801 additionally includes Git and strace:
4804 guix environment --pure guix --ad-hoc git strace
4808 Sometimes it is desirable to isolate the environment as much as
4809 possible, for maximal purity and reproducibility. In particular, when
4810 using Guix on a host distro that is not Guix System, it is desirable to
4811 prevent access to @file{/usr/bin} and other system-wide resources from
4812 the development environment. For example, the following command spawns
4813 a Guile REPL in a ``container'' where only the store and the current
4814 working directory are mounted:
4817 guix environment --ad-hoc --container guile -- guile
4821 The @option{--container} option requires Linux-libre 3.19 or newer.
4824 @cindex certificates
4825 Another typical use case for containers is to run security-sensitive
4826 applications such as a web browser. To run Eolie, we must expose and
4827 share some files and directories; we include @code{nss-certs} and expose
4828 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
4829 the @env{DISPLAY} environment variable since containerized graphical
4830 applications won't display without it.
4833 guix environment --preserve='^DISPLAY$' --container --network \
4834 --expose=/etc/machine-id \
4835 --expose=/etc/ssl/certs/ \
4836 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
4837 --ad-hoc eolie nss-certs dbus -- eolie
4840 The available options are summarized below.
4843 @item --root=@var{file}
4844 @itemx -r @var{file}
4845 @cindex persistent environment
4846 @cindex garbage collector root, for environments
4847 Make @var{file} a symlink to the profile for this environment, and
4848 register it as a garbage collector root.
4850 This is useful if you want to protect your environment from garbage
4851 collection, to make it ``persistent''.
4853 When this option is omitted, the environment is protected from garbage
4854 collection only for the duration of the @command{guix environment}
4855 session. This means that next time you recreate the same environment,
4856 you could have to rebuild or re-download packages. @xref{Invoking guix
4857 gc}, for more on GC roots.
4859 @item --expression=@var{expr}
4860 @itemx -e @var{expr}
4861 Create an environment for the package or list of packages that
4862 @var{expr} evaluates to.
4864 For example, running:
4867 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4870 starts a shell with the environment for this specific variant of the
4876 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4879 starts a shell with all the base system packages available.
4881 The above commands only use the default output of the given packages.
4882 To select other outputs, two element tuples can be specified:
4885 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4888 @item --load=@var{file}
4889 @itemx -l @var{file}
4890 Create an environment for the package or list of packages that the code
4891 within @var{file} evaluates to.
4893 As an example, @var{file} might contain a definition like this
4894 (@pxref{Defining Packages}):
4897 @verbatiminclude environment-gdb.scm
4900 @item --manifest=@var{file}
4901 @itemx -m @var{file}
4902 Create an environment for the packages contained in the manifest object
4903 returned by the Scheme code in @var{file}. This option can be repeated
4904 several times, in which case the manifests are concatenated.
4906 This is similar to the same-named option in @command{guix package}
4907 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4911 Include all specified packages in the resulting environment, as if an
4912 @i{ad hoc} package were defined with them as inputs. This option is
4913 useful for quickly creating an environment without having to write a
4914 package expression to contain the desired inputs.
4916 For instance, the command:
4919 guix environment --ad-hoc guile guile-sdl -- guile
4922 runs @command{guile} in an environment where Guile and Guile-SDL are
4925 Note that this example implicitly asks for the default output of
4926 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4927 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4928 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4930 This option may be composed with the default behavior of @command{guix
4931 environment}. Packages appearing before @option{--ad-hoc} are
4932 interpreted as packages whose dependencies will be added to the
4933 environment, the default behavior. Packages appearing after are
4934 interpreted as packages that will be added to the environment directly.
4937 Unset existing environment variables when building the new environment, except
4938 those specified with @option{--preserve} (see below). This has the effect of
4939 creating an environment in which search paths only contain package inputs.
4941 @item --preserve=@var{regexp}
4942 @itemx -E @var{regexp}
4943 When used alongside @option{--pure}, preserve the environment variables
4944 matching @var{regexp}---in other words, put them on a ``white list'' of
4945 environment variables that must be preserved. This option can be repeated
4949 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4953 This example runs @command{mpirun} in a context where the only environment
4954 variables defined are @env{PATH}, environment variables whose name starts
4955 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
4958 @item --search-paths
4959 Display the environment variable definitions that make up the
4962 @item --system=@var{system}
4963 @itemx -s @var{system}
4964 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4969 Run @var{command} within an isolated container. The current working
4970 directory outside the container is mapped inside the container.
4971 Additionally, unless overridden with @option{--user}, a dummy home
4972 directory is created that matches the current user's home directory, and
4973 @file{/etc/passwd} is configured accordingly.
4975 The spawned process runs as the current user outside the container. Inside
4976 the container, it has the same UID and GID as the current user, unless
4977 @option{--user} is passed (see below).
4981 For containers, share the network namespace with the host system.
4982 Containers created without this flag only have access to the loopback
4985 @item --link-profile
4987 For containers, link the environment profile to @file{~/.guix-profile}
4988 within the container. This is equivalent to running the command
4989 @samp{ln -s $GUIX_ENVIRONMENT ~/.guix-profile} within the container.
4990 Linking will fail and abort the environment if the directory already
4991 exists, which will certainly be the case if @command{guix environment}
4992 was invoked in the user's home directory.
4994 Certain packages are configured to look in @file{~/.guix-profile} for
4995 configuration files and data;@footnote{For example, the
4996 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
4997 for additional fonts.} @option{--link-profile} allows these programs to
4998 behave as expected within the environment.
5000 @item --user=@var{user}
5001 @itemx -u @var{user}
5002 For containers, use the username @var{user} in place of the current
5003 user. The generated @file{/etc/passwd} entry within the container will
5004 contain the name @var{user}, the home directory will be
5005 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5006 the UID and GID inside the container are 1000. @var{user}
5007 need not exist on the system.
5009 Additionally, any shared or exposed path (see @option{--share} and
5010 @option{--expose} respectively) whose target is within the current user's
5011 home directory will be remapped relative to @file{/home/USER}; this
5012 includes the automatic mapping of the current working directory.
5015 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5017 guix environment --container --user=foo \
5018 --expose=$HOME/test \
5019 --expose=/tmp/target=$HOME/target
5022 While this will limit the leaking of user identity through home paths
5023 and each of the user fields, this is only one useful component of a
5024 broader privacy/anonymity solution---not one in and of itself.
5027 For containers, the default behavior is to share the current working
5028 directory with the isolated container and immediately change to that
5029 directory within the container. If this is undesirable,
5030 @option{--no-cwd} will cause the current working directory to @emph{not}
5031 be automatically shared and will change to the user's home directory
5032 within the container instead. See also @option{--user}.
5034 @item --expose=@var{source}[=@var{target}]
5035 @itemx --share=@var{source}[=@var{target}]
5036 For containers, @option{--expose} (resp. @option{--share}) exposes the
5037 file system @var{source} from the host system as the read-only
5038 (resp. writable) file system @var{target} within the container. If
5039 @var{target} is not specified, @var{source} is used as the target mount
5040 point in the container.
5042 The example below spawns a Guile REPL in a container in which the user's
5043 home directory is accessible read-only via the @file{/exchange}
5047 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5052 @command{guix environment}
5053 also supports all of the common build options that @command{guix
5054 build} supports (@pxref{Common Build Options}) as well as package
5055 transformation options (@pxref{Package Transformation Options}).
5057 @node Invoking guix pack
5058 @section Invoking @command{guix pack}
5060 Occasionally you want to pass software to people who are not (yet!)
5061 lucky enough to be using Guix. You'd tell them to run @command{guix
5062 package -i @var{something}}, but that's not possible in this case. This
5063 is where @command{guix pack} comes in.
5066 If you are looking for ways to exchange binaries among machines that
5067 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5068 publish}, and @ref{Invoking guix archive}.
5073 @cindex application bundle
5074 @cindex software bundle
5075 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5076 @dfn{software bundle}: it creates a tarball or some other archive
5077 containing the binaries of the software you're interested in, and all
5078 its dependencies. The resulting archive can be used on any machine that
5079 does not have Guix, and people can run the exact same binaries as those
5080 you have with Guix. The pack itself is created in a bit-reproducible
5081 fashion, so anyone can verify that it really contains the build results
5082 that you pretend to be shipping.
5084 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5085 their dependencies, you can run:
5088 $ guix pack guile emacs geiser
5090 /gnu/store/@dots{}-pack.tar.gz
5093 The result here is a tarball containing a @file{/gnu/store} directory
5094 with all the relevant packages. The resulting tarball contains a
5095 @dfn{profile} with the three packages of interest; the profile is the
5096 same as would be created by @command{guix package -i}. It is this
5097 mechanism that is used to create Guix's own standalone binary tarball
5098 (@pxref{Binary Installation}).
5100 Users of this pack would have to run
5101 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5102 find inconvenient. To work around it, you can create, say, a
5103 @file{/opt/gnu/bin} symlink to the profile:
5106 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5110 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5112 @cindex relocatable binaries, with @command{guix pack}
5113 What if the recipient of your pack does not have root privileges on
5114 their machine, and thus cannot unpack it in the root file system? In
5115 that case, you will want to use the @option{--relocatable} option (see
5116 below). This option produces @dfn{relocatable binaries}, meaning they
5117 they can be placed anywhere in the file system hierarchy: in the example
5118 above, users can unpack your tarball in their home directory and
5119 directly run @file{./opt/gnu/bin/guile}.
5121 @cindex Docker, build an image with guix pack
5122 Alternatively, you can produce a pack in the Docker image format using
5123 the following command:
5126 guix pack -f docker -S /bin=bin guile guile-readline
5130 The result is a tarball that can be passed to the @command{docker load}
5131 command, followed by @code{docker run}:
5134 docker load < @var{file}
5135 docker run -ti guile-guile-readline /bin/guile
5139 where @var{file} is the image returned by @var{guix pack}, and
5140 @code{guile-guile-readline} is its ``image tag''. See the
5141 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5142 documentation} for more information.
5144 @cindex Singularity, build an image with guix pack
5145 @cindex SquashFS, build an image with guix pack
5146 Yet another option is to produce a SquashFS image with the following
5150 guix pack -f squashfs bash guile emacs geiser
5154 The result is a SquashFS file system image that can either be mounted or
5155 directly be used as a file system container image with the
5156 @uref{https://www.sylabs.io/docs/, Singularity container execution
5157 environment}, using commands like @command{singularity shell} or
5158 @command{singularity exec}.
5160 Several command-line options allow you to customize your pack:
5163 @item --format=@var{format}
5164 @itemx -f @var{format}
5165 Produce a pack in the given @var{format}.
5167 The available formats are:
5171 This is the default format. It produces a tarball containing all the
5172 specified binaries and symlinks.
5175 This produces a tarball that follows the
5176 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5177 Docker Image Specification}. The ``repository name'' as it appears in
5178 the output of the @command{docker images} command is computed from
5179 package names passed on the command line or in the manifest file.
5182 This produces a SquashFS image containing all the specified binaries and
5183 symlinks, as well as empty mount points for virtual file systems like
5187 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5188 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5189 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5190 with something like:
5193 guix pack -f squashfs bash @dots{}
5196 If you forget the @code{bash} (or similar) package, @command{singularity
5197 run} and @command{singularity exec} will fail with an unhelpful ``no
5198 such file or directory'' message.
5202 @cindex relocatable binaries
5205 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5206 anywhere in the file system hierarchy and run from there.
5208 When this option is passed once, the resulting binaries require support for
5209 @dfn{user namespaces} in the kernel Linux; when passed
5210 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5211 PRoot support, can be thought of as the abbreviation of ``Really
5212 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
5213 other techniques if user namespaces are unavailable, and essentially
5214 work anywhere---see below for the implications.
5216 For example, if you create a pack containing Bash with:
5219 guix pack -RR -S /mybin=bin bash
5223 ...@: you can copy that pack to a machine that lacks Guix, and from your
5224 home directory as a normal user, run:
5232 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5233 @file{/gnu/store} shows up and contains all the dependencies of
5234 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5235 altogether! That is probably the simplest way to deploy Guix-built
5236 software on a non-Guix machine.
5239 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5240 the kernel Linux, which allows unprivileged users to mount or change root.
5241 Old versions of Linux did not support it, and some GNU/Linux distributions
5244 To produce relocatable binaries that work even in the absence of user
5245 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5246 case, binaries will try user namespace support and fall back to another
5247 @dfn{execution engine} if user namespaces are not supported. The
5248 following execution engines are supported:
5252 Try user namespaces and fall back to PRoot if user namespaces are not
5253 supported (see below).
5256 Try user namespaces and fall back to Fakechroot if user namespaces are
5257 not supported (see below).
5260 Run the program through user namespaces and abort if they are not
5264 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
5265 provides the necessary
5266 support for file system virtualization. It achieves that by using the
5267 @code{ptrace} system call on the running program. This approach has the
5268 advantage to work without requiring special kernel support, but it incurs
5269 run-time overhead every time a system call is made.
5272 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
5273 Fakechroot} virtualizes file system accesses by intercepting calls to C
5274 library functions such as @code{open}, @code{stat}, @code{exec}, and so
5275 on. Unlike PRoot, it incurs very little overhead. However, it does not
5276 always work: for example, some file system accesses made from within the
5277 C library are not intercepted, and file system accesses made @i{via}
5278 direct syscalls are not intercepted either, leading to erratic behavior.
5281 @vindex GUIX_EXECUTION_ENGINE
5282 When running a wrapped program, you can explicitly request one of the
5283 execution engines listed above by setting the
5284 @code{GUIX_EXECUTION_ENGINE} environment variable accordingly.
5287 @cindex entry point, for Docker images
5288 @item --entry-point=@var{command}
5289 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5290 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5291 support it. @var{command} must be relative to the profile contained in the
5294 The entry point specifies the command that tools like @code{docker run} or
5295 @code{singularity run} automatically start by default. For example, you can
5299 guix pack -f docker --entry-point=bin/guile guile
5302 The resulting pack can easily be loaded and @code{docker run} with no extra
5303 arguments will spawn @code{bin/guile}:
5306 docker load -i pack.tar.gz
5307 docker run @var{image-id}
5310 @item --expression=@var{expr}
5311 @itemx -e @var{expr}
5312 Consider the package @var{expr} evaluates to.
5314 This has the same purpose as the same-named option in @command{guix
5315 build} (@pxref{Additional Build Options, @option{--expression} in
5316 @command{guix build}}).
5318 @item --manifest=@var{file}
5319 @itemx -m @var{file}
5320 Use the packages contained in the manifest object returned by the Scheme
5321 code in @var{file}. This option can be repeated several times, in which
5322 case the manifests are concatenated.
5324 This has a similar purpose as the same-named option in @command{guix
5325 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5326 same manifest files. It allows you to define a collection of packages
5327 once and use it both for creating profiles and for creating archives
5328 for use on machines that do not have Guix installed. Note that you can
5329 specify @emph{either} a manifest file @emph{or} a list of packages,
5332 @item --system=@var{system}
5333 @itemx -s @var{system}
5334 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5335 the system type of the build host.
5337 @item --target=@var{triplet}
5338 @cindex cross-compilation
5339 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5340 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
5341 configuration triplets,, autoconf, Autoconf}).
5343 @item --compression=@var{tool}
5344 @itemx -C @var{tool}
5345 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5346 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
5348 @item --symlink=@var{spec}
5349 @itemx -S @var{spec}
5350 Add the symlinks specified by @var{spec} to the pack. This option can
5351 appear several times.
5353 @var{spec} has the form @code{@var{source}=@var{target}}, where
5354 @var{source} is the symlink that will be created and @var{target} is the
5357 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5358 symlink pointing to the @file{bin} sub-directory of the profile.
5360 @item --save-provenance
5361 Save provenance information for the packages passed on the command line.
5362 Provenance information includes the URL and commit of the channels in use
5365 Provenance information is saved in the
5366 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5367 usual package metadata---the name and version of each package, their
5368 propagated inputs, and so on. It is useful information to the recipient of
5369 the pack, who then knows how the pack was (supposedly) obtained.
5371 This option is not enabled by default because, like timestamps, provenance
5372 information contributes nothing to the build process. In other words, there
5373 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5374 Recording such ``silent'' metadata in the output thus potentially breaks the
5375 source-to-binary bitwise reproducibility property.
5377 @item --root=@var{file}
5378 @itemx -r @var{file}
5379 @cindex garbage collector root, for packs
5380 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5383 @item --localstatedir
5384 @itemx --profile-name=@var{name}
5385 Include the ``local state directory'', @file{/var/guix}, in the resulting
5386 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5387 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5388 @file{~root/.guix-profile}.
5390 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5391 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5392 the pack means that the store is ``complete'' and manageable by Guix;
5393 not providing it pack means that the store is ``dead'': items cannot be
5394 added to it or removed from it after extraction of the pack.
5396 One use case for this is the Guix self-contained binary tarball
5397 (@pxref{Binary Installation}).
5401 Print the name of the derivation that builds the pack.
5404 Use the bootstrap binaries to build the pack. This option is only
5405 useful to Guix developers.
5408 In addition, @command{guix pack} supports all the common build options
5409 (@pxref{Common Build Options}) and all the package transformation
5410 options (@pxref{Package Transformation Options}).
5413 @node The GCC toolchain
5414 @section The GCC toolchain
5418 @cindex linker wrapper
5419 @cindex toolchain, for C development
5420 @cindex toolchain, for Fortran development
5422 If you need a complete toolchain for compiling and linking C or C++
5423 source code, use the @code{gcc-toolchain} package. This package
5424 provides a complete GCC toolchain for C/C++ development, including GCC
5425 itself, the GNU C Library (headers and binaries, plus debugging symbols
5426 in the @code{debug} output), Binutils, and a linker wrapper.
5428 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
5429 passed to the linker, add corresponding @code{-rpath} arguments, and
5430 invoke the actual linker with this new set of arguments. You can instruct the
5431 wrapper to refuse to link against libraries not in the store by setting the
5432 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
5434 The package @code{gfortran-toolchain} provides a complete GCC toolchain
5435 for Fortran development. For other languages, please use
5436 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
5438 @c *********************************************************************
5439 @node Programming Interface
5440 @chapter Programming Interface
5442 GNU Guix provides several Scheme programming interfaces (APIs) to
5443 define, build, and query packages. The first interface allows users to
5444 write high-level package definitions. These definitions refer to
5445 familiar packaging concepts, such as the name and version of a package,
5446 its build system, and its dependencies. These definitions can then be
5447 turned into concrete build actions.
5449 Build actions are performed by the Guix daemon, on behalf of users. In a
5450 standard setup, the daemon has write access to the store---the
5451 @file{/gnu/store} directory---whereas users do not. The recommended
5452 setup also has the daemon perform builds in chroots, under a specific
5453 build users, to minimize interference with the rest of the system.
5456 Lower-level APIs are available to interact with the daemon and the
5457 store. To instruct the daemon to perform a build action, users actually
5458 provide it with a @dfn{derivation}. A derivation is a low-level
5459 representation of the build actions to be taken, and the environment in
5460 which they should occur---derivations are to package definitions what
5461 assembly is to C programs. The term ``derivation'' comes from the fact
5462 that build results @emph{derive} from them.
5464 This chapter describes all these APIs in turn, starting from high-level
5465 package definitions.
5468 * Package Modules:: Packages from the programmer's viewpoint.
5469 * Defining Packages:: Defining new packages.
5470 * Build Systems:: Specifying how packages are built.
5471 * The Store:: Manipulating the package store.
5472 * Derivations:: Low-level interface to package derivations.
5473 * The Store Monad:: Purely functional interface to the store.
5474 * G-Expressions:: Manipulating build expressions.
5475 * Invoking guix repl:: Fiddling with Guix interactively.
5478 @node Package Modules
5479 @section Package Modules
5481 From a programming viewpoint, the package definitions of the
5482 GNU distribution are provided by Guile modules in the @code{(gnu packages
5483 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5484 packages @dots{})} module name space are not necessarily ``GNU
5485 packages''. This module naming scheme follows the usual Guile module
5486 naming convention: @code{gnu} means that these modules are distributed
5487 as part of the GNU system, and @code{packages} identifies modules that
5488 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5489 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5490 module exports a variable named @code{emacs}, which is bound to a
5491 @code{<package>} object (@pxref{Defining Packages}).
5493 The @code{(gnu packages @dots{})} module name space is
5494 automatically scanned for packages by the command-line tools. For
5495 instance, when running @code{guix install emacs}, all the @code{(gnu
5496 packages @dots{})} modules are scanned until one that exports a package
5497 object whose name is @code{emacs} is found. This package search
5498 facility is implemented in the @code{(gnu packages)} module.
5500 @cindex customization, of packages
5501 @cindex package module search path
5502 Users can store package definitions in modules with different
5503 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5504 name and module name must match. For instance, the @code{(my-packages
5505 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5506 relative to the load path specified with @option{--load-path} or
5507 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5508 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5509 these package definitions visible to the user interfaces:
5513 By adding the directory containing your package modules to the search path
5514 with the @code{-L} flag of @command{guix package} and other commands
5515 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
5516 environment variable described below.
5519 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5520 pulls from it. A channel is essentially a Git repository containing package
5521 modules. @xref{Channels}, for more information on how to define and use
5525 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5527 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5528 This is a colon-separated list of directories to search for additional
5529 package modules. Directories listed in this variable take precedence
5530 over the own modules of the distribution.
5533 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5534 each package is built based solely on other packages in the
5535 distribution. The root of this dependency graph is a small set of
5536 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5537 bootstrap)} module. For more information on bootstrapping,
5538 @pxref{Bootstrapping}.
5540 @node Defining Packages
5541 @section Defining Packages
5543 The high-level interface to package definitions is implemented in the
5544 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5545 example, the package definition, or @dfn{recipe}, for the GNU Hello
5546 package looks like this:
5549 (define-module (gnu packages hello)
5550 #:use-module (guix packages)
5551 #:use-module (guix download)
5552 #:use-module (guix build-system gnu)
5553 #:use-module (guix licenses)
5554 #:use-module (gnu packages gawk))
5556 (define-public hello
5562 (uri (string-append "mirror://gnu/hello/hello-" version
5566 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5567 (build-system gnu-build-system)
5568 (arguments '(#:configure-flags '("--enable-silent-rules")))
5569 (inputs `(("gawk" ,gawk)))
5570 (synopsis "Hello, GNU world: An example GNU package")
5571 (description "Guess what GNU Hello prints!")
5572 (home-page "https://www.gnu.org/software/hello/")
5577 Without being a Scheme expert, the reader may have guessed the meaning
5578 of the various fields here. This expression binds the variable
5579 @code{hello} to a @code{<package>} object, which is essentially a record
5580 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5581 This package object can be inspected using procedures found in the
5582 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5583 returns---surprise!---@code{"hello"}.
5585 With luck, you may be able to import part or all of the definition of
5586 the package you are interested in from another repository, using the
5587 @code{guix import} command (@pxref{Invoking guix import}).
5589 In the example above, @var{hello} is defined in a module of its own,
5590 @code{(gnu packages hello)}. Technically, this is not strictly
5591 necessary, but it is convenient to do so: all the packages defined in
5592 modules under @code{(gnu packages @dots{})} are automatically known to
5593 the command-line tools (@pxref{Package Modules}).
5595 There are a few points worth noting in the above package definition:
5599 The @code{source} field of the package is an @code{<origin>} object
5600 (@pxref{origin Reference}, for the complete reference).
5601 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5602 meaning that the source is a file to be downloaded over FTP or HTTP.
5604 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5605 the GNU mirrors defined in @code{(guix download)}.
5607 The @code{sha256} field specifies the expected SHA256 hash of the file
5608 being downloaded. It is mandatory, and allows Guix to check the
5609 integrity of the file. The @code{(base32 @dots{})} form introduces the
5610 base32 representation of the hash. You can obtain this information with
5611 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5612 hash} (@pxref{Invoking guix hash}).
5615 When needed, the @code{origin} form can also have a @code{patches} field
5616 listing patches to be applied, and a @code{snippet} field giving a
5617 Scheme expression to modify the source code.
5620 @cindex GNU Build System
5621 The @code{build-system} field specifies the procedure to build the
5622 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5623 represents the familiar GNU Build System, where packages may be
5624 configured, built, and installed with the usual @code{./configure &&
5625 make && make check && make install} command sequence.
5628 The @code{arguments} field specifies options for the build system
5629 (@pxref{Build Systems}). Here it is interpreted by
5630 @var{gnu-build-system} as a request run @file{configure} with the
5631 @option{--enable-silent-rules} flag.
5637 What about these quote (@code{'}) characters? They are Scheme syntax to
5638 introduce a literal list; @code{'} is synonymous with @code{quote}.
5639 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5640 for details. Here the value of the @code{arguments} field is a list of
5641 arguments passed to the build system down the road, as with @code{apply}
5642 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5645 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5646 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5647 @code{#:configure-flags} is a keyword used to pass a keyword argument
5648 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5652 The @code{inputs} field specifies inputs to the build process---i.e.,
5653 build-time or run-time dependencies of the package. Here, we define an
5654 input called @code{"gawk"} whose value is that of the @var{gawk}
5655 variable; @var{gawk} is itself bound to a @code{<package>} object.
5657 @cindex backquote (quasiquote)
5660 @cindex comma (unquote)
5664 @findex unquote-splicing
5665 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5666 us to introduce a literal list in the @code{inputs} field, while
5667 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5668 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5671 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5672 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5673 of ensuring that they are present (@pxref{Build Systems}).
5675 However, any other dependencies need to be specified in the
5676 @code{inputs} field. Any dependency not specified here will simply be
5677 unavailable to the build process, possibly leading to a build failure.
5680 @xref{package Reference}, for a full description of possible fields.
5682 Once a package definition is in place, the
5683 package may actually be built using the @code{guix build} command-line
5684 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5685 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5686 package definition using the @command{guix edit} command
5687 (@pxref{Invoking guix edit}).
5688 @xref{Packaging Guidelines}, for
5689 more information on how to test package definitions, and
5690 @ref{Invoking guix lint}, for information on how to check a definition
5691 for style conformance.
5692 @vindex GUIX_PACKAGE_PATH
5693 Lastly, @pxref{Channels}, for information
5694 on how to extend the distribution by adding your own package definitions
5697 Finally, updating the package definition to a new upstream version
5698 can be partly automated by the @command{guix refresh} command
5699 (@pxref{Invoking guix refresh}).
5701 Behind the scenes, a derivation corresponding to the @code{<package>}
5702 object is first computed by the @code{package-derivation} procedure.
5703 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
5704 The build actions it prescribes may then be realized by using the
5705 @code{build-derivations} procedure (@pxref{The Store}).
5707 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5708 Return the @code{<derivation>} object of @var{package} for @var{system}
5709 (@pxref{Derivations}).
5711 @var{package} must be a valid @code{<package>} object, and @var{system}
5712 must be a string denoting the target system type---e.g.,
5713 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5714 must be a connection to the daemon, which operates on the store
5715 (@pxref{The Store}).
5719 @cindex cross-compilation
5720 Similarly, it is possible to compute a derivation that cross-builds a
5721 package for some other system:
5723 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5724 @var{package} @var{target} [@var{system}]
5725 Return the @code{<derivation>} object of @var{package} cross-built from
5726 @var{system} to @var{target}.
5728 @var{target} must be a valid GNU triplet denoting the target hardware
5729 and operating system, such as @code{"aarch64-linux-gnu"}
5730 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5733 @cindex package transformations
5734 @cindex input rewriting
5735 @cindex dependency tree rewriting
5736 Packages can be manipulated in arbitrary ways. An example of a useful
5737 transformation is @dfn{input rewriting}, whereby the dependency tree of
5738 a package is rewritten by replacing specific inputs by others:
5740 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5741 [@var{rewrite-name}]
5742 Return a procedure that, when passed a package, replaces its direct and
5743 indirect dependencies (but not its implicit inputs) according to
5744 @var{replacements}. @var{replacements} is a list of package pairs; the
5745 first element of each pair is the package to replace, and the second one
5748 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5749 the name of a package and returns its new name after rewrite.
5753 Consider this example:
5756 (define libressl-instead-of-openssl
5757 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5759 (package-input-rewriting `((,openssl . ,libressl))))
5761 (define git-with-libressl
5762 (libressl-instead-of-openssl git))
5766 Here we first define a rewriting procedure that replaces @var{openssl}
5767 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5768 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5769 This is exactly what the @option{--with-input} command-line option does
5770 (@pxref{Package Transformation Options, @option{--with-input}}).
5772 The following variant of @code{package-input-rewriting} can match packages to
5773 be replaced by name rather than by identity.
5775 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5776 Return a procedure that, given a package, applies the given @var{replacements} to
5777 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5778 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5779 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5780 replacement for that package.
5783 The example above could be rewritten this way:
5786 (define libressl-instead-of-openssl
5787 ;; Replace all the packages called "openssl" with LibreSSL.
5788 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5791 The key difference here is that, this time, packages are matched by spec and
5792 not by identity. In other words, any package in the graph that is called
5793 @code{openssl} will be replaced.
5795 A more generic procedure to rewrite a package dependency graph is
5796 @code{package-mapping}: it supports arbitrary changes to nodes in the
5799 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5800 Return a procedure that, given a package, applies @var{proc} to all the packages
5801 depended on and returns the resulting package. The procedure stops recursion
5802 when @var{cut?} returns true for a given package.
5806 * package Reference:: The package data type.
5807 * origin Reference:: The origin data type.
5811 @node package Reference
5812 @subsection @code{package} Reference
5814 This section summarizes all the options available in @code{package}
5815 declarations (@pxref{Defining Packages}).
5817 @deftp {Data Type} package
5818 This is the data type representing a package recipe.
5822 The name of the package, as a string.
5824 @item @code{version}
5825 The version of the package, as a string.
5828 An object telling how the source code for the package should be
5829 acquired. Most of the time, this is an @code{origin} object, which
5830 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5831 can also be any other ``file-like'' object such as a @code{local-file},
5832 which denotes a file from the local file system (@pxref{G-Expressions,
5833 @code{local-file}}).
5835 @item @code{build-system}
5836 The build system that should be used to build the package (@pxref{Build
5839 @item @code{arguments} (default: @code{'()})
5840 The arguments that should be passed to the build system. This is a
5841 list, typically containing sequential keyword-value pairs.
5843 @item @code{inputs} (default: @code{'()})
5844 @itemx @code{native-inputs} (default: @code{'()})
5845 @itemx @code{propagated-inputs} (default: @code{'()})
5846 @cindex inputs, of packages
5847 These fields list dependencies of the package. Each one is a list of
5848 tuples, where each tuple has a label for the input (a string) as its
5849 first element, a package, origin, or derivation as its second element,
5850 and optionally the name of the output thereof that should be used, which
5851 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5852 more on package outputs). For example, the list below specifies three
5856 `(("libffi" ,libffi)
5857 ("libunistring" ,libunistring)
5858 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5861 @cindex cross compilation, package dependencies
5862 The distinction between @code{native-inputs} and @code{inputs} is
5863 necessary when considering cross-compilation. When cross-compiling,
5864 dependencies listed in @code{inputs} are built for the @emph{target}
5865 architecture; conversely, dependencies listed in @code{native-inputs}
5866 are built for the architecture of the @emph{build} machine.
5868 @code{native-inputs} is typically used to list tools needed at
5869 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5870 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5871 this area (@pxref{Invoking guix lint}).
5873 @anchor{package-propagated-inputs}
5874 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5875 specified packages will be automatically installed alongside the package
5876 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5877 package}}, for information on how @command{guix package} deals with
5880 For example this is necessary when a C/C++ library needs headers of
5881 another library to compile, or when a pkg-config file refers to another
5882 one @i{via} its @code{Requires} field.
5884 Another example where @code{propagated-inputs} is useful is for languages
5885 that lack a facility to record the run-time search path akin to the
5886 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5887 more. To ensure that libraries written in those languages can find
5888 library code they depend on at run time, run-time dependencies must be
5889 listed in @code{propagated-inputs} rather than @code{inputs}.
5891 @item @code{outputs} (default: @code{'("out")})
5892 The list of output names of the package. @xref{Packages with Multiple
5893 Outputs}, for typical uses of additional outputs.
5895 @item @code{native-search-paths} (default: @code{'()})
5896 @itemx @code{search-paths} (default: @code{'()})
5897 A list of @code{search-path-specification} objects describing
5898 search-path environment variables honored by the package.
5900 @item @code{replacement} (default: @code{#f})
5901 This must be either @code{#f} or a package object that will be used as a
5902 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5905 @item @code{synopsis}
5906 A one-line description of the package.
5908 @item @code{description}
5909 A more elaborate description of the package.
5911 @item @code{license}
5912 @cindex license, of packages
5913 The license of the package; a value from @code{(guix licenses)},
5914 or a list of such values.
5916 @item @code{home-page}
5917 The URL to the home-page of the package, as a string.
5919 @item @code{supported-systems} (default: @code{%supported-systems})
5920 The list of systems supported by the package, as strings of the form
5921 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5923 @item @code{location} (default: source location of the @code{package} form)
5924 The source location of the package. It is useful to override this when
5925 inheriting from another package, in which case this field is not
5926 automatically corrected.
5930 @deffn {Scheme Syntax} this-package
5931 When used in the @emph{lexical scope} of a package field definition, this
5932 identifier resolves to the package being defined.
5934 The example below shows how to add a package as a native input of itself when
5942 ;; When cross-compiled, Guile, for example, depends on
5943 ;; a native version of itself. Add it here.
5944 (native-inputs (if (%current-target-system)
5945 `(("self" ,this-package))
5949 It is an error to refer to @code{this-package} outside a package definition.
5952 @node origin Reference
5953 @subsection @code{origin} Reference
5955 This section summarizes all the options available in @code{origin}
5956 declarations (@pxref{Defining Packages}).
5958 @deftp {Data Type} origin
5959 This is the data type representing a source code origin.
5963 An object containing the URI of the source. The object type depends on
5964 the @code{method} (see below). For example, when using the
5965 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5966 values are: a URL represented as a string, or a list thereof.
5969 A procedure that handles the URI.
5974 @item @var{url-fetch} from @code{(guix download)}
5975 download a file from the HTTP, HTTPS, or FTP URL specified in the
5979 @item @var{git-fetch} from @code{(guix git-download)}
5980 clone the Git version control repository, and check out the revision
5981 specified in the @code{uri} field as a @code{git-reference} object; a
5982 @code{git-reference} looks like this:
5986 (url "https://git.savannah.gnu.org/git/hello.git")
5992 A bytevector containing the SHA-256 hash of the source. This is
5993 equivalent to providing a @code{content-hash} SHA256 object in the
5994 @code{hash} field described below.
5997 The @code{content-hash} object of the source---see below for how to use
5998 @code{content-hash}.
6000 You can obtain this information using @code{guix download}
6001 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6004 @item @code{file-name} (default: @code{#f})
6005 The file name under which the source code should be saved. When this is
6006 @code{#f}, a sensible default value will be used in most cases. In case
6007 the source is fetched from a URL, the file name from the URL will be
6008 used. For version control checkouts, it is recommended to provide the
6009 file name explicitly because the default is not very descriptive.
6011 @item @code{patches} (default: @code{'()})
6012 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6013 file-like objects}) pointing to patches to be applied to the source.
6015 This list of patches must be unconditional. In particular, it cannot
6016 depend on the value of @code{%current-system} or
6017 @code{%current-target-system}.
6019 @item @code{snippet} (default: @code{#f})
6020 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6021 in the source directory. This is a convenient way to modify the source,
6022 sometimes more convenient than a patch.
6024 @item @code{patch-flags} (default: @code{'("-p1")})
6025 A list of command-line flags that should be passed to the @code{patch}
6028 @item @code{patch-inputs} (default: @code{#f})
6029 Input packages or derivations to the patching process. When this is
6030 @code{#f}, the usual set of inputs necessary for patching are provided,
6031 such as GNU@tie{}Patch.
6033 @item @code{modules} (default: @code{'()})
6034 A list of Guile modules that should be loaded during the patching
6035 process and while running the code in the @code{snippet} field.
6037 @item @code{patch-guile} (default: @code{#f})
6038 The Guile package that should be used in the patching process. When
6039 this is @code{#f}, a sensible default is used.
6043 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6044 Construct a content hash object for the given @var{algorithm}, and with
6045 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6046 it is @code{sha256}.
6048 @var{value} can be a literal string, in which case it is base32-decoded,
6049 or it can be a bytevector.
6051 The following forms are all equivalent:
6054 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6055 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6057 (content-hash (base32
6058 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6059 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6063 Technically, @code{content-hash} is currently implemented as a macro.
6064 It performs sanity checks at macro-expansion time, when possible, such
6065 as ensuring that @var{value} has the right size for @var{algorithm}.
6069 @section Build Systems
6071 @cindex build system
6072 Each package definition specifies a @dfn{build system} and arguments for
6073 that build system (@pxref{Defining Packages}). This @code{build-system}
6074 field represents the build procedure of the package, as well as implicit
6075 dependencies of that build procedure.
6077 Build systems are @code{<build-system>} objects. The interface to
6078 create and manipulate them is provided by the @code{(guix build-system)}
6079 module, and actual build systems are exported by specific modules.
6081 @cindex bag (low-level package representation)
6082 Under the hood, build systems first compile package objects to
6083 @dfn{bags}. A @dfn{bag} is like a package, but with less
6084 ornamentation---in other words, a bag is a lower-level representation of
6085 a package, which includes all the inputs of that package, including some
6086 that were implicitly added by the build system. This intermediate
6087 representation is then compiled to a derivation (@pxref{Derivations}).
6089 Build systems accept an optional list of @dfn{arguments}. In package
6090 definitions, these are passed @i{via} the @code{arguments} field
6091 (@pxref{Defining Packages}). They are typically keyword arguments
6092 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
6093 Guile Reference Manual}). The value of these arguments is usually
6094 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
6095 by the daemon (@pxref{Derivations}).
6097 The main build system is @code{gnu-build-system}, which implements the
6098 standard build procedure for GNU and many other packages. It
6099 is provided by the @code{(guix build-system gnu)} module.
6101 @defvr {Scheme Variable} gnu-build-system
6102 @code{gnu-build-system} represents the GNU Build System, and variants
6103 thereof (@pxref{Configuration, configuration and makefile conventions,,
6104 standards, GNU Coding Standards}).
6106 @cindex build phases
6107 In a nutshell, packages using it are configured, built, and installed with
6108 the usual @code{./configure && make && make check && make install}
6109 command sequence. In practice, a few additional steps are often needed.
6110 All these steps are split up in separate @dfn{phases},
6111 notably@footnote{Please see the @code{(guix build gnu-build-system)}
6112 modules for more details about the build phases.}:
6116 Unpack the source tarball, and change the current directory to the
6117 extracted source tree. If the source is actually a directory, copy it
6118 to the build tree, and enter that directory.
6120 @item patch-source-shebangs
6121 Patch shebangs encountered in source files so they refer to the right
6122 store file names. For instance, this changes @code{#!/bin/sh} to
6123 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
6126 Run the @file{configure} script with a number of default options, such
6127 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
6128 by the @code{#:configure-flags} argument.
6131 Run @code{make} with the list of flags specified with
6132 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
6133 (the default), build with @code{make -j}.
6136 Run @code{make check}, or some other target specified with
6137 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
6138 @code{#:parallel-tests?} argument is true (the default), run @code{make
6142 Run @code{make install} with the flags listed in @code{#:make-flags}.
6144 @item patch-shebangs
6145 Patch shebangs on the installed executable files.
6148 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
6149 is false), copying them to the @code{debug} output when available
6150 (@pxref{Installing Debugging Files}).
6153 @vindex %standard-phases
6154 The build-side module @code{(guix build gnu-build-system)} defines
6155 @code{%standard-phases} as the default list of build phases.
6156 @code{%standard-phases} is a list of symbol/procedure pairs, where the
6157 procedure implements the actual phase.
6159 The list of phases used for a particular package can be changed with the
6160 @code{#:phases} parameter. For instance, passing:
6163 #:phases (modify-phases %standard-phases (delete 'configure))
6166 means that all the phases described above will be used, except the
6167 @code{configure} phase.
6169 In addition, this build system ensures that the ``standard'' environment
6170 for GNU packages is available. This includes tools such as GCC, libc,
6171 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
6172 build-system gnu)} module for a complete list). We call these the
6173 @dfn{implicit inputs} of a package, because package definitions do not
6174 have to mention them.
6177 Other @code{<build-system>} objects are defined to support other
6178 conventions and tools used by free software packages. They inherit most
6179 of @code{gnu-build-system}, and differ mainly in the set of inputs
6180 implicitly added to the build process, and in the list of phases
6181 executed. Some of these build systems are listed below.
6183 @defvr {Scheme Variable} ant-build-system
6184 This variable is exported by @code{(guix build-system ant)}. It
6185 implements the build procedure for Java packages that can be built with
6186 @url{https://ant.apache.org/, Ant build tool}.
6188 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
6189 provided by the @code{icedtea} package to the set of inputs. Different
6190 packages can be specified with the @code{#:ant} and @code{#:jdk}
6191 parameters, respectively.
6193 When the original package does not provide a suitable Ant build file,
6194 the parameter @code{#:jar-name} can be used to generate a minimal Ant
6195 build file @file{build.xml} with tasks to build the specified jar
6196 archive. In this case the parameter @code{#:source-dir} can be used to
6197 specify the source sub-directory, defaulting to ``src''.
6199 The @code{#:main-class} parameter can be used with the minimal ant
6200 buildfile to specify the main class of the resulting jar. This makes the
6201 jar file executable. The @code{#:test-include} parameter can be used to
6202 specify the list of junit tests to run. It defaults to
6203 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
6204 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
6205 because abstract classes cannot be run as tests.
6207 The parameter @code{#:build-target} can be used to specify the Ant task
6208 that should be run during the @code{build} phase. By default the
6209 ``jar'' task will be run.
6213 @defvr {Scheme Variable} android-ndk-build-system
6214 @cindex Android distribution
6215 @cindex Android NDK build system
6216 This variable is exported by @code{(guix build-system android-ndk)}. It
6217 implements a build procedure for Android NDK (native development kit)
6218 packages using a Guix-specific build process.
6220 The build system assumes that packages install their public interface
6221 (header) files to the subdirectory @file{include} of the @code{out} output and
6222 their libraries to the subdirectory @file{lib} the @code{out} output.
6224 It's also assumed that the union of all the dependencies of a package
6225 has no conflicting files.
6227 For the time being, cross-compilation is not supported - so right now
6228 the libraries and header files are assumed to be host tools.
6232 @defvr {Scheme Variable} asdf-build-system/source
6233 @defvrx {Scheme Variable} asdf-build-system/sbcl
6234 @defvrx {Scheme Variable} asdf-build-system/ecl
6236 These variables, exported by @code{(guix build-system asdf)}, implement
6237 build procedures for Common Lisp packages using
6238 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
6239 definition facility for Common Lisp programs and libraries.
6241 The @code{asdf-build-system/source} system installs the packages in
6242 source form, and can be loaded using any common lisp implementation, via
6243 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
6244 systems in the format which a particular implementation understands.
6245 These build systems can also be used to produce executable programs, or
6246 lisp images which contain a set of packages pre-loaded.
6248 The build system uses naming conventions. For binary packages, the
6249 package name should be prefixed with the lisp implementation, such as
6250 @code{sbcl-} for @code{asdf-build-system/sbcl}.
6252 Additionally, the corresponding source package should be labeled using
6253 the same convention as python packages (see @ref{Python Modules}), using
6254 the @code{cl-} prefix.
6256 For binary packages, each system should be defined as a Guix package.
6257 If one package @code{origin} contains several systems, package variants
6258 can be created in order to build all the systems. Source packages,
6259 which use @code{asdf-build-system/source}, may contain several systems.
6261 In order to create executable programs and images, the build-side
6262 procedures @code{build-program} and @code{build-image} can be used.
6263 They should be called in a build phase after the @code{create-symlinks}
6264 phase, so that the system which was just built can be used within the
6265 resulting image. @code{build-program} requires a list of Common Lisp
6266 expressions to be passed as the @code{#:entry-program} argument.
6268 If the system is not defined within its own @file{.asd} file of the same
6269 name, then the @code{#:asd-file} parameter should be used to specify
6270 which file the system is defined in. Furthermore, if the package
6271 defines a system for its tests in a separate file, it will be loaded
6272 before the tests are run if it is specified by the
6273 @code{#:test-asd-file} parameter. If it is not set, the files
6274 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
6275 and @code{test.asd} will be tried if they exist.
6277 If for some reason the package must be named in a different way than the
6278 naming conventions suggest, the @code{#:asd-system-name} parameter can
6279 be used to specify the name of the system.
6283 @defvr {Scheme Variable} cargo-build-system
6284 @cindex Rust programming language
6285 @cindex Cargo (Rust build system)
6286 This variable is exported by @code{(guix build-system cargo)}. It
6287 supports builds of packages using Cargo, the build tool of the
6288 @uref{https://www.rust-lang.org, Rust programming language}.
6290 It adds @code{rustc} and @code{cargo} to the set of inputs.
6291 A different Rust package can be specified with the @code{#:rust} parameter.
6293 Regular cargo dependencies should be added to the package definition via the
6294 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
6295 spec can be a package or a source definition. Note that the spec must
6296 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
6297 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
6298 should be added to the package definition via the
6299 @code{#:cargo-development-inputs} parameter.
6301 In its @code{configure} phase, this build system will make any source inputs
6302 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6303 parameters available to cargo. It will also remove an included
6304 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6305 @code{build} phase. The @code{install} phase installs any crate the binaries
6306 if they are defined by the crate.
6310 @defvr {Scheme Variable} copy-build-system
6311 This variable is exported by @code{(guix build-system copy)}. It
6312 supports builds of simple packages that don't require much compiling,
6313 mostly just moving files around.
6315 It adds much of the @code{gnu-build-system} packages to the set of
6316 inputs. Because of this, the @code{copy-build-system} does not require
6317 all the boilerplate code often needed for the
6318 @code{trivial-build-system}.
6320 To further simplify the file installation process, an
6321 @code{#:install-plan} argument is exposed to let the packager specify
6322 which files go where. The install plan is a list of @code{(@var{source}
6323 @var{target} [@var{filters}])}. @var{filters} are optional.
6326 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
6328 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
6329 @item Otherwise install @var{source} as @var{target}.
6332 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
6333 the trailing slash of @var{target} is implied with the same meaning
6336 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
6337 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
6338 @code{#:exclude-regexp}, only select files are installed depending on
6339 the filters. Each filters is specified by a list of strings.
6341 @item With @code{#:include}, install all the files which the path suffix matches
6342 at least one of the elements in the given list.
6343 @item With @code{#:include-regexp}, install all the files which the
6344 subpaths match at least one of the regular expressions in the given
6346 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
6347 are the complement of their inclusion counterpart. Without @code{#:include} flags,
6348 install all files but those matching the exclusion filters.
6349 If both inclusions and exclusions are specified, the exclusions are done
6350 on top of the inclusions.
6353 In all cases, the paths relative to @var{source} are preserved within
6360 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
6361 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
6362 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
6363 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
6364 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
6365 @file{share/my-app/sub/file}.
6366 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
6367 @file{share/my-app/file}.
6372 @cindex Clojure (programming language)
6373 @cindex simple Clojure build system
6374 @defvr {Scheme Variable} clojure-build-system
6375 This variable is exported by @code{(guix build-system clojure)}. It implements
6376 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6377 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6380 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6381 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6382 @code{#:zip} parameters, respectively.
6384 A list of source directories, test directories and jar names can be specified
6385 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6386 parameters, respectively. Compile directory and main class can be specified
6387 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6388 Other parameters are documented below.
6390 This build system is an extension of @code{ant-build-system}, but with the
6391 following phases changed:
6396 This phase calls @code{compile} in Clojure to compile source files and runs
6397 @command{jar} to create jars from both source files and compiled files
6398 according to the include list and exclude list specified in
6399 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6400 has priority over the include list. These lists consist of symbols
6401 representing Clojure libraries or the special keyword @code{#:all} representing
6402 all Clojure libraries found under the source directories. The parameter
6403 @code{#:omit-source?} decides if source should be included into the jars.
6406 This phase runs tests according to the include list and exclude list specified
6407 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6408 meanings are analogous to that of @code{#:aot-include} and
6409 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6410 stands for all Clojure libraries found under the test directories. The
6411 parameter @code{#:tests?} decides if tests should be run.
6414 This phase installs all jars built previously.
6417 Apart from the above, this build system also contains an additional phase:
6422 This phase installs all top-level files with base name matching
6423 @code{%doc-regex}. A different regex can be specified with the
6424 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6425 directories specified in @code{#:doc-dirs} are installed as well.
6429 @defvr {Scheme Variable} cmake-build-system
6430 This variable is exported by @code{(guix build-system cmake)}. It
6431 implements the build procedure for packages using the
6432 @url{https://www.cmake.org, CMake build tool}.
6434 It automatically adds the @code{cmake} package to the set of inputs.
6435 Which package is used can be specified with the @code{#:cmake}
6438 The @code{#:configure-flags} parameter is taken as a list of flags
6439 passed to the @command{cmake} command. The @code{#:build-type}
6440 parameter specifies in abstract terms the flags passed to the compiler;
6441 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6442 debugging information''), which roughly means that code is compiled with
6443 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6446 @defvr {Scheme Variable} dune-build-system
6447 This variable is exported by @code{(guix build-system dune)}. It
6448 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6449 tool for the OCaml programming language. It is implemented as an extension
6450 of the @code{ocaml-build-system} which is described below. As such, the
6451 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6454 It automatically adds the @code{dune} package to the set of inputs.
6455 Which package is used can be specified with the @code{#:dune}
6458 There is no @code{configure} phase because dune packages typically don't
6459 need to be configured. The @code{#:build-flags} parameter is taken as a
6460 list of flags passed to the @code{dune} command during the build.
6462 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6463 command instead of the more recent @code{dune} command while building
6464 a package. Its default value is @code{#f}.
6466 The @code{#:package} parameter can be passed to specify a package name, which
6467 is useful when a package contains multiple packages and you want to build
6468 only one of them. This is equivalent to passing the @code{-p} argument to
6472 @defvr {Scheme Variable} go-build-system
6473 This variable is exported by @code{(guix build-system go)}. It
6474 implements a build procedure for Go packages using the standard
6475 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6476 Go build mechanisms}.
6478 The user is expected to provide a value for the key @code{#:import-path}
6479 and, in some cases, @code{#:unpack-path}. The
6480 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6481 corresponds to the file system path expected by the package's build
6482 scripts and any referring packages, and provides a unique way to
6483 refer to a Go package. It is typically based on a combination of the
6484 package source code's remote URI and file system hierarchy structure. In
6485 some cases, you will need to unpack the package's source code to a
6486 different directory structure than the one indicated by the import path,
6487 and @code{#:unpack-path} should be used in such cases.
6489 Packages that provide Go libraries should install their source code into
6490 the built output. The key @code{#:install-source?}, which defaults to
6491 @code{#t}, controls whether or not the source code is installed. It can
6492 be set to @code{#f} for packages that only provide executable files.
6495 @defvr {Scheme Variable} glib-or-gtk-build-system
6496 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6497 is intended for use with packages making use of GLib or GTK+.
6499 This build system adds the following two phases to the ones defined by
6500 @code{gnu-build-system}:
6503 @item glib-or-gtk-wrap
6504 The phase @code{glib-or-gtk-wrap} ensures that programs in
6505 @file{bin/} are able to find GLib ``schemas'' and
6506 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6507 modules}. This is achieved by wrapping the programs in launch scripts
6508 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
6509 environment variables.
6511 It is possible to exclude specific package outputs from that wrapping
6512 process by listing their names in the
6513 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6514 when an output is known not to contain any GLib or GTK+ binaries, and
6515 where wrapping would gratuitously add a dependency of that output on
6518 @item glib-or-gtk-compile-schemas
6519 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6520 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6521 GSettings schemas} of GLib are compiled. Compilation is performed by the
6522 @command{glib-compile-schemas} program. It is provided by the package
6523 @code{glib:bin} which is automatically imported by the build system.
6524 The @code{glib} package providing @command{glib-compile-schemas} can be
6525 specified with the @code{#:glib} parameter.
6528 Both phases are executed after the @code{install} phase.
6531 @defvr {Scheme Variable} guile-build-system
6532 This build system is for Guile packages that consist exclusively of Scheme
6533 code and that are so lean that they don't even have a makefile, let alone a
6534 @file{configure} script. It compiles Scheme code using @command{guild
6535 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6536 installs the @file{.scm} and @file{.go} files in the right place. It also
6537 installs documentation.
6539 This build system supports cross-compilation by using the
6540 @option{--target} option of @samp{guild compile}.
6542 Packages built with @code{guile-build-system} must provide a Guile package in
6543 their @code{native-inputs} field.
6546 @defvr {Scheme Variable} julia-build-system
6547 This variable is exported by @code{(guix build-system julia)}. It
6548 implements the build procedure used by @uref{https://julialang.org/,
6549 julia} packages, which essentially is similar to running @samp{julia -e
6550 'using Pkg; Pkg.add(package)'} in an environment where
6551 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
6552 Tests are run not run.
6554 Julia packages require the source @code{file-name} to be the real name of the
6555 package, correctly capitalized.
6557 For packages requiring shared library dependencies, you may need to write the
6558 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6559 variable = /gnu/store/library.so} for each dependency, plus a void function
6560 @code{check_deps() = nothing}.
6562 Some older packages that aren't using @file{Package.toml} yet, will require
6563 this file to be created, too. The function @code{julia-create-package-toml}
6564 helps creating the file. You need to pass the outputs and the source of the
6565 package, it's name (the same as the @code{file-name} parameter), the package
6566 uuid, the package version, and a list of dependencies specified by their name
6570 @defvr {Scheme Variable} minify-build-system
6571 This variable is exported by @code{(guix build-system minify)}. It
6572 implements a minification procedure for simple JavaScript packages.
6574 It adds @code{uglify-js} to the set of inputs and uses it to compress
6575 all JavaScript files in the @file{src} directory. A different minifier
6576 package can be specified with the @code{#:uglify-js} parameter, but it
6577 is expected that the package writes the minified code to the standard
6580 When the input JavaScript files are not all located in the @file{src}
6581 directory, the parameter @code{#:javascript-files} can be used to
6582 specify a list of file names to feed to the minifier.
6585 @defvr {Scheme Variable} ocaml-build-system
6586 This variable is exported by @code{(guix build-system ocaml)}. It implements
6587 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6588 of choosing the correct set of commands to run for each package. OCaml
6589 packages can expect many different commands to be run. This build system will
6592 When the package has a @file{setup.ml} file present at the top-level, it will
6593 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6594 @code{ocaml setup.ml -install}. The build system will assume that this file
6595 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6596 care of setting the prefix and enabling tests if they are not disabled. You
6597 can pass configure and build flags with the @code{#:configure-flags} and
6598 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6599 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6600 bypass this system in the build and install phases.
6602 When the package has a @file{configure} file, it is assumed that it is a
6603 hand-made configure script that requires a different argument format than
6604 in the @code{gnu-build-system}. You can add more flags with the
6605 @code{#:configure-flags} key.
6607 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6608 @code{#t}), it will be used and more flags can be passed to the build and
6609 install phases with the @code{#:make-flags} key.
6611 Finally, some packages do not have these files and use a somewhat standard
6612 location for its build system. In that case, the build system will run
6613 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6614 providing the path to the required findlib module. Additional flags can
6615 be passed via the @code{#:build-flags} key. Install is taken care of by
6616 @command{opam-installer}. In this case, the @code{opam} package must
6617 be added to the @code{native-inputs} field of the package definition.
6619 Note that most OCaml packages assume they will be installed in the same
6620 directory as OCaml, which is not what we want in guix. In particular, they
6621 will install @file{.so} files in their module's directory, which is usually
6622 fine because it is in the OCaml compiler directory. In guix though, these
6623 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
6624 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6625 @file{.so} libraries should be installed.
6628 @defvr {Scheme Variable} python-build-system
6629 This variable is exported by @code{(guix build-system python)}. It
6630 implements the more or less standard build procedure used by Python
6631 packages, which consists in running @code{python setup.py build} and
6632 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6634 For packages that install stand-alone Python programs under @code{bin/},
6635 it takes care of wrapping these programs so that their @env{PYTHONPATH}
6636 environment variable points to all the Python libraries they depend on.
6638 Which Python package is used to perform the build can be specified with
6639 the @code{#:python} parameter. This is a useful way to force a package
6640 to be built for a specific version of the Python interpreter, which
6641 might be necessary if the package is only compatible with a single
6642 interpreter version.
6644 By default guix calls @code{setup.py} under control of
6645 @code{setuptools}, much like @command{pip} does. Some packages are not
6646 compatible with setuptools (and pip), thus you can disable this by
6647 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6650 @defvr {Scheme Variable} perl-build-system
6651 This variable is exported by @code{(guix build-system perl)}. It
6652 implements the standard build procedure for Perl packages, which either
6653 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6654 followed by @code{Build} and @code{Build install}; or in running
6655 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6656 @code{make} and @code{make install}, depending on which of
6657 @code{Build.PL} or @code{Makefile.PL} is present in the package
6658 distribution. Preference is given to the former if both @code{Build.PL}
6659 and @code{Makefile.PL} exist in the package distribution. This
6660 preference can be reversed by specifying @code{#t} for the
6661 @code{#:make-maker?} parameter.
6663 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6664 passes flags specified by the @code{#:make-maker-flags} or
6665 @code{#:module-build-flags} parameter, respectively.
6667 Which Perl package is used can be specified with @code{#:perl}.
6670 @defvr {Scheme Variable} qt-build-system
6671 This variable is exported by @code{(guix build-system qt)}. It
6672 is intended for use with applications using Qt or KDE.
6674 This build system adds the following two phases to the ones defined by
6675 @code{cmake-build-system}:
6679 The phase @code{check-setup} prepares the environment for running
6680 the checks as commonly used by Qt test programs.
6681 For now this only sets some environment variables:
6682 @code{QT_QPA_PLATFORM=offscreen},
6683 @code{DBUS_FATAL_WARNINGS=0} and
6684 @code{CTEST_OUTPUT_ON_FAILURE=1}.
6686 This phase is added before the @code{check} phase.
6687 It's a separate phase to ease adjusting if necessary.
6690 The phase @code{qt-wrap}
6691 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
6692 and output. In case some path is found, all programs in the output's
6693 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
6694 are wrapped in scripts defining the necessary environment variables.
6696 It is possible to exclude specific package outputs from that wrapping process
6697 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
6698 This is useful when an output is known not to contain any Qt binaries, and
6699 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
6702 This phase is added after the @code{install} phase.
6706 @defvr {Scheme Variable} r-build-system
6707 This variable is exported by @code{(guix build-system r)}. It
6708 implements the build procedure used by @uref{https://r-project.org, R}
6709 packages, which essentially is little more than running @samp{R CMD
6710 INSTALL --library=/gnu/store/@dots{}} in an environment where
6711 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
6712 run after installation using the R function
6713 @code{tools::testInstalledPackage}.
6716 @defvr {Scheme Variable} rakudo-build-system
6717 This variable is exported by @code{(guix build-system rakudo)}. It
6718 implements the build procedure used by @uref{https://rakudo.org/,
6719 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6720 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6721 installs the binaries, library files and the resources, as well as wrap
6722 the files under the @code{bin/} directory. Tests can be skipped by
6723 passing @code{#f} to the @code{tests?} parameter.
6725 Which rakudo package is used can be specified with @code{rakudo}.
6726 Which perl6-tap-harness package used for the tests can be specified with
6727 @code{#:prove6} or removed by passing @code{#f} to the
6728 @code{with-prove6?} parameter.
6729 Which perl6-zef package used for tests and installing can be specified
6730 with @code{#:zef} or removed by passing @code{#f} to the
6731 @code{with-zef?} parameter.
6734 @defvr {Scheme Variable} texlive-build-system
6735 This variable is exported by @code{(guix build-system texlive)}. It is
6736 used to build TeX packages in batch mode with a specified engine. The
6737 build system sets the @env{TEXINPUTS} variable to find all TeX source
6738 files in the inputs.
6740 By default it runs @code{luatex} on all files ending on @code{ins}. A
6741 different engine and format can be specified with the
6742 @code{#:tex-format} argument. Different build targets can be specified
6743 with the @code{#:build-targets} argument, which expects a list of file
6744 names. The build system adds only @code{texlive-bin} and
6745 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6746 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6747 and @code{#:texlive-latex-base}, respectively.
6749 The @code{#:tex-directory} parameter tells the build system where to
6750 install the built files under the texmf tree.
6753 @defvr {Scheme Variable} ruby-build-system
6754 This variable is exported by @code{(guix build-system ruby)}. It
6755 implements the RubyGems build procedure used by Ruby packages, which
6756 involves running @code{gem build} followed by @code{gem install}.
6758 The @code{source} field of a package that uses this build system
6759 typically references a gem archive, since this is the format that Ruby
6760 developers use when releasing their software. The build system unpacks
6761 the gem archive, potentially patches the source, runs the test suite,
6762 repackages the gem, and installs it. Additionally, directories and
6763 tarballs may be referenced to allow building unreleased gems from Git or
6764 a traditional source release tarball.
6766 Which Ruby package is used can be specified with the @code{#:ruby}
6767 parameter. A list of additional flags to be passed to the @command{gem}
6768 command can be specified with the @code{#:gem-flags} parameter.
6771 @defvr {Scheme Variable} waf-build-system
6772 This variable is exported by @code{(guix build-system waf)}. It
6773 implements a build procedure around the @code{waf} script. The common
6774 phases---@code{configure}, @code{build}, and @code{install}---are
6775 implemented by passing their names as arguments to the @code{waf}
6778 The @code{waf} script is executed by the Python interpreter. Which
6779 Python package is used to run the script can be specified with the
6780 @code{#:python} parameter.
6783 @defvr {Scheme Variable} scons-build-system
6784 This variable is exported by @code{(guix build-system scons)}. It
6785 implements the build procedure used by the SCons software construction
6786 tool. This build system runs @code{scons} to build the package,
6787 @code{scons test} to run tests, and then @code{scons install} to install
6790 Additional flags to be passed to @code{scons} can be specified with the
6791 @code{#:scons-flags} parameter. The default build and install targets
6792 can be overridden with @code{#:build-targets} and
6793 @code{#:install-targets} respectively. The version of Python used to
6794 run SCons can be specified by selecting the appropriate SCons package
6795 with the @code{#:scons} parameter.
6798 @defvr {Scheme Variable} haskell-build-system
6799 This variable is exported by @code{(guix build-system haskell)}. It
6800 implements the Cabal build procedure used by Haskell packages, which
6801 involves running @code{runhaskell Setup.hs configure
6802 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6803 Instead of installing the package by running @code{runhaskell Setup.hs
6804 install}, to avoid trying to register libraries in the read-only
6805 compiler store directory, the build system uses @code{runhaskell
6806 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6807 addition, the build system generates the package documentation by
6808 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6809 is passed. Optional Haddock parameters can be passed with the help of
6810 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6811 not found, the build system looks for @code{Setup.lhs} instead.
6813 Which Haskell compiler is used can be specified with the @code{#:haskell}
6814 parameter which defaults to @code{ghc}.
6817 @defvr {Scheme Variable} dub-build-system
6818 This variable is exported by @code{(guix build-system dub)}. It
6819 implements the Dub build procedure used by D packages, which
6820 involves running @code{dub build} and @code{dub run}.
6821 Installation is done by copying the files manually.
6823 Which D compiler is used can be specified with the @code{#:ldc}
6824 parameter which defaults to @code{ldc}.
6827 @defvr {Scheme Variable} emacs-build-system
6828 This variable is exported by @code{(guix build-system emacs)}. It
6829 implements an installation procedure similar to the packaging system
6830 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6832 It first creates the @code{@code{package}-autoloads.el} file, then it
6833 byte compiles all Emacs Lisp files. Differently from the Emacs
6834 packaging system, the Info documentation files are moved to the standard
6835 documentation directory and the @file{dir} file is deleted. The Elisp
6836 package files are installed directly under @file{share/emacs/site-lisp}.
6839 @defvr {Scheme Variable} font-build-system
6840 This variable is exported by @code{(guix build-system font)}. It
6841 implements an installation procedure for font packages where upstream
6842 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6843 need to be copied into place. It copies font files to standard
6844 locations in the output directory.
6847 @defvr {Scheme Variable} meson-build-system
6848 This variable is exported by @code{(guix build-system meson)}. It
6849 implements the build procedure for packages that use
6850 @url{https://mesonbuild.com, Meson} as their build system.
6852 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6853 of inputs, and they can be changed with the parameters @code{#:meson}
6854 and @code{#:ninja} if needed. The default Meson is
6855 @code{meson-for-build}, which is special because it doesn't clear the
6856 @code{RUNPATH} of binaries and libraries when they are installed.
6858 This build system is an extension of @code{gnu-build-system}, but with the
6859 following phases changed to some specific for Meson:
6864 The phase runs @code{meson} with the flags specified in
6865 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
6866 @code{debugoptimized} unless something else is specified in
6867 @code{#:build-type}.
6870 The phase runs @code{ninja} to build the package in parallel by default, but
6871 this can be changed with @code{#:parallel-build?}.
6874 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6875 which is @code{"test"} by default.
6878 The phase runs @code{ninja install} and can not be changed.
6881 Apart from that, the build system also adds the following phases:
6886 This phase ensures that all binaries can find the libraries they need.
6887 It searches for required libraries in subdirectories of the package being
6888 built, and adds those to @code{RUNPATH} where needed. It also removes
6889 references to libraries left over from the build phase by
6890 @code{meson-for-build}, such as test dependencies, that aren't actually
6891 required for the program to run.
6893 @item glib-or-gtk-wrap
6894 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6895 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6897 @item glib-or-gtk-compile-schemas
6898 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6899 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6903 @defvr {Scheme Variable} linux-module-build-system
6904 @code{linux-module-build-system} allows building Linux kernel modules.
6906 @cindex build phases
6907 This build system is an extension of @code{gnu-build-system}, but with the
6908 following phases changed:
6913 This phase configures the environment so that the Linux kernel's Makefile
6914 can be used to build the external kernel module.
6917 This phase uses the Linux kernel's Makefile in order to build the external
6921 This phase uses the Linux kernel's Makefile in order to install the external
6925 It is possible and useful to specify the Linux kernel to use for building
6926 the module (in the @code{arguments} form of a package using the
6927 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
6930 @defvr {Scheme Variable} node-build-system
6931 This variable is exported by @code{(guix build-system node)}. It
6932 implements the build procedure used by @uref{https://nodejs.org,
6933 Node.js}, which implements an approximation of the @code{npm install}
6934 command, followed by an @code{npm test} command.
6936 Which Node.js package is used to interpret the @code{npm} commands can
6937 be specified with the @code{#:node} parameter which defaults to
6941 Lastly, for packages that do not need anything as sophisticated, a
6942 ``trivial'' build system is provided. It is trivial in the sense that
6943 it provides basically no support: it does not pull any implicit inputs,
6944 and does not have a notion of build phases.
6946 @defvr {Scheme Variable} trivial-build-system
6947 This variable is exported by @code{(guix build-system trivial)}.
6949 This build system requires a @code{#:builder} argument. This argument
6950 must be a Scheme expression that builds the package output(s)---as
6951 with @code{build-expression->derivation} (@pxref{Derivations,
6952 @code{build-expression->derivation}}).
6962 Conceptually, the @dfn{store} is the place where derivations that have
6963 been built successfully are stored---by default, @file{/gnu/store}.
6964 Sub-directories in the store are referred to as @dfn{store items} or
6965 sometimes @dfn{store paths}. The store has an associated database that
6966 contains information such as the store paths referred to by each store
6967 path, and the list of @emph{valid} store items---results of successful
6968 builds. This database resides in @file{@var{localstatedir}/guix/db},
6969 where @var{localstatedir} is the state directory specified @i{via}
6970 @option{--localstatedir} at configure time, usually @file{/var}.
6972 The store is @emph{always} accessed by the daemon on behalf of its clients
6973 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6974 connect to the daemon over a Unix-domain socket, send requests to it,
6975 and read the result---these are remote procedure calls, or RPCs.
6978 Users must @emph{never} modify files under @file{/gnu/store} directly.
6979 This would lead to inconsistencies and break the immutability
6980 assumptions of Guix's functional model (@pxref{Introduction}).
6982 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6983 how to check the integrity of the store and attempt recovery from
6984 accidental modifications.
6987 The @code{(guix store)} module provides procedures to connect to the
6988 daemon, and to perform RPCs. These are described below. By default,
6989 @code{open-connection}, and thus all the @command{guix} commands,
6990 connect to the local daemon or to the URI specified by the
6991 @env{GUIX_DAEMON_SOCKET} environment variable.
6993 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6994 When set, the value of this variable should be a file name or a URI
6995 designating the daemon endpoint. When it is a file name, it denotes a
6996 Unix-domain socket to connect to. In addition to file names, the
6997 supported URI schemes are:
7002 These are for Unix-domain sockets.
7003 @code{file:///var/guix/daemon-socket/socket} is equivalent to
7004 @file{/var/guix/daemon-socket/socket}.
7007 @cindex daemon, remote access
7008 @cindex remote access to the daemon
7009 @cindex daemon, cluster setup
7010 @cindex clusters, daemon setup
7011 These URIs denote connections over TCP/IP, without encryption nor
7012 authentication of the remote host. The URI must specify the host name
7013 and optionally a port number (by default port 44146 is used):
7016 guix://master.guix.example.org:1234
7019 This setup is suitable on local networks, such as clusters, where only
7020 trusted nodes may connect to the build daemon at
7021 @code{master.guix.example.org}.
7023 The @option{--listen} option of @command{guix-daemon} can be used to
7024 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
7025 @option{--listen}}).
7028 @cindex SSH access to build daemons
7029 These URIs allow you to connect to a remote daemon over SSH. This
7030 feature requires Guile-SSH (@pxref{Requirements}) and a working
7031 @command{guile} binary in @env{PATH} on the destination machine. It
7032 supports public key and GSSAPI authentication. A typical URL might look
7036 ssh://charlie@@guix.example.org:22
7039 As for @command{guix copy}, the usual OpenSSH client configuration files
7040 are honored (@pxref{Invoking guix copy}).
7043 Additional URI schemes may be supported in the future.
7045 @c XXX: Remove this note when the protocol incurs fewer round trips
7046 @c and when (guix derivations) no longer relies on file system access.
7048 The ability to connect to remote build daemons is considered
7049 experimental as of @value{VERSION}. Please get in touch with us to
7050 share any problems or suggestions you may have (@pxref{Contributing}).
7054 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
7055 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
7056 @var{reserve-space?} is true, instruct it to reserve a little bit of
7057 extra space on the file system so that the garbage collector can still
7058 operate should the disk become full. Return a server object.
7060 @var{file} defaults to @code{%default-socket-path}, which is the normal
7061 location given the options that were passed to @command{configure}.
7064 @deffn {Scheme Procedure} close-connection @var{server}
7065 Close the connection to @var{server}.
7068 @defvr {Scheme Variable} current-build-output-port
7069 This variable is bound to a SRFI-39 parameter, which refers to the port
7070 where build and error logs sent by the daemon should be written.
7073 Procedures that make RPCs all take a server object as their first
7076 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
7077 @cindex invalid store items
7078 Return @code{#t} when @var{path} designates a valid store item and
7079 @code{#f} otherwise (an invalid item may exist on disk but still be
7080 invalid, for instance because it is the result of an aborted or failed
7083 A @code{&store-protocol-error} condition is raised if @var{path} is not
7084 prefixed by the store directory (@file{/gnu/store}).
7087 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
7088 Add @var{text} under file @var{name} in the store, and return its store
7089 path. @var{references} is the list of store paths referred to by the
7090 resulting store path.
7093 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
7095 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
7096 file names, or derivation/output pairs, using the specified
7097 @var{mode}---@code{(build-mode normal)} by default.
7100 Note that the @code{(guix monads)} module provides a monad as well as
7101 monadic versions of the above procedures, with the goal of making it
7102 more convenient to work with code that accesses the store (@pxref{The
7106 @i{This section is currently incomplete.}
7109 @section Derivations
7112 Low-level build actions and the environment in which they are performed
7113 are represented by @dfn{derivations}. A derivation contains the
7114 following pieces of information:
7118 The outputs of the derivation---derivations produce at least one file or
7119 directory in the store, but may produce more.
7122 @cindex build-time dependencies
7123 @cindex dependencies, build-time
7124 The inputs of the derivations---i.e., its build-time dependencies---which may
7125 be other derivations or plain files in the store (patches, build scripts,
7129 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
7132 The file name of a build script in the store, along with the arguments
7136 A list of environment variables to be defined.
7140 @cindex derivation path
7141 Derivations allow clients of the daemon to communicate build actions to
7142 the store. They exist in two forms: as an in-memory representation,
7143 both on the client- and daemon-side, and as files in the store whose
7144 name end in @file{.drv}---these files are referred to as @dfn{derivation
7145 paths}. Derivations paths can be passed to the @code{build-derivations}
7146 procedure to perform the build actions they prescribe (@pxref{The
7149 @cindex fixed-output derivations
7150 Operations such as file downloads and version-control checkouts for
7151 which the expected content hash is known in advance are modeled as
7152 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
7153 of a fixed-output derivation are independent of its inputs---e.g., a
7154 source code download produces the same result regardless of the download
7155 method and tools being used.
7158 @cindex run-time dependencies
7159 @cindex dependencies, run-time
7160 The outputs of derivations---i.e., the build results---have a set of
7161 @dfn{references}, as reported by the @code{references} RPC or the
7162 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
7163 are the set of run-time dependencies of the build results. References are a
7164 subset of the inputs of the derivation; this subset is automatically computed
7165 by the build daemon by scanning all the files in the outputs.
7167 The @code{(guix derivations)} module provides a representation of
7168 derivations as Scheme objects, along with procedures to create and
7169 otherwise manipulate derivations. The lowest-level primitive to create
7170 a derivation is the @code{derivation} procedure:
7172 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
7173 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7174 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
7175 [#:system (%current-system)] [#:references-graphs #f] @
7176 [#:allowed-references #f] [#:disallowed-references #f] @
7177 [#:leaked-env-vars #f] [#:local-build? #f] @
7178 [#:substitutable? #t] [#:properties '()]
7179 Build a derivation with the given arguments, and return the resulting
7180 @code{<derivation>} object.
7182 When @var{hash} and @var{hash-algo} are given, a
7183 @dfn{fixed-output derivation} is created---i.e., one whose result is
7184 known in advance, such as a file download. If, in addition,
7185 @var{recursive?} is true, then that fixed output may be an executable
7186 file or a directory and @var{hash} must be the hash of an archive
7187 containing this output.
7189 When @var{references-graphs} is true, it must be a list of file
7190 name/store path pairs. In that case, the reference graph of each store
7191 path is exported in the build environment in the corresponding file, in
7192 a simple text format.
7194 When @var{allowed-references} is true, it must be a list of store items
7195 or outputs that the derivation's output may refer to. Likewise,
7196 @var{disallowed-references}, if true, must be a list of things the
7197 outputs may @emph{not} refer to.
7199 When @var{leaked-env-vars} is true, it must be a list of strings
7200 denoting environment variables that are allowed to ``leak'' from the
7201 daemon's environment to the build environment. This is only applicable
7202 to fixed-output derivations---i.e., when @var{hash} is true. The main
7203 use is to allow variables such as @code{http_proxy} to be passed to
7204 derivations that download files.
7206 When @var{local-build?} is true, declare that the derivation is not a
7207 good candidate for offloading and should rather be built locally
7208 (@pxref{Daemon Offload Setup}). This is the case for small derivations
7209 where the costs of data transfers would outweigh the benefits.
7211 When @var{substitutable?} is false, declare that substitutes of the
7212 derivation's output should not be used (@pxref{Substitutes}). This is
7213 useful, for instance, when building packages that capture details of the
7214 host CPU instruction set.
7216 @var{properties} must be an association list describing ``properties'' of the
7217 derivation. It is kept as-is, uninterpreted, in the derivation.
7221 Here's an example with a shell script as its builder, assuming
7222 @var{store} is an open connection to the daemon, and @var{bash} points
7223 to a Bash executable in the store:
7226 (use-modules (guix utils)
7230 (let ((builder ; add the Bash script to the store
7231 (add-text-to-store store "my-builder.sh"
7232 "echo hello world > $out\n" '())))
7233 (derivation store "foo"
7234 bash `("-e" ,builder)
7235 #:inputs `((,bash) (,builder))
7236 #:env-vars '(("HOME" . "/homeless"))))
7237 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
7240 As can be guessed, this primitive is cumbersome to use directly. A
7241 better approach is to write build scripts in Scheme, of course! The
7242 best course of action for that is to write the build code as a
7243 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
7244 information, @pxref{G-Expressions}.
7246 Once upon a time, @code{gexp->derivation} did not exist and constructing
7247 derivations with build code written in Scheme was achieved with
7248 @code{build-expression->derivation}, documented below. This procedure
7249 is now deprecated in favor of the much nicer @code{gexp->derivation}.
7251 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
7252 @var{name} @var{exp} @
7253 [#:system (%current-system)] [#:inputs '()] @
7254 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7255 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7256 [#:references-graphs #f] [#:allowed-references #f] @
7257 [#:disallowed-references #f] @
7258 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
7259 Return a derivation that executes Scheme expression @var{exp} as a
7260 builder for derivation @var{name}. @var{inputs} must be a list of
7261 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
7262 @code{"out"} is assumed. @var{modules} is a list of names of Guile
7263 modules from the current search path to be copied in the store,
7264 compiled, and made available in the load path during the execution of
7265 @var{exp}---e.g., @code{((guix build utils) (guix build
7266 gnu-build-system))}.
7268 @var{exp} is evaluated in an environment where @code{%outputs} is bound
7269 to a list of output/path pairs, and where @code{%build-inputs} is bound
7270 to a list of string/output-path pairs made from @var{inputs}.
7271 Optionally, @var{env-vars} is a list of string pairs specifying the name
7272 and value of environment variables visible to the builder. The builder
7273 terminates by passing the result of @var{exp} to @code{exit}; thus, when
7274 @var{exp} returns @code{#f}, the build is considered to have failed.
7276 @var{exp} is built using @var{guile-for-build} (a derivation). When
7277 @var{guile-for-build} is omitted or is @code{#f}, the value of the
7278 @code{%guile-for-build} fluid is used instead.
7280 See the @code{derivation} procedure for the meaning of
7281 @var{references-graphs}, @var{allowed-references},
7282 @var{disallowed-references}, @var{local-build?}, and
7283 @var{substitutable?}.
7287 Here's an example of a single-output derivation that creates a directory
7288 containing one file:
7291 (let ((builder '(let ((out (assoc-ref %outputs "out")))
7292 (mkdir out) ; create /gnu/store/@dots{}-goo
7293 (call-with-output-file (string-append out "/test")
7295 (display '(hello guix) p))))))
7296 (build-expression->derivation store "goo" builder))
7298 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
7302 @node The Store Monad
7303 @section The Store Monad
7307 The procedures that operate on the store described in the previous
7308 sections all take an open connection to the build daemon as their first
7309 argument. Although the underlying model is functional, they either have
7310 side effects or depend on the current state of the store.
7312 The former is inconvenient: the connection to the build daemon has to be
7313 carried around in all those functions, making it impossible to compose
7314 functions that do not take that parameter with functions that do. The
7315 latter can be problematic: since store operations have side effects
7316 and/or depend on external state, they have to be properly sequenced.
7318 @cindex monadic values
7319 @cindex monadic functions
7320 This is where the @code{(guix monads)} module comes in. This module
7321 provides a framework for working with @dfn{monads}, and a particularly
7322 useful monad for our uses, the @dfn{store monad}. Monads are a
7323 construct that allows two things: associating ``context'' with values
7324 (in our case, the context is the store), and building sequences of
7325 computations (here computations include accesses to the store). Values
7326 in a monad---values that carry this additional context---are called
7327 @dfn{monadic values}; procedures that return such values are called
7328 @dfn{monadic procedures}.
7330 Consider this ``normal'' procedure:
7333 (define (sh-symlink store)
7334 ;; Return a derivation that symlinks the 'bash' executable.
7335 (let* ((drv (package-derivation store bash))
7336 (out (derivation->output-path drv))
7337 (sh (string-append out "/bin/bash")))
7338 (build-expression->derivation store "sh"
7339 `(symlink ,sh %output))))
7342 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
7343 as a monadic function:
7346 (define (sh-symlink)
7347 ;; Same, but return a monadic value.
7348 (mlet %store-monad ((drv (package->derivation bash)))
7349 (gexp->derivation "sh"
7350 #~(symlink (string-append #$drv "/bin/bash")
7354 There are several things to note in the second version: the @code{store}
7355 parameter is now implicit and is ``threaded'' in the calls to the
7356 @code{package->derivation} and @code{gexp->derivation} monadic
7357 procedures, and the monadic value returned by @code{package->derivation}
7358 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
7360 As it turns out, the call to @code{package->derivation} can even be
7361 omitted since it will take place implicitly, as we will see later
7362 (@pxref{G-Expressions}):
7365 (define (sh-symlink)
7366 (gexp->derivation "sh"
7367 #~(symlink (string-append #$bash "/bin/bash")
7372 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
7373 @c for the funny quote.
7374 Calling the monadic @code{sh-symlink} has no effect. As someone once
7375 said, ``you exit a monad like you exit a building on fire: by running''.
7376 So, to exit the monad and get the desired effect, one must use
7377 @code{run-with-store}:
7380 (run-with-store (open-connection) (sh-symlink))
7381 @result{} /gnu/store/...-sh-symlink
7384 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
7385 new ``meta-commands'' to make it easier to deal with monadic procedures:
7386 @code{run-in-store}, and @code{enter-store-monad}. The former is used
7387 to ``run'' a single monadic value through the store:
7390 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
7391 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7394 The latter enters a recursive REPL, where all the return values are
7395 automatically run through the store:
7398 scheme@@(guile-user)> ,enter-store-monad
7399 store-monad@@(guile-user) [1]> (package->derivation hello)
7400 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7401 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
7402 $3 = "/gnu/store/@dots{}-foo"
7403 store-monad@@(guile-user) [1]> ,q
7404 scheme@@(guile-user)>
7408 Note that non-monadic values cannot be returned in the
7409 @code{store-monad} REPL.
7411 The main syntactic forms to deal with monads in general are provided by
7412 the @code{(guix monads)} module and are described below.
7414 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7415 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7419 @deffn {Scheme Syntax} return @var{val}
7420 Return a monadic value that encapsulates @var{val}.
7423 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7424 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7425 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7426 referred to as ``bind'', but that name denotes an unrelated procedure in
7427 Guile. Thus we use this somewhat cryptic symbol inherited from the
7428 Haskell language.}. There can be one @var{mproc} or several of them, as
7433 (with-monad %state-monad
7435 (lambda (x) (return (+ 1 x)))
7436 (lambda (x) (return (* 2 x)))))
7440 @result{} some-state
7444 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7446 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7448 Bind the variables @var{var} to the monadic values @var{mval} in
7449 @var{body}, which is a sequence of expressions. As with the bind
7450 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7451 value ``contained'' in @var{mval} and making @var{var} refer to that
7452 raw, non-monadic value within the scope of the @var{body}. The form
7453 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7454 @var{val}, as per @code{let}. The binding operations occur in sequence
7455 from left to right. The last expression of @var{body} must be a monadic
7456 expression, and its result will become the result of the @code{mlet} or
7457 @code{mlet*} when run in the @var{monad}.
7459 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7460 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7463 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7464 Bind @var{mexp} and the following monadic expressions in sequence,
7465 returning the result of the last expression. Every expression in the
7466 sequence must be a monadic expression.
7468 This is akin to @code{mlet}, except that the return values of the
7469 monadic expressions are ignored. In that sense, it is analogous to
7470 @code{begin}, but applied to monadic expressions.
7473 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7474 When @var{condition} is true, evaluate the sequence of monadic
7475 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7476 @var{condition} is false, return @code{*unspecified*} in the current
7477 monad. Every expression in the sequence must be a monadic expression.
7480 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7481 When @var{condition} is false, evaluate the sequence of monadic
7482 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7483 @var{condition} is true, return @code{*unspecified*} in the current
7484 monad. Every expression in the sequence must be a monadic expression.
7488 The @code{(guix monads)} module provides the @dfn{state monad}, which
7489 allows an additional value---the state---to be @emph{threaded} through
7490 monadic procedure calls.
7492 @defvr {Scheme Variable} %state-monad
7493 The state monad. Procedures in the state monad can access and change
7494 the state that is threaded.
7496 Consider the example below. The @code{square} procedure returns a value
7497 in the state monad. It returns the square of its argument, but also
7498 increments the current state value:
7502 (mlet %state-monad ((count (current-state)))
7503 (mbegin %state-monad
7504 (set-current-state (+ 1 count))
7507 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7512 When ``run'' through @code{%state-monad}, we obtain that additional state
7513 value, which is the number of @code{square} calls.
7516 @deffn {Monadic Procedure} current-state
7517 Return the current state as a monadic value.
7520 @deffn {Monadic Procedure} set-current-state @var{value}
7521 Set the current state to @var{value} and return the previous state as a
7525 @deffn {Monadic Procedure} state-push @var{value}
7526 Push @var{value} to the current state, which is assumed to be a list,
7527 and return the previous state as a monadic value.
7530 @deffn {Monadic Procedure} state-pop
7531 Pop a value from the current state and return it as a monadic value.
7532 The state is assumed to be a list.
7535 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7536 Run monadic value @var{mval} starting with @var{state} as the initial
7537 state. Return two values: the resulting value, and the resulting state.
7540 The main interface to the store monad, provided by the @code{(guix
7541 store)} module, is as follows.
7543 @defvr {Scheme Variable} %store-monad
7544 The store monad---an alias for @code{%state-monad}.
7546 Values in the store monad encapsulate accesses to the store. When its
7547 effect is needed, a value of the store monad must be ``evaluated'' by
7548 passing it to the @code{run-with-store} procedure (see below).
7551 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7552 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7553 open store connection.
7556 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7557 Return as a monadic value the absolute file name in the store of the file
7558 containing @var{text}, a string. @var{references} is a list of store items that the
7559 resulting text file refers to; it defaults to the empty list.
7562 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7563 Return as a monadic value the absolute file name in the store of the file
7564 containing @var{data}, a bytevector. @var{references} is a list of store
7565 items that the resulting binary file refers to; it defaults to the empty list.
7568 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7569 [#:recursive? #t] [#:select? (const #t)]
7570 Return the name of @var{file} once interned in the store. Use
7571 @var{name} as its store name, or the basename of @var{file} if
7572 @var{name} is omitted.
7574 When @var{recursive?} is true, the contents of @var{file} are added
7575 recursively; if @var{file} designates a flat file and @var{recursive?}
7576 is true, its contents are added, and its permission bits are kept.
7578 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7579 @var{stat})} for each directory entry, where @var{file} is the entry's
7580 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7581 entries for which @var{select?} does not return true.
7583 The example below adds a file to the store, under two different names:
7586 (run-with-store (open-connection)
7587 (mlet %store-monad ((a (interned-file "README"))
7588 (b (interned-file "README" "LEGU-MIN")))
7589 (return (list a b))))
7591 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7596 The @code{(guix packages)} module exports the following package-related
7599 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7600 [#:system (%current-system)] [#:target #f] @
7603 value in the absolute file name of @var{file} within the @var{output}
7604 directory of @var{package}. When @var{file} is omitted, return the name
7605 of the @var{output} directory of @var{package}. When @var{target} is
7606 true, use it as a cross-compilation target triplet.
7608 Note that this procedure does @emph{not} build @var{package}. Thus, the
7609 result might or might not designate an existing file. We recommend not
7610 using this procedure unless you know what you are doing.
7613 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7614 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7615 @var{target} [@var{system}]
7616 Monadic version of @code{package-derivation} and
7617 @code{package-cross-derivation} (@pxref{Defining Packages}).
7622 @section G-Expressions
7624 @cindex G-expression
7625 @cindex build code quoting
7626 So we have ``derivations'', which represent a sequence of build actions
7627 to be performed to produce an item in the store (@pxref{Derivations}).
7628 These build actions are performed when asking the daemon to actually
7629 build the derivations; they are run by the daemon in a container
7630 (@pxref{Invoking guix-daemon}).
7632 @cindex strata of code
7633 It should come as no surprise that we like to write these build actions
7634 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7635 code@footnote{The term @dfn{stratum} in this context was coined by
7636 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7637 Kiselyov, who has written insightful
7638 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7639 on this topic}, refers to this kind of code generation as
7640 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7641 to the daemon, etc.---and the ``build code''---code that actually
7642 performs build actions, such as making directories, invoking
7643 @command{make}, etc.
7645 To describe a derivation and its build actions, one typically needs to
7646 embed build code inside host code. It boils down to manipulating build
7647 code as data, and the homoiconicity of Scheme---code has a direct
7648 representation as data---comes in handy for that. But we need more than
7649 the normal @code{quasiquote} mechanism in Scheme to construct build
7652 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7653 S-expressions adapted to build expressions. G-expressions, or
7654 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7655 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7656 @code{#$}, and @code{#$@@}), which are comparable to
7657 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7658 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7659 GNU Guile Reference Manual}). However, there are major differences:
7663 Gexps are meant to be written to a file and run or manipulated by other
7667 When a high-level object such as a package or derivation is unquoted
7668 inside a gexp, the result is as if its output file name had been
7672 Gexps carry information about the packages or derivations they refer to,
7673 and these dependencies are automatically added as inputs to the build
7674 processes that use them.
7677 @cindex lowering, of high-level objects in gexps
7678 This mechanism is not limited to package and derivation
7679 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7680 derivations or files in the store can be defined,
7681 such that these objects can also be inserted
7682 into gexps. For example, a useful type of high-level objects that can be
7683 inserted in a gexp is ``file-like objects'', which make it easy to
7684 add files to the store and to refer to them in
7685 derivations and such (see @code{local-file} and @code{plain-file}
7688 To illustrate the idea, here is an example of a gexp:
7695 (symlink (string-append #$coreutils "/bin/ls")
7699 This gexp can be passed to @code{gexp->derivation}; we obtain a
7700 derivation that builds a directory containing exactly one symlink to
7701 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7704 (gexp->derivation "the-thing" build-exp)
7707 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7708 substituted to the reference to the @var{coreutils} package in the
7709 actual build code, and @var{coreutils} is automatically made an input to
7710 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7711 output)}) is replaced by a string containing the directory name of the
7712 output of the derivation.
7714 @cindex cross compilation
7715 In a cross-compilation context, it is useful to distinguish between
7716 references to the @emph{native} build of a package---that can run on the
7717 host---versus references to cross builds of a package. To that end, the
7718 @code{#+} plays the same role as @code{#$}, but is a reference to a
7719 native package build:
7722 (gexp->derivation "vi"
7725 (mkdir (string-append #$output "/bin"))
7726 (system* (string-append #+coreutils "/bin/ln")
7728 (string-append #$emacs "/bin/emacs")
7729 (string-append #$output "/bin/vi")))
7730 #:target "aarch64-linux-gnu")
7734 In the example above, the native build of @var{coreutils} is used, so
7735 that @command{ln} can actually run on the host; but then the
7736 cross-compiled build of @var{emacs} is referenced.
7738 @cindex imported modules, for gexps
7739 @findex with-imported-modules
7740 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7741 able to use certain Guile modules from the ``host environment'' in the
7742 gexp, so those modules should be imported in the ``build environment''.
7743 The @code{with-imported-modules} form allows you to express that:
7746 (let ((build (with-imported-modules '((guix build utils))
7748 (use-modules (guix build utils))
7749 (mkdir-p (string-append #$output "/bin"))))))
7750 (gexp->derivation "empty-dir"
7753 (display "success!\n")
7758 In this example, the @code{(guix build utils)} module is automatically
7759 pulled into the isolated build environment of our gexp, such that
7760 @code{(use-modules (guix build utils))} works as expected.
7762 @cindex module closure
7763 @findex source-module-closure
7764 Usually you want the @emph{closure} of the module to be imported---i.e.,
7765 the module itself and all the modules it depends on---rather than just
7766 the module; failing to do that, attempts to use the module will fail
7767 because of missing dependent modules. The @code{source-module-closure}
7768 procedure computes the closure of a module by looking at its source file
7769 headers, which comes in handy in this case:
7772 (use-modules (guix modules)) ;for 'source-module-closure'
7774 (with-imported-modules (source-module-closure
7775 '((guix build utils)
7777 (gexp->derivation "something-with-vms"
7779 (use-modules (guix build utils)
7784 @cindex extensions, for gexps
7785 @findex with-extensions
7786 In the same vein, sometimes you want to import not just pure-Scheme
7787 modules, but also ``extensions'' such as Guile bindings to C libraries
7788 or other ``full-blown'' packages. Say you need the @code{guile-json}
7789 package available on the build side, here's how you would do it:
7792 (use-modules (gnu packages guile)) ;for 'guile-json'
7794 (with-extensions (list guile-json)
7795 (gexp->derivation "something-with-json"
7797 (use-modules (json))
7801 The syntactic form to construct gexps is summarized below.
7803 @deffn {Scheme Syntax} #~@var{exp}
7804 @deffnx {Scheme Syntax} (gexp @var{exp})
7805 Return a G-expression containing @var{exp}. @var{exp} may contain one
7806 or more of the following forms:
7810 @itemx (ungexp @var{obj})
7811 Introduce a reference to @var{obj}. @var{obj} may have one of the
7812 supported types, for example a package or a
7813 derivation, in which case the @code{ungexp} form is replaced by its
7814 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7816 If @var{obj} is a list, it is traversed and references to supported
7817 objects are substituted similarly.
7819 If @var{obj} is another gexp, its contents are inserted and its
7820 dependencies are added to those of the containing gexp.
7822 If @var{obj} is another kind of object, it is inserted as is.
7824 @item #$@var{obj}:@var{output}
7825 @itemx (ungexp @var{obj} @var{output})
7826 This is like the form above, but referring explicitly to the
7827 @var{output} of @var{obj}---this is useful when @var{obj} produces
7828 multiple outputs (@pxref{Packages with Multiple Outputs}).
7831 @itemx #+@var{obj}:output
7832 @itemx (ungexp-native @var{obj})
7833 @itemx (ungexp-native @var{obj} @var{output})
7834 Same as @code{ungexp}, but produces a reference to the @emph{native}
7835 build of @var{obj} when used in a cross compilation context.
7837 @item #$output[:@var{output}]
7838 @itemx (ungexp output [@var{output}])
7839 Insert a reference to derivation output @var{output}, or to the main
7840 output when @var{output} is omitted.
7842 This only makes sense for gexps passed to @code{gexp->derivation}.
7845 @itemx (ungexp-splicing @var{lst})
7846 Like the above, but splices the contents of @var{lst} inside the
7850 @itemx (ungexp-native-splicing @var{lst})
7851 Like the above, but refers to native builds of the objects listed in
7856 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7857 of the @code{gexp?} type (see below).
7860 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7861 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7862 in their execution environment.
7864 Each item in @var{modules} can be the name of a module, such as
7865 @code{(guix build utils)}, or it can be a module name, followed by an
7866 arrow, followed by a file-like object:
7869 `((guix build utils)
7871 ((guix config) => ,(scheme-file "config.scm"
7872 #~(define-module @dots{}))))
7876 In the example above, the first two modules are taken from the search
7877 path, and the last one is created from the given file-like object.
7879 This form has @emph{lexical} scope: it has an effect on the gexps
7880 directly defined in @var{body}@dots{}, but not on those defined, say, in
7881 procedures called from @var{body}@dots{}.
7884 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7885 Mark the gexps defined in @var{body}@dots{} as requiring
7886 @var{extensions} in their build and execution environment.
7887 @var{extensions} is typically a list of package objects such as those
7888 defined in the @code{(gnu packages guile)} module.
7890 Concretely, the packages listed in @var{extensions} are added to the
7891 load path while compiling imported modules in @var{body}@dots{}; they
7892 are also added to the load path of the gexp returned by
7896 @deffn {Scheme Procedure} gexp? @var{obj}
7897 Return @code{#t} if @var{obj} is a G-expression.
7900 G-expressions are meant to be written to disk, either as code building
7901 some derivation, or as plain files in the store. The monadic procedures
7902 below allow you to do that (@pxref{The Store Monad}, for more
7903 information about monads).
7905 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7906 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7907 [#:hash #f] [#:hash-algo #f] @
7908 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7909 [#:module-path @code{%load-path}] @
7910 [#:effective-version "2.2"] @
7911 [#:references-graphs #f] [#:allowed-references #f] @
7912 [#:disallowed-references #f] @
7913 [#:leaked-env-vars #f] @
7914 [#:script-name (string-append @var{name} "-builder")] @
7915 [#:deprecation-warnings #f] @
7916 [#:local-build? #f] [#:substitutable? #t] @
7917 [#:properties '()] [#:guile-for-build #f]
7918 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7919 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7920 stored in a file called @var{script-name}. When @var{target} is true,
7921 it is used as the cross-compilation target triplet for packages referred
7924 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7926 make @var{modules} available in the evaluation context of @var{exp};
7927 @var{modules} is a list of names of Guile modules searched in
7928 @var{module-path} to be copied in the store, compiled, and made available in
7929 the load path during the execution of @var{exp}---e.g., @code{((guix
7930 build utils) (guix build gnu-build-system))}.
7932 @var{effective-version} determines the string to use when adding extensions of
7933 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7935 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7938 When @var{references-graphs} is true, it must be a list of tuples of one of the
7942 (@var{file-name} @var{package})
7943 (@var{file-name} @var{package} @var{output})
7944 (@var{file-name} @var{derivation})
7945 (@var{file-name} @var{derivation} @var{output})
7946 (@var{file-name} @var{store-item})
7949 The right-hand-side of each element of @var{references-graphs} is automatically made
7950 an input of the build process of @var{exp}. In the build environment, each
7951 @var{file-name} contains the reference graph of the corresponding item, in a simple
7954 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7955 In the latter case, the list denotes store items that the result is allowed to
7956 refer to. Any reference to another store item will lead to a build error.
7957 Similarly for @var{disallowed-references}, which can list items that must not be
7958 referenced by the outputs.
7960 @var{deprecation-warnings} determines whether to show deprecation warnings while
7961 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7963 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7966 @cindex file-like objects
7967 The @code{local-file}, @code{plain-file}, @code{computed-file},
7968 @code{program-file}, and @code{scheme-file} procedures below return
7969 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7970 these objects lead to a file in the store. Consider this G-expression:
7973 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7974 #$(local-file "/tmp/my-nscd.conf"))
7977 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7978 to the store. Once expanded, for instance @i{via}
7979 @code{gexp->derivation}, the G-expression refers to that copy under
7980 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7981 does not have any effect on what the G-expression does.
7982 @code{plain-file} can be used similarly; it differs in that the file
7983 content is directly passed as a string.
7985 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7986 [#:recursive? #f] [#:select? (const #t)]
7987 Return an object representing local file @var{file} to add to the store;
7988 this object can be used in a gexp. If @var{file} is a literal string
7989 denoting a relative file name, it is looked up relative to the source
7990 file where it appears; if @var{file} is not a literal string, it is
7991 looked up relative to the current working directory at run time.
7992 @var{file} will be added to the store under @var{name}--by default the
7993 base name of @var{file}.
7995 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7996 designates a flat file and @var{recursive?} is true, its contents are added, and its
7997 permission bits are kept.
7999 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
8000 @var{stat})} for each directory entry, where @var{file} is the entry's
8001 absolute file name and @var{stat} is the result of @code{lstat}; exclude
8002 entries for which @var{select?} does not return true.
8004 This is the declarative counterpart of the @code{interned-file} monadic
8005 procedure (@pxref{The Store Monad, @code{interned-file}}).
8008 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
8009 Return an object representing a text file called @var{name} with the given
8010 @var{content} (a string or a bytevector) to be added to the store.
8012 This is the declarative counterpart of @code{text-file}.
8015 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
8016 [#:options '(#:local-build? #t)]
8017 Return an object representing the store item @var{name}, a file or
8018 directory computed by @var{gexp}. @var{options}
8019 is a list of additional arguments to pass to @code{gexp->derivation}.
8021 This is the declarative counterpart of @code{gexp->derivation}.
8024 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
8025 [#:guile (default-guile)] [#:module-path %load-path] @
8026 [#:system (%current-system)] [#:target #f]
8027 Return an executable script @var{name} that runs @var{exp} using
8028 @var{guile}, with @var{exp}'s imported modules in its search path.
8029 Look up @var{exp}'s modules in @var{module-path}.
8031 The example below builds a script that simply invokes the @command{ls}
8035 (use-modules (guix gexp) (gnu packages base))
8037 (gexp->script "list-files"
8038 #~(execl #$(file-append coreutils "/bin/ls")
8042 When ``running'' it through the store (@pxref{The Store Monad,
8043 @code{run-with-store}}), we obtain a derivation that produces an
8044 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
8047 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
8049 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
8053 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
8054 [#:guile #f] [#:module-path %load-path]
8055 Return an object representing the executable store item @var{name} that
8056 runs @var{gexp}. @var{guile} is the Guile package used to execute that
8057 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
8059 This is the declarative counterpart of @code{gexp->script}.
8062 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
8063 [#:set-load-path? #t] [#:module-path %load-path] @
8065 [#:guile (default-guile)]
8066 Return a derivation that builds a file @var{name} containing @var{exp}.
8067 When @var{splice?} is true, @var{exp} is considered to be a list of
8068 expressions that will be spliced in the resulting file.
8070 When @var{set-load-path?} is true, emit code in the resulting file to
8071 set @code{%load-path} and @code{%load-compiled-path} to honor
8072 @var{exp}'s imported modules. Look up @var{exp}'s modules in
8075 The resulting file holds references to all the dependencies of @var{exp}
8076 or a subset thereof.
8079 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
8080 [#:splice? #f] [#:set-load-path? #t]
8081 Return an object representing the Scheme file @var{name} that contains
8084 This is the declarative counterpart of @code{gexp->file}.
8087 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
8088 Return as a monadic value a derivation that builds a text file
8089 containing all of @var{text}. @var{text} may list, in addition to
8090 strings, objects of any type that can be used in a gexp: packages,
8091 derivations, local file objects, etc. The resulting store file holds
8092 references to all these.
8094 This variant should be preferred over @code{text-file} anytime the file
8095 to create will reference items from the store. This is typically the
8096 case when building a configuration file that embeds store file names,
8100 (define (profile.sh)
8101 ;; Return the name of a shell script in the store that
8102 ;; initializes the 'PATH' environment variable.
8103 (text-file* "profile.sh"
8104 "export PATH=" coreutils "/bin:"
8105 grep "/bin:" sed "/bin\n"))
8108 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
8109 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
8110 preventing them from being garbage-collected during its lifetime.
8113 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
8114 Return an object representing store file @var{name} containing
8115 @var{text}. @var{text} is a sequence of strings and file-like objects,
8119 (mixed-text-file "profile"
8120 "export PATH=" coreutils "/bin:" grep "/bin")
8123 This is the declarative counterpart of @code{text-file*}.
8126 @deffn {Scheme Procedure} file-union @var{name} @var{files}
8127 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
8128 Each item in @var{files} must be a two-element list where the first element is the
8129 file name to use in the new directory, and the second element is a gexp
8130 denoting the target file. Here's an example:
8134 `(("hosts" ,(plain-file "hosts"
8135 "127.0.0.1 localhost"))
8136 ("bashrc" ,(plain-file "bashrc"
8137 "alias ls='ls --color=auto'"))))
8140 This yields an @code{etc} directory containing these two files.
8143 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
8144 Return a directory that is the union of @var{things}, where @var{things} is a list of
8145 file-like objects denoting directories. For example:
8148 (directory-union "guile+emacs" (list guile emacs))
8151 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
8154 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
8155 Return a file-like object that expands to the concatenation of @var{obj}
8156 and @var{suffix}, where @var{obj} is a lowerable object and each
8157 @var{suffix} is a string.
8159 As an example, consider this gexp:
8162 (gexp->script "run-uname"
8163 #~(system* #$(file-append coreutils
8167 The same effect could be achieved with:
8170 (gexp->script "run-uname"
8171 #~(system* (string-append #$coreutils
8175 There is one difference though: in the @code{file-append} case, the
8176 resulting script contains the absolute file name as a string, whereas in
8177 the second case, the resulting script contains a @code{(string-append
8178 @dots{})} expression to construct the file name @emph{at run time}.
8181 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
8182 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
8183 Bind @var{system} to the currently targeted system---e.g.,
8184 @code{"x86_64-linux"}---within @var{body}.
8186 In the second case, additionally bind @var{target} to the current
8187 cross-compilation target---a GNU triplet such as
8188 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
8191 @code{let-system} is useful in the occasional case where the object
8192 spliced into the gexp depends on the target system, as in this example:
8196 #+(let-system system
8197 (cond ((string-prefix? "armhf-" system)
8198 (file-append qemu "/bin/qemu-system-arm"))
8199 ((string-prefix? "x86_64-" system)
8200 (file-append qemu "/bin/qemu-system-x86_64"))
8203 "-net" "user" #$image)
8207 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
8208 This macro is similar to the @code{parameterize} form for
8209 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
8210 Guile Reference Manual}). The key difference is that it takes effect
8211 when the file-like object returned by @var{exp} is lowered to a
8212 derivation or store item.
8214 A typical use of @code{with-parameters} is to force the system in effect
8218 (with-parameters ((%current-system "i686-linux"))
8222 The example above returns an object that corresponds to the i686 build
8223 of Coreutils, regardless of the current value of @code{%current-system}.
8227 Of course, in addition to gexps embedded in ``host'' code, there are
8228 also modules containing build tools. To make it clear that they are
8229 meant to be used in the build stratum, these modules are kept in the
8230 @code{(guix build @dots{})} name space.
8232 @cindex lowering, of high-level objects in gexps
8233 Internally, high-level objects are @dfn{lowered}, using their compiler,
8234 to either derivations or store items. For instance, lowering a package
8235 yields a derivation, and lowering a @code{plain-file} yields a store
8236 item. This is achieved using the @code{lower-object} monadic procedure.
8238 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
8240 Return as a value in @code{%store-monad} the derivation or store item
8241 corresponding to @var{obj} for @var{system}, cross-compiling for
8242 @var{target} if @var{target} is true. @var{obj} must be an object that
8243 has an associated gexp compiler, such as a @code{<package>}.
8246 @node Invoking guix repl
8247 @section Invoking @command{guix repl}
8249 @cindex REPL, read-eval-print loop
8250 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
8251 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
8252 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
8253 command, @command{guix repl} guarantees that all the Guix modules and all its
8254 dependencies are available in the search path. You can use it this way:
8258 scheme@@(guile-user)> ,use (gnu packages base)
8259 scheme@@(guile-user)> coreutils
8260 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
8264 In addition, @command{guix repl} implements a simple machine-readable REPL
8265 protocol for use by @code{(guix inferior)}, a facility to interact with
8266 @dfn{inferiors}, separate processes running a potentially different revision
8269 The available options are as follows:
8272 @item --type=@var{type}
8273 @itemx -t @var{type}
8274 Start a REPL of the given @var{TYPE}, which can be one of the following:
8278 This is default, and it spawns a standard full-featured Guile REPL.
8280 Spawn a REPL that uses the machine-readable protocol. This is the protocol
8281 that the @code{(guix inferior)} module speaks.
8284 @item --listen=@var{endpoint}
8285 By default, @command{guix repl} reads from standard input and writes to
8286 standard output. When this option is passed, it will instead listen for
8287 connections on @var{endpoint}. Here are examples of valid options:
8290 @item --listen=tcp:37146
8291 Accept connections on localhost on port 37146.
8293 @item --listen=unix:/tmp/socket
8294 Accept connections on the Unix-domain socket @file{/tmp/socket}.
8297 @item --load-path=@var{directory}
8298 @itemx -L @var{directory}
8299 Add @var{directory} to the front of the package module search path
8300 (@pxref{Package Modules}).
8302 This allows users to define their own packages and make them visible to
8303 the command-line tool.
8306 Inhibit loading of the @file{~/.guile} file. By default, that
8307 configuration file is loaded when spawning a @code{guile} REPL.
8310 @c *********************************************************************
8314 This section describes Guix command-line utilities. Some of them are
8315 primarily targeted at developers and users who write new package
8316 definitions, while others are more generally useful. They complement
8317 the Scheme programming interface of Guix in a convenient way.
8320 * Invoking guix build:: Building packages from the command line.
8321 * Invoking guix edit:: Editing package definitions.
8322 * Invoking guix download:: Downloading a file and printing its hash.
8323 * Invoking guix hash:: Computing the cryptographic hash of a file.
8324 * Invoking guix import:: Importing package definitions.
8325 * Invoking guix refresh:: Updating package definitions.
8326 * Invoking guix lint:: Finding errors in package definitions.
8327 * Invoking guix size:: Profiling disk usage.
8328 * Invoking guix graph:: Visualizing the graph of packages.
8329 * Invoking guix publish:: Sharing substitutes.
8330 * Invoking guix challenge:: Challenging substitute servers.
8331 * Invoking guix copy:: Copying to and from a remote store.
8332 * Invoking guix container:: Process isolation.
8333 * Invoking guix weather:: Assessing substitute availability.
8334 * Invoking guix processes:: Listing client processes.
8337 @node Invoking guix build
8338 @section Invoking @command{guix build}
8340 @cindex package building
8341 @cindex @command{guix build}
8342 The @command{guix build} command builds packages or derivations and
8343 their dependencies, and prints the resulting store paths. Note that it
8344 does not modify the user's profile---this is the job of the
8345 @command{guix package} command (@pxref{Invoking guix package}). Thus,
8346 it is mainly useful for distribution developers.
8348 The general syntax is:
8351 guix build @var{options} @var{package-or-derivation}@dots{}
8354 As an example, the following command builds the latest versions of Emacs
8355 and of Guile, displays their build logs, and finally displays the
8356 resulting directories:
8359 guix build emacs guile
8362 Similarly, the following command builds all the available packages:
8365 guix build --quiet --keep-going \
8366 `guix package -A | cut -f1,2 --output-delimiter=@@`
8369 @var{package-or-derivation} may be either the name of a package found in
8370 the software distribution such as @code{coreutils} or
8371 @code{coreutils@@8.20}, or a derivation such as
8372 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
8373 package with the corresponding name (and optionally version) is searched
8374 for among the GNU distribution modules (@pxref{Package Modules}).
8376 Alternatively, the @option{--expression} option may be used to specify a
8377 Scheme expression that evaluates to a package; this is useful when
8378 disambiguating among several same-named packages or package variants is
8381 There may be zero or more @var{options}. The available options are
8382 described in the subsections below.
8385 * Common Build Options:: Build options for most commands.
8386 * Package Transformation Options:: Creating variants of packages.
8387 * Additional Build Options:: Options specific to 'guix build'.
8388 * Debugging Build Failures:: Real life packaging experience.
8391 @node Common Build Options
8392 @subsection Common Build Options
8394 A number of options that control the build process are common to
8395 @command{guix build} and other commands that can spawn builds, such as
8396 @command{guix package} or @command{guix archive}. These are the
8401 @item --load-path=@var{directory}
8402 @itemx -L @var{directory}
8403 Add @var{directory} to the front of the package module search path
8404 (@pxref{Package Modules}).
8406 This allows users to define their own packages and make them visible to
8407 the command-line tools.
8411 Keep the build tree of failed builds. Thus, if a build fails, its build
8412 tree is kept under @file{/tmp}, in a directory whose name is shown at
8413 the end of the build log. This is useful when debugging build issues.
8414 @xref{Debugging Build Failures}, for tips and tricks on how to debug
8417 This option implies @option{--no-offload}, and it has no effect when
8418 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
8419 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
8423 Keep going when some of the derivations fail to build; return only once
8424 all the builds have either completed or failed.
8426 The default behavior is to stop as soon as one of the specified
8427 derivations has failed.
8431 Do not build the derivations.
8433 @anchor{fallback-option}
8435 When substituting a pre-built binary fails, fall back to building
8436 packages locally (@pxref{Substitution Failure}).
8438 @item --substitute-urls=@var{urls}
8439 @anchor{client-substitute-urls}
8440 Consider @var{urls} the whitespace-separated list of substitute source
8441 URLs, overriding the default list of URLs of @command{guix-daemon}
8442 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
8444 This means that substitutes may be downloaded from @var{urls}, provided
8445 they are signed by a key authorized by the system administrator
8446 (@pxref{Substitutes}).
8448 When @var{urls} is the empty string, substitutes are effectively
8451 @item --no-substitutes
8452 Do not use substitutes for build products. That is, always build things
8453 locally instead of allowing downloads of pre-built binaries
8454 (@pxref{Substitutes}).
8457 Do not ``graft'' packages. In practice, this means that package updates
8458 available as grafts are not applied. @xref{Security Updates}, for more
8459 information on grafts.
8461 @item --rounds=@var{n}
8462 Build each derivation @var{n} times in a row, and raise an error if
8463 consecutive build results are not bit-for-bit identical.
8465 This is a useful way to detect non-deterministic builds processes.
8466 Non-deterministic build processes are a problem because they make it
8467 practically impossible for users to @emph{verify} whether third-party
8468 binaries are genuine. @xref{Invoking guix challenge}, for more.
8470 Note that, currently, the differing build results are not kept around,
8471 so you will have to manually investigate in case of an error---e.g., by
8472 stashing one of the build results with @code{guix archive --export}
8473 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8477 Do not use offload builds to other machines (@pxref{Daemon Offload
8478 Setup}). That is, always build things locally instead of offloading
8479 builds to remote machines.
8481 @item --max-silent-time=@var{seconds}
8482 When the build or substitution process remains silent for more than
8483 @var{seconds}, terminate it and report a build failure.
8485 By default, the daemon's setting is honored (@pxref{Invoking
8486 guix-daemon, @option{--max-silent-time}}).
8488 @item --timeout=@var{seconds}
8489 Likewise, when the build or substitution process lasts for more than
8490 @var{seconds}, terminate it and report a build failure.
8492 By default, the daemon's setting is honored (@pxref{Invoking
8493 guix-daemon, @option{--timeout}}).
8495 @c Note: This option is actually not part of %standard-build-options but
8496 @c most programs honor it.
8497 @cindex verbosity, of the command-line tools
8498 @cindex build logs, verbosity
8499 @item -v @var{level}
8500 @itemx --verbosity=@var{level}
8501 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8502 output is produced, 1 is for quiet output, and 2 shows all the build log
8503 output on standard error.
8505 @item --cores=@var{n}
8507 Allow the use of up to @var{n} CPU cores for the build. The special
8508 value @code{0} means to use as many CPU cores as available.
8510 @item --max-jobs=@var{n}
8512 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8513 guix-daemon, @option{--max-jobs}}, for details about this option and the
8514 equivalent @command{guix-daemon} option.
8516 @item --debug=@var{level}
8517 Produce debugging output coming from the build daemon. @var{level} must be an
8518 integer between 0 and 5; higher means more verbose output. Setting a level of
8519 4 or more may be helpful when debugging setup issues with the build daemon.
8523 Behind the scenes, @command{guix build} is essentially an interface to
8524 the @code{package-derivation} procedure of the @code{(guix packages)}
8525 module, and to the @code{build-derivations} procedure of the @code{(guix
8526 derivations)} module.
8528 In addition to options explicitly passed on the command line,
8529 @command{guix build} and other @command{guix} commands that support
8530 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
8532 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8533 Users can define this variable to a list of command line options that
8534 will automatically be used by @command{guix build} and other
8535 @command{guix} commands that can perform builds, as in the example
8539 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8542 These options are parsed independently, and the result is appended to
8543 the parsed command-line options.
8547 @node Package Transformation Options
8548 @subsection Package Transformation Options
8550 @cindex package variants
8551 Another set of command-line options supported by @command{guix build}
8552 and also @command{guix package} are @dfn{package transformation
8553 options}. These are options that make it possible to define @dfn{package
8554 variants}---for instance, packages built from different source code.
8555 This is a convenient way to create customized packages on the fly
8556 without having to type in the definitions of package variants
8557 (@pxref{Defining Packages}).
8561 @item --with-source=@var{source}
8562 @itemx --with-source=@var{package}=@var{source}
8563 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8564 Use @var{source} as the source of @var{package}, and @var{version} as
8566 @var{source} must be a file name or a URL, as for @command{guix
8567 download} (@pxref{Invoking guix download}).
8569 When @var{package} is omitted,
8570 it is taken to be the package name specified on the
8571 command line that matches the base of @var{source}---e.g.,
8572 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8573 package is @code{guile}.
8575 Likewise, when @var{version} is omitted, the version string is inferred from
8576 @var{source}; in the previous example, it is @code{2.0.10}.
8578 This option allows users to try out versions of packages other than the
8579 one provided by the distribution. The example below downloads
8580 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8581 the @code{ed} package:
8584 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8587 As a developer, @option{--with-source} makes it easy to test release
8591 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8594 @dots{} or to build from a checkout in a pristine environment:
8597 $ git clone git://git.sv.gnu.org/guix.git
8598 $ guix build guix --with-source=guix@@1.0=./guix
8601 @item --with-input=@var{package}=@var{replacement}
8602 Replace dependency on @var{package} by a dependency on
8603 @var{replacement}. @var{package} must be a package name, and
8604 @var{replacement} must be a package specification such as @code{guile}
8605 or @code{guile@@1.8}.
8607 For instance, the following command builds Guix, but replaces its
8608 dependency on the current stable version of Guile with a dependency on
8609 the legacy version of Guile, @code{guile@@2.0}:
8612 guix build --with-input=guile=guile@@2.0 guix
8615 This is a recursive, deep replacement. So in this example, both
8616 @code{guix} and its dependency @code{guile-json} (which also depends on
8617 @code{guile}) get rebuilt against @code{guile@@2.0}.
8619 This is implemented using the @code{package-input-rewriting} Scheme
8620 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8622 @item --with-graft=@var{package}=@var{replacement}
8623 This is similar to @option{--with-input} but with an important difference:
8624 instead of rebuilding the whole dependency chain, @var{replacement} is
8625 built and then @dfn{grafted} onto the binaries that were initially
8626 referring to @var{package}. @xref{Security Updates}, for more
8627 information on grafts.
8629 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8630 and all its dependencies, replacing references to the version of GnuTLS
8631 they currently refer to:
8634 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8637 This has the advantage of being much faster than rebuilding everything.
8638 But there is a caveat: it works if and only if @var{package} and
8639 @var{replacement} are strictly compatible---for example, if they provide
8640 a library, the application binary interface (ABI) of those libraries
8641 must be compatible. If @var{replacement} is somehow incompatible with
8642 @var{package}, then the resulting package may be unusable. Use with
8645 @item --with-git-url=@var{package}=@var{url}
8646 @cindex Git, using the latest commit
8647 @cindex latest commit, building
8648 Build @var{package} from the latest commit of the @code{master} branch of the
8649 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8652 For example, the following command builds the NumPy Python library against the
8653 latest commit of the master branch of Python itself:
8656 guix build python-numpy \
8657 --with-git-url=python=https://github.com/python/cpython
8660 This option can also be combined with @option{--with-branch} or
8661 @option{--with-commit} (see below).
8663 @cindex continuous integration
8664 Obviously, since it uses the latest commit of the given branch, the result of
8665 such a command varies over time. Nevertheless it is a convenient way to
8666 rebuild entire software stacks against the latest commit of one or more
8667 packages. This is particularly useful in the context of continuous
8670 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8671 consecutive accesses to the same repository. You may want to clean it up once
8672 in a while to save disk space.
8674 @item --with-branch=@var{package}=@var{branch}
8675 Build @var{package} from the latest commit of @var{branch}. If the
8676 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8677 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8678 repository URL is taken from that @code{source}. Otherwise you have to use
8679 @option{--with-git-url} to specify the URL of the Git repository.
8681 For instance, the following command builds @code{guile-sqlite3} from the
8682 latest commit of its @code{master} branch, and then builds @code{guix} (which
8683 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8684 specific @code{guile-sqlite3} build:
8687 guix build --with-branch=guile-sqlite3=master cuirass
8690 @item --with-commit=@var{package}=@var{commit}
8691 This is similar to @option{--with-branch}, except that it builds from
8692 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8693 Git commit SHA1 identifier or a tag.
8696 @node Additional Build Options
8697 @subsection Additional Build Options
8699 The command-line options presented below are specific to @command{guix
8706 Build quietly, without displaying the build log; this is equivalent to
8707 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8708 (or similar) and can always be retrieved using the @option{--log-file} option.
8710 @item --file=@var{file}
8711 @itemx -f @var{file}
8712 Build the package, derivation, or other file-like object that the code within
8713 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8715 As an example, @var{file} might contain a package definition like this
8716 (@pxref{Defining Packages}):
8719 @include package-hello.scm
8722 The @var{file} may also contain a JSON representation of one or more
8723 package definitions. Running @code{guix build -f} on @file{hello.json}
8724 with the following contents would result in building the packages
8725 @code{myhello} and @code{greeter}:
8728 @verbatiminclude package-hello.json
8731 @item --manifest=@var{manifest}
8732 @itemx -m @var{manifest}
8733 Build all packages listed in the given @var{manifest}
8734 (@pxref{profile-manifest, @option{--manifest}}).
8736 @item --expression=@var{expr}
8737 @itemx -e @var{expr}
8738 Build the package or derivation @var{expr} evaluates to.
8740 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8741 guile-1.8)}, which unambiguously designates this specific variant of
8742 version 1.8 of Guile.
8744 Alternatively, @var{expr} may be a G-expression, in which case it is used
8745 as a build program passed to @code{gexp->derivation}
8746 (@pxref{G-Expressions}).
8748 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8749 (@pxref{The Store Monad}). The procedure must return a derivation as a
8750 monadic value, which is then passed through @code{run-with-store}.
8754 Build the source derivations of the packages, rather than the packages
8757 For instance, @code{guix build -S gcc} returns something like
8758 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8761 The returned source tarball is the result of applying any patches and
8762 code snippets specified in the package @code{origin} (@pxref{Defining
8765 Note that @command{guix build -S} compiles the sources only of the
8766 specified packages. They do not include the sources of statically
8767 linked dependencies and by themselves are insufficient for reproducing
8771 Fetch and return the source of @var{package-or-derivation} and all their
8772 dependencies, recursively. This is a handy way to obtain a local copy
8773 of all the source code needed to build @var{packages}, allowing you to
8774 eventually build them even without network access. It is an extension
8775 of the @option{--source} option and can accept one of the following
8776 optional argument values:
8780 This value causes the @option{--sources} option to behave in the same way
8781 as the @option{--source} option.
8784 Build the source derivations of all packages, including any source that
8785 might be listed as @code{inputs}. This is the default value.
8788 $ guix build --sources tzdata
8789 The following derivations will be built:
8790 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8791 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8795 Build the source derivations of all packages, as well of all transitive
8796 inputs to the packages. This can be used e.g.@: to
8797 prefetch package source for later offline building.
8800 $ guix build --sources=transitive tzdata
8801 The following derivations will be built:
8802 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8803 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8804 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8805 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8806 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8807 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8813 @item --system=@var{system}
8814 @itemx -s @var{system}
8815 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8816 the system type of the build host. The @command{guix build} command allows
8817 you to repeat this option several times, in which case it builds for all the
8818 specified systems; other commands ignore extraneous @option{-s} options.
8821 The @option{--system} flag is for @emph{native} compilation and must not
8822 be confused with cross-compilation. See @option{--target} below for
8823 information on cross-compilation.
8826 An example use of this is on Linux-based systems, which can emulate
8827 different personalities. For instance, passing
8828 @option{--system=i686-linux} on an @code{x86_64-linux} system or
8829 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
8830 you to build packages in a complete 32-bit environment.
8833 Building for an @code{armhf-linux} system is unconditionally enabled on
8834 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8835 allow for this functionality, notably the ThunderX.
8838 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8839 is enabled (@pxref{Virtualization Services,
8840 @code{qemu-binfmt-service-type}}), you can build for any system for
8841 which a QEMU @code{binfmt_misc} handler is installed.
8843 Builds for a system other than that of the machine you are using can
8844 also be offloaded to a remote machine of the right architecture.
8845 @xref{Daemon Offload Setup}, for more information on offloading.
8847 @item --target=@var{triplet}
8848 @cindex cross-compilation
8849 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8850 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8851 configuration triplets,, autoconf, Autoconf}).
8853 @anchor{build-check}
8855 @cindex determinism, checking
8856 @cindex reproducibility, checking
8857 Rebuild @var{package-or-derivation}, which are already available in the
8858 store, and raise an error if the build results are not bit-for-bit
8861 This mechanism allows you to check whether previously installed
8862 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8863 of a package is deterministic. @xref{Invoking guix challenge}, for more
8864 background information and tools.
8866 When used in conjunction with @option{--keep-failed}, the differing
8867 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8868 This makes it easy to look for differences between the two results.
8871 @cindex repairing store items
8872 @cindex corruption, recovering from
8873 Attempt to repair the specified store items, if they are corrupt, by
8874 re-downloading or rebuilding them.
8876 This operation is not atomic and thus restricted to @code{root}.
8880 Return the derivation paths, not the output paths, of the given
8883 @item --root=@var{file}
8884 @itemx -r @var{file}
8885 @cindex GC roots, adding
8886 @cindex garbage collector roots, adding
8887 Make @var{file} a symlink to the result, and register it as a garbage
8890 Consequently, the results of this @command{guix build} invocation are
8891 protected from garbage collection until @var{file} is removed. When
8892 that option is omitted, build results are eligible for garbage
8893 collection as soon as the build completes. @xref{Invoking guix gc}, for
8897 @cindex build logs, access
8898 Return the build log file names or URLs for the given
8899 @var{package-or-derivation}, or raise an error if build logs are
8902 This works regardless of how packages or derivations are specified. For
8903 instance, the following invocations are equivalent:
8906 guix build --log-file `guix build -d guile`
8907 guix build --log-file `guix build guile`
8908 guix build --log-file guile
8909 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8912 If a log is unavailable locally, and unless @option{--no-substitutes} is
8913 passed, the command looks for a corresponding log on one of the
8914 substitute servers (as specified with @option{--substitute-urls}).
8916 So for instance, imagine you want to see the build log of GDB on MIPS,
8917 but you are actually on an @code{x86_64} machine:
8920 $ guix build --log-file gdb -s aarch64-linux
8921 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8924 You can freely access a huge library of build logs!
8927 @node Debugging Build Failures
8928 @subsection Debugging Build Failures
8930 @cindex build failures, debugging
8931 When defining a new package (@pxref{Defining Packages}), you will
8932 probably find yourself spending some time debugging and tweaking the
8933 build until it succeeds. To do that, you need to operate the build
8934 commands yourself in an environment as close as possible to the one the
8937 To that end, the first thing to do is to use the @option{--keep-failed}
8938 or @option{-K} option of @command{guix build}, which will keep the
8939 failed build tree in @file{/tmp} or whatever directory you specified as
8940 @env{TMPDIR} (@pxref{Invoking guix build, @option{--keep-failed}}).
8942 From there on, you can @command{cd} to the failed build tree and source
8943 the @file{environment-variables} file, which contains all the
8944 environment variable definitions that were in place when the build
8945 failed. So let's say you're debugging a build failure in package
8946 @code{foo}; a typical session would look like this:
8950 @dots{} @i{build fails}
8951 $ cd /tmp/guix-build-foo.drv-0
8952 $ source ./environment-variables
8956 Now, you can invoke commands as if you were the daemon (almost) and
8957 troubleshoot your build process.
8959 Sometimes it happens that, for example, a package's tests pass when you
8960 run them manually but they fail when the daemon runs them. This can
8961 happen because the daemon runs builds in containers where, unlike in our
8962 environment above, network access is missing, @file{/bin/sh} does not
8963 exist, etc. (@pxref{Build Environment Setup}).
8965 In such cases, you may need to run inspect the build process from within
8966 a container similar to the one the build daemon creates:
8971 $ cd /tmp/guix-build-foo.drv-0
8972 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8973 [env]# source ./environment-variables
8977 Here, @command{guix environment -C} creates a container and spawns a new
8978 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8979 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8980 the container, which you may find handy while debugging. The
8981 @option{--no-grafts} option makes sure we get the exact same
8982 environment, with ungrafted packages (@pxref{Security Updates}, for more
8985 To get closer to a container like that used by the build daemon, we can
8986 remove @file{/bin/sh}:
8992 (Don't worry, this is harmless: this is all happening in the throw-away
8993 container created by @command{guix environment}.)
8995 The @command{strace} command is probably not in the search path, but we
8999 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
9002 In this way, not only you will have reproduced the environment variables
9003 the daemon uses, you will also be running the build process in a container
9004 similar to the one the daemon uses.
9007 @node Invoking guix edit
9008 @section Invoking @command{guix edit}
9010 @cindex @command{guix edit}
9011 @cindex package definition, editing
9012 So many packages, so many source files! The @command{guix edit} command
9013 facilitates the life of users and packagers by pointing their editor at
9014 the source file containing the definition of the specified packages.
9018 guix edit gcc@@4.9 vim
9022 launches the program specified in the @env{VISUAL} or in the
9023 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
9026 If you are using a Guix Git checkout (@pxref{Building from Git}), or
9027 have created your own packages on @env{GUIX_PACKAGE_PATH}
9028 (@pxref{Package Modules}), you will be able to edit the package
9029 recipes. In other cases, you will be able to examine the read-only recipes
9030 for packages currently in the store.
9032 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
9033 @option{--load-path=@var{directory}} (or in short @option{-L
9034 @var{directory}}) allows you to add @var{directory} to the front of the
9035 package module search path and so make your own packages visible.
9037 @node Invoking guix download
9038 @section Invoking @command{guix download}
9040 @cindex @command{guix download}
9041 @cindex downloading package sources
9042 When writing a package definition, developers typically need to download
9043 a source tarball, compute its SHA256 hash, and write that
9044 hash in the package definition (@pxref{Defining Packages}). The
9045 @command{guix download} tool helps with this task: it downloads a file
9046 from the given URI, adds it to the store, and prints both its file name
9047 in the store and its SHA256 hash.
9049 The fact that the downloaded file is added to the store saves bandwidth:
9050 when the developer eventually tries to build the newly defined package
9051 with @command{guix build}, the source tarball will not have to be
9052 downloaded again because it is already in the store. It is also a
9053 convenient way to temporarily stash files, which may be deleted
9054 eventually (@pxref{Invoking guix gc}).
9056 The @command{guix download} command supports the same URIs as used in
9057 package definitions. In particular, it supports @code{mirror://} URIs.
9058 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
9059 Guile bindings for GnuTLS are available in the user's environment; when
9060 they are not available, an error is raised. @xref{Guile Preparations,
9061 how to install the GnuTLS bindings for Guile,, gnutls-guile,
9062 GnuTLS-Guile}, for more information.
9064 @command{guix download} verifies HTTPS server certificates by loading
9065 the certificates of X.509 authorities from the directory pointed to by
9066 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
9067 Certificates}), unless @option{--no-check-certificate} is used.
9069 The following options are available:
9072 @item --hash=@var{algorithm}
9073 @itemx -H @var{algorithm}
9074 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
9075 hash}, for more information.
9077 @item --format=@var{fmt}
9079 Write the hash in the format specified by @var{fmt}. For more
9080 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
9082 @item --no-check-certificate
9083 Do not validate the X.509 certificates of HTTPS servers.
9085 When using this option, you have @emph{absolutely no guarantee} that you
9086 are communicating with the authentic server responsible for the given
9087 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
9089 @item --output=@var{file}
9090 @itemx -o @var{file}
9091 Save the downloaded file to @var{file} instead of adding it to the
9095 @node Invoking guix hash
9096 @section Invoking @command{guix hash}
9098 @cindex @command{guix hash}
9099 The @command{guix hash} command computes the SHA256 hash of a file.
9100 It is primarily a convenience tool for anyone contributing to the
9101 distribution: it computes the cryptographic hash of a file, which can be
9102 used in the definition of a package (@pxref{Defining Packages}).
9104 The general syntax is:
9107 guix hash @var{option} @var{file}
9110 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
9111 hash of data read from standard input. @command{guix hash} has the
9116 @item --hash=@var{algorithm}
9117 @itemx -H @var{algorithm}
9118 Compute a hash using the specified @var{algorithm}, @code{sha256} by
9121 @var{algorithm} must the name of a cryptographic hash algorithm
9122 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
9123 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
9126 @item --format=@var{fmt}
9128 Write the hash in the format specified by @var{fmt}.
9130 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
9131 (@code{hex} and @code{hexadecimal} can be used as well).
9133 If the @option{--format} option is not specified, @command{guix hash}
9134 will output the hash in @code{nix-base32}. This representation is used
9135 in the definitions of packages.
9139 Compute the hash on @var{file} recursively.
9141 In this case, the hash is computed on an archive containing @var{file},
9142 including its children if it is a directory. Some of the metadata of
9143 @var{file} is part of the archive; for instance, when @var{file} is a
9144 regular file, the hash is different depending on whether @var{file} is
9145 executable or not. Metadata such as time stamps has no impact on the
9146 hash (@pxref{Invoking guix archive}).
9147 @c FIXME: Replace xref above with xref to an ``Archive'' section when
9152 When combined with @option{--recursive}, exclude version control system
9153 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
9156 As an example, here is how you would compute the hash of a Git checkout,
9157 which is useful when using the @code{git-fetch} method (@pxref{origin
9161 $ git clone http://example.org/foo.git
9167 @node Invoking guix import
9168 @section Invoking @command{guix import}
9170 @cindex importing packages
9171 @cindex package import
9172 @cindex package conversion
9173 @cindex Invoking @command{guix import}
9174 The @command{guix import} command is useful for people who would like to
9175 add a package to the distribution with as little work as
9176 possible---a legitimate demand. The command knows of a few
9177 repositories from which it can ``import'' package metadata. The result
9178 is a package definition, or a template thereof, in the format we know
9179 (@pxref{Defining Packages}).
9181 The general syntax is:
9184 guix import @var{importer} @var{options}@dots{}
9187 @var{importer} specifies the source from which to import package
9188 metadata, and @var{options} specifies a package identifier and other
9189 options specific to @var{importer}.
9191 Some of the importers rely on the ability to run the @command{gpgv} command.
9192 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
9195 Currently, the available ``importers'' are:
9199 Import metadata for the given GNU package. This provides a template
9200 for the latest version of that GNU package, including the hash of its
9201 source tarball, and its canonical synopsis and description.
9203 Additional information such as the package dependencies and its
9204 license needs to be figured out manually.
9206 For example, the following command returns a package definition for
9210 guix import gnu hello
9213 Specific command-line options are:
9216 @item --key-download=@var{policy}
9217 As for @command{guix refresh}, specify the policy to handle missing
9218 OpenPGP keys when verifying the package signature. @xref{Invoking guix
9219 refresh, @option{--key-download}}.
9224 Import metadata from the @uref{https://pypi.python.org/, Python Package
9225 Index}. Information is taken from the JSON-formatted description
9226 available at @code{pypi.python.org} and usually includes all the relevant
9227 information, including package dependencies. For maximum efficiency, it
9228 is recommended to install the @command{unzip} utility, so that the
9229 importer can unzip Python wheels and gather data from them.
9231 The command below imports metadata for the @code{itsdangerous} Python
9235 guix import pypi itsdangerous
9241 Traverse the dependency graph of the given upstream package recursively
9242 and generate package expressions for all those packages that are not yet
9248 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
9249 is taken from the JSON-formatted description available at
9250 @code{rubygems.org} and includes most relevant information, including
9251 runtime dependencies. There are some caveats, however. The metadata
9252 doesn't distinguish between synopses and descriptions, so the same string
9253 is used for both fields. Additionally, the details of non-Ruby
9254 dependencies required to build native extensions is unavailable and left
9255 as an exercise to the packager.
9257 The command below imports metadata for the @code{rails} Ruby package:
9260 guix import gem rails
9266 Traverse the dependency graph of the given upstream package recursively
9267 and generate package expressions for all those packages that are not yet
9273 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
9274 Information is taken from the JSON-formatted metadata provided through
9275 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
9276 relevant information, such as module dependencies. License information
9277 should be checked closely. If Perl is available in the store, then the
9278 @code{corelist} utility will be used to filter core modules out of the
9279 list of dependencies.
9281 The command command below imports metadata for the Acme::Boolean Perl
9285 guix import cpan Acme::Boolean
9290 @cindex Bioconductor
9291 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
9292 central repository for the @uref{https://r-project.org, GNU@tie{}R
9293 statistical and graphical environment}.
9295 Information is extracted from the @file{DESCRIPTION} file of the package.
9297 The command command below imports metadata for the Cairo R package:
9300 guix import cran Cairo
9303 When @option{--recursive} is added, the importer will traverse the
9304 dependency graph of the given upstream package recursively and generate
9305 package expressions for all those packages that are not yet in Guix.
9307 When @option{--archive=bioconductor} is added, metadata is imported from
9308 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
9309 packages for for the analysis and comprehension of high-throughput
9310 genomic data in bioinformatics.
9312 Information is extracted from the @file{DESCRIPTION} file contained in the
9315 The command below imports metadata for the GenomicRanges R package:
9318 guix import cran --archive=bioconductor GenomicRanges
9321 Finally, you can also import R packages that have not yet been published on
9322 CRAN or Bioconductor as long as they are in a git repository. Use
9323 @option{--archive=git} followed by the URL of the git repository:
9326 guix import cran --archive=git https://github.com/immunogenomics/harmony
9332 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
9333 comprehensive TeX archive network for TeX packages that are part of the
9334 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
9336 Information about the package is obtained through the XML API provided
9337 by CTAN, while the source code is downloaded from the SVN repository of
9338 the Tex Live project. This is done because the CTAN does not keep
9341 The command command below imports metadata for the @code{fontspec}
9345 guix import texlive fontspec
9348 When @option{--archive=@var{directory}} is added, the source code is
9349 downloaded not from the @file{latex} sub-directory of the
9350 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
9351 the specified sibling @var{directory} under the same root.
9353 The command below imports metadata for the @code{ifxetex} package from
9354 CTAN while fetching the sources from the directory
9355 @file{texmf/source/generic}:
9358 guix import texlive --archive=generic ifxetex
9362 @cindex JSON, import
9363 Import package metadata from a local JSON file. Consider the following
9364 example package definition in JSON format:
9370 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
9371 "build-system": "gnu",
9372 "home-page": "https://www.gnu.org/software/hello/",
9373 "synopsis": "Hello, GNU world: An example GNU package",
9374 "description": "GNU Hello prints a greeting.",
9375 "license": "GPL-3.0+",
9376 "native-inputs": ["gettext"]
9380 The field names are the same as for the @code{<package>} record
9381 (@xref{Defining Packages}). References to other packages are provided
9382 as JSON lists of quoted package specification strings such as
9383 @code{guile} or @code{guile@@2.0}.
9385 The importer also supports a more explicit source definition using the
9386 common fields for @code{<origin>} records:
9392 "method": "url-fetch",
9393 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
9395 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
9402 The command below reads metadata from the JSON file @code{hello.json}
9403 and outputs a package expression:
9406 guix import json hello.json
9410 Import metadata from a local copy of the source of the
9411 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
9412 relies on the @command{nix-instantiate} command of
9413 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
9414 typically written in a mixture of Nix-language and Bash code. This
9415 command only imports the high-level package structure that is written in
9416 the Nix language. It normally includes all the basic fields of a
9419 When importing a GNU package, the synopsis and descriptions are replaced
9420 by their canonical upstream variant.
9422 Usually, you will first need to do:
9425 export NIX_REMOTE=daemon
9429 so that @command{nix-instantiate} does not try to open the Nix database.
9431 As an example, the command below imports the package definition of
9432 LibreOffice (more precisely, it imports the definition of the package
9433 bound to the @code{libreoffice} top-level attribute):
9436 guix import nix ~/path/to/nixpkgs libreoffice
9441 Import metadata from the Haskell community's central package archive
9442 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
9443 Cabal files and includes all the relevant information, including package
9446 Specific command-line options are:
9451 Read a Cabal file from standard input.
9452 @item --no-test-dependencies
9454 Do not include dependencies required only by the test suites.
9455 @item --cabal-environment=@var{alist}
9456 @itemx -e @var{alist}
9457 @var{alist} is a Scheme alist defining the environment in which the
9458 Cabal conditionals are evaluated. The accepted keys are: @code{os},
9459 @code{arch}, @code{impl} and a string representing the name of a flag.
9460 The value associated with a flag has to be either the symbol
9461 @code{true} or @code{false}. The value associated with other keys
9462 has to conform to the Cabal file format definition. The default value
9463 associated with the keys @code{os}, @code{arch} and @code{impl} is
9464 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
9467 Traverse the dependency graph of the given upstream package recursively
9468 and generate package expressions for all those packages that are not yet
9472 The command below imports metadata for the latest version of the
9473 HTTP Haskell package without including test dependencies and
9474 specifying the value of the flag @samp{network-uri} as @code{false}:
9477 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
9480 A specific package version may optionally be specified by following the
9481 package name by an at-sign and a version number as in the following example:
9484 guix import hackage mtl@@2.1.3.1
9489 The @code{stackage} importer is a wrapper around the @code{hackage} one.
9490 It takes a package name, looks up the package version included in a
9491 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
9492 release and uses the @code{hackage} importer to retrieve its metadata.
9493 Note that it is up to you to select an LTS release compatible with the
9494 GHC compiler used by Guix.
9496 Specific command-line options are:
9499 @item --no-test-dependencies
9501 Do not include dependencies required only by the test suites.
9502 @item --lts-version=@var{version}
9503 @itemx -l @var{version}
9504 @var{version} is the desired LTS release version. If omitted the latest
9508 Traverse the dependency graph of the given upstream package recursively
9509 and generate package expressions for all those packages that are not yet
9513 The command below imports metadata for the HTTP Haskell package
9514 included in the LTS Stackage release version 7.18:
9517 guix import stackage --lts-version=7.18 HTTP
9522 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9523 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9525 Specific command-line options are:
9528 @item --archive=@var{repo}
9529 @itemx -a @var{repo}
9530 @var{repo} identifies the archive repository from which to retrieve the
9531 information. Currently the supported repositories and their identifiers
9535 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9536 identifier. This is the default.
9538 Packages from @code{elpa.gnu.org} are signed with one of the keys
9539 contained in the GnuPG keyring at
9540 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9541 @code{emacs} package (@pxref{Package Installation, ELPA package
9542 signatures,, emacs, The GNU Emacs Manual}).
9545 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9546 @code{melpa-stable} identifier.
9549 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9555 Traverse the dependency graph of the given upstream package recursively
9556 and generate package expressions for all those packages that are not yet
9562 Import metadata from the crates.io Rust package repository
9563 @uref{https://crates.io, crates.io}, as in this example:
9566 guix import crate blake2-rfc
9569 The crate importer also allows you to specify a version string:
9572 guix import crate constant-time-eq@@0.1.0
9575 Additional options include:
9580 Traverse the dependency graph of the given upstream package recursively
9581 and generate package expressions for all those packages that are not yet
9588 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9589 repository used by the OCaml community.
9592 The structure of the @command{guix import} code is modular. It would be
9593 useful to have more importers for other package formats, and your help
9594 is welcome here (@pxref{Contributing}).
9596 @node Invoking guix refresh
9597 @section Invoking @command{guix refresh}
9599 @cindex @command {guix refresh}
9600 The primary audience of the @command{guix refresh} command is developers
9601 of the GNU software distribution. By default, it reports any packages
9602 provided by the distribution that are outdated compared to the latest
9603 upstream version, like this:
9607 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9608 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9611 Alternatively, one can specify packages to consider, in which case a
9612 warning is emitted for packages that lack an updater:
9615 $ guix refresh coreutils guile guile-ssh
9616 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9617 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9620 @command{guix refresh} browses the upstream repository of each package and determines
9621 the highest version number of the releases therein. The command
9622 knows how to update specific types of packages: GNU packages, ELPA
9623 packages, etc.---see the documentation for @option{--type} below. There
9624 are many packages, though, for which it lacks a method to determine
9625 whether a new upstream release is available. However, the mechanism is
9626 extensible, so feel free to get in touch with us to add a new method!
9631 Consider the packages specified, and all the packages upon which they depend.
9634 $ guix refresh --recursive coreutils
9635 gnu/packages/acl.scm:35:2: warning: no updater for acl
9636 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9637 gnu/packages/xml.scm:68:2: warning: no updater for expat
9638 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9644 Sometimes the upstream name differs from the package name used in Guix,
9645 and @command{guix refresh} needs a little help. Most updaters honor the
9646 @code{upstream-name} property in package definitions, which can be used
9650 (define-public network-manager
9652 (name "network-manager")
9654 (properties '((upstream-name . "NetworkManager")))))
9657 When passed @option{--update}, it modifies distribution source files to
9658 update the version numbers and source tarball hashes of those package
9659 recipes (@pxref{Defining Packages}). This is achieved by downloading
9660 each package's latest source tarball and its associated OpenPGP
9661 signature, authenticating the downloaded tarball against its signature
9662 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
9663 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
9666 key used to sign the tarball is missing from the user's keyring, an
9667 attempt is made to automatically retrieve it from a public key server;
9668 when this is successful, the key is added to the user's keyring; otherwise,
9669 @command{guix refresh} reports an error.
9671 The following options are supported:
9675 @item --expression=@var{expr}
9676 @itemx -e @var{expr}
9677 Consider the package @var{expr} evaluates to.
9679 This is useful to precisely refer to a package, as in this example:
9682 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9685 This command lists the dependents of the ``final'' libc (essentially all
9690 Update distribution source files (package recipes) in place. This is
9691 usually run from a checkout of the Guix source tree (@pxref{Running
9692 Guix Before It Is Installed}):
9695 $ ./pre-inst-env guix refresh -s non-core -u
9698 @xref{Defining Packages}, for more information on package definitions.
9700 @item --select=[@var{subset}]
9701 @itemx -s @var{subset}
9702 Select all the packages in @var{subset}, one of @code{core} or
9705 The @code{core} subset refers to all the packages at the core of the
9706 distribution---i.e., packages that are used to build ``everything
9707 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9708 changing one of these packages in the distribution entails a rebuild of
9709 all the others. Thus, such updates are an inconvenience to users in
9710 terms of build time or bandwidth used to achieve the upgrade.
9712 The @code{non-core} subset refers to the remaining packages. It is
9713 typically useful in cases where an update of the core packages would be
9716 @item --manifest=@var{file}
9717 @itemx -m @var{file}
9718 Select all the packages from the manifest in @var{file}. This is useful to
9719 check if any packages of the user manifest can be updated.
9721 @item --type=@var{updater}
9722 @itemx -t @var{updater}
9723 Select only packages handled by @var{updater} (may be a comma-separated
9724 list of updaters). Currently, @var{updater} may be one of:
9728 the updater for GNU packages;
9730 the updater for GNOME packages;
9732 the updater for KDE packages;
9734 the updater for X.org packages;
9736 the updater for packages hosted on kernel.org;
9738 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9740 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9742 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9744 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9746 the updater for @uref{https://pypi.python.org, PyPI} packages.
9748 the updater for @uref{https://rubygems.org, RubyGems} packages.
9750 the updater for @uref{https://github.com, GitHub} packages.
9752 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9754 the updater for @uref{https://www.stackage.org, Stackage} packages.
9756 the updater for @uref{https://crates.io, Crates} packages.
9758 the updater for @uref{https://launchpad.net, Launchpad} packages.
9761 For instance, the following command only checks for updates of Emacs
9762 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9765 $ guix refresh --type=elpa,cran
9766 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9767 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9772 In addition, @command{guix refresh} can be passed one or more package
9773 names, as in this example:
9776 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9780 The command above specifically updates the @code{emacs} and
9781 @code{idutils} packages. The @option{--select} option would have no
9782 effect in this case.
9784 When considering whether to upgrade a package, it is sometimes
9785 convenient to know which packages would be affected by the upgrade and
9786 should be checked for compatibility. For this the following option may
9787 be used when passing @command{guix refresh} one or more package names:
9791 @item --list-updaters
9793 List available updaters and exit (see @option{--type} above).
9795 For each updater, display the fraction of packages it covers; at the
9796 end, display the fraction of packages covered by all these updaters.
9798 @item --list-dependent
9800 List top-level dependent packages that would need to be rebuilt as a
9801 result of upgrading one or more packages.
9803 @xref{Invoking guix graph, the @code{reverse-package} type of
9804 @command{guix graph}}, for information on how to visualize the list of
9805 dependents of a package.
9809 Be aware that the @option{--list-dependent} option only
9810 @emph{approximates} the rebuilds that would be required as a result of
9811 an upgrade. More rebuilds might be required under some circumstances.
9814 $ guix refresh --list-dependent flex
9815 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9816 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9819 The command above lists a set of packages that could be built to check
9820 for compatibility with an upgraded @code{flex} package.
9824 @item --list-transitive
9825 List all the packages which one or more packages depend upon.
9828 $ guix refresh --list-transitive flex
9829 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9830 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{}
9835 The command above lists a set of packages which, when changed, would cause
9836 @code{flex} to be rebuilt.
9838 The following options can be used to customize GnuPG operation:
9842 @item --gpg=@var{command}
9843 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9844 for in @code{$PATH}.
9846 @item --keyring=@var{file}
9847 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9848 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9849 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9850 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9851 information on a tool to manipulate keybox files).
9853 When this option is omitted, @command{guix refresh} uses
9854 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9855 signing keys. OpenPGP signatures are checked against keys from this keyring;
9856 missing keys are downloaded to this keyring as well (see
9857 @option{--key-download} below).
9859 You can export keys from your default GPG keyring into a keybox file using
9860 commands like this one:
9863 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9866 Likewise, you can fetch keys to a specific keybox file like this:
9869 gpg --no-default-keyring --keyring mykeyring.kbx \
9870 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9873 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9874 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9876 @item --key-download=@var{policy}
9877 Handle missing OpenPGP keys according to @var{policy}, which may be one
9882 Always download missing OpenPGP keys from the key server, and add them
9883 to the user's GnuPG keyring.
9886 Never try to download missing OpenPGP keys. Instead just bail out.
9889 When a package signed with an unknown OpenPGP key is encountered, ask
9890 the user whether to download it or not. This is the default behavior.
9893 @item --key-server=@var{host}
9894 Use @var{host} as the OpenPGP key server when importing a public key.
9896 @item --load-path=@var{directory}
9897 Add @var{directory} to the front of the package module search path
9898 (@pxref{Package Modules}).
9900 This allows users to define their own packages and make them visible to
9901 the command-line tools.
9905 The @code{github} updater uses the
9906 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9907 releases. When used repeatedly e.g.@: when refreshing all packages,
9908 GitHub will eventually refuse to answer any further API requests. By
9909 default 60 API requests per hour are allowed, and a full refresh on all
9910 GitHub packages in Guix requires more than this. Authentication with
9911 GitHub through the use of an API token alleviates these limits. To use
9912 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
9913 token procured from @uref{https://github.com/settings/tokens} or
9917 @node Invoking guix lint
9918 @section Invoking @command{guix lint}
9920 @cindex @command{guix lint}
9921 @cindex package, checking for errors
9922 The @command{guix lint} command is meant to help package developers avoid
9923 common errors and use a consistent style. It runs a number of checks on
9924 a given set of packages in order to find common mistakes in their
9925 definitions. Available @dfn{checkers} include (see
9926 @option{--list-checkers} for a complete list):
9931 Validate certain typographical and stylistic rules about package
9932 descriptions and synopses.
9934 @item inputs-should-be-native
9935 Identify inputs that should most likely be native inputs.
9941 @itemx source-file-name
9942 Probe @code{home-page} and @code{source} URLs and report those that are
9943 invalid. Suggest a @code{mirror://} URL when applicable. If the
9944 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9945 URL. Check that the source file name is meaningful, e.g.@: is not just a
9946 version number or ``git-checkout'', without a declared @code{file-name}
9947 (@pxref{origin Reference}).
9949 @item source-unstable-tarball
9950 Parse the @code{source} URL to determine if a tarball from GitHub is
9951 autogenerated or if it is a release tarball. Unfortunately GitHub's
9952 autogenerated tarballs are sometimes regenerated.
9955 @cindex Software Heritage, source code archive
9956 @cindex archival of source code, Software Heritage
9957 Checks whether the package's source code is archived at
9958 @uref{https://www.softwareheritage.org, Software Heritage}.
9960 When the source code that is not archived comes from a version-control system
9961 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
9962 ``save'' request so that it eventually archives it. This ensures that the
9963 source will remain available in the long term, and that Guix can fall back to
9964 Software Heritage should the source code disappear from its original host.
9965 The status of recent ``save'' requests can be
9966 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
9968 When source code is a tarball obtained with @code{url-fetch}, simply print a
9969 message when it is not archived. As of this writing, Software Heritage does
9970 not allow requests to save arbitrary tarballs; we are working on ways to
9971 ensure that non-VCS source code is also archived.
9974 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
9975 request rate per IP address}. When the limit is reached, @command{guix lint}
9976 prints a message and the @code{archival} checker stops doing anything until
9977 that limit has been reset.
9980 @cindex security vulnerabilities
9981 @cindex CVE, Common Vulnerabilities and Exposures
9982 Report known vulnerabilities found in the Common Vulnerabilities and
9983 Exposures (CVE) databases of the current and past year
9984 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
9987 To view information about a particular vulnerability, visit pages such as:
9991 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9993 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9997 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9998 @code{CVE-2015-7554}.
10000 Package developers can specify in package recipes the
10001 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
10002 name and version of the package when they differ from the name or version
10003 that Guix uses, as in this example:
10009 ;; CPE calls this package "grub2".
10010 (properties '((cpe-name . "grub2")
10011 (cpe-version . "2.3"))))
10014 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
10015 Some entries in the CVE database do not specify which version of a
10016 package they apply to, and would thus ``stick around'' forever. Package
10017 developers who found CVE alerts and verified they can be ignored can
10018 declare them as in this example:
10024 ;; These CVEs no longer apply and can be safely ignored.
10025 (properties `((lint-hidden-cve . ("CVE-2011-0433"
10028 "CVE-2011-5244")))))
10032 Warn about obvious source code formatting issues: trailing white space,
10033 use of tabulations, etc.
10036 The general syntax is:
10039 guix lint @var{options} @var{package}@dots{}
10042 If no package is given on the command line, then all packages are checked.
10043 The @var{options} may be zero or more of the following:
10046 @item --list-checkers
10048 List and describe all the available checkers that will be run on packages
10053 Only enable the checkers specified in a comma-separated list using the
10054 names returned by @option{--list-checkers}.
10056 @item --load-path=@var{directory}
10057 @itemx -L @var{directory}
10058 Add @var{directory} to the front of the package module search path
10059 (@pxref{Package Modules}).
10061 This allows users to define their own packages and make them visible to
10062 the command-line tools.
10066 @node Invoking guix size
10067 @section Invoking @command{guix size}
10070 @cindex package size
10072 @cindex @command{guix size}
10073 The @command{guix size} command helps package developers profile the
10074 disk usage of packages. It is easy to overlook the impact of an
10075 additional dependency added to a package, or the impact of using a
10076 single output for a package that could easily be split (@pxref{Packages
10077 with Multiple Outputs}). Such are the typical issues that
10078 @command{guix size} can highlight.
10080 The command can be passed one or more package specifications
10081 such as @code{gcc@@4.8}
10082 or @code{guile:debug}, or a file name in the store. Consider this
10086 $ guix size coreutils
10087 store item total self
10088 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
10089 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
10090 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
10091 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
10092 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
10093 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
10094 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
10095 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
10100 The store items listed here constitute the @dfn{transitive closure} of
10101 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
10102 would be returned by:
10105 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
10108 Here the output shows three columns next to store items. The first column,
10109 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
10110 the store item---that is, its own size plus the size of all its
10111 dependencies. The next column, labeled ``self'', shows the size of the
10112 item itself. The last column shows the ratio of the size of the item
10113 itself to the space occupied by all the items listed here.
10115 In this example, we see that the closure of Coreutils weighs in at
10116 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
10117 libraries. (That libc and GCC's libraries represent a large fraction of
10118 the closure is not a problem @i{per se} because they are always available
10119 on the system anyway.)
10121 Since the command also accepts store file names, assessing the size of
10122 a build result is straightforward:
10125 guix size $(guix system build config.scm)
10128 When the package(s) passed to @command{guix size} are available in the
10129 store@footnote{More precisely, @command{guix size} looks for the
10130 @emph{ungrafted} variant of the given package(s), as returned by
10131 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
10132 for information on grafts.}, @command{guix size} queries the daemon to determine its
10133 dependencies, and measures its size in the store, similar to @command{du
10134 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
10137 When the given packages are @emph{not} in the store, @command{guix size}
10138 reports information based on the available substitutes
10139 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
10140 store items that are not even on disk, only available remotely.
10142 You can also specify several package names:
10145 $ guix size coreutils grep sed bash
10146 store item total self
10147 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
10148 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
10149 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
10150 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
10156 In this example we see that the combination of the four packages takes
10157 102.3@tie{}MiB in total, which is much less than the sum of each closure
10158 since they have a lot of dependencies in common.
10160 When looking at the profile returned by @command{guix size}, you may
10161 find yourself wondering why a given package shows up in the profile at
10162 all. To understand it, you can use @command{guix graph --path -t
10163 references} to display the shortest path between the two packages
10164 (@pxref{Invoking guix graph}).
10166 The available options are:
10170 @item --substitute-urls=@var{urls}
10171 Use substitute information from @var{urls}.
10172 @xref{client-substitute-urls, the same option for @code{guix build}}.
10174 @item --sort=@var{key}
10175 Sort lines according to @var{key}, one of the following options:
10179 the size of each item (the default);
10181 the total size of the item's closure.
10184 @item --map-file=@var{file}
10185 Write a graphical map of disk usage in PNG format to @var{file}.
10187 For the example above, the map looks like this:
10189 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
10190 produced by @command{guix size}}
10192 This option requires that
10193 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
10194 installed and visible in Guile's module search path. When that is not
10195 the case, @command{guix size} fails as it tries to load it.
10197 @item --system=@var{system}
10198 @itemx -s @var{system}
10199 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
10201 @item --load-path=@var{directory}
10202 @itemx -L @var{directory}
10203 Add @var{directory} to the front of the package module search path
10204 (@pxref{Package Modules}).
10206 This allows users to define their own packages and make them visible to
10207 the command-line tools.
10210 @node Invoking guix graph
10211 @section Invoking @command{guix graph}
10214 @cindex @command{guix graph}
10215 @cindex package dependencies
10216 Packages and their dependencies form a @dfn{graph}, specifically a
10217 directed acyclic graph (DAG). It can quickly become difficult to have a
10218 mental model of the package DAG, so the @command{guix graph} command
10219 provides a visual representation of the DAG. By default,
10220 @command{guix graph} emits a DAG representation in the input format of
10221 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
10222 directly to the @command{dot} command of Graphviz. It can also emit an
10223 HTML page with embedded JavaScript code to display a ``chord diagram''
10224 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
10225 emit Cypher queries to construct a graph in a graph database supporting
10226 the @uref{https://www.opencypher.org/, openCypher} query language. With
10227 @option{--path}, it simply displays the shortest path between two
10228 packages. The general syntax is:
10231 guix graph @var{options} @var{package}@dots{}
10234 For example, the following command generates a PDF file representing the
10235 package DAG for the GNU@tie{}Core Utilities, showing its build-time
10239 guix graph coreutils | dot -Tpdf > dag.pdf
10242 The output looks like this:
10244 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
10246 Nice little graph, no?
10248 You may find it more pleasant to navigate the graph interactively with
10249 @command{xdot} (from the @code{xdot} package):
10252 guix graph coreutils | xdot -
10255 But there is more than one graph! The one above is concise: it is the
10256 graph of package objects, omitting implicit inputs such as GCC, libc,
10257 grep, etc. It is often useful to have such a concise graph, but
10258 sometimes one may want to see more details. @command{guix graph} supports
10259 several types of graphs, allowing you to choose the level of detail:
10263 This is the default type used in the example above. It shows the DAG of
10264 package objects, excluding implicit dependencies. It is concise, but
10265 filters out many details.
10267 @item reverse-package
10268 This shows the @emph{reverse} DAG of packages. For example:
10271 guix graph --type=reverse-package ocaml
10274 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
10275 you are also interested in cases where OCaml is an implicit dependency, see
10276 @code{reverse-bag} below).
10278 Note that for core packages this can yield huge graphs. If all you want
10279 is to know the number of packages that depend on a given package, use
10280 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
10281 @option{--list-dependent}}).
10284 This is the package DAG, @emph{including} implicit inputs.
10286 For instance, the following command:
10289 guix graph --type=bag-emerged coreutils
10292 ...@: yields this bigger graph:
10294 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
10296 At the bottom of the graph, we see all the implicit inputs of
10297 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
10299 Now, note that the dependencies of these implicit inputs---that is, the
10300 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
10301 here, for conciseness.
10304 Similar to @code{bag-emerged}, but this time including all the bootstrap
10307 @item bag-with-origins
10308 Similar to @code{bag}, but also showing origins and their dependencies.
10311 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
10312 it also takes implicit dependencies into account. For example:
10315 guix graph -t reverse-bag dune
10319 ...@: yields the graph of all packages that depend on Dune, directly or
10320 indirectly. Since Dune is an @emph{implicit} dependency of many packages
10321 @i{via} @code{dune-build-system}, this shows a large number of packages,
10322 whereas @code{reverse-package} would show very few if any.
10325 This is the most detailed representation: It shows the DAG of
10326 derivations (@pxref{Derivations}) and plain store items. Compared to
10327 the above representation, many additional nodes are visible, including
10328 build scripts, patches, Guile modules, etc.
10330 For this type of graph, it is also possible to pass a @file{.drv} file
10331 name instead of a package name, as in:
10334 guix graph -t derivation `guix system build -d my-config.scm`
10338 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
10339 For example, the following command shows the graph for the package
10340 module that defines the @code{guile} package:
10343 guix graph -t module guile | xdot -
10347 All the types above correspond to @emph{build-time dependencies}. The
10348 following graph type represents the @emph{run-time dependencies}:
10352 This is the graph of @dfn{references} of a package output, as returned
10353 by @command{guix gc --references} (@pxref{Invoking guix gc}).
10355 If the given package output is not available in the store, @command{guix
10356 graph} attempts to obtain dependency information from substitutes.
10358 Here you can also pass a store file name instead of a package name. For
10359 example, the command below produces the reference graph of your profile
10360 (which can be big!):
10363 guix graph -t references `readlink -f ~/.guix-profile`
10367 This is the graph of the @dfn{referrers} of a store item, as returned by
10368 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
10370 This relies exclusively on local information from your store. For
10371 instance, let us suppose that the current Inkscape is available in 10
10372 profiles on your machine; @command{guix graph -t referrers inkscape}
10373 will show a graph rooted at Inkscape and with those 10 profiles linked
10376 It can help determine what is preventing a store item from being garbage
10381 @cindex shortest path, between packages
10382 Often, the graph of the package you are interested in does not fit on
10383 your screen, and anyway all you want to know is @emph{why} that package
10384 actually depends on some seemingly unrelated package. The
10385 @option{--path} option instructs @command{guix graph} to display the
10386 shortest path between two packages (or derivations, or store items,
10390 $ guix graph --path emacs libunistring
10393 libunistring@@0.9.10
10394 $ guix graph --path -t derivation emacs libunistring
10395 /gnu/store/@dots{}-emacs-26.3.drv
10396 /gnu/store/@dots{}-mailutils-3.9.drv
10397 /gnu/store/@dots{}-libunistring-0.9.10.drv
10398 $ guix graph --path -t references emacs libunistring
10399 /gnu/store/@dots{}-emacs-26.3
10400 /gnu/store/@dots{}-libidn2-2.2.0
10401 /gnu/store/@dots{}-libunistring-0.9.10
10404 The available options are the following:
10407 @item --type=@var{type}
10408 @itemx -t @var{type}
10409 Produce a graph output of @var{type}, where @var{type} must be one of
10410 the values listed above.
10413 List the supported graph types.
10415 @item --backend=@var{backend}
10416 @itemx -b @var{backend}
10417 Produce a graph using the selected @var{backend}.
10419 @item --list-backends
10420 List the supported graph backends.
10422 Currently, the available backends are Graphviz and d3.js.
10425 Display the shortest path between two nodes of the type specified by
10426 @option{--type}. The example below shows the shortest path between
10427 @code{libreoffice} and @code{llvm} according to the references of
10428 @code{libreoffice}:
10431 $ guix graph --path -t references libreoffice llvm
10432 /gnu/store/@dots{}-libreoffice-6.4.2.2
10433 /gnu/store/@dots{}-libepoxy-1.5.4
10434 /gnu/store/@dots{}-mesa-19.3.4
10435 /gnu/store/@dots{}-llvm-9.0.1
10438 @item --expression=@var{expr}
10439 @itemx -e @var{expr}
10440 Consider the package @var{expr} evaluates to.
10442 This is useful to precisely refer to a package, as in this example:
10445 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
10448 @item --system=@var{system}
10449 @itemx -s @var{system}
10450 Display the graph for @var{system}---e.g., @code{i686-linux}.
10452 The package dependency graph is largely architecture-independent, but there
10453 are some architecture-dependent bits that this option allows you to visualize.
10455 @item --load-path=@var{directory}
10456 @itemx -L @var{directory}
10457 Add @var{directory} to the front of the package module search path
10458 (@pxref{Package Modules}).
10460 This allows users to define their own packages and make them visible to
10461 the command-line tools.
10464 On top of that, @command{guix graph} supports all the usual package
10465 transformation options (@pxref{Package Transformation Options}). This
10466 makes it easy to view the effect of a graph-rewriting transformation
10467 such as @option{--with-input}. For example, the command below outputs
10468 the graph of @code{git} once @code{openssl} has been replaced by
10469 @code{libressl} everywhere in the graph:
10472 guix graph git --with-input=openssl=libressl
10475 So many possibilities, so much fun!
10477 @node Invoking guix publish
10478 @section Invoking @command{guix publish}
10480 @cindex @command{guix publish}
10481 The purpose of @command{guix publish} is to enable users to easily share
10482 their store with others, who can then use it as a substitute server
10483 (@pxref{Substitutes}).
10485 When @command{guix publish} runs, it spawns an HTTP server which allows
10486 anyone with network access to obtain substitutes from it. This means
10487 that any machine running Guix can also act as if it were a build farm,
10488 since the HTTP interface is compatible with Cuirass, the software behind
10489 the @code{@value{SUBSTITUTE-SERVER}} build farm.
10491 For security, each substitute is signed, allowing recipients to check
10492 their authenticity and integrity (@pxref{Substitutes}). Because
10493 @command{guix publish} uses the signing key of the system, which is only
10494 readable by the system administrator, it must be started as root; the
10495 @option{--user} option makes it drop root privileges early on.
10497 The signing key pair must be generated before @command{guix publish} is
10498 launched, using @command{guix archive --generate-key} (@pxref{Invoking
10501 The general syntax is:
10504 guix publish @var{options}@dots{}
10507 Running @command{guix publish} without any additional arguments will
10508 spawn an HTTP server on port 8080:
10514 Once a publishing server has been authorized (@pxref{Invoking guix
10515 archive}), the daemon may download substitutes from it:
10518 guix-daemon --substitute-urls=http://example.org:8080
10521 By default, @command{guix publish} compresses archives on the fly as it
10522 serves them. This ``on-the-fly'' mode is convenient in that it requires
10523 no setup and is immediately available. However, when serving lots of
10524 clients, we recommend using the @option{--cache} option, which enables
10525 caching of the archives before they are sent to clients---see below for
10526 details. The @command{guix weather} command provides a handy way to
10527 check what a server provides (@pxref{Invoking guix weather}).
10529 As a bonus, @command{guix publish} also serves as a content-addressed
10530 mirror for source files referenced in @code{origin} records
10531 (@pxref{origin Reference}). For instance, assuming @command{guix
10532 publish} is running on @code{example.org}, the following URL returns the
10533 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
10534 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
10537 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
10540 Obviously, these URLs only work for files that are in the store; in
10541 other cases, they return 404 (``Not Found'').
10543 @cindex build logs, publication
10544 Build logs are available from @code{/log} URLs like:
10547 http://example.org/log/gwspk@dots{}-guile-2.2.3
10551 When @command{guix-daemon} is configured to save compressed build logs,
10552 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
10553 URLs return the compressed log as-is, with an appropriate
10554 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
10555 running @command{guix-daemon} with @option{--log-compression=gzip} since
10556 Web browsers can automatically decompress it, which is not the case with
10559 The following options are available:
10562 @item --port=@var{port}
10563 @itemx -p @var{port}
10564 Listen for HTTP requests on @var{port}.
10566 @item --listen=@var{host}
10567 Listen on the network interface for @var{host}. The default is to
10568 accept connections from any interface.
10570 @item --user=@var{user}
10571 @itemx -u @var{user}
10572 Change privileges to @var{user} as soon as possible---i.e., once the
10573 server socket is open and the signing key has been read.
10575 @item --compression[=@var{method}[:@var{level}]]
10576 @itemx -C [@var{method}[:@var{level}]]
10577 Compress data using the given @var{method} and @var{level}. @var{method} is
10578 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
10581 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
10582 to different compression levels: 1 is the fastest, and 9 is the best
10583 (CPU-intensive). The default is 3.
10585 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
10586 increase in CPU usage; see
10587 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
10590 Unless @option{--cache} is used, compression occurs on the fly and
10591 the compressed streams are not
10592 cached. Thus, to reduce load on the machine that runs @command{guix
10593 publish}, it may be a good idea to choose a low compression level, to
10594 run @command{guix publish} behind a caching proxy, or to use
10595 @option{--cache}. Using @option{--cache} has the advantage that it
10596 allows @command{guix publish} to add @code{Content-Length} HTTP header
10599 This option can be repeated, in which case every substitute gets compressed
10600 using all the selected methods, and all of them are advertised. This is
10601 useful when users may not support all the compression methods: they can select
10602 the one they support.
10604 @item --cache=@var{directory}
10605 @itemx -c @var{directory}
10606 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
10607 and only serve archives that are in cache.
10609 When this option is omitted, archives and meta-data are created
10610 on-the-fly. This can reduce the available bandwidth, especially when
10611 compression is enabled, since this may become CPU-bound. Another
10612 drawback of the default mode is that the length of archives is not known
10613 in advance, so @command{guix publish} does not add a
10614 @code{Content-Length} HTTP header to its responses, which in turn
10615 prevents clients from knowing the amount of data being downloaded.
10617 Conversely, when @option{--cache} is used, the first request for a store
10618 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10619 background process to @dfn{bake} the archive---computing its
10620 @code{.narinfo} and compressing the archive, if needed. Once the
10621 archive is cached in @var{directory}, subsequent requests succeed and
10622 are served directly from the cache, which guarantees that clients get
10623 the best possible bandwidth.
10625 The ``baking'' process is performed by worker threads. By default, one
10626 thread per CPU core is created, but this can be customized. See
10627 @option{--workers} below.
10629 When @option{--ttl} is used, cached entries are automatically deleted
10630 when they have expired.
10632 @item --workers=@var{N}
10633 When @option{--cache} is used, request the allocation of @var{N} worker
10634 threads to ``bake'' archives.
10636 @item --ttl=@var{ttl}
10637 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10638 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10639 days, @code{1m} means 1 month, and so on.
10641 This allows the user's Guix to keep substitute information in cache for
10642 @var{ttl}. However, note that @code{guix publish} does not itself
10643 guarantee that the store items it provides will indeed remain available
10644 for as long as @var{ttl}.
10646 Additionally, when @option{--cache} is used, cached entries that have
10647 not been accessed for @var{ttl} and that no longer have a corresponding
10648 item in the store, may be deleted.
10650 @item --nar-path=@var{path}
10651 Use @var{path} as the prefix for the URLs of ``nar'' files
10652 (@pxref{Invoking guix archive, normalized archives}).
10654 By default, nars are served at a URL such as
10655 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
10656 change the @code{/nar} part to @var{path}.
10658 @item --public-key=@var{file}
10659 @itemx --private-key=@var{file}
10660 Use the specific @var{file}s as the public/private key pair used to sign
10661 the store items being published.
10663 The files must correspond to the same key pair (the private key is used
10664 for signing and the public key is merely advertised in the signature
10665 metadata). They must contain keys in the canonical s-expression format
10666 as produced by @command{guix archive --generate-key} (@pxref{Invoking
10667 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
10668 @file{/etc/guix/signing-key.sec} are used.
10670 @item --repl[=@var{port}]
10671 @itemx -r [@var{port}]
10672 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
10673 Reference Manual}) on @var{port} (37146 by default). This is used
10674 primarily for debugging a running @command{guix publish} server.
10677 Enabling @command{guix publish} on Guix System is a one-liner: just
10678 instantiate a @code{guix-publish-service-type} service in the @code{services} field
10679 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
10680 @code{guix-publish-service-type}}).
10682 If you are instead running Guix on a ``foreign distro'', follow these
10687 If your host distro uses the systemd init system:
10690 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
10691 /etc/systemd/system/
10692 # systemctl start guix-publish && systemctl enable guix-publish
10696 If your host distro uses the Upstart init system:
10699 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
10700 # start guix-publish
10704 Otherwise, proceed similarly with your distro's init system.
10707 @node Invoking guix challenge
10708 @section Invoking @command{guix challenge}
10710 @cindex reproducible builds
10711 @cindex verifiable builds
10712 @cindex @command{guix challenge}
10714 Do the binaries provided by this server really correspond to the source
10715 code it claims to build? Is a package build process deterministic?
10716 These are the questions the @command{guix challenge} command attempts to
10719 The former is obviously an important question: Before using a substitute
10720 server (@pxref{Substitutes}), one had better @emph{verify} that it
10721 provides the right binaries, and thus @emph{challenge} it. The latter
10722 is what enables the former: If package builds are deterministic, then
10723 independent builds of the package should yield the exact same result,
10724 bit for bit; if a server provides a binary different from the one
10725 obtained locally, it may be either corrupt or malicious.
10727 We know that the hash that shows up in @file{/gnu/store} file names is
10728 the hash of all the inputs of the process that built the file or
10729 directory---compilers, libraries, build scripts,
10730 etc. (@pxref{Introduction}). Assuming deterministic build processes,
10731 one store file name should map to exactly one build output.
10732 @command{guix challenge} checks whether there is, indeed, a single
10733 mapping by comparing the build outputs of several independent builds of
10734 any given store item.
10736 The command output looks like this:
10739 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10740 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
10741 updating list of substitutes from 'https://guix.example.org'... 100.0%
10742 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
10743 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10744 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10745 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
10747 /lib/libcrypto.so.1.1
10750 /gnu/store/@dots{}-git-2.5.0 contents differ:
10751 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
10752 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
10753 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
10755 /libexec/git-core/git-fsck
10757 /gnu/store/@dots{}-pius-2.1.1 contents differ:
10758 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10759 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10760 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
10762 /share/man/man1/pius.1.gz
10766 6,406 store items were analyzed:
10767 - 4,749 (74.1%) were identical
10768 - 525 (8.2%) differed
10769 - 1,132 (17.7%) were inconclusive
10773 In this example, @command{guix challenge} first scans the store to
10774 determine the set of locally-built derivations---as opposed to store
10775 items that were downloaded from a substitute server---and then queries
10776 all the substitute servers. It then reports those store items for which
10777 the servers obtained a result different from the local build.
10779 @cindex non-determinism, in package builds
10780 As an example, @code{guix.example.org} always gets a different answer.
10781 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10782 case of Git. This might indicate that the build process of Git is
10783 non-deterministic, meaning that its output varies as a function of
10784 various things that Guix does not fully control, in spite of building
10785 packages in isolated environments (@pxref{Features}). Most common
10786 sources of non-determinism include the addition of timestamps in build
10787 results, the inclusion of random numbers, and directory listings sorted
10788 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
10791 To find out what is wrong with this Git binary, the easiest approach is
10795 guix challenge git \
10796 --diff=diffoscope \
10797 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10800 This automatically invokes @command{diffoscope}, which displays detailed
10801 information about files that differ.
10803 Alternatively, we can do something along these lines (@pxref{Invoking guix
10807 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
10808 | lzip -d | guix archive -x /tmp/git
10809 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
10812 This command shows the difference between the files resulting from the
10813 local build, and the files resulting from the build on
10814 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
10815 diffutils, Comparing and Merging Files}). The @command{diff} command
10816 works great for text files. When binary files differ, a better option
10817 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
10818 visualize differences for all kinds of files.
10820 Once you have done that work, you can tell whether the differences are due
10821 to a non-deterministic build process or to a malicious server. We try
10822 hard to remove sources of non-determinism in packages to make it easier
10823 to verify substitutes, but of course, this is a process that
10824 involves not just Guix, but a large part of the free software community.
10825 In the meantime, @command{guix challenge} is one tool to help address
10828 If you are writing packages for Guix, you are encouraged to check
10829 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
10830 same build result as you did with:
10833 $ guix challenge @var{package}
10837 where @var{package} is a package specification such as
10838 @code{guile@@2.0} or @code{glibc:debug}.
10840 The general syntax is:
10843 guix challenge @var{options} [@var{packages}@dots{}]
10846 When a difference is found between the hash of a locally-built item and
10847 that of a server-provided substitute, or among substitutes provided by
10848 different servers, the command displays it as in the example above and
10849 its exit code is 2 (other non-zero exit codes denote other kinds of
10852 The one option that matters is:
10856 @item --substitute-urls=@var{urls}
10857 Consider @var{urls} the whitespace-separated list of substitute source
10858 URLs to compare to.
10860 @item --diff=@var{mode}
10861 Upon mismatches, show differences according to @var{mode}, one of:
10864 @item @code{simple} (the default)
10865 Show the list of files that differ.
10867 @item @code{diffoscope}
10868 @itemx @var{command}
10869 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
10870 two directories whose contents do not match.
10872 When @var{command} is an absolute file name, run @var{command} instead
10876 Do not show further details about the differences.
10879 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
10880 downloads the store items from the given substitute servers so that it
10885 Show details about matches (identical contents) in addition to
10886 information about mismatches.
10890 @node Invoking guix copy
10891 @section Invoking @command{guix copy}
10893 @cindex copy, of store items, over SSH
10894 @cindex SSH, copy of store items
10895 @cindex sharing store items across machines
10896 @cindex transferring store items across machines
10897 The @command{guix copy} command copies items from the store of one
10898 machine to that of another machine over a secure shell (SSH)
10899 connection@footnote{This command is available only when Guile-SSH was
10900 found. @xref{Requirements}, for details.}. For example, the following
10901 command copies the @code{coreutils} package, the user's profile, and all
10902 their dependencies over to @var{host}, logged in as @var{user}:
10905 guix copy --to=@var{user}@@@var{host} \
10906 coreutils `readlink -f ~/.guix-profile`
10909 If some of the items to be copied are already present on @var{host},
10910 they are not actually sent.
10912 The command below retrieves @code{libreoffice} and @code{gimp} from
10913 @var{host}, assuming they are available there:
10916 guix copy --from=@var{host} libreoffice gimp
10919 The SSH connection is established using the Guile-SSH client, which is
10920 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10921 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10923 The key used to sign items that are sent must be accepted by the remote
10924 machine. Likewise, the key used by the remote machine to sign items you
10925 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10926 own daemon. @xref{Invoking guix archive}, for more information about
10927 store item authentication.
10929 The general syntax is:
10932 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10935 You must always specify one of the following options:
10938 @item --to=@var{spec}
10939 @itemx --from=@var{spec}
10940 Specify the host to send to or receive from. @var{spec} must be an SSH
10941 spec such as @code{example.org}, @code{charlie@@example.org}, or
10942 @code{charlie@@example.org:2222}.
10945 The @var{items} can be either package names, such as @code{gimp}, or
10946 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10948 When specifying the name of a package to send, it is first built if
10949 needed, unless @option{--dry-run} was specified. Common build options
10950 are supported (@pxref{Common Build Options}).
10953 @node Invoking guix container
10954 @section Invoking @command{guix container}
10956 @cindex @command{guix container}
10958 As of version @value{VERSION}, this tool is experimental. The interface
10959 is subject to radical change in the future.
10962 The purpose of @command{guix container} is to manipulate processes
10963 running within an isolated environment, commonly known as a
10964 ``container'', typically created by the @command{guix environment}
10965 (@pxref{Invoking guix environment}) and @command{guix system container}
10966 (@pxref{Invoking guix system}) commands.
10968 The general syntax is:
10971 guix container @var{action} @var{options}@dots{}
10974 @var{action} specifies the operation to perform with a container, and
10975 @var{options} specifies the context-specific arguments for the action.
10977 The following actions are available:
10981 Execute a command within the context of a running container.
10986 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10989 @var{pid} specifies the process ID of the running container.
10990 @var{program} specifies an executable file name within the root file
10991 system of the container. @var{arguments} are the additional options that
10992 will be passed to @var{program}.
10994 The following command launches an interactive login shell inside a
10995 Guix system container, started by @command{guix system container}, and whose
10996 process ID is 9001:
10999 guix container exec 9001 /run/current-system/profile/bin/bash --login
11002 Note that the @var{pid} cannot be the parent process of a container. It
11003 must be PID 1 of the container or one of its child processes.
11007 @node Invoking guix weather
11008 @section Invoking @command{guix weather}
11010 Occasionally you're grumpy because substitutes are lacking and you end
11011 up building packages by yourself (@pxref{Substitutes}). The
11012 @command{guix weather} command reports on substitute availability on the
11013 specified servers so you can have an idea of whether you'll be grumpy
11014 today. It can sometimes be useful info as a user, but it is primarily
11015 useful to people running @command{guix publish} (@pxref{Invoking guix
11018 @cindex statistics, for substitutes
11019 @cindex availability of substitutes
11020 @cindex substitute availability
11021 @cindex weather, substitute availability
11022 Here's a sample run:
11025 $ guix weather --substitute-urls=https://guix.example.org
11026 computing 5,872 package derivations for x86_64-linux...
11027 looking for 6,128 store items on https://guix.example.org..
11028 updating list of substitutes from 'https://guix.example.org'... 100.0%
11029 https://guix.example.org
11030 43.4% substitutes available (2,658 out of 6,128)
11031 7,032.5 MiB of nars (compressed)
11032 19,824.2 MiB on disk (uncompressed)
11033 0.030 seconds per request (182.9 seconds in total)
11034 33.5 requests per second
11036 9.8% (342 out of 3,470) of the missing items are queued
11038 x86_64-linux: 518 (59.7%)
11039 i686-linux: 221 (25.5%)
11040 aarch64-linux: 128 (14.8%)
11041 build rate: 23.41 builds per hour
11042 x86_64-linux: 11.16 builds per hour
11043 i686-linux: 6.03 builds per hour
11044 aarch64-linux: 6.41 builds per hour
11047 @cindex continuous integration, statistics
11048 As you can see, it reports the fraction of all the packages for which
11049 substitutes are available on the server---regardless of whether
11050 substitutes are enabled, and regardless of whether this server's signing
11051 key is authorized. It also reports the size of the compressed archives
11052 (``nars'') provided by the server, the size the corresponding store
11053 items occupy in the store (assuming deduplication is turned off), and
11054 the server's throughput. The second part gives continuous integration
11055 (CI) statistics, if the server supports it. In addition, using the
11056 @option{--coverage} option, @command{guix weather} can list ``important''
11057 package substitutes missing on the server (see below).
11059 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
11060 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
11061 challenge}, it ignores signatures on those substitutes, which is
11062 innocuous since the command only gathers statistics and cannot install
11065 The general syntax is:
11068 guix weather @var{options}@dots{} [@var{packages}@dots{}]
11071 When @var{packages} is omitted, @command{guix weather} checks the availability
11072 of substitutes for @emph{all} the packages, or for those specified with
11073 @option{--manifest}; otherwise it only considers the specified packages. It
11074 is also possible to query specific system types with @option{--system}.
11075 @command{guix weather} exits with a non-zero code when the fraction of
11076 available substitutes is below 100%.
11078 The available options are listed below.
11081 @item --substitute-urls=@var{urls}
11082 @var{urls} is the space-separated list of substitute server URLs to
11083 query. When this option is omitted, the default set of substitute
11084 servers is queried.
11086 @item --system=@var{system}
11087 @itemx -s @var{system}
11088 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
11089 option can be repeated, in which case @command{guix weather} will query
11090 substitutes for several system types.
11092 @item --manifest=@var{file}
11093 Instead of querying substitutes for all the packages, only ask for those
11094 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
11095 with the @code{-m} option of @command{guix package} (@pxref{Invoking
11098 This option can be repeated several times, in which case the manifests
11101 @item --coverage[=@var{count}]
11102 @itemx -c [@var{count}]
11103 Report on substitute coverage for packages: list packages with at least
11104 @var{count} dependents (zero by default) for which substitutes are
11105 unavailable. Dependent packages themselves are not listed: if @var{b} depends
11106 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
11107 @var{b} usually lacks substitutes as well. The result looks like this:
11110 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
11111 computing 8,983 package derivations for x86_64-linux...
11112 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
11113 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
11114 @value{SUBSTITUTE-URL}
11115 64.7% substitutes available (6,047 out of 9,343)
11117 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
11118 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
11119 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
11120 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
11124 What this example shows is that @code{kcoreaddons} and presumably the 58
11125 packages that depend on it have no substitutes at @code{ci.guix.info};
11126 likewise for @code{qgpgme} and the 46 packages that depend on it.
11128 If you are a Guix developer, or if you are taking care of this build farm,
11129 you'll probably want to have a closer look at these packages: they may simply
11132 @item --display-missing
11133 Display the list of store items for which substitutes are missing.
11136 @node Invoking guix processes
11137 @section Invoking @command{guix processes}
11139 The @command{guix processes} command can be useful to developers and system
11140 administrators, especially on multi-user machines and on build farms: it lists
11141 the current sessions (connections to the daemon), as well as information about
11142 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
11143 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
11144 listed.}. Here's an example of the information it returns:
11147 $ sudo guix processes
11150 ClientCommand: guix environment --ad-hoc python
11154 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
11158 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
11159 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
11160 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
11161 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
11162 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
11163 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
11164 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
11167 In this example we see that @command{guix-daemon} has three clients:
11168 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
11169 integration tool; their process identifier (PID) is given by the
11170 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
11171 @command{guix-daemon} sub-process of this particular session.
11173 The @code{LockHeld} fields show which store items are currently locked by this
11174 session, which corresponds to store items being built or substituted (the
11175 @code{LockHeld} field is not displayed when @command{guix processes} is not
11176 running as root). Last, by looking at the @code{ChildProcess} field, we
11177 understand that these three builds are being offloaded (@pxref{Daemon Offload
11180 The output is in Recutils format so we can use the handy @command{recsel}
11181 command to select sessions of interest (@pxref{Selection Expressions,,,
11182 recutils, GNU recutils manual}). As an example, the command shows the command
11183 line and PID of the client that triggered the build of a Perl package:
11186 $ sudo guix processes | \
11187 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
11189 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
11192 @node System Configuration
11193 @chapter System Configuration
11195 @cindex system configuration
11196 Guix System supports a consistent whole-system configuration
11197 mechanism. By that we mean that all aspects of the global system
11198 configuration---such as the available system services, timezone and
11199 locale settings, user accounts---are declared in a single place. Such
11200 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
11202 One of the advantages of putting all the system configuration under the
11203 control of Guix is that it supports transactional system upgrades, and
11204 makes it possible to roll back to a previous system instantiation,
11205 should something go wrong with the new one (@pxref{Features}). Another
11206 advantage is that it makes it easy to replicate the exact same configuration
11207 across different machines, or at different points in time, without
11208 having to resort to additional administration tools layered on top of
11209 the own tools of the system.
11210 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
11212 This section describes this mechanism. First we focus on the system
11213 administrator's viewpoint---explaining how the system is configured and
11214 instantiated. Then we show how this mechanism can be extended, for
11215 instance to support new system services.
11218 * Using the Configuration System:: Customizing your GNU system.
11219 * operating-system Reference:: Detail of operating-system declarations.
11220 * File Systems:: Configuring file system mounts.
11221 * Mapped Devices:: Block device extra processing.
11222 * User Accounts:: Specifying user accounts.
11223 * Keyboard Layout:: How the system interprets key strokes.
11224 * Locales:: Language and cultural convention settings.
11225 * Services:: Specifying system services.
11226 * Setuid Programs:: Programs running with root privileges.
11227 * X.509 Certificates:: Authenticating HTTPS servers.
11228 * Name Service Switch:: Configuring libc's name service switch.
11229 * Initial RAM Disk:: Linux-Libre bootstrapping.
11230 * Bootloader Configuration:: Configuring the boot loader.
11231 * Invoking guix system:: Instantiating a system configuration.
11232 * Invoking guix deploy:: Deploying a system configuration to a remote host.
11233 * Running Guix in a VM:: How to run Guix System in a virtual machine.
11234 * Defining Services:: Adding new service definitions.
11237 @node Using the Configuration System
11238 @section Using the Configuration System
11240 The operating system is configured by providing an
11241 @code{operating-system} declaration in a file that can then be passed to
11242 the @command{guix system} command (@pxref{Invoking guix system}). A
11243 simple setup, with the default system services, the default Linux-Libre
11244 kernel, initial RAM disk, and boot loader looks like this:
11246 @findex operating-system
11248 @include os-config-bare-bones.texi
11251 This example should be self-describing. Some of the fields defined
11252 above, such as @code{host-name} and @code{bootloader}, are mandatory.
11253 Others, such as @code{packages} and @code{services}, can be omitted, in
11254 which case they get a default value.
11256 Below we discuss the effect of some of the most important fields
11257 (@pxref{operating-system Reference}, for details about all the available
11258 fields), and how to @dfn{instantiate} the operating system using
11259 @command{guix system}.
11261 @unnumberedsubsec Bootloader
11263 @cindex legacy boot, on Intel machines
11264 @cindex BIOS boot, on Intel machines
11267 The @code{bootloader} field describes the method that will be used to boot
11268 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
11269 mode, as in the example above. However, more recent machines rely instead on
11270 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
11271 the @code{bootloader} field should contain something along these lines:
11274 (bootloader-configuration
11275 (bootloader grub-efi-bootloader)
11276 (target "/boot/efi"))
11279 @xref{Bootloader Configuration}, for more information on the available
11280 configuration options.
11282 @unnumberedsubsec Globally-Visible Packages
11284 @vindex %base-packages
11285 The @code{packages} field lists packages that will be globally visible
11286 on the system, for all user accounts---i.e., in every user's @env{PATH}
11287 environment variable---in addition to the per-user profiles
11288 (@pxref{Invoking guix package}). The @code{%base-packages} variable
11289 provides all the tools one would expect for basic user and administrator
11290 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
11291 the GNU Zile lightweight text editor, @command{find}, @command{grep},
11292 etc. The example above adds GNU@tie{}Screen to those,
11293 taken from the @code{(gnu packages screen)}
11294 module (@pxref{Package Modules}). The
11295 @code{(list package output)} syntax can be used to add a specific output
11299 (use-modules (gnu packages))
11300 (use-modules (gnu packages dns))
11304 (packages (cons (list bind "utils")
11308 @findex specification->package
11309 Referring to packages by variable name, like @code{bind} above, has
11310 the advantage of being unambiguous; it also allows typos and such to be
11311 diagnosed right away as ``unbound variables''. The downside is that one
11312 needs to know which module defines which package, and to augment the
11313 @code{use-package-modules} line accordingly. To avoid that, one can use
11314 the @code{specification->package} procedure of the @code{(gnu packages)}
11315 module, which returns the best package for a given name or name and
11319 (use-modules (gnu packages))
11323 (packages (append (map specification->package
11324 '("tcpdump" "htop" "gnupg@@2.0"))
11328 @unnumberedsubsec System Services
11331 @vindex %base-services
11332 The @code{services} field lists @dfn{system services} to be made
11333 available when the system starts (@pxref{Services}).
11334 The @code{operating-system} declaration above specifies that, in
11335 addition to the basic services, we want the OpenSSH secure shell
11336 daemon listening on port 2222 (@pxref{Networking Services,
11337 @code{openssh-service-type}}). Under the hood,
11338 @code{openssh-service-type} arranges so that @command{sshd} is started with the
11339 right command-line options, possibly with supporting configuration files
11340 generated as needed (@pxref{Defining Services}).
11342 @cindex customization, of services
11343 @findex modify-services
11344 Occasionally, instead of using the base services as is, you will want to
11345 customize them. To do this, use @code{modify-services} (@pxref{Service
11346 Reference, @code{modify-services}}) to modify the list.
11348 For example, suppose you want to modify @code{guix-daemon} and Mingetty
11349 (the console log-in) in the @code{%base-services} list (@pxref{Base
11350 Services, @code{%base-services}}). To do that, you can write the
11351 following in your operating system declaration:
11354 (define %my-services
11355 ;; My very own list of services.
11356 (modify-services %base-services
11357 (guix-service-type config =>
11358 (guix-configuration
11360 (use-substitutes? #f)
11361 (extra-options '("--gc-keep-derivations"))))
11362 (mingetty-service-type config =>
11363 (mingetty-configuration
11364 (inherit config)))))
11368 (services %my-services))
11371 This changes the configuration---i.e., the service parameters---of the
11372 @code{guix-service-type} instance, and that of all the
11373 @code{mingetty-service-type} instances in the @code{%base-services} list.
11374 Observe how this is accomplished: first, we arrange for the original
11375 configuration to be bound to the identifier @code{config} in the
11376 @var{body}, and then we write the @var{body} so that it evaluates to the
11377 desired configuration. In particular, notice how we use @code{inherit}
11378 to create a new configuration which has the same values as the old
11379 configuration, but with a few modifications.
11381 @cindex encrypted disk
11382 The configuration for a typical ``desktop'' usage, with an encrypted
11383 root partition, the X11 display
11384 server, GNOME and Xfce (users can choose which of these desktop
11385 environments to use at the log-in screen by pressing @kbd{F1}), network
11386 management, power management, and more, would look like this:
11389 @include os-config-desktop.texi
11392 A graphical system with a choice of lightweight window managers
11393 instead of full-blown desktop environments would look like this:
11396 @include os-config-lightweight-desktop.texi
11399 This example refers to the @file{/boot/efi} file system by its UUID,
11400 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
11401 as returned by the @command{blkid} command.
11403 @xref{Desktop Services}, for the exact list of services provided by
11404 @code{%desktop-services}. @xref{X.509 Certificates}, for background
11405 information about the @code{nss-certs} package that is used here.
11407 Again, @code{%desktop-services} is just a list of service objects. If
11408 you want to remove services from there, you can do so using the
11409 procedures for list filtering (@pxref{SRFI-1 Filtering and
11410 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
11411 following expression returns a list that contains all the services in
11412 @code{%desktop-services} minus the Avahi service:
11415 (remove (lambda (service)
11416 (eq? (service-kind service) avahi-service-type))
11420 @unnumberedsubsec Instantiating the System
11422 Assuming the @code{operating-system} declaration
11423 is stored in the @file{my-system-config.scm}
11424 file, the @command{guix system reconfigure my-system-config.scm} command
11425 instantiates that configuration, and makes it the default GRUB boot
11426 entry (@pxref{Invoking guix system}).
11428 The normal way to change the system configuration is by updating this
11429 file and re-running @command{guix system reconfigure}. One should never
11430 have to touch files in @file{/etc} or to run commands that modify the
11431 system state such as @command{useradd} or @command{grub-install}. In
11432 fact, you must avoid that since that would not only void your warranty
11433 but also prevent you from rolling back to previous versions of your
11434 system, should you ever need to.
11436 @cindex roll-back, of the operating system
11437 Speaking of roll-back, each time you run @command{guix system
11438 reconfigure}, a new @dfn{generation} of the system is created---without
11439 modifying or deleting previous generations. Old system generations get
11440 an entry in the bootloader boot menu, allowing you to boot them in case
11441 something went wrong with the latest generation. Reassuring, no? The
11442 @command{guix system list-generations} command lists the system
11443 generations available on disk. It is also possible to roll back the
11444 system via the commands @command{guix system roll-back} and
11445 @command{guix system switch-generation}.
11447 Although the @command{guix system reconfigure} command will not modify
11448 previous generations, you must take care when the current generation is not
11449 the latest (e.g., after invoking @command{guix system roll-back}), since
11450 the operation might overwrite a later generation (@pxref{Invoking guix
11453 @unnumberedsubsec The Programming Interface
11455 At the Scheme level, the bulk of an @code{operating-system} declaration
11456 is instantiated with the following monadic procedure (@pxref{The Store
11459 @deffn {Monadic Procedure} operating-system-derivation os
11460 Return a derivation that builds @var{os}, an @code{operating-system}
11461 object (@pxref{Derivations}).
11463 The output of the derivation is a single directory that refers to all
11464 the packages, configuration files, and other supporting files needed to
11465 instantiate @var{os}.
11468 This procedure is provided by the @code{(gnu system)} module. Along
11469 with @code{(gnu services)} (@pxref{Services}), this module contains the
11470 guts of Guix System. Make sure to visit it!
11473 @node operating-system Reference
11474 @section @code{operating-system} Reference
11476 This section summarizes all the options available in
11477 @code{operating-system} declarations (@pxref{Using the Configuration
11480 @deftp {Data Type} operating-system
11481 This is the data type representing an operating system configuration.
11482 By that, we mean all the global system configuration, not per-user
11483 configuration (@pxref{Using the Configuration System}).
11486 @item @code{kernel} (default: @code{linux-libre})
11487 The package object of the operating system kernel to
11488 use@footnote{Currently only the Linux-libre kernel is fully supported.
11489 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
11490 available when building a virtual machine disk image.}.
11493 @item @code{hurd} (default: @code{#f})
11494 The package object of the hurd to be started by the kernel. When this
11495 field is set, produce a GNU/Hurd operating system. In that case,
11496 @code{kernel} must also be set to the @code{gnumach} package---the
11497 microkernel the Hurd runs on.
11500 This feature is experimental and only supported for disk images.
11503 @item @code{kernel-loadable-modules} (default: '())
11504 A list of objects (usually packages) to collect loadable kernel modules
11505 from--e.g. @code{(list ddcci-driver-linux)}.
11507 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
11508 List of strings or gexps representing additional arguments to pass on
11509 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
11511 @item @code{bootloader}
11512 The system bootloader configuration object. @xref{Bootloader Configuration}.
11515 This is the label (a string) as it appears in the bootloader's menu entry.
11516 The default label includes the kernel name and version.
11518 @item @code{keyboard-layout} (default: @code{#f})
11519 This field specifies the keyboard layout to use in the console. It can be
11520 either @code{#f}, in which case the default keyboard layout is used (usually
11521 US English), or a @code{<keyboard-layout>} record.
11523 This keyboard layout is in effect as soon as the kernel has booted. For
11524 instance, it is the keyboard layout in effect when you type a passphrase if
11525 your root file system is on a @code{luks-device-mapping} mapped device
11526 (@pxref{Mapped Devices}).
11529 This does @emph{not} specify the keyboard layout used by the bootloader, nor
11530 that used by the graphical display server. @xref{Bootloader Configuration},
11531 for information on how to specify the bootloader's keyboard layout. @xref{X
11532 Window}, for information on how to specify the keyboard layout used by the X
11536 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
11538 @cindex initial RAM disk
11539 The list of Linux kernel modules that need to be available in the
11540 initial RAM disk. @xref{Initial RAM Disk}.
11542 @item @code{initrd} (default: @code{base-initrd})
11543 A procedure that returns an initial RAM disk for the Linux
11544 kernel. This field is provided to support low-level customization and
11545 should rarely be needed for casual use. @xref{Initial RAM Disk}.
11547 @item @code{firmware} (default: @code{%base-firmware})
11549 List of firmware packages loadable by the operating system kernel.
11551 The default includes firmware needed for Atheros- and Broadcom-based
11552 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
11553 respectively). @xref{Hardware Considerations}, for more info on
11554 supported hardware.
11556 @item @code{host-name}
11559 @item @code{hosts-file}
11561 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
11562 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
11563 Reference Manual}). The default is a file with entries for
11564 @code{localhost} and @var{host-name}.
11566 @item @code{mapped-devices} (default: @code{'()})
11567 A list of mapped devices. @xref{Mapped Devices}.
11569 @item @code{file-systems}
11570 A list of file systems. @xref{File Systems}.
11572 @item @code{swap-devices} (default: @code{'()})
11573 @cindex swap devices
11574 A list of strings identifying devices or files to be used for ``swap
11575 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
11576 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
11577 It is possible to specify a swap file in a file system on a mapped
11578 device, provided that the necessary device mapping and file system are
11579 also specified. @xref{Mapped Devices} and @ref{File Systems}.
11581 @item @code{users} (default: @code{%base-user-accounts})
11582 @itemx @code{groups} (default: @code{%base-groups})
11583 List of user accounts and groups. @xref{User Accounts}.
11585 If the @code{users} list lacks a user account with UID@tie{}0, a
11586 ``root'' account with UID@tie{}0 is automatically added.
11588 @item @code{skeletons} (default: @code{(default-skeletons)})
11589 A list target file name/file-like object tuples (@pxref{G-Expressions,
11590 file-like objects}). These are the skeleton files that will be added to
11591 the home directory of newly-created user accounts.
11593 For instance, a valid value may look like this:
11596 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
11597 (".guile" ,(plain-file "guile"
11598 "(use-modules (ice-9 readline))
11599 (activate-readline)")))
11602 @item @code{issue} (default: @code{%default-issue})
11603 A string denoting the contents of the @file{/etc/issue} file, which is
11604 displayed when users log in on a text console.
11606 @item @code{packages} (default: @code{%base-packages})
11607 The set of packages installed in the global profile, which is accessible
11608 at @file{/run/current-system/profile}.
11610 The default set includes core utilities and it is good practice to
11611 install non-core utilities in user profiles (@pxref{Invoking guix
11614 @item @code{timezone}
11615 A timezone identifying string---e.g., @code{"Europe/Paris"}.
11617 You can run the @command{tzselect} command to find out which timezone
11618 string corresponds to your region. Choosing an invalid timezone name
11619 causes @command{guix system} to fail.
11621 @item @code{locale} (default: @code{"en_US.utf8"})
11622 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
11623 Library Reference Manual}). @xref{Locales}, for more information.
11625 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
11626 The list of locale definitions to be compiled and that may be used at
11627 run time. @xref{Locales}.
11629 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
11630 The list of GNU@tie{}libc packages whose locale data and tools are used
11631 to build the locale definitions. @xref{Locales}, for compatibility
11632 considerations that justify this option.
11634 @item @code{name-service-switch} (default: @code{%default-nss})
11635 Configuration of the libc name service switch (NSS)---a
11636 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
11639 @item @code{services} (default: @code{%base-services})
11640 A list of service objects denoting system services. @xref{Services}.
11642 @cindex essential services
11643 @item @code{essential-services} (default: ...)
11644 The list of ``essential services''---i.e., things like instances of
11645 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
11646 Reference}), which are derived from the operating system definition itself.
11647 As a user you should @emph{never} need to touch this field.
11649 @item @code{pam-services} (default: @code{(base-pam-services)})
11651 @cindex pluggable authentication modules
11652 Linux @dfn{pluggable authentication module} (PAM) services.
11653 @c FIXME: Add xref to PAM services section.
11655 @item @code{setuid-programs} (default: @code{%setuid-programs})
11656 List of string-valued G-expressions denoting setuid programs.
11657 @xref{Setuid Programs}.
11659 @item @code{sudoers-file} (default: @code{%sudoers-specification})
11660 @cindex sudoers file
11661 The contents of the @file{/etc/sudoers} file as a file-like object
11662 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
11664 This file specifies which users can use the @command{sudo} command, what
11665 they are allowed to do, and what privileges they may gain. The default
11666 is that only @code{root} and members of the @code{wheel} group may use
11671 @deffn {Scheme Syntax} this-operating-system
11672 When used in the @emph{lexical scope} of an operating system field definition,
11673 this identifier resolves to the operating system being defined.
11675 The example below shows how to refer to the operating system being defined in
11676 the definition of the @code{label} field:
11679 (use-modules (gnu) (guix))
11683 (label (package-full-name
11684 (operating-system-kernel this-operating-system))))
11687 It is an error to refer to @code{this-operating-system} outside an operating
11694 @section File Systems
11696 The list of file systems to be mounted is specified in the
11697 @code{file-systems} field of the operating system declaration
11698 (@pxref{Using the Configuration System}). Each file system is declared
11699 using the @code{file-system} form, like this:
11703 (mount-point "/home")
11704 (device "/dev/sda3")
11708 As usual, some of the fields are mandatory---those shown in the example
11709 above---while others can be omitted. These are described below.
11711 @deftp {Data Type} file-system
11712 Objects of this type represent file systems to be mounted. They
11713 contain the following members:
11717 This is a string specifying the type of the file system---e.g.,
11720 @item @code{mount-point}
11721 This designates the place where the file system is to be mounted.
11723 @item @code{device}
11724 This names the ``source'' of the file system. It can be one of three
11725 things: a file system label, a file system UUID, or the name of a
11726 @file{/dev} node. Labels and UUIDs offer a way to refer to file
11727 systems without having to hard-code their actual device
11728 name@footnote{Note that, while it is tempting to use
11729 @file{/dev/disk/by-uuid} and similar device names to achieve the same
11730 result, this is not recommended: These special device nodes are created
11731 by the udev daemon and may be unavailable at the time the device is
11734 @findex file-system-label
11735 File system labels are created using the @code{file-system-label}
11736 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
11737 plain strings. Here's an example of a file system referred to by its
11738 label, as shown by the @command{e2label} command:
11742 (mount-point "/home")
11744 (device (file-system-label "my-home")))
11748 UUIDs are converted from their string representation (as shown by the
11749 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
11750 @code{uuid} form expects 16-byte UUIDs as defined in
11751 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
11752 form of UUID used by the ext2 family of file systems and others, but it
11753 is different from ``UUIDs'' found in FAT file systems, for instance.},
11758 (mount-point "/home")
11760 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
11763 When the source of a file system is a mapped device (@pxref{Mapped
11764 Devices}), its @code{device} field @emph{must} refer to the mapped
11765 device name---e.g., @file{"/dev/mapper/root-partition"}.
11766 This is required so that
11767 the system knows that mounting the file system depends on having the
11768 corresponding device mapping established.
11770 @item @code{flags} (default: @code{'()})
11771 This is a list of symbols denoting mount flags. Recognized flags
11772 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
11773 access to special files), @code{no-suid} (ignore setuid and setgid
11774 bits), @code{no-atime} (do not update file access times),
11775 @code{strict-atime} (update file access time), @code{lazy-time} (only
11776 update time on the in-memory version of the file inode), and
11777 @code{no-exec} (disallow program execution).
11778 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
11779 Manual}, for more information on these flags.
11781 @item @code{options} (default: @code{#f})
11782 This is either @code{#f}, or a string denoting mount options passed to
11783 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
11784 Library Reference Manual}, for details and run @command{man 8 mount} for
11785 options for various file systems. Note that the
11786 @code{file-system-options->alist} and @code{alist->file-system-options}
11787 procedures from @code{(gnu system file-systems)} can be used to convert
11788 file system options given as an association list to the string
11789 representation, and vice-versa.
11791 @item @code{mount?} (default: @code{#t})
11792 This value indicates whether to automatically mount the file system when
11793 the system is brought up. When set to @code{#f}, the file system gets
11794 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
11795 is not automatically mounted.
11797 @item @code{needed-for-boot?} (default: @code{#f})
11798 This Boolean value indicates whether the file system is needed when
11799 booting. If that is true, then the file system is mounted when the
11800 initial RAM disk (initrd) is loaded. This is always the case, for
11801 instance, for the root file system.
11803 @item @code{check?} (default: @code{#t})
11804 This Boolean indicates whether the file system needs to be checked for
11805 errors before being mounted.
11807 @item @code{create-mount-point?} (default: @code{#f})
11808 When true, the mount point is created if it does not exist yet.
11810 @item @code{dependencies} (default: @code{'()})
11811 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
11812 representing file systems that must be mounted or mapped devices that
11813 must be opened before (and unmounted or closed after) this one.
11815 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
11816 a dependency of @file{/sys/fs/cgroup/cpu} and
11817 @file{/sys/fs/cgroup/memory}.
11819 Another example is a file system that depends on a mapped device, for
11820 example for an encrypted partition (@pxref{Mapped Devices}).
11824 The @code{(gnu system file-systems)} exports the following useful
11827 @defvr {Scheme Variable} %base-file-systems
11828 These are essential file systems that are required on normal systems,
11829 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
11830 below). Operating system declarations should always contain at least
11834 @defvr {Scheme Variable} %pseudo-terminal-file-system
11835 This is the file system to be mounted as @file{/dev/pts}. It supports
11836 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
11837 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
11838 Manual}). Pseudo-terminals are used by terminal emulators such as
11842 @defvr {Scheme Variable} %shared-memory-file-system
11843 This file system is mounted as @file{/dev/shm} and is used to support
11844 memory sharing across processes (@pxref{Memory-mapped I/O,
11845 @code{shm_open},, libc, The GNU C Library Reference Manual}).
11848 @defvr {Scheme Variable} %immutable-store
11849 This file system performs a read-only ``bind mount'' of
11850 @file{/gnu/store}, making it read-only for all the users including
11851 @code{root}. This prevents against accidental modification by software
11852 running as @code{root} or by system administrators.
11854 The daemon itself is still able to write to the store: it remounts it
11855 read-write in its own ``name space.''
11858 @defvr {Scheme Variable} %binary-format-file-system
11859 The @code{binfmt_misc} file system, which allows handling of arbitrary
11860 executable file types to be delegated to user space. This requires the
11861 @code{binfmt.ko} kernel module to be loaded.
11864 @defvr {Scheme Variable} %fuse-control-file-system
11865 The @code{fusectl} file system, which allows unprivileged users to mount
11866 and unmount user-space FUSE file systems. This requires the
11867 @code{fuse.ko} kernel module to be loaded.
11870 @node Btrfs file system
11871 @subsection Btrfs file system
11873 The Btrfs has special features, such as subvolumes, that merit being
11874 explained in more details. The following section attempts to cover
11875 basic as well as complex uses of a Btrfs file system with the Guix
11878 In its simplest usage, a Btrfs file system can be described, for
11883 (mount-point "/home")
11885 (device (file-system-label "my-home")))
11888 The example below is more complex, as it makes use of a Btrfs
11889 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
11890 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
11891 dependency on @code{mapped-devices}):
11895 (device (file-system-label "my-btrfs-pool"))
11898 (options "subvol=rootfs")
11899 (dependencies mapped-devices))
11902 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
11903 top level during the early boot, and rely on their configuration to
11904 refer to the correct subvolume path within that top level. The
11905 bootloaders operating in this way typically produce their configuration
11906 on a running system where the Btrfs partitions are already mounted and
11907 where the subvolume information is readily available. As an example,
11908 @command{grub-mkconfig}, the configuration generator command shipped
11909 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
11910 path of a subvolume.
11912 The Guix System produces a bootloader configuration using the operating
11913 system configuration as its sole input; it is therefore necessary to
11914 extract the subvolume name on which @file{/gnu/store} lives (if any)
11915 from that operating system configuration. To better illustrate,
11916 consider a subvolume named 'rootfs' which contains the root file system
11917 data. In such situation, the GRUB bootloader would only see the top
11918 level of the root Btrfs partition, e.g.:
11922 ├── rootfs (subvolume directory)
11923 ├── gnu (normal directory)
11924 ├── store (normal directory)
11928 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
11929 of the kernel, initrd binaries and any other files referred to in the
11930 GRUB configuration that must be found during the early boot.
11932 The next example shows a nested hierarchy of subvolumes and
11937 ├── rootfs (subvolume)
11938 ├── gnu (normal directory)
11939 ├── store (subvolume)
11943 This scenario would work without mounting the 'store' subvolume.
11944 Mounting 'rootfs' is sufficient, since the subvolume name matches its
11945 intended mount point in the file system hierarchy. Alternatively, the
11946 'store' subvolume could be referred to by setting the @code{subvol}
11947 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
11949 Finally, a more contrived example of nested subvolumes:
11953 ├── root-snapshots (subvolume)
11954 ├── root-current (subvolume)
11955 ├── guix-store (subvolume)
11959 Here, the 'guix-store' subvolume doesn't match its intended mount point,
11960 so it is necessary to mount it. The subvolume must be fully specified,
11961 by passing its file name to the @code{subvol} option. To illustrate,
11962 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
11963 a file system declaration such as:
11967 (device (file-system-label "btrfs-pool-1"))
11968 (mount-point "/gnu/store")
11970 (options "subvol=root-snapshots/root-current/guix-store,\
11971 compress-force=zstd,space_cache=v2"))
11974 @node Mapped Devices
11975 @section Mapped Devices
11977 @cindex device mapping
11978 @cindex mapped devices
11979 The Linux kernel has a notion of @dfn{device mapping}: a block device,
11980 such as a hard disk partition, can be @dfn{mapped} into another device,
11981 usually in @code{/dev/mapper/},
11982 with additional processing over the data that flows through
11983 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
11984 concept of a ``mapped device'' and that of a file system: both boil down
11985 to @emph{translating} input/output operations made on a file to
11986 operations on its backing store. Thus, the Hurd implements mapped
11987 devices, like file systems, using the generic @dfn{translator} mechanism
11988 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
11989 typical example is encryption device mapping: all writes to the mapped
11990 device are encrypted, and all reads are deciphered, transparently.
11991 Guix extends this notion by considering any device or set of devices that
11992 are @dfn{transformed} in some way to create a new device; for instance,
11993 RAID devices are obtained by @dfn{assembling} several other devices, such
11994 as hard disks or partitions, into a new one that behaves as one partition.
11995 Other examples, not yet implemented, are LVM logical volumes.
11997 Mapped devices are declared using the @code{mapped-device} form,
11998 defined as follows; for examples, see below.
12000 @deftp {Data Type} mapped-device
12001 Objects of this type represent device mappings that will be made when
12002 the system boots up.
12006 This is either a string specifying the name of the block device to be mapped,
12007 such as @code{"/dev/sda3"}, or a list of such strings when several devices
12008 need to be assembled for creating a new one.
12011 This string specifies the name of the resulting mapped device. For
12012 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
12013 specifying @code{"my-partition"} leads to the creation of
12014 the @code{"/dev/mapper/my-partition"} device.
12015 For RAID devices of type @code{raid-device-mapping}, the full device name
12016 such as @code{"/dev/md0"} needs to be given.
12019 This must be a @code{mapped-device-kind} object, which specifies how
12020 @var{source} is mapped to @var{target}.
12024 @defvr {Scheme Variable} luks-device-mapping
12025 This defines LUKS block device encryption using the @command{cryptsetup}
12026 command from the package with the same name. It relies on the
12027 @code{dm-crypt} Linux kernel module.
12030 @defvr {Scheme Variable} raid-device-mapping
12031 This defines a RAID device, which is assembled using the @code{mdadm}
12032 command from the package with the same name. It requires a Linux kernel
12033 module for the appropriate RAID level to be loaded, such as @code{raid456}
12034 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
12037 @cindex disk encryption
12039 The following example specifies a mapping from @file{/dev/sda3} to
12040 @file{/dev/mapper/home} using LUKS---the
12041 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
12042 standard mechanism for disk encryption.
12043 The @file{/dev/mapper/home}
12044 device can then be used as the @code{device} of a @code{file-system}
12045 declaration (@pxref{File Systems}).
12049 (source "/dev/sda3")
12051 (type luks-device-mapping))
12054 Alternatively, to become independent of device numbering, one may obtain
12055 the LUKS UUID (@dfn{unique identifier}) of the source device by a
12059 cryptsetup luksUUID /dev/sda3
12062 and use it as follows:
12066 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
12068 (type luks-device-mapping))
12071 @cindex swap encryption
12072 It is also desirable to encrypt swap space, since swap space may contain
12073 sensitive data. One way to accomplish that is to use a swap file in a
12074 file system on a device mapped via LUKS encryption. In this way, the
12075 swap file is encrypted because the entire device is encrypted.
12076 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
12078 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
12079 may be declared as follows:
12083 (source (list "/dev/sda1" "/dev/sdb1"))
12084 (target "/dev/md0")
12085 (type raid-device-mapping))
12088 The @file{/dev/md0} device can then be used as the @code{device} of a
12089 @code{file-system} declaration (@pxref{File Systems}).
12090 Note that the RAID level need not be given; it is chosen during the
12091 initial creation and formatting of the RAID device and is determined
12092 automatically later.
12095 @node User Accounts
12096 @section User Accounts
12100 @cindex user accounts
12101 User accounts and groups are entirely managed through the
12102 @code{operating-system} declaration. They are specified with the
12103 @code{user-account} and @code{user-group} forms:
12109 (supplementary-groups '("wheel" ;allow use of sudo, etc.
12110 "audio" ;sound card
12111 "video" ;video devices such as webcams
12112 "cdrom")) ;the good ol' CD-ROM
12113 (comment "Bob's sister")
12114 (home-directory "/home/alice"))
12117 When booting or upon completion of @command{guix system reconfigure},
12118 the system ensures that only the user accounts and groups specified in
12119 the @code{operating-system} declaration exist, and with the specified
12120 properties. Thus, account or group creations or modifications made by
12121 directly invoking commands such as @command{useradd} are lost upon
12122 reconfiguration or reboot. This ensures that the system remains exactly
12125 @deftp {Data Type} user-account
12126 Objects of this type represent user accounts. The following members may
12131 The name of the user account.
12135 This is the name (a string) or identifier (a number) of the user group
12136 this account belongs to.
12138 @item @code{supplementary-groups} (default: @code{'()})
12139 Optionally, this can be defined as a list of group names that this
12140 account belongs to.
12142 @item @code{uid} (default: @code{#f})
12143 This is the user ID for this account (a number), or @code{#f}. In the
12144 latter case, a number is automatically chosen by the system when the
12145 account is created.
12147 @item @code{comment} (default: @code{""})
12148 A comment about the account, such as the account owner's full name.
12150 @item @code{home-directory}
12151 This is the name of the home directory for the account.
12153 @item @code{create-home-directory?} (default: @code{#t})
12154 Indicates whether the home directory of this account should be created
12155 if it does not exist yet.
12157 @item @code{shell} (default: Bash)
12158 This is a G-expression denoting the file name of a program to be used as
12159 the shell (@pxref{G-Expressions}).
12161 @item @code{system?} (default: @code{#f})
12162 This Boolean value indicates whether the account is a ``system''
12163 account. System accounts are sometimes treated specially; for instance,
12164 graphical login managers do not list them.
12166 @anchor{user-account-password}
12167 @cindex password, for user accounts
12168 @item @code{password} (default: @code{#f})
12169 You would normally leave this field to @code{#f}, initialize user
12170 passwords as @code{root} with the @command{passwd} command, and then let
12171 users change it with @command{passwd}. Passwords set with
12172 @command{passwd} are of course preserved across reboot and
12175 If you @emph{do} want to set an initial password for an account, then
12176 this field must contain the encrypted password, as a string. You can use the
12177 @code{crypt} procedure for this purpose:
12184 ;; Specify a SHA-512-hashed initial password.
12185 (password (crypt "InitialPassword!" "$6$abc")))
12189 The hash of this initial password will be available in a file in
12190 @file{/gnu/store}, readable by all the users, so this method must be used with
12194 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
12195 more information on password encryption, and @ref{Encryption,,, guile, GNU
12196 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
12202 User group declarations are even simpler:
12205 (user-group (name "students"))
12208 @deftp {Data Type} user-group
12209 This type is for, well, user groups. There are just a few fields:
12213 The name of the group.
12215 @item @code{id} (default: @code{#f})
12216 The group identifier (a number). If @code{#f}, a new number is
12217 automatically allocated when the group is created.
12219 @item @code{system?} (default: @code{#f})
12220 This Boolean value indicates whether the group is a ``system'' group.
12221 System groups have low numerical IDs.
12223 @item @code{password} (default: @code{#f})
12224 What, user groups can have a password? Well, apparently yes. Unless
12225 @code{#f}, this field specifies the password of the group.
12230 For convenience, a variable lists all the basic user groups one may
12233 @defvr {Scheme Variable} %base-groups
12234 This is the list of basic user groups that users and/or packages expect
12235 to be present on the system. This includes groups such as ``root'',
12236 ``wheel'', and ``users'', as well as groups used to control access to
12237 specific devices such as ``audio'', ``disk'', and ``cdrom''.
12240 @defvr {Scheme Variable} %base-user-accounts
12241 This is the list of basic system accounts that programs may expect to
12242 find on a GNU/Linux system, such as the ``nobody'' account.
12244 Note that the ``root'' account is not included here. It is a
12245 special-case and is automatically added whether or not it is specified.
12248 @node Keyboard Layout
12249 @section Keyboard Layout
12251 @cindex keyboard layout
12253 To specify what each key of your keyboard does, you need to tell the operating
12254 system what @dfn{keyboard layout} you want to use. The default, when nothing
12255 is specified, is the US English QWERTY layout for 105-key PC keyboards.
12256 However, German speakers will usually prefer the German QWERTZ layout, French
12257 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
12258 or bépo, and they might even want to further customize the effect of some of
12259 the keys. This section explains how to get that done.
12261 @cindex keyboard layout, definition
12262 There are three components that will want to know about your keyboard layout:
12266 The @emph{bootloader} may want to know what keyboard layout you want to use
12267 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
12268 you want, for instance, to make sure that you can type the passphrase of your
12269 encrypted root partition using the right layout.
12272 The @emph{operating system kernel}, Linux, will need that so that the console
12273 is properly configured (@pxref{operating-system Reference,
12274 @code{keyboard-layout}}).
12277 The @emph{graphical display server}, usually Xorg, also has its own idea of
12278 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
12281 Guix allows you to configure all three separately but, fortunately, it allows
12282 you to share the same keyboard layout for all three components.
12284 @cindex XKB, keyboard layouts
12285 Keyboard layouts are represented by records created by the
12286 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
12287 the X Keyboard extension (XKB), each layout has four attributes: a name (often
12288 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
12289 optional variant name, an optional keyboard model name, and a possibly empty
12290 list of additional options. In most cases the layout name is all you care
12291 about. Here are a few example:
12294 ;; The German QWERTZ layout. Here we assume a standard
12295 ;; "pc105" keyboard model.
12296 (keyboard-layout "de")
12298 ;; The bépo variant of the French layout.
12299 (keyboard-layout "fr" "bepo")
12301 ;; The Catalan layout.
12302 (keyboard-layout "es" "cat")
12304 ;; Arabic layout with "Alt-Shift" to switch to US layout.
12305 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
12307 ;; The Latin American Spanish layout. In addition, the
12308 ;; "Caps Lock" key is used as an additional "Ctrl" key,
12309 ;; and the "Menu" key is used as a "Compose" key to enter
12310 ;; accented letters.
12311 (keyboard-layout "latam"
12312 #:options '("ctrl:nocaps" "compose:menu"))
12314 ;; The Russian layout for a ThinkPad keyboard.
12315 (keyboard-layout "ru" #:model "thinkpad")
12317 ;; The "US international" layout, which is the US layout plus
12318 ;; dead keys to enter accented characters. This is for an
12319 ;; Apple MacBook keyboard.
12320 (keyboard-layout "us" "intl" #:model "macbook78")
12323 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
12324 for a complete list of supported layouts, variants, and models.
12326 @cindex keyboard layout, configuration
12327 Let's say you want your system to use the Turkish keyboard layout throughout
12328 your system---bootloader, console, and Xorg. Here's what your system
12329 configuration would look like:
12331 @findex set-xorg-configuration
12333 ;; Using the Turkish layout for the bootloader, the console,
12338 (keyboard-layout (keyboard-layout "tr")) ;for the console
12339 (bootloader (bootloader-configuration
12340 (bootloader grub-efi-bootloader)
12341 (target "/boot/efi")
12342 (keyboard-layout keyboard-layout))) ;for GRUB
12343 (services (cons (set-xorg-configuration
12344 (xorg-configuration ;for Xorg
12345 (keyboard-layout keyboard-layout)))
12346 %desktop-services)))
12349 In the example above, for GRUB and for Xorg, we just refer to the
12350 @code{keyboard-layout} field defined above, but we could just as well refer to
12351 a different layout. The @code{set-xorg-configuration} procedure communicates
12352 the desired Xorg configuration to the graphical log-in manager, by default
12355 We've discussed how to specify the @emph{default} keyboard layout of your
12356 system when it starts, but you can also adjust it at run time:
12360 If you're using GNOME, its settings panel has a ``Region & Language'' entry
12361 where you can select one or more keyboard layouts.
12364 Under Xorg, the @command{setxkbmap} command (from the same-named package)
12365 allows you to change the current layout. For example, this is how you would
12366 change the layout to US Dvorak:
12369 setxkbmap us dvorak
12373 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
12374 console. However, note that @code{loadkeys} does @emph{not} use the XKB
12375 keyboard layout categorization described above. The command below loads the
12376 French bépo layout:
12387 A @dfn{locale} defines cultural conventions for a particular language
12388 and region of the world (@pxref{Locales,,, libc, The GNU C Library
12389 Reference Manual}). Each locale has a name that typically has the form
12390 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
12391 @code{fr_LU.utf8} designates the locale for the French language, with
12392 cultural conventions from Luxembourg, and using the UTF-8 encoding.
12394 @cindex locale definition
12395 Usually, you will want to specify the default locale for the machine
12396 using the @code{locale} field of the @code{operating-system} declaration
12397 (@pxref{operating-system Reference, @code{locale}}).
12399 The selected locale is automatically added to the @dfn{locale
12400 definitions} known to the system if needed, with its codeset inferred
12401 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
12402 @code{UTF-8} codeset. Additional locale definitions can be specified in
12403 the @code{locale-definitions} slot of @code{operating-system}---this is
12404 useful, for instance, if the codeset could not be inferred from the
12405 locale name. The default set of locale definitions includes some widely
12406 used locales, but not all the available locales, in order to save space.
12408 For instance, to add the North Frisian locale for Germany, the value of
12412 (cons (locale-definition
12413 (name "fy_DE.utf8") (source "fy_DE"))
12414 %default-locale-definitions)
12417 Likewise, to save space, one might want @code{locale-definitions} to
12418 list only the locales that are actually used, as in:
12421 (list (locale-definition
12422 (name "ja_JP.eucjp") (source "ja_JP")
12423 (charset "EUC-JP")))
12427 The compiled locale definitions are available at
12428 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
12429 version, which is the default location where the GNU@tie{}libc provided
12430 by Guix looks for locale data. This can be overridden using the
12431 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
12432 @env{LOCPATH} and locale packages}).
12434 The @code{locale-definition} form is provided by the @code{(gnu system
12435 locale)} module. Details are given below.
12437 @deftp {Data Type} locale-definition
12438 This is the data type of a locale definition.
12443 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
12444 Reference Manual}, for more information on locale names.
12446 @item @code{source}
12447 The name of the source for that locale. This is typically the
12448 @code{@var{language}_@var{territory}} part of the locale name.
12450 @item @code{charset} (default: @code{"UTF-8"})
12451 The ``character set'' or ``code set'' for that locale,
12452 @uref{https://www.iana.org/assignments/character-sets, as defined by
12458 @defvr {Scheme Variable} %default-locale-definitions
12459 A list of commonly used UTF-8 locales, used as the default
12460 value of the @code{locale-definitions} field of @code{operating-system}
12463 @cindex locale name
12464 @cindex normalized codeset in locale names
12465 These locale definitions use the @dfn{normalized codeset} for the part
12466 that follows the dot in the name (@pxref{Using gettextized software,
12467 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
12468 instance it has @code{uk_UA.utf8} but @emph{not}, say,
12469 @code{uk_UA.UTF-8}.
12472 @subsection Locale Data Compatibility Considerations
12474 @cindex incompatibility, of locale data
12475 @code{operating-system} declarations provide a @code{locale-libcs} field
12476 to specify the GNU@tie{}libc packages that are used to compile locale
12477 declarations (@pxref{operating-system Reference}). ``Why would I
12478 care?'', you may ask. Well, it turns out that the binary format of
12479 locale data is occasionally incompatible from one libc version to
12482 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
12483 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
12484 For instance, a program linked against libc version 2.21 is unable to
12485 read locale data produced with libc 2.22; worse, that program
12486 @emph{aborts} instead of simply ignoring the incompatible locale
12487 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
12488 the incompatible locale data, which is already an improvement.}.
12489 Similarly, a program linked against libc 2.22 can read most, but not
12490 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
12491 data is incompatible); thus calls to @code{setlocale} may fail, but
12492 programs will not abort.
12494 The ``problem'' with Guix is that users have a lot of freedom: They can
12495 choose whether and when to upgrade software in their profiles, and might
12496 be using a libc version different from the one the system administrator
12497 used to build the system-wide locale data.
12499 Fortunately, unprivileged users can also install their own locale data
12500 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
12501 @env{GUIX_LOCPATH} and locale packages}).
12503 Still, it is best if the system-wide locale data at
12504 @file{/run/current-system/locale} is built for all the libc versions
12505 actually in use on the system, so that all the programs can access
12506 it---this is especially crucial on a multi-user system. To do that, the
12507 administrator can specify several libc packages in the
12508 @code{locale-libcs} field of @code{operating-system}:
12511 (use-package-modules base)
12515 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
12518 This example would lead to a system containing locale definitions for
12519 both libc 2.21 and the current version of libc in
12520 @file{/run/current-system/locale}.
12526 @cindex system services
12527 An important part of preparing an @code{operating-system} declaration is
12528 listing @dfn{system services} and their configuration (@pxref{Using the
12529 Configuration System}). System services are typically daemons launched
12530 when the system boots, or other actions needed at that time---e.g.,
12531 configuring network access.
12533 Guix has a broad definition of ``service'' (@pxref{Service
12534 Composition}), but many services are managed by the GNU@tie{}Shepherd
12535 (@pxref{Shepherd Services}). On a running system, the @command{herd}
12536 command allows you to list the available services, show their status,
12537 start and stop them, or do other specific operations (@pxref{Jump
12538 Start,,, shepherd, The GNU Shepherd Manual}). For example:
12544 The above command, run as @code{root}, lists the currently defined
12545 services. The @command{herd doc} command shows a synopsis of the given
12546 service and its associated actions:
12550 Run libc's name service cache daemon (nscd).
12552 # herd doc nscd action invalidate
12553 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
12556 The @command{start}, @command{stop}, and @command{restart} sub-commands
12557 have the effect you would expect. For instance, the commands below stop
12558 the nscd service and restart the Xorg display server:
12562 Service nscd has been stopped.
12563 # herd restart xorg-server
12564 Service xorg-server has been stopped.
12565 Service xorg-server has been started.
12568 The following sections document the available services, starting with
12569 the core services, that may be used in an @code{operating-system}
12573 * Base Services:: Essential system services.
12574 * Scheduled Job Execution:: The mcron service.
12575 * Log Rotation:: The rottlog service.
12576 * Networking Services:: Network setup, SSH daemon, etc.
12577 * X Window:: Graphical display.
12578 * Printing Services:: Local and remote printer support.
12579 * Desktop Services:: D-Bus and desktop services.
12580 * Sound Services:: ALSA and Pulseaudio services.
12581 * Database Services:: SQL databases, key-value stores, etc.
12582 * Mail Services:: IMAP, POP3, SMTP, and all that.
12583 * Messaging Services:: Messaging services.
12584 * Telephony Services:: Telephony services.
12585 * Monitoring Services:: Monitoring services.
12586 * Kerberos Services:: Kerberos services.
12587 * LDAP Services:: LDAP services.
12588 * Web Services:: Web servers.
12589 * Certificate Services:: TLS certificates via Let's Encrypt.
12590 * DNS Services:: DNS daemons.
12591 * VPN Services:: VPN daemons.
12592 * Network File System:: NFS related services.
12593 * Continuous Integration:: The Cuirass service.
12594 * Power Management Services:: Extending battery life.
12595 * Audio Services:: The MPD.
12596 * Virtualization Services:: Virtualization services.
12597 * Version Control Services:: Providing remote access to Git repositories.
12598 * Game Services:: Game servers.
12599 * PAM Mount Service:: Service to mount volumes when logging in.
12600 * Guix Services:: Services relating specifically to Guix.
12601 * Linux Services:: Services tied to the Linux kernel.
12602 * Miscellaneous Services:: Other services.
12605 @node Base Services
12606 @subsection Base Services
12608 The @code{(gnu services base)} module provides definitions for the basic
12609 services that one expects from the system. The services exported by
12610 this module are listed below.
12612 @defvr {Scheme Variable} %base-services
12613 This variable contains a list of basic services (@pxref{Service Types
12614 and Services}, for more information on service objects) one would
12615 expect from the system: a login service (mingetty) on each tty, syslogd,
12616 the libc name service cache daemon (nscd), the udev device manager, and
12619 This is the default value of the @code{services} field of
12620 @code{operating-system} declarations. Usually, when customizing a
12621 system, you will want to append services to @code{%base-services}, like
12625 (append (list (service avahi-service-type)
12626 (service openssh-service-type))
12631 @defvr {Scheme Variable} special-files-service-type
12632 This is the service that sets up ``special files'' such as
12633 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
12635 The value associated with @code{special-files-service-type} services
12636 must be a list of tuples where the first element is the ``special file''
12637 and the second element is its target. By default it is:
12639 @cindex @file{/bin/sh}
12640 @cindex @file{sh}, in @file{/bin}
12642 `(("/bin/sh" ,(file-append bash "/bin/sh")))
12645 @cindex @file{/usr/bin/env}
12646 @cindex @file{env}, in @file{/usr/bin}
12647 If you want to add, say, @code{/usr/bin/env} to your system, you can
12651 `(("/bin/sh" ,(file-append bash "/bin/sh"))
12652 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
12655 Since this is part of @code{%base-services}, you can use
12656 @code{modify-services} to customize the set of special files
12657 (@pxref{Service Reference, @code{modify-services}}). But the simple way
12658 to add a special file is @i{via} the @code{extra-special-file} procedure
12662 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
12663 Use @var{target} as the ``special file'' @var{file}.
12665 For example, adding the following lines to the @code{services} field of
12666 your operating system declaration leads to a @file{/usr/bin/env}
12670 (extra-special-file "/usr/bin/env"
12671 (file-append coreutils "/bin/env"))
12675 @deffn {Scheme Procedure} host-name-service @var{name}
12676 Return a service that sets the host name to @var{name}.
12679 @defvr {Scheme Variable} console-font-service-type
12680 Install the given fonts on the specified ttys (fonts are per
12681 virtual console on the kernel Linux). The value of this service is a list of
12682 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
12683 package or any valid argument to @command{setfont}, as in this example:
12686 `(("tty1" . "LatGrkCyr-8x16")
12687 ("tty2" . ,(file-append
12689 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
12690 ("tty3" . ,(file-append
12692 "/share/consolefonts/ter-132n"))) ; for HDPI
12696 @deffn {Scheme Procedure} login-service @var{config}
12697 Return a service to run login according to @var{config}, a
12698 @code{<login-configuration>} object, which specifies the message of the day,
12699 among other things.
12702 @deftp {Data Type} login-configuration
12703 This is the data type representing the configuration of login.
12708 @cindex message of the day
12709 A file-like object containing the ``message of the day''.
12711 @item @code{allow-empty-passwords?} (default: @code{#t})
12712 Allow empty passwords by default so that first-time users can log in when
12713 the 'root' account has just been created.
12718 @deffn {Scheme Procedure} mingetty-service @var{config}
12719 Return a service to run mingetty according to @var{config}, a
12720 @code{<mingetty-configuration>} object, which specifies the tty to run, among
12724 @deftp {Data Type} mingetty-configuration
12725 This is the data type representing the configuration of Mingetty, which
12726 provides the default implementation of virtual console log-in.
12731 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
12733 @item @code{auto-login} (default: @code{#f})
12734 When true, this field must be a string denoting the user name under
12735 which the system automatically logs in. When it is @code{#f}, a
12736 user name and password must be entered to log in.
12738 @item @code{login-program} (default: @code{#f})
12739 This must be either @code{#f}, in which case the default log-in program
12740 is used (@command{login} from the Shadow tool suite), or a gexp denoting
12741 the name of the log-in program.
12743 @item @code{login-pause?} (default: @code{#f})
12744 When set to @code{#t} in conjunction with @var{auto-login}, the user
12745 will have to press a key before the log-in shell is launched.
12747 @item @code{mingetty} (default: @var{mingetty})
12748 The Mingetty package to use.
12753 @deffn {Scheme Procedure} agetty-service @var{config}
12754 Return a service to run agetty according to @var{config}, an
12755 @code{<agetty-configuration>} object, which specifies the tty to run,
12756 among other things.
12759 @deftp {Data Type} agetty-configuration
12760 This is the data type representing the configuration of agetty, which
12761 implements virtual and serial console log-in. See the @code{agetty(8)}
12762 man page for more information.
12767 The name of the console this agetty runs on, as a string---e.g.,
12768 @code{"ttyS0"}. This argument is optional, it will default to
12769 a reasonable default serial port used by the kernel Linux.
12771 For this, if there is a value for an option @code{agetty.tty} in the kernel
12772 command line, agetty will extract the device name of the serial port
12773 from it and use that.
12775 If not and if there is a value for an option @code{console} with a tty in
12776 the Linux command line, agetty will extract the device name of the
12777 serial port from it and use that.
12779 In both cases, agetty will leave the other serial device settings
12780 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
12783 @item @code{baud-rate} (default: @code{#f})
12784 A string containing a comma-separated list of one or more baud rates, in
12787 @item @code{term} (default: @code{#f})
12788 A string containing the value used for the @env{TERM} environment
12791 @item @code{eight-bits?} (default: @code{#f})
12792 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
12795 @item @code{auto-login} (default: @code{#f})
12796 When passed a login name, as a string, the specified user will be logged
12797 in automatically without prompting for their login name or password.
12799 @item @code{no-reset?} (default: @code{#f})
12800 When @code{#t}, don't reset terminal cflags (control modes).
12802 @item @code{host} (default: @code{#f})
12803 This accepts a string containing the ``login_host'', which will be written
12804 into the @file{/var/run/utmpx} file.
12806 @item @code{remote?} (default: @code{#f})
12807 When set to @code{#t} in conjunction with @var{host}, this will add an
12808 @code{-r} fakehost option to the command line of the login program
12809 specified in @var{login-program}.
12811 @item @code{flow-control?} (default: @code{#f})
12812 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
12814 @item @code{no-issue?} (default: @code{#f})
12815 When set to @code{#t}, the contents of the @file{/etc/issue} file will
12816 not be displayed before presenting the login prompt.
12818 @item @code{init-string} (default: @code{#f})
12819 This accepts a string that will be sent to the tty or modem before
12820 sending anything else. It can be used to initialize a modem.
12822 @item @code{no-clear?} (default: @code{#f})
12823 When set to @code{#t}, agetty will not clear the screen before showing
12826 @item @code{login-program} (default: (file-append shadow "/bin/login"))
12827 This must be either a gexp denoting the name of a log-in program, or
12828 unset, in which case the default value is the @command{login} from the
12831 @item @code{local-line} (default: @code{#f})
12832 Control the CLOCAL line flag. This accepts one of three symbols as
12833 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
12834 the default value chosen by agetty is @code{'auto}.
12836 @item @code{extract-baud?} (default: @code{#f})
12837 When set to @code{#t}, instruct agetty to try to extract the baud rate
12838 from the status messages produced by certain types of modems.
12840 @item @code{skip-login?} (default: @code{#f})
12841 When set to @code{#t}, do not prompt the user for a login name. This
12842 can be used with @var{login-program} field to use non-standard login
12845 @item @code{no-newline?} (default: @code{#f})
12846 When set to @code{#t}, do not print a newline before printing the
12847 @file{/etc/issue} file.
12849 @c Is this dangerous only when used with login-program, or always?
12850 @item @code{login-options} (default: @code{#f})
12851 This option accepts a string containing options that are passed to the
12852 login program. When used with the @var{login-program}, be aware that a
12853 malicious user could try to enter a login name containing embedded
12854 options that could be parsed by the login program.
12856 @item @code{login-pause} (default: @code{#f})
12857 When set to @code{#t}, wait for any key before showing the login prompt.
12858 This can be used in conjunction with @var{auto-login} to save memory by
12859 lazily spawning shells.
12861 @item @code{chroot} (default: @code{#f})
12862 Change root to the specified directory. This option accepts a directory
12865 @item @code{hangup?} (default: @code{#f})
12866 Use the Linux system call @code{vhangup} to do a virtual hangup of the
12867 specified terminal.
12869 @item @code{keep-baud?} (default: @code{#f})
12870 When set to @code{#t}, try to keep the existing baud rate. The baud
12871 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
12874 @item @code{timeout} (default: @code{#f})
12875 When set to an integer value, terminate if no user name could be read
12876 within @var{timeout} seconds.
12878 @item @code{detect-case?} (default: @code{#f})
12879 When set to @code{#t}, turn on support for detecting an uppercase-only
12880 terminal. This setting will detect a login name containing only
12881 uppercase letters as indicating an uppercase-only terminal and turn on
12882 some upper-to-lower case conversions. Note that this will not support
12883 Unicode characters.
12885 @item @code{wait-cr?} (default: @code{#f})
12886 When set to @code{#t}, wait for the user or modem to send a
12887 carriage-return or linefeed character before displaying
12888 @file{/etc/issue} or login prompt. This is typically used with the
12889 @var{init-string} option.
12891 @item @code{no-hints?} (default: @code{#f})
12892 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
12895 @item @code{no-hostname?} (default: @code{#f})
12896 By default, the hostname is printed. When this option is set to
12897 @code{#t}, no hostname will be shown at all.
12899 @item @code{long-hostname?} (default: @code{#f})
12900 By default, the hostname is only printed until the first dot. When this
12901 option is set to @code{#t}, the fully qualified hostname by
12902 @code{gethostname} or @code{getaddrinfo} is shown.
12904 @item @code{erase-characters} (default: @code{#f})
12905 This option accepts a string of additional characters that should be
12906 interpreted as backspace when the user types their login name.
12908 @item @code{kill-characters} (default: @code{#f})
12909 This option accepts a string that should be interpreted to mean ``ignore
12910 all previous characters'' (also called a ``kill'' character) when the user
12911 types their login name.
12913 @item @code{chdir} (default: @code{#f})
12914 This option accepts, as a string, a directory path that will be changed
12917 @item @code{delay} (default: @code{#f})
12918 This options accepts, as an integer, the number of seconds to sleep
12919 before opening the tty and displaying the login prompt.
12921 @item @code{nice} (default: @code{#f})
12922 This option accepts, as an integer, the nice value with which to run the
12923 @command{login} program.
12925 @item @code{extra-options} (default: @code{'()})
12926 This option provides an ``escape hatch'' for the user to provide arbitrary
12927 command-line arguments to @command{agetty} as a list of strings.
12932 @deffn {Scheme Procedure} kmscon-service-type @var{config}
12933 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
12934 according to @var{config}, a @code{<kmscon-configuration>} object, which
12935 specifies the tty to run, among other things.
12938 @deftp {Data Type} kmscon-configuration
12939 This is the data type representing the configuration of Kmscon, which
12940 implements virtual console log-in.
12944 @item @code{virtual-terminal}
12945 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
12947 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
12948 A gexp denoting the name of the log-in program. The default log-in program is
12949 @command{login} from the Shadow tool suite.
12951 @item @code{login-arguments} (default: @code{'("-p")})
12952 A list of arguments to pass to @command{login}.
12954 @item @code{auto-login} (default: @code{#f})
12955 When passed a login name, as a string, the specified user will be logged
12956 in automatically without prompting for their login name or password.
12958 @item @code{hardware-acceleration?} (default: #f)
12959 Whether to use hardware acceleration.
12961 @item @code{kmscon} (default: @var{kmscon})
12962 The Kmscon package to use.
12967 @cindex name service cache daemon
12969 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
12970 [#:name-services '()]
12971 Return a service that runs the libc name service cache daemon (nscd) with the
12972 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
12973 Service Switch}, for an example.
12975 For convenience, the Shepherd service for nscd provides the following actions:
12979 @cindex cache invalidation, nscd
12980 @cindex nscd, cache invalidation
12981 This invalidate the given cache. For instance, running:
12984 herd invalidate nscd hosts
12988 invalidates the host name lookup cache of nscd.
12991 Running @command{herd statistics nscd} displays information about nscd usage
12997 @defvr {Scheme Variable} %nscd-default-configuration
12998 This is the default @code{<nscd-configuration>} value (see below) used
12999 by @code{nscd-service}. It uses the caches defined by
13000 @code{%nscd-default-caches}; see below.
13003 @deftp {Data Type} nscd-configuration
13004 This is the data type representing the name service cache daemon (nscd)
13009 @item @code{name-services} (default: @code{'()})
13010 List of packages denoting @dfn{name services} that must be visible to
13011 the nscd---e.g., @code{(list @var{nss-mdns})}.
13013 @item @code{glibc} (default: @var{glibc})
13014 Package object denoting the GNU C Library providing the @command{nscd}
13017 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
13018 Name of the nscd log file. This is where debugging output goes when
13019 @code{debug-level} is strictly positive.
13021 @item @code{debug-level} (default: @code{0})
13022 Integer denoting the debugging levels. Higher numbers mean that more
13023 debugging output is logged.
13025 @item @code{caches} (default: @code{%nscd-default-caches})
13026 List of @code{<nscd-cache>} objects denoting things to be cached; see
13032 @deftp {Data Type} nscd-cache
13033 Data type representing a cache database of nscd and its parameters.
13037 @item @code{database}
13038 This is a symbol representing the name of the database to be cached.
13039 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
13040 @code{services}, which designate the corresponding NSS database
13041 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
13043 @item @code{positive-time-to-live}
13044 @itemx @code{negative-time-to-live} (default: @code{20})
13045 A number representing the number of seconds during which a positive or
13046 negative lookup result remains in cache.
13048 @item @code{check-files?} (default: @code{#t})
13049 Whether to check for updates of the files corresponding to
13052 For instance, when @var{database} is @code{hosts}, setting this flag
13053 instructs nscd to check for updates in @file{/etc/hosts} and to take
13056 @item @code{persistent?} (default: @code{#t})
13057 Whether the cache should be stored persistently on disk.
13059 @item @code{shared?} (default: @code{#t})
13060 Whether the cache should be shared among users.
13062 @item @code{max-database-size} (default: 32@tie{}MiB)
13063 Maximum size in bytes of the database cache.
13065 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
13066 @c settings, so leave them out.
13071 @defvr {Scheme Variable} %nscd-default-caches
13072 List of @code{<nscd-cache>} objects used by default by
13073 @code{nscd-configuration} (see above).
13075 It enables persistent and aggressive caching of service and host name
13076 lookups. The latter provides better host name lookup performance,
13077 resilience in the face of unreliable name servers, and also better
13078 privacy---often the result of host name lookups is in local cache, so
13079 external name servers do not even need to be queried.
13082 @anchor{syslog-configuration-type}
13085 @deftp {Data Type} syslog-configuration
13086 This data type represents the configuration of the syslog daemon.
13089 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
13090 The syslog daemon to use.
13092 @item @code{config-file} (default: @code{%default-syslog.conf})
13093 The syslog configuration file to use.
13098 @anchor{syslog-service}
13100 @deffn {Scheme Procedure} syslog-service @var{config}
13101 Return a service that runs a syslog daemon according to @var{config}.
13103 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
13104 information on the configuration file syntax.
13107 @defvr {Scheme Variable} guix-service-type
13108 This is the type of the service that runs the build daemon,
13109 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
13110 @code{guix-configuration} record as described below.
13113 @anchor{guix-configuration-type}
13114 @deftp {Data Type} guix-configuration
13115 This data type represents the configuration of the Guix build daemon.
13116 @xref{Invoking guix-daemon}, for more information.
13119 @item @code{guix} (default: @var{guix})
13120 The Guix package to use.
13122 @item @code{build-group} (default: @code{"guixbuild"})
13123 Name of the group for build user accounts.
13125 @item @code{build-accounts} (default: @code{10})
13126 Number of build user accounts to create.
13128 @item @code{authorize-key?} (default: @code{#t})
13129 @cindex substitutes, authorization thereof
13130 Whether to authorize the substitute keys listed in
13131 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
13132 (@pxref{Substitutes}).
13134 @vindex %default-authorized-guix-keys
13135 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
13136 The list of authorized key files for archive imports, as a list of
13137 string-valued gexps (@pxref{Invoking guix archive}). By default, it
13138 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
13140 @item @code{use-substitutes?} (default: @code{#t})
13141 Whether to use substitutes.
13143 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
13144 The list of URLs where to look for substitutes by default.
13146 @item @code{max-silent-time} (default: @code{0})
13147 @itemx @code{timeout} (default: @code{0})
13148 The number of seconds of silence and the number of seconds of activity,
13149 respectively, after which a build process times out. A value of zero
13150 disables the timeout.
13152 @item @code{log-compression} (default: @code{'bzip2})
13153 The type of compression used for build logs---one of @code{gzip},
13154 @code{bzip2}, or @code{none}.
13156 @item @code{extra-options} (default: @code{'()})
13157 List of extra command-line options for @command{guix-daemon}.
13159 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
13160 File where @command{guix-daemon}'s standard output and standard error
13163 @cindex HTTP proxy, for @code{guix-daemon}
13164 @cindex proxy, for @code{guix-daemon} HTTP access
13165 @item @code{http-proxy} (default: @code{#f})
13166 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
13167 derivations and substitutes.
13169 It is also possible to change the daemon's proxy at run time through the
13170 @code{set-http-proxy} action, which restarts it:
13173 herd set-http-proxy guix-daemon http://localhost:8118
13176 To clear the proxy settings, run:
13179 herd set-http-proxy guix-daemon
13182 @item @code{tmpdir} (default: @code{#f})
13183 A directory path where the @command{guix-daemon} will perform builds.
13188 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
13189 Run @var{udev}, which populates the @file{/dev} directory dynamically.
13190 udev rules can be provided as a list of files through the @var{rules}
13191 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
13192 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
13193 creation of such rule files.
13195 The @command{herd rules udev} command, as root, returns the name of the
13196 directory containing all the active udev rules.
13199 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
13200 Return a udev-rule file named @var{file-name} containing the rules
13201 defined by the @var{contents} literal.
13203 In the following example, a rule for a USB device is defined to be
13204 stored in the file @file{90-usb-thing.rules}. The rule runs a script
13205 upon detecting a USB device with a given product identifier.
13208 (define %example-udev-rule
13210 "90-usb-thing.rules"
13211 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
13212 "ATTR@{product@}==\"Example\", "
13213 "RUN+=\"/path/to/script\"")))
13217 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
13218 [#:groups @var{groups}]
13219 Return a service that extends @code{udev-service-type } with @var{rules}
13220 and @code{account-service-type} with @var{groups} as system groups.
13221 This works by creating a singleton service type
13222 @code{@var{name}-udev-rules}, of which the returned service is an
13225 Here we show how it can be used to extend @code{udev-service-type} with the
13226 previously defined rule @code{%example-udev-rule}.
13232 (cons (udev-rules-service 'usb-thing %example-udev-rule)
13233 %desktop-services)))
13237 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
13238 Return a udev file named @var{file-name} containing the rules defined
13239 within @var{file}, a file-like object.
13241 The following example showcases how we can use an existing rule file.
13244 (use-modules (guix download) ;for url-fetch
13245 (guix packages) ;for origin
13248 (define %android-udev-rules
13250 "51-android-udev.rules"
13251 (let ((version "20170910"))
13254 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
13255 "android-udev-rules/" version "/51-android.rules"))
13257 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
13261 Additionally, Guix package definitions can be included in @var{rules} in
13262 order to extend the udev rules with the definitions found under their
13263 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
13264 @var{file->udev-rule} example, we could have used the
13265 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
13266 packages android)} module.
13268 The following example shows how to use the @var{android-udev-rules}
13269 package so that the Android tool @command{adb} can detect devices
13270 without root privileges. It also details how to create the
13271 @code{adbusers} group, which is required for the proper functioning of
13272 the rules defined within the @code{android-udev-rules} package. To
13273 create such a group, we must define it both as part of the
13274 @code{supplementary-groups} of our @code{user-account} declaration, as
13275 well as in the @var{groups} of the @code{udev-rules-service} procedure.
13278 (use-modules (gnu packages android) ;for android-udev-rules
13279 (gnu system shadow) ;for user-group
13284 (users (cons (user-account
13286 (supplementary-groups
13287 '("adbusers" ;for adb
13288 "wheel" "netdev" "audio" "video")))))
13291 (cons (udev-rules-service 'android android-udev-rules
13292 #:groups '("adbusers"))
13293 %desktop-services)))
13296 @defvr {Scheme Variable} urandom-seed-service-type
13297 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
13298 when rebooting. It also tries to seed @file{/dev/urandom} from
13299 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
13303 @defvr {Scheme Variable} %random-seed-file
13304 This is the name of the file where some random bytes are saved by
13305 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
13306 It defaults to @file{/var/lib/random-seed}.
13311 @defvr {Scheme Variable} gpm-service-type
13312 This is the type of the service that runs GPM, the @dfn{general-purpose
13313 mouse daemon}, which provides mouse support to the Linux console. GPM
13314 allows users to use the mouse in the console, notably to select, copy,
13317 The value for services of this type must be a @code{gpm-configuration}
13318 (see below). This service is not part of @code{%base-services}.
13321 @deftp {Data Type} gpm-configuration
13322 Data type representing the configuration of GPM.
13325 @item @code{options} (default: @code{%default-gpm-options})
13326 Command-line options passed to @command{gpm}. The default set of
13327 options instruct @command{gpm} to listen to mouse events on
13328 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
13331 @item @code{gpm} (default: @code{gpm})
13332 The GPM package to use.
13337 @anchor{guix-publish-service-type}
13338 @deffn {Scheme Variable} guix-publish-service-type
13339 This is the service type for @command{guix publish} (@pxref{Invoking
13340 guix publish}). Its value must be a @code{guix-publish-configuration}
13341 object, as described below.
13343 This assumes that @file{/etc/guix} already contains a signing key pair as
13344 created by @command{guix archive --generate-key} (@pxref{Invoking guix
13345 archive}). If that is not the case, the service will fail to start.
13348 @deftp {Data Type} guix-publish-configuration
13349 Data type representing the configuration of the @code{guix publish}
13353 @item @code{guix} (default: @code{guix})
13354 The Guix package to use.
13356 @item @code{port} (default: @code{80})
13357 The TCP port to listen for connections.
13359 @item @code{host} (default: @code{"localhost"})
13360 The host (and thus, network interface) to listen to. Use
13361 @code{"0.0.0.0"} to listen on all the network interfaces.
13363 @item @code{compression} (default: @code{'(("gzip" 3))})
13364 This is a list of compression method/level tuple used when compressing
13365 substitutes. For example, to compress all substitutes with @emph{both} lzip
13366 at level 7 and gzip at level 9, write:
13369 '(("lzip" 7) ("gzip" 9))
13372 Level 9 achieves the best compression ratio at the expense of increased CPU
13373 usage, whereas level 1 achieves fast compression.
13375 An empty list disables compression altogether.
13377 @item @code{nar-path} (default: @code{"nar"})
13378 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
13379 publish, @option{--nar-path}}, for details.
13381 @item @code{cache} (default: @code{#f})
13382 When it is @code{#f}, disable caching and instead generate archives on
13383 demand. Otherwise, this should be the name of a directory---e.g.,
13384 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
13385 archives and meta-data ready to be sent. @xref{Invoking guix publish,
13386 @option{--cache}}, for more information on the tradeoffs involved.
13388 @item @code{workers} (default: @code{#f})
13389 When it is an integer, this is the number of worker threads used for
13390 caching; when @code{#f}, the number of processors is used.
13391 @xref{Invoking guix publish, @option{--workers}}, for more information.
13393 @item @code{ttl} (default: @code{#f})
13394 When it is an integer, this denotes the @dfn{time-to-live} in seconds
13395 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
13396 for more information.
13400 @anchor{rngd-service}
13401 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
13402 [#:device "/dev/hwrng"]
13403 Return a service that runs the @command{rngd} program from @var{rng-tools}
13404 to add @var{device} to the kernel's entropy pool. The service will fail if
13405 @var{device} does not exist.
13408 @anchor{pam-limits-service}
13409 @cindex session limits
13414 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
13416 Return a service that installs a configuration file for the
13417 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
13418 @code{pam_limits} module}. The procedure optionally takes a list of
13419 @code{pam-limits-entry} values, which can be used to specify
13420 @code{ulimit} limits and nice priority limits to user sessions.
13422 The following limits definition sets two hard and soft limits for all
13423 login sessions of users in the @code{realtime} group:
13426 (pam-limits-service
13428 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
13429 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
13432 The first entry increases the maximum realtime priority for
13433 non-privileged processes; the second entry lifts any restriction of the
13434 maximum address space that can be locked in memory. These settings are
13435 commonly used for real-time audio systems.
13438 @node Scheduled Job Execution
13439 @subsection Scheduled Job Execution
13443 @cindex scheduling jobs
13444 The @code{(gnu services mcron)} module provides an interface to
13445 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
13446 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
13447 Unix @command{cron} daemon; the main difference is that it is
13448 implemented in Guile Scheme, which provides a lot of flexibility when
13449 specifying the scheduling of jobs and their actions.
13451 The example below defines an operating system that runs the
13452 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
13453 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
13454 well as the @command{mkid} command on behalf of an unprivileged user
13455 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
13456 gexps to introduce job definitions that are passed to mcron
13457 (@pxref{G-Expressions}).
13460 (use-modules (guix) (gnu) (gnu services mcron))
13461 (use-package-modules base idutils)
13463 (define updatedb-job
13464 ;; Run 'updatedb' at 3AM every day. Here we write the
13465 ;; job's action as a Scheme procedure.
13466 #~(job '(next-hour '(3))
13468 (execl (string-append #$findutils "/bin/updatedb")
13470 "--prunepaths=/tmp /var/tmp /gnu/store"))))
13472 (define garbage-collector-job
13473 ;; Collect garbage 5 minutes after midnight every day.
13474 ;; The job's action is a shell command.
13475 #~(job "5 0 * * *" ;Vixie cron syntax
13478 (define idutils-job
13479 ;; Update the index database as user "charlie" at 12:15PM
13480 ;; and 19:15PM. This runs from the user's home directory.
13481 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
13482 (string-append #$idutils "/bin/mkid src")
13487 (services (cons (service mcron-service-type
13488 (mcron-configuration
13489 (jobs (list garbage-collector-job
13495 For more complex jobs defined in Scheme where you need control over the top
13496 level, for instance to introduce a @code{use-modules} form, you can move your
13497 code to a separate program using the @code{program-file} procedure of the
13498 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
13502 (define %battery-alert-job
13503 ;; Beep when the battery percentage falls below %MIN-LEVEL.
13505 '(next-minute (range 0 60 1))
13507 "battery-alert.scm"
13508 (with-imported-modules (source-module-closure
13509 '((guix build utils)))
13511 (define %min-level 20)
13512 (use-modules (guix build utils)
13515 (ice-9 textual-ports)
13517 (setenv "LC_ALL" "C") ;ensure English output
13518 (and-let* ((input-pipe (open-pipe*
13520 #$(file-append acpi "/bin/acpi")))
13521 (output (get-string-all input-pipe))
13522 (m (string-match "Discharging, ([0-9]+)%" output))
13523 (level (string->number (match:substring m 1)))
13524 ((< level %min-level)))
13525 (format #t "warning: Battery level is low (~a%)~%" level)
13526 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
13529 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
13530 for more information on mcron job specifications. Below is the
13531 reference of the mcron service.
13533 On a running system, you can use the @code{schedule} action of the service to
13534 visualize the mcron jobs that will be executed next:
13537 # herd schedule mcron
13541 The example above lists the next five tasks that will be executed, but you can
13542 also specify the number of tasks to display:
13545 # herd schedule mcron 10
13548 @defvr {Scheme Variable} mcron-service-type
13549 This is the type of the @code{mcron} service, whose value is an
13550 @code{mcron-configuration} object.
13552 This service type can be the target of a service extension that provides
13553 it additional job specifications (@pxref{Service Composition}). In
13554 other words, it is possible to define services that provide additional
13558 @deftp {Data Type} mcron-configuration
13559 Data type representing the configuration of mcron.
13562 @item @code{mcron} (default: @var{mcron})
13563 The mcron package to use.
13566 This is a list of gexps (@pxref{G-Expressions}), where each gexp
13567 corresponds to an mcron job specification (@pxref{Syntax, mcron job
13568 specifications,, mcron, GNU@tie{}mcron}).
13574 @subsection Log Rotation
13577 @cindex log rotation
13579 Log files such as those found in @file{/var/log} tend to grow endlessly,
13580 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
13581 their contents in separate files, possibly compressed. The @code{(gnu
13582 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
13583 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
13585 This service is part of @code{%base-services}, and thus enabled by
13586 default, with the default settings, for commonly encountered log files.
13587 The example below shows how to extend it with an additional
13588 @dfn{rotation}, should you need to do that (usually, services that
13589 produce log files already take care of that):
13592 (use-modules (guix) (gnu))
13593 (use-service-modules admin)
13595 (define my-log-files
13596 ;; Log files that I want to rotate.
13597 '("/var/log/something.log" "/var/log/another.log"))
13601 (services (cons (simple-service 'rotate-my-stuff
13602 rottlog-service-type
13603 (list (log-rotation
13605 (files my-log-files))))
13609 @defvr {Scheme Variable} rottlog-service-type
13610 This is the type of the Rottlog service, whose value is a
13611 @code{rottlog-configuration} object.
13613 Other services can extend this one with new @code{log-rotation} objects
13614 (see below), thereby augmenting the set of files to be rotated.
13616 This service type can define mcron jobs (@pxref{Scheduled Job
13617 Execution}) to run the rottlog service.
13620 @deftp {Data Type} rottlog-configuration
13621 Data type representing the configuration of rottlog.
13624 @item @code{rottlog} (default: @code{rottlog})
13625 The Rottlog package to use.
13627 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
13628 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
13629 rottlog, GNU Rot[t]log Manual}).
13631 @item @code{rotations} (default: @code{%default-rotations})
13632 A list of @code{log-rotation} objects as defined below.
13635 This is a list of gexps where each gexp corresponds to an mcron job
13636 specification (@pxref{Scheduled Job Execution}).
13640 @deftp {Data Type} log-rotation
13641 Data type representing the rotation of a group of log files.
13643 Taking an example from the Rottlog manual (@pxref{Period Related File
13644 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
13650 (files '("/var/log/apache/*"))
13651 (options '("storedir apache-archives"
13657 The list of fields is as follows:
13660 @item @code{frequency} (default: @code{'weekly})
13661 The log rotation frequency, a symbol.
13664 The list of files or file glob patterns to rotate.
13666 @item @code{options} (default: @code{'()})
13667 The list of rottlog options for this rotation (@pxref{Configuration
13668 parameters,,, rottlog, GNU Rot[t]lg Manual}).
13670 @item @code{post-rotate} (default: @code{#f})
13671 Either @code{#f} or a gexp to execute once the rotation has completed.
13675 @defvr {Scheme Variable} %default-rotations
13676 Specifies weekly rotation of @code{%rotated-files} and of
13677 @file{/var/log/guix-daemon.log}.
13680 @defvr {Scheme Variable} %rotated-files
13681 The list of syslog-controlled files to be rotated. By default it is:
13682 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
13683 "/var/log/maillog")}.
13686 @node Networking Services
13687 @subsection Networking Services
13689 The @code{(gnu services networking)} module provides services to configure
13690 the network interface.
13692 @cindex DHCP, networking service
13693 @defvr {Scheme Variable} dhcp-client-service-type
13694 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
13695 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
13696 is the DHCP client package to use, @code{isc-dhcp} by default.
13699 @deffn {Scheme Procedure} dhcpd-service-type
13700 This type defines a service that runs a DHCP daemon. To create a
13701 service of this type, you must supply a @code{<dhcpd-configuration>}.
13705 (service dhcpd-service-type
13706 (dhcpd-configuration
13707 (config-file (local-file "my-dhcpd.conf"))
13708 (interfaces '("enp0s25"))))
13712 @deftp {Data Type} dhcpd-configuration
13714 @item @code{package} (default: @code{isc-dhcp})
13715 The package that provides the DHCP daemon. This package is expected to
13716 provide the daemon at @file{sbin/dhcpd} relative to its output
13717 directory. The default package is the
13718 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
13719 @item @code{config-file} (default: @code{#f})
13720 The configuration file to use. This is required. It will be passed to
13721 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
13722 object (@pxref{G-Expressions, file-like objects}). See @code{man
13723 dhcpd.conf} for details on the configuration file syntax.
13724 @item @code{version} (default: @code{"4"})
13725 The DHCP version to use. The ISC DHCP server supports the values ``4'',
13726 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
13727 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
13729 @item @code{run-directory} (default: @code{"/run/dhcpd"})
13730 The run directory to use. At service activation time, this directory
13731 will be created if it does not exist.
13732 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
13733 The PID file to use. This corresponds to the @code{-pf} option of
13734 @code{dhcpd}. See @code{man dhcpd} for details.
13735 @item @code{interfaces} (default: @code{'()})
13736 The names of the network interfaces on which dhcpd should listen for
13737 broadcasts. If this list is not empty, then its elements (which must be
13738 strings) will be appended to the @code{dhcpd} invocation when starting
13739 the daemon. It may not be necessary to explicitly specify any
13740 interfaces here; see @code{man dhcpd} for details.
13744 @defvr {Scheme Variable} static-networking-service-type
13745 This is the type for statically-configured network interfaces.
13746 @c TODO Document <static-networking> data structures.
13749 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
13750 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
13751 [#:requirement @code{'(udev)}]
13752 Return a service that starts @var{interface} with address @var{ip}. If
13753 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
13754 it must be a string specifying the default network gateway. @var{requirement}
13755 can be used to declare a dependency on another service before configuring the
13758 This procedure can be called several times, one for each network
13759 interface of interest. Behind the scenes what it does is extend
13760 @code{static-networking-service-type} with additional network interfaces
13766 (static-networking-service "eno1" "192.168.1.82"
13767 #:gateway "192.168.1.2"
13768 #:name-servers '("192.168.1.2"))
13775 @cindex network management
13776 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
13777 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
13778 management daemon that aims to simplify wired and wireless networking.
13780 This service adds the @var{wicd} package to the global profile, providing
13781 several commands to interact with the daemon and configure networking:
13782 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
13783 and @command{wicd-curses} user interfaces.
13786 @cindex ModemManager
13788 @defvr {Scheme Variable} modem-manager-service-type
13789 This is the service type for the
13790 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
13791 service. The value for this service type is a
13792 @code{modem-manager-configuration} record.
13794 This service is part of @code{%desktop-services} (@pxref{Desktop
13798 @deftp {Data Type} modem-manager-configuration
13799 Data type representing the configuration of ModemManager.
13802 @item @code{modem-manager} (default: @code{modem-manager})
13803 The ModemManager package to use.
13808 @cindex USB_ModeSwitch
13809 @cindex Modeswitching
13811 @defvr {Scheme Variable} usb-modeswitch-service-type
13812 This is the service type for the
13813 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
13814 value for this service type is a @code{usb-modeswitch-configuration} record.
13816 When plugged in, some USB modems (and other USB devices) initially present
13817 themselves as a read-only storage medium and not as a modem. They need to be
13818 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
13819 installs udev rules to automatically modeswitch these devices when they are
13822 This service is part of @code{%desktop-services} (@pxref{Desktop
13826 @deftp {Data Type} usb-modeswitch-configuration
13827 Data type representing the configuration of USB_ModeSwitch.
13830 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
13831 The USB_ModeSwitch package providing the binaries for modeswitching.
13833 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
13834 The package providing the device data and udev rules file used by
13837 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
13838 Which config file to use for the USB_ModeSwitch dispatcher. By default the
13839 config file shipped with USB_ModeSwitch is used which disables logging to
13840 @file{/var/log} among other default settings. If set to @code{#f}, no config
13846 @cindex NetworkManager
13848 @defvr {Scheme Variable} network-manager-service-type
13849 This is the service type for the
13850 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
13851 service. The value for this service type is a
13852 @code{network-manager-configuration} record.
13854 This service is part of @code{%desktop-services} (@pxref{Desktop
13858 @deftp {Data Type} network-manager-configuration
13859 Data type representing the configuration of NetworkManager.
13862 @item @code{network-manager} (default: @code{network-manager})
13863 The NetworkManager package to use.
13865 @item @code{dns} (default: @code{"default"})
13866 Processing mode for DNS, which affects how NetworkManager uses the
13867 @code{resolv.conf} configuration file.
13871 NetworkManager will update @code{resolv.conf} to reflect the nameservers
13872 provided by currently active connections.
13875 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
13876 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
13877 then update @code{resolv.conf} to point to the local nameserver.
13879 With this setting, you can share your network connection. For example when
13880 you want to share your network connection to another laptop @i{via} an
13881 Ethernet cable, you can open @command{nm-connection-editor} and configure the
13882 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
13883 and reestablish the connection (or reboot).
13885 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
13886 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
13887 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
13888 browser on your host system, or connect to the VM @i{via} SSH
13889 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
13890 host-to-guest connection, run this command once:
13893 nmcli connection add type tun \
13894 connection.interface-name tap0 \
13895 tun.mode tap tun.owner $(id -u) \
13896 ipv4.method shared \
13897 ipv4.addresses 172.28.112.1/24
13900 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
13901 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
13902 @command{qemu-system-...}.
13905 NetworkManager will not modify @code{resolv.conf}.
13908 @item @code{vpn-plugins} (default: @code{'()})
13909 This is the list of available plugins for virtual private networks
13910 (VPNs). An example of this is the @code{network-manager-openvpn}
13911 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
13917 @deffn {Scheme Variable} connman-service-type
13918 This is the service type to run @url{https://01.org/connman,Connman},
13919 a network connection manager.
13921 Its value must be an
13922 @code{connman-configuration} record as in this example:
13925 (service connman-service-type
13926 (connman-configuration
13927 (disable-vpn? #t)))
13930 See below for details about @code{connman-configuration}.
13933 @deftp {Data Type} connman-configuration
13934 Data Type representing the configuration of connman.
13937 @item @code{connman} (default: @var{connman})
13938 The connman package to use.
13940 @item @code{disable-vpn?} (default: @code{#f})
13941 When true, disable connman's vpn plugin.
13945 @cindex WPA Supplicant
13946 @defvr {Scheme Variable} wpa-supplicant-service-type
13947 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
13948 supplicant}, an authentication daemon required to authenticate against
13949 encrypted WiFi or ethernet networks.
13952 @deftp {Data Type} wpa-supplicant-configuration
13953 Data type representing the configuration of WPA Supplicant.
13955 It takes the following parameters:
13958 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
13959 The WPA Supplicant package to use.
13961 @item @code{dbus?} (default: @code{#t})
13962 Whether to listen for requests on D-Bus.
13964 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
13965 Where to store the PID file.
13967 @item @code{interface} (default: @code{#f})
13968 If this is set, it must specify the name of a network interface that
13969 WPA supplicant will control.
13971 @item @code{config-file} (default: @code{#f})
13972 Optional configuration file to use.
13974 @item @code{extra-options} (default: @code{'()})
13975 List of additional command-line arguments to pass to the daemon.
13979 @cindex hostapd service, for Wi-Fi access points
13980 @cindex Wi-Fi access points, hostapd service
13981 @defvr {Scheme Variable} hostapd-service-type
13982 This is the service type to run the @uref{https://w1.fi/hostapd/,
13983 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
13984 authentication servers. Its associated value must be a
13985 @code{hostapd-configuration} as shown below:
13988 ;; Use wlan1 to run the access point for "My Network".
13989 (service hostapd-service-type
13990 (hostapd-configuration
13991 (interface "wlan1")
13992 (ssid "My Network")
13997 @deftp {Data Type} hostapd-configuration
13998 This data type represents the configuration of the hostapd service, with
13999 the following fields:
14002 @item @code{package} (default: @code{hostapd})
14003 The hostapd package to use.
14005 @item @code{interface} (default: @code{"wlan0"})
14006 The network interface to run the WiFi access point.
14009 The SSID (@dfn{service set identifier}), a string that identifies this
14012 @item @code{broadcast-ssid?} (default: @code{#t})
14013 Whether to broadcast this SSID.
14015 @item @code{channel} (default: @code{1})
14016 The WiFi channel to use.
14018 @item @code{driver} (default: @code{"nl80211"})
14019 The driver interface type. @code{"nl80211"} is used with all Linux
14020 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
14021 RADIUS server that does # not control any wireless/wired driver.
14023 @item @code{extra-settings} (default: @code{""})
14024 Extra settings to append as-is to the hostapd configuration file. See
14025 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
14026 configuration file reference.
14030 @defvr {Scheme Variable} simulated-wifi-service-type
14031 This is the type of a service to simulate WiFi networking, which can be
14032 useful in virtual machines for testing purposes. The service loads the
14034 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
14035 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
14036 network that can be seen on @code{wlan0}, by default.
14038 The service's value is a @code{hostapd-configuration} record.
14042 @defvr {Scheme Variable} iptables-service-type
14043 This is the service type to set up an iptables configuration. iptables is a
14044 packet filtering framework supported by the Linux kernel. This service
14045 supports configuring iptables for both IPv4 and IPv6. A simple example
14046 configuration rejecting all incoming connections except those to the ssh port
14050 (service iptables-service-type
14051 (iptables-configuration
14052 (ipv4-rules (plain-file "iptables.rules" "*filter
14056 -A INPUT -p tcp --dport 22 -j ACCEPT
14057 -A INPUT -j REJECT --reject-with icmp-port-unreachable
14060 (ipv6-rules (plain-file "ip6tables.rules" "*filter
14064 -A INPUT -p tcp --dport 22 -j ACCEPT
14065 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
14071 @deftp {Data Type} iptables-configuration
14072 The data type representing the configuration of iptables.
14075 @item @code{iptables} (default: @code{iptables})
14076 The iptables package that provides @code{iptables-restore} and
14077 @code{ip6tables-restore}.
14078 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
14079 The iptables rules to use. It will be passed to @code{iptables-restore}.
14080 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
14082 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
14083 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
14084 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
14090 @defvr {Scheme Variable} nftables-service-type
14091 This is the service type to set up a nftables configuration. nftables is a
14092 netfilter project that aims to replace the existing iptables, ip6tables,
14093 arptables and ebtables framework. It provides a new packet filtering
14094 framework, a new user-space utility @command{nft}, and a compatibility layer
14095 for iptables. This service comes with a default ruleset
14096 @code{%default-nftables-ruleset} that rejecting all incomming connections
14097 except those to the ssh port 22. To use it, simply write:
14100 (service nftables-service-type)
14104 @deftp {Data Type} nftables-configuration
14105 The data type representing the configuration of nftables.
14108 @item @code{package} (default: @code{nftables})
14109 The nftables package that provides @command{nft}.
14110 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
14111 The nftables ruleset to use. This may be any ``file-like'' object
14112 (@pxref{G-Expressions, file-like objects}).
14116 @cindex NTP (Network Time Protocol), service
14117 @cindex ntpd, service for the Network Time Protocol daemon
14118 @cindex real time clock
14119 @defvr {Scheme Variable} ntp-service-type
14120 This is the type of the service running the @uref{https://www.ntp.org,
14121 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
14122 system clock synchronized with that of the specified NTP servers.
14124 The value of this service is an @code{ntpd-configuration} object, as described
14128 @deftp {Data Type} ntp-configuration
14129 This is the data type for the NTP service configuration.
14132 @item @code{servers} (default: @code{%ntp-servers})
14133 This is the list of servers (@code{<ntp-server>} records) with which
14134 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
14137 @item @code{allow-large-adjustment?} (default: @code{#t})
14138 This determines whether @command{ntpd} is allowed to make an initial
14139 adjustment of more than 1,000 seconds.
14141 @item @code{ntp} (default: @code{ntp})
14142 The NTP package to use.
14146 @defvr {Scheme Variable} %ntp-servers
14147 List of host names used as the default NTP servers. These are servers of the
14148 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
14151 @deftp {Data Type} ntp-server
14152 The data type representing the configuration of a NTP server.
14155 @item @code{type} (default: @code{'server})
14156 The type of the NTP server, given as a symbol. One of @code{'pool},
14157 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
14159 @item @code{address}
14160 The address of the server, as a string.
14162 @item @code{options}
14163 NTPD options to use with that specific server, given as a list of option names
14164 and/or of option names and values tuples. The following example define a server
14165 to use with the options @option{iburst} and @option{prefer}, as well as
14166 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
14171 (address "some.ntp.server.org")
14172 (options `(iburst (version 3) (maxpoll 16) prefer))))
14178 @deffn {Scheme Procedure} openntpd-service-type
14179 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
14180 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
14181 clock synchronized with that of the given servers.
14185 openntpd-service-type
14186 (openntpd-configuration
14187 (listen-on '("127.0.0.1" "::1"))
14188 (sensor '("udcf0 correction 70000"))
14189 (constraint-from '("www.gnu.org"))
14190 (constraints-from '("https://www.google.com/"))
14191 (allow-large-adjustment? #t)))
14196 @defvr {Scheme Variable} %openntpd-servers
14197 This variable is a list of the server addresses defined in
14198 @code{%ntp-servers}.
14201 @deftp {Data Type} openntpd-configuration
14203 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
14204 The openntpd executable to use.
14205 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
14206 A list of local IP addresses or hostnames the ntpd daemon should listen on.
14207 @item @code{query-from} (default: @code{'()})
14208 A list of local IP address the ntpd daemon should use for outgoing queries.
14209 @item @code{sensor} (default: @code{'()})
14210 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
14211 will listen to each sensor that actually exists and ignore non-existent ones.
14212 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
14214 @item @code{server} (default: @code{'()})
14215 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
14216 @item @code{servers} (default: @code{%openntp-servers})
14217 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
14218 @item @code{constraint-from} (default: @code{'()})
14219 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
14220 This time information is not used for precision but acts as an authenticated
14221 constraint, thereby reducing the impact of unauthenticated NTP
14222 man-in-the-middle attacks.
14223 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
14225 @item @code{constraints-from} (default: @code{'()})
14226 As with constraint from, specify a list of URLs, IP addresses or hostnames of
14227 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
14228 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
14229 @item @code{allow-large-adjustment?} (default: @code{#f})
14230 Determines if @code{ntpd} is allowed to make an initial adjustment of more
14236 @deffn {Scheme variable} inetd-service-type
14237 This service runs the @command{inetd} (@pxref{inetd invocation,,,
14238 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
14239 connections on internet sockets, and lazily starts the specified server
14240 program when a connection is made on one of these sockets.
14242 The value of this service is an @code{inetd-configuration} object. The
14243 following example configures the @command{inetd} daemon to provide the
14244 built-in @command{echo} service, as well as an smtp service which
14245 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
14246 gateway @code{hostname}:
14251 (inetd-configuration
14255 (socket-type 'stream)
14262 (socket-type 'stream)
14266 (program (file-append openssh "/bin/ssh"))
14268 '("ssh" "-qT" "-i" "/path/to/ssh_key"
14269 "-W" "smtp-server:25" "user@@hostname")))))))
14272 See below for more details about @code{inetd-configuration}.
14275 @deftp {Data Type} inetd-configuration
14276 Data type representing the configuration of @command{inetd}.
14279 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
14280 The @command{inetd} executable to use.
14282 @item @code{entries} (default: @code{'()})
14283 A list of @command{inetd} service entries. Each entry should be created
14284 by the @code{inetd-entry} constructor.
14288 @deftp {Data Type} inetd-entry
14289 Data type representing an entry in the @command{inetd} configuration.
14290 Each entry corresponds to a socket where @command{inetd} will listen for
14294 @item @code{node} (default: @code{#f})
14295 Optional string, a comma-separated list of local addresses
14296 @command{inetd} should use when listening for this service.
14297 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
14298 description of all options.
14300 A string, the name must correspond to an entry in @code{/etc/services}.
14301 @item @code{socket-type}
14302 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
14304 @item @code{protocol}
14305 A string, must correspond to an entry in @code{/etc/protocols}.
14306 @item @code{wait?} (default: @code{#t})
14307 Whether @command{inetd} should wait for the server to exit before
14308 listening to new service requests.
14310 A string containing the user (and, optionally, group) name of the user
14311 as whom the server should run. The group name can be specified in a
14312 suffix, separated by a colon or period, i.e.@: @code{"user"},
14313 @code{"user:group"} or @code{"user.group"}.
14314 @item @code{program} (default: @code{"internal"})
14315 The server program which will serve the requests, or @code{"internal"}
14316 if @command{inetd} should use a built-in service.
14317 @item @code{arguments} (default: @code{'()})
14318 A list strings or file-like objects, which are the server program's
14319 arguments, starting with the zeroth argument, i.e.@: the name of the
14320 program itself. For @command{inetd}'s internal services, this entry
14321 must be @code{'()} or @code{'("internal")}.
14324 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
14325 detailed discussion of each configuration field.
14329 @defvr {Scheme Variable} tor-service-type
14330 This is the type for a service that runs the @uref{https://torproject.org,
14331 Tor} anonymous networking daemon. The service is configured using a
14332 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
14333 @code{tor} unprivileged user, which is a member of the @code{tor} group.
14337 @deftp {Data Type} tor-configuration
14339 @item @code{tor} (default: @code{tor})
14340 The package that provides the Tor daemon. This package is expected to provide
14341 the daemon at @file{bin/tor} relative to its output directory. The default
14342 package is the @uref{https://www.torproject.org, Tor Project's}
14345 @item @code{config-file} (default: @code{(plain-file "empty" "")})
14346 The configuration file to use. It will be appended to a default configuration
14347 file, and the final configuration file will be passed to @code{tor} via its
14348 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
14349 file-like objects}). See @code{man tor} for details on the configuration file
14352 @item @code{hidden-services} (default: @code{'()})
14353 The list of @code{<hidden-service>} records to use. For any hidden service
14354 you include in this list, appropriate configuration to enable the hidden
14355 service will be automatically added to the default configuration file. You
14356 may conveniently create @code{<hidden-service>} records using the
14357 @code{tor-hidden-service} procedure described below.
14359 @item @code{socks-socket-type} (default: @code{'tcp})
14360 The default socket type that Tor should use for its SOCKS socket. This must
14361 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
14362 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
14363 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
14364 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
14367 If you want to customize the SOCKS socket in more detail, leave
14368 @code{socks-socket-type} at its default value of @code{'tcp} and use
14369 @code{config-file} to override the default by providing your own
14370 @code{SocksPort} option.
14374 @cindex hidden service
14375 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
14376 Define a new Tor @dfn{hidden service} called @var{name} and implementing
14377 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
14380 '((22 "127.0.0.1:22")
14381 (80 "127.0.0.1:8080"))
14384 In this example, port 22 of the hidden service is mapped to local port 22, and
14385 port 80 is mapped to local port 8080.
14387 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
14388 the @file{hostname} file contains the @code{.onion} host name for the hidden
14391 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
14392 project's documentation} for more information.
14395 The @code{(gnu services rsync)} module provides the following services:
14397 You might want an rsync daemon if you have files that you want available
14398 so anyone (or just yourself) can download existing files or upload new
14401 @deffn {Scheme Variable} rsync-service-type
14402 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
14403 The value for this service type is a
14404 @command{rsync-configuration} record as in this example:
14407 (service rsync-service-type)
14410 See below for details about @code{rsync-configuration}.
14413 @deftp {Data Type} rsync-configuration
14414 Data type representing the configuration for @code{rsync-service}.
14417 @item @code{package} (default: @var{rsync})
14418 @code{rsync} package to use.
14420 @item @code{port-number} (default: @code{873})
14421 TCP port on which @command{rsync} listens for incoming connections. If port
14422 is less than @code{1024} @command{rsync} needs to be started as the
14423 @code{root} user and group.
14425 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
14426 Name of the file where @command{rsync} writes its PID.
14428 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
14429 Name of the file where @command{rsync} writes its lock file.
14431 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
14432 Name of the file where @command{rsync} writes its log file.
14434 @item @code{use-chroot?} (default: @var{#t})
14435 Whether to use chroot for @command{rsync} shared directory.
14437 @item @code{share-path} (default: @file{/srv/rsync})
14438 Location of the @command{rsync} shared directory.
14440 @item @code{share-comment} (default: @code{"Rsync share"})
14441 Comment of the @command{rsync} shared directory.
14443 @item @code{read-only?} (default: @var{#f})
14444 Read-write permissions to shared directory.
14446 @item @code{timeout} (default: @code{300})
14447 I/O timeout in seconds.
14449 @item @code{user} (default: @var{"root"})
14450 Owner of the @code{rsync} process.
14452 @item @code{group} (default: @var{"root"})
14453 Group of the @code{rsync} process.
14455 @item @code{uid} (default: @var{"rsyncd"})
14456 User name or user ID that file transfers to and from that module should take
14457 place as when the daemon was run as @code{root}.
14459 @item @code{gid} (default: @var{"rsyncd"})
14460 Group name or group ID that will be used when accessing the module.
14465 Furthermore, @code{(gnu services ssh)} provides the following services.
14469 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
14470 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
14471 [#:allow-empty-passwords? #f] [#:root-login? #f] @
14472 [#:syslog-output? #t] [#:x11-forwarding? #t] @
14473 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
14474 [#:public-key-authentication? #t] [#:initialize? #t]
14475 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
14476 @var{host-key} must designate a file containing the host key, and readable
14479 When @var{daemonic?} is true, @command{lshd} will detach from the
14480 controlling terminal and log its output to syslogd, unless one sets
14481 @var{syslog-output?} to false. Obviously, it also makes lsh-service
14482 depend on existence of syslogd service. When @var{pid-file?} is true,
14483 @command{lshd} writes its PID to the file called @var{pid-file}.
14485 When @var{initialize?} is true, automatically create the seed and host key
14486 upon service activation if they do not exist yet. This may take long and
14487 require interaction.
14489 When @var{initialize?} is false, it is up to the user to initialize the
14490 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
14491 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
14492 basics,,, lsh, LSH Manual}).
14494 When @var{interfaces} is empty, lshd listens for connections on all the
14495 network interfaces; otherwise, @var{interfaces} must be a list of host names
14498 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
14499 passwords, and @var{root-login?} specifies whether to accept log-ins as
14502 The other options should be self-descriptive.
14507 @deffn {Scheme Variable} openssh-service-type
14508 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
14509 shell daemon, @command{sshd}. Its value must be an
14510 @code{openssh-configuration} record as in this example:
14513 (service openssh-service-type
14514 (openssh-configuration
14515 (x11-forwarding? #t)
14516 (permit-root-login 'without-password)
14518 `(("alice" ,(local-file "alice.pub"))
14519 ("bob" ,(local-file "bob.pub"))))))
14522 See below for details about @code{openssh-configuration}.
14524 This service can be extended with extra authorized keys, as in this
14528 (service-extension openssh-service-type
14529 (const `(("charlie"
14530 ,(local-file "charlie.pub")))))
14534 @deftp {Data Type} openssh-configuration
14535 This is the configuration record for OpenSSH's @command{sshd}.
14538 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
14539 Name of the file where @command{sshd} writes its PID.
14541 @item @code{port-number} (default: @code{22})
14542 TCP port on which @command{sshd} listens for incoming connections.
14544 @item @code{permit-root-login} (default: @code{#f})
14545 This field determines whether and when to allow logins as root. If
14546 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
14547 If it's the symbol @code{'without-password}, then root logins are
14548 permitted but not with password-based authentication.
14550 @item @code{allow-empty-passwords?} (default: @code{#f})
14551 When true, users with empty passwords may log in. When false, they may
14554 @item @code{password-authentication?} (default: @code{#t})
14555 When true, users may log in with their password. When false, they have
14556 other authentication methods.
14558 @item @code{public-key-authentication?} (default: @code{#t})
14559 When true, users may log in using public key authentication. When
14560 false, users have to use other authentication method.
14562 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
14563 This is used only by protocol version 2.
14565 @item @code{x11-forwarding?} (default: @code{#f})
14566 When true, forwarding of X11 graphical client connections is
14567 enabled---in other words, @command{ssh} options @option{-X} and
14568 @option{-Y} will work.
14570 @item @code{allow-agent-forwarding?} (default: @code{#t})
14571 Whether to allow agent forwarding.
14573 @item @code{allow-tcp-forwarding?} (default: @code{#t})
14574 Whether to allow TCP forwarding.
14576 @item @code{gateway-ports?} (default: @code{#f})
14577 Whether to allow gateway ports.
14579 @item @code{challenge-response-authentication?} (default: @code{#f})
14580 Specifies whether challenge response authentication is allowed (e.g.@: via
14583 @item @code{use-pam?} (default: @code{#t})
14584 Enables the Pluggable Authentication Module interface. If set to
14585 @code{#t}, this will enable PAM authentication using
14586 @code{challenge-response-authentication?} and
14587 @code{password-authentication?}, in addition to PAM account and session
14588 module processing for all authentication types.
14590 Because PAM challenge response authentication usually serves an
14591 equivalent role to password authentication, you should disable either
14592 @code{challenge-response-authentication?} or
14593 @code{password-authentication?}.
14595 @item @code{print-last-log?} (default: @code{#t})
14596 Specifies whether @command{sshd} should print the date and time of the
14597 last user login when a user logs in interactively.
14599 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
14600 Configures external subsystems (e.g.@: file transfer daemon).
14602 This is a list of two-element lists, each of which containing the
14603 subsystem name and a command (with optional arguments) to execute upon
14606 The command @command{internal-sftp} implements an in-process SFTP
14607 server. Alternatively, one can specify the @command{sftp-server} command:
14609 (service openssh-service-type
14610 (openssh-configuration
14612 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
14615 @item @code{accepted-environment} (default: @code{'()})
14616 List of strings describing which environment variables may be exported.
14618 Each string gets on its own line. See the @code{AcceptEnv} option in
14619 @code{man sshd_config}.
14621 This example allows ssh-clients to export the @env{COLORTERM} variable.
14622 It is set by terminal emulators, which support colors. You can use it in
14623 your shell's resource file to enable colors for the prompt and commands
14624 if this variable is set.
14627 (service openssh-service-type
14628 (openssh-configuration
14629 (accepted-environment '("COLORTERM"))))
14632 @item @code{authorized-keys} (default: @code{'()})
14633 @cindex authorized keys, SSH
14634 @cindex SSH authorized keys
14635 This is the list of authorized keys. Each element of the list is a user
14636 name followed by one or more file-like objects that represent SSH public
14640 (openssh-configuration
14642 `(("rekado" ,(local-file "rekado.pub"))
14643 ("chris" ,(local-file "chris.pub"))
14644 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
14648 registers the specified public keys for user accounts @code{rekado},
14649 @code{chris}, and @code{root}.
14651 Additional authorized keys can be specified @i{via}
14652 @code{service-extension}.
14654 Note that this does @emph{not} interfere with the use of
14655 @file{~/.ssh/authorized_keys}.
14657 @item @code{log-level} (default: @code{'info})
14658 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
14659 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
14660 page for @file{sshd_config} for the full list of level names.
14662 @item @code{extra-content} (default: @code{""})
14663 This field can be used to append arbitrary text to the configuration file. It
14664 is especially useful for elaborate configurations that cannot be expressed
14665 otherwise. This configuration, for example, would generally disable root
14666 logins, but permit them from one specific IP address:
14669 (openssh-configuration
14671 Match Address 192.168.0.1
14672 PermitRootLogin yes"))
14678 @deffn {Scheme Procedure} dropbear-service [@var{config}]
14679 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
14680 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
14683 For example, to specify a Dropbear service listening on port 1234, add
14684 this call to the operating system's @code{services} field:
14687 (dropbear-service (dropbear-configuration
14688 (port-number 1234)))
14692 @deftp {Data Type} dropbear-configuration
14693 This data type represents the configuration of a Dropbear SSH daemon.
14696 @item @code{dropbear} (default: @var{dropbear})
14697 The Dropbear package to use.
14699 @item @code{port-number} (default: 22)
14700 The TCP port where the daemon waits for incoming connections.
14702 @item @code{syslog-output?} (default: @code{#t})
14703 Whether to enable syslog output.
14705 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
14706 File name of the daemon's PID file.
14708 @item @code{root-login?} (default: @code{#f})
14709 Whether to allow @code{root} logins.
14711 @item @code{allow-empty-passwords?} (default: @code{#f})
14712 Whether to allow empty passwords.
14714 @item @code{password-authentication?} (default: @code{#t})
14715 Whether to enable password-based authentication.
14720 @deffn {Scheme Variable} autossh-service-type
14721 This is the type for the @uref{https://www.harding.motd.ca/autossh,
14722 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
14723 restarting it as necessary should it die or stop passing traffic.
14724 AutoSSH can be run manually from the command-line by passing arguments
14725 to the binary @command{autossh} from the package @code{autossh}, but it
14726 can also be run as a Guix service. This latter use case is documented
14729 AutoSSH can be used to forward local traffic to a remote machine using
14730 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
14733 For example, to specify a service running autossh as the user
14734 @code{pino} and forwarding all local connections to port @code{8081} to
14735 @code{remote:8081} using an SSH tunnel, add this call to the operating
14736 system's @code{services} field:
14739 (service autossh-service-type
14740 (autossh-configuration
14742 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
14746 @deftp {Data Type} autossh-configuration
14747 This data type represents the configuration of an AutoSSH service.
14751 @item @code{user} (default @code{"autossh"})
14752 The user as which the AutoSSH service is to be run.
14753 This assumes that the specified user exists.
14755 @item @code{poll} (default @code{600})
14756 Specifies the connection poll time in seconds.
14758 @item @code{first-poll} (default @code{#f})
14759 Specifies how many seconds AutoSSH waits before the first connection
14760 test. After this first test, polling is resumed at the pace defined in
14761 @code{poll}. When set to @code{#f}, the first poll is not treated
14762 specially and will also use the connection poll specified in
14765 @item @code{gate-time} (default @code{30})
14766 Specifies how many seconds an SSH connection must be active before it is
14767 considered successful.
14769 @item @code{log-level} (default @code{1})
14770 The log level, corresponding to the levels used by syslog---so @code{0}
14771 is the most silent while @code{7} is the chattiest.
14773 @item @code{max-start} (default @code{#f})
14774 The maximum number of times SSH may be (re)started before AutoSSH exits.
14775 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
14777 @item @code{message} (default @code{""})
14778 The message to append to the echo message sent when testing connections.
14780 @item @code{port} (default @code{"0"})
14781 The ports used for monitoring the connection. When set to @code{"0"},
14782 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
14783 a positive integer, ports @var{n} and @var{n}+1 are used for
14784 monitoring the connection, such that port @var{n} is the base
14785 monitoring port and @code{n+1} is the echo port. When set to
14786 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
14787 integers, the ports @var{n} and @var{n}+1 are used for monitoring the
14788 connection, such that port @var{n} is the base monitoring port and
14789 @var{m} is the echo port.
14791 @item @code{ssh-options} (default @code{'()})
14792 The list of command-line arguments to pass to @command{ssh} when it is
14793 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
14794 may cause undefined behaviour.
14799 @defvr {Scheme Variable} %facebook-host-aliases
14800 This variable contains a string for use in @file{/etc/hosts}
14801 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
14802 line contains a entry that maps a known server name of the Facebook
14803 on-line service---e.g., @code{www.facebook.com}---to the local
14804 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
14806 This variable is typically used in the @code{hosts-file} field of an
14807 @code{operating-system} declaration (@pxref{operating-system Reference,
14808 @file{/etc/hosts}}):
14811 (use-modules (gnu) (guix))
14814 (host-name "mymachine")
14817 ;; Create a /etc/hosts file with aliases for "localhost"
14818 ;; and "mymachine", as well as for Facebook servers.
14819 (plain-file "hosts"
14820 (string-append (local-host-aliases host-name)
14821 %facebook-host-aliases))))
14824 This mechanism can prevent programs running locally, such as Web
14825 browsers, from accessing Facebook.
14828 The @code{(gnu services avahi)} provides the following definition.
14830 @defvr {Scheme Variable} avahi-service-type
14831 This is the service that runs @command{avahi-daemon}, a system-wide
14832 mDNS/DNS-SD responder that allows for service discovery and
14833 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
14834 Its value must be a @code{zero-configuration} record---see below.
14836 This service extends the name service cache daemon (nscd) so that it can
14837 resolve @code{.local} host names using
14838 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
14839 Service Switch}, for information on host name resolution.
14841 Additionally, add the @var{avahi} package to the system profile so that
14842 commands such as @command{avahi-browse} are directly usable.
14845 @deftp {Data Type} avahi-configuration
14846 Data type representation the configuration for Avahi.
14850 @item @code{host-name} (default: @code{#f})
14851 If different from @code{#f}, use that as the host name to
14852 publish for this machine; otherwise, use the machine's actual host name.
14854 @item @code{publish?} (default: @code{#t})
14855 When true, allow host names and services to be published (broadcast) over the
14858 @item @code{publish-workstation?} (default: @code{#t})
14859 When true, @command{avahi-daemon} publishes the machine's host name and IP
14860 address via mDNS on the local network. To view the host names published on
14861 your local network, you can run:
14864 avahi-browse _workstation._tcp
14867 @item @code{wide-area?} (default: @code{#f})
14868 When true, DNS-SD over unicast DNS is enabled.
14870 @item @code{ipv4?} (default: @code{#t})
14871 @itemx @code{ipv6?} (default: @code{#t})
14872 These fields determine whether to use IPv4/IPv6 sockets.
14874 @item @code{domains-to-browse} (default: @code{'()})
14875 This is a list of domains to browse.
14879 @deffn {Scheme Variable} openvswitch-service-type
14880 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
14881 service, whose value should be an @code{openvswitch-configuration}
14885 @deftp {Data Type} openvswitch-configuration
14886 Data type representing the configuration of Open vSwitch, a multilayer
14887 virtual switch which is designed to enable massive network automation
14888 through programmatic extension.
14891 @item @code{package} (default: @var{openvswitch})
14892 Package object of the Open vSwitch.
14897 @defvr {Scheme Variable} pagekite-service-type
14898 This is the service type for the @uref{https://pagekite.net, PageKite} service,
14899 a tunneling solution for making localhost servers publicly visible, even from
14900 behind restrictive firewalls or NAT without forwarded ports. The value for
14901 this service type is a @code{pagekite-configuration} record.
14903 Here's an example exposing the local HTTP and SSH daemons:
14906 (service pagekite-service-type
14907 (pagekite-configuration
14908 (kites '("http:@@kitename:localhost:80:@@kitesecret"
14909 "raw/22:@@kitename:localhost:22:@@kitesecret"))
14910 (extra-file "/etc/pagekite.rc")))
14914 @deftp {Data Type} pagekite-configuration
14915 Data type representing the configuration of PageKite.
14918 @item @code{package} (default: @var{pagekite})
14919 Package object of PageKite.
14921 @item @code{kitename} (default: @code{#f})
14922 PageKite name for authenticating to the frontend server.
14924 @item @code{kitesecret} (default: @code{#f})
14925 Shared secret for authenticating to the frontend server. You should probably
14926 put this inside @code{extra-file} instead.
14928 @item @code{frontend} (default: @code{#f})
14929 Connect to the named PageKite frontend server instead of the
14930 @uref{https://pagekite.net,,pagekite.net} service.
14932 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
14933 List of service kites to use. Exposes HTTP on port 80 by default. The format
14934 is @code{proto:kitename:host:port:secret}.
14936 @item @code{extra-file} (default: @code{#f})
14937 Extra configuration file to read, which you are expected to create manually.
14938 Use this to add additional options and manage shared secrets out-of-band.
14944 @subsection X Window
14947 @cindex X Window System
14948 @cindex login manager
14949 Support for the X Window graphical display system---specifically
14950 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
14951 there is no @code{xorg-service} procedure. Instead, the X server is
14952 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
14955 @cindex GNOME, login manager
14956 GDM of course allows users to log in into window managers and desktop
14957 environments other than GNOME; for those using GNOME, GDM is required for
14958 features such as automatic screen locking.
14960 @cindex window manager
14961 To use X11, you must install at least one @dfn{window manager}---for
14962 example the @code{windowmaker} or @code{openbox} packages---preferably
14963 by adding it to the @code{packages} field of your operating system
14964 definition (@pxref{operating-system Reference, system-wide packages}).
14966 @defvr {Scheme Variable} gdm-service-type
14967 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
14968 Desktop Manager} (GDM), a program that manages graphical display servers and
14969 handles graphical user logins. Its value must be a @code{gdm-configuration}
14972 @cindex session types (X11)
14973 @cindex X11 session types
14974 GDM looks for @dfn{session types} described by the @file{.desktop} files in
14975 @file{/run/current-system/profile/share/xsessions} and allows users to choose
14976 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
14977 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
14978 set of packages automatically makes them available at the log-in screen.
14980 In addition, @file{~/.xsession} files are honored. When available,
14981 @file{~/.xsession} must be an executable that starts a window manager
14982 and/or other X clients.
14985 @deftp {Data Type} gdm-configuration
14987 @item @code{auto-login?} (default: @code{#f})
14988 @itemx @code{default-user} (default: @code{#f})
14989 When @code{auto-login?} is false, GDM presents a log-in screen.
14991 When @code{auto-login?} is true, GDM logs in directly as
14992 @code{default-user}.
14994 @item @code{debug?} (default: @code{#f})
14995 When true, GDM writes debug messages to its log.
14997 @item @code{gnome-shell-assets} (default: ...)
14998 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
15000 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
15001 Configuration of the Xorg graphical server.
15003 @item @code{xsession} (default: @code{(xinitrc)})
15004 Script to run before starting a X session.
15006 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
15007 File name of the @code{dbus-daemon} executable.
15009 @item @code{gdm} (default: @code{gdm})
15010 The GDM package to use.
15014 @defvr {Scheme Variable} slim-service-type
15015 This is the type for the SLiM graphical login manager for X11.
15017 Like GDM, SLiM looks for session types described by @file{.desktop} files and
15018 allows users to choose a session from the log-in screen using @kbd{F1}. It
15019 also honors @file{~/.xsession} files.
15021 Unlike GDM, SLiM does not spawn the user session on a different VT after
15022 logging in, which means that you can only start one graphical session. If you
15023 want to be able to run multiple graphical sessions at the same time you have
15024 to add multiple SLiM services to your system services. The following example
15025 shows how to replace the default GDM service with two SLiM services on tty7
15029 (use-modules (gnu services)
15030 (gnu services desktop)
15031 (gnu services xorg)
15032 (srfi srfi-1)) ;for 'remove'
15036 (services (cons* (service slim-service-type (slim-configuration
15039 (service slim-service-type (slim-configuration
15042 (remove (lambda (service)
15043 (eq? (service-kind service) gdm-service-type))
15044 %desktop-services))))
15049 @deftp {Data Type} slim-configuration
15050 Data type representing the configuration of @code{slim-service-type}.
15053 @item @code{allow-empty-passwords?} (default: @code{#t})
15054 Whether to allow logins with empty passwords.
15056 @item @code{auto-login?} (default: @code{#f})
15057 @itemx @code{default-user} (default: @code{""})
15058 When @code{auto-login?} is false, SLiM presents a log-in screen.
15060 When @code{auto-login?} is true, SLiM logs in directly as
15061 @code{default-user}.
15063 @item @code{theme} (default: @code{%default-slim-theme})
15064 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
15065 The graphical theme to use and its name.
15067 @item @code{auto-login-session} (default: @code{#f})
15068 If true, this must be the name of the executable to start as the default
15069 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
15071 If false, a session described by one of the available @file{.desktop}
15072 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
15076 You must install at least one window manager in the system profile or in
15077 your user profile. Failing to do that, if @code{auto-login-session} is
15078 false, you will be unable to log in.
15081 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
15082 Configuration of the Xorg graphical server.
15084 @item @code{display} (default @code{":0"})
15085 The display on which to start the Xorg graphical server.
15087 @item @code{vt} (default @code{"vt7"})
15088 The VT on which to start the Xorg graphical server.
15090 @item @code{xauth} (default: @code{xauth})
15091 The XAuth package to use.
15093 @item @code{shepherd} (default: @code{shepherd})
15094 The Shepherd package used when invoking @command{halt} and
15097 @item @code{sessreg} (default: @code{sessreg})
15098 The sessreg package used in order to register the session.
15100 @item @code{slim} (default: @code{slim})
15101 The SLiM package to use.
15105 @defvr {Scheme Variable} %default-theme
15106 @defvrx {Scheme Variable} %default-theme-name
15107 The default SLiM theme and its name.
15111 @deftp {Data Type} sddm-configuration
15112 This is the data type representing the SDDM service configuration.
15115 @item @code{display-server} (default: "x11")
15116 Select display server to use for the greeter. Valid values are
15117 @samp{"x11"} or @samp{"wayland"}.
15119 @item @code{numlock} (default: "on")
15120 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
15122 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
15123 Command to run when halting.
15125 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
15126 Command to run when rebooting.
15128 @item @code{theme} (default "maldives")
15129 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
15130 @samp{"maldives"} or @samp{"maya"}.
15132 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
15133 Directory to look for themes.
15135 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
15136 Directory to look for faces.
15138 @item @code{default-path} (default "/run/current-system/profile/bin")
15139 Default PATH to use.
15141 @item @code{minimum-uid} (default: 1000)
15142 Minimum UID displayed in SDDM and allowed for log-in.
15144 @item @code{maximum-uid} (default: 2000)
15145 Maximum UID to display in SDDM.
15147 @item @code{remember-last-user?} (default #t)
15148 Remember last user.
15150 @item @code{remember-last-session?} (default #t)
15151 Remember last session.
15153 @item @code{hide-users} (default "")
15154 Usernames to hide from SDDM greeter.
15156 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
15157 Users with shells listed will be hidden from the SDDM greeter.
15159 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
15160 Script to run before starting a wayland session.
15162 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
15163 Directory to look for desktop files starting wayland sessions.
15165 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
15166 Configuration of the Xorg graphical server.
15168 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
15171 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
15174 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
15175 Script to run after starting xorg-server.
15177 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
15178 Script to run before stopping xorg-server.
15180 @item @code{xsession-command} (default: @code{xinitrc})
15181 Script to run before starting a X session.
15183 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
15184 Directory to look for desktop files starting X sessions.
15186 @item @code{minimum-vt} (default: 7)
15189 @item @code{auto-login-user} (default "")
15190 User to use for auto-login.
15192 @item @code{auto-login-session} (default "")
15193 Desktop file to use for auto-login.
15195 @item @code{relogin?} (default #f)
15196 Relogin after logout.
15201 @cindex login manager
15203 @defvr {Scheme Variable} sddm-service-type
15204 This is the type of the service to run the
15205 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
15206 must be a @code{sddm-configuration} record (see below).
15208 Here's an example use:
15211 (service sddm-service-type
15212 (sddm-configuration
15213 (auto-login-user "alice")
15214 (auto-login-session "xfce.desktop")))
15218 @deftp {Data Type} sddm-configuration
15219 This data type represents the configuration of the SDDM login manager.
15220 The available fields are:
15223 @item @code{sddm} (default: @code{sddm})
15224 The SDDM package to use.
15226 @item @code{display-server} (default: @code{"x11"})
15227 This must be either @code{"x11"} or @code{"wayland"}.
15229 @c FIXME: Add more fields.
15231 @item @code{auto-login-user} (default: @code{""})
15232 If non-empty, this is the user account under which to log in
15235 @item @code{auto-login-session} (default: @code{""})
15236 If non-empty, this is the @file{.desktop} file name to use as the
15237 auto-login session.
15241 @cindex Xorg, configuration
15242 @deftp {Data Type} xorg-configuration
15243 This data type represents the configuration of the Xorg graphical display
15244 server. Note that there is not Xorg service; instead, the X server is started
15245 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
15246 of these display managers aggregates an @code{xorg-configuration} record.
15249 @item @code{modules} (default: @code{%default-xorg-modules})
15250 This is a list of @dfn{module packages} loaded by the Xorg
15251 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
15253 @item @code{fonts} (default: @code{%default-xorg-fonts})
15254 This is a list of font directories to add to the server's @dfn{font path}.
15256 @item @code{drivers} (default: @code{'()})
15257 This must be either the empty list, in which case Xorg chooses a graphics
15258 driver automatically, or a list of driver names that will be tried in this
15259 order---e.g., @code{("modesetting" "vesa")}.
15261 @item @code{resolutions} (default: @code{'()})
15262 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
15263 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
15266 @cindex keyboard layout, for Xorg
15267 @cindex keymap, for Xorg
15268 @item @code{keyboard-layout} (default: @code{#f})
15269 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
15270 English (``qwerty'') for a 105-key PC keyboard.
15272 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
15273 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
15274 information on how to specify the keyboard layout.
15276 @item @code{extra-config} (default: @code{'()})
15277 This is a list of strings or objects appended to the configuration file. It
15278 is used to pass extra text to be added verbatim to the configuration file.
15280 @item @code{server} (default: @code{xorg-server})
15281 This is the package providing the Xorg server.
15283 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
15284 This is the list of command-line arguments to pass to the X server. The
15285 default is @code{-nolisten tcp}.
15289 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
15290 [@var{login-manager-service-type}]
15291 Tell the log-in manager (of type @var{login-manager-service-type}) to use
15292 @var{config}, an @code{<xorg-configuration>} record.
15294 Since the Xorg configuration is embedded in the log-in manager's
15295 configuration---e.g., @code{gdm-configuration}---this procedure provides a
15296 shorthand to set the Xorg configuration.
15299 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
15300 Return a @code{startx} script in which the modules, fonts, etc. specified
15301 in @var{config}, are available. The result should be used in place of
15304 Usually the X server is started by a login manager.
15308 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
15309 Add @var{package}, a package for a screen locker or screen saver whose
15310 command is @var{program}, to the set of setuid programs and add a PAM entry
15311 for it. For example:
15314 (screen-locker-service xlockmore "xlock")
15317 makes the good ol' XlockMore usable.
15321 @node Printing Services
15322 @subsection Printing Services
15324 @cindex printer support with CUPS
15325 The @code{(gnu services cups)} module provides a Guix service definition
15326 for the CUPS printing service. To add printer support to a Guix
15327 system, add a @code{cups-service} to the operating system definition:
15329 @deffn {Scheme Variable} cups-service-type
15330 The service type for the CUPS print server. Its value should be a valid
15331 CUPS configuration (see below). To use the default settings, simply
15334 (service cups-service-type)
15338 The CUPS configuration controls the basic things about your CUPS
15339 installation: what interfaces it listens on, what to do if a print job
15340 fails, how much logging to do, and so on. To actually add a printer,
15341 you have to visit the @url{http://localhost:631} URL, or use a tool such
15342 as GNOME's printer configuration services. By default, configuring a
15343 CUPS service will generate a self-signed certificate if needed, for
15344 secure connections to the print server.
15346 Suppose you want to enable the Web interface of CUPS and also add
15347 support for Epson printers @i{via} the @code{escpr} package and for HP
15348 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
15349 like this (you need to use the @code{(gnu packages cups)} module):
15352 (service cups-service-type
15353 (cups-configuration
15354 (web-interface? #t)
15356 (list cups-filters escpr hplip-minimal))))
15359 Note: If you wish to use the Qt5 based GUI which comes with the hplip
15360 package then it is suggested that you install the @code{hplip} package,
15361 either in your OS configuration file or as your user.
15363 The available configuration parameters follow. Each parameter
15364 definition is preceded by its type; for example, @samp{string-list foo}
15365 indicates that the @code{foo} parameter should be specified as a list of
15366 strings. There is also a way to specify the configuration as a string,
15367 if you have an old @code{cupsd.conf} file that you want to port over
15368 from some other system; see the end for more details.
15370 @c The following documentation was initially generated by
15371 @c (generate-documentation) in (gnu services cups). Manually maintained
15372 @c documentation is better, so we shouldn't hesitate to edit below as
15373 @c needed. However if the change you want to make to this documentation
15374 @c can be done in an automated way, it's probably easier to change
15375 @c (generate-documentation) than to make it below and have to deal with
15376 @c the churn as CUPS updates.
15379 Available @code{cups-configuration} fields are:
15381 @deftypevr {@code{cups-configuration} parameter} package cups
15385 @deftypevr {@code{cups-configuration} parameter} package-list extensions
15386 Drivers and other extensions to the CUPS package.
15389 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
15390 Configuration of where to write logs, what directories to use for print
15391 spools, and related privileged configuration parameters.
15393 Available @code{files-configuration} fields are:
15395 @deftypevr {@code{files-configuration} parameter} log-location access-log
15396 Defines the access log filename. Specifying a blank filename disables
15397 access log generation. The value @code{stderr} causes log entries to be
15398 sent to the standard error file when the scheduler is running in the
15399 foreground, or to the system log daemon when run in the background. The
15400 value @code{syslog} causes log entries to be sent to the system log
15401 daemon. The server name may be included in filenames using the string
15402 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
15404 Defaults to @samp{"/var/log/cups/access_log"}.
15407 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
15408 Where CUPS should cache data.
15410 Defaults to @samp{"/var/cache/cups"}.
15413 @deftypevr {@code{files-configuration} parameter} string config-file-perm
15414 Specifies the permissions for all configuration files that the scheduler
15417 Note that the permissions for the printers.conf file are currently
15418 masked to only allow access from the scheduler user (typically root).
15419 This is done because printer device URIs sometimes contain sensitive
15420 authentication information that should not be generally known on the
15421 system. There is no way to disable this security feature.
15423 Defaults to @samp{"0640"}.
15426 @deftypevr {@code{files-configuration} parameter} log-location error-log
15427 Defines the error log filename. Specifying a blank filename disables
15428 error log generation. The value @code{stderr} causes log entries to be
15429 sent to the standard error file when the scheduler is running in the
15430 foreground, or to the system log daemon when run in the background. The
15431 value @code{syslog} causes log entries to be sent to the system log
15432 daemon. The server name may be included in filenames using the string
15433 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
15435 Defaults to @samp{"/var/log/cups/error_log"}.
15438 @deftypevr {@code{files-configuration} parameter} string fatal-errors
15439 Specifies which errors are fatal, causing the scheduler to exit. The
15444 No errors are fatal.
15447 All of the errors below are fatal.
15450 Browsing initialization errors are fatal, for example failed connections
15451 to the DNS-SD daemon.
15454 Configuration file syntax errors are fatal.
15457 Listen or Port errors are fatal, except for IPv6 failures on the
15458 loopback or @code{any} addresses.
15461 Log file creation or write errors are fatal.
15464 Bad startup file permissions are fatal, for example shared TLS
15465 certificate and key files with world-read permissions.
15468 Defaults to @samp{"all -browse"}.
15471 @deftypevr {@code{files-configuration} parameter} boolean file-device?
15472 Specifies whether the file pseudo-device can be used for new printer
15473 queues. The URI @uref{file:///dev/null} is always allowed.
15475 Defaults to @samp{#f}.
15478 @deftypevr {@code{files-configuration} parameter} string group
15479 Specifies the group name or ID that will be used when executing external
15482 Defaults to @samp{"lp"}.
15485 @deftypevr {@code{files-configuration} parameter} string log-file-perm
15486 Specifies the permissions for all log files that the scheduler writes.
15488 Defaults to @samp{"0644"}.
15491 @deftypevr {@code{files-configuration} parameter} log-location page-log
15492 Defines the page log filename. Specifying a blank filename disables
15493 page log generation. The value @code{stderr} causes log entries to be
15494 sent to the standard error file when the scheduler is running in the
15495 foreground, or to the system log daemon when run in the background. The
15496 value @code{syslog} causes log entries to be sent to the system log
15497 daemon. The server name may be included in filenames using the string
15498 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
15500 Defaults to @samp{"/var/log/cups/page_log"}.
15503 @deftypevr {@code{files-configuration} parameter} string remote-root
15504 Specifies the username that is associated with unauthenticated accesses
15505 by clients claiming to be the root user. The default is @code{remroot}.
15507 Defaults to @samp{"remroot"}.
15510 @deftypevr {@code{files-configuration} parameter} file-name request-root
15511 Specifies the directory that contains print jobs and other HTTP request
15514 Defaults to @samp{"/var/spool/cups"}.
15517 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
15518 Specifies the level of security sandboxing that is applied to print
15519 filters, backends, and other child processes of the scheduler; either
15520 @code{relaxed} or @code{strict}. This directive is currently only
15521 used/supported on macOS.
15523 Defaults to @samp{strict}.
15526 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
15527 Specifies the location of TLS certificates and private keys. CUPS will
15528 look for public and private keys in this directory: @file{.crt} files
15529 for PEM-encoded certificates and corresponding @file{.key} files for
15530 PEM-encoded private keys.
15532 Defaults to @samp{"/etc/cups/ssl"}.
15535 @deftypevr {@code{files-configuration} parameter} file-name server-root
15536 Specifies the directory containing the server configuration files.
15538 Defaults to @samp{"/etc/cups"}.
15541 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
15542 Specifies whether the scheduler calls fsync(2) after writing
15543 configuration or state files.
15545 Defaults to @samp{#f}.
15548 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
15549 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
15552 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
15553 Specifies the directory where temporary files are stored.
15555 Defaults to @samp{"/var/spool/cups/tmp"}.
15558 @deftypevr {@code{files-configuration} parameter} string user
15559 Specifies the user name or ID that is used when running external
15562 Defaults to @samp{"lp"}.
15565 @deftypevr {@code{files-configuration} parameter} string set-env
15566 Set the specified environment variable to be passed to child processes.
15568 Defaults to @samp{"variable value"}.
15572 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
15573 Specifies the logging level for the AccessLog file. The @code{config}
15574 level logs when printers and classes are added, deleted, or modified and
15575 when configuration files are accessed or updated. The @code{actions}
15576 level logs when print jobs are submitted, held, released, modified, or
15577 canceled, and any of the conditions for @code{config}. The @code{all}
15578 level logs all requests.
15580 Defaults to @samp{actions}.
15583 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
15584 Specifies whether to purge job history data automatically when it is no
15585 longer required for quotas.
15587 Defaults to @samp{#f}.
15590 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
15591 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
15592 For example, @samp{"_cups" "_print"} will tell network clients that both
15593 CUPS sharing and IPP Everywhere are supported.
15595 Defaults to @samp{"_cups"}.
15598 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
15599 Specifies which protocols to use for local printer sharing.
15601 Defaults to @samp{dnssd}.
15604 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
15605 Specifies whether the CUPS web interface is advertised.
15607 Defaults to @samp{#f}.
15610 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
15611 Specifies whether shared printers are advertised.
15613 Defaults to @samp{#f}.
15616 @deftypevr {@code{cups-configuration} parameter} string classification
15617 Specifies the security classification of the server. Any valid banner
15618 name can be used, including @samp{"classified"}, @samp{"confidential"},
15619 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
15620 banner can be omitted to disable secure printing functions.
15622 Defaults to @samp{""}.
15625 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
15626 Specifies whether users may override the classification (cover page) of
15627 individual print jobs using the @code{job-sheets} option.
15629 Defaults to @samp{#f}.
15632 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
15633 Specifies the default type of authentication to use.
15635 Defaults to @samp{Basic}.
15638 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
15639 Specifies whether encryption will be used for authenticated requests.
15641 Defaults to @samp{Required}.
15644 @deftypevr {@code{cups-configuration} parameter} string default-language
15645 Specifies the default language to use for text and web content.
15647 Defaults to @samp{"en"}.
15650 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
15651 Specifies the default paper size for new print queues. @samp{"Auto"}
15652 uses a locale-specific default, while @samp{"None"} specifies there is
15653 no default paper size. Specific size names are typically
15654 @samp{"Letter"} or @samp{"A4"}.
15656 Defaults to @samp{"Auto"}.
15659 @deftypevr {@code{cups-configuration} parameter} string default-policy
15660 Specifies the default access policy to use.
15662 Defaults to @samp{"default"}.
15665 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
15666 Specifies whether local printers are shared by default.
15668 Defaults to @samp{#t}.
15671 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
15672 Specifies the delay for updating of configuration and state files, in
15673 seconds. A value of 0 causes the update to happen as soon as possible,
15674 typically within a few milliseconds.
15676 Defaults to @samp{30}.
15679 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
15680 Specifies what to do when an error occurs. Possible values are
15681 @code{abort-job}, which will discard the failed print job;
15682 @code{retry-job}, which will retry the job at a later time;
15683 @code{retry-current-job}, which retries the failed job immediately; and
15684 @code{stop-printer}, which stops the printer.
15686 Defaults to @samp{stop-printer}.
15689 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
15690 Specifies the maximum cost of filters that are run concurrently, which
15691 can be used to minimize disk, memory, and CPU resource problems. A
15692 limit of 0 disables filter limiting. An average print to a
15693 non-PostScript printer needs a filter limit of about 200. A PostScript
15694 printer needs about half that (100). Setting the limit below these
15695 thresholds will effectively limit the scheduler to printing a single job
15698 Defaults to @samp{0}.
15701 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
15702 Specifies the scheduling priority of filters that are run to print a
15703 job. The nice value ranges from 0, the highest priority, to 19, the
15706 Defaults to @samp{0}.
15709 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
15710 Specifies whether to do reverse lookups on connecting clients. The
15711 @code{double} setting causes @code{cupsd} to verify that the hostname
15712 resolved from the address matches one of the addresses returned for that
15713 hostname. Double lookups also prevent clients with unregistered
15714 addresses from connecting to your server. Only set this option to
15715 @code{#t} or @code{double} if absolutely required.
15717 Defaults to @samp{#f}.
15720 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
15721 Specifies the number of seconds to wait before killing the filters and
15722 backend associated with a canceled or held job.
15724 Defaults to @samp{30}.
15727 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
15728 Specifies the interval between retries of jobs in seconds. This is
15729 typically used for fax queues but can also be used with normal print
15730 queues whose error policy is @code{retry-job} or
15731 @code{retry-current-job}.
15733 Defaults to @samp{30}.
15736 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
15737 Specifies the number of retries that are done for jobs. This is
15738 typically used for fax queues but can also be used with normal print
15739 queues whose error policy is @code{retry-job} or
15740 @code{retry-current-job}.
15742 Defaults to @samp{5}.
15745 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
15746 Specifies whether to support HTTP keep-alive connections.
15748 Defaults to @samp{#t}.
15751 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
15752 Specifies how long an idle client connection remains open, in seconds.
15754 Defaults to @samp{30}.
15757 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
15758 Specifies the maximum size of print files, IPP requests, and HTML form
15759 data. A limit of 0 disables the limit check.
15761 Defaults to @samp{0}.
15764 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
15765 Listens on the specified interfaces for connections. Valid values are
15766 of the form @var{address}:@var{port}, where @var{address} is either an
15767 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
15768 indicate all addresses. Values can also be file names of local UNIX
15769 domain sockets. The Listen directive is similar to the Port directive
15770 but allows you to restrict access to specific interfaces or networks.
15773 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
15774 Specifies the number of pending connections that will be allowed. This
15775 normally only affects very busy servers that have reached the MaxClients
15776 limit, but can also be triggered by large numbers of simultaneous
15777 connections. When the limit is reached, the operating system will
15778 refuse additional connections until the scheduler can accept the pending
15781 Defaults to @samp{128}.
15784 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
15785 Specifies a set of additional access controls.
15787 Available @code{location-access-controls} fields are:
15789 @deftypevr {@code{location-access-controls} parameter} file-name path
15790 Specifies the URI path to which the access control applies.
15793 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
15794 Access controls for all access to this path, in the same format as the
15795 @code{access-controls} of @code{operation-access-control}.
15797 Defaults to @samp{()}.
15800 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
15801 Access controls for method-specific access to this path.
15803 Defaults to @samp{()}.
15805 Available @code{method-access-controls} fields are:
15807 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
15808 If @code{#t}, apply access controls to all methods except the listed
15809 methods. Otherwise apply to only the listed methods.
15811 Defaults to @samp{#f}.
15814 @deftypevr {@code{method-access-controls} parameter} method-list methods
15815 Methods to which this access control applies.
15817 Defaults to @samp{()}.
15820 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
15821 Access control directives, as a list of strings. Each string should be
15822 one directive, such as @samp{"Order allow,deny"}.
15824 Defaults to @samp{()}.
15829 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
15830 Specifies the number of debugging messages that are retained for logging
15831 if an error occurs in a print job. Debug messages are logged regardless
15832 of the LogLevel setting.
15834 Defaults to @samp{100}.
15837 @deftypevr {@code{cups-configuration} parameter} log-level log-level
15838 Specifies the level of logging for the ErrorLog file. The value
15839 @code{none} stops all logging while @code{debug2} logs everything.
15841 Defaults to @samp{info}.
15844 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
15845 Specifies the format of the date and time in the log files. The value
15846 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
15848 Defaults to @samp{standard}.
15851 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
15852 Specifies the maximum number of simultaneous clients that are allowed by
15855 Defaults to @samp{100}.
15858 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
15859 Specifies the maximum number of simultaneous clients that are allowed
15860 from a single address.
15862 Defaults to @samp{100}.
15865 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
15866 Specifies the maximum number of copies that a user can print of each
15869 Defaults to @samp{9999}.
15872 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
15873 Specifies the maximum time a job may remain in the @code{indefinite}
15874 hold state before it is canceled. A value of 0 disables cancellation of
15877 Defaults to @samp{0}.
15880 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
15881 Specifies the maximum number of simultaneous jobs that are allowed. Set
15882 to 0 to allow an unlimited number of jobs.
15884 Defaults to @samp{500}.
15887 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
15888 Specifies the maximum number of simultaneous jobs that are allowed per
15889 printer. A value of 0 allows up to MaxJobs jobs per printer.
15891 Defaults to @samp{0}.
15894 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
15895 Specifies the maximum number of simultaneous jobs that are allowed per
15896 user. A value of 0 allows up to MaxJobs jobs per user.
15898 Defaults to @samp{0}.
15901 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
15902 Specifies the maximum time a job may take to print before it is
15903 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
15905 Defaults to @samp{10800}.
15908 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
15909 Specifies the maximum size of the log files before they are rotated, in
15910 bytes. The value 0 disables log rotation.
15912 Defaults to @samp{1048576}.
15915 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
15916 Specifies the maximum amount of time to allow between files in a
15917 multiple file print job, in seconds.
15919 Defaults to @samp{300}.
15922 @deftypevr {@code{cups-configuration} parameter} string page-log-format
15923 Specifies the format of PageLog lines. Sequences beginning with percent
15924 (@samp{%}) characters are replaced with the corresponding information,
15925 while all other characters are copied literally. The following percent
15926 sequences are recognized:
15930 insert a single percent character
15933 insert the value of the specified IPP attribute
15936 insert the number of copies for the current page
15939 insert the current page number
15942 insert the current date and time in common log format
15948 insert the printer name
15951 insert the username
15954 A value of the empty string disables page logging. The string @code{%p
15955 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
15956 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
15959 Defaults to @samp{""}.
15962 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
15963 Passes the specified environment variable(s) to child processes; a list
15966 Defaults to @samp{()}.
15969 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
15970 Specifies named access control policies.
15972 Available @code{policy-configuration} fields are:
15974 @deftypevr {@code{policy-configuration} parameter} string name
15975 Name of the policy.
15978 @deftypevr {@code{policy-configuration} parameter} string job-private-access
15979 Specifies an access list for a job's private values. @code{@@ACL} maps
15980 to the printer's requesting-user-name-allowed or
15981 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15982 owner. @code{@@SYSTEM} maps to the groups listed for the
15983 @code{system-group} field of the @code{files-config} configuration,
15984 which is reified into the @code{cups-files.conf(5)} file. Other
15985 possible elements of the access list include specific user names, and
15986 @code{@@@var{group}} to indicate members of a specific group. The
15987 access list may also be simply @code{all} or @code{default}.
15989 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15992 @deftypevr {@code{policy-configuration} parameter} string job-private-values
15993 Specifies the list of job values to make private, or @code{all},
15994 @code{default}, or @code{none}.
15996 Defaults to @samp{"job-name job-originating-host-name
15997 job-originating-user-name phone"}.
16000 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
16001 Specifies an access list for a subscription's private values.
16002 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
16003 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
16004 owner. @code{@@SYSTEM} maps to the groups listed for the
16005 @code{system-group} field of the @code{files-config} configuration,
16006 which is reified into the @code{cups-files.conf(5)} file. Other
16007 possible elements of the access list include specific user names, and
16008 @code{@@@var{group}} to indicate members of a specific group. The
16009 access list may also be simply @code{all} or @code{default}.
16011 Defaults to @samp{"@@OWNER @@SYSTEM"}.
16014 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
16015 Specifies the list of job values to make private, or @code{all},
16016 @code{default}, or @code{none}.
16018 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
16019 notify-subscriber-user-name notify-user-data"}.
16022 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
16023 Access control by IPP operation.
16025 Defaults to @samp{()}.
16029 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
16030 Specifies whether job files (documents) are preserved after a job is
16031 printed. If a numeric value is specified, job files are preserved for
16032 the indicated number of seconds after printing. Otherwise a boolean
16033 value applies indefinitely.
16035 Defaults to @samp{86400}.
16038 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
16039 Specifies whether the job history is preserved after a job is printed.
16040 If a numeric value is specified, the job history is preserved for the
16041 indicated number of seconds after printing. If @code{#t}, the job
16042 history is preserved until the MaxJobs limit is reached.
16044 Defaults to @samp{#t}.
16047 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
16048 Specifies the amount of time to wait for job completion before
16049 restarting the scheduler.
16051 Defaults to @samp{30}.
16054 @deftypevr {@code{cups-configuration} parameter} string rip-cache
16055 Specifies the maximum amount of memory to use when converting documents
16056 into bitmaps for a printer.
16058 Defaults to @samp{"128m"}.
16061 @deftypevr {@code{cups-configuration} parameter} string server-admin
16062 Specifies the email address of the server administrator.
16064 Defaults to @samp{"root@@localhost.localdomain"}.
16067 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
16068 The ServerAlias directive is used for HTTP Host header validation when
16069 clients connect to the scheduler from external interfaces. Using the
16070 special name @code{*} can expose your system to known browser-based DNS
16071 rebinding attacks, even when accessing sites through a firewall. If the
16072 auto-discovery of alternate names does not work, we recommend listing
16073 each alternate name with a ServerAlias directive instead of using
16076 Defaults to @samp{*}.
16079 @deftypevr {@code{cups-configuration} parameter} string server-name
16080 Specifies the fully-qualified host name of the server.
16082 Defaults to @samp{"localhost"}.
16085 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
16086 Specifies what information is included in the Server header of HTTP
16087 responses. @code{None} disables the Server header. @code{ProductOnly}
16088 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
16089 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
16090 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
16091 the output of the @code{uname} command. @code{Full} reports @code{CUPS
16092 2.0.0 (@var{uname}) IPP/2.0}.
16094 Defaults to @samp{Minimal}.
16097 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
16098 Listens on the specified interfaces for encrypted connections. Valid
16099 values are of the form @var{address}:@var{port}, where @var{address} is
16100 either an IPv6 address enclosed in brackets, an IPv4 address, or
16101 @code{*} to indicate all addresses.
16103 Defaults to @samp{()}.
16106 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
16107 Sets encryption options. By default, CUPS only supports encryption
16108 using TLS v1.0 or higher using known secure cipher suites. Security is
16109 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
16110 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
16111 suites, which are required for some older clients. The @code{AllowSSL3} option
16112 enables SSL v3.0, which is required for some older clients that do not support
16113 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
16114 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
16115 protocol version to TLS v1.1.
16117 Defaults to @samp{()}.
16120 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
16121 Specifies whether the scheduler requires clients to strictly adhere to
16122 the IPP specifications.
16124 Defaults to @samp{#f}.
16127 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
16128 Specifies the HTTP request timeout, in seconds.
16130 Defaults to @samp{300}.
16134 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
16135 Specifies whether the web interface is enabled.
16137 Defaults to @samp{#f}.
16140 At this point you're probably thinking ``oh dear, Guix manual, I like
16141 you but you can stop already with the configuration options''. Indeed.
16142 However, one more point: it could be that you have an existing
16143 @code{cupsd.conf} that you want to use. In that case, you can pass an
16144 @code{opaque-cups-configuration} as the configuration of a
16145 @code{cups-service-type}.
16147 Available @code{opaque-cups-configuration} fields are:
16149 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
16153 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
16154 The contents of the @code{cupsd.conf}, as a string.
16157 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
16158 The contents of the @code{cups-files.conf} file, as a string.
16161 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
16162 strings of the same name, you could instantiate a CUPS service like
16166 (service cups-service-type
16167 (opaque-cups-configuration
16168 (cupsd.conf cupsd.conf)
16169 (cups-files.conf cups-files.conf)))
16173 @node Desktop Services
16174 @subsection Desktop Services
16176 The @code{(gnu services desktop)} module provides services that are
16177 usually useful in the context of a ``desktop'' setup---that is, on a
16178 machine running a graphical display server, possibly with graphical user
16179 interfaces, etc. It also defines services that provide specific desktop
16180 environments like GNOME, Xfce or MATE.
16182 To simplify things, the module defines a variable containing the set of
16183 services that users typically expect on a machine with a graphical
16184 environment and networking:
16186 @defvr {Scheme Variable} %desktop-services
16187 This is a list of services that builds upon @code{%base-services} and
16188 adds or adjusts services for a typical ``desktop'' setup.
16190 In particular, it adds a graphical login manager (@pxref{X Window,
16191 @code{gdm-service-type}}), screen lockers, a network management tool
16192 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
16193 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
16194 energy and color management services, the @code{elogind} login and seat
16195 manager, the Polkit privilege service, the GeoClue location service, the
16196 AccountsService daemon that allows authorized users change system passwords,
16197 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
16198 name service switch service configured to be able to use @code{nss-mdns}
16199 (@pxref{Name Service Switch, mDNS}).
16202 The @code{%desktop-services} variable can be used as the @code{services}
16203 field of an @code{operating-system} declaration (@pxref{operating-system
16204 Reference, @code{services}}).
16206 Additionally, the @code{gnome-desktop-service-type},
16207 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
16208 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
16209 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
16210 services like the backlight adjustment helpers and the power management
16211 utilities are added to the system, extending @code{polkit} and @code{dbus}
16212 appropriately, allowing GNOME to operate with elevated privileges on a
16213 limited number of special-purpose system interfaces. Additionally,
16214 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
16215 metapackage to the system profile. Likewise, adding the Xfce service
16216 not only adds the @code{xfce} metapackage to the system profile, but it
16217 also gives the Thunar file manager the ability to open a ``root-mode''
16218 file management window, if the user authenticates using the
16219 administrator's password via the standard polkit graphical interface.
16220 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
16221 appropriately, allowing MATE to operate with elevated privileges on a
16222 limited number of special-purpose system interfaces. Additionally,
16223 adding a service of type @code{mate-desktop-service-type} adds the MATE
16224 metapackage to the system profile. ``Adding Enlightenment'' means that
16225 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
16226 are set as setuid, allowing Enlightenment's screen locker and other
16227 functionality to work as expected.
16229 The desktop environments in Guix use the Xorg display server by
16230 default. If you'd like to use the newer display server protocol
16231 called Wayland, you need to use the @code{sddm-service} instead of
16232 GDM as the graphical login manager. You should then
16233 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
16234 also try starting GNOME on Wayland manually from a TTY with the
16235 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
16236 gnome-session``. Currently only GNOME has support for Wayland.
16238 @defvr {Scheme Variable} gnome-desktop-service-type
16239 This is the type of the service that adds the @uref{https://www.gnome.org,
16240 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
16241 object (see below).
16243 This service adds the @code{gnome} package to the system profile, and extends
16244 polkit with the actions from @code{gnome-settings-daemon}.
16247 @deftp {Data Type} gnome-desktop-configuration
16248 Configuration record for the GNOME desktop environment.
16251 @item @code{gnome} (default: @code{gnome})
16252 The GNOME package to use.
16256 @defvr {Scheme Variable} xfce-desktop-service-type
16257 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
16258 desktop environment. Its value is an @code{xfce-desktop-configuration} object
16261 This service adds the @code{xfce} package to the system profile, and
16262 extends polkit with the ability for @code{thunar} to manipulate the file
16263 system as root from within a user session, after the user has authenticated
16264 with the administrator's password.
16267 @deftp {Data Type} xfce-desktop-configuration
16268 Configuration record for the Xfce desktop environment.
16271 @item @code{xfce} (default: @code{xfce})
16272 The Xfce package to use.
16276 @deffn {Scheme Variable} mate-desktop-service-type
16277 This is the type of the service that runs the @uref{https://mate-desktop.org/,
16278 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
16279 object (see below).
16281 This service adds the @code{mate} package to the system
16282 profile, and extends polkit with the actions from
16283 @code{mate-settings-daemon}.
16286 @deftp {Data Type} mate-desktop-configuration
16287 Configuration record for the MATE desktop environment.
16290 @item @code{mate} (default: @code{mate})
16291 The MATE package to use.
16295 @deffn {Scheme Variable} enlightenment-desktop-service-type
16296 Return a service that adds the @code{enlightenment} package to the system
16297 profile, and extends dbus with actions from @code{efl}.
16300 @deftp {Data Type} enlightenment-desktop-service-configuration
16302 @item @code{enlightenment} (default: @code{enlightenment})
16303 The enlightenment package to use.
16307 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
16308 the default @code{%desktop-services} variable doesn't include any of
16309 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
16310 @code{%desktop-services} in the @code{services} field of your
16311 @code{operating-system}:
16314 (use-modules (gnu))
16315 (use-service-modules desktop)
16318 ;; cons* adds items to the list given as its last argument.
16319 (services (cons* (service gnome-desktop-service-type)
16320 (service xfce-desktop-service)
16321 %desktop-services))
16325 These desktop environments will then be available as options in the
16326 graphical login window.
16328 The actual service definitions included in @code{%desktop-services} and
16329 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
16330 are described below.
16332 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
16333 Return a service that runs the ``system bus'', using @var{dbus}, with
16334 support for @var{services}.
16336 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
16337 facility. Its system bus is used to allow system services to communicate
16338 and to be notified of system-wide events.
16340 @var{services} must be a list of packages that provide an
16341 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
16342 and policy files. For example, to allow avahi-daemon to use the system bus,
16343 @var{services} must be equal to @code{(list avahi)}.
16346 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
16347 Return a service that runs the @code{elogind} login and
16348 seat management daemon. @uref{https://github.com/elogind/elogind,
16349 Elogind} exposes a D-Bus interface that can be used to know which users
16350 are logged in, know what kind of sessions they have open, suspend the
16351 system, inhibit system suspend, reboot the system, and other tasks.
16353 Elogind handles most system-level power events for a computer, for
16354 example suspending the system when a lid is closed, or shutting it down
16355 when the power button is pressed.
16357 The @var{config} keyword argument specifies the configuration for
16358 elogind, and should be the result of an @code{(elogind-configuration
16359 (@var{parameter} @var{value})...)} invocation. Available parameters and
16360 their default values are:
16363 @item kill-user-processes?
16365 @item kill-only-users
16367 @item kill-exclude-users
16369 @item inhibit-delay-max-seconds
16371 @item handle-power-key
16373 @item handle-suspend-key
16375 @item handle-hibernate-key
16377 @item handle-lid-switch
16379 @item handle-lid-switch-docked
16381 @item power-key-ignore-inhibited?
16383 @item suspend-key-ignore-inhibited?
16385 @item hibernate-key-ignore-inhibited?
16387 @item lid-switch-ignore-inhibited?
16389 @item holdoff-timeout-seconds
16393 @item idle-action-seconds
16395 @item runtime-directory-size-percent
16397 @item runtime-directory-size
16401 @item suspend-state
16402 @code{("mem" "standby" "freeze")}
16405 @item hibernate-state
16407 @item hibernate-mode
16408 @code{("platform" "shutdown")}
16409 @item hybrid-sleep-state
16411 @item hybrid-sleep-mode
16412 @code{("suspend" "platform" "shutdown")}
16416 @deffn {Scheme Procedure} accountsservice-service @
16417 [#:accountsservice @var{accountsservice}]
16418 Return a service that runs AccountsService, a system service that can
16419 list available accounts, change their passwords, and so on.
16420 AccountsService integrates with PolicyKit to enable unprivileged users
16421 to acquire the capability to modify their system configuration.
16422 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
16423 accountsservice web site} for more information.
16425 The @var{accountsservice} keyword argument is the @code{accountsservice}
16426 package to expose as a service.
16429 @deffn {Scheme Procedure} polkit-service @
16430 [#:polkit @var{polkit}]
16431 Return a service that runs the
16432 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
16433 management service}, which allows system administrators to grant access to
16434 privileged operations in a structured way. By querying the Polkit service, a
16435 privileged system component can know when it should grant additional
16436 capabilities to ordinary users. For example, an ordinary user can be granted
16437 the capability to suspend the system if the user is logged in locally.
16440 @defvr {Scheme Variable} polkit-wheel-service
16441 Service that adds the @code{wheel} group as admins to the Polkit
16442 service. This makes it so that users in the @code{wheel} group are queried
16443 for their own passwords when performing administrative actions instead of
16444 @code{root}'s, similar to the behaviour used by @code{sudo}.
16447 @defvr {Scheme Variable} upower-service-type
16448 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
16449 system-wide monitor for power consumption and battery levels, with the given
16450 configuration settings.
16452 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
16453 notably used by GNOME.
16456 @deftp {Data Type} upower-configuration
16457 Data type representation the configuration for UPower.
16461 @item @code{upower} (default: @var{upower})
16462 Package to use for @code{upower}.
16464 @item @code{watts-up-pro?} (default: @code{#f})
16465 Enable the Watts Up Pro device.
16467 @item @code{poll-batteries?} (default: @code{#t})
16468 Enable polling the kernel for battery level changes.
16470 @item @code{ignore-lid?} (default: @code{#f})
16471 Ignore the lid state, this can be useful if it's incorrect on a device.
16473 @item @code{use-percentage-for-policy?} (default: @code{#f})
16474 Whether battery percentage based policy should be used. The default is to use
16475 the time left, change to @code{#t} to use the percentage.
16477 @item @code{percentage-low} (default: @code{10})
16478 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16479 at which the battery is considered low.
16481 @item @code{percentage-critical} (default: @code{3})
16482 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16483 at which the battery is considered critical.
16485 @item @code{percentage-action} (default: @code{2})
16486 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16487 at which action will be taken.
16489 @item @code{time-low} (default: @code{1200})
16490 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16491 seconds at which the battery is considered low.
16493 @item @code{time-critical} (default: @code{300})
16494 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16495 seconds at which the battery is considered critical.
16497 @item @code{time-action} (default: @code{120})
16498 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16499 seconds at which action will be taken.
16501 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
16502 The action taken when @code{percentage-action} or @code{time-action} is
16503 reached (depending on the configuration of @code{use-percentage-for-policy?}).
16505 Possible values are:
16515 @code{'hybrid-sleep}.
16521 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
16522 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
16523 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
16524 notifications and ways to mount/unmount disks. Programs that talk to UDisks
16525 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
16528 @deffn {Scheme Variable} colord-service-type
16529 This is the type of the service that runs @command{colord}, a system
16530 service with a D-Bus
16531 interface to manage the color profiles of input and output devices such as
16532 screens and scanners. It is notably used by the GNOME Color Manager graphical
16533 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
16534 site} for more information.
16537 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
16538 Return a configuration allowing an application to access GeoClue
16539 location data. @var{name} is the Desktop ID of the application, without
16540 the @code{.desktop} part. If @var{allowed?} is true, the application
16541 will have access to location information by default. The boolean
16542 @var{system?} value indicates whether an application is a system component
16543 or not. Finally @var{users} is a list of UIDs of all users for which
16544 this application is allowed location info access. An empty users list
16545 means that all users are allowed.
16548 @cindex scanner access
16549 @deffn {Scheme Procedure} sane-service-type
16550 This service provides access to scanners @i{via}
16551 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
16555 @defvr {Scheme Variable} %standard-geoclue-applications
16556 The standard list of well-known GeoClue application configurations,
16557 granting authority to the GNOME date-and-time utility to ask for the
16558 current location in order to set the time zone, and allowing the
16559 IceCat and Epiphany web browsers to request location information.
16560 IceCat and Epiphany both query the user before allowing a web page to
16561 know the user's location.
16564 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
16565 [#:whitelist '()] @
16566 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
16567 [#:submit-data? #f]
16568 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
16569 [#:submission-nick "geoclue"] @
16570 [#:applications %standard-geoclue-applications]
16571 Return a service that runs the GeoClue location service. This service
16572 provides a D-Bus interface to allow applications to request access to a
16573 user's physical location, and optionally to add information to online
16574 location databases. See
16575 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
16576 web site} for more information.
16579 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
16580 [@w{#:auto-enable? #f}]
16581 Return a service that runs the @command{bluetoothd} daemon, which
16582 manages all the Bluetooth devices and provides a number of D-Bus
16583 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
16584 powered automatically at boot, which can be useful when using a
16585 bluetooth keyboard or mouse.
16587 Users need to be in the @code{lp} group to access the D-Bus service.
16590 @defvr {Scheme Variable} gnome-keyring-service-type
16591 This is the type of the service that adds the
16592 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
16593 value is a @code{gnome-keyring-configuration} object (see below).
16595 This service adds the @code{gnome-keyring} package to the system profile
16596 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
16597 a user's login keyring when they log in or setting its password with passwd.
16600 @deftp {Data Type} gnome-keyring-configuration
16601 Configuration record for the GNOME Keyring service.
16604 @item @code{keyring} (default: @code{gnome-keyring})
16605 The GNOME keyring package to use.
16607 @item @code{pam-services}
16608 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
16609 services to extend, where @var{service} is the name of an existing
16610 service to extend and @var{kind} is one of @code{login} or
16613 If @code{login} is given, it adds an optional
16614 @code{pam_gnome_keyring.so} to the auth block without arguments and to
16615 the session block with @code{auto_start}. If @code{passwd} is given, it
16616 adds an optional @code{pam_gnome_keyring.so} to the password block
16619 By default, this field contains ``gdm-password'' with the value @code{login}
16620 and ``passwd'' is with the value @code{passwd}.
16625 @node Sound Services
16626 @subsection Sound Services
16628 @cindex sound support
16630 @cindex PulseAudio, sound support
16632 The @code{(gnu services sound)} module provides a service to configure the
16633 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
16634 preferred ALSA output driver.
16636 @deffn {Scheme Variable} alsa-service-type
16637 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
16638 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
16639 configuration file. The value for this type is a @command{alsa-configuration}
16640 record as in this example:
16643 (service alsa-service-type)
16646 See below for details about @code{alsa-configuration}.
16649 @deftp {Data Type} alsa-configuration
16650 Data type representing the configuration for @code{alsa-service}.
16653 @item @code{alsa-plugins} (default: @var{alsa-plugins})
16654 @code{alsa-plugins} package to use.
16656 @item @code{pulseaudio?} (default: @var{#t})
16657 Whether ALSA applications should transparently be made to use the
16658 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
16660 Using PulseAudio allows you to run several sound-producing applications
16661 at the same time and to individual control them @i{via}
16662 @command{pavucontrol}, among other things.
16664 @item @code{extra-options} (default: @var{""})
16665 String to append to the @file{/etc/asound.conf} file.
16670 Individual users who want to override the system configuration of ALSA can do
16671 it with the @file{~/.asoundrc} file:
16674 # In guix, we have to specify the absolute path for plugins.
16676 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
16679 # Routing ALSA to jack:
16680 # <http://jackaudio.org/faq/routing_alsa.html>.
16684 0 system:playback_1
16685 1 system:playback_2
16702 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
16705 @deffn {Scheme Variable} pulseaudio-service-type
16706 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
16707 sound server. It exists to allow system overrides of the default settings
16708 via @code{pulseaudio-configuration}, see below.
16711 This service overrides per-user configuration files. If you want
16712 PulseAudio to honor configuraton files in @file{~/.config/pulse} you
16713 have to unset the environment variables @env{PULSE_CONFIG} and
16714 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
16718 This service on its own does not ensure, that the @code{pulseaudio} package
16719 exists on your machine. It merely adds configuration files for it, as
16720 detailed below. In the (admittedly unlikely) case, that you find yourself
16721 without a @code{pulseaudio} package, consider enabling it through the
16722 @code{alsa-service-type} above.
16726 @deftp {Data Type} pulseaudio-configuration
16727 Data type representing the configuration for @code{pulseaudio-service}.
16730 @item @var{client-conf} (default: @code{'()})
16731 List of settings to set in @file{client.conf}.
16732 Accepts a list of strings or a symbol-value pairs. A string will be
16733 inserted as-is with a newline added. A pair will be formatted as
16734 ``key = value'', again with a newline added.
16736 @item @var{daemon-conf} (default: @code{'((flat-volumes . no))})
16737 List of settings to set in @file{daemon.conf}, formatted just like
16740 @item @var{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
16741 Script file to use as as @file{default.pa}.
16743 @item @var{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
16744 Script file to use as as @file{system.pa}.
16748 @deffn {Scheme Variable} ladspa-service-type
16749 This service sets the @var{LADSPA_PATH} variable, so that programs, which
16750 respect it, e.g. PulseAudio, can load LADSPA plugins.
16752 The following example will setup the service to enable modules from the
16753 @code{swh-plugins} package:
16756 (service ladspa-service-type
16757 (ladspa-configuration (plugins (list swh-plugins))))
16760 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
16765 @node Database Services
16766 @subsection Database Services
16770 The @code{(gnu services databases)} module provides the following services.
16772 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
16773 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
16774 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
16775 Return a service that runs @var{postgresql}, the PostgreSQL database
16778 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
16779 creates a database cluster with @var{locale} as the default
16780 locale, stored in @var{data-directory}. It then listens on @var{port}.
16782 @cindex postgresql extension-packages
16783 Additional extensions are loaded from packages listed in
16784 @var{extension-packages}. Extensions are available at runtime. For instance,
16785 to create a geographic database using the @code{postgis} extension, a user can
16786 configure the postgresql-service as in this example:
16790 (use-package-modules databases geo)
16794 ;; postgresql is required to run `psql' but postgis is not required for
16795 ;; proper operation.
16796 (packages (cons* postgresql %base-packages))
16799 (postgresql-service #:extension-packages (list postgis))
16803 Then the extension becomes visible and you can initialise an empty geographic
16804 database in this way:
16808 > create database postgistest;
16809 > \connect postgistest;
16810 > create extension postgis;
16811 > create extension postgis_topology;
16814 There is no need to add this field for contrib extensions such as hstore or
16815 dblink as they are already loadable by postgresql. This field is only
16816 required to add extensions provided by other packages.
16819 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
16820 Return a service that runs @command{mysqld}, the MySQL or MariaDB
16823 The optional @var{config} argument specifies the configuration for
16824 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
16827 @deftp {Data Type} mysql-configuration
16828 Data type representing the configuration of @var{mysql-service}.
16831 @item @code{mysql} (default: @var{mariadb})
16832 Package object of the MySQL database server, can be either @var{mariadb}
16835 For MySQL, a temporary root password will be displayed at activation time.
16836 For MariaDB, the root password is empty.
16838 @item @code{port} (default: @code{3306})
16839 TCP port on which the database server listens for incoming connections.
16843 @defvr {Scheme Variable} memcached-service-type
16844 This is the service type for the @uref{https://memcached.org/,
16845 Memcached} service, which provides a distributed in memory cache. The
16846 value for the service type is a @code{memcached-configuration} object.
16850 (service memcached-service-type)
16853 @deftp {Data Type} memcached-configuration
16854 Data type representing the configuration of memcached.
16857 @item @code{memcached} (default: @code{memcached})
16858 The Memcached package to use.
16860 @item @code{interfaces} (default: @code{'("0.0.0.0")})
16861 Network interfaces on which to listen.
16863 @item @code{tcp-port} (default: @code{11211})
16864 Port on which to accept connections on,
16866 @item @code{udp-port} (default: @code{11211})
16867 Port on which to accept UDP connections on, a value of 0 will disable
16868 listening on a UDP socket.
16870 @item @code{additional-options} (default: @code{'()})
16871 Additional command line options to pass to @code{memcached}.
16875 @defvr {Scheme Variable} mongodb-service-type
16876 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
16877 The value for the service type is a @code{mongodb-configuration} object.
16881 (service mongodb-service-type)
16884 @deftp {Data Type} mongodb-configuration
16885 Data type representing the configuration of mongodb.
16888 @item @code{mongodb} (default: @code{mongodb})
16889 The MongoDB package to use.
16891 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
16892 The configuration file for MongoDB.
16894 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
16895 This value is used to create the directory, so that it exists and is
16896 owned by the mongodb user. It should match the data-directory which
16897 MongoDB is configured to use through the configuration file.
16901 @defvr {Scheme Variable} redis-service-type
16902 This is the service type for the @uref{https://redis.io/, Redis}
16903 key/value store, whose value is a @code{redis-configuration} object.
16906 @deftp {Data Type} redis-configuration
16907 Data type representing the configuration of redis.
16910 @item @code{redis} (default: @code{redis})
16911 The Redis package to use.
16913 @item @code{bind} (default: @code{"127.0.0.1"})
16914 Network interface on which to listen.
16916 @item @code{port} (default: @code{6379})
16917 Port on which to accept connections on, a value of 0 will disable
16918 listening on a TCP socket.
16920 @item @code{working-directory} (default: @code{"/var/lib/redis"})
16921 Directory in which to store the database and related files.
16925 @node Mail Services
16926 @subsection Mail Services
16930 The @code{(gnu services mail)} module provides Guix service definitions
16931 for email services: IMAP, POP3, and LMTP servers, as well as mail
16932 transport agents (MTAs). Lots of acronyms! These services are detailed
16933 in the subsections below.
16935 @subsubheading Dovecot Service
16937 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
16938 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
16941 By default, Dovecot does not need much configuration; the default
16942 configuration object created by @code{(dovecot-configuration)} will
16943 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
16944 certificate will be generated for TLS-protected connections, though
16945 Dovecot will also listen on cleartext ports by default. There are a
16946 number of options, though, which mail administrators might need to change,
16947 and as is the case with other services, Guix allows the system
16948 administrator to specify these parameters via a uniform Scheme interface.
16950 For example, to specify that mail is located at @code{maildir~/.mail},
16951 one would instantiate the Dovecot service like this:
16954 (dovecot-service #:config
16955 (dovecot-configuration
16956 (mail-location "maildir:~/.mail")))
16959 The available configuration parameters follow. Each parameter
16960 definition is preceded by its type; for example, @samp{string-list foo}
16961 indicates that the @code{foo} parameter should be specified as a list of
16962 strings. There is also a way to specify the configuration as a string,
16963 if you have an old @code{dovecot.conf} file that you want to port over
16964 from some other system; see the end for more details.
16966 @c The following documentation was initially generated by
16967 @c (generate-documentation) in (gnu services mail). Manually maintained
16968 @c documentation is better, so we shouldn't hesitate to edit below as
16969 @c needed. However if the change you want to make to this documentation
16970 @c can be done in an automated way, it's probably easier to change
16971 @c (generate-documentation) than to make it below and have to deal with
16972 @c the churn as dovecot updates.
16974 Available @code{dovecot-configuration} fields are:
16976 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
16977 The dovecot package.
16980 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
16981 A list of IPs or hosts where to listen for connections. @samp{*}
16982 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
16983 interfaces. If you want to specify non-default ports or anything more
16984 complex, customize the address and port fields of the
16985 @samp{inet-listener} of the specific services you are interested in.
16988 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
16989 List of protocols we want to serve. Available protocols include
16990 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
16992 Available @code{protocol-configuration} fields are:
16994 @deftypevr {@code{protocol-configuration} parameter} string name
16995 The name of the protocol.
16998 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
16999 UNIX socket path to the master authentication server to find users.
17000 This is used by imap (for shared users) and lda.
17001 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17004 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
17005 Space separated list of plugins to load.
17008 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
17009 Maximum number of IMAP connections allowed for a user from each IP
17010 address. NOTE: The username is compared case-sensitively.
17011 Defaults to @samp{10}.
17016 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
17017 List of services to enable. Available services include @samp{imap},
17018 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
17021 Available @code{service-configuration} fields are:
17023 @deftypevr {@code{service-configuration} parameter} string kind
17024 The service kind. Valid values include @code{director},
17025 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
17026 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
17027 @code{tcpwrap}, @code{quota-warning}, or anything else.
17030 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
17031 Listeners for the service. A listener is either a
17032 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
17033 an @code{inet-listener-configuration}.
17034 Defaults to @samp{()}.
17036 Available @code{unix-listener-configuration} fields are:
17038 @deftypevr {@code{unix-listener-configuration} parameter} string path
17039 Path to the file, relative to @code{base-dir} field. This is also used as
17043 @deftypevr {@code{unix-listener-configuration} parameter} string mode
17044 The access mode for the socket.
17045 Defaults to @samp{"0600"}.
17048 @deftypevr {@code{unix-listener-configuration} parameter} string user
17049 The user to own the socket.
17050 Defaults to @samp{""}.
17053 @deftypevr {@code{unix-listener-configuration} parameter} string group
17054 The group to own the socket.
17055 Defaults to @samp{""}.
17059 Available @code{fifo-listener-configuration} fields are:
17061 @deftypevr {@code{fifo-listener-configuration} parameter} string path
17062 Path to the file, relative to @code{base-dir} field. This is also used as
17066 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
17067 The access mode for the socket.
17068 Defaults to @samp{"0600"}.
17071 @deftypevr {@code{fifo-listener-configuration} parameter} string user
17072 The user to own the socket.
17073 Defaults to @samp{""}.
17076 @deftypevr {@code{fifo-listener-configuration} parameter} string group
17077 The group to own the socket.
17078 Defaults to @samp{""}.
17082 Available @code{inet-listener-configuration} fields are:
17084 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
17085 The protocol to listen for.
17088 @deftypevr {@code{inet-listener-configuration} parameter} string address
17089 The address on which to listen, or empty for all addresses.
17090 Defaults to @samp{""}.
17093 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
17094 The port on which to listen.
17097 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
17098 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
17100 Defaults to @samp{#t}.
17105 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
17106 Maximum number of simultaneous client connections per process. Once
17107 this number of connections is received, the next incoming connection
17108 will prompt Dovecot to spawn another process. If set to 0,
17109 @code{default-client-limit} is used instead.
17111 Defaults to @samp{0}.
17115 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
17116 Number of connections to handle before starting a new process.
17117 Typically the only useful values are 0 (unlimited) or 1. 1 is more
17118 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
17119 Defaults to @samp{1}.
17123 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
17124 Maximum number of processes that can exist for this service. If set to
17125 0, @code{default-process-limit} is used instead.
17127 Defaults to @samp{0}.
17131 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
17132 Number of processes to always keep waiting for more connections.
17133 Defaults to @samp{0}.
17136 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
17137 If you set @samp{service-count 0}, you probably need to grow
17139 Defaults to @samp{256000000}.
17144 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
17145 Dict configuration, as created by the @code{dict-configuration}
17148 Available @code{dict-configuration} fields are:
17150 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
17151 A list of key-value pairs that this dict should hold.
17152 Defaults to @samp{()}.
17157 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
17158 A list of passdb configurations, each one created by the
17159 @code{passdb-configuration} constructor.
17161 Available @code{passdb-configuration} fields are:
17163 @deftypevr {@code{passdb-configuration} parameter} string driver
17164 The driver that the passdb should use. Valid values include
17165 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
17167 Defaults to @samp{"pam"}.
17170 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
17171 Space separated list of arguments to the passdb driver.
17172 Defaults to @samp{""}.
17177 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
17178 List of userdb configurations, each one created by the
17179 @code{userdb-configuration} constructor.
17181 Available @code{userdb-configuration} fields are:
17183 @deftypevr {@code{userdb-configuration} parameter} string driver
17184 The driver that the userdb should use. Valid values include
17185 @samp{passwd} and @samp{static}.
17186 Defaults to @samp{"passwd"}.
17189 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
17190 Space separated list of arguments to the userdb driver.
17191 Defaults to @samp{""}.
17194 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
17195 Override fields from passwd.
17196 Defaults to @samp{()}.
17201 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
17202 Plug-in configuration, created by the @code{plugin-configuration}
17206 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
17207 List of namespaces. Each item in the list is created by the
17208 @code{namespace-configuration} constructor.
17210 Available @code{namespace-configuration} fields are:
17212 @deftypevr {@code{namespace-configuration} parameter} string name
17213 Name for this namespace.
17216 @deftypevr {@code{namespace-configuration} parameter} string type
17217 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
17218 Defaults to @samp{"private"}.
17221 @deftypevr {@code{namespace-configuration} parameter} string separator
17222 Hierarchy separator to use. You should use the same separator for
17223 all namespaces or some clients get confused. @samp{/} is usually a good
17224 one. The default however depends on the underlying mail storage
17226 Defaults to @samp{""}.
17229 @deftypevr {@code{namespace-configuration} parameter} string prefix
17230 Prefix required to access this namespace. This needs to be
17231 different for all namespaces. For example @samp{Public/}.
17232 Defaults to @samp{""}.
17235 @deftypevr {@code{namespace-configuration} parameter} string location
17236 Physical location of the mailbox. This is in the same format as
17237 mail_location, which is also the default for it.
17238 Defaults to @samp{""}.
17241 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
17242 There can be only one INBOX, and this setting defines which
17244 Defaults to @samp{#f}.
17247 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
17248 If namespace is hidden, it's not advertised to clients via NAMESPACE
17249 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
17250 useful when converting from another server with different namespaces
17251 which you want to deprecate but still keep working. For example you can
17252 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
17254 Defaults to @samp{#f}.
17257 @deftypevr {@code{namespace-configuration} parameter} boolean list?
17258 Show the mailboxes under this namespace with the LIST command. This
17259 makes the namespace visible for clients that do not support the NAMESPACE
17260 extension. The special @code{children} value lists child mailboxes, but
17261 hides the namespace prefix.
17262 Defaults to @samp{#t}.
17265 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
17266 Namespace handles its own subscriptions. If set to @code{#f}, the
17267 parent namespace handles them. The empty prefix should always have this
17269 Defaults to @samp{#t}.
17272 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
17273 List of predefined mailboxes in this namespace.
17274 Defaults to @samp{()}.
17276 Available @code{mailbox-configuration} fields are:
17278 @deftypevr {@code{mailbox-configuration} parameter} string name
17279 Name for this mailbox.
17282 @deftypevr {@code{mailbox-configuration} parameter} string auto
17283 @samp{create} will automatically create this mailbox.
17284 @samp{subscribe} will both create and subscribe to the mailbox.
17285 Defaults to @samp{"no"}.
17288 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
17289 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
17290 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
17291 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
17292 Defaults to @samp{()}.
17299 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
17300 Base directory where to store runtime data.
17301 Defaults to @samp{"/var/run/dovecot/"}.
17304 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
17305 Greeting message for clients.
17306 Defaults to @samp{"Dovecot ready."}.
17309 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
17310 List of trusted network ranges. Connections from these IPs are
17311 allowed to override their IP addresses and ports (for logging and for
17312 authentication checks). @samp{disable-plaintext-auth} is also ignored
17313 for these networks. Typically you would specify your IMAP proxy servers
17315 Defaults to @samp{()}.
17318 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
17319 List of login access check sockets (e.g.@: tcpwrap).
17320 Defaults to @samp{()}.
17323 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
17324 Show more verbose process titles (in ps). Currently shows user name
17325 and IP address. Useful for seeing who is actually using the IMAP
17326 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
17328 Defaults to @samp{#f}.
17331 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
17332 Should all processes be killed when Dovecot master process shuts down.
17333 Setting this to @code{#f} means that Dovecot can be upgraded without
17334 forcing existing client connections to close (although that could also
17335 be a problem if the upgrade is e.g.@: due to a security fix).
17336 Defaults to @samp{#t}.
17339 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
17340 If non-zero, run mail commands via this many connections to doveadm
17341 server, instead of running them directly in the same process.
17342 Defaults to @samp{0}.
17345 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
17346 UNIX socket or host:port used for connecting to doveadm server.
17347 Defaults to @samp{"doveadm-server"}.
17350 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
17351 List of environment variables that are preserved on Dovecot startup
17352 and passed down to all of its child processes. You can also give
17353 key=value pairs to always set specific settings.
17356 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
17357 Disable LOGIN command and all other plaintext authentications unless
17358 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
17359 matches the local IP (i.e.@: you're connecting from the same computer),
17360 the connection is considered secure and plaintext authentication is
17361 allowed. See also ssl=required setting.
17362 Defaults to @samp{#t}.
17365 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
17366 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
17367 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
17368 for caching to be used.
17369 Defaults to @samp{0}.
17372 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
17373 Time to live for cached data. After TTL expires the cached record
17374 is no longer used, *except* if the main database lookup returns internal
17375 failure. We also try to handle password changes automatically: If
17376 user's previous authentication was successful, but this one wasn't, the
17377 cache isn't used. For now this works only with plaintext
17379 Defaults to @samp{"1 hour"}.
17382 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
17383 TTL for negative hits (user not found, password mismatch).
17384 0 disables caching them completely.
17385 Defaults to @samp{"1 hour"}.
17388 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
17389 List of realms for SASL authentication mechanisms that need them.
17390 You can leave it empty if you don't want to support multiple realms.
17391 Many clients simply use the first one listed here, so keep the default
17393 Defaults to @samp{()}.
17396 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
17397 Default realm/domain to use if none was specified. This is used for
17398 both SASL realms and appending @@domain to username in plaintext
17400 Defaults to @samp{""}.
17403 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
17404 List of allowed characters in username. If the user-given username
17405 contains a character not listed in here, the login automatically fails.
17406 This is just an extra check to make sure user can't exploit any
17407 potential quote escaping vulnerabilities with SQL/LDAP databases. If
17408 you want to allow all characters, set this value to empty.
17409 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
17412 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
17413 Username character translations before it's looked up from
17414 databases. The value contains series of from -> to characters. For
17415 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
17416 translated to @samp{@@}.
17417 Defaults to @samp{""}.
17420 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
17421 Username formatting before it's looked up from databases. You can
17422 use the standard variables here, e.g.@: %Lu would lowercase the username,
17423 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
17424 change the @samp{@@} into @samp{-AT-}. This translation is done after
17425 @samp{auth-username-translation} changes.
17426 Defaults to @samp{"%Lu"}.
17429 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
17430 If you want to allow master users to log in by specifying the master
17431 username within the normal username string (i.e.@: not using SASL
17432 mechanism's support for it), you can specify the separator character
17433 here. The format is then <username><separator><master username>.
17434 UW-IMAP uses @samp{*} as the separator, so that could be a good
17436 Defaults to @samp{""}.
17439 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
17440 Username to use for users logging in with ANONYMOUS SASL
17442 Defaults to @samp{"anonymous"}.
17445 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
17446 Maximum number of dovecot-auth worker processes. They're used to
17447 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
17448 They're automatically created and destroyed as needed.
17449 Defaults to @samp{30}.
17452 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
17453 Host name to use in GSSAPI principal names. The default is to use
17454 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
17455 allow all keytab entries.
17456 Defaults to @samp{""}.
17459 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
17460 Kerberos keytab to use for the GSSAPI mechanism. Will use the
17461 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
17462 need to change the auth service to run as root to be able to read this
17464 Defaults to @samp{""}.
17467 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
17468 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
17469 and @samp{ntlm-auth} helper.
17470 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
17471 Defaults to @samp{#f}.
17474 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
17475 Path for Samba's @samp{ntlm-auth} helper binary.
17476 Defaults to @samp{"/usr/bin/ntlm_auth"}.
17479 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
17480 Time to delay before replying to failed authentications.
17481 Defaults to @samp{"2 secs"}.
17484 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
17485 Require a valid SSL client certificate or the authentication
17487 Defaults to @samp{#f}.
17490 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
17491 Take the username from client's SSL certificate, using
17492 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
17494 Defaults to @samp{#f}.
17497 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
17498 List of wanted authentication mechanisms. Supported mechanisms are:
17499 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
17500 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
17501 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
17502 @samp{disable-plaintext-auth} setting.
17505 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
17506 List of IPs or hostnames to all director servers, including ourself.
17507 Ports can be specified as ip:port. The default port is the same as what
17508 director service's @samp{inet-listener} is using.
17509 Defaults to @samp{()}.
17512 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
17513 List of IPs or hostnames to all backend mail servers. Ranges are
17514 allowed too, like 10.0.0.10-10.0.0.30.
17515 Defaults to @samp{()}.
17518 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
17519 How long to redirect users to a specific server after it no longer
17520 has any connections.
17521 Defaults to @samp{"15 min"}.
17524 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
17525 How the username is translated before being hashed. Useful values
17526 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
17527 are shared within domain.
17528 Defaults to @samp{"%Lu"}.
17531 @deftypevr {@code{dovecot-configuration} parameter} string log-path
17532 Log file to use for error messages. @samp{syslog} logs to syslog,
17533 @samp{/dev/stderr} logs to stderr.
17534 Defaults to @samp{"syslog"}.
17537 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
17538 Log file to use for informational messages. Defaults to
17540 Defaults to @samp{""}.
17543 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
17544 Log file to use for debug messages. Defaults to
17545 @samp{info-log-path}.
17546 Defaults to @samp{""}.
17549 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
17550 Syslog facility to use if you're logging to syslog. Usually if you
17551 don't want to use @samp{mail}, you'll use local0..local7. Also other
17552 standard facilities are supported.
17553 Defaults to @samp{"mail"}.
17556 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
17557 Log unsuccessful authentication attempts and the reasons why they
17559 Defaults to @samp{#f}.
17562 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
17563 In case of password mismatches, log the attempted password. Valid
17564 values are no, plain and sha1. sha1 can be useful for detecting brute
17565 force password attempts vs. user simply trying the same password over
17566 and over again. You can also truncate the value to n chars by appending
17567 ":n" (e.g.@: sha1:6).
17568 Defaults to @samp{"no"}.
17571 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
17572 Even more verbose logging for debugging purposes. Shows for example
17574 Defaults to @samp{#f}.
17577 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
17578 In case of password mismatches, log the passwords and used scheme so
17579 the problem can be debugged. Enabling this also enables
17581 Defaults to @samp{#f}.
17584 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
17585 Enable mail process debugging. This can help you figure out why
17586 Dovecot isn't finding your mails.
17587 Defaults to @samp{#f}.
17590 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
17591 Show protocol level SSL errors.
17592 Defaults to @samp{#f}.
17595 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
17596 Prefix for each line written to log file. % codes are in
17597 strftime(3) format.
17598 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
17601 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
17602 List of elements we want to log. The elements which have a
17603 non-empty variable value are joined together to form a comma-separated
17607 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
17608 Login log format. %s contains @samp{login-log-format-elements}
17609 string, %$ contains the data we want to log.
17610 Defaults to @samp{"%$: %s"}.
17613 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
17614 Log prefix for mail processes. See doc/wiki/Variables.txt for list
17615 of possible variables you can use.
17616 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
17619 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
17620 Format to use for logging mail deliveries. You can use variables:
17623 Delivery status message (e.g.@: @samp{saved to INBOX})
17635 Defaults to @samp{"msgid=%m: %$"}.
17638 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
17639 Location for users' mailboxes. The default is empty, which means
17640 that Dovecot tries to find the mailboxes automatically. This won't work
17641 if the user doesn't yet have any mail, so you should explicitly tell
17642 Dovecot the full location.
17644 If you're using mbox, giving a path to the INBOX
17645 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
17646 where the other mailboxes are kept. This is called the @emph{root mail
17647 directory}, and it must be the first path given in the
17648 @samp{mail-location} setting.
17650 There are a few special variables you can use, e.g.:
17656 user part in user@@domain, same as %u if there's no domain
17658 domain part in user@@domain, empty if there's no domain
17663 See doc/wiki/Variables.txt for full list. Some examples:
17665 @item maildir:~/Maildir
17666 @item mbox:~/mail:INBOX=/var/mail/%u
17667 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
17669 Defaults to @samp{""}.
17672 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
17673 System user and group used to access mails. If you use multiple,
17674 userdb can override these by returning uid or gid fields. You can use
17675 either numbers or names. <doc/wiki/UserIds.txt>.
17676 Defaults to @samp{""}.
17679 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
17681 Defaults to @samp{""}.
17684 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
17685 Group to enable temporarily for privileged operations. Currently
17686 this is used only with INBOX when either its initial creation or
17687 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
17689 Defaults to @samp{""}.
17692 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
17693 Grant access to these supplementary groups for mail processes.
17694 Typically these are used to set up access to shared mailboxes. Note
17695 that it may be dangerous to set these if users can create symlinks
17696 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
17697 could allow a user to delete others' mailboxes, or @code{ln -s
17698 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
17702 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
17703 Allow full file system access to clients. There's no access checks
17704 other than what the operating system does for the active UID/GID. It
17705 works with both maildir and mboxes, allowing you to prefix mailboxes
17706 names with e.g.@: @file{/path/} or @file{~user/}.
17707 Defaults to @samp{#f}.
17710 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
17711 Don't use @code{mmap()} at all. This is required if you store indexes to
17712 shared file systems (NFS or clustered file system).
17713 Defaults to @samp{#f}.
17716 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
17717 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
17718 supports @samp{O_EXCL} since version 3, so this should be safe to use
17719 nowadays by default.
17720 Defaults to @samp{#t}.
17723 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
17724 When to use fsync() or fdatasync() calls:
17727 Whenever necessary to avoid losing important data
17729 Useful with e.g.@: NFS when @code{write()}s are delayed
17731 Never use it (best performance, but crashes can lose data).
17733 Defaults to @samp{"optimized"}.
17736 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
17737 Mail storage exists in NFS. Set this to yes to make Dovecot flush
17738 NFS caches whenever needed. If you're using only a single mail server
17740 Defaults to @samp{#f}.
17743 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
17744 Mail index files also exist in NFS. Setting this to yes requires
17745 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
17746 Defaults to @samp{#f}.
17749 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
17750 Locking method for index files. Alternatives are fcntl, flock and
17751 dotlock. Dotlocking uses some tricks which may create more disk I/O
17752 than other locking methods. NFS users: flock doesn't work, remember to
17753 change @samp{mmap-disable}.
17754 Defaults to @samp{"fcntl"}.
17757 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
17758 Directory in which LDA/LMTP temporarily stores incoming mails >128
17760 Defaults to @samp{"/tmp"}.
17763 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
17764 Valid UID range for users. This is mostly to make sure that users can't
17765 log in as daemons or other system users. Note that denying root logins is
17766 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
17768 Defaults to @samp{500}.
17771 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
17773 Defaults to @samp{0}.
17776 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
17777 Valid GID range for users. Users having non-valid GID as primary group ID
17778 aren't allowed to log in. If user belongs to supplementary groups with
17779 non-valid GIDs, those groups are not set.
17780 Defaults to @samp{1}.
17783 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
17785 Defaults to @samp{0}.
17788 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
17789 Maximum allowed length for mail keyword name. It's only forced when
17790 trying to create new keywords.
17791 Defaults to @samp{50}.
17794 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
17795 List of directories under which chrooting is allowed for mail
17796 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
17797 too). This setting doesn't affect @samp{login-chroot}
17798 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
17799 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
17800 which local users can modify, that may lead to root exploit. Usually
17801 this should be done only if you don't allow shell access for users.
17802 <doc/wiki/Chrooting.txt>.
17803 Defaults to @samp{()}.
17806 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
17807 Default chroot directory for mail processes. This can be overridden
17808 for specific users in user database by giving @samp{/./} in user's home
17809 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
17810 there is no real need to do chrooting, Dovecot doesn't allow users to
17811 access files outside their mail directory anyway. If your home
17812 directories are prefixed with the chroot directory, append @samp{/.} to
17813 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
17814 Defaults to @samp{""}.
17817 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
17818 UNIX socket path to master authentication server to find users.
17819 This is used by imap (for shared users) and lda.
17820 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17823 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
17824 Directory where to look up mail plugins.
17825 Defaults to @samp{"/usr/lib/dovecot"}.
17828 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
17829 List of plugins to load for all services. Plugins specific to IMAP,
17830 LDA, etc.@: are added to this list in their own .conf files.
17831 Defaults to @samp{()}.
17834 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
17835 The minimum number of mails in a mailbox before updates are done to
17836 cache file. This allows optimizing Dovecot's behavior to do less disk
17837 writes at the cost of more disk reads.
17838 Defaults to @samp{0}.
17841 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
17842 When IDLE command is running, mailbox is checked once in a while to
17843 see if there are any new mails or other changes. This setting defines
17844 the minimum time to wait between those checks. Dovecot can also use
17845 dnotify, inotify and kqueue to find out immediately when changes
17847 Defaults to @samp{"30 secs"}.
17850 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
17851 Save mails with CR+LF instead of plain LF. This makes sending those
17852 mails take less CPU, especially with sendfile() syscall with Linux and
17853 FreeBSD. But it also creates a bit more disk I/O which may just make it
17854 slower. Also note that if other software reads the mboxes/maildirs,
17855 they may handle the extra CRs wrong and cause problems.
17856 Defaults to @samp{#f}.
17859 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
17860 By default LIST command returns all entries in maildir beginning
17861 with a dot. Enabling this option makes Dovecot return only entries
17862 which are directories. This is done by stat()ing each entry, so it
17863 causes more disk I/O.
17864 (For systems setting struct @samp{dirent->d_type} this check is free
17865 and it's done always regardless of this setting).
17866 Defaults to @samp{#f}.
17869 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
17870 When copying a message, do it with hard links whenever possible.
17871 This makes the performance much better, and it's unlikely to have any
17873 Defaults to @samp{#t}.
17876 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
17877 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
17878 directory only when its mtime changes unexpectedly or when we can't find
17879 the mail otherwise.
17880 Defaults to @samp{#f}.
17883 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
17884 Which locking methods to use for locking mbox. There are four
17889 Create <mailbox>.lock file. This is the oldest and most NFS-safe
17890 solution. If you want to use /var/mail/ like directory, the users will
17891 need write access to that directory.
17893 Same as dotlock, but if it fails because of permissions or because there
17894 isn't enough disk space, just skip it.
17896 Use this if possible. Works with NFS too if lockd is used.
17898 May not exist in all systems. Doesn't work with NFS.
17900 May not exist in all systems. Doesn't work with NFS.
17903 You can use multiple locking methods; if you do the order they're declared
17904 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
17905 locking methods as well. Some operating systems don't allow using some of
17906 them simultaneously.
17909 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
17913 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
17914 Maximum time to wait for lock (all of them) before aborting.
17915 Defaults to @samp{"5 mins"}.
17918 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
17919 If dotlock exists but the mailbox isn't modified in any way,
17920 override the lock file after this much time.
17921 Defaults to @samp{"2 mins"}.
17924 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
17925 When mbox changes unexpectedly we have to fully read it to find out
17926 what changed. If the mbox is large this can take a long time. Since
17927 the change is usually just a newly appended mail, it'd be faster to
17928 simply read the new mails. If this setting is enabled, Dovecot does
17929 this but still safely fallbacks to re-reading the whole mbox file
17930 whenever something in mbox isn't how it's expected to be. The only real
17931 downside to this setting is that if some other MUA changes message
17932 flags, Dovecot doesn't notice it immediately. Note that a full sync is
17933 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
17934 Defaults to @samp{#t}.
17937 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
17938 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
17939 EXAMINE, EXPUNGE or CHECK commands. If this is set,
17940 @samp{mbox-dirty-syncs} is ignored.
17941 Defaults to @samp{#f}.
17944 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
17945 Delay writing mbox headers until doing a full write sync (EXPUNGE
17946 and CHECK commands and when closing the mailbox). This is especially
17947 useful for POP3 where clients often delete all mails. The downside is
17948 that our changes aren't immediately visible to other MUAs.
17949 Defaults to @samp{#t}.
17952 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
17953 If mbox size is smaller than this (e.g.@: 100k), don't write index
17954 files. If an index file already exists it's still read, just not
17956 Defaults to @samp{0}.
17959 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
17960 Maximum dbox file size until it's rotated.
17961 Defaults to @samp{10000000}.
17964 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
17965 Maximum dbox file age until it's rotated. Typically in days. Day
17966 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
17968 Defaults to @samp{"1d"}.
17971 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
17972 When creating new mdbox files, immediately preallocate their size to
17973 @samp{mdbox-rotate-size}. This setting currently works only in Linux
17974 with some file systems (ext4, xfs).
17975 Defaults to @samp{#f}.
17978 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
17979 sdbox and mdbox support saving mail attachments to external files,
17980 which also allows single instance storage for them. Other backends
17981 don't support this for now.
17983 WARNING: This feature hasn't been tested much yet. Use at your own risk.
17985 Directory root where to store mail attachments. Disabled, if empty.
17986 Defaults to @samp{""}.
17989 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
17990 Attachments smaller than this aren't saved externally. It's also
17991 possible to write a plugin to disable saving specific attachments
17993 Defaults to @samp{128000}.
17996 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
17997 File system backend to use for saving attachments:
18000 No SiS done by Dovecot (but this might help FS's own deduplication)
18002 SiS with immediate byte-by-byte comparison during saving
18003 @item sis-queue posix
18004 SiS with delayed comparison and deduplication.
18006 Defaults to @samp{"sis posix"}.
18009 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
18010 Hash format to use in attachment filenames. You can add any text and
18011 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
18012 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
18013 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
18014 Defaults to @samp{"%@{sha1@}"}.
18017 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
18019 Defaults to @samp{100}.
18022 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
18024 Defaults to @samp{1000}.
18027 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
18028 Default VSZ (virtual memory size) limit for service processes.
18029 This is mainly intended to catch and kill processes that leak memory
18030 before they eat up everything.
18031 Defaults to @samp{256000000}.
18034 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
18035 Login user is internally used by login processes. This is the most
18036 untrusted user in Dovecot system. It shouldn't have access to anything
18038 Defaults to @samp{"dovenull"}.
18041 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
18042 Internal user is used by unprivileged processes. It should be
18043 separate from login user, so that login processes can't disturb other
18045 Defaults to @samp{"dovecot"}.
18048 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
18049 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
18050 Defaults to @samp{"required"}.
18053 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
18054 PEM encoded X.509 SSL/TLS certificate (public key).
18055 Defaults to @samp{"</etc/dovecot/default.pem"}.
18058 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
18059 PEM encoded SSL/TLS private key. The key is opened before
18060 dropping root privileges, so keep the key file unreadable by anyone but
18062 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
18065 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
18066 If key file is password protected, give the password here.
18067 Alternatively give it when starting dovecot with -p parameter. Since
18068 this file is often world-readable, you may want to place this setting
18069 instead to a different.
18070 Defaults to @samp{""}.
18073 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
18074 PEM encoded trusted certificate authority. Set this only if you
18075 intend to use @samp{ssl-verify-client-cert? #t}. The file should
18076 contain the CA certificate(s) followed by the matching
18077 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
18078 Defaults to @samp{""}.
18081 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
18082 Require that CRL check succeeds for client certificates.
18083 Defaults to @samp{#t}.
18086 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
18087 Request client to send a certificate. If you also want to require
18088 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
18089 Defaults to @samp{#f}.
18092 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
18093 Which field from certificate to use for username. commonName and
18094 x500UniqueIdentifier are the usual choices. You'll also need to set
18095 @samp{auth-ssl-username-from-cert? #t}.
18096 Defaults to @samp{"commonName"}.
18099 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
18100 Minimum SSL protocol version to accept.
18101 Defaults to @samp{"TLSv1"}.
18104 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
18105 SSL ciphers to use.
18106 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
18109 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
18110 SSL crypto device to use, for valid values run "openssl engine".
18111 Defaults to @samp{""}.
18114 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
18115 Address to use when sending rejection mails.
18116 %d expands to recipient domain.
18117 Defaults to @samp{"postmaster@@%d"}.
18120 @deftypevr {@code{dovecot-configuration} parameter} string hostname
18121 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
18122 and in LMTP replies. Default is the system's real hostname@@domain.
18123 Defaults to @samp{""}.
18126 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
18127 If user is over quota, return with temporary failure instead of
18129 Defaults to @samp{#f}.
18132 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
18133 Binary to use for sending mails.
18134 Defaults to @samp{"/usr/sbin/sendmail"}.
18137 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
18138 If non-empty, send mails via this SMTP host[:port] instead of
18140 Defaults to @samp{""}.
18143 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
18144 Subject: header to use for rejection mails. You can use the same
18145 variables as for @samp{rejection-reason} below.
18146 Defaults to @samp{"Rejected: %s"}.
18149 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
18150 Human readable error message for rejection mails. You can use
18163 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
18166 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
18167 Delimiter character between local-part and detail in email
18169 Defaults to @samp{"+"}.
18172 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
18173 Header where the original recipient address (SMTP's RCPT TO:
18174 address) is taken from if not available elsewhere. With dovecot-lda -a
18175 parameter overrides this. A commonly used header for this is
18177 Defaults to @samp{""}.
18180 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
18181 Should saving a mail to a nonexistent mailbox automatically create
18183 Defaults to @samp{#f}.
18186 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
18187 Should automatically created mailboxes be also automatically
18189 Defaults to @samp{#f}.
18192 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
18193 Maximum IMAP command line length. Some clients generate very long
18194 command lines with huge mailboxes, so you may need to raise this if you
18195 get "Too long argument" or "IMAP command line too large" errors
18197 Defaults to @samp{64000}.
18200 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
18201 IMAP logout format string:
18204 total number of bytes read from client
18206 total number of bytes sent to client.
18208 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
18209 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@}"}.
18212 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
18213 Override the IMAP CAPABILITY response. If the value begins with '+',
18214 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
18215 Defaults to @samp{""}.
18218 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
18219 How long to wait between "OK Still here" notifications when client
18221 Defaults to @samp{"2 mins"}.
18224 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
18225 ID field names and values to send to clients. Using * as the value
18226 makes Dovecot use the default value. The following fields have default
18227 values currently: name, version, os, os-version, support-url,
18229 Defaults to @samp{""}.
18232 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
18233 ID fields sent by client to log. * means everything.
18234 Defaults to @samp{""}.
18237 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
18238 Workarounds for various client bugs:
18241 @item delay-newmail
18242 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
18243 CHECK commands. Some clients ignore them otherwise, for example OSX
18244 Mail (<v2.1). Outlook Express breaks more badly though, without this it
18245 may show user "Message no longer in server" errors. Note that OE6
18246 still breaks even with this workaround if synchronization is set to
18249 @item tb-extra-mailbox-sep
18250 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
18251 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
18252 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
18254 @item tb-lsub-flags
18255 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
18256 This makes Thunderbird realize they aren't selectable and show them
18257 greyed out, instead of only later giving "not selectable" popup error.
18259 Defaults to @samp{()}.
18262 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
18263 Host allowed in URLAUTH URLs sent by client. "*" allows all.
18264 Defaults to @samp{""}.
18268 Whew! Lots of configuration options. The nice thing about it though is
18269 that Guix has a complete interface to Dovecot's configuration
18270 language. This allows not only a nice way to declare configurations,
18271 but also offers reflective capabilities as well: users can write code to
18272 inspect and transform configurations from within Scheme.
18274 However, it could be that you just want to get a @code{dovecot.conf} up
18275 and running. In that case, you can pass an
18276 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
18277 @code{dovecot-service}. As its name indicates, an opaque configuration
18278 does not have easy reflective capabilities.
18280 Available @code{opaque-dovecot-configuration} fields are:
18282 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
18283 The dovecot package.
18286 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
18287 The contents of the @code{dovecot.conf}, as a string.
18290 For example, if your @code{dovecot.conf} is just the empty string, you
18291 could instantiate a dovecot service like this:
18294 (dovecot-service #:config
18295 (opaque-dovecot-configuration
18299 @subsubheading OpenSMTPD Service
18301 @deffn {Scheme Variable} opensmtpd-service-type
18302 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
18303 service, whose value should be an @code{opensmtpd-configuration} object
18304 as in this example:
18307 (service opensmtpd-service-type
18308 (opensmtpd-configuration
18309 (config-file (local-file "./my-smtpd.conf"))))
18313 @deftp {Data Type} opensmtpd-configuration
18314 Data type representing the configuration of opensmtpd.
18317 @item @code{package} (default: @var{opensmtpd})
18318 Package object of the OpenSMTPD SMTP server.
18320 @item @code{config-file} (default: @code{%default-opensmtpd-file})
18321 File-like object of the OpenSMTPD configuration file to use. By default
18322 it listens on the loopback network interface, and allows for mail from
18323 users and daemons on the local machine, as well as permitting email to
18324 remote servers. Run @command{man smtpd.conf} for more information.
18329 @subsubheading Exim Service
18331 @cindex mail transfer agent (MTA)
18332 @cindex MTA (mail transfer agent)
18335 @deffn {Scheme Variable} exim-service-type
18336 This is the type of the @uref{https://exim.org, Exim} mail transfer
18337 agent (MTA), whose value should be an @code{exim-configuration} object
18338 as in this example:
18341 (service exim-service-type
18342 (exim-configuration
18343 (config-file (local-file "./my-exim.conf"))))
18347 In order to use an @code{exim-service-type} service you must also have a
18348 @code{mail-aliases-service-type} service present in your
18349 @code{operating-system} (even if it has no aliases).
18351 @deftp {Data Type} exim-configuration
18352 Data type representing the configuration of exim.
18355 @item @code{package} (default: @var{exim})
18356 Package object of the Exim server.
18358 @item @code{config-file} (default: @code{#f})
18359 File-like object of the Exim configuration file to use. If its value is
18360 @code{#f} then use the default configuration file from the package
18361 provided in @code{package}. The resulting configuration file is loaded
18362 after setting the @code{exim_user} and @code{exim_group} configuration
18368 @subsubheading Getmail service
18373 @deffn {Scheme Variable} getmail-service-type
18374 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
18375 mail retriever, whose value should be an @code{getmail-configuration}.
18378 Available @code{getmail-configuration} fields are:
18380 @deftypevr {@code{getmail-configuration} parameter} symbol name
18381 A symbol to identify the getmail service.
18383 Defaults to @samp{"unset"}.
18387 @deftypevr {@code{getmail-configuration} parameter} package package
18388 The getmail package to use.
18392 @deftypevr {@code{getmail-configuration} parameter} string user
18393 The user to run getmail as.
18395 Defaults to @samp{"getmail"}.
18399 @deftypevr {@code{getmail-configuration} parameter} string group
18400 The group to run getmail as.
18402 Defaults to @samp{"getmail"}.
18406 @deftypevr {@code{getmail-configuration} parameter} string directory
18407 The getmail directory to use.
18409 Defaults to @samp{"/var/lib/getmail/default"}.
18413 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
18414 The getmail configuration file to use.
18416 Available @code{getmail-configuration-file} fields are:
18418 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
18419 What mail account to retrieve mail from, and how to access that account.
18421 Available @code{getmail-retriever-configuration} fields are:
18423 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
18424 The type of mail retriever to use. Valid values include @samp{passwd}
18427 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
18431 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
18432 Username to login to the mail server with.
18434 Defaults to @samp{unset}.
18438 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
18439 Username to login to the mail server with.
18441 Defaults to @samp{unset}.
18445 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
18446 Port number to connect to.
18448 Defaults to @samp{#f}.
18452 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
18453 Override fields from passwd.
18455 Defaults to @samp{""}.
18459 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
18460 Override fields from passwd.
18462 Defaults to @samp{()}.
18466 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
18467 PEM-formatted key file to use for the TLS negotiation.
18469 Defaults to @samp{""}.
18473 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
18474 PEM-formatted certificate file to use for the TLS negotiation.
18476 Defaults to @samp{""}.
18480 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
18481 CA certificates to use.
18483 Defaults to @samp{""}.
18487 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
18488 Extra retriever parameters.
18490 Defaults to @samp{()}.
18496 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
18497 What to do with retrieved messages.
18499 Available @code{getmail-destination-configuration} fields are:
18501 @deftypevr {@code{getmail-destination-configuration} parameter} string type
18502 The type of mail destination. Valid values include @samp{Maildir},
18503 @samp{Mboxrd} and @samp{MDA_external}.
18505 Defaults to @samp{unset}.
18509 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
18510 The path option for the mail destination. The behaviour depends on the
18513 Defaults to @samp{""}.
18517 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
18518 Extra destination parameters
18520 Defaults to @samp{()}.
18526 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
18529 Available @code{getmail-options-configuration} fields are:
18531 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
18532 If set to @samp{0}, getmail will only print warnings and errors. A
18533 value of @samp{1} means that messages will be printed about retrieving
18534 and deleting messages. If set to @samp{2}, getmail will print messages
18535 about each of it's actions.
18537 Defaults to @samp{1}.
18541 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
18542 If true, getmail will retrieve all available messages. Otherwise it
18543 will only retrieve messages it hasn't seen previously.
18545 Defaults to @samp{#t}.
18549 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
18550 If set to true, messages will be deleted from the server after
18551 retrieving and successfully delivering them. Otherwise, messages will
18552 be left on the server.
18554 Defaults to @samp{#f}.
18558 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
18559 Getmail will delete messages this number of days after seeing them, if
18560 they have been delivered. This means messages will be left on the
18561 server this number of days after delivering them. A value of @samp{0}
18562 disabled this feature.
18564 Defaults to @samp{0}.
18568 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
18569 Delete messages larger than this of bytes after retrieving them, even if
18570 the delete and delete-after options are disabled. A value of @samp{0}
18571 disables this feature.
18573 Defaults to @samp{0}.
18577 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
18578 Retrieve messages totalling up to this number of bytes before closing
18579 the session with the server. A value of @samp{0} disables this feature.
18581 Defaults to @samp{0}.
18585 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
18586 Don't retrieve messages larger than this number of bytes. A value of
18587 @samp{0} disables this feature.
18589 Defaults to @samp{0}.
18593 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
18594 If true, getmail will add a Delivered-To header to messages.
18596 Defaults to @samp{#t}.
18600 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
18601 If set, getmail adds a Received header to the messages.
18603 Defaults to @samp{#t}.
18607 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
18608 Getmail will record a log of its actions to the named file. A value of
18609 @samp{""} disables this feature.
18611 Defaults to @samp{""}.
18615 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
18616 If true, getmail will record a log of its actions using the system
18619 Defaults to @samp{#f}.
18623 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
18624 If true, getmail will log information about messages not retrieved and
18625 the reason for not retrieving them, as well as starting and ending
18628 Defaults to @samp{#f}.
18632 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
18633 Extra options to include.
18635 Defaults to @samp{()}.
18643 @deftypevr {@code{getmail-configuration} parameter} list idle
18644 A list of mailboxes that getmail should wait on the server for new mail
18645 notifications. This depends on the server supporting the IDLE
18648 Defaults to @samp{()}.
18652 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
18653 Environment variables to set for getmail.
18655 Defaults to @samp{()}.
18659 @subsubheading Mail Aliases Service
18661 @cindex email aliases
18662 @cindex aliases, for email addresses
18664 @deffn {Scheme Variable} mail-aliases-service-type
18665 This is the type of the service which provides @code{/etc/aliases},
18666 specifying how to deliver mail to users on this system.
18669 (service mail-aliases-service-type
18670 '(("postmaster" "bob")
18671 ("bob" "bob@@example.com" "bob@@example2.com")))
18675 The configuration for a @code{mail-aliases-service-type} service is an
18676 association list denoting how to deliver mail that comes to this
18677 system. Each entry is of the form @code{(alias addresses ...)}, with
18678 @code{alias} specifying the local alias and @code{addresses} specifying
18679 where to deliver this user's mail.
18681 The aliases aren't required to exist as users on the local system. In
18682 the above example, there doesn't need to be a @code{postmaster} entry in
18683 the @code{operating-system}'s @code{user-accounts} in order to deliver
18684 the @code{postmaster} mail to @code{bob} (which subsequently would
18685 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
18687 @subsubheading GNU Mailutils IMAP4 Daemon
18688 @cindex GNU Mailutils IMAP4 Daemon
18690 @deffn {Scheme Variable} imap4d-service-type
18691 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
18692 mailutils, GNU Mailutils Manual}), whose value should be an
18693 @code{imap4d-configuration} object as in this example:
18696 (service imap4d-service-type
18697 (imap4d-configuration
18698 (config-file (local-file "imap4d.conf"))))
18702 @deftp {Data Type} imap4d-configuration
18703 Data type representing the configuration of @command{imap4d}.
18706 @item @code{package} (default: @code{mailutils})
18707 The package that provides @command{imap4d}.
18709 @item @code{config-file} (default: @code{%default-imap4d-config-file})
18710 File-like object of the configuration file to use, by default it will listen
18711 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
18712 Mailutils Manual}, for details.
18717 @node Messaging Services
18718 @subsection Messaging Services
18723 The @code{(gnu services messaging)} module provides Guix service
18724 definitions for messaging services: currently only Prosody is supported.
18726 @subsubheading Prosody Service
18728 @deffn {Scheme Variable} prosody-service-type
18729 This is the type for the @uref{https://prosody.im, Prosody XMPP
18730 communication server}. Its value must be a @code{prosody-configuration}
18731 record as in this example:
18734 (service prosody-service-type
18735 (prosody-configuration
18736 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
18739 (int-component-configuration
18740 (hostname "conference.example.net")
18742 (mod-muc (mod-muc-configuration)))))
18745 (virtualhost-configuration
18746 (domain "example.net"))))))
18749 See below for details about @code{prosody-configuration}.
18753 By default, Prosody does not need much configuration. Only one
18754 @code{virtualhosts} field is needed: it specifies the domain you wish
18757 You can perform various sanity checks on the generated configuration
18758 with the @code{prosodyctl check} command.
18760 Prosodyctl will also help you to import certificates from the
18761 @code{letsencrypt} directory so that the @code{prosody} user can access
18762 them. See @url{https://prosody.im/doc/letsencrypt}.
18765 prosodyctl --root cert import /etc/letsencrypt/live
18768 The available configuration parameters follow. Each parameter
18769 definition is preceded by its type; for example, @samp{string-list foo}
18770 indicates that the @code{foo} parameter should be specified as a list of
18771 strings. Types starting with @code{maybe-} denote parameters that won't
18772 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
18774 There is also a way to specify the configuration as a string, if you
18775 have an old @code{prosody.cfg.lua} file that you want to port over from
18776 some other system; see the end for more details.
18778 The @code{file-object} type designates either a file-like object
18779 (@pxref{G-Expressions, file-like objects}) or a file name.
18781 @c The following documentation was initially generated by
18782 @c (generate-documentation) in (gnu services messaging). Manually maintained
18783 @c documentation is better, so we shouldn't hesitate to edit below as
18784 @c needed. However if the change you want to make to this documentation
18785 @c can be done in an automated way, it's probably easier to change
18786 @c (generate-documentation) than to make it below and have to deal with
18787 @c the churn as Prosody updates.
18789 Available @code{prosody-configuration} fields are:
18791 @deftypevr {@code{prosody-configuration} parameter} package prosody
18792 The Prosody package.
18795 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
18796 Location of the Prosody data storage directory. See
18797 @url{https://prosody.im/doc/configure}.
18798 Defaults to @samp{"/var/lib/prosody"}.
18801 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
18802 Additional plugin directories. They are searched in all the specified
18803 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
18804 Defaults to @samp{()}.
18807 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
18808 Every virtual host and component needs a certificate so that clients and
18809 servers can securely verify its identity. Prosody will automatically load
18810 certificates/keys from the directory specified here.
18811 Defaults to @samp{"/etc/prosody/certs"}.
18814 @deftypevr {@code{prosody-configuration} parameter} string-list admins
18815 This is a list of accounts that are admins for the server. Note that you
18816 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
18817 @url{https://prosody.im/doc/creating_accounts}.
18818 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
18819 Defaults to @samp{()}.
18822 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
18823 Enable use of libevent for better performance under high load. See
18824 @url{https://prosody.im/doc/libevent}.
18825 Defaults to @samp{#f}.
18828 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
18829 This is the list of modules Prosody will load on startup. It looks for
18830 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
18831 Documentation on modules can be found at:
18832 @url{https://prosody.im/doc/modules}.
18833 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
18836 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
18837 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
18838 should you want to disable them then add them to this list.
18839 Defaults to @samp{()}.
18842 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
18843 Path to a text file where the shared groups are defined. If this path is
18844 empty then @samp{mod_groups} does nothing. See
18845 @url{https://prosody.im/doc/modules/mod_groups}.
18846 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
18849 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
18850 Disable account creation by default, for security. See
18851 @url{https://prosody.im/doc/creating_accounts}.
18852 Defaults to @samp{#f}.
18855 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
18856 These are the SSL/TLS-related settings. Most of them are disabled so to
18857 use Prosody's defaults. If you do not completely understand these options, do
18858 not add them to your config, it is easy to lower the security of your server
18859 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
18861 Available @code{ssl-configuration} fields are:
18863 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
18864 This determines what handshake to use.
18867 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
18868 Path to your private key file.
18871 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
18872 Path to your certificate file.
18875 @deftypevr {@code{ssl-configuration} parameter} file-object capath
18876 Path to directory containing root certificates that you wish Prosody to
18877 trust when verifying the certificates of remote servers.
18878 Defaults to @samp{"/etc/ssl/certs"}.
18881 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
18882 Path to a file containing root certificates that you wish Prosody to trust.
18883 Similar to @code{capath} but with all certificates concatenated together.
18886 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
18887 A list of verification options (these mostly map to OpenSSL's
18888 @code{set_verify()} flags).
18891 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
18892 A list of general options relating to SSL/TLS. These map to OpenSSL's
18893 @code{set_options()}. For a full list of options available in LuaSec, see the
18897 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
18898 How long a chain of certificate authorities to check when looking for a
18899 trusted root certificate.
18902 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
18903 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
18904 clients, and in what order.
18907 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
18908 A path to a file containing parameters for Diffie-Hellman key exchange. You
18909 can create such a file with:
18910 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
18913 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
18914 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
18915 @samp{"secp384r1"}.
18918 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
18919 A list of ``extra'' verification options.
18922 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
18923 Password for encrypted private keys.
18928 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
18929 Whether to force all client-to-server connections to be encrypted or not.
18930 See @url{https://prosody.im/doc/modules/mod_tls}.
18931 Defaults to @samp{#f}.
18934 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
18935 Set of mechanisms that will never be offered. See
18936 @url{https://prosody.im/doc/modules/mod_saslauth}.
18937 Defaults to @samp{("DIGEST-MD5")}.
18940 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
18941 Whether to force all server-to-server connections to be encrypted or not.
18942 See @url{https://prosody.im/doc/modules/mod_tls}.
18943 Defaults to @samp{#f}.
18946 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
18947 Whether to require encryption and certificate authentication. This
18948 provides ideal security, but requires servers you communicate with to support
18949 encryption AND present valid, trusted certificates. See
18950 @url{https://prosody.im/doc/s2s#security}.
18951 Defaults to @samp{#f}.
18954 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
18955 Many servers don't support encryption or have invalid or self-signed
18956 certificates. You can list domains here that will not be required to
18957 authenticate using certificates. They will be authenticated using DNS. See
18958 @url{https://prosody.im/doc/s2s#security}.
18959 Defaults to @samp{()}.
18962 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
18963 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
18964 valid certificates for some domains by specifying a list here. See
18965 @url{https://prosody.im/doc/s2s#security}.
18966 Defaults to @samp{()}.
18969 @deftypevr {@code{prosody-configuration} parameter} string authentication
18970 Select the authentication backend to use. The default provider stores
18971 passwords in plaintext and uses Prosody's configured data storage to store the
18972 authentication data. If you do not trust your server please see
18973 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
18974 about using the hashed backend. See also
18975 @url{https://prosody.im/doc/authentication}
18976 Defaults to @samp{"internal_plain"}.
18979 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
18980 Set logging options. Advanced logging configuration is not yet supported
18981 by the Prosody service. See @url{https://prosody.im/doc/logging}.
18982 Defaults to @samp{"*syslog"}.
18985 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
18986 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
18987 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
18990 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
18991 Maximum allowed size of the HTTP body (in bytes).
18994 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
18995 Some modules expose their own URL in various ways. This URL is built
18996 from the protocol, host and port used. If Prosody sits behind a proxy, the
18997 public URL will be @code{http-external-url} instead. See
18998 @url{https://prosody.im/doc/http#external_url}.
19001 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
19002 A host in Prosody is a domain on which user accounts can be created. For
19003 example if you want your users to have addresses like
19004 @samp{"john.smith@@example.com"} then you need to add a host
19005 @samp{"example.com"}. All options in this list will apply only to this host.
19007 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
19008 the actual physical host that Prosody is installed on. A single Prosody
19009 instance can serve many domains, each one defined as a VirtualHost entry in
19010 Prosody's configuration. Conversely a server that hosts a single domain would
19011 have just one VirtualHost entry.
19013 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
19015 Available @code{virtualhost-configuration} fields are:
19017 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:
19018 @deftypevr {@code{virtualhost-configuration} parameter} string domain
19019 Domain you wish Prosody to serve.
19024 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
19025 Components are extra services on a server which are available to clients,
19026 usually on a subdomain of the main server (such as
19027 @samp{"mycomponent.example.com"}). Example components might be chatroom
19028 servers, user directories, or gateways to other protocols.
19030 Internal components are implemented with Prosody-specific plugins. To add an
19031 internal component, you simply fill the hostname field, and the plugin you wish
19032 to use for the component.
19034 See @url{https://prosody.im/doc/components}.
19035 Defaults to @samp{()}.
19037 Available @code{int-component-configuration} fields are:
19039 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:
19040 @deftypevr {@code{int-component-configuration} parameter} string hostname
19041 Hostname of the component.
19044 @deftypevr {@code{int-component-configuration} parameter} string plugin
19045 Plugin you wish to use for the component.
19048 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
19049 Multi-user chat (MUC) is Prosody's module for allowing you to create
19050 hosted chatrooms/conferences for XMPP users.
19052 General information on setting up and using multi-user chatrooms can be found
19053 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
19054 which you should read if you are new to XMPP chatrooms.
19056 See also @url{https://prosody.im/doc/modules/mod_muc}.
19058 Available @code{mod-muc-configuration} fields are:
19060 @deftypevr {@code{mod-muc-configuration} parameter} string name
19061 The name to return in service discovery responses.
19062 Defaults to @samp{"Prosody Chatrooms"}.
19065 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
19066 If @samp{#t}, this will only allow admins to create new chatrooms.
19067 Otherwise anyone can create a room. The value @samp{"local"} restricts room
19068 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
19069 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
19070 restricts to service administrators only.
19071 Defaults to @samp{#f}.
19074 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
19075 Maximum number of history messages that will be sent to the member that has
19076 just joined the room.
19077 Defaults to @samp{20}.
19084 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
19085 External components use XEP-0114, which most standalone components
19086 support. To add an external component, you simply fill the hostname field. See
19087 @url{https://prosody.im/doc/components}.
19088 Defaults to @samp{()}.
19090 Available @code{ext-component-configuration} fields are:
19092 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:
19093 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
19094 Password which the component will use to log in.
19097 @deftypevr {@code{ext-component-configuration} parameter} string hostname
19098 Hostname of the component.
19103 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
19104 Port(s) Prosody listens on for component connections.
19105 Defaults to @samp{(5347)}.
19108 @deftypevr {@code{prosody-configuration} parameter} string component-interface
19109 Interface Prosody listens on for component connections.
19110 Defaults to @samp{"127.0.0.1"}.
19113 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
19114 Raw content that will be added to the configuration file.
19117 It could be that you just want to get a @code{prosody.cfg.lua}
19118 up and running. In that case, you can pass an
19119 @code{opaque-prosody-configuration} record as the value of
19120 @code{prosody-service-type}. As its name indicates, an opaque configuration
19121 does not have easy reflective capabilities.
19122 Available @code{opaque-prosody-configuration} fields are:
19124 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
19125 The prosody package.
19128 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
19129 The contents of the @code{prosody.cfg.lua} to use.
19132 For example, if your @code{prosody.cfg.lua} is just the empty
19133 string, you could instantiate a prosody service like this:
19136 (service prosody-service-type
19137 (opaque-prosody-configuration
19138 (prosody.cfg.lua "")))
19141 @c end of Prosody auto-generated documentation
19143 @subsubheading BitlBee Service
19145 @cindex IRC (Internet Relay Chat)
19146 @cindex IRC gateway
19147 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
19148 interface to a variety of messaging protocols such as XMPP.
19150 @defvr {Scheme Variable} bitlbee-service-type
19151 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
19152 gateway daemon. Its value is a @code{bitlbee-configuration} (see
19155 To have BitlBee listen on port 6667 on localhost, add this line to your
19159 (service bitlbee-service-type)
19163 @deftp {Data Type} bitlbee-configuration
19164 This is the configuration for BitlBee, with the following fields:
19167 @item @code{interface} (default: @code{"127.0.0.1"})
19168 @itemx @code{port} (default: @code{6667})
19169 Listen on the network interface corresponding to the IP address
19170 specified in @var{interface}, on @var{port}.
19172 When @var{interface} is @code{127.0.0.1}, only local clients can
19173 connect; when it is @code{0.0.0.0}, connections can come from any
19174 networking interface.
19176 @item @code{bitlbee} (default: @code{bitlbee})
19177 The BitlBee package to use.
19179 @item @code{plugins} (default: @code{'()})
19180 List of plugin packages to use---e.g., @code{bitlbee-discord}.
19182 @item @code{extra-settings} (default: @code{""})
19183 Configuration snippet added as-is to the BitlBee configuration file.
19187 @subsubheading Quassel Service
19189 @cindex IRC (Internet Relay Chat)
19190 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
19191 meaning that one or more clients can attach to and detach from the
19194 @defvr {Scheme Variable} quassel-service-type
19195 This is the service type for the @url{https://quassel-irc.org/,Quassel}
19196 IRC backend daemon. Its value is a @code{quassel-configuration}
19200 @deftp {Data Type} quassel-configuration
19201 This is the configuration for Quassel, with the following fields:
19204 @item @code{quassel} (default: @code{quassel})
19205 The Quassel package to use.
19207 @item @code{interface} (default: @code{"::,0.0.0.0"})
19208 @item @code{port} (default: @code{4242})
19209 Listen on the network interface(s) corresponding to the IPv4 or IPv6
19210 interfaces specified in the comma delimited @var{interface}, on
19213 @item @code{loglevel} (default: @code{"Info"})
19214 The level of logging desired. Accepted values are Debug, Info, Warning
19219 @node Telephony Services
19220 @subsection Telephony Services
19222 @cindex Murmur (VoIP server)
19223 @cindex VoIP server
19224 This section describes how to set up and run a Murmur server. Murmur is
19225 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
19228 @deftp {Data Type} murmur-configuration
19229 The service type for the Murmur server. An example configuration can
19233 (service murmur-service-type
19234 (murmur-configuration
19236 "Welcome to this Mumble server running on Guix!")
19237 (cert-required? #t) ;disallow text password logins
19238 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
19239 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
19242 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
19243 password with the command that is printed during the activation phase.
19245 It is recommended to register a normal Mumble user account
19246 and grant it admin or moderator rights.
19247 You can use the @code{mumble} client to
19248 login as new normal user, register yourself, and log out.
19249 For the next step login with the name @code{SuperUser} use
19250 the @code{SuperUser} password that you set previously,
19251 and grant your newly registered mumble user administrator or moderator
19252 rights and create some channels.
19254 Available @code{murmur-configuration} fields are:
19257 @item @code{package} (default: @code{mumble})
19258 Package that contains @code{bin/murmurd}.
19260 @item @code{user} (default: @code{"murmur"})
19261 User who will run the Murmur server.
19263 @item @code{group} (default: @code{"murmur"})
19264 Group of the user who will run the murmur server.
19266 @item @code{port} (default: @code{64738})
19267 Port on which the server will listen.
19269 @item @code{welcome-text} (default: @code{""})
19270 Welcome text sent to clients when they connect.
19272 @item @code{server-password} (default: @code{""})
19273 Password the clients have to enter in order to connect.
19275 @item @code{max-users} (default: @code{100})
19276 Maximum of users that can be connected to the server at once.
19278 @item @code{max-user-bandwidth} (default: @code{#f})
19279 Maximum voice traffic a user can send per second.
19281 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
19282 File name of the sqlite database.
19283 The service's user will become the owner of the directory.
19285 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
19286 File name of the log file.
19287 The service's user will become the owner of the directory.
19289 @item @code{autoban-attempts} (default: @code{10})
19290 Maximum number of logins a user can make in @code{autoban-timeframe}
19291 without getting auto banned for @code{autoban-time}.
19293 @item @code{autoban-timeframe} (default: @code{120})
19294 Timeframe for autoban in seconds.
19296 @item @code{autoban-time} (default: @code{300})
19297 Amount of time in seconds for which a client gets banned
19298 when violating the autoban limits.
19300 @item @code{opus-threshold} (default: @code{100})
19301 Percentage of clients that need to support opus
19302 before switching over to opus audio codec.
19304 @item @code{channel-nesting-limit} (default: @code{10})
19305 How deep channels can be nested at maximum.
19307 @item @code{channelname-regex} (default: @code{#f})
19308 A string in form of a Qt regular expression that channel names must conform to.
19310 @item @code{username-regex} (default: @code{#f})
19311 A string in form of a Qt regular expression that user names must conform to.
19313 @item @code{text-message-length} (default: @code{5000})
19314 Maximum size in bytes that a user can send in one text chat message.
19316 @item @code{image-message-length} (default: @code{(* 128 1024)})
19317 Maximum size in bytes that a user can send in one image message.
19319 @item @code{cert-required?} (default: @code{#f})
19320 If it is set to @code{#t} clients that use weak password authentication
19321 will not be accepted. Users must have completed the certificate wizard to join.
19323 @item @code{remember-channel?} (default: @code{#f})
19324 Should murmur remember the last channel each user was in when they disconnected
19325 and put them into the remembered channel when they rejoin.
19327 @item @code{allow-html?} (default: @code{#f})
19328 Should html be allowed in text messages, user comments, and channel descriptions.
19330 @item @code{allow-ping?} (default: @code{#f})
19331 Setting to true exposes the current user count, the maximum user count, and
19332 the server's maximum bandwidth per client to unauthenticated users. In the
19333 Mumble client, this information is shown in the Connect dialog.
19335 Disabling this setting will prevent public listing of the server.
19337 @item @code{bonjour?} (default: @code{#f})
19338 Should the server advertise itself in the local network through the bonjour protocol.
19340 @item @code{send-version?} (default: @code{#f})
19341 Should the murmur server version be exposed in ping requests.
19343 @item @code{log-days} (default: @code{31})
19344 Murmur also stores logs in the database, which are accessible via RPC.
19345 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
19346 or -1 to disable logging to the database.
19348 @item @code{obfuscate-ips?} (default: @code{#t})
19349 Should logged ips be obfuscated to protect the privacy of users.
19351 @item @code{ssl-cert} (default: @code{#f})
19352 File name of the SSL/TLS certificate used for encrypted connections.
19355 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
19357 @item @code{ssl-key} (default: @code{#f})
19358 Filepath to the ssl private key used for encrypted connections.
19360 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
19363 @item @code{ssl-dh-params} (default: @code{#f})
19364 File name of a PEM-encoded file with Diffie-Hellman parameters
19365 for the SSL/TLS encryption. Alternatively you set it to
19366 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
19367 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
19369 @item @code{ssl-ciphers} (default: @code{#f})
19370 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
19373 This option is specified using
19374 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
19375 OpenSSL cipher list notation}.
19377 It is recommended that you try your cipher string using 'openssl ciphers <string>'
19378 before setting it here, to get a feel for which cipher suites you will get.
19379 After setting this option, it is recommend that you inspect your Murmur log
19380 to ensure that Murmur is using the cipher suites that you expected it to.
19382 Note: Changing this option may impact the backwards compatibility of your
19383 Murmur server, and can remove the ability for older Mumble clients to be able
19386 @item @code{public-registration} (default: @code{#f})
19387 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
19389 You can optionally register your server in the public server list that the
19390 @code{mumble} client shows on startup.
19391 You cannot register your server if you have set a @code{server-password},
19392 or set @code{allow-ping} to @code{#f}.
19394 It might take a few hours until it shows up in the public list.
19396 @item @code{file} (default: @code{#f})
19397 Optional alternative override for this configuration.
19401 @deftp {Data Type} murmur-public-registration-configuration
19402 Configuration for public registration of a murmur service.
19406 This is a display name for your server. Not to be confused with the hostname.
19408 @item @code{password}
19409 A password to identify your registration.
19410 Subsequent updates will need the same password. Don't lose your password.
19413 This should be a @code{http://} or @code{https://} link to your web
19416 @item @code{hostname} (default: @code{#f})
19417 By default your server will be listed by its IP address.
19418 If it is set your server will be linked by this host name instead.
19424 @node Monitoring Services
19425 @subsection Monitoring Services
19427 @subsubheading Tailon Service
19429 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
19430 viewing and searching log files.
19432 The following example will configure the service with default values.
19433 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
19436 (service tailon-service-type)
19439 The following example customises more of the Tailon configuration,
19440 adding @command{sed} to the list of allowed commands.
19443 (service tailon-service-type
19444 (tailon-configuration
19446 (tailon-configuration-file
19447 (allowed-commands '("tail" "grep" "awk" "sed"))))))
19451 @deftp {Data Type} tailon-configuration
19452 Data type representing the configuration of Tailon.
19453 This type has the following parameters:
19456 @item @code{config-file} (default: @code{(tailon-configuration-file)})
19457 The configuration file to use for Tailon. This can be set to a
19458 @dfn{tailon-configuration-file} record value, or any gexp
19459 (@pxref{G-Expressions}).
19461 For example, to instead use a local file, the @code{local-file} function
19465 (service tailon-service-type
19466 (tailon-configuration
19467 (config-file (local-file "./my-tailon.conf"))))
19470 @item @code{package} (default: @code{tailon})
19471 The tailon package to use.
19476 @deftp {Data Type} tailon-configuration-file
19477 Data type representing the configuration options for Tailon.
19478 This type has the following parameters:
19481 @item @code{files} (default: @code{(list "/var/log")})
19482 List of files to display. The list can include strings for a single file
19483 or directory, or a list, where the first item is the name of a
19484 subsection, and the remaining items are the files or directories in that
19487 @item @code{bind} (default: @code{"localhost:8080"})
19488 Address and port to which Tailon should bind on.
19490 @item @code{relative-root} (default: @code{#f})
19491 URL path to use for Tailon, set to @code{#f} to not use a path.
19493 @item @code{allow-transfers?} (default: @code{#t})
19494 Allow downloading the log files in the web interface.
19496 @item @code{follow-names?} (default: @code{#t})
19497 Allow tailing of not-yet existent files.
19499 @item @code{tail-lines} (default: @code{200})
19500 Number of lines to read initially from each file.
19502 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
19503 Commands to allow running. By default, @code{sed} is disabled.
19505 @item @code{debug?} (default: @code{#f})
19506 Set @code{debug?} to @code{#t} to show debug messages.
19508 @item @code{wrap-lines} (default: @code{#t})
19509 Initial line wrapping state in the web interface. Set to @code{#t} to
19510 initially wrap lines (the default), or to @code{#f} to initially not
19513 @item @code{http-auth} (default: @code{#f})
19514 HTTP authentication type to use. Set to @code{#f} to disable
19515 authentication (the default). Supported values are @code{"digest"} or
19518 @item @code{users} (default: @code{#f})
19519 If HTTP authentication is enabled (see @code{http-auth}), access will be
19520 restricted to the credentials provided here. To configure users, use a
19521 list of pairs, where the first element of the pair is the username, and
19522 the 2nd element of the pair is the password.
19525 (tailon-configuration-file
19526 (http-auth "basic")
19527 (users '(("user1" . "password1")
19528 ("user2" . "password2"))))
19535 @subsubheading Darkstat Service
19537 Darkstat is a packet sniffer that captures network traffic, calculates
19538 statistics about usage, and serves reports over HTTP.
19540 @defvar {Scheme Variable} darkstat-service-type
19541 This is the service type for the
19542 @uref{https://unix4lyfe.org/darkstat/, darkstat}
19543 service, its value must be a @code{darkstat-configuration} record as in
19547 (service darkstat-service-type
19548 (darkstat-configuration
19549 (interface "eno1")))
19553 @deftp {Data Type} darkstat-configuration
19554 Data type representing the configuration of @command{darkstat}.
19557 @item @code{package} (default: @code{darkstat})
19558 The darkstat package to use.
19560 @item @code{interface}
19561 Capture traffic on the specified network interface.
19563 @item @code{port} (default: @code{"667"})
19564 Bind the web interface to the specified port.
19566 @item @code{bind-address} (default: @code{"127.0.0.1"})
19567 Bind the web interface to the specified address.
19569 @item @code{base} (default: @code{"/"})
19570 Specify the path of the base URL. This can be useful if
19571 @command{darkstat} is accessed via a reverse proxy.
19576 @subsubheading Prometheus Node Exporter Service
19578 @cindex prometheus-node-exporter
19579 The Prometheus ``node exporter'' makes hardware and operating system statistics
19580 provided by the Linux kernel available for the Prometheus monitoring system.
19581 This service should be deployed on all physical nodes and virtual machines,
19582 where monitoring these statistics is desirable.
19584 @defvar {Scheme variable} prometheus-node-exporter-service-type
19585 This is the service type for the
19586 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
19587 service, its value must be a @code{prometheus-node-exporter-configuration}
19588 record as in this example:
19591 (service prometheus-node-exporter-service-type
19592 (prometheus-node-exporter-configuration
19593 (web-listen-address ":9100")))
19597 @deftp {Data Type} prometheus-node-exporter-configuration
19598 Data type representing the configuration of @command{node_exporter}.
19601 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
19602 The prometheus-node-exporter package to use.
19604 @item @code{web-listen-address} (default: @code{":9100"})
19605 Bind the web interface to the specified address.
19610 @subsubheading Zabbix server
19611 @cindex zabbix zabbix-server
19612 Zabbix provides monitoring metrics, among others network utilization, CPU load
19613 and disk space consumption:
19616 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
19617 @item Auto-discovery of servers and network devices and interfaces.
19618 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
19619 @item Distributed monitoring with centralized web administration.
19620 @item Native high performance agents.
19621 @item SLA, and ITIL KPI metrics on reporting.
19622 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
19623 @item Remote command execution through Zabbix proxies.
19626 @c %start of fragment
19628 Available @code{zabbix-server-configuration} fields are:
19630 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
19631 The zabbix-server package.
19635 @deftypevr {@code{zabbix-server-configuration} parameter} string user
19636 User who will run the Zabbix server.
19638 Defaults to @samp{"zabbix"}.
19642 @deftypevr {@code{zabbix-server-configuration} parameter} group group
19643 Group who will run the Zabbix server.
19645 Defaults to @samp{"zabbix"}.
19649 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
19650 Database host name.
19652 Defaults to @samp{"127.0.0.1"}.
19656 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
19659 Defaults to @samp{"zabbix"}.
19663 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
19666 Defaults to @samp{"zabbix"}.
19670 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
19671 Database password. Please, use @code{include-files} with
19672 @code{DBPassword=SECRET} inside a specified file instead.
19674 Defaults to @samp{""}.
19678 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
19681 Defaults to @samp{5432}.
19685 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
19686 Specifies where log messages are written to:
19690 @code{system} - syslog.
19693 @code{file} - file specified with @code{log-file} parameter.
19696 @code{console} - standard output.
19700 Defaults to @samp{""}.
19704 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
19705 Log file name for @code{log-type} @code{file} parameter.
19707 Defaults to @samp{"/var/log/zabbix/server.log"}.
19711 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
19714 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
19718 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
19719 The location of certificate authority (CA) files for SSL server
19720 certificate verification.
19722 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
19726 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
19727 Location of SSL client certificates.
19729 Defaults to @samp{"/etc/ssl/certs"}.
19733 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
19734 Extra options will be appended to Zabbix server configuration file.
19736 Defaults to @samp{""}.
19740 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
19741 You may include individual files or all files in a directory in the
19742 configuration file.
19744 Defaults to @samp{()}.
19748 @c %end of fragment
19750 @subsubheading Zabbix agent
19751 @cindex zabbix zabbix-agent
19753 Zabbix agent gathers information for Zabbix server.
19755 @c %start of fragment
19757 Available @code{zabbix-agent-configuration} fields are:
19759 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
19760 The zabbix-agent package.
19764 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
19765 User who will run the Zabbix agent.
19767 Defaults to @samp{"zabbix"}.
19771 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
19772 Group who will run the Zabbix agent.
19774 Defaults to @samp{"zabbix"}.
19778 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
19779 Unique, case sensitive hostname which is required for active checks and
19780 must match hostname as configured on the server.
19782 Defaults to @samp{"Zabbix server"}.
19786 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
19787 Specifies where log messages are written to:
19791 @code{system} - syslog.
19794 @code{file} - file specified with @code{log-file} parameter.
19797 @code{console} - standard output.
19801 Defaults to @samp{""}.
19805 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
19806 Log file name for @code{log-type} @code{file} parameter.
19808 Defaults to @samp{"/var/log/zabbix/agent.log"}.
19812 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
19815 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
19819 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
19820 List of IP addresses, optionally in CIDR notation, or hostnames of
19821 Zabbix servers and Zabbix proxies. Incoming connections will be
19822 accepted only from the hosts listed here.
19824 Defaults to @samp{("127.0.0.1")}.
19828 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
19829 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
19830 proxies for active checks. If port is not specified, default port is
19831 used. If this parameter is not specified, active checks are disabled.
19833 Defaults to @samp{("127.0.0.1")}.
19837 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
19838 Extra options will be appended to Zabbix server configuration file.
19840 Defaults to @samp{""}.
19844 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
19845 You may include individual files or all files in a directory in the
19846 configuration file.
19848 Defaults to @samp{()}.
19852 @c %end of fragment
19854 @subsubheading Zabbix front-end
19855 @cindex zabbix zabbix-front-end
19857 This service provides a WEB interface to Zabbix server.
19859 @c %start of fragment
19861 Available @code{zabbix-front-end-configuration} fields are:
19863 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
19864 NGINX configuration.
19868 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
19869 Database host name.
19871 Defaults to @samp{"localhost"}.
19875 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
19878 Defaults to @samp{5432}.
19882 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
19885 Defaults to @samp{"zabbix"}.
19889 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
19892 Defaults to @samp{"zabbix"}.
19896 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
19897 Database password. Please, use @code{db-secret-file} instead.
19899 Defaults to @samp{""}.
19903 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
19904 Secret file which will be appended to @file{zabbix.conf.php} file. This
19905 file contains credentials for use by Zabbix front-end. You are expected
19906 to create it manually.
19908 Defaults to @samp{""}.
19912 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
19913 Zabbix server hostname.
19915 Defaults to @samp{"localhost"}.
19919 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
19920 Zabbix server port.
19922 Defaults to @samp{10051}.
19927 @c %end of fragment
19929 @node Kerberos Services
19930 @subsection Kerberos Services
19933 The @code{(gnu services kerberos)} module provides services relating to
19934 the authentication protocol @dfn{Kerberos}.
19936 @subsubheading Krb5 Service
19938 Programs using a Kerberos client library normally
19939 expect a configuration file in @file{/etc/krb5.conf}.
19940 This service generates such a file from a definition provided in the
19941 operating system declaration.
19942 It does not cause any daemon to be started.
19944 No ``keytab'' files are provided by this service---you must explicitly create them.
19945 This service is known to work with the MIT client library, @code{mit-krb5}.
19946 Other implementations have not been tested.
19948 @defvr {Scheme Variable} krb5-service-type
19949 A service type for Kerberos 5 clients.
19953 Here is an example of its use:
19955 (service krb5-service-type
19956 (krb5-configuration
19957 (default-realm "EXAMPLE.COM")
19958 (allow-weak-crypto? #t)
19961 (name "EXAMPLE.COM")
19962 (admin-server "groucho.example.com")
19963 (kdc "karl.example.com"))
19966 (admin-server "kerb-admin.argrx.edu")
19967 (kdc "keys.argrx.edu"))))))
19971 This example provides a Kerberos@tie{}5 client configuration which:
19973 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
19974 of which have distinct administration servers and key distribution centers;
19975 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
19976 specified by clients;
19977 @item Accepts services which only support encryption types known to be weak.
19980 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
19981 Only the most commonly used ones are described here.
19982 For a full list, and more detailed explanation of each, see the MIT
19983 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
19987 @deftp {Data Type} krb5-realm
19988 @cindex realm, kerberos
19991 This field is a string identifying the name of the realm.
19992 A common convention is to use the fully qualified DNS name of your organization,
19993 converted to upper case.
19995 @item @code{admin-server}
19996 This field is a string identifying the host where the administration server is
20000 This field is a string identifying the key distribution center
20005 @deftp {Data Type} krb5-configuration
20008 @item @code{allow-weak-crypto?} (default: @code{#f})
20009 If this flag is @code{#t} then services which only offer encryption algorithms
20010 known to be weak will be accepted.
20012 @item @code{default-realm} (default: @code{#f})
20013 This field should be a string identifying the default Kerberos
20014 realm for the client.
20015 You should set this field to the name of your Kerberos realm.
20016 If this value is @code{#f}
20017 then a realm must be specified with every Kerberos principal when invoking programs
20018 such as @command{kinit}.
20020 @item @code{realms}
20021 This should be a non-empty list of @code{krb5-realm} objects, which clients may
20023 Normally, one of them will have a @code{name} field matching the @code{default-realm}
20029 @subsubheading PAM krb5 Service
20032 The @code{pam-krb5} service allows for login authentication and password
20033 management via Kerberos.
20034 You will need this service if you want PAM enabled applications to authenticate
20035 users using Kerberos.
20037 @defvr {Scheme Variable} pam-krb5-service-type
20038 A service type for the Kerberos 5 PAM module.
20041 @deftp {Data Type} pam-krb5-configuration
20042 Data type representing the configuration of the Kerberos 5 PAM module.
20043 This type has the following parameters:
20045 @item @code{pam-krb5} (default: @code{pam-krb5})
20046 The pam-krb5 package to use.
20048 @item @code{minimum-uid} (default: @code{1000})
20049 The smallest user ID for which Kerberos authentications should be attempted.
20050 Local accounts with lower values will silently fail to authenticate.
20055 @node LDAP Services
20056 @subsection LDAP Services
20058 @cindex nslcd, LDAP service
20060 The @code{(gnu services authentication)} module provides the
20061 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
20062 server. In addition to configuring the service itself, you may want to add
20063 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
20064 Switch} for detailed information.
20066 Here is a simple operating system declaration with a default configuration of
20067 the @code{nslcd-service-type} and a Name Service Switch configuration that
20068 consults the @code{ldap} name service last:
20071 (use-service-modules authentication)
20072 (use-modules (gnu system nss))
20078 (service nslcd-service-type)
20079 (service dhcp-client-service-type)
20081 (name-service-switch
20082 (let ((services (list (name-service (name "db"))
20083 (name-service (name "files"))
20084 (name-service (name "ldap")))))
20085 (name-service-switch
20086 (inherit %mdns-host-lookup-nss)
20087 (password services)
20090 (netgroup services)
20091 (gshadow services)))))
20094 @c %start of generated documentation for nslcd-configuration
20096 Available @code{nslcd-configuration} fields are:
20098 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
20099 The @code{nss-pam-ldapd} package to use.
20103 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
20104 The number of threads to start that can handle requests and perform LDAP
20105 queries. Each thread opens a separate connection to the LDAP server.
20106 The default is to start 5 threads.
20108 Defaults to @samp{disabled}.
20112 @deftypevr {@code{nslcd-configuration} parameter} string uid
20113 This specifies the user id with which the daemon should be run.
20115 Defaults to @samp{"nslcd"}.
20119 @deftypevr {@code{nslcd-configuration} parameter} string gid
20120 This specifies the group id with which the daemon should be run.
20122 Defaults to @samp{"nslcd"}.
20126 @deftypevr {@code{nslcd-configuration} parameter} log-option log
20127 This option controls the way logging is done via a list containing
20128 SCHEME and LEVEL. The SCHEME argument may either be the symbols
20129 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
20130 argument is optional and specifies the log level. The log level may be
20131 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
20132 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
20133 specified log level or higher are logged.
20135 Defaults to @samp{("/var/log/nslcd" info)}.
20139 @deftypevr {@code{nslcd-configuration} parameter} list uri
20140 The list of LDAP server URIs. Normally, only the first server will be
20141 used with the following servers as fall-back.
20143 Defaults to @samp{("ldap://localhost:389/")}.
20147 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
20148 The version of the LDAP protocol to use. The default is to use the
20149 maximum version supported by the LDAP library.
20151 Defaults to @samp{disabled}.
20155 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
20156 Specifies the distinguished name with which to bind to the directory
20157 server for lookups. The default is to bind anonymously.
20159 Defaults to @samp{disabled}.
20163 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
20164 Specifies the credentials with which to bind. This option is only
20165 applicable when used with binddn.
20167 Defaults to @samp{disabled}.
20171 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
20172 Specifies the distinguished name to use when the root user tries to
20173 modify a user's password using the PAM module.
20175 Defaults to @samp{disabled}.
20179 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
20180 Specifies the credentials with which to bind if the root user tries to
20181 change a user's password. This option is only applicable when used with
20184 Defaults to @samp{disabled}.
20188 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
20189 Specifies the SASL mechanism to be used when performing SASL
20192 Defaults to @samp{disabled}.
20196 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
20197 Specifies the SASL realm to be used when performing SASL authentication.
20199 Defaults to @samp{disabled}.
20203 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
20204 Specifies the authentication identity to be used when performing SASL
20207 Defaults to @samp{disabled}.
20211 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
20212 Specifies the authorization identity to be used when performing SASL
20215 Defaults to @samp{disabled}.
20219 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
20220 Determines whether the LDAP server host name should be canonicalised. If
20221 this is enabled the LDAP library will do a reverse host name lookup. By
20222 default, it is left up to the LDAP library whether this check is
20225 Defaults to @samp{disabled}.
20229 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
20230 Set the name for the GSS-API Kerberos credentials cache.
20232 Defaults to @samp{disabled}.
20236 @deftypevr {@code{nslcd-configuration} parameter} string base
20237 The directory search base.
20239 Defaults to @samp{"dc=example,dc=com"}.
20243 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
20244 Specifies the search scope (subtree, onelevel, base or children). The
20245 default scope is subtree; base scope is almost never useful for name
20246 service lookups; children scope is not supported on all servers.
20248 Defaults to @samp{(subtree)}.
20252 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
20253 Specifies the policy for dereferencing aliases. The default policy is
20254 to never dereference aliases.
20256 Defaults to @samp{disabled}.
20260 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
20261 Specifies whether automatic referral chasing should be enabled. The
20262 default behaviour is to chase referrals.
20264 Defaults to @samp{disabled}.
20268 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
20269 This option allows for custom attributes to be looked up instead of the
20270 default RFC 2307 attributes. It is a list of maps, each consisting of
20271 the name of a map, the RFC 2307 attribute to match and the query
20272 expression for the attribute as it is available in the directory.
20274 Defaults to @samp{()}.
20278 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
20279 A list of filters consisting of the name of a map to which the filter
20280 applies and an LDAP search filter expression.
20282 Defaults to @samp{()}.
20286 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
20287 Specifies the time limit in seconds to use when connecting to the
20288 directory server. The default value is 10 seconds.
20290 Defaults to @samp{disabled}.
20294 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
20295 Specifies the time limit (in seconds) to wait for a response from the
20296 LDAP server. A value of zero, which is the default, is to wait
20297 indefinitely for searches to be completed.
20299 Defaults to @samp{disabled}.
20303 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
20304 Specifies the period if inactivity (in seconds) after which the con‐
20305 nection to the LDAP server will be closed. The default is not to time
20308 Defaults to @samp{disabled}.
20312 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
20313 Specifies the number of seconds to sleep when connecting to all LDAP
20314 servers fails. By default one second is waited between the first
20315 failure and the first retry.
20317 Defaults to @samp{disabled}.
20321 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
20322 Specifies the time after which the LDAP server is considered to be
20323 permanently unavailable. Once this time is reached retries will be done
20324 only once per this time period. The default value is 10 seconds.
20326 Defaults to @samp{disabled}.
20330 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
20331 Specifies whether to use SSL/TLS or not (the default is not to). If
20332 'start-tls is specified then StartTLS is used rather than raw LDAP over
20335 Defaults to @samp{disabled}.
20339 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
20340 Specifies what checks to perform on a server-supplied certificate. The
20341 meaning of the values is described in the ldap.conf(5) manual page.
20343 Defaults to @samp{disabled}.
20347 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
20348 Specifies the directory containing X.509 certificates for peer authen‐
20349 tication. This parameter is ignored when using GnuTLS.
20351 Defaults to @samp{disabled}.
20355 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
20356 Specifies the path to the X.509 certificate for peer authentication.
20358 Defaults to @samp{disabled}.
20362 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
20363 Specifies the path to an entropy source. This parameter is ignored when
20366 Defaults to @samp{disabled}.
20370 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
20371 Specifies the ciphers to use for TLS as a string.
20373 Defaults to @samp{disabled}.
20377 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
20378 Specifies the path to the file containing the local certificate for
20379 client TLS authentication.
20381 Defaults to @samp{disabled}.
20385 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
20386 Specifies the path to the file containing the private key for client TLS
20389 Defaults to @samp{disabled}.
20393 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
20394 Set this to a number greater than 0 to request paged results from the
20395 LDAP server in accordance with RFC2696. The default (0) is to not
20396 request paged results.
20398 Defaults to @samp{disabled}.
20402 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
20403 This option prevents group membership lookups through LDAP for the
20404 specified users. Alternatively, the value 'all-local may be used. With
20405 that value nslcd builds a full list of non-LDAP users on startup.
20407 Defaults to @samp{disabled}.
20411 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
20412 This option ensures that LDAP users with a numeric user id lower than
20413 the specified value are ignored.
20415 Defaults to @samp{disabled}.
20419 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
20420 This option specifies an offset that is added to all LDAP numeric user
20421 ids. This can be used to avoid user id collisions with local users.
20423 Defaults to @samp{disabled}.
20427 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
20428 This option specifies an offset that is added to all LDAP numeric group
20429 ids. This can be used to avoid user id collisions with local groups.
20431 Defaults to @samp{disabled}.
20435 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
20436 If this option is set, the member attribute of a group may point to
20437 another group. Members of nested groups are also returned in the higher
20438 level group and parent groups are returned when finding groups for a
20439 specific user. The default is not to perform extra searches for nested
20442 Defaults to @samp{disabled}.
20446 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
20447 If this option is set, the group member list is not retrieved when
20448 looking up groups. Lookups for finding which groups a user belongs to
20449 will remain functional so the user will likely still get the correct
20450 groups assigned on login.
20452 Defaults to @samp{disabled}.
20456 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
20457 If this option is set, functions which cause all user/group entries to
20458 be loaded from the directory will not succeed in doing so. This can
20459 dramatically reduce LDAP server load in situations where there are a
20460 great number of users and/or groups. This option is not recommended for
20461 most configurations.
20463 Defaults to @samp{disabled}.
20467 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
20468 This option can be used to specify how user and group names are verified
20469 within the system. This pattern is used to check all user and group
20470 names that are requested and returned from LDAP.
20472 Defaults to @samp{disabled}.
20476 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
20477 This specifies whether or not to perform searches using case-insensitive
20478 matching. Enabling this could open up the system to authorization
20479 bypass vulnerabilities and introduce nscd cache poisoning
20480 vulnerabilities which allow denial of service.
20482 Defaults to @samp{disabled}.
20486 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
20487 This option specifies whether password policy controls are requested and
20488 handled from the LDAP server when performing user authentication.
20490 Defaults to @samp{disabled}.
20494 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
20495 By default nslcd performs an LDAP search with the user's credentials
20496 after BIND (authentication) to ensure that the BIND operation was
20497 successful. The default search is a simple check to see if the user's
20498 DN exists. A search filter can be specified that will be used instead.
20499 It should return at least one entry.
20501 Defaults to @samp{disabled}.
20505 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
20506 This option allows flexible fine tuning of the authorisation check that
20507 should be performed. The search filter specified is executed and if any
20508 entries match, access is granted, otherwise access is denied.
20510 Defaults to @samp{disabled}.
20514 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
20515 If this option is set password modification using pam_ldap will be
20516 denied and the specified message will be presented to the user instead.
20517 The message can be used to direct the user to an alternative means of
20518 changing their password.
20520 Defaults to @samp{disabled}.
20524 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
20525 List of pam service names for which LDAP authentication should suffice.
20527 Defaults to @samp{()}.
20531 @c %end of generated documentation for nslcd-configuration
20535 @subsection Web Services
20540 The @code{(gnu services web)} module provides the Apache HTTP Server,
20541 the nginx web server, and also a fastcgi wrapper daemon.
20543 @subsubheading Apache HTTP Server
20545 @deffn {Scheme Variable} httpd-service-type
20546 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
20547 (@dfn{httpd}). The value for this service type is a
20548 @code{httpd-configuration} record.
20550 A simple example configuration is given below.
20553 (service httpd-service-type
20554 (httpd-configuration
20557 (server-name "www.example.com")
20558 (document-root "/srv/http/www.example.com")))))
20561 Other services can also extend the @code{httpd-service-type} to add to
20565 (simple-service 'www.example.com-server httpd-service-type
20569 (list (string-join '("ServerName www.example.com"
20570 "DocumentRoot /srv/http/www.example.com")
20575 The details for the @code{httpd-configuration}, @code{httpd-module},
20576 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
20579 @deffn {Data Type} httpd-configuration
20580 This data type represents the configuration for the httpd service.
20583 @item @code{package} (default: @code{httpd})
20584 The httpd package to use.
20586 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20587 The pid file used by the shepherd-service.
20589 @item @code{config} (default: @code{(httpd-config-file)})
20590 The configuration file to use with the httpd service. The default value
20591 is a @code{httpd-config-file} record, but this can also be a different
20592 G-expression that generates a file, for example a @code{plain-file}. A
20593 file outside of the store can also be specified through a string.
20598 @deffn {Data Type} httpd-module
20599 This data type represents a module for the httpd service.
20603 The name of the module.
20606 The file for the module. This can be relative to the httpd package being
20607 used, the absolute location of a file, or a G-expression for a file
20608 within the store, for example @code{(file-append mod-wsgi
20609 "/modules/mod_wsgi.so")}.
20614 @defvr {Scheme Variable} %default-httpd-modules
20615 A default list of @code{httpd-module} objects.
20618 @deffn {Data Type} httpd-config-file
20619 This data type represents a configuration file for the httpd service.
20622 @item @code{modules} (default: @code{%default-httpd-modules})
20623 The modules to load. Additional modules can be added here, or loaded by
20624 additional configuration.
20626 For example, in order to handle requests for PHP files, you can use Apache’s
20627 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
20630 (service httpd-service-type
20631 (httpd-configuration
20636 (name "proxy_module")
20637 (file "modules/mod_proxy.so"))
20639 (name "proxy_fcgi_module")
20640 (file "modules/mod_proxy_fcgi.so"))
20641 %default-httpd-modules))
20642 (extra-config (list "\
20643 <FilesMatch \\.php$>
20644 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
20645 </FilesMatch>"))))))
20646 (service php-fpm-service-type
20647 (php-fpm-configuration
20648 (socket "/var/run/php-fpm.sock")
20649 (socket-group "httpd")))
20652 @item @code{server-root} (default: @code{httpd})
20653 The @code{ServerRoot} in the configuration file, defaults to the httpd
20654 package. Directives including @code{Include} and @code{LoadModule} are
20655 taken as relative to the server root.
20657 @item @code{server-name} (default: @code{#f})
20658 The @code{ServerName} in the configuration file, used to specify the
20659 request scheme, hostname and port that the server uses to identify
20662 This doesn't need to be set in the server config, and can be specified
20663 in virtual hosts. The default is @code{#f} to not specify a
20666 @item @code{document-root} (default: @code{"/srv/http"})
20667 The @code{DocumentRoot} from which files will be served.
20669 @item @code{listen} (default: @code{'("80")})
20670 The list of values for the @code{Listen} directives in the config
20671 file. The value should be a list of strings, when each string can
20672 specify the port number to listen on, and optionally the IP address and
20675 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20676 The @code{PidFile} to use. This should match the @code{pid-file} set in
20677 the @code{httpd-configuration} so that the Shepherd service is
20678 configured correctly.
20680 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
20681 The @code{ErrorLog} to which the server will log errors.
20683 @item @code{user} (default: @code{"httpd"})
20684 The @code{User} which the server will answer requests as.
20686 @item @code{group} (default: @code{"httpd"})
20687 The @code{Group} which the server will answer requests as.
20689 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
20690 A flat list of strings and G-expressions which will be added to the end
20691 of the configuration file.
20693 Any values which the service is extended with will be appended to this
20699 @deffn {Data Type} httpd-virtualhost
20700 This data type represents a virtualhost configuration block for the httpd service.
20702 These should be added to the extra-config for the httpd-service.
20705 (simple-service 'www.example.com-server httpd-service-type
20709 (list (string-join '("ServerName www.example.com"
20710 "DocumentRoot /srv/http/www.example.com")
20715 @item @code{addresses-and-ports}
20716 The addresses and ports for the @code{VirtualHost} directive.
20718 @item @code{contents}
20719 The contents of the @code{VirtualHost} directive, this should be a list
20720 of strings and G-expressions.
20725 @subsubheading NGINX
20727 @deffn {Scheme Variable} nginx-service-type
20728 Service type for the @uref{https://nginx.org/,NGinx} web server. The
20729 value for this service type is a @code{<nginx-configuration>} record.
20731 A simple example configuration is given below.
20734 (service nginx-service-type
20735 (nginx-configuration
20737 (list (nginx-server-configuration
20738 (server-name '("www.example.com"))
20739 (root "/srv/http/www.example.com"))))))
20742 In addition to adding server blocks to the service configuration
20743 directly, this service can be extended by other services to add server
20744 blocks, as in this example:
20747 (simple-service 'my-extra-server nginx-service-type
20748 (list (nginx-server-configuration
20749 (root "/srv/http/extra-website")
20750 (try-files (list "$uri" "$uri/index.html")))))
20754 At startup, @command{nginx} has not yet read its configuration file, so
20755 it uses a default file to log error messages. If it fails to load its
20756 configuration file, that is where error messages are logged. After the
20757 configuration file is loaded, the default error log file changes as per
20758 configuration. In our case, startup error messages can be found in
20759 @file{/var/run/nginx/logs/error.log}, and after configuration in
20760 @file{/var/log/nginx/error.log}. The second location can be changed
20761 with the @var{log-directory} configuration option.
20763 @deffn {Data Type} nginx-configuration
20764 This data type represents the configuration for NGinx. Some
20765 configuration can be done through this and the other provided record
20766 types, or alternatively, a config file can be provided.
20769 @item @code{nginx} (default: @code{nginx})
20770 The nginx package to use.
20772 @item @code{log-directory} (default: @code{"/var/log/nginx"})
20773 The directory to which NGinx will write log files.
20775 @item @code{run-directory} (default: @code{"/var/run/nginx"})
20776 The directory in which NGinx will create a pid file, and write temporary
20779 @item @code{server-blocks} (default: @code{'()})
20780 A list of @dfn{server blocks} to create in the generated configuration
20781 file, the elements should be of type
20782 @code{<nginx-server-configuration>}.
20784 The following example would setup NGinx to serve @code{www.example.com}
20785 from the @code{/srv/http/www.example.com} directory, without using
20788 (service nginx-service-type
20789 (nginx-configuration
20791 (list (nginx-server-configuration
20792 (server-name '("www.example.com"))
20793 (root "/srv/http/www.example.com"))))))
20796 @item @code{upstream-blocks} (default: @code{'()})
20797 A list of @dfn{upstream blocks} to create in the generated configuration
20798 file, the elements should be of type
20799 @code{<nginx-upstream-configuration>}.
20801 Configuring upstreams through the @code{upstream-blocks} can be useful
20802 when combined with @code{locations} in the
20803 @code{<nginx-server-configuration>} records. The following example
20804 creates a server configuration with one location configuration, that
20805 will proxy requests to a upstream configuration, which will handle
20806 requests with two servers.
20811 (nginx-configuration
20813 (list (nginx-server-configuration
20814 (server-name '("www.example.com"))
20815 (root "/srv/http/www.example.com")
20818 (nginx-location-configuration
20820 (body '("proxy_pass http://server-proxy;"))))))))
20822 (list (nginx-upstream-configuration
20823 (name "server-proxy")
20824 (servers (list "server1.example.com"
20825 "server2.example.com")))))))
20828 @item @code{file} (default: @code{#f})
20829 If a configuration @var{file} is provided, this will be used, rather than
20830 generating a configuration file from the provided @code{log-directory},
20831 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
20832 proper operation, these arguments should match what is in @var{file} to ensure
20833 that the directories are created when the service is activated.
20835 This can be useful if you have an existing configuration file, or it's
20836 not possible to do what is required through the other parts of the
20837 nginx-configuration record.
20839 @item @code{server-names-hash-bucket-size} (default: @code{#f})
20840 Bucket size for the server names hash tables, defaults to @code{#f} to
20841 use the size of the processors cache line.
20843 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
20844 Maximum bucket size for the server names hash tables.
20846 @item @code{modules} (default: @code{'()})
20847 List of nginx dynamic modules to load. This should be a list of file
20848 names of loadable modules, as in this example:
20853 (file-append nginx-accept-language-module "\
20854 /etc/nginx/modules/ngx_http_accept_language_module.so")))
20857 @item @code{global-directives} (default: @code{'((events . ()))})
20858 Association list of global directives for the top level of the nginx
20859 configuration. Values may themselves be association lists.
20863 `((worker_processes . 16)
20865 (events . ((worker_connections . 1024)))))
20868 @item @code{extra-content} (default: @code{""})
20869 Extra content for the @code{http} block. Should be string or a string
20870 valued G-expression.
20875 @deftp {Data Type} nginx-server-configuration
20876 Data type representing the configuration of an nginx server block.
20877 This type has the following parameters:
20880 @item @code{listen} (default: @code{'("80" "443 ssl")})
20881 Each @code{listen} directive sets the address and port for IP, or the
20882 path for a UNIX-domain socket on which the server will accept requests.
20883 Both address and port, or only address or only port can be specified.
20884 An address may also be a hostname, for example:
20887 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
20890 @item @code{server-name} (default: @code{(list 'default)})
20891 A list of server names this server represents. @code{'default} represents the
20892 default server for connections matching no other server.
20894 @item @code{root} (default: @code{"/srv/http"})
20895 Root of the website nginx will serve.
20897 @item @code{locations} (default: @code{'()})
20898 A list of @dfn{nginx-location-configuration} or
20899 @dfn{nginx-named-location-configuration} records to use within this
20902 @item @code{index} (default: @code{(list "index.html")})
20903 Index files to look for when clients ask for a directory. If it cannot be found,
20904 Nginx will send the list of files in the directory.
20906 @item @code{try-files} (default: @code{'()})
20907 A list of files whose existence is checked in the specified order.
20908 @code{nginx} will use the first file it finds to process the request.
20910 @item @code{ssl-certificate} (default: @code{#f})
20911 Where to find the certificate for secure connections. Set it to @code{#f} if
20912 you don't have a certificate or you don't want to use HTTPS.
20914 @item @code{ssl-certificate-key} (default: @code{#f})
20915 Where to find the private key for secure connections. Set it to @code{#f} if
20916 you don't have a key or you don't want to use HTTPS.
20918 @item @code{server-tokens?} (default: @code{#f})
20919 Whether the server should add its configuration to response.
20921 @item @code{raw-content} (default: @code{'()})
20922 A list of raw lines added to the server block.
20927 @deftp {Data Type} nginx-upstream-configuration
20928 Data type representing the configuration of an nginx @code{upstream}
20929 block. This type has the following parameters:
20933 Name for this group of servers.
20935 @item @code{servers}
20936 Specify the addresses of the servers in the group. The address can be
20937 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
20938 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
20939 prefix @samp{unix:}. For addresses using an IP address or domain name,
20940 the default port is 80, and a different port can be specified
20946 @deftp {Data Type} nginx-location-configuration
20947 Data type representing the configuration of an nginx @code{location}
20948 block. This type has the following parameters:
20952 URI which this location block matches.
20954 @anchor{nginx-location-configuration body}
20956 Body of the location block, specified as a list of strings. This can contain
20958 configuration directives. For example, to pass requests to a upstream
20959 server group defined using an @code{nginx-upstream-configuration} block,
20960 the following directive would be specified in the body @samp{(list "proxy_pass
20961 http://upstream-name;")}.
20966 @deftp {Data Type} nginx-named-location-configuration
20967 Data type representing the configuration of an nginx named location
20968 block. Named location blocks are used for request redirection, and not
20969 used for regular request processing. This type has the following
20974 Name to identify this location block.
20977 @xref{nginx-location-configuration body}, as the body for named location
20978 blocks can be used in a similar way to the
20979 @code{nginx-location-configuration body}. One restriction is that the
20980 body of a named location block cannot contain location blocks.
20985 @subsubheading Varnish Cache
20987 Varnish is a fast cache server that sits in between web applications
20988 and end users. It proxies requests from clients and caches the
20989 accessed URLs such that multiple requests for the same resource only
20990 creates one request to the back-end.
20992 @defvr {Scheme Variable} varnish-service-type
20993 Service type for the Varnish daemon.
20996 @deftp {Data Type} varnish-configuration
20997 Data type representing the @code{varnish} service configuration.
20998 This type has the following parameters:
21001 @item @code{package} (default: @code{varnish})
21002 The Varnish package to use.
21004 @item @code{name} (default: @code{"default"})
21005 A name for this Varnish instance. Varnish will create a directory in
21006 @file{/var/varnish/} with this name and keep temporary files there. If
21007 the name starts with a forward slash, it is interpreted as an absolute
21010 Pass the @code{-n} argument to other Varnish programs to connect to the
21011 named instance, e.g.@: @command{varnishncsa -n default}.
21013 @item @code{backend} (default: @code{"localhost:8080"})
21014 The backend to use. This option has no effect if @code{vcl} is set.
21016 @item @code{vcl} (default: #f)
21017 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
21018 is @code{#f}, Varnish will proxy @code{backend} using the default
21019 configuration. Otherwise this must be a file-like object with valid
21022 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
21023 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
21024 can do something along these lines:
21027 (define %gnu-mirror
21028 (plain-file "gnu.vcl"
21030 backend gnu @{ .host = \"www.gnu.org\"; @}"))
21034 (services (cons (service varnish-service-type
21035 (varnish-configuration
21037 (vcl %gnu-mirror)))
21041 The configuration of an already running Varnish instance can be inspected
21042 and changed using the @command{varnishadm} program.
21044 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
21045 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
21046 comprehensive documentation on Varnish and its configuration language.
21048 @item @code{listen} (default: @code{'("localhost:80")})
21049 List of addresses Varnish will listen on.
21051 @item @code{storage} (default: @code{'("malloc,128m")})
21052 List of storage backends that will be available in VCL.
21054 @item @code{parameters} (default: @code{'()})
21055 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
21057 @item @code{extra-options} (default: @code{'()})
21058 Additional arguments to pass to the @command{varnishd} process.
21063 @subsubheading Patchwork
21065 Patchwork is a patch tracking system. It can collect patches sent to a
21066 mailing list, and display them in a web interface.
21068 @defvr {Scheme Variable} patchwork-service-type
21069 Service type for Patchwork.
21072 The following example is an example of a minimal service for Patchwork, for
21073 the @code{patchwork.example.com} domain.
21076 (service patchwork-service-type
21077 (patchwork-configuration
21078 (domain "patchwork.example.com")
21080 (patchwork-settings-module
21081 (allowed-hosts (list domain))
21082 (default-from-email "patchwork@@patchwork.example.com")))
21083 (getmail-retriever-config
21084 (getmail-retriever-configuration
21085 (type "SimpleIMAPSSLRetriever")
21086 (server "imap.example.com")
21088 (username "patchwork")
21090 (list (file-append coreutils "/bin/cat")
21091 "/etc/getmail-patchwork-imap-password"))
21093 '((mailboxes . ("Patches"))))))))
21097 There are three records for configuring the Patchwork service. The
21098 @code{<patchwork-configuration>} relates to the configuration for Patchwork
21099 within the HTTPD service.
21101 The @code{settings-module} field within the @code{<patchwork-configuration>}
21102 record can be populated with the @code{<patchwork-settings-module>} record,
21103 which describes a settings module that is generated within the Guix store.
21105 For the @code{database-configuration} field within the
21106 @code{<patchwork-settings-module>}, the
21107 @code{<patchwork-database-configuration>} must be used.
21109 @deftp {Data Type} patchwork-configuration
21110 Data type representing the Patchwork service configuration. This type has the
21111 following parameters:
21114 @item @code{patchwork} (default: @code{patchwork})
21115 The Patchwork package to use.
21117 @item @code{domain}
21118 The domain to use for Patchwork, this is used in the HTTPD service virtual
21121 @item @code{settings-module}
21122 The settings module to use for Patchwork. As a Django application, Patchwork
21123 is configured with a Python module containing the settings. This can either be
21124 an instance of the @code{<patchwork-settings-module>} record, any other record
21125 that represents the settings in the store, or a directory outside of the
21128 @item @code{static-path} (default: @code{"/static/"})
21129 The path under which the HTTPD service should serve the static files.
21131 @item @code{getmail-retriever-config}
21132 The getmail-retriever-configuration record value to use with
21133 Patchwork. Getmail will be configured with this value, the messages will be
21134 delivered to Patchwork.
21139 @deftp {Data Type} patchwork-settings-module
21140 Data type representing a settings module for Patchwork. Some of these
21141 settings relate directly to Patchwork, but others relate to Django, the web
21142 framework used by Patchwork, or the Django Rest Framework library. This type
21143 has the following parameters:
21146 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
21147 The database connection settings used for Patchwork. See the
21148 @code{<patchwork-database-configuration>} record type for more information.
21150 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
21151 Patchwork, as a Django web application uses a secret key for cryptographically
21152 signing values. This file should contain a unique unpredictable value.
21154 If this file does not exist, it will be created and populated with a random
21155 value by the patchwork-setup shepherd service.
21157 This setting relates to Django.
21159 @item @code{allowed-hosts}
21160 A list of valid hosts for this Patchwork service. This should at least include
21161 the domain specified in the @code{<patchwork-configuration>} record.
21163 This is a Django setting.
21165 @item @code{default-from-email}
21166 The email address from which Patchwork should send email by default.
21168 This is a Patchwork setting.
21170 @item @code{static-url} (default: @code{#f})
21171 The URL to use when serving static assets. It can be part of a URL, or a full
21172 URL, but must end in a @code{/}.
21174 If the default value is used, the @code{static-path} value from the
21175 @code{<patchwork-configuration>} record will be used.
21177 This is a Django setting.
21179 @item @code{admins} (default: @code{'()})
21180 Email addresses to send the details of errors that occur. Each value should
21181 be a list containing two elements, the name and then the email address.
21183 This is a Django setting.
21185 @item @code{debug?} (default: @code{#f})
21186 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
21187 messages will be shown.
21189 This is a Django setting.
21191 @item @code{enable-rest-api?} (default: @code{#t})
21192 Whether to enable the Patchwork REST API.
21194 This is a Patchwork setting.
21196 @item @code{enable-xmlrpc?} (default: @code{#t})
21197 Whether to enable the XML RPC API.
21199 This is a Patchwork setting.
21201 @item @code{force-https-links?} (default: @code{#t})
21202 Whether to use HTTPS links on Patchwork pages.
21204 This is a Patchwork setting.
21206 @item @code{extra-settings} (default: @code{""})
21207 Extra code to place at the end of the Patchwork settings module.
21212 @deftp {Data Type} patchwork-database-configuration
21213 Data type representing the database configuration for Patchwork.
21216 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
21217 The database engine to use.
21219 @item @code{name} (default: @code{"patchwork"})
21220 The name of the database to use.
21222 @item @code{user} (default: @code{"httpd"})
21223 The user to connect to the database as.
21225 @item @code{password} (default: @code{""})
21226 The password to use when connecting to the database.
21228 @item @code{host} (default: @code{""})
21229 The host to make the database connection to.
21231 @item @code{port} (default: @code{""})
21232 The port on which to connect to the database.
21237 @subsubheading Mumi
21239 @cindex Mumi, Debbugs Web interface
21240 @cindex Debbugs, Mumi Web interface
21241 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
21242 Web interface to the Debbugs bug tracker, by default for
21243 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
21244 but it also fetches and indexes mail retrieved from Debbugs.
21246 @defvr {Scheme Variable} mumi-service-type
21247 This is the service type for Mumi.
21250 @deftp {Data Type} mumi-configuration
21251 Data type representing the Mumi service configuration. This type has the
21255 @item @code{mumi} (default: @code{mumi})
21256 The Mumi package to use.
21258 @item @code{mailer?} (default: @code{#true})
21259 Whether to enable or disable the mailer component.
21261 @item @code{mumi-configuration-sender}
21262 The email address used as the sender for comments.
21264 @item @code{mumi-configuration-smtp}
21265 A URI to configure the SMTP settings for Mailutils. This could be
21266 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
21267 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
21268 mailutils, GNU@tie{}Mailutils}.
21274 @subsubheading FastCGI
21277 FastCGI is an interface between the front-end and the back-end of a web
21278 service. It is a somewhat legacy facility; new web services should
21279 generally just talk HTTP between the front-end and the back-end.
21280 However there are a number of back-end services such as PHP or the
21281 optimized HTTP Git repository access that use FastCGI, so we have
21282 support for it in Guix.
21284 To use FastCGI, you configure the front-end web server (e.g., nginx) to
21285 dispatch some subset of its requests to the fastcgi backend, which
21286 listens on a local TCP or UNIX socket. There is an intermediary
21287 @code{fcgiwrap} program that sits between the actual backend process and
21288 the web server. The front-end indicates which backend program to run,
21289 passing that information to the @code{fcgiwrap} process.
21291 @defvr {Scheme Variable} fcgiwrap-service-type
21292 A service type for the @code{fcgiwrap} FastCGI proxy.
21295 @deftp {Data Type} fcgiwrap-configuration
21296 Data type representing the configuration of the @code{fcgiwrap} service.
21297 This type has the following parameters:
21299 @item @code{package} (default: @code{fcgiwrap})
21300 The fcgiwrap package to use.
21302 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
21303 The socket on which the @code{fcgiwrap} process should listen, as a
21304 string. Valid @var{socket} values include
21305 @code{unix:@var{/path/to/unix/socket}},
21306 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
21307 @code{tcp6:[@var{ipv6_addr}]:port}.
21309 @item @code{user} (default: @code{fcgiwrap})
21310 @itemx @code{group} (default: @code{fcgiwrap})
21311 The user and group names, as strings, under which to run the
21312 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
21313 the user asks for the specific user or group names @code{fcgiwrap} that
21314 the corresponding user and/or group is present on the system.
21316 It is possible to configure a FastCGI-backed web service to pass HTTP
21317 authentication information from the front-end to the back-end, and to
21318 allow @code{fcgiwrap} to run the back-end process as a corresponding
21319 local user. To enable this capability on the back-end, run
21320 @code{fcgiwrap} as the @code{root} user and group. Note that this
21321 capability also has to be configured on the front-end as well.
21326 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
21327 with some additional features useful for sites of any size.
21329 These features include:
21331 @item Adaptive process spawning
21332 @item Basic statistics (similar to Apache's mod_status)
21333 @item Advanced process management with graceful stop/start
21334 @item Ability to start workers with different uid/gid/chroot/environment
21335 and different php.ini (replaces safe_mode)
21336 @item Stdout & stderr logging
21337 @item Emergency restart in case of accidental opcode cache destruction
21338 @item Accelerated upload support
21339 @item Support for a "slowlog"
21340 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
21341 a special function to finish request & flush all data while continuing to do
21342 something time-consuming (video converting, stats processing, etc.)
21344 ...@: and much more.
21346 @defvr {Scheme Variable} php-fpm-service-type
21347 A Service type for @code{php-fpm}.
21350 @deftp {Data Type} php-fpm-configuration
21351 Data Type for php-fpm service configuration.
21353 @item @code{php} (default: @code{php})
21354 The php package to use.
21355 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
21356 The address on which to accept FastCGI requests. Valid syntaxes are:
21358 @item @code{"ip.add.re.ss:port"}
21359 Listen on a TCP socket to a specific address on a specific port.
21360 @item @code{"port"}
21361 Listen on a TCP socket to all addresses on a specific port.
21362 @item @code{"/path/to/unix/socket"}
21363 Listen on a unix socket.
21366 @item @code{user} (default: @code{php-fpm})
21367 User who will own the php worker processes.
21368 @item @code{group} (default: @code{php-fpm})
21369 Group of the worker processes.
21370 @item @code{socket-user} (default: @code{php-fpm})
21371 User who can speak to the php-fpm socket.
21372 @item @code{socket-group} (default: @code{nginx})
21373 Group that can speak to the php-fpm socket.
21374 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
21375 The process id of the php-fpm process is written to this file
21376 once the service has started.
21377 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
21378 Log for the php-fpm master process.
21379 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
21380 Detailed settings for the php-fpm process manager.
21383 @item @code{<php-fpm-dynamic-process-manager-configuration>}
21384 @item @code{<php-fpm-static-process-manager-configuration>}
21385 @item @code{<php-fpm-on-demand-process-manager-configuration>}
21387 @item @code{display-errors} (default @code{#f})
21388 Determines whether php errors and warning should be sent to clients
21389 and displayed in their browsers.
21390 This is useful for local php development, but a security risk for public sites,
21391 as error messages can reveal passwords and personal data.
21392 @item @code{timezone} (default @code{#f})
21393 Specifies @code{php_admin_value[date.timezone]} parameter.
21394 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
21395 This file will log the @code{stderr} outputs of php worker processes.
21396 Can be set to @code{#f} to disable logging.
21397 @item @code{file} (default @code{#f})
21398 An optional override of the whole configuration.
21399 You can use the @code{mixed-text-file} function or an absolute filepath for it.
21403 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
21404 Data Type for the @code{dynamic} php-fpm process manager. With the
21405 @code{dynamic} process manager, spare worker processes are kept around
21406 based on it's configured limits.
21408 @item @code{max-children} (default: @code{5})
21409 Maximum of worker processes.
21410 @item @code{start-servers} (default: @code{2})
21411 How many worker processes should be started on start-up.
21412 @item @code{min-spare-servers} (default: @code{1})
21413 How many spare worker processes should be kept around at minimum.
21414 @item @code{max-spare-servers} (default: @code{3})
21415 How many spare worker processes should be kept around at maximum.
21419 @deftp {Data type} php-fpm-static-process-manager-configuration
21420 Data Type for the @code{static} php-fpm process manager. With the
21421 @code{static} process manager, an unchanging number of worker processes
21424 @item @code{max-children} (default: @code{5})
21425 Maximum of worker processes.
21429 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
21430 Data Type for the @code{on-demand} php-fpm process manager. With the
21431 @code{on-demand} process manager, worker processes are only created as
21434 @item @code{max-children} (default: @code{5})
21435 Maximum of worker processes.
21436 @item @code{process-idle-timeout} (default: @code{10})
21437 The time in seconds after which a process with no requests is killed.
21442 @deffn {Scheme Procedure} nginx-php-location @
21443 [#:nginx-package nginx] @
21444 [socket (string-append "/var/run/php" @
21445 (version-major (package-version php)) @
21447 A helper function to quickly add php to an @code{nginx-server-configuration}.
21450 A simple services setup for nginx with php can look like this:
21452 (services (cons* (service dhcp-client-service-type)
21453 (service php-fpm-service-type)
21454 (service nginx-service-type
21455 (nginx-server-configuration
21456 (server-name '("example.com"))
21457 (root "/srv/http/")
21459 (list (nginx-php-location)))
21461 (ssl-certificate #f)
21462 (ssl-certificate-key #f)))
21466 @cindex cat-avatar-generator
21467 The cat avatar generator is a simple service to demonstrate the use of php-fpm
21468 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
21469 the hash of a user's email address.
21471 @deffn {Scheme Procedure} cat-avatar-generator-service @
21472 [#:cache-dir "/var/cache/cat-avatar-generator"] @
21473 [#:package cat-avatar-generator] @
21474 [#:configuration (nginx-server-configuration)]
21475 Returns an nginx-server-configuration that inherits @code{configuration}. It
21476 extends the nginx configuration to add a server block that serves @code{package},
21477 a version of cat-avatar-generator. During execution, cat-avatar-generator will
21478 be able to use @code{cache-dir} as its cache directory.
21481 A simple setup for cat-avatar-generator can look like this:
21483 (services (cons* (cat-avatar-generator-service
21485 (nginx-server-configuration
21486 (server-name '("example.com"))))
21491 @subsubheading Hpcguix-web
21493 @cindex hpcguix-web
21494 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
21495 program is a customizable web interface to browse Guix packages,
21496 initially designed for users of high-performance computing (HPC)
21499 @defvr {Scheme Variable} hpcguix-web-service-type
21500 The service type for @code{hpcguix-web}.
21503 @deftp {Data Type} hpcguix-web-configuration
21504 Data type for the hpcguix-web service configuration.
21508 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
21509 configuration. The main items available in this spec are:
21512 @item @code{title-prefix} (default: @code{"hpcguix | "})
21513 The page title prefix.
21515 @item @code{guix-command} (default: @code{"guix"})
21516 The @command{guix} command.
21518 @item @code{package-filter-proc} (default: @code{(const #t)})
21519 A procedure specifying how to filter packages that are displayed.
21521 @item @code{package-page-extension-proc} (default: @code{(const '())})
21522 Extension package for @code{hpcguix-web}.
21524 @item @code{menu} (default: @code{'()})
21525 Additional entry in page @code{menu}.
21527 @item @code{channels} (default: @code{%default-channels})
21528 List of channels from which the package list is built (@pxref{Channels}).
21530 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
21531 The expiration time, in seconds, after which the package list is rebuilt from
21532 the latest instances of the given channels.
21535 See the hpcguix-web repository for a
21536 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
21539 @item @code{package} (default: @code{hpcguix-web})
21540 The hpcguix-web package to use.
21544 A typical hpcguix-web service declaration looks like this:
21547 (service hpcguix-web-service-type
21548 (hpcguix-web-configuration
21550 #~(define site-config
21551 (hpcweb-configuration
21552 (title-prefix "Guix-HPC - ")
21553 (menu '(("/about" "ABOUT"))))))))
21557 The hpcguix-web service periodically updates the package list it publishes by
21558 pulling channels from Git. To that end, it needs to access X.509 certificates
21559 so that it can authenticate Git servers when communicating over HTTPS, and it
21560 assumes that @file{/etc/ssl/certs} contains those certificates.
21562 Thus, make sure to add @code{nss-certs} or another certificate package to the
21563 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
21564 more information on X.509 certificates.
21567 @node Certificate Services
21568 @subsection Certificate Services
21571 @cindex HTTP, HTTPS
21572 @cindex Let's Encrypt
21573 @cindex TLS certificates
21574 The @code{(gnu services certbot)} module provides a service to
21575 automatically obtain a valid TLS certificate from the Let's Encrypt
21576 certificate authority. These certificates can then be used to serve
21577 content securely over HTTPS or other TLS-based protocols, with the
21578 knowledge that the client will be able to verify the server's
21581 @url{https://letsencrypt.org/, Let's Encrypt} provides the
21582 @code{certbot} tool to automate the certification process. This tool
21583 first securely generates a key on the server. It then makes a request
21584 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
21585 checks that the request originates from the host in question by using a
21586 challenge-response protocol, requiring the server to provide its
21587 response over HTTP. If that protocol completes successfully, the CA
21588 signs the key, resulting in a certificate. That certificate is valid
21589 for a limited period of time, and therefore to continue to provide TLS
21590 services, the server needs to periodically ask the CA to renew its
21593 The certbot service automates this process: the initial key
21594 generation, the initial certification request to the Let's Encrypt
21595 service, the web server challenge/response integration, writing the
21596 certificate to disk, the automated periodic renewals, and the deployment
21597 tasks associated with the renewal (e.g.@: reloading services, copying keys
21598 with different permissions).
21600 Certbot is run twice a day, at a random minute within the hour. It
21601 won't do anything until your certificates are due for renewal or
21602 revoked, but running it regularly would give your service a chance of
21603 staying online in case a Let's Encrypt-initiated revocation happened for
21606 By using this service, you agree to the ACME Subscriber Agreement, which
21607 can be found there:
21608 @url{https://acme-v01.api.letsencrypt.org/directory}.
21610 @defvr {Scheme Variable} certbot-service-type
21611 A service type for the @code{certbot} Let's Encrypt client. Its value
21612 must be a @code{certbot-configuration} record as in this example:
21615 (define %nginx-deploy-hook
21617 "nginx-deploy-hook"
21618 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
21619 (kill pid SIGHUP))))
21621 (service certbot-service-type
21622 (certbot-configuration
21623 (email "foo@@example.net")
21626 (certificate-configuration
21627 (domains '("example.net" "www.example.net"))
21628 (deploy-hook %nginx-deploy-hook))
21629 (certificate-configuration
21630 (domains '("bar.example.net")))))))
21633 See below for details about @code{certbot-configuration}.
21636 @deftp {Data Type} certbot-configuration
21637 Data type representing the configuration of the @code{certbot} service.
21638 This type has the following parameters:
21641 @item @code{package} (default: @code{certbot})
21642 The certbot package to use.
21644 @item @code{webroot} (default: @code{/var/www})
21645 The directory from which to serve the Let's Encrypt challenge/response
21648 @item @code{certificates} (default: @code{()})
21649 A list of @code{certificates-configuration}s for which to generate
21650 certificates and request signatures. Each certificate has a @code{name}
21651 and several @code{domains}.
21654 Mandatory email used for registration, recovery contact, and important
21655 account notifications.
21657 @item @code{server} (default: @code{#f})
21658 Optional URL of ACME server. Setting this overrides certbot's default,
21659 which is the Let's Encrypt server.
21661 @item @code{rsa-key-size} (default: @code{2048})
21662 Size of the RSA key.
21664 @item @code{default-location} (default: @i{see below})
21665 The default @code{nginx-location-configuration}. Because @code{certbot}
21666 needs to be able to serve challenges and responses, it needs to be able
21667 to run a web server. It does so by extending the @code{nginx} web
21668 service with an @code{nginx-server-configuration} listening on the
21669 @var{domains} on port 80, and which has a
21670 @code{nginx-location-configuration} for the @code{/.well-known/} URI
21671 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
21672 these nginx configuration data types.
21674 Requests to other URL paths will be matched by the
21675 @code{default-location}, which if present is added to all
21676 @code{nginx-server-configuration}s.
21678 By default, the @code{default-location} will issue a redirect from
21679 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
21680 you to define what to serve on your site via @code{https}.
21682 Pass @code{#f} to not issue a default location.
21686 @deftp {Data Type} certificate-configuration
21687 Data type representing the configuration of a certificate.
21688 This type has the following parameters:
21691 @item @code{name} (default: @i{see below})
21692 This name is used by Certbot for housekeeping and in file paths; it
21693 doesn't affect the content of the certificate itself. To see
21694 certificate names, run @code{certbot certificates}.
21696 Its default is the first provided domain.
21698 @item @code{domains} (default: @code{()})
21699 The first domain provided will be the subject CN of the certificate, and
21700 all domains will be Subject Alternative Names on the certificate.
21702 @item @code{challenge} (default: @code{#f})
21703 The challenge type that has to be run by certbot. If @code{#f} is specified,
21704 default to the HTTP challenge. If a value is specified, defaults to the
21705 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
21706 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
21707 and gives Let's Encrypt permission to log the public IP address of the
21708 requesting machine.
21710 @item @code{authentication-hook} (default: @code{#f})
21711 Command to be run in a shell once for each certificate challenge to be
21712 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
21713 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
21714 contains the validation string and @code{$CERTBOT_TOKEN} contains the
21715 file name of the resource requested when performing an HTTP-01 challenge.
21717 @item @code{cleanup-hook} (default: @code{#f})
21718 Command to be run in a shell once for each certificate challenge that
21719 have been answered by the @code{auth-hook}. For this command, the shell
21720 variables available in the @code{auth-hook} script are still available, and
21721 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
21722 of the @code{auth-hook} script.
21724 @item @code{deploy-hook} (default: @code{#f})
21725 Command to be run in a shell once for each successfully issued
21726 certificate. For this command, the shell variable
21727 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
21728 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
21729 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
21730 contain a space-delimited list of renewed certificate domains (for
21731 example, @samp{"example.com www.example.com"}.
21736 For each @code{certificate-configuration}, the certificate is saved to
21737 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
21738 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
21740 @subsection DNS Services
21741 @cindex DNS (domain name system)
21742 @cindex domain name system (DNS)
21744 The @code{(gnu services dns)} module provides services related to the
21745 @dfn{domain name system} (DNS). It provides a server service for hosting
21746 an @emph{authoritative} DNS server for multiple zones, slave or master.
21747 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
21748 caching and forwarding DNS server for the LAN, which uses
21749 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
21751 @subsubheading Knot Service
21753 An example configuration of an authoritative server for two zones, one master
21757 (define-zone-entries example.org.zone
21758 ;; Name TTL Class Type Data
21759 ("@@" "" "IN" "A" "127.0.0.1")
21760 ("@@" "" "IN" "NS" "ns")
21761 ("ns" "" "IN" "A" "127.0.0.1"))
21763 (define master-zone
21764 (knot-zone-configuration
21765 (domain "example.org")
21767 (origin "example.org")
21768 (entries example.org.zone)))))
21771 (knot-zone-configuration
21772 (domain "plop.org")
21773 (dnssec-policy "default")
21774 (master (list "plop-master"))))
21776 (define plop-master
21777 (knot-remote-configuration
21779 (address (list "208.76.58.171"))))
21783 (services (cons* (service knot-service-type
21784 (knot-configuration
21785 (remotes (list plop-master))
21786 (zones (list master-zone slave-zone))))
21791 @deffn {Scheme Variable} knot-service-type
21792 This is the type for the Knot DNS server.
21794 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
21795 zones, that is to say domain names you would buy from a registrar. This server
21796 is not a resolver, meaning that it can only resolve names for which it is
21797 authoritative. This server can be configured to serve zones as a master server
21798 or a slave server as a per-zone basis. Slave zones will get their data from
21799 masters, and will serve it as an authoritative server. From the point of view
21800 of a resolver, there is no difference between master and slave.
21802 The following data types are used to configure the Knot DNS server:
21805 @deftp {Data Type} knot-key-configuration
21806 Data type representing a key.
21807 This type has the following parameters:
21810 @item @code{id} (default: @code{""})
21811 An identifier for other configuration fields to refer to this key. IDs must
21812 be unique and must not be empty.
21814 @item @code{algorithm} (default: @code{#f})
21815 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
21816 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
21817 and @code{'hmac-sha512}.
21819 @item @code{secret} (default: @code{""})
21820 The secret key itself.
21825 @deftp {Data Type} knot-acl-configuration
21826 Data type representing an Access Control List (ACL) configuration.
21827 This type has the following parameters:
21830 @item @code{id} (default: @code{""})
21831 An identifier for ether configuration fields to refer to this key. IDs must be
21832 unique and must not be empty.
21834 @item @code{address} (default: @code{'()})
21835 An ordered list of IP addresses, network subnets, or network ranges represented
21836 with strings. The query must match one of them. Empty value means that
21837 address match is not required.
21839 @item @code{key} (default: @code{'()})
21840 An ordered list of references to keys represented with strings. The string
21841 must match a key ID defined in a @code{knot-key-configuration}. No key means
21842 that a key is not require to match that ACL.
21844 @item @code{action} (default: @code{'()})
21845 An ordered list of actions that are permitted or forbidden by this ACL. Possible
21846 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
21847 and @code{'update}.
21849 @item @code{deny?} (default: @code{#f})
21850 When true, the ACL defines restrictions. Listed actions are forbidden. When
21851 false, listed actions are allowed.
21856 @deftp {Data Type} zone-entry
21857 Data type representing a record entry in a zone file.
21858 This type has the following parameters:
21861 @item @code{name} (default: @code{"@@"})
21862 The name of the record. @code{"@@"} refers to the origin of the zone. Names
21863 are relative to the origin of the zone. For example, in the @code{example.org}
21864 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
21865 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
21866 refers to @code{ns.example.org}.
21868 @item @code{ttl} (default: @code{""})
21869 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
21871 @item @code{class} (default: @code{"IN"})
21872 The class of the record. Knot currently supports only @code{"IN"} and
21873 partially @code{"CH"}.
21875 @item @code{type} (default: @code{"A"})
21876 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
21877 address), NS (Name Server) and MX (Mail eXchange). Many other types are
21880 @item @code{data} (default: @code{""})
21881 The data contained in the record. For instance an IP address associated with
21882 an A record, or a domain name associated with an NS record. Remember that
21883 domain names are relative to the origin unless they end with a dot.
21888 @deftp {Data Type} zone-file
21889 Data type representing the content of a zone file.
21890 This type has the following parameters:
21893 @item @code{entries} (default: @code{'()})
21894 The list of entries. The SOA record is taken care of, so you don't need to
21895 put it in the list of entries. This list should probably contain an entry
21896 for your primary authoritative DNS server. Other than using a list of entries
21897 directly, you can use @code{define-zone-entries} to define a object containing
21898 the list of entries more easily, that you can later pass to the @code{entries}
21899 field of the @code{zone-file}.
21901 @item @code{origin} (default: @code{""})
21902 The name of your zone. This parameter cannot be empty.
21904 @item @code{ns} (default: @code{"ns"})
21905 The domain of your primary authoritative DNS server. The name is relative to
21906 the origin, unless it ends with a dot. It is mandatory that this primary
21907 DNS server corresponds to an NS record in the zone and that it is associated
21908 to an IP address in the list of entries.
21910 @item @code{mail} (default: @code{"hostmaster"})
21911 An email address people can contact you at, as the owner of the zone. This
21912 is translated as @code{<mail>@@<origin>}.
21914 @item @code{serial} (default: @code{1})
21915 The serial number of the zone. As this is used to keep track of changes by
21916 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
21917 Always increment it when you make a change in your zone.
21919 @item @code{refresh} (default: @code{(* 2 24 3600)})
21920 The frequency at which slaves will do a zone transfer. This value is a number
21921 of seconds. It can be computed by multiplications or with
21922 @code{(string->duration)}.
21924 @item @code{retry} (default: @code{(* 15 60)})
21925 The period after which a slave will retry to contact its master when it fails
21926 to do so a first time.
21928 @item @code{expiry} (default: @code{(* 14 24 3600)})
21929 Default TTL of records. Existing records are considered correct for at most
21930 this amount of time. After this period, resolvers will invalidate their cache
21931 and check again that it still exists.
21933 @item @code{nx} (default: @code{3600})
21934 Default TTL of inexistant records. This delay is usually short because you want
21935 your new domains to reach everyone quickly.
21940 @deftp {Data Type} knot-remote-configuration
21941 Data type representing a remote configuration.
21942 This type has the following parameters:
21945 @item @code{id} (default: @code{""})
21946 An identifier for other configuration fields to refer to this remote. IDs must
21947 be unique and must not be empty.
21949 @item @code{address} (default: @code{'()})
21950 An ordered list of destination IP addresses. Addresses are tried in sequence.
21951 An optional port can be given with the @@ separator. For instance:
21952 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
21954 @item @code{via} (default: @code{'()})
21955 An ordered list of source IP addresses. An empty list will have Knot choose
21956 an appropriate source IP. An optional port can be given with the @@ separator.
21957 The default is to choose at random.
21959 @item @code{key} (default: @code{#f})
21960 A reference to a key, that is a string containing the identifier of a key
21961 defined in a @code{knot-key-configuration} field.
21966 @deftp {Data Type} knot-keystore-configuration
21967 Data type representing a keystore to hold dnssec keys.
21968 This type has the following parameters:
21971 @item @code{id} (default: @code{""})
21972 The id of the keystore. It must not be empty.
21974 @item @code{backend} (default: @code{'pem})
21975 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
21977 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
21978 The configuration string of the backend. An example for the PKCS#11 is:
21979 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
21980 For the pem backend, the string represents a path in the file system.
21985 @deftp {Data Type} knot-policy-configuration
21986 Data type representing a dnssec policy. Knot DNS is able to automatically
21987 sign your zones. It can either generate and manage your keys automatically or
21988 use keys that you generate.
21990 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
21991 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
21992 zone. In order to be trusted, the KSK needs to be present in the parent zone
21993 (usually a top-level domain). If your registrar supports dnssec, you will
21994 have to send them your KSK's hash so they can add a DS record in their zone.
21995 This is not automated and need to be done each time you change your KSK.
21997 The policy also defines the lifetime of keys. Usually, ZSK can be changed
21998 easily and use weaker cryptographic functions (they use lower parameters) in
21999 order to sign records quickly, so they are changed often. The KSK however
22000 requires manual interaction with the registrar, so they are changed less often
22001 and use stronger parameters because they sign only one record.
22003 This type has the following parameters:
22006 @item @code{id} (default: @code{""})
22007 The id of the policy. It must not be empty.
22009 @item @code{keystore} (default: @code{"default"})
22010 A reference to a keystore, that is a string containing the identifier of a
22011 keystore defined in a @code{knot-keystore-configuration} field. The
22012 @code{"default"} identifier means the default keystore (a kasp database that
22013 was setup by this service).
22015 @item @code{manual?} (default: @code{#f})
22016 Whether the key management is manual or automatic.
22018 @item @code{single-type-signing?} (default: @code{#f})
22019 When @code{#t}, use the Single-Type Signing Scheme.
22021 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
22022 An algorithm of signing keys and issued signatures.
22024 @item @code{ksk-size} (default: @code{256})
22025 The length of the KSK. Note that this value is correct for the default
22026 algorithm, but would be unsecure for other algorithms.
22028 @item @code{zsk-size} (default: @code{256})
22029 The length of the ZSK. Note that this value is correct for the default
22030 algorithm, but would be unsecure for other algorithms.
22032 @item @code{dnskey-ttl} (default: @code{'default})
22033 The TTL value for DNSKEY records added into zone apex. The special
22034 @code{'default} value means same as the zone SOA TTL.
22036 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
22037 The period between ZSK publication and the next rollover initiation.
22039 @item @code{propagation-delay} (default: @code{(* 24 3600)})
22040 An extra delay added for each key rollover step. This value should be high
22041 enough to cover propagation of data from the master server to all slaves.
22043 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
22044 A validity period of newly issued signatures.
22046 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
22047 A period how long before a signature expiration the signature will be refreshed.
22049 @item @code{nsec3?} (default: @code{#f})
22050 When @code{#t}, NSEC3 will be used instead of NSEC.
22052 @item @code{nsec3-iterations} (default: @code{5})
22053 The number of additional times the hashing is performed.
22055 @item @code{nsec3-salt-length} (default: @code{8})
22056 The length of a salt field in octets, which is appended to the original owner
22057 name before hashing.
22059 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
22060 The validity period of newly issued salt field.
22065 @deftp {Data Type} knot-zone-configuration
22066 Data type representing a zone served by Knot.
22067 This type has the following parameters:
22070 @item @code{domain} (default: @code{""})
22071 The domain served by this configuration. It must not be empty.
22073 @item @code{file} (default: @code{""})
22074 The file where this zone is saved. This parameter is ignored by master zones.
22075 Empty means default location that depends on the domain name.
22077 @item @code{zone} (default: @code{(zone-file)})
22078 The content of the zone file. This parameter is ignored by slave zones. It
22079 must contain a zone-file record.
22081 @item @code{master} (default: @code{'()})
22082 A list of master remotes. When empty, this zone is a master. When set, this
22083 zone is a slave. This is a list of remotes identifiers.
22085 @item @code{ddns-master} (default: @code{#f})
22086 The main master. When empty, it defaults to the first master in the list of
22089 @item @code{notify} (default: @code{'()})
22090 A list of slave remote identifiers.
22092 @item @code{acl} (default: @code{'()})
22093 A list of acl identifiers.
22095 @item @code{semantic-checks?} (default: @code{#f})
22096 When set, this adds more semantic checks to the zone.
22098 @item @code{disable-any?} (default: @code{#f})
22099 When set, this forbids queries of the ANY type.
22101 @item @code{zonefile-sync} (default: @code{0})
22102 The delay between a modification in memory and on disk. 0 means immediate
22105 @item @code{zonefile-load} (default: @code{#f})
22106 The way the zone file contents are applied during zone load. Possible values
22110 @item @code{#f} for using the default value from Knot,
22111 @item @code{'none} for not using the zone file at all,
22112 @item @code{'difference} for computing the difference between already available
22113 contents and zone contents and applying it to the current zone contents,
22114 @item @code{'difference-no-serial} for the same as @code{'difference}, but
22115 ignoring the SOA serial in the zone file, while the server takes care of it
22117 @item @code{'whole} for loading zone contents from the zone file.
22120 @item @code{journal-content} (default: @code{#f})
22121 The way the journal is used to store zone and its changes. Possible values
22122 are @code{'none} to not use it at all, @code{'changes} to store changes and
22123 @code{'all} to store contents. @code{#f} does not set this option, so the
22124 default value from Knot is used.
22126 @item @code{max-journal-usage} (default: @code{#f})
22127 The maximum size for the journal on disk. @code{#f} does not set this option,
22128 so the default value from Knot is used.
22130 @item @code{max-journal-depth} (default: @code{#f})
22131 The maximum size of the history. @code{#f} does not set this option, so the
22132 default value from Knot is used.
22134 @item @code{max-zone-size} (default: @code{#f})
22135 The maximum size of the zone file. This limit is enforced for incoming
22136 transfer and updates. @code{#f} does not set this option, so the default
22137 value from Knot is used.
22139 @item @code{dnssec-policy} (default: @code{#f})
22140 A reference to a @code{knot-policy-configuration} record, or the special
22141 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
22144 @item @code{serial-policy} (default: @code{'increment})
22145 A policy between @code{'increment} and @code{'unixtime}.
22150 @deftp {Data Type} knot-configuration
22151 Data type representing the Knot configuration.
22152 This type has the following parameters:
22155 @item @code{knot} (default: @code{knot})
22158 @item @code{run-directory} (default: @code{"/var/run/knot"})
22159 The run directory. This directory will be used for pid file and sockets.
22161 @item @code{includes} (default: @code{'()})
22162 A list of strings or file-like objects denoting other files that must be
22163 included at the top of the configuration file.
22165 @cindex secrets, Knot service
22166 This can be used to manage secrets out-of-band. For example, secret
22167 keys may be stored in an out-of-band file not managed by Guix, and
22168 thus not visible in @file{/gnu/store}---e.g., you could store secret
22169 key configuration in @file{/etc/knot/secrets.conf} and add this file
22170 to the @code{includes} list.
22172 One can generate a secret tsig key (for nsupdate and zone transfers with the
22173 keymgr command from the knot package. Note that the package is not automatically
22174 installed by the service. The following example shows how to generate a new
22178 keymgr -t mysecret > /etc/knot/secrets.conf
22179 chmod 600 /etc/knot/secrets.conf
22182 Also note that the generated key will be named @var{mysecret}, so it is the
22183 name that needs to be used in the @var{key} field of the
22184 @code{knot-acl-configuration} record and in other places that need to refer
22187 It can also be used to add configuration not supported by this interface.
22189 @item @code{listen-v4} (default: @code{"0.0.0.0"})
22190 An ip address on which to listen.
22192 @item @code{listen-v6} (default: @code{"::"})
22193 An ip address on which to listen.
22195 @item @code{listen-port} (default: @code{53})
22196 A port on which to listen.
22198 @item @code{keys} (default: @code{'()})
22199 The list of knot-key-configuration used by this configuration.
22201 @item @code{acls} (default: @code{'()})
22202 The list of knot-acl-configuration used by this configuration.
22204 @item @code{remotes} (default: @code{'()})
22205 The list of knot-remote-configuration used by this configuration.
22207 @item @code{zones} (default: @code{'()})
22208 The list of knot-zone-configuration used by this configuration.
22213 @subsubheading Knot Resolver Service
22215 @deffn {Scheme Variable} knot-resolver-service-type
22216 This this the type of the knot resolver service, whose value should be
22217 an @code{knot-resolver-configuration} object as in this example:
22220 (service knot-resolver-service-type
22221 (knot-resolver-configuration
22222 (kresd-config-file (plain-file "kresd.conf" "
22223 net.listen('192.168.0.1', 5353)
22224 user('knot-resolver', 'knot-resolver')
22225 modules = @{ 'hints > iterate', 'stats', 'predict' @}
22226 cache.size = 100 * MB
22230 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
22233 @deftp {Data Type} knot-resolver-configuration
22234 Data type representing the configuration of knot-resolver.
22237 @item @code{package} (default: @var{knot-resolver})
22238 Package object of the knot DNS resolver.
22240 @item @code{kresd-config-file} (default: %kresd.conf)
22241 File-like object of the kresd configuration file to use, by default it
22242 will listen on @code{127.0.0.1} and @code{::1}.
22244 @item @code{garbage-collection-interval} (default: 1000)
22245 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
22251 @subsubheading Dnsmasq Service
22253 @deffn {Scheme Variable} dnsmasq-service-type
22254 This is the type of the dnsmasq service, whose value should be an
22255 @code{dnsmasq-configuration} object as in this example:
22258 (service dnsmasq-service-type
22259 (dnsmasq-configuration
22261 (servers '("192.168.1.1"))))
22265 @deftp {Data Type} dnsmasq-configuration
22266 Data type representing the configuration of dnsmasq.
22269 @item @code{package} (default: @var{dnsmasq})
22270 Package object of the dnsmasq server.
22272 @item @code{no-hosts?} (default: @code{#f})
22273 When true, don't read the hostnames in /etc/hosts.
22275 @item @code{port} (default: @code{53})
22276 The port to listen on. Setting this to zero completely disables DNS
22277 responses, leaving only DHCP and/or TFTP functions.
22279 @item @code{local-service?} (default: @code{#t})
22280 Accept DNS queries only from hosts whose address is on a local subnet,
22281 ie a subnet for which an interface exists on the server.
22283 @item @code{listen-addresses} (default: @code{'()})
22284 Listen on the given IP addresses.
22286 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
22287 The file to read the IP address of the upstream nameservers from.
22289 @item @code{no-resolv?} (default: @code{#f})
22290 When true, don't read @var{resolv-file}.
22292 @item @code{servers} (default: @code{'()})
22293 Specify IP address of upstream servers directly.
22295 @item @code{addresses} (default: @code{'()})
22296 For each entry, specify an IP address to return for any host in the
22297 given domains. Queries in the domains are never forwarded and always
22298 replied to with the specified IP address.
22300 This is useful for redirecting hosts locally, for example:
22303 (service dnsmasq-service-type
22304 (dnsmasq-configuration
22306 '(; Redirect to a local web-server.
22307 "/example.org/127.0.0.1"
22308 ; Redirect subdomain to a specific IP.
22309 "/subdomain.example.org/192.168.1.42"))))
22312 Note that rules in @file{/etc/hosts} take precedence over this.
22314 @item @code{cache-size} (default: @code{150})
22315 Set the size of dnsmasq's cache. Setting the cache size to zero
22318 @item @code{negative-cache?} (default: @code{#t})
22319 When false, disable negative caching.
22324 @subsubheading ddclient Service
22327 The ddclient service described below runs the ddclient daemon, which takes
22328 care of automatically updating DNS entries for service providers such as
22329 @uref{https://dyn.com/dns/, Dyn}.
22331 The following example show instantiates the service with its default
22335 (service ddclient-service-type)
22338 Note that ddclient needs to access credentials that are stored in a
22339 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
22340 @code{secret-file} below). You are expected to create this file manually, in
22341 an ``out-of-band'' fashion (you @emph{could} make this file part of the
22342 service configuration, for instance by using @code{plain-file}, but it will be
22343 world-readable @i{via} @file{/gnu/store}). See the examples in the
22344 @file{share/ddclient} directory of the @code{ddclient} package.
22346 @c %start of fragment
22348 Available @code{ddclient-configuration} fields are:
22350 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
22351 The ddclient package.
22355 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
22356 The period after which ddclient will retry to check IP and domain name.
22358 Defaults to @samp{300}.
22362 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
22363 Use syslog for the output.
22365 Defaults to @samp{#t}.
22369 @deftypevr {@code{ddclient-configuration} parameter} string mail
22372 Defaults to @samp{"root"}.
22376 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
22377 Mail failed update to user.
22379 Defaults to @samp{"root"}.
22383 @deftypevr {@code{ddclient-configuration} parameter} string pid
22384 The ddclient PID file.
22386 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
22390 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
22391 Enable SSL support.
22393 Defaults to @samp{#t}.
22397 @deftypevr {@code{ddclient-configuration} parameter} string user
22398 Specifies the user name or ID that is used when running ddclient
22401 Defaults to @samp{"ddclient"}.
22405 @deftypevr {@code{ddclient-configuration} parameter} string group
22406 Group of the user who will run the ddclient program.
22408 Defaults to @samp{"ddclient"}.
22412 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
22413 Secret file which will be appended to @file{ddclient.conf} file. This
22414 file contains credentials for use by ddclient. You are expected to
22415 create it manually.
22417 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
22421 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
22422 Extra options will be appended to @file{ddclient.conf} file.
22424 Defaults to @samp{()}.
22429 @c %end of fragment
22433 @subsection VPN Services
22434 @cindex VPN (virtual private network)
22435 @cindex virtual private network (VPN)
22437 The @code{(gnu services vpn)} module provides services related to
22438 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
22439 your machine to connect to a VPN, and a @emph{server} service for your machine
22440 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
22442 @deffn {Scheme Procedure} openvpn-client-service @
22443 [#:config (openvpn-client-configuration)]
22445 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
22448 @deffn {Scheme Procedure} openvpn-server-service @
22449 [#:config (openvpn-server-configuration)]
22451 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
22453 Both can be run simultaneously.
22456 @c %automatically generated documentation
22458 Available @code{openvpn-client-configuration} fields are:
22460 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
22461 The OpenVPN package.
22465 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
22466 The OpenVPN pid file.
22468 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22472 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
22473 The protocol (UDP or TCP) used to open a channel between clients and
22476 Defaults to @samp{udp}.
22480 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
22481 The device type used to represent the VPN connection.
22483 Defaults to @samp{tun}.
22487 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
22488 The certificate authority to check connections against.
22490 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22494 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
22495 The certificate of the machine the daemon is running on. It should be
22496 signed by the authority given in @code{ca}.
22498 Defaults to @samp{"/etc/openvpn/client.crt"}.
22502 @deftypevr {@code{openvpn-client-configuration} parameter} string key
22503 The key of the machine the daemon is running on. It must be the key whose
22504 certificate is @code{cert}.
22506 Defaults to @samp{"/etc/openvpn/client.key"}.
22510 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
22511 Whether to use the lzo compression algorithm.
22513 Defaults to @samp{#t}.
22517 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
22518 Don't re-read key files across SIGUSR1 or --ping-restart.
22520 Defaults to @samp{#t}.
22524 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
22525 Don't close and reopen TUN/TAP device or run up/down scripts across
22526 SIGUSR1 or --ping-restart restarts.
22528 Defaults to @samp{#t}.
22532 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
22533 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22534 poll/epoll/select prior to the write operation.
22536 Defaults to @samp{#f}.
22539 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
22542 Defaults to @samp{3}.
22546 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
22547 Add an additional layer of HMAC authentication on top of the TLS control
22548 channel to protect against DoS attacks.
22550 Defaults to @samp{#f}.
22554 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
22555 Authenticate with server using username/password. The option is a file
22556 containing username/password on 2 lines. Do not use a file-like object as it
22557 would be added to the store and readable by any user.
22559 Defaults to @samp{'disabled}.
22562 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
22563 Whether to check the server certificate has server usage extension.
22565 Defaults to @samp{#t}.
22569 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
22570 Bind to a specific local port number.
22572 Defaults to @samp{#f}.
22576 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
22577 Retry resolving server address.
22579 Defaults to @samp{#t}.
22583 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
22584 A list of remote servers to connect to.
22586 Defaults to @samp{()}.
22588 Available @code{openvpn-remote-configuration} fields are:
22590 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
22593 Defaults to @samp{"my-server"}.
22597 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
22598 Port number the server listens to.
22600 Defaults to @samp{1194}.
22605 @c %end of automatic openvpn-client documentation
22607 @c %automatically generated documentation
22609 Available @code{openvpn-server-configuration} fields are:
22611 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
22612 The OpenVPN package.
22616 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
22617 The OpenVPN pid file.
22619 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22623 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
22624 The protocol (UDP or TCP) used to open a channel between clients and
22627 Defaults to @samp{udp}.
22631 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
22632 The device type used to represent the VPN connection.
22634 Defaults to @samp{tun}.
22638 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
22639 The certificate authority to check connections against.
22641 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22645 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
22646 The certificate of the machine the daemon is running on. It should be
22647 signed by the authority given in @code{ca}.
22649 Defaults to @samp{"/etc/openvpn/client.crt"}.
22653 @deftypevr {@code{openvpn-server-configuration} parameter} string key
22654 The key of the machine the daemon is running on. It must be the key whose
22655 certificate is @code{cert}.
22657 Defaults to @samp{"/etc/openvpn/client.key"}.
22661 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
22662 Whether to use the lzo compression algorithm.
22664 Defaults to @samp{#t}.
22668 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
22669 Don't re-read key files across SIGUSR1 or --ping-restart.
22671 Defaults to @samp{#t}.
22675 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
22676 Don't close and reopen TUN/TAP device or run up/down scripts across
22677 SIGUSR1 or --ping-restart restarts.
22679 Defaults to @samp{#t}.
22683 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
22684 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22685 poll/epoll/select prior to the write operation.
22687 Defaults to @samp{#f}.
22690 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
22693 Defaults to @samp{3}.
22697 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
22698 Add an additional layer of HMAC authentication on top of the TLS control
22699 channel to protect against DoS attacks.
22701 Defaults to @samp{#f}.
22705 @deftypevr {@code{openvpn-server-configuration} parameter} number port
22706 Specifies the port number on which the server listens.
22708 Defaults to @samp{1194}.
22712 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
22713 An ip and mask specifying the subnet inside the virtual network.
22715 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
22719 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
22720 A CIDR notation specifying the IPv6 subnet inside the virtual network.
22722 Defaults to @samp{#f}.
22726 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
22727 The Diffie-Hellman parameters file.
22729 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
22733 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
22734 The file that records client IPs.
22736 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
22740 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
22741 When true, the server will act as a gateway for its clients.
22743 Defaults to @samp{#f}.
22747 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
22748 When true, clients are allowed to talk to each other inside the VPN.
22750 Defaults to @samp{#f}.
22754 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
22755 Causes ping-like messages to be sent back and forth over the link so
22756 that each side knows when the other side has gone down. @code{keepalive}
22757 requires a pair. The first element is the period of the ping sending,
22758 and the second element is the timeout before considering the other side
22763 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
22764 The maximum number of clients.
22766 Defaults to @samp{100}.
22770 @deftypevr {@code{openvpn-server-configuration} parameter} string status
22771 The status file. This file shows a small report on current connection.
22772 It is truncated and rewritten every minute.
22774 Defaults to @samp{"/var/run/openvpn/status"}.
22778 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
22779 The list of configuration for some clients.
22781 Defaults to @samp{()}.
22783 Available @code{openvpn-ccd-configuration} fields are:
22785 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
22788 Defaults to @samp{"client"}.
22792 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
22795 Defaults to @samp{#f}.
22799 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
22802 Defaults to @samp{#f}.
22809 @c %end of automatic openvpn-server documentation
22812 @node Network File System
22813 @subsection Network File System
22816 The @code{(gnu services nfs)} module provides the following services,
22817 which are most commonly used in relation to mounting or exporting
22818 directory trees as @dfn{network file systems} (NFS).
22820 While it is possible to use the individual components that together make
22821 up a Network File System service, we recommended to configure an NFS
22822 server with the @code{nfs-service-type}.
22824 @subsubheading NFS Service
22825 @cindex NFS, server
22827 The NFS service takes care of setting up all NFS component services,
22828 kernel configuration file systems, and installs configuration files in
22829 the locations that NFS expects.
22831 @defvr {Scheme Variable} nfs-service-type
22832 A service type for a complete NFS server.
22835 @deftp {Data Type} nfs-configuration
22836 This data type represents the configuration of the NFS service and all
22839 It has the following parameters:
22841 @item @code{nfs-utils} (default: @code{nfs-utils})
22842 The nfs-utils package to use.
22844 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
22845 If a list of string values is provided, the @command{rpc.nfsd} daemon
22846 will be limited to supporting the given versions of the NFS protocol.
22848 @item @code{exports} (default: @code{'()})
22849 This is a list of directories the NFS server should export. Each entry
22850 is a list consisting of two elements: a directory name and a string
22851 containing all options. This is an example in which the directory
22852 @file{/export} is served to all NFS clients as a read-only share:
22858 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
22861 @item @code{rpcmountd-port} (default: @code{#f})
22862 The network port that the @command{rpc.mountd} daemon should use.
22864 @item @code{rpcstatd-port} (default: @code{#f})
22865 The network port that the @command{rpc.statd} daemon should use.
22867 @item @code{rpcbind} (default: @code{rpcbind})
22868 The rpcbind package to use.
22870 @item @code{idmap-domain} (default: @code{"localdomain"})
22871 The local NFSv4 domain name.
22873 @item @code{nfsd-port} (default: @code{2049})
22874 The network port that the @command{nfsd} daemon should use.
22876 @item @code{nfsd-threads} (default: @code{8})
22877 The number of threads used by the @command{nfsd} daemon.
22879 @item @code{nfsd-tcp?} (default: @code{#t})
22880 Whether the @command{nfsd} daemon should listen on a TCP socket.
22882 @item @code{nfsd-udp?} (default: @code{#f})
22883 Whether the @command{nfsd} daemon should listen on a UDP socket.
22885 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22886 The directory where the pipefs file system is mounted.
22888 @item @code{debug} (default: @code{'()"})
22889 A list of subsystems for which debugging output should be enabled. This
22890 is a list of symbols. Any of these symbols are valid: @code{nfsd},
22891 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
22895 If you don't need a complete NFS service or prefer to build it yourself
22896 you can use the individual component services that are documented below.
22898 @subsubheading RPC Bind Service
22901 The RPC Bind service provides a facility to map program numbers into
22902 universal addresses.
22903 Many NFS related services use this facility. Hence it is automatically
22904 started when a dependent service starts.
22906 @defvr {Scheme Variable} rpcbind-service-type
22907 A service type for the RPC portmapper daemon.
22911 @deftp {Data Type} rpcbind-configuration
22912 Data type representing the configuration of the RPC Bind Service.
22913 This type has the following parameters:
22915 @item @code{rpcbind} (default: @code{rpcbind})
22916 The rpcbind package to use.
22918 @item @code{warm-start?} (default: @code{#t})
22919 If this parameter is @code{#t}, then the daemon will read a
22920 state file on startup thus reloading state information saved by a previous
22926 @subsubheading Pipefs Pseudo File System
22930 The pipefs file system is used to transfer NFS related data
22931 between the kernel and user space programs.
22933 @defvr {Scheme Variable} pipefs-service-type
22934 A service type for the pipefs pseudo file system.
22937 @deftp {Data Type} pipefs-configuration
22938 Data type representing the configuration of the pipefs pseudo file system service.
22939 This type has the following parameters:
22941 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22942 The directory to which the file system is to be attached.
22947 @subsubheading GSS Daemon Service
22950 @cindex global security system
22952 The @dfn{global security system} (GSS) daemon provides strong security for RPC
22954 Before exchanging RPC requests an RPC client must establish a security
22955 context. Typically this is done using the Kerberos command @command{kinit}
22956 or automatically at login time using PAM services (@pxref{Kerberos Services}).
22958 @defvr {Scheme Variable} gss-service-type
22959 A service type for the Global Security System (GSS) daemon.
22962 @deftp {Data Type} gss-configuration
22963 Data type representing the configuration of the GSS daemon service.
22964 This type has the following parameters:
22966 @item @code{nfs-utils} (default: @code{nfs-utils})
22967 The package in which the @command{rpc.gssd} command is to be found.
22969 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22970 The directory where the pipefs file system is mounted.
22976 @subsubheading IDMAP Daemon Service
22978 @cindex name mapper
22980 The idmap daemon service provides mapping between user IDs and user names.
22981 Typically it is required in order to access file systems mounted via NFSv4.
22983 @defvr {Scheme Variable} idmap-service-type
22984 A service type for the Identity Mapper (IDMAP) daemon.
22987 @deftp {Data Type} idmap-configuration
22988 Data type representing the configuration of the IDMAP daemon service.
22989 This type has the following parameters:
22991 @item @code{nfs-utils} (default: @code{nfs-utils})
22992 The package in which the @command{rpc.idmapd} command is to be found.
22994 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22995 The directory where the pipefs file system is mounted.
22997 @item @code{domain} (default: @code{#f})
22998 The local NFSv4 domain name.
22999 This must be a string or @code{#f}.
23000 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
23002 @item @code{verbosity} (default: @code{0})
23003 The verbosity level of the daemon.
23008 @node Continuous Integration
23009 @subsection Continuous Integration
23011 @cindex continuous integration
23012 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
23013 continuous integration tool for Guix. It can be used both for development and
23014 for providing substitutes to others (@pxref{Substitutes}).
23016 The @code{(gnu services cuirass)} module provides the following service.
23018 @defvr {Scheme Procedure} cuirass-service-type
23019 The type of the Cuirass service. Its value must be a
23020 @code{cuirass-configuration} object, as described below.
23023 To add build jobs, you have to set the @code{specifications} field of the
23024 configuration. Here is an example of a service that polls the Guix repository
23025 and builds the packages from a manifest. Some of the packages are defined in
23026 the @code{"custom-packages"} input, which is the equivalent of
23027 @env{GUIX_PACKAGE_PATH}.
23030 (define %cuirass-specs
23032 '((#:name . "my-manifest")
23033 (#:load-path-inputs . ("guix"))
23034 (#:package-path-inputs . ("custom-packages"))
23035 (#:proc-input . "guix")
23036 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
23037 (#:proc . cuirass-jobs)
23038 (#:proc-args . ((subset . "manifests")
23039 (systems . ("x86_64-linux"))
23040 (manifests . (("config" . "guix/manifest.scm")))))
23041 (#:inputs . (((#:name . "guix")
23042 (#:url . "git://git.savannah.gnu.org/guix.git")
23043 (#:load-path . ".")
23044 (#:branch . "master")
23045 (#:no-compile? . #t))
23046 ((#:name . "config")
23047 (#:url . "https://git.example.org/config.git")
23048 (#:load-path . ".")
23049 (#:branch . "master")
23050 (#:no-compile? . #t))
23051 ((#:name . "custom-packages")
23052 (#:url . "https://git.example.org/custom-packages.git")
23053 (#:load-path . ".")
23054 (#:branch . "master")
23055 (#:no-compile? . #t)))))))
23057 (service cuirass-service-type
23058 (cuirass-configuration
23059 (specifications %cuirass-specs)))
23062 While information related to build jobs is located directly in the
23063 specifications, global settings for the @command{cuirass} process are
23064 accessible in other @code{cuirass-configuration} fields.
23066 @deftp {Data Type} cuirass-configuration
23067 Data type representing the configuration of Cuirass.
23070 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
23071 Location of the log file.
23073 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
23074 Location of the log file used by the web interface.
23076 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
23077 Location of the repository cache.
23079 @item @code{user} (default: @code{"cuirass"})
23080 Owner of the @code{cuirass} process.
23082 @item @code{group} (default: @code{"cuirass"})
23083 Owner's group of the @code{cuirass} process.
23085 @item @code{interval} (default: @code{60})
23086 Number of seconds between the poll of the repositories followed by the
23089 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
23090 Location of sqlite database which contains the build results and previously
23091 added specifications.
23093 @item @code{ttl} (default: @code{(* 30 24 3600)})
23094 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
23095 are registered for build results. This means that build results are protected
23096 from garbage collection for at least @var{ttl} seconds.
23098 @item @code{port} (default: @code{8081})
23099 Port number used by the HTTP server.
23101 @item @code{host} (default: @code{"localhost"})
23102 Listen on the network interface for @var{host}. The default is to
23103 accept connections from localhost.
23105 @item @code{specifications} (default: @code{#~'()})
23106 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
23107 where a specification is an association list
23108 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
23109 keys are keywords (@code{#:keyword-example}) as shown in the example
23112 @item @code{use-substitutes?} (default: @code{#f})
23113 This allows using substitutes to avoid building every dependencies of a job
23116 @item @code{one-shot?} (default: @code{#f})
23117 Only evaluate specifications and build derivations once.
23119 @item @code{fallback?} (default: @code{#f})
23120 When substituting a pre-built binary fails, fall back to building
23123 @item @code{extra-options} (default: @code{'()})
23124 Extra options to pass when running the Cuirass processes.
23126 @item @code{cuirass} (default: @code{cuirass})
23127 The Cuirass package to use.
23131 @node Power Management Services
23132 @subsection Power Management Services
23135 @cindex power management with TLP
23136 @subsubheading TLP daemon
23138 The @code{(gnu services pm)} module provides a Guix service definition
23139 for the Linux power management tool TLP.
23141 TLP enables various powersaving modes in userspace and kernel.
23142 Contrary to @code{upower-service}, it is not a passive,
23143 monitoring tool, as it will apply custom settings each time a new power
23144 source is detected. More information can be found at
23145 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
23147 @deffn {Scheme Variable} tlp-service-type
23148 The service type for the TLP tool. Its value should be a valid
23149 TLP configuration (see below). To use the default settings, simply
23152 (service tlp-service-type)
23156 By default TLP does not need much configuration but most TLP parameters
23157 can be tweaked using @code{tlp-configuration}.
23159 Each parameter definition is preceded by its type; for example,
23160 @samp{boolean foo} indicates that the @code{foo} parameter
23161 should be specified as a boolean. Types starting with
23162 @code{maybe-} denote parameters that won't show up in TLP config file
23163 when their value is @code{'disabled}.
23165 @c The following documentation was initially generated by
23166 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
23167 @c documentation is better, so we shouldn't hesitate to edit below as
23168 @c needed. However if the change you want to make to this documentation
23169 @c can be done in an automated way, it's probably easier to change
23170 @c (generate-documentation) than to make it below and have to deal with
23171 @c the churn as TLP updates.
23173 Available @code{tlp-configuration} fields are:
23175 @deftypevr {@code{tlp-configuration} parameter} package tlp
23180 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
23181 Set to true if you wish to enable TLP.
23183 Defaults to @samp{#t}.
23187 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
23188 Default mode when no power supply can be detected. Alternatives are AC
23191 Defaults to @samp{"AC"}.
23195 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
23196 Number of seconds Linux kernel has to wait after the disk goes idle,
23197 before syncing on AC.
23199 Defaults to @samp{0}.
23203 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
23204 Same as @code{disk-idle-ac} but on BAT mode.
23206 Defaults to @samp{2}.
23210 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
23211 Dirty pages flushing periodicity, expressed in seconds.
23213 Defaults to @samp{15}.
23217 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
23218 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
23220 Defaults to @samp{60}.
23224 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
23225 CPU frequency scaling governor on AC mode. With intel_pstate driver,
23226 alternatives are powersave and performance. With acpi-cpufreq driver,
23227 alternatives are ondemand, powersave, performance and conservative.
23229 Defaults to @samp{disabled}.
23233 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
23234 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
23236 Defaults to @samp{disabled}.
23240 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
23241 Set the min available frequency for the scaling governor on AC.
23243 Defaults to @samp{disabled}.
23247 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
23248 Set the max available frequency for the scaling governor on AC.
23250 Defaults to @samp{disabled}.
23254 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
23255 Set the min available frequency for the scaling governor on BAT.
23257 Defaults to @samp{disabled}.
23261 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
23262 Set the max available frequency for the scaling governor on BAT.
23264 Defaults to @samp{disabled}.
23268 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
23269 Limit the min P-state to control the power dissipation of the CPU, in AC
23270 mode. Values are stated as a percentage of the available performance.
23272 Defaults to @samp{disabled}.
23276 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
23277 Limit the max P-state to control the power dissipation of the CPU, in AC
23278 mode. Values are stated as a percentage of the available performance.
23280 Defaults to @samp{disabled}.
23284 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
23285 Same as @code{cpu-min-perf-on-ac} on BAT mode.
23287 Defaults to @samp{disabled}.
23291 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
23292 Same as @code{cpu-max-perf-on-ac} on BAT mode.
23294 Defaults to @samp{disabled}.
23298 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
23299 Enable CPU turbo boost feature on AC mode.
23301 Defaults to @samp{disabled}.
23305 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
23306 Same as @code{cpu-boost-on-ac?} on BAT mode.
23308 Defaults to @samp{disabled}.
23312 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
23313 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
23314 used under light load conditions.
23316 Defaults to @samp{#f}.
23320 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
23321 Same as @code{sched-powersave-on-ac?} but on BAT mode.
23323 Defaults to @samp{#t}.
23327 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
23328 Enable Linux kernel NMI watchdog.
23330 Defaults to @samp{#f}.
23334 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
23335 For Linux kernels with PHC patch applied, change CPU voltages. An
23336 example value would be @samp{"F:V F:V F:V F:V"}.
23338 Defaults to @samp{disabled}.
23342 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
23343 Set CPU performance versus energy saving policy on AC. Alternatives are
23344 performance, normal, powersave.
23346 Defaults to @samp{"performance"}.
23350 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
23351 Same as @code{energy-perf-policy-ac} but on BAT mode.
23353 Defaults to @samp{"powersave"}.
23357 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
23362 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
23363 Hard disk advanced power management level.
23367 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
23368 Same as @code{disk-apm-bat} but on BAT mode.
23372 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
23373 Hard disk spin down timeout. One value has to be specified for each
23374 declared hard disk.
23376 Defaults to @samp{disabled}.
23380 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
23381 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
23383 Defaults to @samp{disabled}.
23387 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
23388 Select IO scheduler for disk devices. One value has to be specified for
23389 each declared hard disk. Example alternatives are cfq, deadline and
23392 Defaults to @samp{disabled}.
23396 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
23397 SATA aggressive link power management (ALPM) level. Alternatives are
23398 min_power, medium_power, max_performance.
23400 Defaults to @samp{"max_performance"}.
23404 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
23405 Same as @code{sata-linkpwr-ac} but on BAT mode.
23407 Defaults to @samp{"min_power"}.
23411 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
23412 Exclude specified SATA host devices for link power management.
23414 Defaults to @samp{disabled}.
23418 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
23419 Enable Runtime Power Management for AHCI controller and disks on AC
23422 Defaults to @samp{disabled}.
23426 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
23427 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
23429 Defaults to @samp{disabled}.
23433 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
23434 Seconds of inactivity before disk is suspended.
23436 Defaults to @samp{15}.
23440 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
23441 PCI Express Active State Power Management level. Alternatives are
23442 default, performance, powersave.
23444 Defaults to @samp{"performance"}.
23448 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
23449 Same as @code{pcie-aspm-ac} but on BAT mode.
23451 Defaults to @samp{"powersave"}.
23455 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
23456 Radeon graphics clock speed level. Alternatives are low, mid, high,
23459 Defaults to @samp{"high"}.
23463 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
23464 Same as @code{radeon-power-ac} but on BAT mode.
23466 Defaults to @samp{"low"}.
23470 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
23471 Radeon dynamic power management method (DPM). Alternatives are battery,
23474 Defaults to @samp{"performance"}.
23478 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
23479 Same as @code{radeon-dpm-state-ac} but on BAT mode.
23481 Defaults to @samp{"battery"}.
23485 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
23486 Radeon DPM performance level. Alternatives are auto, low, high.
23488 Defaults to @samp{"auto"}.
23492 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
23493 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
23495 Defaults to @samp{"auto"}.
23499 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
23500 Wifi power saving mode.
23502 Defaults to @samp{#f}.
23506 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
23507 Same as @code{wifi-power-ac?} but on BAT mode.
23509 Defaults to @samp{#t}.
23513 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
23514 Disable wake on LAN.
23516 Defaults to @samp{#t}.
23520 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
23521 Timeout duration in seconds before activating audio power saving on
23522 Intel HDA and AC97 devices. A value of 0 disables power saving.
23524 Defaults to @samp{0}.
23528 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
23529 Same as @code{sound-powersave-ac} but on BAT mode.
23531 Defaults to @samp{1}.
23535 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
23536 Disable controller in powersaving mode on Intel HDA devices.
23538 Defaults to @samp{#t}.
23542 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
23543 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
23544 powered on again by releasing (and reinserting) the eject lever or by
23545 pressing the disc eject button on newer models.
23547 Defaults to @samp{#f}.
23551 @deftypevr {@code{tlp-configuration} parameter} string bay-device
23552 Name of the optical drive device to power off.
23554 Defaults to @samp{"sr0"}.
23558 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
23559 Runtime Power Management for PCI(e) bus devices. Alternatives are on
23562 Defaults to @samp{"on"}.
23566 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
23567 Same as @code{runtime-pm-ac} but on BAT mode.
23569 Defaults to @samp{"auto"}.
23573 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
23574 Runtime Power Management for all PCI(e) bus devices, except blacklisted
23577 Defaults to @samp{#t}.
23581 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
23582 Exclude specified PCI(e) device addresses from Runtime Power Management.
23584 Defaults to @samp{disabled}.
23588 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
23589 Exclude PCI(e) devices assigned to the specified drivers from Runtime
23594 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
23595 Enable USB autosuspend feature.
23597 Defaults to @samp{#t}.
23601 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
23602 Exclude specified devices from USB autosuspend.
23604 Defaults to @samp{disabled}.
23608 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
23609 Exclude WWAN devices from USB autosuspend.
23611 Defaults to @samp{#t}.
23615 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
23616 Include specified devices into USB autosuspend, even if they are already
23617 excluded by the driver or via @code{usb-blacklist-wwan?}.
23619 Defaults to @samp{disabled}.
23623 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
23624 Enable USB autosuspend before shutdown.
23626 Defaults to @samp{disabled}.
23630 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
23631 Restore radio device state (bluetooth, wifi, wwan) from previous
23632 shutdown on system startup.
23634 Defaults to @samp{#f}.
23639 @cindex CPU frequency scaling with thermald
23640 @subsubheading Thermald daemon
23642 The @code{(gnu services pm)} module provides an interface to
23643 thermald, a CPU frequency scaling service which helps prevent overheating.
23645 @defvr {Scheme Variable} thermald-service-type
23646 This is the service type for
23647 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
23648 Thermal Daemon, which is responsible for controlling the thermal state
23649 of processors and preventing overheating.
23652 @deftp {Data Type} thermald-configuration
23653 Data type representing the configuration of @code{thermald-service-type}.
23656 @item @code{ignore-cpuid-check?} (default: @code{#f})
23657 Ignore cpuid check for supported CPU models.
23659 @item @code{thermald} (default: @var{thermald})
23660 Package object of thermald.
23665 @node Audio Services
23666 @subsection Audio Services
23668 The @code{(gnu services audio)} module provides a service to start MPD
23669 (the Music Player Daemon).
23672 @subsubheading Music Player Daemon
23674 The Music Player Daemon (MPD) is a service that can play music while
23675 being controlled from the local machine or over the network by a variety
23678 The following example shows how one might run @code{mpd} as user
23679 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
23682 (service mpd-service-type
23688 @defvr {Scheme Variable} mpd-service-type
23689 The service type for @command{mpd}
23692 @deftp {Data Type} mpd-configuration
23693 Data type representing the configuration of @command{mpd}.
23696 @item @code{user} (default: @code{"mpd"})
23697 The user to run mpd as.
23699 @item @code{music-dir} (default: @code{"~/Music"})
23700 The directory to scan for music files.
23702 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
23703 The directory to store playlists.
23705 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
23706 The location of the music database.
23708 @item @code{state-file} (default: @code{"~/.mpd/state"})
23709 The location of the file that stores current MPD's state.
23711 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
23712 The location of the sticker database.
23714 @item @code{port} (default: @code{"6600"})
23715 The port to run mpd on.
23717 @item @code{address} (default: @code{"any"})
23718 The address that mpd will bind to. To use a Unix domain socket,
23719 an absolute path can be specified here.
23721 @item @code{outputs} (default: @code{"(list (mpd-output))"})
23722 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
23727 @deftp {Data Type} mpd-output
23728 Data type representing an @command{mpd} audio output.
23731 @item @code{name} (default: @code{"MPD"})
23732 The name of the audio output.
23734 @item @code{type} (default: @code{"pulse"})
23735 The type of audio output.
23737 @item @code{enabled?} (default: @code{#t})
23738 Specifies whether this audio output is enabled when MPD is started. By
23739 default, all audio outputs are enabled. This is just the default
23740 setting when there is no state file; with a state file, the previous
23743 @item @code{tags?} (default: @code{#t})
23744 If set to @code{#f}, then MPD will not send tags to this output. This
23745 is only useful for output plugins that can receive tags, for example the
23746 @code{httpd} output plugin.
23748 @item @code{always-on?} (default: @code{#f})
23749 If set to @code{#t}, then MPD attempts to keep this audio output always
23750 open. This may be useful for streaming servers, when you don’t want to
23751 disconnect all listeners even when playback is accidentally stopped.
23753 @item @code{mixer-type}
23754 This field accepts a symbol that specifies which mixer should be used
23755 for this audio output: the @code{hardware} mixer, the @code{software}
23756 mixer, the @code{null} mixer (allows setting the volume, but with no
23757 effect; this can be used as a trick to implement an external mixer
23758 External Mixer) or no mixer (@code{none}).
23760 @item @code{extra-options} (default: @code{'()"})
23761 An association list of option symbols to string values to be appended to
23762 the audio output configuration.
23767 The following example shows a configuration of @code{mpd} that provides
23768 an HTTP audio streaming output.
23771 (service mpd-service-type
23779 `((encoder . "vorbis")
23780 (port . "8080"))))))))
23784 @node Virtualization Services
23785 @subsection Virtualization services
23787 The @code{(gnu services virtualization)} module provides services for
23788 the libvirt and virtlog daemons, as well as other virtualization-related
23791 @subsubheading Libvirt daemon
23792 @code{libvirtd} is the server side daemon component of the libvirt
23793 virtualization management system. This daemon runs on host servers
23794 and performs required management tasks for virtualized guests.
23796 @deffn {Scheme Variable} libvirt-service-type
23797 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
23798 Its value must be a @code{libvirt-configuration}.
23801 (service libvirt-service-type
23802 (libvirt-configuration
23803 (unix-sock-group "libvirt")
23804 (tls-port "16555")))
23808 @c Auto-generated with (generate-libvirt-documentation)
23809 Available @code{libvirt-configuration} fields are:
23811 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
23816 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
23817 Flag listening for secure TLS connections on the public TCP/IP port.
23818 must set @code{listen} for this to have any effect.
23820 It is necessary to setup a CA and issue server certificates before using
23823 Defaults to @samp{#t}.
23827 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
23828 Listen for unencrypted TCP connections on the public TCP/IP port. must
23829 set @code{listen} for this to have any effect.
23831 Using the TCP socket requires SASL authentication by default. Only SASL
23832 mechanisms which support data encryption are allowed. This is
23833 DIGEST_MD5 and GSSAPI (Kerberos5)
23835 Defaults to @samp{#f}.
23839 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
23840 Port for accepting secure TLS connections This can be a port number, or
23843 Defaults to @samp{"16514"}.
23847 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
23848 Port for accepting insecure TCP connections This can be a port number,
23851 Defaults to @samp{"16509"}.
23855 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
23856 IP address or hostname used for client connections.
23858 Defaults to @samp{"0.0.0.0"}.
23862 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
23863 Flag toggling mDNS advertisement of the libvirt service.
23865 Alternatively can disable for all services on a host by stopping the
23868 Defaults to @samp{#f}.
23872 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
23873 Default mDNS advertisement name. This must be unique on the immediate
23876 Defaults to @samp{"Virtualization Host <hostname>"}.
23880 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
23881 UNIX domain socket group ownership. This can be used to allow a
23882 'trusted' set of users access to management capabilities without
23885 Defaults to @samp{"root"}.
23889 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
23890 UNIX socket permissions for the R/O socket. This is used for monitoring
23893 Defaults to @samp{"0777"}.
23897 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
23898 UNIX socket permissions for the R/W socket. Default allows only root.
23899 If PolicyKit is enabled on the socket, the default will change to allow
23900 everyone (eg, 0777)
23902 Defaults to @samp{"0770"}.
23906 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
23907 UNIX socket permissions for the admin socket. Default allows only owner
23908 (root), do not change it unless you are sure to whom you are exposing
23911 Defaults to @samp{"0777"}.
23915 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
23916 The directory in which sockets will be found/created.
23918 Defaults to @samp{"/var/run/libvirt"}.
23922 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
23923 Authentication scheme for UNIX read-only sockets. By default socket
23924 permissions allow anyone to connect
23926 Defaults to @samp{"polkit"}.
23930 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
23931 Authentication scheme for UNIX read-write sockets. By default socket
23932 permissions only allow root. If PolicyKit support was compiled into
23933 libvirt, the default will be to use 'polkit' auth.
23935 Defaults to @samp{"polkit"}.
23939 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
23940 Authentication scheme for TCP sockets. If you don't enable SASL, then
23941 all TCP traffic is cleartext. Don't do this outside of a dev/test
23944 Defaults to @samp{"sasl"}.
23948 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
23949 Authentication scheme for TLS sockets. TLS sockets already have
23950 encryption provided by the TLS layer, and limited authentication is done
23953 It is possible to make use of any SASL authentication mechanism as well,
23954 by using 'sasl' for this option
23956 Defaults to @samp{"none"}.
23960 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
23961 API access control scheme.
23963 By default an authenticated user is allowed access to all APIs. Access
23964 drivers can place restrictions on this.
23966 Defaults to @samp{()}.
23970 @deftypevr {@code{libvirt-configuration} parameter} string key-file
23971 Server key file path. If set to an empty string, then no private key is
23974 Defaults to @samp{""}.
23978 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
23979 Server key file path. If set to an empty string, then no certificate is
23982 Defaults to @samp{""}.
23986 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
23987 Server key file path. If set to an empty string, then no CA certificate
23990 Defaults to @samp{""}.
23994 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
23995 Certificate revocation list path. If set to an empty string, then no
23998 Defaults to @samp{""}.
24002 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
24003 Disable verification of our own server certificates.
24005 When libvirtd starts it performs some sanity checks against its own
24008 Defaults to @samp{#f}.
24012 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
24013 Disable verification of client certificates.
24015 Client certificate verification is the primary authentication mechanism.
24016 Any client which does not present a certificate signed by the CA will be
24019 Defaults to @samp{#f}.
24023 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
24024 Whitelist of allowed x509 Distinguished Name.
24026 Defaults to @samp{()}.
24030 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
24031 Whitelist of allowed SASL usernames. The format for username depends on
24032 the SASL authentication mechanism.
24034 Defaults to @samp{()}.
24038 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
24039 Override the compile time default TLS priority string. The default is
24040 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
24041 is desired for libvirt to deviate from the global default settings.
24043 Defaults to @samp{"NORMAL"}.
24047 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
24048 Maximum number of concurrent client connections to allow over all
24051 Defaults to @samp{5000}.
24055 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
24056 Maximum length of queue of connections waiting to be accepted by the
24057 daemon. Note, that some protocols supporting retransmission may obey
24058 this so that a later reattempt at connection succeeds.
24060 Defaults to @samp{1000}.
24064 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
24065 Maximum length of queue of accepted but not yet authenticated clients.
24066 Set this to zero to turn this feature off
24068 Defaults to @samp{20}.
24072 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
24073 Number of workers to start up initially.
24075 Defaults to @samp{5}.
24079 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
24080 Maximum number of worker threads.
24082 If the number of active clients exceeds @code{min-workers}, then more
24083 threads are spawned, up to max_workers limit. Typically you'd want
24084 max_workers to equal maximum number of clients allowed.
24086 Defaults to @samp{20}.
24090 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
24091 Number of priority workers. If all workers from above pool are stuck,
24092 some calls marked as high priority (notably domainDestroy) can be
24093 executed in this pool.
24095 Defaults to @samp{5}.
24099 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
24100 Total global limit on concurrent RPC calls.
24102 Defaults to @samp{20}.
24106 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
24107 Limit on concurrent requests from a single client connection. To avoid
24108 one client monopolizing the server this should be a small fraction of
24109 the global max_requests and max_workers parameter.
24111 Defaults to @samp{5}.
24115 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
24116 Same as @code{min-workers} but for the admin interface.
24118 Defaults to @samp{1}.
24122 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
24123 Same as @code{max-workers} but for the admin interface.
24125 Defaults to @samp{5}.
24129 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
24130 Same as @code{max-clients} but for the admin interface.
24132 Defaults to @samp{5}.
24136 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
24137 Same as @code{max-queued-clients} but for the admin interface.
24139 Defaults to @samp{5}.
24143 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
24144 Same as @code{max-client-requests} but for the admin interface.
24146 Defaults to @samp{5}.
24150 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
24151 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
24153 Defaults to @samp{3}.
24157 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
24160 A filter allows to select a different logging level for a given category
24161 of logs The format for a filter is one of:
24172 where @code{name} is a string which is matched against the category
24173 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
24174 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
24175 name in the filter can be a substring of the full category name, in
24176 order to match multiple similar categories), the optional @samp{"+"}
24177 prefix tells libvirt to log stack trace for each message matching name,
24178 and @code{x} is the minimal level where matching messages should be
24196 Multiple filters can be defined in a single filters statement, they just
24197 need to be separated by spaces.
24199 Defaults to @samp{"3:remote 4:event"}.
24203 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
24206 An output is one of the places to save logging information. The format
24207 for an output can be:
24211 output goes to stderr
24213 @item x:syslog:name
24214 use syslog for the output and use the given name as the ident
24216 @item x:file:file_path
24217 output to a file, with the given filepath
24220 output to journald logging system
24224 In all case the x prefix is the minimal level, acting as a filter
24241 Multiple outputs can be defined, they just need to be separated by
24244 Defaults to @samp{"3:stderr"}.
24248 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
24249 Allows usage of the auditing subsystem to be altered
24253 0: disable all auditing
24256 1: enable auditing, only if enabled on host
24259 2: enable auditing, and exit if disabled on host.
24263 Defaults to @samp{1}.
24267 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
24268 Send audit messages via libvirt logging infrastructure.
24270 Defaults to @samp{#f}.
24274 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
24275 Host UUID. UUID must not have all digits be the same.
24277 Defaults to @samp{""}.
24281 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
24282 Source to read host UUID.
24286 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
24289 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
24293 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
24296 Defaults to @samp{"smbios"}.
24300 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
24301 A keepalive message is sent to a client after @code{keepalive_interval}
24302 seconds of inactivity to check if the client is still responding. If
24303 set to -1, libvirtd will never send keepalive requests; however clients
24304 can still send them and the daemon will send responses.
24306 Defaults to @samp{5}.
24310 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
24311 Maximum number of keepalive messages that are allowed to be sent to the
24312 client without getting any response before the connection is considered
24315 In other words, the connection is automatically closed approximately
24316 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
24317 the last message received from the client. When @code{keepalive-count}
24318 is set to 0, connections will be automatically closed after
24319 @code{keepalive-interval} seconds of inactivity without sending any
24320 keepalive messages.
24322 Defaults to @samp{5}.
24326 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
24327 Same as above but for admin interface.
24329 Defaults to @samp{5}.
24333 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
24334 Same as above but for admin interface.
24336 Defaults to @samp{5}.
24340 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
24341 Timeout for Open vSwitch calls.
24343 The @code{ovs-vsctl} utility is used for the configuration and its
24344 timeout option is set by default to 5 seconds to avoid potential
24345 infinite waits blocking libvirt.
24347 Defaults to @samp{5}.
24351 @c %end of autogenerated docs
24353 @subsubheading Virtlog daemon
24354 The virtlogd service is a server side daemon component of libvirt that is
24355 used to manage logs from virtual machine consoles.
24357 This daemon is not used directly by libvirt client applications, rather it
24358 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
24359 standalone daemon, the main @code{libvirtd} daemon can be restarted without
24360 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
24361 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
24363 @deffn {Scheme Variable} virtlog-service-type
24364 This is the type of the virtlog daemon.
24365 Its value must be a @code{virtlog-configuration}.
24368 (service virtlog-service-type
24369 (virtlog-configuration
24370 (max-clients 1000)))
24374 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
24375 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
24377 Defaults to @samp{3}.
24381 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
24384 A filter allows to select a different logging level for a given category
24385 of logs The format for a filter is one of:
24396 where @code{name} is a string which is matched against the category
24397 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
24398 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
24399 be a substring of the full category name, in order to match multiple
24400 similar categories), the optional "+" prefix tells libvirt to log stack
24401 trace for each message matching name, and @code{x} is the minimal level
24402 where matching messages should be logged:
24419 Multiple filters can be defined in a single filters statement, they just
24420 need to be separated by spaces.
24422 Defaults to @samp{"3:remote 4:event"}.
24426 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
24429 An output is one of the places to save logging information The format
24430 for an output can be:
24434 output goes to stderr
24436 @item x:syslog:name
24437 use syslog for the output and use the given name as the ident
24439 @item x:file:file_path
24440 output to a file, with the given filepath
24443 output to journald logging system
24447 In all case the x prefix is the minimal level, acting as a filter
24464 Multiple outputs can be defined, they just need to be separated by
24467 Defaults to @samp{"3:stderr"}.
24471 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
24472 Maximum number of concurrent client connections to allow over all
24475 Defaults to @samp{1024}.
24479 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
24480 Maximum file size before rolling over.
24482 Defaults to @samp{2MB}
24486 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
24487 Maximum number of backup files to keep.
24489 Defaults to @samp{3}
24493 @subsubheading Transparent Emulation with QEMU
24496 @cindex @code{binfmt_misc}
24497 @code{qemu-binfmt-service-type} provides support for transparent
24498 emulation of program binaries built for different architectures---e.g.,
24499 it allows you to transparently execute an ARMv7 program on an x86_64
24500 machine. It achieves this by combining the @uref{https://www.qemu.org,
24501 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
24503 @defvr {Scheme Variable} qemu-binfmt-service-type
24504 This is the type of the QEMU/binfmt service for transparent emulation.
24505 Its value must be a @code{qemu-binfmt-configuration} object, which
24506 specifies the QEMU package to use as well as the architecture we want to
24510 (service qemu-binfmt-service-type
24511 (qemu-binfmt-configuration
24512 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
24515 In this example, we enable transparent emulation for the ARM and aarch64
24516 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
24517 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
24518 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
24521 @deftp {Data Type} qemu-binfmt-configuration
24522 This is the configuration for the @code{qemu-binfmt} service.
24525 @item @code{platforms} (default: @code{'()})
24526 The list of emulated QEMU platforms. Each item must be a @dfn{platform
24527 object} as returned by @code{lookup-qemu-platforms} (see below).
24529 @item @code{guix-support?} (default: @code{#f})
24530 When it is true, QEMU and all its dependencies are added to the build
24531 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
24532 @option{--chroot-directory} option}). This allows the @code{binfmt_misc}
24533 handlers to be used within the build environment, which in turn means
24534 that you can transparently build programs for another architecture.
24536 For example, let's suppose you're on an x86_64 machine and you have this
24540 (service qemu-binfmt-service-type
24541 (qemu-binfmt-configuration
24542 (platforms (lookup-qemu-platforms "arm"))
24543 (guix-support? #t)))
24549 guix build -s armhf-linux inkscape
24553 and it will build Inkscape for ARMv7 @emph{as if it were a native
24554 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
24555 if you'd like to test a package build for an architecture you don't have
24558 @item @code{qemu} (default: @code{qemu})
24559 The QEMU package to use.
24563 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
24564 Return the list of QEMU platform objects corresponding to
24565 @var{platforms}@dots{}. @var{platforms} must be a list of strings
24566 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
24567 @code{"mips64el"}, and so on.
24570 @deffn {Scheme Procedure} qemu-platform? @var{obj}
24571 Return true if @var{obj} is a platform object.
24574 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
24575 Return the name of @var{platform}---a string such as @code{"arm"}.
24578 @node Version Control Services
24579 @subsection Version Control Services
24581 The @code{(gnu services version-control)} module provides a service to
24582 allow remote access to local Git repositories. There are three options:
24583 the @code{git-daemon-service}, which provides access to repositories via
24584 the @code{git://} unsecured TCP-based protocol, extending the
24585 @code{nginx} web server to proxy some requests to
24586 @code{git-http-backend}, or providing a web interface with
24587 @code{cgit-service-type}.
24589 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
24591 Return a service that runs @command{git daemon}, a simple TCP server to
24592 expose repositories over the Git protocol for anonymous access.
24594 The optional @var{config} argument should be a
24595 @code{<git-daemon-configuration>} object, by default it allows read-only
24596 access to exported@footnote{By creating the magic file
24597 @file{git-daemon-export-ok} in the repository directory.} repositories under
24602 @deftp {Data Type} git-daemon-configuration
24603 Data type representing the configuration for @code{git-daemon-service}.
24606 @item @code{package} (default: @var{git})
24607 Package object of the Git distributed version control system.
24609 @item @code{export-all?} (default: @var{#f})
24610 Whether to allow access for all Git repositories, even if they do not
24611 have the @file{git-daemon-export-ok} file.
24613 @item @code{base-path} (default: @file{/srv/git})
24614 Whether to remap all the path requests as relative to the given path.
24615 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
24616 then if you later try to pull @code{git://example.com/hello.git}, git
24617 daemon will interpret the path as @code{/srv/git/hello.git}.
24619 @item @code{user-path} (default: @var{#f})
24620 Whether to allow @code{~user} notation to be used in requests. When
24621 specified with empty string, requests to @code{git://host/~alice/foo} is
24622 taken as a request to access @code{foo} repository in the home directory
24623 of user @code{alice}. If @var{(user-path "path")} is specified, the
24624 same request is taken as a request to access @code{path/foo} repository
24625 in the home directory of user @code{alice}.
24627 @item @code{listen} (default: @var{'()})
24628 Whether to listen on specific IP addresses or hostnames, defaults to
24631 @item @code{port} (default: @var{#f})
24632 Whether to listen on an alternative port, which defaults to 9418.
24634 @item @code{whitelist} (default: @var{'()})
24635 If not empty, only allow access to this list of directories.
24637 @item @code{extra-options} (default: @var{'()})
24638 Extra options will be passed to @code{git daemon}, please run
24639 @command{man git-daemon} for more information.
24644 The @code{git://} protocol lacks authentication. When you pull from a
24645 repository fetched via @code{git://}, you don't know whether the data you
24646 receive was modified or is even coming from the specified host, and your
24647 connection is subject to eavesdropping. It's better to use an authenticated
24648 and encrypted transport, such as @code{https}. Although Git allows you
24649 to serve repositories using unsophisticated file-based web servers,
24650 there is a faster protocol implemented by the @code{git-http-backend}
24651 program. This program is the back-end of a proper Git web service. It
24652 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
24653 on running the necessary @code{fcgiwrap} daemon.
24655 Guix has a separate configuration data type for serving Git repositories
24658 @deftp {Data Type} git-http-configuration
24659 Data type representing the configuration for a future
24660 @code{git-http-service-type}; can currently be used to configure Nginx
24661 trough @code{git-http-nginx-location-configuration}.
24664 @item @code{package} (default: @var{git})
24665 Package object of the Git distributed version control system.
24667 @item @code{git-root} (default: @file{/srv/git})
24668 Directory containing the Git repositories to expose to the world.
24670 @item @code{export-all?} (default: @var{#f})
24671 Whether to expose access for all Git repositories in @var{git-root},
24672 even if they do not have the @file{git-daemon-export-ok} file.
24674 @item @code{uri-path} (default: @file{/git/})
24675 Path prefix for Git access. With the default @code{/git/} prefix, this
24676 will map @code{http://@var{server}/git/@var{repo}.git} to
24677 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
24678 with this prefix are not passed on to this Git instance.
24680 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
24681 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
24686 There is no @code{git-http-service-type}, currently; instead you can
24687 create an @code{nginx-location-configuration} from a
24688 @code{git-http-configuration} and then add that location to a web
24691 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
24692 [config=(git-http-configuration)]
24693 Compute an @code{nginx-location-configuration} that corresponds to the
24694 given Git http configuration. An example nginx service definition to
24695 serve the default @file{/srv/git} over HTTPS might be:
24698 (service nginx-service-type
24699 (nginx-configuration
24702 (nginx-server-configuration
24703 (listen '("443 ssl"))
24704 (server-name "git.my-host.org")
24706 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
24707 (ssl-certificate-key
24708 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
24711 (git-http-nginx-location-configuration
24712 (git-http-configuration (uri-path "/"))))))))))
24715 This example assumes that you are using Let's Encrypt to get your TLS
24716 certificate. @xref{Certificate Services}. The default @code{certbot}
24717 service will redirect all HTTP traffic on @code{git.my-host.org} to
24718 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
24719 system services. @xref{Web Services}.
24722 @subsubheading Cgit Service
24724 @cindex Cgit service
24725 @cindex Git, web interface
24726 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
24727 repositories written in C.
24729 The following example will configure the service with default values.
24730 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
24733 (service cgit-service-type)
24736 The @code{file-object} type designates either a file-like object
24737 (@pxref{G-Expressions, file-like objects}) or a string.
24739 @c %start of fragment
24741 Available @code{cgit-configuration} fields are:
24743 @deftypevr {@code{cgit-configuration} parameter} package package
24748 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
24749 NGINX configuration.
24753 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
24754 Specifies a command which will be invoked to format the content of about
24755 pages (both top-level and for each repository).
24757 Defaults to @samp{""}.
24761 @deftypevr {@code{cgit-configuration} parameter} string agefile
24762 Specifies a path, relative to each repository path, which can be used to
24763 specify the date and time of the youngest commit in the repository.
24765 Defaults to @samp{""}.
24769 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
24770 Specifies a command that will be invoked for authenticating repository
24773 Defaults to @samp{""}.
24777 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
24778 Flag which, when set to @samp{age}, enables date ordering in the branch
24779 ref list, and when set @samp{name} enables ordering by branch name.
24781 Defaults to @samp{"name"}.
24785 @deftypevr {@code{cgit-configuration} parameter} string cache-root
24786 Path used to store the cgit cache entries.
24788 Defaults to @samp{"/var/cache/cgit"}.
24792 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
24793 Number which specifies the time-to-live, in minutes, for the cached
24794 version of repository pages accessed with a fixed SHA1.
24796 Defaults to @samp{-1}.
24800 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
24801 Number which specifies the time-to-live, in minutes, for the cached
24802 version of repository pages accessed without a fixed SHA1.
24804 Defaults to @samp{5}.
24808 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
24809 Number which specifies the time-to-live, in minutes, for the cached
24810 version of the repository summary page.
24812 Defaults to @samp{5}.
24816 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
24817 Number which specifies the time-to-live, in minutes, for the cached
24818 version of the repository index page.
24820 Defaults to @samp{5}.
24824 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
24825 Number which specifies the time-to-live, in minutes, for the result of
24826 scanning a path for Git repositories.
24828 Defaults to @samp{15}.
24832 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
24833 Number which specifies the time-to-live, in minutes, for the cached
24834 version of the repository about page.
24836 Defaults to @samp{15}.
24840 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
24841 Number which specifies the time-to-live, in minutes, for the cached
24842 version of snapshots.
24844 Defaults to @samp{5}.
24848 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
24849 The maximum number of entries in the cgit cache. When set to @samp{0},
24850 caching is disabled.
24852 Defaults to @samp{0}.
24856 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
24857 Sort items in the repo list case sensitively.
24859 Defaults to @samp{#t}.
24863 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
24864 List of common prefixes which, when combined with a repository URL,
24865 generates valid clone URLs for the repository.
24867 Defaults to @samp{()}.
24871 @deftypevr {@code{cgit-configuration} parameter} list clone-url
24872 List of @code{clone-url} templates.
24874 Defaults to @samp{()}.
24878 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
24879 Command which will be invoked to format commit messages.
24881 Defaults to @samp{""}.
24885 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
24886 Flag which, when set to @samp{date}, enables strict date ordering in the
24887 commit log, and when set to @samp{topo} enables strict topological
24890 Defaults to @samp{"git log"}.
24894 @deftypevr {@code{cgit-configuration} parameter} file-object css
24895 URL which specifies the css document to include in all cgit pages.
24897 Defaults to @samp{"/share/cgit/cgit.css"}.
24901 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
24902 Specifies a command which will be invoked to format names and email
24903 address of committers, authors, and taggers, as represented in various
24904 places throughout the cgit interface.
24906 Defaults to @samp{""}.
24910 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
24911 Flag which, when set to @samp{#t}, will make cgit generate a HTML
24912 fragment suitable for embedding in other HTML pages.
24914 Defaults to @samp{#f}.
24918 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
24919 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
24920 commit history graph to the left of the commit messages in the
24921 repository log page.
24923 Defaults to @samp{#f}.
24927 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
24928 Flag which, when set to @samp{#t}, allows all filter settings to be
24929 overridden in repository-specific cgitrc files.
24931 Defaults to @samp{#f}.
24935 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
24936 Flag which, when set to @samp{#t}, allows users to follow a file in the
24939 Defaults to @samp{#f}.
24943 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
24944 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
24947 Defaults to @samp{#t}.
24951 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
24952 Flag which, when set to @samp{#t}, will make cgit generate extra links
24953 "summary", "commit", "tree" for each repo in the repository index.
24955 Defaults to @samp{#f}.
24959 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
24960 Flag which, when set to @samp{#t}, will make cgit display the owner of
24961 each repo in the repository index.
24963 Defaults to @samp{#t}.
24967 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
24968 Flag which, when set to @samp{#t}, will make cgit print the number of
24969 modified files for each commit on the repository log page.
24971 Defaults to @samp{#f}.
24975 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
24976 Flag which, when set to @samp{#t}, will make cgit print the number of
24977 added and removed lines for each commit on the repository log page.
24979 Defaults to @samp{#f}.
24983 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
24984 Flag which, when set to @code{#t}, will make cgit display remote
24985 branches in the summary and refs views.
24987 Defaults to @samp{#f}.
24991 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
24992 Flag which, when set to @code{1}, will make cgit use the subject of the
24993 parent commit as link text when generating links to parent commits in
24996 Defaults to @samp{#f}.
25000 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
25001 Flag which, when set to @samp{#t}, will make cgit use the subject of the
25002 parent commit as link text when generating links to parent commits in
25005 Defaults to @samp{#f}.
25009 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
25010 Flag which, when set to @samp{#t}, will make cgit generate linenumber
25011 links for plaintext blobs printed in the tree view.
25013 Defaults to @samp{#t}.
25017 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
25018 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
25019 set any repo specific settings.
25021 Defaults to @samp{#f}.
25025 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
25026 URL used as link to a shortcut icon for cgit.
25028 Defaults to @samp{"/favicon.ico"}.
25032 @deftypevr {@code{cgit-configuration} parameter} string footer
25033 The content of the file specified with this option will be included
25034 verbatim at the bottom of all pages (i.e.@: it replaces the standard
25035 "generated by..."@: message).
25037 Defaults to @samp{""}.
25041 @deftypevr {@code{cgit-configuration} parameter} string head-include
25042 The content of the file specified with this option will be included
25043 verbatim in the HTML HEAD section on all pages.
25045 Defaults to @samp{""}.
25049 @deftypevr {@code{cgit-configuration} parameter} string header
25050 The content of the file specified with this option will be included
25051 verbatim at the top of all pages.
25053 Defaults to @samp{""}.
25057 @deftypevr {@code{cgit-configuration} parameter} file-object include
25058 Name of a configfile to include before the rest of the current config-
25061 Defaults to @samp{""}.
25065 @deftypevr {@code{cgit-configuration} parameter} string index-header
25066 The content of the file specified with this option will be included
25067 verbatim above the repository index.
25069 Defaults to @samp{""}.
25073 @deftypevr {@code{cgit-configuration} parameter} string index-info
25074 The content of the file specified with this option will be included
25075 verbatim below the heading on the repository index page.
25077 Defaults to @samp{""}.
25081 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
25082 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
25083 in the servers timezone.
25085 Defaults to @samp{#f}.
25089 @deftypevr {@code{cgit-configuration} parameter} file-object logo
25090 URL which specifies the source of an image which will be used as a logo
25093 Defaults to @samp{"/share/cgit/cgit.png"}.
25097 @deftypevr {@code{cgit-configuration} parameter} string logo-link
25098 URL loaded when clicking on the cgit logo image.
25100 Defaults to @samp{""}.
25104 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
25105 Command which will be invoked to format the Owner column of the main
25108 Defaults to @samp{""}.
25112 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
25113 Number of items to display in atom feeds view.
25115 Defaults to @samp{10}.
25119 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
25120 Number of entries to list per page in "log" view.
25122 Defaults to @samp{50}.
25126 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
25127 Number of commit message characters to display in "log" view.
25129 Defaults to @samp{80}.
25133 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
25134 Specifies the number of entries to list per page on the repository index
25137 Defaults to @samp{50}.
25141 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
25142 Specifies the maximum number of repo description characters to display
25143 on the repository index page.
25145 Defaults to @samp{80}.
25149 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
25150 Specifies the maximum size of a blob to display HTML for in KBytes.
25152 Defaults to @samp{0}.
25156 @deftypevr {@code{cgit-configuration} parameter} string max-stats
25157 Maximum statistics period. Valid values are @samp{week},@samp{month},
25158 @samp{quarter} and @samp{year}.
25160 Defaults to @samp{""}.
25164 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
25165 Mimetype for the specified filename extension.
25167 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
25168 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
25169 "image/png") (svg "image/svg+xml"))}.
25173 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
25174 Specifies the file to use for automatic mimetype lookup.
25176 Defaults to @samp{""}.
25180 @deftypevr {@code{cgit-configuration} parameter} string module-link
25181 Text which will be used as the formatstring for a hyperlink when a
25182 submodule is printed in a directory listing.
25184 Defaults to @samp{""}.
25188 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
25189 If set to the value @samp{#t} caching will be disabled.
25191 Defaults to @samp{#f}.
25195 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
25196 If set to @samp{#t} showing full author email addresses will be
25199 Defaults to @samp{#f}.
25203 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
25204 Flag which, when set to @samp{#t}, will make cgit omit the standard
25205 header on all pages.
25207 Defaults to @samp{#f}.
25211 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
25212 A list of subdirectories inside of @code{repository-directory}, relative
25213 to it, that should loaded as Git repositories. An empty list means that
25214 all subdirectories will be loaded.
25216 Defaults to @samp{()}.
25220 @deftypevr {@code{cgit-configuration} parameter} file-object readme
25221 Text which will be used as default value for @code{cgit-repo-readme}.
25223 Defaults to @samp{""}.
25227 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
25228 If set to @code{#t} and @code{repository-directory} is enabled, if any
25229 repositories are found with a suffix of @code{.git}, this suffix will be
25230 removed for the URL and name.
25232 Defaults to @samp{#f}.
25236 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
25237 Maximum number of files to consider when detecting renames.
25239 Defaults to @samp{-1}.
25243 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
25244 The way in which repositories in each section are sorted.
25246 Defaults to @samp{""}.
25250 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
25251 Text used as content for the @code{robots} meta-tag.
25253 Defaults to @samp{("noindex" "nofollow")}.
25257 @deftypevr {@code{cgit-configuration} parameter} string root-desc
25258 Text printed below the heading on the repository index page.
25260 Defaults to @samp{"a fast webinterface for the git dscm"}.
25264 @deftypevr {@code{cgit-configuration} parameter} string root-readme
25265 The content of the file specified with this option will be included
25266 verbatim below the ``about'' link on the repository index page.
25268 Defaults to @samp{""}.
25272 @deftypevr {@code{cgit-configuration} parameter} string root-title
25273 Text printed as heading on the repository index page.
25275 Defaults to @samp{""}.
25279 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
25280 If set to @samp{#t} and repository-directory is enabled,
25281 repository-directory will recurse into directories whose name starts
25282 with a period. Otherwise, repository-directory will stay away from such
25283 directories, considered as ``hidden''. Note that this does not apply to
25284 the @file{.git} directory in non-bare repos.
25286 Defaults to @samp{#f}.
25290 @deftypevr {@code{cgit-configuration} parameter} list snapshots
25291 Text which specifies the default set of snapshot formats that cgit
25292 generates links for.
25294 Defaults to @samp{()}.
25298 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
25299 Name of the directory to scan for repositories (represents
25302 Defaults to @samp{"/srv/git"}.
25306 @deftypevr {@code{cgit-configuration} parameter} string section
25307 The name of the current repository section - all repositories defined
25308 after this option will inherit the current section name.
25310 Defaults to @samp{""}.
25314 @deftypevr {@code{cgit-configuration} parameter} string section-sort
25315 Flag which, when set to @samp{1}, will sort the sections on the
25316 repository listing by name.
25318 Defaults to @samp{""}.
25322 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
25323 A number which, if defined prior to repository-directory, specifies how
25324 many path elements from each repo path to use as a default section name.
25326 Defaults to @samp{0}.
25330 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
25331 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
25334 Defaults to @samp{#f}.
25338 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
25339 Specifies a command which will be invoked to format plaintext blobs in
25342 Defaults to @samp{""}.
25346 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
25347 Specifies the number of branches to display in the repository ``summary''
25350 Defaults to @samp{10}.
25354 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
25355 Specifies the number of log entries to display in the repository
25358 Defaults to @samp{10}.
25362 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
25363 Specifies the number of tags to display in the repository ``summary''
25366 Defaults to @samp{10}.
25370 @deftypevr {@code{cgit-configuration} parameter} string strict-export
25371 Filename which, if specified, needs to be present within the repository
25372 for cgit to allow access to that repository.
25374 Defaults to @samp{""}.
25378 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
25379 URL which, if specified, will be used as root for all cgit links.
25381 Defaults to @samp{"/"}.
25385 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
25386 A list of @dfn{cgit-repo} records to use with config.
25388 Defaults to @samp{()}.
25390 Available @code{repository-cgit-configuration} fields are:
25392 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
25393 A mask of snapshot formats for this repo that cgit generates links for,
25394 restricted by the global @code{snapshots} setting.
25396 Defaults to @samp{()}.
25400 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
25401 Override the default @code{source-filter}.
25403 Defaults to @samp{""}.
25407 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
25408 The relative URL used to access the repository.
25410 Defaults to @samp{""}.
25414 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
25415 Override the default @code{about-filter}.
25417 Defaults to @samp{""}.
25421 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
25422 Flag which, when set to @samp{age}, enables date ordering in the branch
25423 ref list, and when set to @samp{name} enables ordering by branch name.
25425 Defaults to @samp{""}.
25429 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
25430 A list of URLs which can be used to clone repo.
25432 Defaults to @samp{()}.
25436 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
25437 Override the default @code{commit-filter}.
25439 Defaults to @samp{""}.
25443 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
25444 Flag which, when set to @samp{date}, enables strict date ordering in the
25445 commit log, and when set to @samp{topo} enables strict topological
25448 Defaults to @samp{""}.
25452 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
25453 The name of the default branch for this repository. If no such branch
25454 exists in the repository, the first branch name (when sorted) is used as
25455 default instead. By default branch pointed to by HEAD, or ``master'' if
25456 there is no suitable HEAD.
25458 Defaults to @samp{""}.
25462 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
25463 The value to show as repository description.
25465 Defaults to @samp{""}.
25469 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
25470 The value to show as repository homepage.
25472 Defaults to @samp{""}.
25476 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
25477 Override the default @code{email-filter}.
25479 Defaults to @samp{""}.
25483 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
25484 A flag which can be used to disable the global setting
25485 @code{enable-commit-graph?}.
25487 Defaults to @samp{disabled}.
25491 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
25492 A flag which can be used to disable the global setting
25493 @code{enable-log-filecount?}.
25495 Defaults to @samp{disabled}.
25499 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
25500 A flag which can be used to disable the global setting
25501 @code{enable-log-linecount?}.
25503 Defaults to @samp{disabled}.
25507 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
25508 Flag which, when set to @code{#t}, will make cgit display remote
25509 branches in the summary and refs views.
25511 Defaults to @samp{disabled}.
25515 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
25516 A flag which can be used to override the global setting
25517 @code{enable-subject-links?}.
25519 Defaults to @samp{disabled}.
25523 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
25524 A flag which can be used to override the global setting
25525 @code{enable-html-serving?}.
25527 Defaults to @samp{disabled}.
25531 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
25532 Flag which, when set to @code{#t}, hides the repository from the
25535 Defaults to @samp{#f}.
25539 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
25540 Flag which, when set to @samp{#t}, ignores the repository.
25542 Defaults to @samp{#f}.
25546 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
25547 URL which specifies the source of an image which will be used as a logo
25548 on this repo’s pages.
25550 Defaults to @samp{""}.
25554 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
25555 URL loaded when clicking on the cgit logo image.
25557 Defaults to @samp{""}.
25561 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
25562 Override the default @code{owner-filter}.
25564 Defaults to @samp{""}.
25568 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
25569 Text which will be used as the formatstring for a hyperlink when a
25570 submodule is printed in a directory listing. The arguments for the
25571 formatstring are the path and SHA1 of the submodule commit.
25573 Defaults to @samp{""}.
25577 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
25578 Text which will be used as the formatstring for a hyperlink when a
25579 submodule with the specified subdirectory path is printed in a directory
25582 Defaults to @samp{()}.
25586 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
25587 Override the default maximum statistics period.
25589 Defaults to @samp{""}.
25593 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
25594 The value to show as repository name.
25596 Defaults to @samp{""}.
25600 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
25601 A value used to identify the owner of the repository.
25603 Defaults to @samp{""}.
25607 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
25608 An absolute path to the repository directory.
25610 Defaults to @samp{""}.
25614 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
25615 A path (relative to repo) which specifies a file to include verbatim as
25616 the ``About'' page for this repo.
25618 Defaults to @samp{""}.
25622 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
25623 The name of the current repository section - all repositories defined
25624 after this option will inherit the current section name.
25626 Defaults to @samp{""}.
25630 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
25631 Extra options will be appended to cgitrc file.
25633 Defaults to @samp{()}.
25639 @deftypevr {@code{cgit-configuration} parameter} list extra-options
25640 Extra options will be appended to cgitrc file.
25642 Defaults to @samp{()}.
25647 @c %end of fragment
25649 However, it could be that you just want to get a @code{cgitrc} up and
25650 running. In that case, you can pass an @code{opaque-cgit-configuration}
25651 as a record to @code{cgit-service-type}. As its name indicates, an
25652 opaque configuration does not have easy reflective capabilities.
25654 Available @code{opaque-cgit-configuration} fields are:
25656 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
25660 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
25661 The contents of the @code{cgitrc}, as a string.
25664 For example, if your @code{cgitrc} is just the empty string, you
25665 could instantiate a cgit service like this:
25668 (service cgit-service-type
25669 (opaque-cgit-configuration
25673 @subsubheading Gitolite Service
25675 @cindex Gitolite service
25676 @cindex Git, hosting
25677 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
25678 repositories on a central server.
25680 Gitolite can handle multiple repositories and users, and supports flexible
25681 configuration of the permissions for the users on the repositories.
25683 The following example will configure Gitolite using the default @code{git}
25684 user, and the provided SSH public key.
25687 (service gitolite-service-type
25688 (gitolite-configuration
25689 (admin-pubkey (plain-file
25691 "ssh-rsa AAAA... guix@@example.com"))))
25694 Gitolite is configured through a special admin repository which you can clone,
25695 for example, if you setup Gitolite on @code{example.com}, you would run the
25696 following command to clone the admin repository.
25699 git clone git@@example.com:gitolite-admin
25702 When the Gitolite service is activated, the provided @code{admin-pubkey} will
25703 be inserted in to the @file{keydir} directory in the gitolite-admin
25704 repository. If this results in a change in the repository, it will be
25705 committed using the message ``gitolite setup by GNU Guix''.
25707 @deftp {Data Type} gitolite-configuration
25708 Data type representing the configuration for @code{gitolite-service-type}.
25711 @item @code{package} (default: @var{gitolite})
25712 Gitolite package to use.
25714 @item @code{user} (default: @var{git})
25715 User to use for Gitolite. This will be user that you use when accessing
25718 @item @code{group} (default: @var{git})
25719 Group to use for Gitolite.
25721 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
25722 Directory in which to store the Gitolite configuration and repositories.
25724 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
25725 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
25726 representing the configuration for Gitolite.
25728 @item @code{admin-pubkey} (default: @var{#f})
25729 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
25730 setup Gitolite. This will be inserted in to the @file{keydir} directory
25731 within the gitolite-admin repository.
25733 To specify the SSH key as a string, use the @code{plain-file} function.
25736 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
25742 @deftp {Data Type} gitolite-rc-file
25743 Data type representing the Gitolite RC file.
25746 @item @code{umask} (default: @code{#o0077})
25747 This controls the permissions Gitolite sets on the repositories and their
25750 A value like @code{#o0027} will give read access to the group used by Gitolite
25751 (by default: @code{git}). This is necessary when using Gitolite with software
25752 like cgit or gitweb.
25754 @item @code{git-config-keys} (default: @code{""})
25755 Gitolite allows you to set git config values using the @samp{config} keyword. This
25756 setting allows control over the config keys to accept.
25758 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
25759 Set the role names allowed to be used by users running the perms command.
25761 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
25762 This setting controls the commands and features to enable within Gitolite.
25768 @node Game Services
25769 @subsection Game Services
25771 @subsubheading The Battle for Wesnoth Service
25773 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
25774 based tactical strategy game, with several single player campaigns, and
25775 multiplayer games (both networked and local).
25777 @defvar {Scheme Variable} wesnothd-service-type
25778 Service type for the wesnothd service. Its value must be a
25779 @code{wesnothd-configuration} object. To run wesnothd in the default
25780 configuration, instantiate it as:
25783 (service wesnothd-service-type)
25787 @deftp {Data Type} wesnothd-configuration
25788 Data type representing the configuration of @command{wesnothd}.
25791 @item @code{package} (default: @code{wesnoth-server})
25792 The wesnoth server package to use.
25794 @item @code{port} (default: @code{15000})
25795 The port to bind the server to.
25800 @node PAM Mount Service
25801 @subsection PAM Mount Service
25804 The @code{(gnu services pam-mount)} module provides a service allowing
25805 users to mount volumes when they log in. It should be able to mount any
25806 volume format supported by the system.
25808 @defvar {Scheme Variable} pam-mount-service-type
25809 Service type for PAM Mount support.
25812 @deftp {Data Type} pam-mount-configuration
25813 Data type representing the configuration of PAM Mount.
25815 It takes the following parameters:
25819 The configuration rules that will be used to generate
25820 @file{/etc/security/pam_mount.conf.xml}.
25822 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
25823 Guile Reference Manual}), and the the default ones don't mount anything
25824 for anyone at login:
25827 `((debug (@@ (enable "0")))
25828 (mntoptions (@@ (allow ,(string-join
25829 '("nosuid" "nodev" "loop"
25830 "encryption" "fsck" "nonempty"
25831 "allow_root" "allow_other")
25833 (mntoptions (@@ (require "nosuid,nodev")))
25834 (logout (@@ (wait "0")
25838 (mkmountpoint (@@ (enable "1")
25842 Some @code{volume} elements must be added to automatically mount volumes
25843 at login. Here's an example allowing the user @code{alice} to mount her
25844 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
25845 the partition where he stores his data:
25848 (define pam-mount-rules
25849 `((debug (@@ (enable "0")))
25850 (volume (@@ (user "alice")
25853 (mountpoint "/home/alice")))
25854 (volume (@@ (user "bob")
25857 (mountpoint "/home/bob/data")
25858 (options "defaults,autodefrag,compress")))
25859 (mntoptions (@@ (allow ,(string-join
25860 '("nosuid" "nodev" "loop"
25861 "encryption" "fsck" "nonempty"
25862 "allow_root" "allow_other")
25864 (mntoptions (@@ (require "nosuid,nodev")))
25865 (logout (@@ (wait "0")
25869 (mkmountpoint (@@ (enable "1")
25870 (remove "true")))))
25872 (service pam-mount-service-type
25873 (pam-mount-configuration
25874 (rules pam-mount-rules)))
25877 The complete list of possible options can be found in the man page for
25878 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
25883 @node Guix Services
25884 @subsection Guix Services
25886 @subsubheading Guix Data Service
25887 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
25888 and provides data about GNU Guix. This includes information about
25889 packages, derivations and lint warnings.
25891 The data is stored in a PostgreSQL database, and available through a web
25894 @defvar {Scheme Variable} guix-data-service-type
25895 Service type for the Guix Data Service. Its value must be a
25896 @code{guix-data-service-configuration} object. The service optionally
25897 extends the getmail service, as the guix-commits mailing list is used to
25898 find out about changes in the Guix git repository.
25901 @deftp {Data Type} guix-data-service-configuration
25902 Data type representing the configuration of the Guix Data Service.
25905 @item @code{package} (default: @code{guix-data-service})
25906 The Guix Data Service package to use.
25908 @item @code{user} (default: @code{"guix-data-service"})
25909 The system user to run the service as.
25911 @item @code{group} (default: @code{"guix-data-service"})
25912 The system group to run the service as.
25914 @item @code{port} (default: @code{8765})
25915 The port to bind the web service to.
25917 @item @code{host} (default: @code{"127.0.0.1"})
25918 The host to bind the web service to.
25920 @item @code{getmail-idle-mailboxes} (default: @code{#f})
25921 If set, this is the list of mailboxes that the getmail service will be
25922 configured to listen to.
25924 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
25925 If set, this is the @code{getmail-retriever-configuration} object with
25926 which to configure getmail to fetch mail from the guix-commits mailing
25929 @item @code{extra-options} (default: @var{'()})
25930 Extra command line options for @code{guix-data-service}.
25932 @item @code{extra-process-jobs-options} (default: @var{'()})
25933 Extra command line options for @code{guix-data-service-process-jobs}.
25938 @node Linux Services
25939 @subsection Linux Services
25942 @cindex out of memory killer
25944 @cindex early out of memory daemon
25945 @subsubheading Early OOM Service
25947 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
25948 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
25949 space and provides a more responsive and configurable alternative to the
25950 in-kernel OOM killer. It is useful to prevent the system from becoming
25951 unresponsive when it runs out of memory.
25953 @deffn {Scheme Variable} earlyoom-service-type
25954 The service type for running @command{earlyoom}, the Early OOM daemon.
25955 Its value must be a @code{earlyoom-configuration} object, described
25956 below. The service can be instantiated in its default configuration
25960 (service earlyoom-service-type)
25964 @deftp {Data Type} earlyoom-configuration
25965 This is the configuration record for the @code{earlyoom-service-type}.
25968 @item @code{earlyoom} (default: @var{earlyoom})
25969 The Earlyoom package to use.
25971 @item @code{minimum-available-memory} (default: @code{10})
25972 The threshold for the minimum @emph{available} memory, in percentages.
25974 @item @code{minimum-free-swap} (default: @code{10})
25975 The threshold for the minimum free swap memory, in percentages.
25977 @item @code{prefer-regexp} (default: @code{#f})
25978 A regular expression (as a string) to match the names of the processes
25979 that should be preferably killed.
25981 @item @code{avoid-regexp} (default: @code{#f})
25982 A regular expression (as a string) to match the names of the processes
25983 that should @emph{not} be killed.
25985 @item @code{memory-report-interval} (default: @code{0})
25986 The interval in seconds at which a memory report is printed. It is
25987 disabled by default.
25989 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
25990 A boolean indicating whether the positive adjustments set in
25991 @file{/proc/*/oom_score_adj}.
25993 @item @code{show-debug-messages?} (default: @code{#f})
25994 A boolean indicating whether debug messages should be printed. The logs
25995 are saved at @file{/var/log/earlyoom.log}.
25997 @item @code{send-notification-command} (default: @code{#f})
25998 This can be used to provide a custom command used for sending
26004 @cindex kernel module loader
26005 @subsubheading Kernel Module Loader Service
26007 The kernel module loader service allows one to load loadable kernel
26008 modules at boot. This is especially useful for modules that don't
26009 autoload and need to be manually loaded, as it's the case with
26012 @deffn {Scheme Variable} kernel-module-loader-service-type
26013 The service type for loading loadable kernel modules at boot with
26014 @command{modprobe}. Its value must be a list of strings representing
26015 module names. For example loading the drivers provided by
26016 @code{ddcci-driver-linux}, in debugging mode by passing some module
26017 parameters, can be done as follow:
26020 (use-modules (gnu) (gnu services))
26021 (use-package-modules linux)
26022 (use-service-modules linux)
26024 (define ddcci-config
26025 (plain-file "ddcci.conf"
26026 "options ddcci dyndbg delay=120"))
26030 (services (cons* (service kernel-module-loader-service-type
26031 '("ddcci" "ddcci_backlight"))
26032 (simple-service 'ddcci-config etc-service-type
26033 (list `("modprobe.d/ddcci.conf"
26036 (kernel-loadable-modules (list ddcci-driver-linux)))
26040 @node Miscellaneous Services
26041 @subsection Miscellaneous Services
26043 @cindex fingerprint
26044 @subsubheading Fingerprint Service
26046 The @code{(gnu services authentication)} module provides a DBus service to
26047 read and identify fingerprints via a fingerprint sensor.
26049 @defvr {Scheme Variable} fprintd-service-type
26050 The service type for @command{fprintd}, which provides the fingerprint
26051 reading capability.
26054 (service fprintd-service-type)
26059 @subsubheading System Control Service
26061 The @code{(gnu services sysctl)} provides a service to configure kernel
26062 parameters at boot.
26064 @defvr {Scheme Variable} sysctl-service-type
26065 The service type for @command{sysctl}, which modifies kernel parameters
26066 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
26070 (service sysctl-service-type
26071 (sysctl-configuration
26072 (settings '(("net.ipv4.ip_forward" . "1")))))
26076 @deftp {Data Type} sysctl-configuration
26077 The data type representing the configuration of @command{sysctl}.
26080 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
26081 The @command{sysctl} executable to use.
26083 @item @code{settings} (default: @code{'()})
26084 An association list specifies kernel parameters and their values.
26089 @subsubheading PC/SC Smart Card Daemon Service
26091 The @code{(gnu services security-token)} module provides the following service
26092 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
26093 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
26094 manager that coordinates communications with smart card readers, smart cards
26095 and cryptographic tokens that are connected to the system.
26097 @defvr {Scheme Variable} pcscd-service-type
26098 Service type for the @command{pcscd} service. Its value must be a
26099 @code{pcscd-configuration} object. To run pcscd in the default
26100 configuration, instantiate it as:
26103 (service pcscd-service-type)
26107 @deftp {Data Type} pcscd-configuration
26108 The data type representing the configuration of @command{pcscd}.
26111 @item @code{pcsc-lite} (default: @code{pcsc-lite})
26112 The pcsc-lite package that provides pcscd.
26113 @item @code{usb-drivers} (default: @code{(list ccid)})
26114 List of packages that provide USB drivers to pcscd. Drivers are expected to be
26115 under @file{pcsc/drivers} in the store directory of the package.
26120 @subsubheading Lirc Service
26122 The @code{(gnu services lirc)} module provides the following service.
26124 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
26125 [#:device #f] [#:driver #f] [#:config-file #f] @
26126 [#:extra-options '()]
26127 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
26128 decodes infrared signals from remote controls.
26130 Optionally, @var{device}, @var{driver} and @var{config-file}
26131 (configuration file name) may be specified. See @command{lircd} manual
26134 Finally, @var{extra-options} is a list of additional command-line options
26135 passed to @command{lircd}.
26139 @subsubheading Spice Service
26141 The @code{(gnu services spice)} module provides the following service.
26143 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
26144 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
26145 that enables sharing the clipboard with a vm and setting the guest display
26146 resolution when the graphical console window resizes.
26149 @cindex inputattach
26150 @subsubheading inputattach Service
26152 @cindex tablet input, for Xorg
26153 @cindex touchscreen input, for Xorg
26154 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
26155 use input devices such as Wacom tablets, touchscreens, or joysticks with the
26156 Xorg display server.
26158 @deffn {Scheme Variable} inputattach-service-type
26159 Type of a service that runs @command{inputattach} on a device and
26160 dispatches events from it.
26163 @deftp {Data Type} inputattach-configuration
26165 @item @code{device-type} (default: @code{"wacom"})
26166 The type of device to connect to. Run @command{inputattach --help}, from the
26167 @code{inputattach} package, to see the list of supported device types.
26169 @item @code{device} (default: @code{"/dev/ttyS0"})
26170 The device file to connect to the device.
26172 @item @code{baud-rate} (default: @code{#f})
26173 Baud rate to use for the serial connection.
26174 Should be a number or @code{#f}.
26176 @item @code{log-file} (default: @code{#f})
26177 If true, this must be the name of a file to log messages to.
26181 @subsubheading Dictionary Service
26183 The @code{(gnu services dict)} module provides the following service:
26185 @defvr {Scheme Variable} dicod-service-type
26186 This is the type of the service that runs the @command{dicod} daemon, an
26187 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
26190 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
26191 Return a service that runs the @command{dicod} daemon, an implementation
26192 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
26194 The optional @var{config} argument specifies the configuration for
26195 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
26196 default it serves the GNU Collaborative International Dictionary of English.
26198 You can add @command{open localhost} to your @file{~/.dico} file to make
26199 @code{localhost} the default server for @command{dico} client
26200 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
26203 @deftp {Data Type} dicod-configuration
26204 Data type representing the configuration of dicod.
26207 @item @code{dico} (default: @var{dico})
26208 Package object of the GNU Dico dictionary server.
26210 @item @code{interfaces} (default: @var{'("localhost")})
26211 This is the list of IP addresses and ports and possibly socket file
26212 names to listen to (@pxref{Server Settings, @code{listen} directive,,
26213 dico, GNU Dico Manual}).
26215 @item @code{handlers} (default: @var{'()})
26216 List of @code{<dicod-handler>} objects denoting handlers (module instances).
26218 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
26219 List of @code{<dicod-database>} objects denoting dictionaries to be served.
26223 @deftp {Data Type} dicod-handler
26224 Data type representing a dictionary handler (module instance).
26228 Name of the handler (module instance).
26230 @item @code{module} (default: @var{#f})
26231 Name of the dicod module of the handler (instance). If it is @code{#f},
26232 the module has the same name as the handler.
26233 (@pxref{Modules,,, dico, GNU Dico Manual}).
26235 @item @code{options}
26236 List of strings or gexps representing the arguments for the module handler
26240 @deftp {Data Type} dicod-database
26241 Data type representing a dictionary database.
26245 Name of the database, will be used in DICT commands.
26247 @item @code{handler}
26248 Name of the dicod handler (module instance) used by this database
26249 (@pxref{Handlers,,, dico, GNU Dico Manual}).
26251 @item @code{complex?} (default: @var{#f})
26252 Whether the database configuration complex. The complex configuration
26253 will need a corresponding @code{<dicod-handler>} object, otherwise not.
26255 @item @code{options}
26256 List of strings or gexps representing the arguments for the database
26257 (@pxref{Databases,,, dico, GNU Dico Manual}).
26261 @defvr {Scheme Variable} %dicod-database:gcide
26262 A @code{<dicod-database>} object serving the GNU Collaborative International
26263 Dictionary of English using the @code{gcide} package.
26266 The following is an example @code{dicod-service} configuration.
26269 (dicod-service #:config
26270 (dicod-configuration
26271 (handlers (list (dicod-handler
26275 (list #~(string-append "dbdir=" #$wordnet))))))
26276 (databases (list (dicod-database
26279 (handler "wordnet")
26280 (options '("database=wn")))
26281 %dicod-database:gcide))))
26285 @subsubheading Docker Service
26287 The @code{(gnu services docker)} module provides the following services.
26289 @defvr {Scheme Variable} docker-service-type
26291 This is the type of the service that runs @url{https://www.docker.com,Docker},
26292 a daemon that can execute application bundles (sometimes referred to as
26293 ``containers'') in isolated environments.
26297 @deftp {Data Type} docker-configuration
26298 This is the data type representing the configuration of Docker and Containerd.
26302 @item @code{package} (default: @code{docker})
26303 The Docker package to use.
26305 @item @code{containerd} (default: @var{containerd})
26306 The Containerd package to use.
26308 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
26309 The Docker user-land networking proxy package to use.
26311 @item @code{enable-proxy?} (default @code{#f})
26312 Enable or disable the use of the Docker user-land networking proxy.
26314 @item @code{debug?} (default @code{#f})
26315 Enable or disable debug output.
26321 @subsubheading Auditd Service
26323 The @code{(gnu services auditd)} module provides the following service.
26325 @defvr {Scheme Variable} auditd-service-type
26327 This is the type of the service that runs
26328 @url{https://people.redhat.com/sgrubb/audit/,auditd},
26329 a daemon that tracks security-relevant information on your system.
26331 Examples of things that can be tracked:
26341 Failed login attempts
26348 @command{auditctl} from the @code{audit} package can be used in order
26349 to add or remove events to be tracked (until the next reboot).
26350 In order to permanently track events, put the command line arguments
26351 of auditctl into @file{/etc/audit/audit.rules}.
26352 @command{aureport} from the @code{audit} package can be used in order
26353 to view a report of all recorded events.
26354 The audit daemon usually logs into the directory @file{/var/log/audit}.
26358 @deftp {Data Type} auditd-configuration
26359 This is the data type representing the configuration of auditd.
26363 @item @code{audit} (default: @code{audit})
26364 The audit package to use.
26369 @defvr {Scheme Variable} singularity-service-type
26370 This is the type of the service that allows you to run
26371 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
26372 create and run application bundles (aka. ``containers''). The value for this
26373 service is the Singularity package to use.
26375 The service does not install a daemon; instead, it installs helper programs as
26376 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
26377 @command{singularity run} and similar commands.
26381 @subsubheading Nix service
26383 The @code{(gnu services nix)} module provides the following service.
26385 @defvr {Scheme Variable} nix-service-type
26387 This is the type of the service that runs build daemon of the
26388 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
26392 (use-modules (gnu))
26393 (use-service-modules nix)
26394 (use-package-modules package-management)
26398 (packages (append (list nix)
26401 (services (append (list (service nix-service-type))
26405 After @command{guix system reconfigure} configure Nix for your user:
26408 @item Add a Nix channel and update it. See
26409 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
26411 @item Create a symlink to your profile and activate Nix profile:
26415 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
26416 $ source /run/current-system/profile/etc/profile.d/nix.sh
26421 @node Setuid Programs
26422 @section Setuid Programs
26424 @cindex setuid programs
26425 Some programs need to run with ``root'' privileges, even when they are
26426 launched by unprivileged users. A notorious example is the
26427 @command{passwd} program, which users can run to change their
26428 password, and which needs to access the @file{/etc/passwd} and
26429 @file{/etc/shadow} files---something normally restricted to root, for
26430 obvious security reasons. To address that, these executables are
26431 @dfn{setuid-root}, meaning that they always run with root privileges
26432 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
26433 for more info about the setuid mechanism).
26435 The store itself @emph{cannot} contain setuid programs: that would be a
26436 security issue since any user on the system can write derivations that
26437 populate the store (@pxref{The Store}). Thus, a different mechanism is
26438 used: instead of changing the setuid bit directly on files that are in
26439 the store, we let the system administrator @emph{declare} which programs
26440 should be setuid root.
26442 The @code{setuid-programs} field of an @code{operating-system}
26443 declaration contains a list of G-expressions denoting the names of
26444 programs to be setuid-root (@pxref{Using the Configuration System}).
26445 For instance, the @command{passwd} program, which is part of the Shadow
26446 package, can be designated by this G-expression (@pxref{G-Expressions}):
26449 #~(string-append #$shadow "/bin/passwd")
26452 A default set of setuid programs is defined by the
26453 @code{%setuid-programs} variable of the @code{(gnu system)} module.
26455 @defvr {Scheme Variable} %setuid-programs
26456 A list of G-expressions denoting common programs that are setuid-root.
26458 The list includes commands such as @command{passwd}, @command{ping},
26459 @command{su}, and @command{sudo}.
26462 Under the hood, the actual setuid programs are created in the
26463 @file{/run/setuid-programs} directory at system activation time. The
26464 files in this directory refer to the ``real'' binaries, which are in the
26467 @node X.509 Certificates
26468 @section X.509 Certificates
26470 @cindex HTTPS, certificates
26471 @cindex X.509 certificates
26473 Web servers available over HTTPS (that is, HTTP over the transport-layer
26474 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
26475 that the client can then use to @emph{authenticate} the server. To do
26476 that, clients verify that the server's certificate is signed by a
26477 so-called @dfn{certificate authority} (CA). But to verify the CA's
26478 signature, clients must have first acquired the CA's certificate.
26480 Web browsers such as GNU@tie{}IceCat include their own set of CA
26481 certificates, such that they are able to verify CA signatures
26484 However, most other programs that can talk HTTPS---@command{wget},
26485 @command{git}, @command{w3m}, etc.---need to be told where CA
26486 certificates can be found.
26488 @cindex @code{nss-certs}
26489 In Guix, this is done by adding a package that provides certificates
26490 to the @code{packages} field of the @code{operating-system} declaration
26491 (@pxref{operating-system Reference}). Guix includes one such package,
26492 @code{nss-certs}, which is a set of CA certificates provided as part of
26493 Mozilla's Network Security Services.
26495 Note that it is @emph{not} part of @code{%base-packages}, so you need to
26496 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
26497 most applications and libraries look for certificates by default, points
26498 to the certificates installed globally.
26500 Unprivileged users, including users of Guix on a foreign distro,
26501 can also install their own certificate package in
26502 their profile. A number of environment variables need to be defined so
26503 that applications and libraries know where to find them. Namely, the
26504 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
26505 variables. Some applications add their own environment variables; for
26506 instance, the Git version control system honors the certificate bundle
26507 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
26508 would typically run something like:
26511 guix install nss-certs
26512 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
26513 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
26514 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
26517 As another example, R requires the @env{CURL_CA_BUNDLE} environment
26518 variable to point to a certificate bundle, so you would have to run
26519 something like this:
26522 guix install nss-certs
26523 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
26526 For other applications you may want to look up the required environment
26527 variable in the relevant documentation.
26530 @node Name Service Switch
26531 @section Name Service Switch
26533 @cindex name service switch
26535 The @code{(gnu system nss)} module provides bindings to the
26536 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
26537 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
26538 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
26539 extended with new ``name'' lookup methods for system databases, which
26540 includes host names, service names, user accounts, and more (@pxref{Name
26541 Service Switch, System Databases and Name Service Switch,, libc, The GNU
26542 C Library Reference Manual}).
26544 The NSS configuration specifies, for each system database, which lookup
26545 method is to be used, and how the various methods are chained
26546 together---for instance, under which circumstances NSS should try the
26547 next method in the list. The NSS configuration is given in the
26548 @code{name-service-switch} field of @code{operating-system} declarations
26549 (@pxref{operating-system Reference, @code{name-service-switch}}).
26552 @cindex .local, host name lookup
26553 As an example, the declaration below configures the NSS to use the
26554 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
26555 back-end}, which supports host name lookups over multicast DNS (mDNS)
26556 for host names ending in @code{.local}:
26559 (name-service-switch
26560 (hosts (list %files ;first, check /etc/hosts
26562 ;; If the above did not succeed, try
26563 ;; with 'mdns_minimal'.
26565 (name "mdns_minimal")
26567 ;; 'mdns_minimal' is authoritative for
26568 ;; '.local'. When it returns "not found",
26569 ;; no need to try the next methods.
26570 (reaction (lookup-specification
26571 (not-found => return))))
26573 ;; Then fall back to DNS.
26577 ;; Finally, try with the "full" 'mdns'.
26582 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
26583 contains this configuration, so you will not have to type it if all you
26584 want is to have @code{.local} host lookup working.
26586 Note that, in this case, in addition to setting the
26587 @code{name-service-switch} of the @code{operating-system} declaration,
26588 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
26589 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
26590 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
26591 to the name service cache daemon (@pxref{Base Services,
26592 @code{nscd-service}}).
26594 For convenience, the following variables provide typical NSS
26597 @defvr {Scheme Variable} %default-nss
26598 This is the default name service switch configuration, a
26599 @code{name-service-switch} object.
26602 @defvr {Scheme Variable} %mdns-host-lookup-nss
26603 This is the name service switch configuration with support for host name
26604 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
26607 The reference for name service switch configuration is given below. It
26608 is a direct mapping of the configuration file format of the C library , so
26609 please refer to the C library manual for more information (@pxref{NSS
26610 Configuration File,,, libc, The GNU C Library Reference Manual}).
26611 Compared to the configuration file format of libc NSS, it has the advantage
26612 not only of adding this warm parenthetic feel that we like, but also
26613 static checks: you will know about syntax errors and typos as soon as you
26614 run @command{guix system}.
26616 @deftp {Data Type} name-service-switch
26618 This is the data type representation the configuration of libc's name
26619 service switch (NSS). Each field below represents one of the supported
26636 The system databases handled by the NSS. Each of these fields must be a
26637 list of @code{<name-service>} objects (see below).
26641 @deftp {Data Type} name-service
26643 This is the data type representing an actual name service and the
26644 associated lookup action.
26648 A string denoting the name service (@pxref{Services in the NSS
26649 configuration,,, libc, The GNU C Library Reference Manual}).
26651 Note that name services listed here must be visible to nscd. This is
26652 achieved by passing the @code{#:name-services} argument to
26653 @code{nscd-service} the list of packages providing the needed name
26654 services (@pxref{Base Services, @code{nscd-service}}).
26657 An action specified using the @code{lookup-specification} macro
26658 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
26659 Reference Manual}). For example:
26662 (lookup-specification (unavailable => continue)
26663 (success => return))
26668 @node Initial RAM Disk
26669 @section Initial RAM Disk
26672 @cindex initial RAM disk
26673 For bootstrapping purposes, the Linux-Libre kernel is passed an
26674 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
26675 root file system as well as an initialization script. The latter is
26676 responsible for mounting the real root file system, and for loading any
26677 kernel modules that may be needed to achieve that.
26679 The @code{initrd-modules} field of an @code{operating-system}
26680 declaration allows you to specify Linux-libre kernel modules that must
26681 be available in the initrd. In particular, this is where you would list
26682 modules needed to actually drive the hard disk where your root partition
26683 is---although the default value of @code{initrd-modules} should cover
26684 most use cases. For example, assuming you need the @code{megaraid_sas}
26685 module in addition to the default modules to be able to access your root
26686 file system, you would write:
26691 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
26694 @defvr {Scheme Variable} %base-initrd-modules
26695 This is the list of kernel modules included in the initrd by default.
26698 Furthermore, if you need lower-level customization, the @code{initrd}
26699 field of an @code{operating-system} declaration allows
26700 you to specify which initrd you would like to use. The @code{(gnu
26701 system linux-initrd)} module provides three ways to build an initrd: the
26702 high-level @code{base-initrd} procedure and the low-level
26703 @code{raw-initrd} and @code{expression->initrd} procedures.
26705 The @code{base-initrd} procedure is intended to cover most common uses.
26706 For example, if you want to add a bunch of kernel modules to be loaded
26707 at boot time, you can define the @code{initrd} field of the operating
26708 system declaration like this:
26711 (initrd (lambda (file-systems . rest)
26712 ;; Create a standard initrd but set up networking
26713 ;; with the parameters QEMU expects by default.
26714 (apply base-initrd file-systems
26715 #:qemu-networking? #t
26719 The @code{base-initrd} procedure also handles common use cases that
26720 involves using the system as a QEMU guest, or as a ``live'' system with
26721 volatile root file system.
26723 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
26724 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
26725 such as trying to guess which kernel modules and packages should be included
26726 to the initrd. An example use of @code{raw-initrd} is when a user has
26727 a custom Linux kernel configuration and default kernel modules included by
26728 @code{base-initrd} are not available.
26730 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
26731 honors several options passed on the Linux kernel command line
26732 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
26733 @code{-append} option of QEMU), notably:
26736 @item --load=@var{boot}
26737 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
26738 program, once it has mounted the root file system.
26740 Guix uses this option to yield control to a boot program that runs the
26741 service activation programs and then spawns the GNU@tie{}Shepherd, the
26742 initialization system.
26744 @item --root=@var{root}
26745 Mount @var{root} as the root file system. @var{root} can be a device
26746 name like @code{/dev/sda1}, a file system label, or a file system UUID.
26747 When unspecified, the device name from the root file system of the
26748 operating system declaration is used.
26750 @item --system=@var{system}
26751 Have @file{/run/booted-system} and @file{/run/current-system} point to
26754 @item modprobe.blacklist=@var{modules}@dots{}
26755 @cindex module, black-listing
26756 @cindex black list, of kernel modules
26757 Instruct the initial RAM disk as well as the @command{modprobe} command
26758 (from the kmod package) to refuse to load @var{modules}. @var{modules}
26759 must be a comma-separated list of module names---e.g.,
26760 @code{usbkbd,9pnet}.
26763 Start a read-eval-print loop (REPL) from the initial RAM disk before it
26764 tries to load kernel modules and to mount the root file system. Our
26765 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
26766 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
26767 Manual}, for more information on Guile's REPL.
26771 Now that you know all the features that initial RAM disks produced by
26772 @code{base-initrd} and @code{raw-initrd} provide,
26773 here is how to use it and customize it further.
26776 @cindex initial RAM disk
26777 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
26778 [#:linux-modules '()] [#:mapped-devices '()] @
26779 [#:keyboard-layout #f] @
26780 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
26781 Return a derivation that builds a raw initrd. @var{file-systems} is
26782 a list of file systems to be mounted by the initrd, possibly in addition to
26783 the root file system specified on the kernel command line via @option{--root}.
26784 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
26785 @var{mapped-devices} is a list of device mappings to realize before
26786 @var{file-systems} are mounted (@pxref{Mapped Devices}).
26787 @var{helper-packages} is a list of packages to be copied in the initrd. It may
26788 include @code{e2fsck/static} or other packages needed by the initrd to check
26789 the root file system.
26791 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26792 the desired console keyboard layout. This is done before @var{mapped-devices}
26793 are set up and before @var{file-systems} are mounted such that, should the
26794 user need to enter a passphrase or use the REPL, this happens using the
26795 intended keyboard layout.
26797 When @var{qemu-networking?} is true, set up networking with the standard QEMU
26798 parameters. When @var{virtio?} is true, load additional modules so that the
26799 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
26801 When @var{volatile-root?} is true, the root file system is writable but any changes
26805 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
26806 [#:mapped-devices '()] [#:keyboard-layout #f] @
26807 [#:qemu-networking? #f] [#:volatile-root? #f] @
26808 [#:linux-modules '()]
26809 Return as a file-like object a generic initrd, with kernel
26810 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
26811 mounted by the initrd, possibly in addition to the root file system specified
26812 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
26813 mappings to realize before @var{file-systems} are mounted.
26815 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26816 the desired console keyboard layout. This is done before @var{mapped-devices}
26817 are set up and before @var{file-systems} are mounted such that, should the
26818 user need to enter a passphrase or use the REPL, this happens using the
26819 intended keyboard layout.
26821 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
26823 The initrd is automatically populated with all the kernel modules necessary
26824 for @var{file-systems} and for the given options. Additional kernel
26825 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
26826 loaded at boot time in the order in which they appear.
26829 Needless to say, the initrds we produce and use embed a
26830 statically-linked Guile, and the initialization program is a Guile
26831 program. That gives a lot of flexibility. The
26832 @code{expression->initrd} procedure builds such an initrd, given the
26833 program to run in that initrd.
26835 @deffn {Scheme Procedure} expression->initrd @var{exp} @
26836 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
26837 Return as a file-like object a Linux initrd (a gzipped cpio archive)
26838 containing @var{guile} and that evaluates @var{exp}, a G-expression,
26839 upon booting. All the derivations referenced by @var{exp} are
26840 automatically copied to the initrd.
26843 @node Bootloader Configuration
26844 @section Bootloader Configuration
26847 @cindex boot loader
26849 The operating system supports multiple bootloaders. The bootloader is
26850 configured using @code{bootloader-configuration} declaration. All the
26851 fields of this structure are bootloader agnostic except for one field,
26852 @code{bootloader} that indicates the bootloader to be configured and
26855 Some of the bootloaders do not honor every field of
26856 @code{bootloader-configuration}. For instance, the extlinux
26857 bootloader does not support themes and thus ignores the @code{theme}
26860 @deftp {Data Type} bootloader-configuration
26861 The type of a bootloader configuration declaration.
26865 @item @code{bootloader}
26866 @cindex EFI, bootloader
26867 @cindex UEFI, bootloader
26868 @cindex BIOS, bootloader
26869 The bootloader to use, as a @code{bootloader} object. For now
26870 @code{grub-bootloader}, @code{grub-efi-bootloader},
26871 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
26873 @vindex grub-efi-bootloader
26874 @code{grub-efi-bootloader} allows to boot on modern systems using the
26875 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
26876 use if the installation image contains a @file{/sys/firmware/efi} directory
26877 when you boot it on your system.
26879 @vindex grub-bootloader
26880 @code{grub-bootloader} allows you to boot in particular Intel-based machines
26881 in ``legacy'' BIOS mode.
26883 @cindex ARM, bootloaders
26884 @cindex AArch64, bootloaders
26885 Available bootloaders are described in @code{(gnu bootloader @dots{})}
26886 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
26887 of bootloaders for a wide range of ARM and AArch64 systems, using the
26888 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
26890 @item @code{target}
26891 This is a string denoting the target onto which to install the
26894 The interpretation depends on the bootloader in question. For
26895 @code{grub-bootloader}, for example, it should be a device name understood by
26896 the bootloader @command{installer} command, such as @code{/dev/sda} or
26897 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
26898 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
26899 system, usually @file{/boot/efi}.
26901 @item @code{menu-entries} (default: @code{()})
26902 A possibly empty list of @code{menu-entry} objects (see below), denoting
26903 entries to appear in the bootloader menu, in addition to the current
26904 system entry and the entry pointing to previous system generations.
26906 @item @code{default-entry} (default: @code{0})
26907 The index of the default boot menu entry. Index 0 is for the entry of the
26910 @item @code{timeout} (default: @code{5})
26911 The number of seconds to wait for keyboard input before booting. Set to
26912 0 to boot immediately, and to -1 to wait indefinitely.
26914 @cindex keyboard layout, for the bootloader
26915 @item @code{keyboard-layout} (default: @code{#f})
26916 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
26917 layout, usually US@tie{}English (``qwerty'').
26919 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
26923 This option is currently ignored by bootloaders other than @code{grub} and
26927 @item @code{theme} (default: @var{#f})
26928 The bootloader theme object describing the theme to use. If no theme
26929 is provided, some bootloaders might use a default theme, that's true
26932 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
26933 The output terminals used for the bootloader boot menu, as a list of
26934 symbols. GRUB accepts the values: @code{console}, @code{serial},
26935 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
26936 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
26937 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
26938 configuration,,, grub,GNU GRUB manual}).
26940 @item @code{terminal-inputs} (default: @code{'()})
26941 The input terminals used for the bootloader boot menu, as a list of
26942 symbols. For GRUB, the default is the native platform terminal as
26943 determined at run-time. GRUB accepts the values: @code{console},
26944 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
26945 @code{usb_keyboard}. This field corresponds to the GRUB variable
26946 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
26949 @item @code{serial-unit} (default: @code{#f})
26950 The serial unit used by the bootloader, as an integer from 0 to 3.
26951 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
26952 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26954 @item @code{serial-speed} (default: @code{#f})
26955 The speed of the serial interface, as an integer. For GRUB, the
26956 default value is chosen at run-time; currently GRUB chooses
26957 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26964 Should you want to list additional boot menu entries @i{via} the
26965 @code{menu-entries} field above, you will need to create them with the
26966 @code{menu-entry} form. For example, imagine you want to be able to
26967 boot another distro (hard to imagine!), you can define a menu entry
26972 (label "The Other Distro")
26973 (linux "/boot/old/vmlinux-2.6.32")
26974 (linux-arguments '("root=/dev/sda2"))
26975 (initrd "/boot/old/initrd"))
26980 @deftp {Data Type} menu-entry
26981 The type of an entry in the bootloader menu.
26986 The label to show in the menu---e.g., @code{"GNU"}.
26989 The Linux kernel image to boot, for example:
26992 (file-append linux-libre "/bzImage")
26995 For GRUB, it is also possible to specify a device explicitly in the
26996 file path using GRUB's device naming convention (@pxref{Naming
26997 convention,,, grub, GNU GRUB manual}), for example:
27000 "(hd0,msdos1)/boot/vmlinuz"
27003 If the device is specified explicitly as above, then the @code{device}
27004 field is ignored entirely.
27006 @item @code{linux-arguments} (default: @code{()})
27007 The list of extra Linux kernel command-line arguments---e.g.,
27008 @code{("console=ttyS0")}.
27010 @item @code{initrd}
27011 A G-Expression or string denoting the file name of the initial RAM disk
27012 to use (@pxref{G-Expressions}).
27013 @item @code{device} (default: @code{#f})
27014 The device where the kernel and initrd are to be found---i.e., for GRUB,
27015 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
27017 This may be a file system label (a string), a file system UUID (a
27018 bytevector, @pxref{File Systems}), or @code{#f}, in which case
27019 the bootloader will search the device containing the file specified by
27020 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
27021 must @emph{not} be an OS device name such as @file{/dev/sda1}.
27029 @c FIXME: Write documentation once it's stable.
27030 For now only GRUB has theme support. GRUB themes are created using
27031 the @code{grub-theme} form, which is not fully documented yet.
27033 @deftp {Data Type} grub-theme
27034 Data type representing the configuration of the GRUB theme.
27037 @item @code{gfxmode} (default: @code{'("auto")})
27038 The GRUB @code{gfxmode} to set (a list of screen resolution strings, see
27039 @pxref{gfxmode,,, grub, GNU GRUB manual}).
27043 @deffn {Scheme Procedure} grub-theme
27044 Return the default GRUB theme used by the operating system if no
27045 @code{theme} field is specified in @code{bootloader-configuration}
27048 It comes with a fancy background image displaying the GNU and Guix
27052 For example, to override the default resolution, you may use something
27057 (bootloader-configuration
27060 (inherit (grub-theme))
27061 (gfxmode '("1024x786x32" "auto"))))))
27064 @node Invoking guix system
27065 @section Invoking @code{guix system}
27067 Once you have written an operating system declaration as seen in the
27068 previous section, it can be @dfn{instantiated} using the @command{guix
27069 system} command. The synopsis is:
27072 guix system @var{options}@dots{} @var{action} @var{file}
27075 @var{file} must be the name of a file containing an
27076 @code{operating-system} declaration. @var{action} specifies how the
27077 operating system is instantiated. Currently the following values are
27082 Display available service type definitions that match the given regular
27083 expressions, sorted by relevance:
27089 $ guix system search console
27090 name: console-fonts
27091 location: gnu/services/base.scm:806:2
27092 extends: shepherd-root
27093 description: Install the given fonts on the specified ttys (fonts are per
27094 + virtual console on GNU/Linux). The value of this service is a list of
27095 + tty/font pairs. The font can be the name of a font provided by the `kbd'
27096 + package or any valid argument to `setfont', as in this example:
27098 + '(("tty1" . "LatGrkCyr-8x16")
27099 + ("tty2" . (file-append
27101 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
27102 + ("tty3" . (file-append
27104 + "/share/consolefonts/ter-132n"))) ; for HDPI
27108 location: gnu/services/base.scm:1190:2
27109 extends: shepherd-root
27110 description: Provide console login using the `mingetty' program.
27114 location: gnu/services/base.scm:860:2
27116 description: Provide a console log-in service as specified by its
27117 + configuration value, a `login-configuration' object.
27123 As for @command{guix package --search}, the result is written in
27124 @code{recutils} format, which makes it easy to filter the output
27125 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
27128 Build the operating system described in @var{file}, activate it, and
27129 switch to it@footnote{This action (and the related actions
27130 @code{switch-generation} and @code{roll-back}) are usable only on
27131 systems already running Guix System.}.
27134 @c The paragraph below refers to the problem discussed at
27135 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
27136 It is highly recommended to run @command{guix pull} once before you run
27137 @command{guix system reconfigure} for the first time (@pxref{Invoking
27138 guix pull}). Failing to do that you would see an older version of Guix
27139 once @command{reconfigure} has completed.
27142 This effects all the configuration specified in @var{file}: user
27143 accounts, system services, global package list, setuid programs, etc.
27144 The command starts system services specified in @var{file} that are not
27145 currently running; if a service is currently running this command will
27146 arrange for it to be upgraded the next time it is stopped (e.g.@: by
27147 @code{herd stop X} or @code{herd restart X}).
27149 This command creates a new generation whose number is one greater than
27150 the current generation (as reported by @command{guix system
27151 list-generations}). If that generation already exists, it will be
27152 overwritten. This behavior mirrors that of @command{guix package}
27153 (@pxref{Invoking guix package}).
27155 It also adds a bootloader menu entry for the new OS configuration,
27156 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
27157 entries for older configurations to a submenu, allowing you to choose
27158 an older system generation at boot time should you need it.
27160 @cindex provenance tracking, of the operating system
27161 Upon completion, the new system is deployed under
27162 @file{/run/current-system}. This directory contains @dfn{provenance
27163 meta-data}: the list of channels in use (@pxref{Channels}) and
27164 @var{file} itself, when available. This information is useful should
27165 you later want to inspect how this particular generation was built.
27167 In fact, assuming @var{file} is self-contained, you can later rebuild
27168 generation @var{n} of your operating system with:
27171 guix time-machine \
27172 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
27173 system reconfigure \
27174 /var/guix/profiles/system-@var{n}-link/configuration.scm
27177 You can think of it as some sort of built-in version control! Your
27178 system is not just a binary artifact: @emph{it carries its own source}.
27179 @xref{Service Reference, @code{provenance-service-type}}, for more
27180 information on provenance tracking.
27182 @item switch-generation
27183 @cindex generations
27184 Switch to an existing system generation. This action atomically
27185 switches the system profile to the specified system generation. It
27186 also rearranges the system's existing bootloader menu entries. It
27187 makes the menu entry for the specified system generation the default,
27188 and it moves the entries for the other generations to a submenu, if
27189 supported by the bootloader being used. The next time the system
27190 boots, it will use the specified system generation.
27192 The bootloader itself is not being reinstalled when using this
27193 command. Thus, the installed bootloader is used with an updated
27194 configuration file.
27196 The target generation can be specified explicitly by its generation
27197 number. For example, the following invocation would switch to system
27201 guix system switch-generation 7
27204 The target generation can also be specified relative to the current
27205 generation with the form @code{+N} or @code{-N}, where @code{+3} means
27206 ``3 generations ahead of the current generation,'' and @code{-1} means
27207 ``1 generation prior to the current generation.'' When specifying a
27208 negative value such as @code{-1}, you must precede it with @code{--} to
27209 prevent it from being parsed as an option. For example:
27212 guix system switch-generation -- -1
27215 Currently, the effect of invoking this action is @emph{only} to switch
27216 the system profile to an existing generation and rearrange the
27217 bootloader menu entries. To actually start using the target system
27218 generation, you must reboot after running this action. In the future,
27219 it will be updated to do the same things as @command{reconfigure},
27220 like activating and deactivating services.
27222 This action will fail if the specified generation does not exist.
27225 @cindex rolling back
27226 Switch to the preceding system generation. The next time the system
27227 boots, it will use the preceding system generation. This is the inverse
27228 of @command{reconfigure}, and it is exactly the same as invoking
27229 @command{switch-generation} with an argument of @code{-1}.
27231 Currently, as with @command{switch-generation}, you must reboot after
27232 running this action to actually start using the preceding system
27235 @item delete-generations
27236 @cindex deleting system generations
27237 @cindex saving space
27238 Delete system generations, making them candidates for garbage collection
27239 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
27242 This works in the same way as @samp{guix package --delete-generations}
27243 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
27244 arguments, all system generations but the current one are deleted:
27247 guix system delete-generations
27250 You can also select the generations you want to delete. The example below
27251 deletes all the system generations that are more than two month old:
27254 guix system delete-generations 2m
27257 Running this command automatically reinstalls the bootloader with an updated
27258 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
27259 longer lists the generations that have been deleted.
27262 Build the derivation of the operating system, which includes all the
27263 configuration files and programs needed to boot and run the system.
27264 This action does not actually install anything.
27267 Populate the given directory with all the files necessary to run the
27268 operating system specified in @var{file}. This is useful for first-time
27269 installations of Guix System. For instance:
27272 guix system init my-os-config.scm /mnt
27275 copies to @file{/mnt} all the store items required by the configuration
27276 specified in @file{my-os-config.scm}. This includes configuration
27277 files, packages, and so on. It also creates other essential files
27278 needed for the system to operate correctly---e.g., the @file{/etc},
27279 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
27281 This command also installs bootloader on the target specified in
27282 @file{my-os-config}, unless the @option{--no-bootloader} option was
27286 @cindex virtual machine
27288 @anchor{guix system vm}
27289 Build a virtual machine that contains the operating system declared in
27290 @var{file}, and return a script to run that virtual machine (VM).
27293 The @code{vm} action and others below
27294 can use KVM support in the Linux-libre kernel. Specifically, if the
27295 machine has hardware virtualization support, the corresponding
27296 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
27297 must exist and be readable and writable by the user and by the
27298 build users of the daemon (@pxref{Build Environment Setup}).
27301 Arguments given to the script are passed to QEMU as in the example
27302 below, which enables networking and requests 1@tie{}GiB of RAM for the
27306 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
27309 The VM shares its store with the host system.
27311 Additional file systems can be shared between the host and the VM using
27312 the @option{--share} and @option{--expose} command-line options: the former
27313 specifies a directory to be shared with write access, while the latter
27314 provides read-only access to the shared directory.
27316 The example below creates a VM in which the user's home directory is
27317 accessible read-only, and where the @file{/exchange} directory is a
27318 read-write mapping of @file{$HOME/tmp} on the host:
27321 guix system vm my-config.scm \
27322 --expose=$HOME --share=$HOME/tmp=/exchange
27325 On GNU/Linux, the default is to boot directly to the kernel; this has
27326 the advantage of requiring only a very tiny root disk image since the
27327 store of the host can then be mounted.
27329 The @option{--full-boot} option forces a complete boot sequence, starting
27330 with the bootloader. This requires more disk space since a root image
27331 containing at least the kernel, initrd, and bootloader data files must
27332 be created. The @option{--image-size} option can be used to specify the
27335 @cindex System images, creation in various formats
27336 @cindex Creating system images in various formats
27339 @itemx docker-image
27340 Return a virtual machine, disk image, or Docker image of the operating
27341 system declared in @var{file} that stands alone. By default,
27342 @command{guix system} estimates the size of the image needed to store
27343 the system, but you can use the @option{--image-size} option to specify
27344 a value. Docker images are built to contain exactly what they need, so
27345 the @option{--image-size} option is ignored in the case of
27346 @code{docker-image}.
27348 You can specify the root file system type by using the
27349 @option{--file-system-type} option. It defaults to @code{ext4}.
27351 When using @code{vm-image}, the returned image is in qcow2 format, which
27352 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
27353 for more information on how to run the image in a virtual machine.
27355 When using @code{disk-image}, a raw disk image is produced; it can be
27356 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
27357 the device corresponding to a USB stick, one can copy the image to it
27358 using the following command:
27361 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
27364 When using @code{docker-image}, a Docker image is produced. Guix builds
27365 the image from scratch, not from a pre-existing Docker base image. As a
27366 result, it contains @emph{exactly} what you define in the operating
27367 system configuration file. You can then load the image and launch a
27368 Docker container using commands like the following:
27371 image_id="`docker load < guix-system-docker-image.tar.gz`"
27372 container_id="`docker create $image_id`"
27373 docker start $container_id
27376 This command starts a new Docker container from the specified image. It
27377 will boot the Guix system in the usual manner, which means it will
27378 start any services you have defined in the operating system
27379 configuration. You can get an interactive shell running in the container
27380 using @command{docker exec}:
27383 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
27386 Depending on what you run in the Docker container, it
27387 may be necessary to give the container additional permissions. For
27388 example, if you intend to build software using Guix inside of the Docker
27389 container, you may need to pass the @option{--privileged} option to
27390 @code{docker create}.
27392 Last, the @option{--network} option applies to @command{guix system
27393 docker-image}: it produces an image where network is supposedly shared
27394 with the host, and thus without services like nscd or NetworkManager.
27397 Return a script to run the operating system declared in @var{file}
27398 within a container. Containers are a set of lightweight isolation
27399 mechanisms provided by the kernel Linux-libre. Containers are
27400 substantially less resource-demanding than full virtual machines since
27401 the kernel, shared objects, and other resources can be shared with the
27402 host system; this also means they provide thinner isolation.
27404 Currently, the script must be run as root in order to support more than
27405 a single user and group. The container shares its store with the host
27408 As with the @code{vm} action (@pxref{guix system vm}), additional file
27409 systems to be shared between the host and container can be specified
27410 using the @option{--share} and @option{--expose} options:
27413 guix system container my-config.scm \
27414 --expose=$HOME --share=$HOME/tmp=/exchange
27418 This option requires Linux-libre 3.19 or newer.
27423 @var{options} can contain any of the common build options (@pxref{Common
27424 Build Options}). In addition, @var{options} can contain one of the
27428 @item --expression=@var{expr}
27429 @itemx -e @var{expr}
27430 Consider the operating-system @var{expr} evaluates to.
27431 This is an alternative to specifying a file which evaluates to an
27433 This is used to generate the Guix system installer @pxref{Building the
27434 Installation Image}).
27436 @item --system=@var{system}
27437 @itemx -s @var{system}
27438 Attempt to build for @var{system} instead of the host system type.
27439 This works as per @command{guix build} (@pxref{Invoking guix build}).
27443 Return the derivation file name of the given operating system without
27446 @cindex provenance tracking, of the operating system
27447 @item --save-provenance
27448 As discussed above, @command{guix system init} and @command{guix system
27449 reconfigure} always save provenance information @i{via} a dedicated
27450 service (@pxref{Service Reference, @code{provenance-service-type}}).
27451 However, other commands don't do that by default. If you wish to, say,
27452 create a virtual machine image that contains provenance information, you
27456 guix system vm-image --save-provenance config.scm
27459 That way, the resulting image will effectively ``embed its own source''
27460 in the form of meta-data in @file{/run/current-system}. With that
27461 information, one can rebuild the image to make sure it really contains
27462 what it pretends to contain; or they could use that to derive a variant
27465 @item --file-system-type=@var{type}
27466 @itemx -t @var{type}
27467 For the @code{disk-image} action, create a file system of the given
27468 @var{type} on the image.
27470 When this option is omitted, @command{guix system} uses @code{ext4}.
27472 @cindex ISO-9660 format
27473 @cindex CD image format
27474 @cindex DVD image format
27475 @option{--file-system-type=iso9660} produces an ISO-9660 image, suitable
27476 for burning on CDs and DVDs.
27478 @item --image-size=@var{size}
27479 For the @code{vm-image} and @code{disk-image} actions, create an image
27480 of the given @var{size}. @var{size} may be a number of bytes, or it may
27481 include a unit as a suffix (@pxref{Block size, size specifications,,
27482 coreutils, GNU Coreutils}).
27484 When this option is omitted, @command{guix system} computes an estimate
27485 of the image size as a function of the size of the system declared in
27490 For the @code{container} action, allow containers to access the host network,
27491 that is, do not create a network namespace.
27493 @item --root=@var{file}
27494 @itemx -r @var{file}
27495 Make @var{file} a symlink to the result, and register it as a garbage
27498 @item --skip-checks
27499 Skip pre-installation safety checks.
27501 By default, @command{guix system init} and @command{guix system
27502 reconfigure} perform safety checks: they make sure the file systems that
27503 appear in the @code{operating-system} declaration actually exist
27504 (@pxref{File Systems}), and that any Linux kernel modules that may be
27505 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
27506 RAM Disk}). Passing this option skips these tests altogether.
27509 @cindex on-error strategy
27510 @cindex error strategy
27511 @item --on-error=@var{strategy}
27512 Apply @var{strategy} when an error occurs when reading @var{file}.
27513 @var{strategy} may be one of the following:
27516 @item nothing-special
27517 Report the error concisely and exit. This is the default strategy.
27520 Likewise, but also display a backtrace.
27523 Report the error and enter Guile's debugger. From there, you can run
27524 commands such as @code{,bt} to get a backtrace, @code{,locals} to
27525 display local variable values, and more generally inspect the state of the
27526 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
27527 a list of available debugging commands.
27531 Once you have built, configured, re-configured, and re-re-configured
27532 your Guix installation, you may find it useful to list the operating
27533 system generations available on disk---and that you can choose from the
27534 bootloader boot menu:
27539 Describe the current system generation: its file name, the kernel and
27540 bootloader used, etc., as well as provenance information when available.
27542 @item list-generations
27543 List a summary of each generation of the operating system available on
27544 disk, in a human-readable way. This is similar to the
27545 @option{--list-generations} option of @command{guix package}
27546 (@pxref{Invoking guix package}).
27548 Optionally, one can specify a pattern, with the same syntax that is used
27549 in @command{guix package --list-generations}, to restrict the list of
27550 generations displayed. For instance, the following command displays
27551 generations that are up to 10 days old:
27554 $ guix system list-generations 10d
27559 The @command{guix system} command has even more to offer! The following
27560 sub-commands allow you to visualize how your system services relate to
27563 @anchor{system-extension-graph}
27566 @item extension-graph
27567 Emit in Dot/Graphviz format to standard output the @dfn{service
27568 extension graph} of the operating system defined in @var{file}
27569 (@pxref{Service Composition}, for more information on service
27575 $ guix system extension-graph @var{file} | xdot -
27578 shows the extension relations among services.
27580 @anchor{system-shepherd-graph}
27581 @item shepherd-graph
27582 Emit in Dot/Graphviz format to standard output the @dfn{dependency
27583 graph} of shepherd services of the operating system defined in
27584 @var{file}. @xref{Shepherd Services}, for more information and for an
27589 @node Invoking guix deploy
27590 @section Invoking @code{guix deploy}
27592 We've already seen @code{operating-system} declarations used to manage a
27593 machine's configuration locally. Suppose you need to configure multiple
27594 machines, though---perhaps you're managing a service on the web that's
27595 comprised of several servers. @command{guix deploy} enables you to use those
27596 same @code{operating-system} declarations to manage multiple remote hosts at
27597 once as a logical ``deployment''.
27600 The functionality described in this section is still under development
27601 and is subject to change. Get in touch with us on
27602 @email{guix-devel@@gnu.org}!
27606 guix deploy @var{file}
27609 Such an invocation will deploy the machines that the code within @var{file}
27610 evaluates to. As an example, @var{file} might contain a definition like this:
27613 ;; This is a Guix deployment of a "bare bones" setup, with
27614 ;; no X11 display server, to a machine with an SSH daemon
27615 ;; listening on localhost:2222. A configuration such as this
27616 ;; may be appropriate for virtual machine with ports
27617 ;; forwarded to the host's loopback interface.
27619 (use-service-modules networking ssh)
27620 (use-package-modules bootloaders)
27624 (host-name "gnu-deployed")
27625 (timezone "Etc/UTC")
27626 (bootloader (bootloader-configuration
27627 (bootloader grub-bootloader)
27628 (target "/dev/vda")
27629 (terminal-outputs '(console))))
27630 (file-systems (cons (file-system
27632 (device "/dev/vda1")
27634 %base-file-systems))
27636 (append (list (service dhcp-client-service-type)
27637 (service openssh-service-type
27638 (openssh-configuration
27639 (permit-root-login #t)
27640 (allow-empty-passwords? #t))))
27644 (operating-system %system)
27645 (environment managed-host-environment-type)
27646 (configuration (machine-ssh-configuration
27647 (host-name "localhost")
27648 (system "x86_64-linux")
27650 (identity "./id_rsa")
27654 The file should evaluate to a list of @var{machine} objects. This example,
27655 upon being deployed, will create a new generation on the remote system
27656 realizing the @code{operating-system} declaration @code{%system}.
27657 @code{environment} and @code{configuration} specify how the machine should be
27658 provisioned---that is, how the computing resources should be created and
27659 managed. The above example does not create any resources, as a
27660 @code{'managed-host} is a machine that is already running the Guix system and
27661 available over the network. This is a particularly simple case; a more
27662 complex deployment may involve, for example, starting virtual machines through
27663 a Virtual Private Server (VPS) provider. In such a case, a different
27664 @var{environment} type would be used.
27666 Do note that you first need to generate a key pair on the coordinator machine
27667 to allow the daemon to export signed archives of files from the store
27668 (@pxref{Invoking guix archive}).
27671 # guix archive --generate-key
27675 Each target machine must authorize the key of the master machine so that it
27676 accepts store items it receives from the coordinator:
27679 # guix archive --authorize < coordinator-public-key.txt
27682 @code{user}, in this example, specifies the name of the user account to log in
27683 as to perform the deployment. Its default value is @code{root}, but root
27684 login over SSH may be forbidden in some cases. To work around this,
27685 @command{guix deploy} can log in as an unprivileged user and employ
27686 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
27687 currently installed on the remote and can be invoked non-interactively as
27688 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
27689 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
27690 be accomplished with the following operating system configuration snippet:
27694 (gnu system)) ;for %sudoers-specification
27696 (define %user "username")
27701 (plain-file "sudoers"
27702 (string-append (plain-file-content %sudoers-specification)
27703 (format #f "~a ALL = NOPASSWD: ALL~%"
27708 For more information regarding the format of the @file{sudoers} file,
27709 consult @command{man sudoers}.
27711 @deftp {Data Type} machine
27712 This is the data type representing a single machine in a heterogeneous Guix
27716 @item @code{operating-system}
27717 The object of the operating system configuration to deploy.
27719 @item @code{environment}
27720 An @code{environment-type} describing how the machine should be provisioned.
27722 @item @code{configuration} (default: @code{#f})
27723 An object describing the configuration for the machine's @code{environment}.
27724 If the @code{environment} has a default configuration, @code{#f} may be used.
27725 If @code{#f} is used for an environment with no default configuration,
27726 however, an error will be thrown.
27730 @deftp {Data Type} machine-ssh-configuration
27731 This is the data type representing the SSH client parameters for a machine
27732 with an @code{environment} of @code{managed-host-environment-type}.
27735 @item @code{host-name}
27736 @item @code{build-locally?} (default: @code{#t})
27737 If false, system derivations will be built on the machine being deployed to.
27738 @item @code{system}
27739 The system type describing the architecture of the machine being deployed
27740 to---e.g., @code{"x86_64-linux"}.
27741 @item @code{authorize?} (default: @code{#t})
27742 If true, the coordinator's signing key will be added to the remote's ACL
27744 @item @code{port} (default: @code{22})
27745 @item @code{user} (default: @code{"root"})
27746 @item @code{identity} (default: @code{#f})
27747 If specified, the path to the SSH private key to use to authenticate with the
27750 @item @code{host-key} (default: @code{#f})
27751 This should be the SSH host key of the machine, which looks like this:
27754 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
27757 When @code{host-key} is @code{#f}, the server is authenticated against
27758 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
27764 @deftp {Data Type} digital-ocean-configuration
27765 This is the data type describing the Droplet that should be created for a
27766 machine with an @code{environment} of @code{digital-ocean-environment-type}.
27769 @item @code{ssh-key}
27770 The path to the SSH private key to use to authenticate with the remote
27771 host. In the future, this field may not exist.
27773 A list of string ``tags'' that uniquely identify the machine. Must be given
27774 such that no two machines in the deployment have the same set of tags.
27775 @item @code{region}
27776 A Digital Ocean region slug, such as @code{"nyc3"}.
27778 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
27779 @item @code{enable-ipv6?}
27780 Whether or not the droplet should be created with IPv6 networking.
27784 @node Running Guix in a VM
27785 @section Running Guix in a Virtual Machine
27787 @cindex virtual machine
27788 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
27790 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
27791 This image is a compressed image in QCOW format. You will first need to
27792 decompress with @command{xz -d}, and then you can pass it to an emulator such
27793 as QEMU (see below for details).
27795 This image boots the Xfce graphical environment and it contains some
27796 commonly-used tools. You can install more software in the image by running
27797 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
27798 also reconfigure the system based on its initial configuration file available
27799 as @file{/run/current-system/configuration.scm} (@pxref{Using the
27800 Configuration System}).
27802 Instead of using this pre-built image, one can also build their own virtual
27803 machine image using @command{guix system vm-image} (@pxref{Invoking guix
27804 system}). The returned image is in qcow2 format, which the
27805 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
27808 If you built your own image, you must copy it out of the store
27809 (@pxref{The Store}) and give yourself permission to write to the copy
27810 before you can use it. When invoking QEMU, you must choose a system
27811 emulator that is suitable for your hardware platform. Here is a minimal
27812 QEMU invocation that will boot the result of @command{guix system
27813 vm-image} on x86_64 hardware:
27816 $ qemu-system-x86_64 \
27817 -nic user,model=virtio-net-pci \
27818 -enable-kvm -m 1024 \
27819 -device virtio-blk,drive=myhd \
27820 -drive if=none,file=/tmp/qemu-image,id=myhd
27823 Here is what each of these options means:
27826 @item qemu-system-x86_64
27827 This specifies the hardware platform to emulate. This should match the
27830 @item -nic user,model=virtio-net-pci
27831 Enable the unprivileged user-mode network stack. The guest OS can
27832 access the host but not vice versa. This is the simplest way to get the
27833 guest OS online. @code{model} specifies which network device to emulate:
27834 @code{virtio-net-pci} is a special device made for virtualized operating
27835 systems and recommended for most uses. Assuming your hardware platform is
27836 x86_64, you can get a list of available NIC models by running
27837 @command{qemu-system-x86_64 -nic model=help}.
27840 If your system has hardware virtualization extensions, enabling the
27841 virtual machine support (KVM) of the Linux kernel will make things run
27844 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
27846 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
27847 which may be insufficient for some operations.
27849 @item -device virtio-blk,drive=myhd
27850 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
27851 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
27852 better performance than if it were emulating a complete disk drive. See the
27853 QEMU and KVM documentation for more info.
27855 @item -drive if=none,file=/tmp/qemu-image,id=myhd
27856 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
27857 the ``myhd'' drive.
27860 The default @command{run-vm.sh} script that is returned by an invocation of
27861 @command{guix system vm} does not add a @command{-nic user} flag by default.
27862 To get network access from within the vm add the @code{(dhcp-client-service)}
27863 to your system definition and start the VM using
27864 @command{`guix system vm config.scm` -nic user}. An important caveat of using
27865 @command{-nic user} for networking is that @command{ping} will not work, because
27866 it uses the ICMP protocol. You'll have to use a different command to check for
27867 network connectivity, for example @command{guix download}.
27869 @subsection Connecting Through SSH
27873 To enable SSH inside a VM you need to add an SSH server like
27874 @code{openssh-service-type} to your VM (@pxref{Networking Services,
27875 @code{openssh-service-type}}). In addition you need to forward the SSH port,
27876 22 by default, to the host. You can do this with
27879 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
27882 To connect to the VM you can run
27885 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
27888 The @command{-p} tells @command{ssh} the port you want to connect to.
27889 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
27890 every time you modify your @command{config.scm} file and the
27891 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
27892 connection to an unknown host every time you connect.
27894 @subsection Using @command{virt-viewer} with Spice
27896 As an alternative to the default @command{qemu} graphical client you can
27897 use the @command{remote-viewer} from the @command{virt-viewer} package. To
27898 connect pass the @command{-spice port=5930,disable-ticketing} flag to
27899 @command{qemu}. See previous section for further information on how to do this.
27901 Spice also allows you to do some nice stuff like share your clipboard with your
27902 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
27905 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
27906 -chardev spicevmc,name=vdagent,id=vdagent
27907 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
27908 name=com.redhat.spice.0
27911 You'll also need to add the @code{(spice-vdagent-service)} to your
27912 system definition (@pxref{Miscellaneous Services, Spice service}).
27914 @node Defining Services
27915 @section Defining Services
27917 The previous sections show the available services and how one can combine
27918 them in an @code{operating-system} declaration. But how do we define
27919 them in the first place? And what is a service anyway?
27922 * Service Composition:: The model for composing services.
27923 * Service Types and Services:: Types and services.
27924 * Service Reference:: API reference.
27925 * Shepherd Services:: A particular type of service.
27928 @node Service Composition
27929 @subsection Service Composition
27933 Here we define a @dfn{service} as, broadly, something that extends the
27934 functionality of the operating system. Often a service is a process---a
27935 @dfn{daemon}---started when the system boots: a secure shell server, a
27936 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
27937 whose execution can be triggered by another daemon---e.g., an FTP server
27938 started by @command{inetd} or a D-Bus service activated by
27939 @command{dbus-daemon}. Occasionally, a service does not map to a
27940 daemon. For instance, the ``account'' service collects user accounts
27941 and makes sure they exist when the system runs; the ``udev'' service
27942 collects device management rules and makes them available to the eudev
27943 daemon; the @file{/etc} service populates the @file{/etc} directory
27946 @cindex service extensions
27947 Guix system services are connected by @dfn{extensions}. For instance, the
27948 secure shell service @emph{extends} the Shepherd---the
27949 initialization system, running as PID@tie{}1---by giving it the command
27950 lines to start and stop the secure shell daemon (@pxref{Networking
27951 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
27952 service by passing it its @file{.service} specification, and extends the
27953 udev service by passing it device management rules (@pxref{Desktop
27954 Services, @code{upower-service}}); the Guix daemon service extends the
27955 Shepherd by passing it the command lines to start and stop the daemon,
27956 and extends the account service by passing it a list of required build
27957 user accounts (@pxref{Base Services}).
27959 All in all, services and their ``extends'' relations form a directed
27960 acyclic graph (DAG). If we represent services as boxes and extensions
27961 as arrows, a typical system might provide something like this:
27963 @image{images/service-graph,,5in,Typical service extension graph.}
27965 @cindex system service
27966 At the bottom, we see the @dfn{system service}, which produces the
27967 directory containing everything to run and boot the system, as returned
27968 by the @command{guix system build} command. @xref{Service Reference},
27969 to learn about the other service types shown here.
27970 @xref{system-extension-graph, the @command{guix system extension-graph}
27971 command}, for information on how to generate this representation for a
27972 particular operating system definition.
27974 @cindex service types
27975 Technically, developers can define @dfn{service types} to express these
27976 relations. There can be any number of services of a given type on the
27977 system---for instance, a system running two instances of the GNU secure
27978 shell server (lsh) has two instances of @code{lsh-service-type}, with
27979 different parameters.
27981 The following section describes the programming interface for service
27982 types and services.
27984 @node Service Types and Services
27985 @subsection Service Types and Services
27987 A @dfn{service type} is a node in the DAG described above. Let us start
27988 with a simple example, the service type for the Guix build daemon
27989 (@pxref{Invoking guix-daemon}):
27992 (define guix-service-type
27996 (list (service-extension shepherd-root-service-type guix-shepherd-service)
27997 (service-extension account-service-type guix-accounts)
27998 (service-extension activation-service-type guix-activation)))
27999 (default-value (guix-configuration))))
28003 It defines three things:
28007 A name, whose sole purpose is to make inspection and debugging easier.
28010 A list of @dfn{service extensions}, where each extension designates the
28011 target service type and a procedure that, given the parameters of the
28012 service, returns a list of objects to extend the service of that type.
28014 Every service type has at least one service extension. The only
28015 exception is the @dfn{boot service type}, which is the ultimate service.
28018 Optionally, a default value for instances of this type.
28021 In this example, @code{guix-service-type} extends three services:
28024 @item shepherd-root-service-type
28025 The @code{guix-shepherd-service} procedure defines how the Shepherd
28026 service is extended. Namely, it returns a @code{<shepherd-service>}
28027 object that defines how @command{guix-daemon} is started and stopped
28028 (@pxref{Shepherd Services}).
28030 @item account-service-type
28031 This extension for this service is computed by @code{guix-accounts},
28032 which returns a list of @code{user-group} and @code{user-account}
28033 objects representing the build user accounts (@pxref{Invoking
28036 @item activation-service-type
28037 Here @code{guix-activation} is a procedure that returns a gexp, which is
28038 a code snippet to run at ``activation time''---e.g., when the service is
28042 A service of this type is instantiated like this:
28045 (service guix-service-type
28046 (guix-configuration
28048 (use-substitutes? #f)))
28051 The second argument to the @code{service} form is a value representing
28052 the parameters of this specific service instance.
28053 @xref{guix-configuration-type, @code{guix-configuration}}, for
28054 information about the @code{guix-configuration} data type. When the
28055 value is omitted, the default value specified by
28056 @code{guix-service-type} is used:
28059 (service guix-service-type)
28062 @code{guix-service-type} is quite simple because it extends other
28063 services but is not extensible itself.
28065 @c @subsubsubsection Extensible Service Types
28067 The service type for an @emph{extensible} service looks like this:
28070 (define udev-service-type
28071 (service-type (name 'udev)
28073 (list (service-extension shepherd-root-service-type
28074 udev-shepherd-service)))
28076 (compose concatenate) ;concatenate the list of rules
28077 (extend (lambda (config rules)
28079 (($ <udev-configuration> udev initial-rules)
28080 (udev-configuration
28081 (udev udev) ;the udev package to use
28082 (rules (append initial-rules rules)))))))))
28085 This is the service type for the
28086 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
28087 management daemon}. Compared to the previous example, in addition to an
28088 extension of @code{shepherd-root-service-type}, we see two new fields:
28092 This is the procedure to @dfn{compose} the list of extensions to
28093 services of this type.
28095 Services can extend the udev service by passing it lists of rules; we
28096 compose those extensions simply by concatenating them.
28099 This procedure defines how the value of the service is @dfn{extended} with
28100 the composition of the extensions.
28102 Udev extensions are composed into a list of rules, but the udev service
28103 value is itself a @code{<udev-configuration>} record. So here, we
28104 extend that record by appending the list of rules it contains to the
28105 list of contributed rules.
28108 This is a string giving an overview of the service type. The string can
28109 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
28110 @command{guix system search} command searches these strings and displays
28111 them (@pxref{Invoking guix system}).
28114 There can be only one instance of an extensible service type such as
28115 @code{udev-service-type}. If there were more, the
28116 @code{service-extension} specifications would be ambiguous.
28118 Still here? The next section provides a reference of the programming
28119 interface for services.
28121 @node Service Reference
28122 @subsection Service Reference
28124 We have seen an overview of service types (@pxref{Service Types and
28125 Services}). This section provides a reference on how to manipulate
28126 services and service types. This interface is provided by the
28127 @code{(gnu services)} module.
28129 @deffn {Scheme Procedure} service @var{type} [@var{value}]
28130 Return a new service of @var{type}, a @code{<service-type>} object (see
28131 below). @var{value} can be any object; it represents the parameters of
28132 this particular service instance.
28134 When @var{value} is omitted, the default value specified by @var{type}
28135 is used; if @var{type} does not specify a default value, an error is
28138 For instance, this:
28141 (service openssh-service-type)
28145 is equivalent to this:
28148 (service openssh-service-type
28149 (openssh-configuration))
28152 In both cases the result is an instance of @code{openssh-service-type}
28153 with the default configuration.
28156 @deffn {Scheme Procedure} service? @var{obj}
28157 Return true if @var{obj} is a service.
28160 @deffn {Scheme Procedure} service-kind @var{service}
28161 Return the type of @var{service}---i.e., a @code{<service-type>} object.
28164 @deffn {Scheme Procedure} service-value @var{service}
28165 Return the value associated with @var{service}. It represents its
28169 Here is an example of how a service is created and manipulated:
28173 (service nginx-service-type
28174 (nginx-configuration
28176 (log-directory log-directory)
28177 (run-directory run-directory)
28178 (file config-file))))
28183 (eq? (service-kind s) nginx-service-type)
28187 The @code{modify-services} form provides a handy way to change the
28188 parameters of some of the services of a list such as
28189 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
28190 evaluates to a list of services. Of course, you could always use
28191 standard list combinators such as @code{map} and @code{fold} to do that
28192 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
28193 @code{modify-services} simply provides a more concise form for this
28196 @deffn {Scheme Syntax} modify-services @var{services} @
28197 (@var{type} @var{variable} => @var{body}) @dots{}
28199 Modify the services listed in @var{services} according to the given
28200 clauses. Each clause has the form:
28203 (@var{type} @var{variable} => @var{body})
28206 where @var{type} is a service type---e.g.,
28207 @code{guix-service-type}---and @var{variable} is an identifier that is
28208 bound within the @var{body} to the service parameters---e.g., a
28209 @code{guix-configuration} instance---of the original service of that
28212 The @var{body} should evaluate to the new service parameters, which will
28213 be used to configure the new service. This new service will replace the
28214 original in the resulting list. Because a service's service parameters
28215 are created using @code{define-record-type*}, you can write a succinct
28216 @var{body} that evaluates to the new service parameters by using the
28217 @code{inherit} feature that @code{define-record-type*} provides.
28219 @xref{Using the Configuration System}, for example usage.
28223 Next comes the programming interface for service types. This is
28224 something you want to know when writing new service definitions, but not
28225 necessarily when simply looking for ways to customize your
28226 @code{operating-system} declaration.
28228 @deftp {Data Type} service-type
28229 @cindex service type
28230 This is the representation of a @dfn{service type} (@pxref{Service Types
28235 This is a symbol, used only to simplify inspection and debugging.
28237 @item @code{extensions}
28238 A non-empty list of @code{<service-extension>} objects (see below).
28240 @item @code{compose} (default: @code{#f})
28241 If this is @code{#f}, then the service type denotes services that cannot
28242 be extended---i.e., services that do not receive ``values'' from other
28245 Otherwise, it must be a one-argument procedure. The procedure is called
28246 by @code{fold-services} and is passed a list of values collected from
28247 extensions. It may return any single value.
28249 @item @code{extend} (default: @code{#f})
28250 If this is @code{#f}, services of this type cannot be extended.
28252 Otherwise, it must be a two-argument procedure: @code{fold-services}
28253 calls it, passing it the initial value of the service as the first
28254 argument and the result of applying @code{compose} to the extension
28255 values as the second argument. It must return a value that is a valid
28256 parameter value for the service instance.
28259 @xref{Service Types and Services}, for examples.
28262 @deffn {Scheme Procedure} service-extension @var{target-type} @
28264 Return a new extension for services of type @var{target-type}.
28265 @var{compute} must be a one-argument procedure: @code{fold-services}
28266 calls it, passing it the value associated with the service that provides
28267 the extension; it must return a valid value for the target service.
28270 @deffn {Scheme Procedure} service-extension? @var{obj}
28271 Return true if @var{obj} is a service extension.
28274 Occasionally, you might want to simply extend an existing service. This
28275 involves creating a new service type and specifying the extension of
28276 interest, which can be verbose; the @code{simple-service} procedure
28277 provides a shorthand for this.
28279 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
28280 Return a service that extends @var{target} with @var{value}. This works
28281 by creating a singleton service type @var{name}, of which the returned
28282 service is an instance.
28284 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
28288 (simple-service 'my-mcron-job mcron-service-type
28289 #~(job '(next-hour (3)) "guix gc -F 2G"))
28293 At the core of the service abstraction lies the @code{fold-services}
28294 procedure, which is responsible for ``compiling'' a list of services
28295 down to a single directory that contains everything needed to boot and
28296 run the system---the directory shown by the @command{guix system build}
28297 command (@pxref{Invoking guix system}). In essence, it propagates
28298 service extensions down the service graph, updating each node parameters
28299 on the way, until it reaches the root node.
28301 @deffn {Scheme Procedure} fold-services @var{services} @
28302 [#:target-type @var{system-service-type}]
28303 Fold @var{services} by propagating their extensions down to the root of
28304 type @var{target-type}; return the root service adjusted accordingly.
28307 Lastly, the @code{(gnu services)} module also defines several essential
28308 service types, some of which are listed below.
28310 @defvr {Scheme Variable} system-service-type
28311 This is the root of the service graph. It produces the system directory
28312 as returned by the @command{guix system build} command.
28315 @defvr {Scheme Variable} boot-service-type
28316 The type of the ``boot service'', which produces the @dfn{boot script}.
28317 The boot script is what the initial RAM disk runs when booting.
28320 @defvr {Scheme Variable} etc-service-type
28321 The type of the @file{/etc} service. This service is used to create
28322 files under @file{/etc} and can be extended by
28323 passing it name/file tuples such as:
28326 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
28329 In this example, the effect would be to add an @file{/etc/issue} file
28330 pointing to the given file.
28333 @defvr {Scheme Variable} setuid-program-service-type
28334 Type for the ``setuid-program service''. This service collects lists of
28335 executable file names, passed as gexps, and adds them to the set of
28336 setuid-root programs on the system (@pxref{Setuid Programs}).
28339 @defvr {Scheme Variable} profile-service-type
28340 Type of the service that populates the @dfn{system profile}---i.e., the
28341 programs under @file{/run/current-system/profile}. Other services can
28342 extend it by passing it lists of packages to add to the system profile.
28345 @cindex provenance tracking, of the operating system
28346 @defvr {Scheme Variable} provenance-service-type
28347 This is the type of the service that records @dfn{provenance meta-data}
28348 in the system itself. It creates several files under
28349 @file{/run/current-system}:
28353 This is a ``channel file'' that can be passed to @command{guix pull -C}
28354 or @command{guix time-machine -C}, and which describes the channels used
28355 to build the system, if that information was available
28356 (@pxref{Channels}).
28358 @item configuration.scm
28359 This is the file that was passed as the value for this
28360 @code{provenance-service-type} service. By default, @command{guix
28361 system reconfigure} automatically passes the OS configuration file it
28362 received on the command line.
28365 This contains the same information as the two other files but in a
28366 format that is more readily processable.
28369 In general, these two pieces of information (channels and configuration
28370 file) are enough to reproduce the operating system ``from source''.
28373 This information is necessary to rebuild your operating system, but it
28374 is not always sufficient. In particular, @file{configuration.scm}
28375 itself is insufficient if it is not self-contained---if it refers to
28376 external Guile modules or to extra files. If you want
28377 @file{configuration.scm} to be self-contained, we recommend that modules
28378 or files it refers to be part of a channel.
28380 Besides, provenance meta-data is ``silent'' in the sense that it does
28381 not change the bits contained in your system, @emph{except for the
28382 meta-data bits themselves}. Two different OS configurations or sets of
28383 channels can lead to the same system, bit-for-bit; when
28384 @code{provenance-service-type} is used, these two systems will have
28385 different meta-data and thus different store file names, which makes
28386 comparison less trivial.
28389 This service is automatically added to your operating system
28390 configuration when you use @command{guix system reconfigure},
28391 @command{guix system init}, or @command{guix deploy}.
28394 @node Shepherd Services
28395 @subsection Shepherd Services
28397 @cindex shepherd services
28399 @cindex init system
28400 The @code{(gnu services shepherd)} module provides a way to define
28401 services managed by the GNU@tie{}Shepherd, which is the
28402 initialization system---the first process that is started when the
28403 system boots, also known as PID@tie{}1
28404 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
28406 Services in the Shepherd can depend on each other. For instance, the
28407 SSH daemon may need to be started after the syslog daemon has been
28408 started, which in turn can only happen once all the file systems have
28409 been mounted. The simple operating system defined earlier (@pxref{Using
28410 the Configuration System}) results in a service graph like this:
28412 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
28414 You can actually generate such a graph for any operating system
28415 definition using the @command{guix system shepherd-graph} command
28416 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
28418 The @code{%shepherd-root-service} is a service object representing
28419 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
28420 by passing it lists of @code{<shepherd-service>} objects.
28422 @deftp {Data Type} shepherd-service
28423 The data type representing a service managed by the Shepherd.
28426 @item @code{provision}
28427 This is a list of symbols denoting what the service provides.
28429 These are the names that may be passed to @command{herd start},
28430 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
28431 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
28432 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
28434 @item @code{requirement} (default: @code{'()})
28435 List of symbols denoting the Shepherd services this one depends on.
28437 @cindex one-shot services, for the Shepherd
28438 @item @code{one-shot?} (default: @code{#f})
28439 Whether this service is @dfn{one-shot}. One-shot services stop immediately
28440 after their @code{start} action has completed. @xref{Slots of services,,,
28441 shepherd, The GNU Shepherd Manual}, for more info.
28443 @item @code{respawn?} (default: @code{#t})
28444 Whether to restart the service when it stops, for instance when the
28445 underlying process dies.
28448 @itemx @code{stop} (default: @code{#~(const #f)})
28449 The @code{start} and @code{stop} fields refer to the Shepherd's
28450 facilities to start and stop processes (@pxref{Service De- and
28451 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
28452 G-expressions that get expanded in the Shepherd configuration file
28453 (@pxref{G-Expressions}).
28455 @item @code{actions} (default: @code{'()})
28456 @cindex actions, of Shepherd services
28457 This is a list of @code{shepherd-action} objects (see below) defining
28458 @dfn{actions} supported by the service, in addition to the standard
28459 @code{start} and @code{stop} actions. Actions listed here become available as
28460 @command{herd} sub-commands:
28463 herd @var{action} @var{service} [@var{arguments}@dots{}]
28466 @item @code{auto-start?} (default: @code{#t})
28467 Whether this service should be started automatically by the Shepherd. If it
28468 is @code{#f} the service has to be started manually with @code{herd start}.
28470 @item @code{documentation}
28471 A documentation string, as shown when running:
28474 herd doc @var{service-name}
28477 where @var{service-name} is one of the symbols in @code{provision}
28478 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
28480 @item @code{modules} (default: @code{%default-modules})
28481 This is the list of modules that must be in scope when @code{start} and
28482 @code{stop} are evaluated.
28487 @deftp {Data Type} shepherd-action
28488 This is the data type that defines additional actions implemented by a
28489 Shepherd service (see above).
28493 Symbol naming the action.
28495 @item documentation
28496 This is a documentation string for the action. It can be viewed by running:
28499 herd doc @var{service} action @var{action}
28503 This should be a gexp that evaluates to a procedure of at least one argument,
28504 which is the ``running value'' of the service (@pxref{Slots of services,,,
28505 shepherd, The GNU Shepherd Manual}).
28508 The following example defines an action called @code{say-hello} that kindly
28514 (documentation "Say hi!")
28515 (procedure #~(lambda (running . args)
28516 (format #t "Hello, friend! arguments: ~s\n"
28521 Assuming this action is added to the @code{example} service, then you can do:
28524 # herd say-hello example
28525 Hello, friend! arguments: ()
28526 # herd say-hello example a b c
28527 Hello, friend! arguments: ("a" "b" "c")
28530 This, as you can see, is a fairly sophisticated way to say hello.
28531 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
28535 @defvr {Scheme Variable} shepherd-root-service-type
28536 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
28538 This is the service type that extensions target when they want to create
28539 shepherd services (@pxref{Service Types and Services}, for an example).
28540 Each extension must pass a list of @code{<shepherd-service>}.
28543 @defvr {Scheme Variable} %shepherd-root-service
28544 This service represents PID@tie{}1.
28548 @node Documentation
28549 @chapter Documentation
28551 @cindex documentation, searching for
28552 @cindex searching for documentation
28553 @cindex Info, documentation format
28555 @cindex manual pages
28556 In most cases packages installed with Guix come with documentation.
28557 There are two main documentation formats: ``Info'', a browseable
28558 hypertext format used for GNU software, and ``manual pages'' (or ``man
28559 pages''), the linear documentation format traditionally found on Unix.
28560 Info manuals are accessed with the @command{info} command or with Emacs,
28561 and man pages are accessed using @command{man}.
28563 You can look for documentation of software installed on your system by
28564 keyword. For example, the following command searches for information
28565 about ``TLS'' in Info manuals:
28569 "(emacs)Network Security" -- STARTTLS
28570 "(emacs)Network Security" -- TLS
28571 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
28572 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
28577 The command below searches for the same keyword in man pages:
28581 SSL (7) - OpenSSL SSL/TLS library
28582 certtool (1) - GnuTLS certificate tool
28586 These searches are purely local to your computer so you have the
28587 guarantee that documentation you find corresponds to what you have
28588 actually installed, you can access it off-line, and your privacy is
28591 Once you have these results, you can view the relevant documentation by
28595 $ info "(gnutls)Core TLS API"
28605 Info manuals contain sections and indices as well as hyperlinks like
28606 those found in Web pages. The @command{info} reader (@pxref{Top, Info
28607 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
28608 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
28609 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
28610 Introduction}, for an introduction to Info navigation.
28612 @node Installing Debugging Files
28613 @chapter Installing Debugging Files
28615 @cindex debugging files
28616 Program binaries, as produced by the GCC compilers for instance, are
28617 typically written in the ELF format, with a section containing
28618 @dfn{debugging information}. Debugging information is what allows the
28619 debugger, GDB, to map binary code to source code; it is required to
28620 debug a compiled program in good conditions.
28622 The problem with debugging information is that is takes up a fair amount
28623 of disk space. For example, debugging information for the GNU C Library
28624 weighs in at more than 60 MiB. Thus, as a user, keeping all the
28625 debugging info of all the installed programs is usually not an option.
28626 Yet, space savings should not come at the cost of an impediment to
28627 debugging---especially in the GNU system, which should make it easier
28628 for users to exert their computing freedom (@pxref{GNU Distribution}).
28630 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
28631 mechanism that allows users to get the best of both worlds: debugging
28632 information can be stripped from the binaries and stored in separate
28633 files. GDB is then able to load debugging information from those files,
28634 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
28637 The GNU distribution takes advantage of this by storing debugging
28638 information in the @code{lib/debug} sub-directory of a separate package
28639 output unimaginatively called @code{debug} (@pxref{Packages with
28640 Multiple Outputs}). Users can choose to install the @code{debug} output
28641 of a package when they need it. For instance, the following command
28642 installs the debugging information for the GNU C Library and for GNU
28646 guix install glibc:debug guile:debug
28649 GDB must then be told to look for debug files in the user's profile, by
28650 setting the @code{debug-file-directory} variable (consider setting it
28651 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
28655 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
28658 From there on, GDB will pick up debugging information from the
28659 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
28661 In addition, you will most likely want GDB to be able to show the source
28662 code being debugged. To do that, you will have to unpack the source
28663 code of the package of interest (obtained with @code{guix build
28664 --source}, @pxref{Invoking guix build}), and to point GDB to that source
28665 directory using the @code{directory} command (@pxref{Source Path,
28666 @code{directory},, gdb, Debugging with GDB}).
28668 @c XXX: keep me up-to-date
28669 The @code{debug} output mechanism in Guix is implemented by the
28670 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
28671 opt-in---debugging information is available only for the packages
28672 with definitions explicitly declaring a @code{debug} output. This may be
28673 changed to opt-out in the future if our build farm servers can handle
28674 the load. To check whether a package has a @code{debug} output, use
28675 @command{guix package --list-available} (@pxref{Invoking guix package}).
28678 @node Security Updates
28679 @chapter Security Updates
28681 @cindex security updates
28682 @cindex security vulnerabilities
28683 Occasionally, important security vulnerabilities are discovered in software
28684 packages and must be patched. Guix developers try hard to keep track of
28685 known vulnerabilities and to apply fixes as soon as possible in the
28686 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
28687 containing only security updates). The @command{guix lint} tool helps
28688 developers find out about vulnerable versions of software packages in the
28693 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
28694 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
28695 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
28699 @xref{Invoking guix lint}, for more information.
28701 Guix follows a functional
28702 package management discipline (@pxref{Introduction}), which implies
28703 that, when a package is changed, @emph{every package that depends on it}
28704 must be rebuilt. This can significantly slow down the deployment of
28705 fixes in core packages such as libc or Bash, since basically the whole
28706 distribution would need to be rebuilt. Using pre-built binaries helps
28707 (@pxref{Substitutes}), but deployment may still take more time than
28711 To address this, Guix implements @dfn{grafts}, a mechanism that allows
28712 for fast deployment of critical updates without the costs associated
28713 with a whole-distribution rebuild. The idea is to rebuild only the
28714 package that needs to be patched, and then to ``graft'' it onto packages
28715 explicitly installed by the user and that were previously referring to
28716 the original package. The cost of grafting is typically very low, and
28717 order of magnitudes lower than a full rebuild of the dependency chain.
28719 @cindex replacements of packages, for grafts
28720 For instance, suppose a security update needs to be applied to Bash.
28721 Guix developers will provide a package definition for the ``fixed''
28722 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
28723 Packages}). Then, the original package definition is augmented with a
28724 @code{replacement} field pointing to the package containing the bug fix:
28731 (replacement bash-fixed)))
28734 From there on, any package depending directly or indirectly on Bash---as
28735 reported by @command{guix gc --requisites} (@pxref{Invoking guix
28736 gc})---that is installed is automatically ``rewritten'' to refer to
28737 @code{bash-fixed} instead of @code{bash}. This grafting process takes
28738 time proportional to the size of the package, usually less than a
28739 minute for an ``average'' package on a recent machine. Grafting is
28740 recursive: when an indirect dependency requires grafting, then grafting
28741 ``propagates'' up to the package that the user is installing.
28743 Currently, the length of the name and version of the graft and that of
28744 the package it replaces (@code{bash-fixed} and @code{bash} in the example
28745 above) must be equal. This restriction mostly comes from the fact that
28746 grafting works by patching files, including binary files, directly.
28747 Other restrictions may apply: for instance, when adding a graft to a
28748 package providing a shared library, the original shared library and its
28749 replacement must have the same @code{SONAME} and be binary-compatible.
28751 The @option{--no-grafts} command-line option allows you to forcefully
28752 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
28756 guix build bash --no-grafts
28760 returns the store file name of the original Bash, whereas:
28767 returns the store file name of the ``fixed'', replacement Bash. This
28768 allows you to distinguish between the two variants of Bash.
28770 To verify which Bash your whole profile refers to, you can run
28771 (@pxref{Invoking guix gc}):
28774 guix gc -R `readlink -f ~/.guix-profile` | grep bash
28778 @dots{} and compare the store file names that you get with those above.
28779 Likewise for a complete Guix system generation:
28782 guix gc -R `guix system build my-config.scm` | grep bash
28785 Lastly, to check which Bash running processes are using, you can use the
28786 @command{lsof} command:
28789 lsof | grep /gnu/store/.*bash
28793 @node Bootstrapping
28794 @chapter Bootstrapping
28796 @c Adapted from the ELS 2013 paper.
28798 @cindex bootstrapping
28800 Bootstrapping in our context refers to how the distribution gets built
28801 ``from nothing''. Remember that the build environment of a derivation
28802 contains nothing but its declared inputs (@pxref{Introduction}). So
28803 there's an obvious chicken-and-egg problem: how does the first package
28804 get built? How does the first compiler get compiled? Note that this is
28805 a question of interest only to the curious hacker, not to the regular
28806 user, so you can shamelessly skip this section if you consider yourself
28807 a ``regular user''.
28809 @cindex bootstrap binaries
28810 The GNU system is primarily made of C code, with libc at its core. The
28811 GNU build system itself assumes the availability of a Bourne shell and
28812 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
28813 `grep'. Furthermore, build programs---programs that run
28814 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
28815 (@pxref{Derivations}). Consequently, to be able to build anything at
28816 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
28817 Binutils, libc, and the other packages mentioned above---the
28818 @dfn{bootstrap binaries}.
28820 These bootstrap binaries are ``taken for granted'', though we can also
28821 re-create them if needed (@pxref{Preparing to Use the Bootstrap
28825 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
28826 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
28829 @node Reduced Binary Seed Bootstrap
28830 @section The Reduced Binary Seed Bootstrap
28832 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
28833 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
28834 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
28835 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
28836 ``taken for granted.''
28838 Taking the bootstrap binaries for granted means that we consider them to
28839 be a correct and trustworthy ``seed'' for building the complete system.
28840 Therein lies a problem: the combined size of these bootstrap binaries is
28841 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
28842 or even inspecting these is next to impossible.
28844 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
28845 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
28846 Source Bootstrap'' and while we are working towards that goal it would
28847 be hyperbole to use that term for what we do now.}.
28849 The Reduced Binary Seed bootstrap removes the most critical tools---from a
28850 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
28851 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
28852 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
28853 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
28855 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
28856 C Library are built from source. From here on the more traditional
28857 bootstrap process resumes. This approach has reduced the bootstrap
28858 binaries in size to about 145MB in Guix v1.1.
28860 The next step that Guix has taken is to replace the shell and all its
28861 utilities with implementations in Guile Scheme, the @emph{Scheme-only
28862 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
28863 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
28864 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
28865 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
28866 removed are now built from source.
28868 Building the GNU System from source is currently only possibly by adding
28869 some historical GNU packages as intermediate steps@footnote{Packages
28870 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
28871 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
28872 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
28873 and GNU packages become more bootstrappable again (e.g., new releases of
28874 GNU Sed will also ship as gzipped tarballs again, as alternative to the
28875 hard to bootstrap @code{xz}-compression), this set of added packages can
28876 hopefully be reduced again.
28878 The graph below shows the resulting dependency graph for
28879 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
28880 traditional bootstrap of the rest of the Guix System.
28882 @c ./pre-inst-env guix graph -e '(@@ (gnu packages commencement) gcc-core-mesboot0)' | sed -re 's,((bootstrap-mescc-tools|bootstrap-mes|guile-bootstrap).*shape =) box,\1 ellipse,' > doc/images/gcc-core-mesboot0-graph.dot
28883 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
28885 The only significant binary bootstrap seeds that remain@footnote{
28886 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
28887 together with @code{mes}.} are a Scheme intepreter and a Scheme
28888 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
28889 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
28890 to get Guile running.}.
28892 This further reduction has brought down the size of the binary seed to
28893 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
28895 Work is ongoing to remove all binary blobs from our free software
28896 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
28897 is work to bring these bootstraps to the @code{arm-linux} and
28898 @code{aarch64-linux} architectures and to the Hurd.
28900 If you are interested, join us on @samp{#bootstrappable} on the Freenode
28901 IRC network or discuss on @email{bug-mes@@gnu.org} or
28902 @email{gash-devel@@nongnu.org}.
28904 @node Preparing to Use the Bootstrap Binaries
28905 @section Preparing to Use the Bootstrap Binaries
28907 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
28908 @c large image, it's hard to scroll. Oh well.
28909 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
28911 The figure above shows the very beginning of the dependency graph of the
28912 distribution, corresponding to the package definitions of the @code{(gnu
28913 packages bootstrap)} module. A similar figure can be generated with
28914 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
28917 guix graph -t derivation \
28918 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
28919 | dot -Tps > gcc.ps
28922 or, for the further Reduced Binary Seed bootstrap
28925 guix graph -t derivation \
28926 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
28927 | dot -Tps > mes.ps
28930 At this level of detail, things are
28931 slightly complex. First, Guile itself consists of an ELF executable,
28932 along with many source and compiled Scheme files that are dynamically
28933 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
28934 tarball shown in this graph. This tarball is part of Guix's ``source''
28935 distribution, and gets inserted into the store with @code{add-to-store}
28936 (@pxref{The Store}).
28938 But how do we write a derivation that unpacks this tarball and adds it
28939 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
28940 derivation---the first one that gets built---uses @code{bash} as its
28941 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
28942 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
28943 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
28944 the Guix source distribution, whose sole purpose is to allow the Guile
28945 tarball to be unpacked.
28947 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
28948 Guile that can be used to run subsequent build programs. Its first task
28949 is to download tarballs containing the other pre-built binaries---this
28950 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
28951 @code{ftp-client.scm} are used for this purpose. The
28952 @code{module-import.drv} derivations import those modules in a directory
28953 in the store, using the original layout. The
28954 @code{module-import-compiled.drv} derivations compile those modules, and
28955 write them in an output directory with the right layout. This
28956 corresponds to the @code{#:modules} argument of
28957 @code{build-expression->derivation} (@pxref{Derivations}).
28959 Finally, the various tarballs are unpacked by the derivations
28960 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
28961 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
28962 point we have a working C tool chain.
28964 @unnumberedsec Building the Build Tools
28966 Bootstrapping is complete when we have a full tool chain that does not
28967 depend on the pre-built bootstrap tools discussed above. This
28968 no-dependency requirement is verified by checking whether the files of
28969 the final tool chain contain references to the @file{/gnu/store}
28970 directories of the bootstrap inputs. The process that leads to this
28971 ``final'' tool chain is described by the package definitions found in
28972 the @code{(gnu packages commencement)} module.
28974 The @command{guix graph} command allows us to ``zoom out'' compared to
28975 the graph above, by looking at the level of package objects instead of
28976 individual derivations---remember that a package may translate to
28977 several derivations, typically one derivation to download its source,
28978 one to build the Guile modules it needs, and one to actually build the
28979 package from source. The command:
28982 guix graph -t bag \
28983 -e '(@@@@ (gnu packages commencement)
28984 glibc-final-with-bootstrap-bash)' | xdot -
28988 displays the dependency graph leading to the ``final'' C
28989 library@footnote{You may notice the @code{glibc-intermediate} label,
28990 suggesting that it is not @emph{quite} final, but as a good
28991 approximation, we will consider it final.}, depicted below.
28993 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
28995 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
28996 The first tool that gets built with the bootstrap binaries is
28997 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
28998 for all the following packages. From there Findutils and Diffutils get
29001 Then come the first-stage Binutils and GCC, built as pseudo cross
29002 tools---i.e., with @option{--target} equal to @option{--host}. They are
29003 used to build libc. Thanks to this cross-build trick, this libc is
29004 guaranteed not to hold any reference to the initial tool chain.
29006 From there the final Binutils and GCC (not shown above) are built. GCC
29007 uses @command{ld} from the final Binutils, and links programs against
29008 the just-built libc. This tool chain is used to build the other
29009 packages used by Guix and by the GNU Build System: Guile, Bash,
29012 And voilà! At this point we have the complete set of build tools that
29013 the GNU Build System expects. These are in the @code{%final-inputs}
29014 variable of the @code{(gnu packages commencement)} module, and are
29015 implicitly used by any package that uses @code{gnu-build-system}
29016 (@pxref{Build Systems, @code{gnu-build-system}}).
29019 @unnumberedsec Building the Bootstrap Binaries
29021 @cindex bootstrap binaries
29022 Because the final tool chain does not depend on the bootstrap binaries,
29023 those rarely need to be updated. Nevertheless, it is useful to have an
29024 automated way to produce them, should an update occur, and this is what
29025 the @code{(gnu packages make-bootstrap)} module provides.
29027 The following command builds the tarballs containing the bootstrap binaries
29028 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
29029 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
29030 and Guile, and a tarball containing a mixture of Coreutils and other basic
29031 command-line tools):
29034 guix build bootstrap-tarballs
29037 The generated tarballs are those that should be referred to in the
29038 @code{(gnu packages bootstrap)} module mentioned at the beginning of
29041 Still here? Then perhaps by now you've started to wonder: when do we
29042 reach a fixed point? That is an interesting question! The answer is
29043 unknown, but if you would like to investigate further (and have
29044 significant computational and storage resources to do so), then let us
29047 @unnumberedsec Reducing the Set of Bootstrap Binaries
29049 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
29050 binary code! Why is that a problem? It's a problem because these big chunks
29051 of binary code are practically non-auditable, which makes it hard to establish
29052 what source code produced them. Every unauditable binary also leaves us
29053 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
29054 paper @emph{Reflections on Trusting Trust}.
29056 This is mitigated by the fact that our bootstrap binaries were generated
29057 from an earlier Guix revision. Nevertheless it lacks the level of
29058 transparency that we get in the rest of the package dependency graph,
29059 where Guix always gives us a source-to-binary mapping. Thus, our goal
29060 is to reduce the set of bootstrap binaries to the bare minimum.
29062 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
29063 on-going projects to do that. One of these is about replacing the
29064 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
29065 of increasing complexity, which could be built from source starting from
29066 a simple and auditable assembler.
29068 Our first major achievement is the replacement of of GCC, the GNU C Library
29069 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
29070 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
29071 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
29072 bootstrapped yet and thus we inject them as binary seeds. We call this the
29073 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
29074 binaries! Also, it has eliminated the C compiler binary; i686-linux and
29075 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
29077 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
29078 also looking at any other bootstrap binaries. Your help is welcome!
29081 @chapter Porting to a New Platform
29083 As discussed above, the GNU distribution is self-contained, and
29084 self-containment is achieved by relying on pre-built ``bootstrap
29085 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
29086 operating system kernel, CPU architecture, and application binary
29087 interface (ABI). Thus, to port the distribution to a platform that is
29088 not yet supported, one must build those bootstrap binaries, and update
29089 the @code{(gnu packages bootstrap)} module to use them on that platform.
29091 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
29092 When everything goes well, and assuming the GNU tool chain supports the
29093 target platform, this can be as simple as running a command like this
29097 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
29100 For this to work, the @code{glibc-dynamic-linker} procedure in
29101 @code{(gnu packages bootstrap)} must be augmented to return the right
29102 file name for libc's dynamic linker on that platform; likewise,
29103 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
29104 taught about the new platform.
29106 Once these are built, the @code{(gnu packages bootstrap)} module needs
29107 to be updated to refer to these binaries on the target platform. That
29108 is, the hashes and URLs of the bootstrap tarballs for the new platform
29109 must be added alongside those of the currently supported platforms. The
29110 bootstrap Guile tarball is treated specially: it is expected to be
29111 available locally, and @file{gnu/local.mk} has rules to download it for
29112 the supported architectures; a rule for the new platform must be added
29115 In practice, there may be some complications. First, it may be that the
29116 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
29117 above) is not recognized by all the GNU tools. Typically, glibc
29118 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
29119 configure flag (see @code{gcc.scm} for examples of how to handle this).
29120 Second, some of the required packages could fail to build for that
29121 platform. Lastly, the generated binaries could be broken for some
29124 @c *********************************************************************
29125 @include contributing.texi
29127 @c *********************************************************************
29128 @node Acknowledgments
29129 @chapter Acknowledgments
29131 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
29132 which was designed and
29133 implemented by Eelco Dolstra, with contributions from other people (see
29134 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
29135 management, and promoted unprecedented features, such as transactional
29136 package upgrades and rollbacks, per-user profiles, and referentially
29137 transparent build processes. Without this work, Guix would not exist.
29139 The Nix-based software distributions, Nixpkgs and NixOS, have also been
29140 an inspiration for Guix.
29142 GNU@tie{}Guix itself is a collective work with contributions from a
29143 number of people. See the @file{AUTHORS} file in Guix for more
29144 information on these fine people. The @file{THANKS} file lists people
29145 who have helped by reporting bugs, taking care of the infrastructure,
29146 providing artwork and themes, making suggestions, and more---thank you!
29149 @c *********************************************************************
29150 @node GNU Free Documentation License
29151 @appendix GNU Free Documentation License
29152 @cindex license, GNU Free Documentation License
29153 @include fdl-1.3.texi
29155 @c *********************************************************************
29156 @node Concept Index
29157 @unnumbered Concept Index
29160 @node Programming Index
29161 @unnumbered Programming Index
29162 @syncodeindex tp fn
29163 @syncodeindex vr fn
29168 @c Local Variables:
29169 @c ispell-local-dictionary: "american";