6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
14 @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=15145
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER ci.guix.gnu.org
21 @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
24 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès@*
25 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
26 Copyright @copyright{} 2013 Nikita Karetnikov@*
27 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
28 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
29 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
30 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
31 Copyright @copyright{} 2015, 2016, 2017, 2019 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 ng0@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017 Christopher Allan Webber@*
49 Copyright @copyright{} 2017, 2018 Marius Bakke@*
50 Copyright @copyright{} 2017 Hartmut Goebel@*
51 Copyright @copyright{} 2017, 2019 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018, 2019 Tobias Geerinckx-Rice@*
53 Copyright @copyright{} 2017 George Clemmer@*
54 Copyright @copyright{} 2017 Andy Wingo@*
55 Copyright @copyright{} 2017, 2018, 2019 Arun Isaac@*
56 Copyright @copyright{} 2017 nee@*
57 Copyright @copyright{} 2018 Rutger Helling@*
58 Copyright @copyright{} 2018 Oleg Pykhalov@*
59 Copyright @copyright{} 2018 Mike Gerwitz@*
60 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
61 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
62 Copyright @copyright{} 2018, 2019 Florian Pelz@*
63 Copyright @copyright{} 2018 Laura Lazzati@*
64 Copyright @copyright{} 2018 Alex Vong@*
65 Copyright @copyright{} 2019 Josh Holland@*
66 Copyright @copyright{} 2019 Diego Nicola Barbato@*
67 Copyright @copyright{} 2019 Ivan Petkov@*
68 Copyright @copyright{} 2019 Jakob L. Kreuze@*
70 Permission is granted to copy, distribute and/or modify this document
71 under the terms of the GNU Free Documentation License, Version 1.3 or
72 any later version published by the Free Software Foundation; with no
73 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
74 copy of the license is included in the section entitled ``GNU Free
75 Documentation License''.
78 @dircategory System administration
80 * Guix: (guix). Manage installed software and system configuration.
81 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
82 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
83 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
84 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
85 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
88 @dircategory Software development
90 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
91 * guix build: (guix)Invoking guix build. Building packages.
92 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
96 @title GNU Guix Reference Manual
97 @subtitle Using the GNU Guix Functional Package Manager
98 @author The GNU Guix Developers
101 @vskip 0pt plus 1filll
102 Edition @value{EDITION} @*
110 @c *********************************************************************
114 This document describes GNU Guix version @value{VERSION}, a functional
115 package management tool written for the GNU system.
117 @c TRANSLATORS: You can replace the following paragraph with information on
118 @c how to join your own translation team and how to report issues with the
120 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
121 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
122 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
123 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
124 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
125 would like to translate it in your native language, consider joining the
126 @uref{https://translationproject.org/domain/guix-manual.html, Translation
130 * Introduction:: What is Guix about?
131 * Installation:: Installing Guix.
132 * System Installation:: Installing the whole operating system.
133 * Package Management:: Package installation, upgrade, etc.
134 * Development:: Guix-aided software development.
135 * Programming Interface:: Using Guix in Scheme.
136 * Utilities:: Package management commands.
137 * System Configuration:: Configuring the operating system.
138 * Documentation:: Browsing software user manuals.
139 * Installing Debugging Files:: Feeding the debugger.
140 * Security Updates:: Deploying security fixes quickly.
141 * Bootstrapping:: GNU/Linux built from scratch.
142 * Porting:: Targeting another platform or kernel.
143 * Contributing:: Your help needed!
145 * Acknowledgments:: Thanks!
146 * GNU Free Documentation License:: The license of this manual.
147 * Concept Index:: Concepts.
148 * Programming Index:: Data types, functions, and variables.
151 --- The Detailed Node Listing ---
155 * Managing Software the Guix Way:: What's special.
156 * GNU Distribution:: The packages and tools.
160 * Binary Installation:: Getting Guix running in no time!
161 * Requirements:: Software needed to build and run Guix.
162 * Running the Test Suite:: Testing Guix.
163 * Setting Up the Daemon:: Preparing the build daemon's environment.
164 * Invoking guix-daemon:: Running the build daemon.
165 * Application Setup:: Application-specific setup.
167 Setting Up the Daemon
169 * Build Environment Setup:: Preparing the isolated build environment.
170 * Daemon Offload Setup:: Offloading builds to remote machines.
171 * SELinux Support:: Using an SELinux policy for the daemon.
175 * Limitations:: What you can expect.
176 * Hardware Considerations:: Supported hardware.
177 * USB Stick and DVD Installation:: Preparing the installation medium.
178 * Preparing for Installation:: Networking, partitioning, etc.
179 * Guided Graphical Installation:: Easy graphical installation.
180 * Manual Installation:: Manual installation for wizards.
181 * After System Installation:: When installation succeeded.
182 * Installing Guix in a VM:: Guix System playground.
183 * Building the Installation Image:: How this comes to be.
187 * Keyboard Layout and Networking and Partitioning:: Initial setup.
188 * Proceeding with the Installation:: Installing.
192 * Features:: How Guix will make your life brighter.
193 * Invoking guix package:: Package installation, removal, etc.
194 * Substitutes:: Downloading pre-built binaries.
195 * Packages with Multiple Outputs:: Single source package, multiple outputs.
196 * Invoking guix gc:: Running the garbage collector.
197 * Invoking guix pull:: Fetching the latest Guix and distribution.
198 * Channels:: Customizing the package collection.
199 * Inferiors:: Interacting with another revision of Guix.
200 * Invoking guix describe:: Display information about your Guix revision.
201 * Invoking guix archive:: Exporting and importing store files.
205 * Official Substitute Server:: One particular source of substitutes.
206 * Substitute Server Authorization:: How to enable or disable substitutes.
207 * Substitute Authentication:: How Guix verifies substitutes.
208 * Proxy Settings:: How to get substitutes via proxy.
209 * Substitution Failure:: What happens when substitution fails.
210 * On Trusting Binaries:: How can you trust that binary blob?
214 * Invoking guix environment:: Setting up development environments.
215 * Invoking guix pack:: Creating software bundles.
217 Programming Interface
219 * Package Modules:: Packages from the programmer's viewpoint.
220 * Defining Packages:: Defining new packages.
221 * Build Systems:: Specifying how packages are built.
222 * The Store:: Manipulating the package store.
223 * Derivations:: Low-level interface to package derivations.
224 * The Store Monad:: Purely functional interface to the store.
225 * G-Expressions:: Manipulating build expressions.
226 * Invoking guix repl:: Fiddling with Guix interactively.
230 * package Reference:: The package data type.
231 * origin Reference:: The origin data type.
235 * Invoking guix build:: Building packages from the command line.
236 * Invoking guix edit:: Editing package definitions.
237 * Invoking guix download:: Downloading a file and printing its hash.
238 * Invoking guix hash:: Computing the cryptographic hash of a file.
239 * Invoking guix import:: Importing package definitions.
240 * Invoking guix refresh:: Updating package definitions.
241 * Invoking guix lint:: Finding errors in package definitions.
242 * Invoking guix size:: Profiling disk usage.
243 * Invoking guix graph:: Visualizing the graph of packages.
244 * Invoking guix publish:: Sharing substitutes.
245 * Invoking guix challenge:: Challenging substitute servers.
246 * Invoking guix copy:: Copying to and from a remote store.
247 * Invoking guix container:: Process isolation.
248 * Invoking guix weather:: Assessing substitute availability.
249 * Invoking guix processes:: Listing client processes.
251 Invoking @command{guix build}
253 * Common Build Options:: Build options for most commands.
254 * Package Transformation Options:: Creating variants of packages.
255 * Additional Build Options:: Options specific to 'guix build'.
256 * Debugging Build Failures:: Real life packaging experience.
260 * Using the Configuration System:: Customizing your GNU system.
261 * operating-system Reference:: Detail of operating-system declarations.
262 * File Systems:: Configuring file system mounts.
263 * Mapped Devices:: Block device extra processing.
264 * User Accounts:: Specifying user accounts.
265 * Keyboard Layout:: How the system interprets key strokes.
266 * Locales:: Language and cultural convention settings.
267 * Services:: Specifying system services.
268 * Setuid Programs:: Programs running with root privileges.
269 * X.509 Certificates:: Authenticating HTTPS servers.
270 * Name Service Switch:: Configuring libc's name service switch.
271 * Initial RAM Disk:: Linux-Libre bootstrapping.
272 * Bootloader Configuration:: Configuring the boot loader.
273 * Invoking guix system:: Instantiating a system configuration.
274 * Invoking guix deploy:: Deploying a system configuration to a remote host.
275 * Running Guix in a VM:: How to run Guix System in a virtual machine.
276 * Defining Services:: Adding new service definitions.
280 * Base Services:: Essential system services.
281 * Scheduled Job Execution:: The mcron service.
282 * Log Rotation:: The rottlog service.
283 * Networking Services:: Network setup, SSH daemon, etc.
284 * X Window:: Graphical display.
285 * Printing Services:: Local and remote printer support.
286 * Desktop Services:: D-Bus and desktop services.
287 * Sound Services:: ALSA and Pulseaudio services.
288 * Database Services:: SQL databases, key-value stores, etc.
289 * Mail Services:: IMAP, POP3, SMTP, and all that.
290 * Messaging Services:: Messaging services.
291 * Telephony Services:: Telephony services.
292 * Monitoring Services:: Monitoring services.
293 * Kerberos Services:: Kerberos services.
294 * Web Services:: Web servers.
295 * Certificate Services:: TLS certificates via Let's Encrypt.
296 * DNS Services:: DNS daemons.
297 * VPN Services:: VPN daemons.
298 * Network File System:: NFS related services.
299 * Continuous Integration:: The Cuirass service.
300 * Power Management Services:: Extending battery life.
301 * Audio Services:: The MPD.
302 * Virtualization Services:: Virtualization services.
303 * Version Control Services:: Providing remote access to Git repositories.
304 * Game Services:: Game servers.
305 * Miscellaneous Services:: Other services.
309 * Service Composition:: The model for composing services.
310 * Service Types and Services:: Types and services.
311 * Service Reference:: API reference.
312 * Shepherd Services:: A particular type of service.
317 @c *********************************************************************
319 @chapter Introduction
322 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
323 using the international phonetic alphabet (IPA).} is a package
324 management tool for and distribution of the GNU system.
325 Guix makes it easy for unprivileged
326 users to install, upgrade, or remove software packages, to roll back to a
327 previous package set, to build packages from source, and generally
328 assists with the creation and maintenance of software environments.
331 @cindex GuixSD, now Guix System
332 @cindex Guix System Distribution, now Guix System
333 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
334 complements the available tools without interference (@pxref{Installation}),
335 or you can use it as a standalone operating system distribution,
336 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
337 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
338 group everything under the ``Guix'' banner since, after all, Guix System is
339 readily available through the @command{guix system} command, even if you're
340 using a different distro underneath!}. @xref{GNU Distribution}.
343 * Managing Software the Guix Way:: What's special.
344 * GNU Distribution:: The packages and tools.
347 @node Managing Software the Guix Way
348 @section Managing Software the Guix Way
350 @cindex user interfaces
351 Guix provides a command-line package management interface
352 (@pxref{Package Management}), tools to help with software development
353 (@pxref{Development}), command-line utilities for more advanced usage,
354 (@pxref{Utilities}), as well as Scheme programming interfaces
355 (@pxref{Programming Interface}).
357 Its @dfn{build daemon} is responsible for building packages on behalf of
358 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
359 binaries from authorized sources (@pxref{Substitutes}).
361 @cindex extensibility of the distribution
362 @cindex customization, of packages
363 Guix includes package definitions for many GNU and non-GNU packages, all
364 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
365 user's computing freedom}. It is @emph{extensible}: users can write
366 their own package definitions (@pxref{Defining Packages}) and make them
367 available as independent package modules (@pxref{Package Modules}). It
368 is also @emph{customizable}: users can @emph{derive} specialized package
369 definitions from existing ones, including from the command line
370 (@pxref{Package Transformation Options}).
372 @cindex functional package management
374 Under the hood, Guix implements the @dfn{functional package management}
375 discipline pioneered by Nix (@pxref{Acknowledgments}).
376 In Guix, the package build and installation process is seen
377 as a @emph{function}, in the mathematical sense. That function takes inputs,
378 such as build scripts, a compiler, and libraries, and
379 returns an installed package. As a pure function, its result depends
380 solely on its inputs---for instance, it cannot refer to software or
381 scripts that were not explicitly passed as inputs. A build function
382 always produces the same result when passed a given set of inputs. It
383 cannot alter the environment of the running system in
384 any way; for instance, it cannot create, modify, or delete files outside
385 of its build and installation directories. This is achieved by running
386 build processes in isolated environments (or @dfn{containers}), where only their
387 explicit inputs are visible.
390 The result of package build functions is @dfn{cached} in the file
391 system, in a special directory called @dfn{the store} (@pxref{The
392 Store}). Each package is installed in a directory of its own in the
393 store---by default under @file{/gnu/store}. The directory name contains
394 a hash of all the inputs used to build that package; thus, changing an
395 input yields a different directory name.
397 This approach is the foundation for the salient features of Guix: support
398 for transactional package upgrade and rollback, per-user installation, and
399 garbage collection of packages (@pxref{Features}).
402 @node GNU Distribution
403 @section GNU Distribution
406 Guix comes with a distribution of the GNU system consisting entirely of
407 free software@footnote{The term ``free'' here refers to the
408 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
409 users of that software}.}. The
410 distribution can be installed on its own (@pxref{System Installation}),
411 but it is also possible to install Guix as a package manager on top of
412 an installed GNU/Linux system (@pxref{Installation}). When we need to
413 distinguish between the two, we refer to the standalone distribution as
416 The distribution provides core GNU packages such as GNU libc, GCC, and
417 Binutils, as well as many GNU and non-GNU applications. The complete
418 list of available packages can be browsed
419 @url{https://www.gnu.org/software/guix/packages,on-line} or by
420 running @command{guix package} (@pxref{Invoking guix package}):
423 guix package --list-available
426 Our goal is to provide a practical 100% free software distribution of
427 Linux-based and other variants of GNU, with a focus on the promotion and
428 tight integration of GNU components, and an emphasis on programs and
429 tools that help users exert that freedom.
431 Packages are currently available on the following platforms:
436 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
439 Intel 32-bit architecture (IA32), Linux-Libre kernel;
442 ARMv7-A architecture with hard float, Thumb-2 and NEON,
443 using the EABI hard-float application binary interface (ABI),
444 and Linux-Libre kernel.
447 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
450 little-endian 64-bit MIPS processors, specifically the Loongson series,
451 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
452 supported; in particular, the project's build farms no longer provide
453 substitutes for this architecture.
457 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
458 configuration and Guix takes care of instantiating the configuration in a
459 transactional, reproducible, and stateless fashion (@pxref{System
460 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
461 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
462 Manual}), the well-known GNU utilities and tool chain, as well as the
463 graphical environment or system services of your choice.
465 Guix System is available on all the above platforms except
466 @code{mips64el-linux}.
469 For information on porting to other architectures or kernels,
472 Building this distribution is a cooperative effort, and you are invited
473 to join! @xref{Contributing}, for information about how you can help.
476 @c *********************************************************************
478 @chapter Installation
480 @cindex installing Guix
483 We recommend the use of this
484 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
485 shell installer script} to install Guix on top of a running GNU/Linux system,
486 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
487 with the installation of the package manager, which can be done on top of a
488 running GNU/Linux system. If, instead, you want to install the complete GNU
489 operating system, @pxref{System Installation}.} The script automates the
490 download, installation, and initial configuration of Guix. It should be run
494 @cindex foreign distro
495 @cindex directories related to foreign distro
496 When installed on a foreign distro, GNU@tie{}Guix complements the available
497 tools without interference. Its data lives exclusively in two directories,
498 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
499 such as @file{/etc}, are left untouched.
501 Once installed, Guix can be updated by running @command{guix pull}
502 (@pxref{Invoking guix pull}).
504 If you prefer to perform the installation steps manually or want to tweak
505 them, you may find the following subsections useful. They describe the
506 software requirements of Guix, as well as how to install it manually and get
510 * Binary Installation:: Getting Guix running in no time!
511 * Requirements:: Software needed to build and run Guix.
512 * Running the Test Suite:: Testing Guix.
513 * Setting Up the Daemon:: Preparing the build daemon's environment.
514 * Invoking guix-daemon:: Running the build daemon.
515 * Application Setup:: Application-specific setup.
518 @node Binary Installation
519 @section Binary Installation
521 @cindex installing Guix from binaries
522 @cindex installer script
523 This section describes how to install Guix on an arbitrary system from a
524 self-contained tarball providing binaries for Guix and for all its
525 dependencies. This is often quicker than installing from source, which
526 is described in the next sections. The only requirement is to have
529 @c Note duplicated from the ``Installation'' node.
531 We recommend the use of this
532 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
533 shell installer script}. The script automates the download, installation, and
534 initial configuration steps described below. It should be run as the root
538 Installing goes along these lines:
542 @cindex downloading Guix binary
543 Download the binary tarball from
544 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz},
545 where @var{system} is @code{x86_64-linux} for an @code{x86_64} machine
546 already running the kernel Linux, and so on.
548 @c The following is somewhat duplicated in ``System Installation''.
549 Make sure to download the associated @file{.sig} file and to verify the
550 authenticity of the tarball against it, along these lines:
553 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
554 $ gpg --verify guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
557 If that command fails because you do not have the required public key,
558 then run this command to import it:
561 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
562 -qO - | gpg --import -
566 and rerun the @code{gpg --verify} command.
568 Take note that a warning like ``This key is not certified with a trusted
569 signature!'' is normal.
571 @c end authentication part
574 Now, you need to become the @code{root} user. Depending on your distribution,
575 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
579 # tar --warning=no-timestamp -xf \
580 /path/to/guix-binary-@value{VERSION}.@var{system}.tar.xz
581 # mv var/guix /var/ && mv gnu /
584 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
585 The latter contains a ready-to-use profile for @code{root} (see next
588 Do @emph{not} unpack the tarball on a working Guix system since that
589 would overwrite its own essential files.
591 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
592 not emit warnings about ``implausibly old time stamps'' (such
593 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
595 They stem from the fact that all the
596 files in the archive have their modification time set to zero (which
597 means January 1st, 1970.) This is done on purpose to make sure the
598 archive content is independent of its creation time, thus making it
602 Make the profile available under @file{~root/.config/guix/current}, which is
603 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
606 # mkdir -p ~root/.config/guix
607 # ln -sf /var/guix/profiles/per-user/root/current-guix \
608 ~root/.config/guix/current
611 Source @file{etc/profile} to augment @code{PATH} and other relevant
612 environment variables:
615 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
616 source $GUIX_PROFILE/etc/profile
620 Create the group and user accounts for build users as explained below
621 (@pxref{Build Environment Setup}).
624 Run the daemon, and set it to automatically start on boot.
626 If your host distro uses the systemd init system, this can be achieved
629 @c Versions of systemd that supported symlinked service files are not
630 @c yet widely deployed, so we should suggest that users copy the service
633 @c See this thread for more information:
634 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
637 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
639 # systemctl start guix-daemon && systemctl enable guix-daemon
642 If your host distro uses the Upstart init system:
645 # initctl reload-configuration
646 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
651 Otherwise, you can still start the daemon manually with:
654 # ~root/.config/guix/current/bin/guix-daemon \
655 --build-users-group=guixbuild
659 Make the @command{guix} command available to other users on the machine,
663 # mkdir -p /usr/local/bin
665 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
668 It is also a good idea to make the Info version of this manual available
672 # mkdir -p /usr/local/share/info
673 # cd /usr/local/share/info
674 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
678 That way, assuming @file{/usr/local/share/info} is in the search path,
679 running @command{info guix} will open this manual (@pxref{Other Info
680 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
684 @cindex substitutes, authorization thereof
685 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
686 (@pxref{Substitutes}), authorize them:
689 # guix archive --authorize < \
690 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
694 Each user may need to perform a few additional steps to make their Guix
695 environment ready for use, @pxref{Application Setup}.
698 Voilà, the installation is complete!
700 You can confirm that Guix is working by installing a sample package into
707 The binary installation tarball can be (re)produced and verified simply
708 by running the following command in the Guix source tree:
711 make guix-binary.@var{system}.tar.xz
715 ...@: which, in turn, runs:
718 guix pack -s @var{system} --localstatedir \
719 --profile-name=current-guix guix
722 @xref{Invoking guix pack}, for more info on this handy tool.
725 @section Requirements
727 This section lists requirements when building Guix from source. The
728 build procedure for Guix is the same as for other GNU software, and is
729 not covered here. Please see the files @file{README} and @file{INSTALL}
730 in the Guix source tree for additional details.
732 @cindex official website
733 GNU Guix is available for download from its website at
734 @url{https://www.gnu.org/software/guix/}.
736 GNU Guix depends on the following packages:
739 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 2.2.x;
740 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
743 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
744 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
745 Guile,, gnutls-guile, GnuTLS-Guile});
747 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
750 @c FIXME: Specify a version number once a release has been made.
751 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
753 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON} 3.x;
754 @item @url{https://zlib.net, zlib};
755 @item @url{https://www.gnu.org/software/make/, GNU Make}.
758 The following dependencies are optional:
762 @c Note: We need at least 0.10.2 for 'channel-send-eof'.
763 Support for build offloading (@pxref{Daemon Offload Setup}) and
764 @command{guix copy} (@pxref{Invoking guix copy}) depends on
765 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
766 version 0.10.2 or later.
769 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
770 substitutes can be used and @command{guix publish} can compress substitutes
774 When @url{http://www.bzip.org, libbz2} is available,
775 @command{guix-daemon} can use it to compress build logs.
778 Unless @code{--disable-daemon} was passed to @command{configure}, the
779 following packages are also needed:
782 @item @url{https://gnupg.org/, GNU libgcrypt};
783 @item @url{https://sqlite.org, SQLite 3};
784 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
788 @cindex state directory
789 When configuring Guix on a system that already has a Guix installation,
790 be sure to specify the same state directory as the existing installation
791 using the @code{--localstatedir} option of the @command{configure}
792 script (@pxref{Directory Variables, @code{localstatedir},, standards,
793 GNU Coding Standards}). The @command{configure} script protects against
794 unintended misconfiguration of @var{localstatedir} so you do not
795 inadvertently corrupt your store (@pxref{The Store}).
797 @cindex Nix, compatibility
798 When a working installation of @url{https://nixos.org/nix/, the Nix package
799 manager} is available, you
800 can instead configure Guix with @code{--disable-daemon}. In that case,
801 Nix replaces the three dependencies above.
803 Guix is compatible with Nix, so it is possible to share the same store
804 between both. To do so, you must pass @command{configure} not only the
805 same @code{--with-store-dir} value, but also the same
806 @code{--localstatedir} value. The latter is essential because it
807 specifies where the database that stores metadata about the store is
808 located, among other things. The default values for Nix are
809 @code{--with-store-dir=/nix/store} and @code{--localstatedir=/nix/var}.
810 Note that @code{--disable-daemon} is not required if
811 your goal is to share the store with Nix.
813 @node Running the Test Suite
814 @section Running the Test Suite
817 After a successful @command{configure} and @code{make} run, it is a good
818 idea to run the test suite. It can help catch issues with the setup or
819 environment, or bugs in Guix itself---and really, reporting test
820 failures is a good way to help improve the software. To run the test
827 Test cases can run in parallel: you can use the @code{-j} option of
828 GNU@tie{}make to speed things up. The first run may take a few minutes
829 on a recent machine; subsequent runs will be faster because the store
830 that is created for test purposes will already have various things in
833 It is also possible to run a subset of the tests by defining the
834 @code{TESTS} makefile variable as in this example:
837 make check TESTS="tests/store.scm tests/cpio.scm"
840 By default, tests results are displayed at a file level. In order to
841 see the details of every individual test cases, it is possible to define
842 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
845 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
848 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
849 @file{test-suite.log} file. Please specify the Guix version being used
850 as well as version numbers of the dependencies (@pxref{Requirements}) in
853 Guix also comes with a whole-system test suite that tests complete
854 Guix System instances. It can only run on systems where
855 Guix is already installed, using:
862 or, again, by defining @code{TESTS} to select a subset of tests to run:
865 make check-system TESTS="basic mcron"
868 These system tests are defined in the @code{(gnu tests @dots{})}
869 modules. They work by running the operating systems under test with
870 lightweight instrumentation in a virtual machine (VM). They can be
871 computationally intensive or rather cheap, depending on whether
872 substitutes are available for their dependencies (@pxref{Substitutes}).
873 Some of them require a lot of storage space to hold VM images.
875 Again in case of test failures, please send @email{bug-guix@@gnu.org}
878 @node Setting Up the Daemon
879 @section Setting Up the Daemon
882 Operations such as building a package or running the garbage collector
883 are all performed by a specialized process, the @dfn{build daemon}, on
884 behalf of clients. Only the daemon may access the store and its
885 associated database. Thus, any operation that manipulates the store
886 goes through the daemon. For instance, command-line tools such as
887 @command{guix package} and @command{guix build} communicate with the
888 daemon (@i{via} remote procedure calls) to instruct it what to do.
890 The following sections explain how to prepare the build daemon's
891 environment. See also @ref{Substitutes}, for information on how to allow
892 the daemon to download pre-built binaries.
895 * Build Environment Setup:: Preparing the isolated build environment.
896 * Daemon Offload Setup:: Offloading builds to remote machines.
897 * SELinux Support:: Using an SELinux policy for the daemon.
900 @node Build Environment Setup
901 @subsection Build Environment Setup
903 @cindex build environment
904 In a standard multi-user setup, Guix and its daemon---the
905 @command{guix-daemon} program---are installed by the system
906 administrator; @file{/gnu/store} is owned by @code{root} and
907 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
908 Guix tools to build packages or otherwise access the store, and the
909 daemon will do it on their behalf, ensuring that the store is kept in a
910 consistent state, and allowing built packages to be shared among users.
913 When @command{guix-daemon} runs as @code{root}, you may not want package
914 build processes themselves to run as @code{root} too, for obvious
915 security reasons. To avoid that, a special pool of @dfn{build users}
916 should be created for use by build processes started by the daemon.
917 These build users need not have a shell and a home directory: they will
918 just be used when the daemon drops @code{root} privileges in build
919 processes. Having several such users allows the daemon to launch
920 distinct build processes under separate UIDs, which guarantees that they
921 do not interfere with each other---an essential feature since builds are
922 regarded as pure functions (@pxref{Introduction}).
924 On a GNU/Linux system, a build user pool may be created like this (using
925 Bash syntax and the @code{shadow} commands):
927 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
928 @c for why `-G' is needed.
930 # groupadd --system guixbuild
931 # for i in `seq -w 1 10`;
933 useradd -g guixbuild -G guixbuild \
934 -d /var/empty -s `which nologin` \
935 -c "Guix build user $i" --system \
941 The number of build users determines how many build jobs may run in
942 parallel, as specified by the @option{--max-jobs} option
943 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
944 @command{guix system vm} and related commands, you may need to add the
945 build users to the @code{kvm} group so they can access @file{/dev/kvm},
946 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
947 (@pxref{Invoking guix system}).
949 The @code{guix-daemon} program may then be run as @code{root} with the
950 following command@footnote{If your machine uses the systemd init system,
951 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
952 file in @file{/etc/systemd/system} will ensure that
953 @command{guix-daemon} is automatically started. Similarly, if your
954 machine uses the Upstart init system, drop the
955 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
956 file in @file{/etc/init}.}:
959 # guix-daemon --build-users-group=guixbuild
964 This way, the daemon starts build processes in a chroot, under one of
965 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
966 environment contains nothing but:
968 @c Keep this list in sync with libstore/build.cc! -----------------------
971 a minimal @code{/dev} directory, created mostly independently from the
972 host @code{/dev}@footnote{``Mostly'', because while the set of files
973 that appear in the chroot's @code{/dev} is fixed, most of these files
974 can only be created if the host has them.};
977 the @code{/proc} directory; it only shows the processes of the container
978 since a separate PID name space is used;
981 @file{/etc/passwd} with an entry for the current user and an entry for
985 @file{/etc/group} with an entry for the user's group;
988 @file{/etc/hosts} with an entry that maps @code{localhost} to
992 a writable @file{/tmp} directory.
995 You can influence the directory where the daemon stores build trees
996 @i{via} the @code{TMPDIR} environment variable. However, the build tree
997 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
998 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
999 This way, the value of @code{TMPDIR} does not leak inside build
1000 environments, which avoids discrepancies in cases where build processes
1001 capture the name of their build tree.
1004 The daemon also honors the @code{http_proxy} environment variable for
1005 HTTP downloads it performs, be it for fixed-output derivations
1006 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1008 If you are installing Guix as an unprivileged user, it is still possible
1009 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1010 However, build processes will not be isolated from one another, and not
1011 from the rest of the system. Thus, build processes may interfere with
1012 each other, and may access programs, libraries, and other files
1013 available on the system---making it much harder to view them as
1014 @emph{pure} functions.
1017 @node Daemon Offload Setup
1018 @subsection Using the Offload Facility
1022 When desired, the build daemon can @dfn{offload} derivation builds to
1023 other machines running Guix, using the @code{offload} @dfn{build
1024 hook}@footnote{This feature is available only when
1025 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1026 present.}. When that
1027 feature is enabled, a list of user-specified build machines is read from
1028 @file{/etc/guix/machines.scm}; every time a build is requested, for
1029 instance via @code{guix build}, the daemon attempts to offload it to one
1030 of the machines that satisfy the constraints of the derivation, in
1031 particular its system type---e.g., @file{x86_64-linux}. Missing
1032 prerequisites for the build are copied over SSH to the target machine,
1033 which then proceeds with the build; upon success the output(s) of the
1034 build are copied back to the initial machine.
1036 The @file{/etc/guix/machines.scm} file typically looks like this:
1039 (list (build-machine
1040 (name "eightysix.example.org")
1041 (system "x86_64-linux")
1042 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1044 (speed 2.)) ;incredibly fast!
1047 (name "meeps.example.org")
1048 (system "mips64el-linux")
1049 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1052 (string-append (getenv "HOME")
1053 "/.ssh/identity-for-guix"))))
1057 In the example above we specify a list of two build machines, one for
1058 the @code{x86_64} architecture and one for the @code{mips64el}
1061 In fact, this file is---not surprisingly!---a Scheme file that is
1062 evaluated when the @code{offload} hook is started. Its return value
1063 must be a list of @code{build-machine} objects. While this example
1064 shows a fixed list of build machines, one could imagine, say, using
1065 DNS-SD to return a list of potential build machines discovered in the
1066 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1067 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1070 @deftp {Data Type} build-machine
1071 This data type represents build machines to which the daemon may offload
1072 builds. The important fields are:
1077 The host name of the remote machine.
1080 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1083 The user account to use when connecting to the remote machine over SSH.
1084 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1085 allow non-interactive logins.
1088 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1089 This is used to authenticate the machine when we connect to it. It is a
1090 long string that looks like this:
1093 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1096 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1097 key can be found in a file such as
1098 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1100 If the machine is running the SSH daemon of GNU@tie{}lsh,
1101 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1102 similar file. It can be converted to the OpenSSH format using
1103 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1106 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1107 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1112 A number of optional fields may be specified:
1116 @item @code{port} (default: @code{22})
1117 Port number of SSH server on the machine.
1119 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1120 The SSH private key file to use when connecting to the machine, in
1121 OpenSSH format. This key must not be protected with a passphrase.
1123 Note that the default value is the private key @emph{of the root
1124 account}. Make sure it exists if you use the default.
1126 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1127 @itemx @code{compression-level} (default: @code{3})
1128 The SSH-level compression methods and compression level requested.
1130 Note that offloading relies on SSH compression to reduce bandwidth usage
1131 when transferring files to and from build machines.
1133 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1134 File name of the Unix-domain socket @command{guix-daemon} is listening
1137 @item @code{parallel-builds} (default: @code{1})
1138 The number of builds that may run in parallel on the machine.
1140 @item @code{speed} (default: @code{1.0})
1141 A ``relative speed factor''. The offload scheduler will tend to prefer
1142 machines with a higher speed factor.
1144 @item @code{features} (default: @code{'()})
1145 A list of strings denoting specific features supported by the machine.
1146 An example is @code{"kvm"} for machines that have the KVM Linux modules
1147 and corresponding hardware support. Derivations can request features by
1148 name, and they will be scheduled on matching build machines.
1153 The @command{guix} command must be in the search path on the build
1154 machines. You can check whether this is the case by running:
1157 ssh build-machine guix repl --version
1160 There is one last thing to do once @file{machines.scm} is in place. As
1161 explained above, when offloading, files are transferred back and forth
1162 between the machine stores. For this to work, you first need to
1163 generate a key pair on each machine to allow the daemon to export signed
1164 archives of files from the store (@pxref{Invoking guix archive}):
1167 # guix archive --generate-key
1171 Each build machine must authorize the key of the master machine so that
1172 it accepts store items it receives from the master:
1175 # guix archive --authorize < master-public-key.txt
1179 Likewise, the master machine must authorize the key of each build machine.
1181 All the fuss with keys is here to express pairwise mutual trust
1182 relations between the master and the build machines. Concretely, when
1183 the master receives files from a build machine (and @i{vice versa}), its
1184 build daemon can make sure they are genuine, have not been tampered
1185 with, and that they are signed by an authorized key.
1187 @cindex offload test
1188 To test whether your setup is operational, run this command on the
1195 This will attempt to connect to each of the build machines specified in
1196 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1197 available on each machine, attempt to export to the machine and import
1198 from it, and report any error in the process.
1200 If you want to test a different machine file, just specify it on the
1204 # guix offload test machines-qualif.scm
1207 Last, you can test the subset of the machines whose name matches a
1208 regular expression like this:
1211 # guix offload test machines.scm '\.gnu\.org$'
1214 @cindex offload status
1215 To display the current load of all build hosts, run this command on the
1219 # guix offload status
1223 @node SELinux Support
1224 @subsection SELinux Support
1226 @cindex SELinux, daemon policy
1227 @cindex mandatory access control, SELinux
1228 @cindex security, guix-daemon
1229 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1230 can be installed on a system where SELinux is enabled, in order to label
1231 Guix files and to specify the expected behavior of the daemon. Since
1232 Guix System does not provide an SELinux base policy, the daemon policy cannot
1233 be used on Guix System.
1235 @subsubsection Installing the SELinux policy
1236 @cindex SELinux, policy installation
1237 To install the policy run this command as root:
1240 semodule -i etc/guix-daemon.cil
1243 Then relabel the file system with @code{restorecon} or by a different
1244 mechanism provided by your system.
1246 Once the policy is installed, the file system has been relabeled, and
1247 the daemon has been restarted, it should be running in the
1248 @code{guix_daemon_t} context. You can confirm this with the following
1252 ps -Zax | grep guix-daemon
1255 Monitor the SELinux log files as you run a command like @code{guix build
1256 hello} to convince yourself that SELinux permits all necessary
1259 @subsubsection Limitations
1260 @cindex SELinux, limitations
1262 This policy is not perfect. Here is a list of limitations or quirks
1263 that should be considered when deploying the provided SELinux policy for
1268 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1269 operations involve contexts that have anything to do with
1270 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1271 but it would be preferrable to define socket rules for only this label.
1274 @code{guix gc} cannot access arbitrary links to profiles. By design,
1275 the file label of the destination of a symlink is independent of the
1276 file label of the link itself. Although all profiles under
1277 $localstatedir are labelled, the links to these profiles inherit the
1278 label of the directory they are in. For links in the user’s home
1279 directory this will be @code{user_home_t}. But for links from the root
1280 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1281 directory, etc, this won’t work. @code{guix gc} would be prevented from
1282 reading and following these links.
1285 The daemon’s feature to listen for TCP connections might no longer work.
1286 This might require extra rules, because SELinux treats network sockets
1287 differently from files.
1290 Currently all files with a name matching the regular expression
1291 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1292 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1293 that name in any profile would be permitted to run in the
1294 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1295 build a package that provides this executable and convince a user to
1296 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1297 At that point SELinux could not prevent it from accessing files that are
1298 allowed for processes in that domain.
1300 We could generate a much more restrictive policy at installation time,
1301 so that only the @emph{exact} file name of the currently installed
1302 @code{guix-daemon} executable would be labelled with
1303 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1304 The downside is that root would have to install or upgrade the policy at
1305 installation time whenever the Guix package that provides the
1306 effectively running @code{guix-daemon} executable is upgraded.
1309 @node Invoking guix-daemon
1310 @section Invoking @command{guix-daemon}
1312 The @command{guix-daemon} program implements all the functionality to
1313 access the store. This includes launching build processes, running the
1314 garbage collector, querying the availability of a build result, etc. It
1315 is normally run as @code{root} like this:
1318 # guix-daemon --build-users-group=guixbuild
1322 For details on how to set it up, @pxref{Setting Up the Daemon}.
1325 @cindex container, build environment
1326 @cindex build environment
1327 @cindex reproducible builds
1328 By default, @command{guix-daemon} launches build processes under
1329 different UIDs, taken from the build group specified with
1330 @code{--build-users-group}. In addition, each build process is run in a
1331 chroot environment that only contains the subset of the store that the
1332 build process depends on, as specified by its derivation
1333 (@pxref{Programming Interface, derivation}), plus a set of specific
1334 system directories. By default, the latter contains @file{/dev} and
1335 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1336 @dfn{container}: in addition to having its own file system tree, it has
1337 a separate mount name space, its own PID name space, network name space,
1338 etc. This helps achieve reproducible builds (@pxref{Features}).
1340 When the daemon performs a build on behalf of the user, it creates a
1341 build directory under @file{/tmp} or under the directory specified by
1342 its @code{TMPDIR} environment variable. This directory is shared with
1343 the container for the duration of the build, though within the container,
1344 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1346 The build directory is automatically deleted upon completion, unless the
1347 build failed and the client specified @option{--keep-failed}
1348 (@pxref{Invoking guix build, @option{--keep-failed}}).
1350 The daemon listens for connections and spawns one sub-process for each session
1351 started by a client (one of the @command{guix} sub-commands.) The
1352 @command{guix processes} command allows you to get an overview of the activity
1353 on your system by viewing each of the active sessions and clients.
1354 @xref{Invoking guix processes}, for more information.
1356 The following command-line options are supported:
1359 @item --build-users-group=@var{group}
1360 Take users from @var{group} to run build processes (@pxref{Setting Up
1361 the Daemon, build users}).
1363 @item --no-substitutes
1365 Do not use substitutes for build products. That is, always build things
1366 locally instead of allowing downloads of pre-built binaries
1367 (@pxref{Substitutes}).
1369 When the daemon runs with @code{--no-substitutes}, clients can still
1370 explicitly enable substitution @i{via} the @code{set-build-options}
1371 remote procedure call (@pxref{The Store}).
1373 @item --substitute-urls=@var{urls}
1374 @anchor{daemon-substitute-urls}
1375 Consider @var{urls} the default whitespace-separated list of substitute
1376 source URLs. When this option is omitted,
1377 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1379 This means that substitutes may be downloaded from @var{urls}, as long
1380 as they are signed by a trusted signature (@pxref{Substitutes}).
1383 @item --no-build-hook
1384 Do not use the @dfn{build hook}.
1386 The build hook is a helper program that the daemon can start and to
1387 which it submits build requests. This mechanism is used to offload
1388 builds to other machines (@pxref{Daemon Offload Setup}).
1390 @item --cache-failures
1391 Cache build failures. By default, only successful builds are cached.
1393 When this option is used, @command{guix gc --list-failures} can be used
1394 to query the set of store items marked as failed; @command{guix gc
1395 --clear-failures} removes store items from the set of cached failures.
1396 @xref{Invoking guix gc}.
1398 @item --cores=@var{n}
1400 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1403 The default value is @code{0}, but it may be overridden by clients, such
1404 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1407 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1408 in the build process, which can then use it to exploit internal
1409 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1411 @item --max-jobs=@var{n}
1413 Allow at most @var{n} build jobs in parallel. The default value is
1414 @code{1}. Setting it to @code{0} means that no builds will be performed
1415 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1416 Setup}), or simply fail.
1418 @item --max-silent-time=@var{seconds}
1419 When the build or substitution process remains silent for more than
1420 @var{seconds}, terminate it and report a build failure.
1422 The default value is @code{0}, which disables the timeout.
1424 The value specified here can be overridden by clients (@pxref{Common
1425 Build Options, @code{--max-silent-time}}).
1427 @item --timeout=@var{seconds}
1428 Likewise, when the build or substitution process lasts for more than
1429 @var{seconds}, terminate it and report a build failure.
1431 The default value is @code{0}, which disables the timeout.
1433 The value specified here can be overridden by clients (@pxref{Common
1434 Build Options, @code{--timeout}}).
1436 @item --rounds=@var{N}
1437 Build each derivation @var{n} times in a row, and raise an error if
1438 consecutive build results are not bit-for-bit identical. Note that this
1439 setting can be overridden by clients such as @command{guix build}
1440 (@pxref{Invoking guix build}).
1442 When used in conjunction with @option{--keep-failed}, the differing
1443 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1444 This makes it easy to look for differences between the two results.
1447 Produce debugging output.
1449 This is useful to debug daemon start-up issues, but then it may be
1450 overridden by clients, for example the @code{--verbosity} option of
1451 @command{guix build} (@pxref{Invoking guix build}).
1453 @item --chroot-directory=@var{dir}
1454 Add @var{dir} to the build chroot.
1456 Doing this may change the result of build processes---for instance if
1457 they use optional dependencies found in @var{dir} when it is available,
1458 and not otherwise. For that reason, it is not recommended to do so.
1459 Instead, make sure that each derivation declares all the inputs that it
1462 @item --disable-chroot
1463 Disable chroot builds.
1465 Using this option is not recommended since, again, it would allow build
1466 processes to gain access to undeclared dependencies. It is necessary,
1467 though, when @command{guix-daemon} is running under an unprivileged user
1470 @item --log-compression=@var{type}
1471 Compress build logs according to @var{type}, one of @code{gzip},
1472 @code{bzip2}, or @code{none}.
1474 Unless @code{--lose-logs} is used, all the build logs are kept in the
1475 @var{localstatedir}. To save space, the daemon automatically compresses
1476 them with bzip2 by default.
1478 @item --disable-deduplication
1479 @cindex deduplication
1480 Disable automatic file ``deduplication'' in the store.
1482 By default, files added to the store are automatically ``deduplicated'':
1483 if a newly added file is identical to another one found in the store,
1484 the daemon makes the new file a hard link to the other file. This can
1485 noticeably reduce disk usage, at the expense of slightly increased
1486 input/output load at the end of a build process. This option disables
1489 @item --gc-keep-outputs[=yes|no]
1490 Tell whether the garbage collector (GC) must keep outputs of live
1494 @cindex garbage collector roots
1495 When set to ``yes'', the GC will keep the outputs of any live derivation
1496 available in the store---the @code{.drv} files. The default is ``no'',
1497 meaning that derivation outputs are kept only if they are reachable from a GC
1498 root. @xref{Invoking guix gc}, for more on GC roots.
1500 @item --gc-keep-derivations[=yes|no]
1501 Tell whether the garbage collector (GC) must keep derivations
1502 corresponding to live outputs.
1504 When set to ``yes'', as is the case by default, the GC keeps
1505 derivations---i.e., @code{.drv} files---as long as at least one of their
1506 outputs is live. This allows users to keep track of the origins of
1507 items in their store. Setting it to ``no'' saves a bit of disk space.
1509 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1510 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1511 ``yes'' causes liveness to flow from derivations to outputs. When both are
1512 set to ``yes'', the effect is to keep all the build prerequisites (the
1513 sources, compiler, libraries, and other build-time tools) of live objects in
1514 the store, regardless of whether these prerequisites are reachable from a GC
1515 root. This is convenient for developers since it saves rebuilds or downloads.
1517 @item --impersonate-linux-2.6
1518 On Linux-based systems, impersonate Linux 2.6. This means that the
1519 kernel's @code{uname} system call will report 2.6 as the release number.
1521 This might be helpful to build programs that (usually wrongfully) depend
1522 on the kernel version number.
1525 Do not keep build logs. By default they are kept under
1526 @code{@var{localstatedir}/guix/log}.
1528 @item --system=@var{system}
1529 Assume @var{system} as the current system type. By default it is the
1530 architecture/kernel pair found at configure time, such as
1531 @code{x86_64-linux}.
1533 @item --listen=@var{endpoint}
1534 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1535 as the file name of a Unix-domain socket if it starts with
1536 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1537 host name or host name and port to listen to. Here are a few examples:
1540 @item --listen=/gnu/var/daemon
1541 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1542 creating it if needed.
1544 @item --listen=localhost
1545 @cindex daemon, remote access
1546 @cindex remote access to the daemon
1547 @cindex daemon, cluster setup
1548 @cindex clusters, daemon setup
1549 Listen for TCP connections on the network interface corresponding to
1550 @code{localhost}, on port 44146.
1552 @item --listen=128.0.0.42:1234
1553 Listen for TCP connections on the network interface corresponding to
1554 @code{128.0.0.42}, on port 1234.
1557 This option can be repeated multiple times, in which case
1558 @command{guix-daemon} accepts connections on all the specified
1559 endpoints. Users can tell client commands what endpoint to connect to
1560 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1561 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1564 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1565 @code{--listen=@var{host}} is suitable on local networks, such as
1566 clusters, where only trusted nodes may connect to the build daemon. In
1567 other cases where remote access to the daemon is needed, we recommend
1568 using Unix-domain sockets along with SSH.
1571 When @code{--listen} is omitted, @command{guix-daemon} listens for
1572 connections on the Unix-domain socket located at
1573 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1577 @node Application Setup
1578 @section Application Setup
1580 @cindex foreign distro
1581 When using Guix on top of GNU/Linux distribution other than Guix System---a
1582 so-called @dfn{foreign distro}---a few additional steps are needed to
1583 get everything in place. Here are some of them.
1587 @anchor{locales-and-locpath}
1588 @cindex locales, when not on Guix System
1590 @vindex GUIX_LOCPATH
1591 Packages installed @i{via} Guix will not use the locale data of the
1592 host system. Instead, you must first install one of the locale packages
1593 available with Guix and then define the @code{GUIX_LOCPATH} environment
1597 $ guix install glibc-locales
1598 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1601 Note that the @code{glibc-locales} package contains data for all the
1602 locales supported by the GNU@tie{}libc and weighs in at around
1603 110@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1604 limited to a few UTF-8 locales.
1606 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1607 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1608 Manual}). There are two important differences though:
1612 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1613 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1614 to make sure the programs of the foreign distro will not end up loading
1615 incompatible locale data.
1618 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1619 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1620 should your Guix profile contain a mixture of programs linked against
1621 different libc version, each libc version will only try to load locale
1622 data in the right format.
1625 This is important because the locale data format used by different libc
1626 versions may be incompatible.
1628 @subsection Name Service Switch
1630 @cindex name service switch, glibc
1631 @cindex NSS (name service switch), glibc
1632 @cindex nscd (name service caching daemon)
1633 @cindex name service caching daemon (nscd)
1634 When using Guix on a foreign distro, we @emph{strongly recommend} that
1635 the system run the GNU C library's @dfn{name service cache daemon},
1636 @command{nscd}, which should be listening on the
1637 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1638 installed with Guix may fail to look up host names or user accounts, or
1639 may even crash. The next paragraphs explain why.
1641 @cindex @file{nsswitch.conf}
1642 The GNU C library implements a @dfn{name service switch} (NSS), which is
1643 an extensible mechanism for ``name lookups'' in general: host name
1644 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1645 The GNU C Library Reference Manual}).
1647 @cindex Network information service (NIS)
1648 @cindex NIS (Network information service)
1649 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1650 lookup implementations: for example, the @code{nss-mdns} plugin allow
1651 resolution of @code{.local} host names, the @code{nis} plugin allows
1652 user account lookup using the Network information service (NIS), and so
1653 on. These extra ``lookup services'' are configured system-wide in
1654 @file{/etc/nsswitch.conf}, and all the programs running on the system
1655 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1658 When they perform a name lookup---for instance by calling the
1659 @code{getaddrinfo} function in C---applications first try to connect to
1660 the nscd; on success, nscd performs name lookups on their behalf. If
1661 the nscd is not running, then they perform the name lookup by
1662 themselves, by loading the name lookup services into their own address
1663 space and running it. These name lookup services---the
1664 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1665 the host system's C library, rather than from the C library the
1666 application is linked against (the C library coming from Guix).
1668 And this is where the problem is: if your application is linked against
1669 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1670 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1671 likely crash or have its name lookups fail unexpectedly.
1673 Running @command{nscd} on the system, among other advantages, eliminates
1674 this binary incompatibility problem because those @code{libnss_*.so}
1675 files are loaded in the @command{nscd} process, not in applications
1678 @subsection X11 Fonts
1681 The majority of graphical applications use Fontconfig to locate and
1682 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1683 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1684 by default. Thus, to allow graphical applications installed with Guix
1685 to display fonts, you have to install fonts with Guix as well.
1686 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1687 @code{font-gnu-freefont-ttf}.
1689 To display text written in Chinese languages, Japanese, or Korean in
1690 graphical applications, consider installing
1691 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1692 has multiple outputs, one per language family (@pxref{Packages with
1693 Multiple Outputs}). For instance, the following command installs fonts
1694 for Chinese languages:
1697 guix install font-adobe-source-han-sans:cn
1700 @cindex @code{xterm}
1701 Older programs such as @command{xterm} do not use Fontconfig and instead
1702 rely on server-side font rendering. Such programs require to specify a
1703 full name of a font using XLFD (X Logical Font Description), like this:
1706 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1709 To be able to use such full names for the TrueType fonts installed in
1710 your Guix profile, you need to extend the font path of the X server:
1712 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1713 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1715 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1718 @cindex @code{xlsfonts}
1719 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1720 to make sure your TrueType fonts are listed there.
1722 @cindex @code{fc-cache}
1724 After installing fonts you may have to refresh the font cache to use
1725 them in applications. The same applies when applications installed via
1726 Guix do not seem to find fonts. To force rebuilding of the font cache
1727 run @code{fc-cache -rv}. The @code{fc-cache} command is provided by
1728 the @code{fontconfig} package.
1730 @subsection X.509 Certificates
1732 @cindex @code{nss-certs}
1733 The @code{nss-certs} package provides X.509 certificates, which allow
1734 programs to authenticate Web servers accessed over HTTPS.
1736 When using Guix on a foreign distro, you can install this package and
1737 define the relevant environment variables so that packages know where to
1738 look for certificates. @xref{X.509 Certificates}, for detailed
1741 @subsection Emacs Packages
1743 @cindex @code{emacs}
1744 When you install Emacs packages with Guix, the elisp files may be placed
1745 either in @file{$HOME/.guix-profile/share/emacs/site-lisp/} or in
1747 @file{$HOME/.guix-profile/share/emacs/site-lisp/guix.d/}. The latter
1748 directory exists because potentially there may exist thousands of Emacs
1749 packages and storing all their files in a single directory may not be
1750 reliable (because of name conflicts). So we think using a separate
1751 directory for each package is a good idea. It is very similar to how
1752 the Emacs package system organizes the file structure (@pxref{Package
1753 Files,,, emacs, The GNU Emacs Manual}).
1755 By default, Emacs (installed with Guix) ``knows'' where these packages
1756 are placed, so you do not need to perform any configuration. If, for
1757 some reason, you want to avoid auto-loading Emacs packages installed
1758 with Guix, you can do so by running Emacs with @code{--no-site-file}
1759 option (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1761 @subsection The GCC toolchain
1766 Guix offers individual compiler packages such as @code{gcc} but if you
1767 are in need of a complete toolchain for compiling and linking source
1768 code what you really want is the @code{gcc-toolchain} package. This
1769 package provides a complete GCC toolchain for C/C++ development,
1770 including GCC itself, the GNU C Library (headers and binaries, plus
1771 debugging symbols in the @code{debug} output), Binutils, and a linker
1774 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
1775 passed to the linker, add corresponding @code{-rpath} arguments, and
1776 invoke the actual linker with this new set of arguments. You can instruct the
1777 wrapper to refuse to link against libraries not in the store by setting the
1778 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
1782 @c *********************************************************************
1783 @node System Installation
1784 @chapter System Installation
1786 @cindex installing Guix System
1787 @cindex Guix System, installation
1788 This section explains how to install Guix System
1789 on a machine. Guix, as a package manager, can
1790 also be installed on top of a running GNU/Linux system,
1791 @pxref{Installation}.
1795 @c This paragraph is for people reading this from tty2 of the
1796 @c installation image.
1797 You are reading this documentation with an Info reader. For details on
1798 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1799 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1800 Info}. Hit @kbd{l} afterwards to come back here.
1802 Alternately, run @command{info info} in another tty to keep the manual
1808 * Limitations:: What you can expect.
1809 * Hardware Considerations:: Supported hardware.
1810 * USB Stick and DVD Installation:: Preparing the installation medium.
1811 * Preparing for Installation:: Networking, partitioning, etc.
1812 * Guided Graphical Installation:: Easy graphical installation.
1813 * Manual Installation:: Manual installation for wizards.
1814 * After System Installation:: When installation succeeded.
1815 * Installing Guix in a VM:: Guix System playground.
1816 * Building the Installation Image:: How this comes to be.
1820 @section Limitations
1822 We consider Guix System to be ready for a wide range of ``desktop'' and server
1823 use cases. The reliability guarantees it provides---transactional upgrades
1824 and rollbacks, reproducibility---make it a solid foundation.
1826 Nevertheless, before you proceed with the installation, be aware of the
1827 following noteworthy limitations applicable to version @value{VERSION}:
1831 Support for the Logical Volume Manager (LVM) is missing.
1834 More and more system services are provided (@pxref{Services}), but some
1838 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1839 as well as a number of X11 window managers. However, KDE is currently
1843 More than a disclaimer, this is an invitation to report issues (and success
1844 stories!), and to join us in improving it. @xref{Contributing}, for more
1848 @node Hardware Considerations
1849 @section Hardware Considerations
1851 @cindex hardware support on Guix System
1852 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1853 builds around the kernel Linux-libre, which means that only hardware for
1854 which free software drivers and firmware exist is supported. Nowadays,
1855 a wide range of off-the-shelf hardware is supported on
1856 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1857 Ethernet controllers. Unfortunately, there are still areas where
1858 hardware vendors deny users control over their own computing, and such
1859 hardware is not supported on Guix System.
1861 @cindex WiFi, hardware support
1862 One of the main areas where free drivers or firmware are lacking is WiFi
1863 devices. WiFi devices known to work include those using Atheros chips
1864 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1865 driver, and those using Broadcom/AirForce chips (BCM43xx with
1866 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1867 Linux-libre driver. Free firmware exists for both and is available
1868 out-of-the-box on Guix System, as part of @code{%base-firmware}
1869 (@pxref{operating-system Reference, @code{firmware}}).
1871 @cindex RYF, Respects Your Freedom
1872 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1873 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1874 certification program for hardware products that respect your freedom
1875 and your privacy and ensure that you have control over your device. We
1876 encourage you to check the list of RYF-certified devices.
1878 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1879 web site. It contains a catalog of hardware devices with information
1880 about their support in GNU/Linux.
1883 @node USB Stick and DVD Installation
1884 @section USB Stick and DVD Installation
1886 An ISO-9660 installation image that can be written to a USB stick or
1887 burnt to a DVD can be downloaded from
1888 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1889 where @var{system} is one of:
1893 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1896 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1899 @c start duplication of authentication part from ``Binary Installation''
1900 Make sure to download the associated @file{.sig} file and to verify the
1901 authenticity of the image against it, along these lines:
1904 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1905 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1908 If that command fails because you do not have the required public key,
1909 then run this command to import it:
1912 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1913 -qO - | gpg --import -
1917 and rerun the @code{gpg --verify} command.
1919 Take note that a warning like ``This key is not certified with a trusted
1920 signature!'' is normal.
1924 This image contains the tools necessary for an installation.
1925 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1927 @unnumberedsubsec Copying to a USB Stick
1929 To copy the image to a USB stick, follow these steps:
1933 Decompress the image using the @command{xz} command:
1936 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1940 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1941 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1942 copy the image with:
1945 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1949 Access to @file{/dev/sdX} usually requires root privileges.
1952 @unnumberedsubsec Burning on a DVD
1954 To copy the image to a DVD, follow these steps:
1958 Decompress the image using the @command{xz} command:
1961 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1965 Insert a blank DVD into your machine, and determine
1966 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
1967 copy the image with:
1970 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
1973 Access to @file{/dev/srX} usually requires root privileges.
1976 @unnumberedsubsec Booting
1978 Once this is done, you should be able to reboot the system and boot from
1979 the USB stick or DVD. The latter usually requires you to get in the
1980 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
1982 @xref{Installing Guix in a VM}, if, instead, you would like to install
1983 Guix System in a virtual machine (VM).
1986 @node Preparing for Installation
1987 @section Preparing for Installation
1989 Once you have booted, you can use the guided graphical installer, which makes
1990 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
1991 if you are already familiar with GNU/Linux and if you want more control than
1992 what the graphical installer provides, you can choose the ``manual''
1993 installation process (@pxref{Manual Installation}).
1995 The graphical installer is available on TTY1. You can obtain root shells on
1996 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
1997 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
1998 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
1999 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2000 which allows you to select text with the left mouse button and to paste it
2001 with the middle button.
2004 Installation requires access to the Internet so that any missing
2005 dependencies of your system configuration can be downloaded. See the
2006 ``Networking'' section below.
2009 @node Guided Graphical Installation
2010 @section Guided Graphical Installation
2012 The graphical installer is a text-based user interface. It will guide you,
2013 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2015 The first dialog boxes allow you to set up the system as you use it during the
2016 installation: you can choose the language, keyboard layout, and set up
2017 networking, which will be used during the installation. The image below shows
2018 the networking dialog.
2020 @image{images/installer-network,5in,, networking setup with the graphical installer}
2022 Later steps allow you to partition your hard disk, as shown in the image
2023 below, to choose whether or not to use encrypted file systems, to enter the
2024 host name and root password, and to create an additional account, among other
2027 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2029 Note that, at any time, the installer allows you to exit the current
2030 installation step and resume at a previous step, as show in the image below.
2032 @image{images/installer-resume,5in,, resuming the installation process}
2034 Once you're done, the installer produces an operating system configuration and
2035 displays it (@pxref{Using the Configuration System}). At that point you can
2036 hit ``OK'' and installation will proceed. On success, you can reboot into the
2037 new system and enjoy. @xref{After System Installation}, for what's next!
2040 @node Manual Installation
2041 @section Manual Installation
2043 This section describes how you would ``manually'' install GNU@tie{}Guix System
2044 on your machine. This option requires familiarity with GNU/Linux, with the
2045 shell, and with common administration tools. If you think this is not for
2046 you, consider using the guided graphical installer (@pxref{Guided Graphical
2049 The installation system provides root shells on TTYs 3 to 6; press
2050 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2051 many common tools needed to install the system. But it is also a full-blown
2052 Guix System, which means that you can install additional packages, should you
2053 need it, using @command{guix package} (@pxref{Invoking guix package}).
2056 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2057 * Proceeding with the Installation:: Installing.
2060 @node Keyboard Layout and Networking and Partitioning
2061 @subsection Keyboard Layout, Networking, and Partitioning
2063 Before you can install the system, you may want to adjust the keyboard layout,
2064 set up networking, and partition your target hard disk. This section will
2065 guide you through this.
2067 @subsubsection Keyboard Layout
2069 @cindex keyboard layout
2070 The installation image uses the US qwerty keyboard layout. If you want
2071 to change it, you can use the @command{loadkeys} command. For example,
2072 the following command selects the Dvorak keyboard layout:
2078 See the files under @file{/run/current-system/profile/share/keymaps} for
2079 a list of available keyboard layouts. Run @command{man loadkeys} for
2082 @subsubsection Networking
2084 Run the following command to see what your network interfaces are called:
2091 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2097 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2098 Wired interfaces have a name starting with @samp{e}; for example, the
2099 interface corresponding to the first on-board Ethernet controller is
2100 called @samp{eno1}. Wireless interfaces have a name starting with
2101 @samp{w}, like @samp{w1p2s0}.
2104 @item Wired connection
2105 To configure a wired network run the following command, substituting
2106 @var{interface} with the name of the wired interface you want to use.
2109 ifconfig @var{interface} up
2112 @item Wireless connection
2115 To configure wireless networking, you can create a configuration file
2116 for the @command{wpa_supplicant} configuration tool (its location is not
2117 important) using one of the available text editors such as
2121 nano wpa_supplicant.conf
2124 As an example, the following stanza can go to this file and will work
2125 for many wireless networks, provided you give the actual SSID and
2126 passphrase for the network you are connecting to:
2130 ssid="@var{my-ssid}"
2132 psk="the network's secret passphrase"
2136 Start the wireless service and run it in the background with the
2137 following command (substitute @var{interface} with the name of the
2138 network interface you want to use):
2141 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2144 Run @command{man wpa_supplicant} for more information.
2148 At this point, you need to acquire an IP address. On a network where IP
2149 addresses are automatically assigned @i{via} DHCP, you can run:
2152 dhclient -v @var{interface}
2155 Try to ping a server to see if networking is up and running:
2161 Setting up network access is almost always a requirement because the
2162 image does not contain all the software and tools that may be needed.
2164 @cindex installing over SSH
2165 If you want to, you can continue the installation remotely by starting
2169 herd start ssh-daemon
2172 Make sure to either set a password with @command{passwd}, or configure
2173 OpenSSH public key authentication before logging in.
2175 @subsubsection Disk Partitioning
2177 Unless this has already been done, the next step is to partition, and
2178 then format the target partition(s).
2180 The installation image includes several partitioning tools, including
2181 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2182 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2183 the partition layout you want:
2189 If your disk uses the GUID Partition Table (GPT) format and you plan to
2190 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2191 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2194 @cindex EFI, installation
2195 @cindex UEFI, installation
2196 @cindex ESP, EFI system partition
2197 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2198 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2199 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2202 parted /dev/sda set 1 esp on
2206 @vindex grub-bootloader
2207 @vindex grub-efi-bootloader
2208 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2209 @file{/sys/firmware/efi} exists in the installation image, then you should
2210 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2211 Otherwise you should use the BIOS-based GRUB, known as
2212 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2216 Once you are done partitioning the target hard disk drive, you have to
2217 create a file system on the relevant partition(s)@footnote{Currently
2218 Guix System only supports ext4 and btrfs file systems. In particular, code
2219 that reads file system UUIDs and labels only works for these file system
2220 types.}. For the ESP, if you have one and assuming it is
2221 @file{/dev/sda1}, run:
2224 mkfs.fat -F32 /dev/sda1
2227 Preferably, assign file systems a label so that you can easily and
2228 reliably refer to them in @code{file-system} declarations (@pxref{File
2229 Systems}). This is typically done using the @code{-L} option of
2230 @command{mkfs.ext4} and related commands. So, assuming the target root
2231 partition lives at @file{/dev/sda2}, a file system with the label
2232 @code{my-root} can be created with:
2235 mkfs.ext4 -L my-root /dev/sda2
2238 @cindex encrypted disk
2239 If you are instead planning to encrypt the root partition, you can use
2240 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2241 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2242 @code{man cryptsetup}} for more information.) Assuming you want to
2243 store the root partition on @file{/dev/sda2}, the command sequence would
2244 be along these lines:
2247 cryptsetup luksFormat /dev/sda2
2248 cryptsetup open --type luks /dev/sda2 my-partition
2249 mkfs.ext4 -L my-root /dev/mapper/my-partition
2252 Once that is done, mount the target file system under @file{/mnt}
2253 with a command like (again, assuming @code{my-root} is the label of the
2257 mount LABEL=my-root /mnt
2260 Also mount any other file systems you would like to use on the target
2261 system relative to this path. If you have opted for @file{/boot/efi} as an
2262 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2263 found by @code{guix system init} afterwards.
2265 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2266 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2267 sure to initialize them with @command{mkswap}. Assuming you have one
2268 swap partition on @file{/dev/sda3}, you would run:
2275 Alternatively, you may use a swap file. For example, assuming that in
2276 the new system you want to use the file @file{/swapfile} as a swap file,
2277 you would run@footnote{This example will work for many types of file
2278 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2279 btrfs), the required steps may be different. For details, see the
2280 manual pages for @command{mkswap} and @command{swapon}.}:
2283 # This is 10 GiB of swap space. Adjust "count" to change the size.
2284 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2285 # For security, make the file readable and writable only by root.
2286 chmod 600 /mnt/swapfile
2287 mkswap /mnt/swapfile
2288 swapon /mnt/swapfile
2291 Note that if you have encrypted the root partition and created a swap
2292 file in its file system as described above, then the encryption also
2293 protects the swap file, just like any other file in that file system.
2295 @node Proceeding with the Installation
2296 @subsection Proceeding with the Installation
2298 With the target partitions ready and the target root mounted on
2299 @file{/mnt}, we're ready to go. First, run:
2302 herd start cow-store /mnt
2305 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2306 during the installation phase are written to the target disk on @file{/mnt}
2307 rather than kept in memory. This is necessary because the first phase of
2308 the @command{guix system init} command (see below) entails downloads or
2309 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2311 Next, you have to edit a file and
2312 provide the declaration of the operating system to be installed. To
2313 that end, the installation system comes with three text editors. We
2314 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2315 supports syntax highlighting and parentheses matching; other editors
2316 include GNU Zile (an Emacs clone), and
2317 nvi (a clone of the original BSD @command{vi} editor).
2318 We strongly recommend storing that file on the target root file system, say,
2319 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2320 configuration file once you have rebooted into the newly-installed system.
2322 @xref{Using the Configuration System}, for an overview of the
2323 configuration file. The example configurations discussed in that
2324 section are available under @file{/etc/configuration} in the
2325 installation image. Thus, to get started with a system configuration
2326 providing a graphical display server (a ``desktop'' system), you can run
2327 something along these lines:
2331 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2332 # nano /mnt/etc/config.scm
2335 You should pay attention to what your configuration file contains, and
2340 Make sure the @code{bootloader-configuration} form refers to the target
2341 you want to install GRUB on. It should mention @code{grub-bootloader} if
2342 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2343 for newer UEFI systems. For legacy systems, the @code{target} field
2344 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2345 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2346 currently mounted and a @code{file-system} entry is specified in your
2350 Be sure that your file system labels match the value of their respective
2351 @code{device} fields in your @code{file-system} configuration, assuming
2352 your @code{file-system} configuration uses the @code{file-system-label}
2353 procedure in its @code{device} field.
2356 If there are encrypted or RAID partitions, make sure to add a
2357 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2360 Once you are done preparing the configuration file, the new system must
2361 be initialized (remember that the target root file system is mounted
2365 guix system init /mnt/etc/config.scm /mnt
2369 This copies all the necessary files and installs GRUB on
2370 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2371 more information, @pxref{Invoking guix system}. This command may trigger
2372 downloads or builds of missing packages, which can take some time.
2374 Once that command has completed---and hopefully succeeded!---you can run
2375 @command{reboot} and boot into the new system. The @code{root} password
2376 in the new system is initially empty; other users' passwords need to be
2377 initialized by running the @command{passwd} command as @code{root},
2378 unless your configuration specifies otherwise
2379 (@pxref{user-account-password, user account passwords}).
2380 @xref{After System Installation}, for what's next!
2383 @node After System Installation
2384 @section After System Installation
2386 Success, you've now booted into Guix System! From then on, you can update the
2387 system whenever you want by running, say:
2391 sudo guix system reconfigure /etc/config.scm
2395 This builds a new system generation with the latest packages and services
2396 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2397 your system includes the latest security updates (@pxref{Security Updates}).
2399 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2401 @cindex sudo vs. @command{guix pull}
2402 Note that @command{sudo guix} runs your user's @command{guix} command and
2403 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2404 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2407 Join us on @code{#guix} on the Freenode IRC network or on
2408 @email{guix-devel@@gnu.org} to share your experience!
2411 @node Installing Guix in a VM
2412 @section Installing Guix in a Virtual Machine
2414 @cindex virtual machine, Guix System installation
2415 @cindex virtual private server (VPS)
2416 @cindex VPS (virtual private server)
2417 If you'd like to install Guix System in a virtual machine (VM) or on a
2418 virtual private server (VPS) rather than on your beloved machine, this
2421 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2422 disk image, follow these steps:
2426 First, retrieve and decompress the Guix system installation image as
2427 described previously (@pxref{USB Stick and DVD Installation}).
2430 Create a disk image that will hold the installed system. To make a
2431 qcow2-formatted disk image, use the @command{qemu-img} command:
2434 qemu-img create -f qcow2 guix-system.img 50G
2437 The resulting file will be much smaller than 50 GB (typically less than
2438 1 MB), but it will grow as the virtualized storage device is filled up.
2441 Boot the USB installation image in an VM:
2444 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2445 -net user -net nic,model=virtio -boot menu=on,order=d \
2446 -drive file=guix-system.img \
2447 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2450 @code{-enable-kvm} is optional, but significantly improves performance,
2451 @pxref{Running Guix in a VM}.
2454 You're now root in the VM, proceed with the installation process.
2455 @xref{Preparing for Installation}, and follow the instructions.
2458 Once installation is complete, you can boot the system that's on your
2459 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2462 @node Building the Installation Image
2463 @section Building the Installation Image
2465 @cindex installation image
2466 The installation image described above was built using the @command{guix
2467 system} command, specifically:
2470 guix system disk-image --file-system-type=iso9660 \
2471 gnu/system/install.scm
2474 Have a look at @file{gnu/system/install.scm} in the source tree,
2475 and see also @ref{Invoking guix system} for more information
2476 about the installation image.
2478 @section Building the Installation Image for ARM Boards
2480 Many ARM boards require a specific variant of the
2481 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2483 If you build a disk image and the bootloader is not available otherwise
2484 (on another boot drive etc), it's advisable to build an image that
2485 includes the bootloader, specifically:
2488 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2491 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2492 board, a list of possible boards will be printed.
2494 @c *********************************************************************
2495 @node Package Management
2496 @chapter Package Management
2499 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2500 remove software packages, without having to know about their build
2501 procedures or dependencies. Guix also goes beyond this obvious set of
2504 This chapter describes the main features of Guix, as well as the
2505 package management tools it provides. Along with the command-line
2506 interface described below (@pxref{Invoking guix package, @code{guix
2507 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2508 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2509 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2513 guix install emacs-guix
2517 * Features:: How Guix will make your life brighter.
2518 * Invoking guix package:: Package installation, removal, etc.
2519 * Substitutes:: Downloading pre-built binaries.
2520 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2521 * Invoking guix gc:: Running the garbage collector.
2522 * Invoking guix pull:: Fetching the latest Guix and distribution.
2523 * Channels:: Customizing the package collection.
2524 * Inferiors:: Interacting with another revision of Guix.
2525 * Invoking guix describe:: Display information about your Guix revision.
2526 * Invoking guix archive:: Exporting and importing store files.
2532 When using Guix, each package ends up in the @dfn{package store}, in its
2533 own directory---something that resembles
2534 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2536 Instead of referring to these directories, users have their own
2537 @dfn{profile}, which points to the packages that they actually want to
2538 use. These profiles are stored within each user's home directory, at
2539 @code{$HOME/.guix-profile}.
2541 For example, @code{alice} installs GCC 4.7.2. As a result,
2542 @file{/home/alice/.guix-profile/bin/gcc} points to
2543 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2544 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2545 simply continues to point to
2546 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2547 coexist on the same system without any interference.
2549 The @command{guix package} command is the central tool to manage
2550 packages (@pxref{Invoking guix package}). It operates on the per-user
2551 profiles, and can be used @emph{with normal user privileges}.
2553 @cindex transactions
2554 The command provides the obvious install, remove, and upgrade
2555 operations. Each invocation is actually a @emph{transaction}: either
2556 the specified operation succeeds, or nothing happens. Thus, if the
2557 @command{guix package} process is terminated during the transaction,
2558 or if a power outage occurs during the transaction, then the user's
2559 profile remains in its previous state, and remains usable.
2561 In addition, any package transaction may be @emph{rolled back}. So, if,
2562 for example, an upgrade installs a new version of a package that turns
2563 out to have a serious bug, users may roll back to the previous instance
2564 of their profile, which was known to work well. Similarly, the global
2565 system configuration on Guix is subject to
2566 transactional upgrades and roll-back
2567 (@pxref{Using the Configuration System}).
2569 All packages in the package store may be @emph{garbage-collected}.
2570 Guix can determine which packages are still referenced by user
2571 profiles, and remove those that are provably no longer referenced
2572 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2573 generations of their profile so that the packages they refer to can be
2576 @cindex reproducibility
2577 @cindex reproducible builds
2578 Guix takes a @dfn{purely functional} approach to package
2579 management, as described in the introduction (@pxref{Introduction}).
2580 Each @file{/gnu/store} package directory name contains a hash of all the
2581 inputs that were used to build that package---compiler, libraries, build
2582 scripts, etc. This direct correspondence allows users to make sure a
2583 given package installation matches the current state of their
2584 distribution. It also helps maximize @dfn{build reproducibility}:
2585 thanks to the isolated build environments that are used, a given build
2586 is likely to yield bit-identical files when performed on different
2587 machines (@pxref{Invoking guix-daemon, container}).
2590 This foundation allows Guix to support @dfn{transparent binary/source
2591 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2592 available from an external source---a @dfn{substitute}, Guix just
2593 downloads it and unpacks it;
2594 otherwise, it builds the package from source, locally
2595 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2596 reproducible, users do not have to trust servers that provide
2597 substitutes: they can force a local build and @emph{challenge} providers
2598 (@pxref{Invoking guix challenge}).
2600 Control over the build environment is a feature that is also useful for
2601 developers. The @command{guix environment} command allows developers of
2602 a package to quickly set up the right development environment for their
2603 package, without having to manually install the dependencies of the
2604 package into their profile (@pxref{Invoking guix environment}).
2606 @cindex replication, of software environments
2607 @cindex provenance tracking, of software artifacts
2608 All of Guix and its package definitions is version-controlled, and
2609 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2610 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2611 Guix instance on a different machine or at a later point in time, which in
2612 turn allows you to @emph{replicate complete software environments}, while
2613 retaining precise @dfn{provenance tracking} of the software.
2615 @node Invoking guix package
2616 @section Invoking @command{guix package}
2618 @cindex installing packages
2619 @cindex removing packages
2620 @cindex package installation
2621 @cindex package removal
2622 The @command{guix package} command is the tool that allows users to
2623 install, upgrade, and remove packages, as well as rolling back to
2624 previous configurations. It operates only on the user's own profile,
2625 and works with normal user privileges (@pxref{Features}). Its syntax
2629 guix package @var{options}
2632 @cindex transactions
2633 Primarily, @var{options} specifies the operations to be performed during
2634 the transaction. Upon completion, a new profile is created, but
2635 previous @dfn{generations} of the profile remain available, should the user
2638 For example, to remove @code{lua} and install @code{guile} and
2639 @code{guile-cairo} in a single transaction:
2642 guix package -r lua -i guile guile-cairo
2645 @cindex aliases, for @command{guix package}
2646 For your convenience, we also provide the following aliases:
2650 @command{guix search} is an alias for @command{guix package -s},
2652 @command{guix install} is an alias for @command{guix package -i},
2654 @command{guix remove} is an alias for @command{guix package -r},
2656 @command{guix upgrade} is an alias for @command{guix package -u},
2658 and @command{guix show} is an alias for @command{guix package --show=}.
2661 These aliases are less expressive than @command{guix package} and provide
2662 fewer options, so in some cases you'll probably want to use @command{guix
2665 @command{guix package} also supports a @dfn{declarative approach}
2666 whereby the user specifies the exact set of packages to be available and
2667 passes it @i{via} the @option{--manifest} option
2668 (@pxref{profile-manifest, @option{--manifest}}).
2671 For each user, a symlink to the user's default profile is automatically
2672 created in @file{$HOME/.guix-profile}. This symlink always points to the
2673 current generation of the user's default profile. Thus, users can add
2674 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2675 variable, and so on.
2676 @cindex search paths
2677 If you are not using Guix System, consider adding the
2678 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2679 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2680 shells get all the right environment variable definitions:
2683 GUIX_PROFILE="$HOME/.guix-profile" ; \
2684 source "$HOME/.guix-profile/etc/profile"
2687 In a multi-user setup, user profiles are stored in a place registered as
2688 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2689 to (@pxref{Invoking guix gc}). That directory is normally
2690 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2691 @var{localstatedir} is the value passed to @code{configure} as
2692 @code{--localstatedir}, and @var{user} is the user name. The
2693 @file{per-user} directory is created when @command{guix-daemon} is
2694 started, and the @var{user} sub-directory is created by @command{guix
2697 The @var{options} can be among the following:
2701 @item --install=@var{package} @dots{}
2702 @itemx -i @var{package} @dots{}
2703 Install the specified @var{package}s.
2705 Each @var{package} may specify either a simple package name, such as
2706 @code{guile}, or a package name followed by an at-sign and version number,
2707 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2708 case, the newest version prefixed by @code{1.8} is selected.)
2710 If no version number is specified, the
2711 newest available version will be selected. In addition, @var{package}
2712 may contain a colon, followed by the name of one of the outputs of the
2713 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2714 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2715 name (and optionally version) are searched for among the GNU
2716 distribution modules (@pxref{Package Modules}).
2718 @cindex propagated inputs
2719 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2720 that automatically get installed along with the required package
2721 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2722 @code{package} objects}, for information about propagated inputs in
2723 package definitions).
2725 @anchor{package-cmd-propagated-inputs}
2726 An example is the GNU MPC library: its C header files refer to those of
2727 the GNU MPFR library, which in turn refer to those of the GMP library.
2728 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2729 in the profile; removing MPC also removes MPFR and GMP---unless they had
2730 also been explicitly installed by the user.
2732 Besides, packages sometimes rely on the definition of environment
2733 variables for their search paths (see explanation of
2734 @code{--search-paths} below). Any missing or possibly incorrect
2735 environment variable definitions are reported here.
2737 @item --install-from-expression=@var{exp}
2739 Install the package @var{exp} evaluates to.
2741 @var{exp} must be a Scheme expression that evaluates to a
2742 @code{<package>} object. This option is notably useful to disambiguate
2743 between same-named variants of a package, with expressions such as
2744 @code{(@@ (gnu packages base) guile-final)}.
2746 Note that this option installs the first output of the specified
2747 package, which may be insufficient when needing a specific output of a
2748 multiple-output package.
2750 @item --install-from-file=@var{file}
2751 @itemx -f @var{file}
2752 Install the package that the code within @var{file} evaluates to.
2754 As an example, @var{file} might contain a definition like this
2755 (@pxref{Defining Packages}):
2758 @include package-hello.scm
2761 Developers may find it useful to include such a @file{guix.scm} file
2762 in the root of their project source tree that can be used to test
2763 development snapshots and create reproducible development environments
2764 (@pxref{Invoking guix environment}).
2766 @item --remove=@var{package} @dots{}
2767 @itemx -r @var{package} @dots{}
2768 Remove the specified @var{package}s.
2770 As for @code{--install}, each @var{package} may specify a version number
2771 and/or output name in addition to the package name. For instance,
2772 @code{-r glibc:debug} would remove the @code{debug} output of
2775 @item --upgrade[=@var{regexp} @dots{}]
2776 @itemx -u [@var{regexp} @dots{}]
2777 @cindex upgrading packages
2778 Upgrade all the installed packages. If one or more @var{regexp}s are
2779 specified, upgrade only installed packages whose name matches a
2780 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2782 Note that this upgrades package to the latest version of packages found
2783 in the distribution currently installed. To update your distribution,
2784 you should regularly run @command{guix pull} (@pxref{Invoking guix
2787 @item --do-not-upgrade[=@var{regexp} @dots{}]
2788 When used together with the @code{--upgrade} option, do @emph{not}
2789 upgrade any packages whose name matches a @var{regexp}. For example, to
2790 upgrade all packages in the current profile except those containing the
2791 substring ``emacs'':
2794 $ guix package --upgrade . --do-not-upgrade emacs
2797 @item @anchor{profile-manifest}--manifest=@var{file}
2798 @itemx -m @var{file}
2799 @cindex profile declaration
2800 @cindex profile manifest
2801 Create a new generation of the profile from the manifest object
2802 returned by the Scheme code in @var{file}.
2804 This allows you to @emph{declare} the profile's contents rather than
2805 constructing it through a sequence of @code{--install} and similar
2806 commands. The advantage is that @var{file} can be put under version
2807 control, copied to different machines to reproduce the same profile, and
2810 @c FIXME: Add reference to (guix profile) documentation when available.
2811 @var{file} must return a @dfn{manifest} object, which is roughly a list
2814 @findex packages->manifest
2816 (use-package-modules guile emacs)
2821 ;; Use a specific package output.
2822 (list guile-2.0 "debug")))
2825 @findex specifications->manifest
2826 In this example we have to know which modules define the @code{emacs}
2827 and @code{guile-2.0} variables to provide the right
2828 @code{use-package-modules} line, which can be cumbersome. We can
2829 instead provide regular package specifications and let
2830 @code{specifications->manifest} look up the corresponding package
2834 (specifications->manifest
2835 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2839 @cindex rolling back
2840 @cindex undoing transactions
2841 @cindex transactions, undoing
2842 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2843 the last transaction.
2845 When combined with options such as @code{--install}, roll back occurs
2846 before any other actions.
2848 When rolling back from the first generation that actually contains
2849 installed packages, the profile is made to point to the @dfn{zeroth
2850 generation}, which contains no files apart from its own metadata.
2852 After having rolled back, installing, removing, or upgrading packages
2853 overwrites previous future generations. Thus, the history of the
2854 generations in a profile is always linear.
2856 @item --switch-generation=@var{pattern}
2857 @itemx -S @var{pattern}
2859 Switch to a particular generation defined by @var{pattern}.
2861 @var{pattern} may be either a generation number or a number prefixed
2862 with ``+'' or ``-''. The latter means: move forward/backward by a
2863 specified number of generations. For example, if you want to return to
2864 the latest generation after @code{--roll-back}, use
2865 @code{--switch-generation=+1}.
2867 The difference between @code{--roll-back} and
2868 @code{--switch-generation=-1} is that @code{--switch-generation} will
2869 not make a zeroth generation, so if a specified generation does not
2870 exist, the current generation will not be changed.
2872 @item --search-paths[=@var{kind}]
2873 @cindex search paths
2874 Report environment variable definitions, in Bash syntax, that may be
2875 needed in order to use the set of installed packages. These environment
2876 variables are used to specify @dfn{search paths} for files used by some
2877 of the installed packages.
2879 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2880 environment variables to be defined so it can look for headers and
2881 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2882 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2883 library are installed in the profile, then @code{--search-paths} will
2884 suggest setting these variables to @code{@var{profile}/include} and
2885 @code{@var{profile}/lib}, respectively.
2887 The typical use case is to define these environment variables in the
2891 $ eval `guix package --search-paths`
2894 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2895 meaning that the returned environment variable definitions will either
2896 be exact settings, or prefixes or suffixes of the current value of these
2897 variables. When omitted, @var{kind} defaults to @code{exact}.
2899 This option can also be used to compute the @emph{combined} search paths
2900 of several profiles. Consider this example:
2903 $ guix package -p foo -i guile
2904 $ guix package -p bar -i guile-json
2905 $ guix package -p foo -p bar --search-paths
2908 The last command above reports about the @code{GUILE_LOAD_PATH}
2909 variable, even though, taken individually, neither @file{foo} nor
2910 @file{bar} would lead to that recommendation.
2913 @item --profile=@var{profile}
2914 @itemx -p @var{profile}
2915 Use @var{profile} instead of the user's default profile.
2917 @var{profile} must be the name of a file that will be created upon
2918 completion. Concretely, @var{profile} will be a mere symbolic link
2919 (``symlink'') pointing to the actual profile where packages are
2923 $ guix install hello -p ~/code/my-profile
2925 $ ~/code/my-profile/bin/hello
2929 All it takes to get rid of the profile is to remove this symlink and its
2930 siblings that point to specific generations:
2933 $ rm ~/code/my-profile ~/code/my-profile-*-link
2936 @item --list-profiles
2937 List all the user's profiles:
2940 $ guix package --list-profiles
2941 /home/charlie/.guix-profile
2942 /home/charlie/code/my-profile
2943 /home/charlie/code/devel-profile
2944 /home/charlie/tmp/test
2947 When running as root, list all the profiles of all the users.
2949 @cindex collisions, in a profile
2950 @cindex colliding packages in profiles
2951 @cindex profile collisions
2952 @item --allow-collisions
2953 Allow colliding packages in the new profile. Use at your own risk!
2955 By default, @command{guix package} reports as an error @dfn{collisions}
2956 in the profile. Collisions happen when two or more different versions
2957 or variants of a given package end up in the profile.
2960 Use the bootstrap Guile to build the profile. This option is only
2961 useful to distribution developers.
2965 In addition to these actions, @command{guix package} supports the
2966 following options to query the current state of a profile, or the
2967 availability of packages:
2971 @item --search=@var{regexp}
2972 @itemx -s @var{regexp}
2973 @cindex searching for packages
2974 List the available packages whose name, synopsis, or description matches
2975 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
2976 Print all the metadata of matching packages in
2977 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
2978 GNU recutils manual}).
2980 This allows specific fields to be extracted using the @command{recsel}
2981 command, for instance:
2984 $ guix package -s malloc | recsel -p name,version,relevance
2998 Similarly, to show the name of all the packages available under the
2999 terms of the GNU@tie{}LGPL version 3:
3002 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3009 It is also possible to refine search results using several @code{-s} flags to
3010 @command{guix package}, or several arguments to @command{guix search}. For
3011 example, the following command returns a list of board games (this time using
3012 the @command{guix search} alias):
3015 $ guix search '\<board\>' game | recsel -p name
3020 If we were to omit @code{-s game}, we would also get software packages
3021 that deal with printed circuit boards; removing the angle brackets
3022 around @code{board} would further add packages that have to do with
3025 And now for a more elaborate example. The following command searches
3026 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3027 libraries, and prints the name and synopsis of the matching packages:
3030 $ guix search crypto library | \
3031 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3035 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3036 information on @dfn{selection expressions} for @code{recsel -e}.
3038 @item --show=@var{package}
3039 Show details about @var{package}, taken from the list of available packages, in
3040 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3044 $ guix package --show=python | recsel -p name,version
3052 You may also specify the full name of a package to only get details about a
3053 specific version of it (this time using the @command{guix show} alias):
3055 $ guix show python@@3.4 | recsel -p name,version
3062 @item --list-installed[=@var{regexp}]
3063 @itemx -I [@var{regexp}]
3064 List the currently installed packages in the specified profile, with the
3065 most recently installed packages shown last. When @var{regexp} is
3066 specified, list only installed packages whose name matches @var{regexp}.
3068 For each installed package, print the following items, separated by
3069 tabs: the package name, its version string, the part of the package that
3070 is installed (for instance, @code{out} for the default output,
3071 @code{include} for its headers, etc.), and the path of this package in
3074 @item --list-available[=@var{regexp}]
3075 @itemx -A [@var{regexp}]
3076 List packages currently available in the distribution for this system
3077 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3078 installed packages whose name matches @var{regexp}.
3080 For each package, print the following items separated by tabs: its name,
3081 its version string, the parts of the package (@pxref{Packages with
3082 Multiple Outputs}), and the source location of its definition.
3084 @item --list-generations[=@var{pattern}]
3085 @itemx -l [@var{pattern}]
3087 Return a list of generations along with their creation dates; for each
3088 generation, show the installed packages, with the most recently
3089 installed packages shown last. Note that the zeroth generation is never
3092 For each installed package, print the following items, separated by
3093 tabs: the name of a package, its version string, the part of the package
3094 that is installed (@pxref{Packages with Multiple Outputs}), and the
3095 location of this package in the store.
3097 When @var{pattern} is used, the command returns only matching
3098 generations. Valid patterns include:
3101 @item @emph{Integers and comma-separated integers}. Both patterns denote
3102 generation numbers. For instance, @code{--list-generations=1} returns
3105 And @code{--list-generations=1,8,2} outputs three generations in the
3106 specified order. Neither spaces nor trailing commas are allowed.
3108 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3109 specified generations and everything in between. Note that the start of
3110 a range must be smaller than its end.
3112 It is also possible to omit the endpoint. For example,
3113 @code{--list-generations=2..}, returns all generations starting from the
3116 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3117 or months by passing an integer along with the first letter of the
3118 duration. For example, @code{--list-generations=20d} lists generations
3119 that are up to 20 days old.
3122 @item --delete-generations[=@var{pattern}]
3123 @itemx -d [@var{pattern}]
3124 When @var{pattern} is omitted, delete all generations except the current
3127 This command accepts the same patterns as @option{--list-generations}.
3128 When @var{pattern} is specified, delete the matching generations. When
3129 @var{pattern} specifies a duration, generations @emph{older} than the
3130 specified duration match. For instance, @code{--delete-generations=1m}
3131 deletes generations that are more than one month old.
3133 If the current generation matches, it is @emph{not} deleted. Also, the
3134 zeroth generation is never deleted.
3136 Note that deleting generations prevents rolling back to them.
3137 Consequently, this command must be used with care.
3141 Finally, since @command{guix package} may actually start build
3142 processes, it supports all the common build options (@pxref{Common Build
3143 Options}). It also supports package transformation options, such as
3144 @option{--with-source} (@pxref{Package Transformation Options}).
3145 However, note that package transformations are lost when upgrading; to
3146 preserve transformations across upgrades, you should define your own
3147 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3148 (@pxref{Defining Packages}).
3151 @section Substitutes
3154 @cindex pre-built binaries
3155 Guix supports transparent source/binary deployment, which means that it
3156 can either build things locally, or download pre-built items from a
3157 server, or both. We call these pre-built items @dfn{substitutes}---they
3158 are substitutes for local build results. In many cases, downloading a
3159 substitute is much faster than building things locally.
3161 Substitutes can be anything resulting from a derivation build
3162 (@pxref{Derivations}). Of course, in the common case, they are
3163 pre-built package binaries, but source tarballs, for instance, which
3164 also result from derivation builds, can be available as substitutes.
3167 * Official Substitute Server:: One particular source of substitutes.
3168 * Substitute Server Authorization:: How to enable or disable substitutes.
3169 * Substitute Authentication:: How Guix verifies substitutes.
3170 * Proxy Settings:: How to get substitutes via proxy.
3171 * Substitution Failure:: What happens when substitution fails.
3172 * On Trusting Binaries:: How can you trust that binary blob?
3175 @node Official Substitute Server
3176 @subsection Official Substitute Server
3179 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3180 that builds packages from Guix continuously for some
3181 architectures, and makes them available as substitutes. This is the
3182 default source of substitutes; it can be overridden by passing the
3183 @option{--substitute-urls} option either to @command{guix-daemon}
3184 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3185 or to client tools such as @command{guix package}
3186 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3189 Substitute URLs can be either HTTP or HTTPS.
3190 HTTPS is recommended because communications are encrypted; conversely,
3191 using HTTP makes all communications visible to an eavesdropper, who
3192 could use the information gathered to determine, for instance, whether
3193 your system has unpatched security vulnerabilities.
3195 Substitutes from the official build farm are enabled by default when
3196 using Guix System (@pxref{GNU Distribution}). However,
3197 they are disabled by default when using Guix on a foreign distribution,
3198 unless you have explicitly enabled them via one of the recommended
3199 installation steps (@pxref{Installation}). The following paragraphs
3200 describe how to enable or disable substitutes for the official build
3201 farm; the same procedure can also be used to enable substitutes for any
3202 other substitute server.
3204 @node Substitute Server Authorization
3205 @subsection Substitute Server Authorization
3208 @cindex substitutes, authorization thereof
3209 @cindex access control list (ACL), for substitutes
3210 @cindex ACL (access control list), for substitutes
3211 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3213 must add its public key to the access control list (ACL) of archive
3214 imports, using the @command{guix archive} command (@pxref{Invoking guix
3215 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3216 be compromised and to serve genuine substitutes.
3218 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3219 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3220 the installation prefix of Guix. If you installed Guix from source,
3221 make sure you checked the GPG signature of
3222 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3223 Then, you can run something like this:
3226 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3229 Once this is in place, the output of a command like @code{guix build}
3230 should change from something like:
3233 $ guix build emacs --dry-run
3234 The following derivations would be built:
3235 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3236 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3237 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3238 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3246 $ guix build emacs --dry-run
3247 112.3 MB would be downloaded:
3248 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3249 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3250 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3251 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3256 This indicates that substitutes from @code{@value{SUBSTITUTE-SERVER}} are usable and
3257 will be downloaded, when possible, for future builds.
3259 @cindex substitutes, how to disable
3260 The substitute mechanism can be disabled globally by running
3261 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3262 guix-daemon}). It can also be disabled temporarily by passing the
3263 @code{--no-substitutes} option to @command{guix package}, @command{guix
3264 build}, and other command-line tools.
3266 @node Substitute Authentication
3267 @subsection Substitute Authentication
3269 @cindex digital signatures
3270 Guix detects and raises an error when attempting to use a substitute
3271 that has been tampered with. Likewise, it ignores substitutes that are
3272 not signed, or that are not signed by one of the keys listed in the ACL.
3274 There is one exception though: if an unauthorized server provides
3275 substitutes that are @emph{bit-for-bit identical} to those provided by
3276 an authorized server, then the unauthorized server becomes eligible for
3277 downloads. For example, assume we have chosen two substitute servers
3281 --substitute-urls="https://a.example.org https://b.example.org"
3285 @cindex reproducible builds
3286 If the ACL contains only the key for @code{b.example.org}, and if
3287 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3288 then Guix will download substitutes from @code{a.example.org} because it
3289 comes first in the list and can be considered a mirror of
3290 @code{b.example.org}. In practice, independent build machines usually
3291 produce the same binaries, thanks to bit-reproducible builds (see
3294 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3295 (in other words, the server is not authenticated), contrary to what
3296 HTTPS clients such as Web browsers usually do. This is because Guix
3297 authenticates substitute information itself, as explained above, which
3298 is what we care about (whereas X.509 certificates are about
3299 authenticating bindings between domain names and public keys.)
3301 @node Proxy Settings
3302 @subsection Proxy Settings
3305 Substitutes are downloaded over HTTP or HTTPS.
3306 The @code{http_proxy} environment
3307 variable can be set in the environment of @command{guix-daemon} and is
3308 honored for downloads of substitutes. Note that the value of
3309 @code{http_proxy} in the environment where @command{guix build},
3310 @command{guix package}, and other client commands are run has
3311 @emph{absolutely no effect}.
3313 @node Substitution Failure
3314 @subsection Substitution Failure
3316 Even when a substitute for a derivation is available, sometimes the
3317 substitution attempt will fail. This can happen for a variety of
3318 reasons: the substitute server might be offline, the substitute may
3319 recently have been deleted, the connection might have been interrupted,
3322 When substitutes are enabled and a substitute for a derivation is
3323 available, but the substitution attempt fails, Guix will attempt to
3324 build the derivation locally depending on whether or not
3325 @code{--fallback} was given (@pxref{fallback-option,, common build
3326 option @code{--fallback}}). Specifically, if @code{--fallback} was
3327 omitted, then no local build will be performed, and the derivation is
3328 considered to have failed. However, if @code{--fallback} was given,
3329 then Guix will attempt to build the derivation locally, and the success
3330 or failure of the derivation depends on the success or failure of the
3331 local build. Note that when substitutes are disabled or no substitute
3332 is available for the derivation in question, a local build will
3333 @emph{always} be performed, regardless of whether or not
3334 @code{--fallback} was given.
3336 To get an idea of how many substitutes are available right now, you can
3337 try running the @command{guix weather} command (@pxref{Invoking guix
3338 weather}). This command provides statistics on the substitutes provided
3341 @node On Trusting Binaries
3342 @subsection On Trusting Binaries
3344 @cindex trust, of pre-built binaries
3345 Today, each individual's control over their own computing is at the
3346 mercy of institutions, corporations, and groups with enough power and
3347 determination to subvert the computing infrastructure and exploit its
3348 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3349 convenient, we encourage users to also build on their own, or even run
3350 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3351 interesting target. One way to help is by publishing the software you
3352 build using @command{guix publish} so that others have one more choice
3353 of server to download substitutes from (@pxref{Invoking guix publish}).
3355 Guix has the foundations to maximize build reproducibility
3356 (@pxref{Features}). In most cases, independent builds of a given
3357 package or derivation should yield bit-identical results. Thus, through
3358 a diverse set of independent package builds, we can strengthen the
3359 integrity of our systems. The @command{guix challenge} command aims to
3360 help users assess substitute servers, and to assist developers in
3361 finding out about non-deterministic package builds (@pxref{Invoking guix
3362 challenge}). Similarly, the @option{--check} option of @command{guix
3363 build} allows users to check whether previously-installed substitutes
3364 are genuine by rebuilding them locally (@pxref{build-check,
3365 @command{guix build --check}}).
3367 In the future, we want Guix to have support to publish and retrieve
3368 binaries to/from other users, in a peer-to-peer fashion. If you would
3369 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3371 @node Packages with Multiple Outputs
3372 @section Packages with Multiple Outputs
3374 @cindex multiple-output packages
3375 @cindex package outputs
3378 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3379 source package leads to exactly one directory in the store. When running
3380 @command{guix install glibc}, one installs the default output of the
3381 GNU libc package; the default output is called @code{out}, but its name
3382 can be omitted as shown in this command. In this particular case, the
3383 default output of @code{glibc} contains all the C header files, shared
3384 libraries, static libraries, Info documentation, and other supporting
3387 Sometimes it is more appropriate to separate the various types of files
3388 produced from a single source package into separate outputs. For
3389 instance, the GLib C library (used by GTK+ and related packages)
3390 installs more than 20 MiB of reference documentation as HTML pages.
3391 To save space for users who do not need it, the documentation goes to a
3392 separate output, called @code{doc}. To install the main GLib output,
3393 which contains everything but the documentation, one would run:
3399 @cindex documentation
3400 The command to install its documentation is:
3403 guix install glib:doc
3406 Some packages install programs with different ``dependency footprints''.
3407 For instance, the WordNet package installs both command-line tools and
3408 graphical user interfaces (GUIs). The former depend solely on the C
3409 library, whereas the latter depend on Tcl/Tk and the underlying X
3410 libraries. In this case, we leave the command-line tools in the default
3411 output, whereas the GUIs are in a separate output. This allows users
3412 who do not need the GUIs to save space. The @command{guix size} command
3413 can help find out about such situations (@pxref{Invoking guix size}).
3414 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3416 There are several such multiple-output packages in the GNU distribution.
3417 Other conventional output names include @code{lib} for libraries and
3418 possibly header files, @code{bin} for stand-alone programs, and
3419 @code{debug} for debugging information (@pxref{Installing Debugging
3420 Files}). The outputs of a packages are listed in the third column of
3421 the output of @command{guix package --list-available} (@pxref{Invoking
3425 @node Invoking guix gc
3426 @section Invoking @command{guix gc}
3428 @cindex garbage collector
3430 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3431 The @command{guix gc} command allows users to explicitly run the garbage
3432 collector to reclaim space from the @file{/gnu/store} directory. It is
3433 the @emph{only} way to remove files from @file{/gnu/store}---removing
3434 files or directories manually may break it beyond repair!
3437 @cindex garbage collector roots
3438 The garbage collector has a set of known @dfn{roots}: any file under
3439 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3440 cannot be deleted; any other file is considered @dfn{dead} and may be
3441 deleted. The set of garbage collector roots (``GC roots'' for short)
3442 includes default user profiles; by default, the symlinks under
3443 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3444 added with @command{guix build --root}, for example (@pxref{Invoking
3445 guix build}). The @command{guix gc --list-roots} command lists them.
3447 Prior to running @code{guix gc --collect-garbage} to make space, it is
3448 often useful to remove old generations from user profiles; that way, old
3449 package builds referenced by those generations can be reclaimed. This
3450 is achieved by running @code{guix package --delete-generations}
3451 (@pxref{Invoking guix package}).
3453 Our recommendation is to run a garbage collection periodically, or when
3454 you are short on disk space. For instance, to guarantee that at least
3455 5@tie{}GB are available on your disk, simply run:
3461 It is perfectly safe to run as a non-interactive periodic job
3462 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3463 Running @command{guix gc} with no arguments will collect as
3464 much garbage as it can, but that is often inconvenient: you may find
3465 yourself having to rebuild or re-download software that is ``dead'' from
3466 the GC viewpoint but that is necessary to build other pieces of
3467 software---e.g., the compiler tool chain.
3469 The @command{guix gc} command has three modes of operation: it can be
3470 used to garbage-collect any dead files (the default), to delete specific
3471 files (the @code{--delete} option), to print garbage-collector
3472 information, or for more advanced queries. The garbage collection
3473 options are as follows:
3476 @item --collect-garbage[=@var{min}]
3477 @itemx -C [@var{min}]
3478 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3479 sub-directories. This is the default operation when no option is
3482 When @var{min} is given, stop once @var{min} bytes have been collected.
3483 @var{min} may be a number of bytes, or it may include a unit as a
3484 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3485 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3487 When @var{min} is omitted, collect all the garbage.
3489 @item --free-space=@var{free}
3490 @itemx -F @var{free}
3491 Collect garbage until @var{free} space is available under
3492 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3493 as @code{500MiB}, as described above.
3495 When @var{free} or more is already available in @file{/gnu/store}, do
3496 nothing and exit immediately.
3498 @item --delete-generations[=@var{duration}]
3499 @itemx -d [@var{duration}]
3500 Before starting the garbage collection process, delete all the generations
3501 older than @var{duration}, for all the user profiles; when run as root, this
3502 applies to all the profiles @emph{of all the users}.
3504 For example, this command deletes all the generations of all your profiles
3505 that are older than 2 months (except generations that are current), and then
3506 proceeds to free space until at least 10 GiB are available:
3509 guix gc -d 2m -F 10G
3514 Attempt to delete all the store files and directories specified as
3515 arguments. This fails if some of the files are not in the store, or if
3516 they are still live.
3518 @item --list-failures
3519 List store items corresponding to cached build failures.
3521 This prints nothing unless the daemon was started with
3522 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3523 @option{--cache-failures}}).
3526 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3530 List store items in use by currently running processes. These store
3531 items are effectively considered GC roots: they cannot be deleted.
3533 @item --clear-failures
3534 Remove the specified store items from the failed-build cache.
3536 Again, this option only makes sense when the daemon is started with
3537 @option{--cache-failures}. Otherwise, it does nothing.
3540 Show the list of dead files and directories still present in the
3541 store---i.e., files and directories no longer reachable from any root.
3544 Show the list of live store files and directories.
3548 In addition, the references among existing store files can be queried:
3554 @cindex package dependencies
3555 List the references (respectively, the referrers) of store files given
3561 List the requisites of the store files passed as arguments. Requisites
3562 include the store files themselves, their references, and the references
3563 of these, recursively. In other words, the returned list is the
3564 @dfn{transitive closure} of the store files.
3566 @xref{Invoking guix size}, for a tool to profile the size of the closure
3567 of an element. @xref{Invoking guix graph}, for a tool to visualize
3568 the graph of references.
3572 Return the derivation(s) leading to the given store items
3573 (@pxref{Derivations}).
3575 For example, this command:
3578 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3582 returns the @file{.drv} file(s) leading to the @code{emacs} package
3583 installed in your profile.
3585 Note that there may be zero matching @file{.drv} files, for instance
3586 because these files have been garbage-collected. There can also be more
3587 than one matching @file{.drv} due to fixed-output derivations.
3590 Lastly, the following options allow you to check the integrity of the
3591 store and to control disk usage.
3595 @item --verify[=@var{options}]
3596 @cindex integrity, of the store
3597 @cindex integrity checking
3598 Verify the integrity of the store.
3600 By default, make sure that all the store items marked as valid in the
3601 database of the daemon actually exist in @file{/gnu/store}.
3603 When provided, @var{options} must be a comma-separated list containing one
3604 or more of @code{contents} and @code{repair}.
3606 When passing @option{--verify=contents}, the daemon computes the
3607 content hash of each store item and compares it against its hash in the
3608 database. Hash mismatches are reported as data corruptions. Because it
3609 traverses @emph{all the files in the store}, this command can take a
3610 long time, especially on systems with a slow disk drive.
3612 @cindex repairing the store
3613 @cindex corruption, recovering from
3614 Using @option{--verify=repair} or @option{--verify=contents,repair}
3615 causes the daemon to try to repair corrupt store items by fetching
3616 substitutes for them (@pxref{Substitutes}). Because repairing is not
3617 atomic, and thus potentially dangerous, it is available only to the
3618 system administrator. A lightweight alternative, when you know exactly
3619 which items in the store are corrupt, is @command{guix build --repair}
3620 (@pxref{Invoking guix build}).
3623 @cindex deduplication
3624 Optimize the store by hard-linking identical files---this is
3625 @dfn{deduplication}.
3627 The daemon performs deduplication after each successful build or archive
3628 import, unless it was started with @code{--disable-deduplication}
3629 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3630 this option is primarily useful when the daemon was running with
3631 @code{--disable-deduplication}.
3635 @node Invoking guix pull
3636 @section Invoking @command{guix pull}
3638 @cindex upgrading Guix
3639 @cindex updating Guix
3640 @cindex @command{guix pull}
3642 Packages are installed or upgraded to the latest version available in
3643 the distribution currently available on your local machine. To update
3644 that distribution, along with the Guix tools, you must run @command{guix
3645 pull}: the command downloads the latest Guix source code and package
3646 descriptions, and deploys it. Source code is downloaded from a
3647 @uref{https://git-scm.com, Git} repository, by default the official
3648 GNU@tie{}Guix repository, though this can be customized.
3650 On completion, @command{guix package} will use packages and package
3651 versions from this just-retrieved copy of Guix. Not only that, but all
3652 the Guix commands and Scheme modules will also be taken from that latest
3653 version. New @command{guix} sub-commands added by the update also
3656 Any user can update their Guix copy using @command{guix pull}, and the
3657 effect is limited to the user who ran @command{guix pull}. For
3658 instance, when user @code{root} runs @command{guix pull}, this has no
3659 effect on the version of Guix that user @code{alice} sees, and vice
3662 The result of running @command{guix pull} is a @dfn{profile} available
3663 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3664 make sure to add it to the beginning of your search path so that you use
3665 the latest version, and similarly for the Info manual
3666 (@pxref{Documentation}):
3669 export PATH="$HOME/.config/guix/current/bin:$PATH"
3670 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3673 The @code{--list-generations} or @code{-l} option lists past generations
3674 produced by @command{guix pull}, along with details about their provenance:
3678 Generation 1 Jun 10 2018 00:18:18
3680 repository URL: https://git.savannah.gnu.org/git/guix.git
3681 branch: origin/master
3682 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3684 Generation 2 Jun 11 2018 11:02:49
3686 repository URL: https://git.savannah.gnu.org/git/guix.git
3687 branch: origin/master
3688 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3689 2 new packages: keepalived, libnfnetlink
3690 6 packages upgraded: emacs-nix-mode@@2.0.4,
3691 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3692 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3694 Generation 3 Jun 13 2018 23:31:07 (current)
3696 repository URL: https://git.savannah.gnu.org/git/guix.git
3697 branch: origin/master
3698 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3699 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3700 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3703 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3704 describe the current status of Guix.
3706 This @code{~/.config/guix/current} profile works exactly like the profiles
3707 created by @command{guix package} (@pxref{Invoking guix package}). That
3708 is, you can list generations, roll back to the previous
3709 generation---i.e., the previous Guix---and so on:
3712 $ guix pull --roll-back
3713 switched from generation 3 to 2
3714 $ guix pull --delete-generations=1
3715 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3718 You can also use @command{guix package} (@pxref{Invoking guix package})
3719 to manage the profile by naming it explicitly:
3721 $ guix package -p ~/.config/guix/current --roll-back
3722 switched from generation 3 to 2
3723 $ guix package -p ~/.config/guix/current --delete-generations=1
3724 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3727 The @command{guix pull} command is usually invoked with no arguments,
3728 but it supports the following options:
3731 @item --url=@var{url}
3732 @itemx --commit=@var{commit}
3733 @itemx --branch=@var{branch}
3734 Download code for the @code{guix} channel from the specified @var{url}, at the
3735 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3736 string), or @var{branch}.
3738 @cindex @file{channels.scm}, configuration file
3739 @cindex configuration file for channels
3740 These options are provided for convenience, but you can also specify your
3741 configuration in the @file{~/.config/guix/channels.scm} file or using the
3742 @option{--channels} option (see below).
3744 @item --channels=@var{file}
3745 @itemx -C @var{file}
3746 Read the list of channels from @var{file} instead of
3747 @file{~/.config/guix/channels.scm}. @var{file} must contain Scheme code that
3748 evaluates to a list of channel objects. @xref{Channels}, for more
3751 @cindex channel news
3754 Display the list of packages added or upgraded since the previous
3755 generation, as well as, occasionally, news written by channel authors
3756 for their users (@pxref{Channels, Writing Channel News}).
3758 The package information is the same as displayed upon @command{guix
3759 pull} completion, but without ellipses; it is also similar to the output
3760 of @command{guix pull -l} for the last generation (see below).
3762 @item --list-generations[=@var{pattern}]
3763 @itemx -l [@var{pattern}]
3764 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3765 is provided, the subset of generations that match @var{pattern}.
3766 The syntax of @var{pattern} is the same as with @code{guix package
3767 --list-generations} (@pxref{Invoking guix package}).
3770 @cindex rolling back
3771 @cindex undoing transactions
3772 @cindex transactions, undoing
3773 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
3774 undo the last transaction.
3776 @item --switch-generation=@var{pattern}
3777 @itemx -S @var{pattern}
3779 Switch to a particular generation defined by @var{pattern}.
3781 @var{pattern} may be either a generation number or a number prefixed
3782 with ``+'' or ``-''. The latter means: move forward/backward by a
3783 specified number of generations. For example, if you want to return to
3784 the latest generation after @code{--roll-back}, use
3785 @code{--switch-generation=+1}.
3787 @item --delete-generations[=@var{pattern}]
3788 @itemx -d [@var{pattern}]
3789 When @var{pattern} is omitted, delete all generations except the current
3792 This command accepts the same patterns as @option{--list-generations}.
3793 When @var{pattern} is specified, delete the matching generations. When
3794 @var{pattern} specifies a duration, generations @emph{older} than the
3795 specified duration match. For instance, @code{--delete-generations=1m}
3796 deletes generations that are more than one month old.
3798 If the current generation matches, it is @emph{not} deleted.
3800 Note that deleting generations prevents rolling back to them.
3801 Consequently, this command must be used with care.
3803 @xref{Invoking guix describe}, for a way to display information about the
3804 current generation only.
3806 @item --profile=@var{profile}
3807 @itemx -p @var{profile}
3808 Use @var{profile} instead of @file{~/.config/guix/current}.
3812 Show which channel commit(s) would be used and what would be built or
3813 substituted but do not actually do it.
3815 @item --system=@var{system}
3816 @itemx -s @var{system}
3817 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3818 the system type of the build host.
3821 Produce verbose output, writing build logs to the standard error output.
3824 Use the bootstrap Guile to build the latest Guix. This option is only
3825 useful to Guix developers.
3828 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3829 repository and branch to pull from, as well as @emph{additional} repositories
3830 containing package modules that should be deployed. @xref{Channels}, for more
3833 In addition, @command{guix pull} supports all the common build options
3834 (@pxref{Common Build Options}).
3840 @cindex @file{channels.scm}, configuration file
3841 @cindex configuration file for channels
3842 @cindex @command{guix pull}, configuration file
3843 @cindex configuration of @command{guix pull}
3844 Guix and its package collection are updated by running @command{guix pull}
3845 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3846 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3847 customized by defining @dfn{channels} in the
3848 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3849 of a Git repository to be deployed, and @command{guix pull} can be instructed
3850 to pull from one or more channels. In other words, channels can be used to
3851 @emph{customize} and to @emph{extend} Guix, as we will see below.
3853 @subsection Using a Custom Guix Channel
3855 The channel called @code{guix} specifies where Guix itself---its command-line
3856 tools as well as its package collection---should be downloaded. For instance,
3857 suppose you want to update from your own copy of the Guix repository at
3858 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3859 write in @code{~/.config/guix/channels.scm} this specification:
3862 ;; Tell 'guix pull' to use my own repo.
3865 (url "https://example.org/my-guix.git")
3866 (branch "super-hacks")))
3870 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3871 branch of the repository at @code{example.org}.
3873 @subsection Specifying Additional Channels
3875 @cindex extending the package collection (channels)
3876 @cindex personal packages (channels)
3877 @cindex channels, for personal packages
3878 You can also specify @emph{additional channels} to pull from. Let's say you
3879 have a bunch of custom package variants or personal packages that you think
3880 would make little sense to contribute to the Guix project, but would like to
3881 have these packages transparently available to you at the command line. You
3882 would first write modules containing those package definitions (@pxref{Package
3883 Modules}), maintain them in a Git repository, and then you and anyone else can
3884 use it as an additional channel to get packages from. Neat, no?
3886 @c What follows stems from discussions at
3887 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3888 @c earlier discussions on guix-devel@gnu.org.
3890 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3891 publish your personal channel to the world, we would like to share a few words
3896 Before publishing a channel, please consider contributing your package
3897 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3898 to free software of all sorts, and packages in Guix proper are readily
3899 available to all Guix users and benefit from the project's quality assurance
3903 When you maintain package definitions outside Guix, we, Guix developers,
3904 consider that @emph{the compatibility burden is on you}. Remember that
3905 package modules and package definitions are just Scheme code that uses various
3906 programming interfaces (APIs). We want to remain free to change these APIs to
3907 keep improving Guix, possibly in ways that break your channel. We never
3908 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
3912 Corollary: if you're using an external channel and that channel breaks, please
3913 @emph{report the issue to the channel authors}, not to the Guix project.
3916 You've been warned! Having said this, we believe external channels are a
3917 practical way to exert your freedom to augment Guix' package collection and to
3918 share your improvements, which are basic tenets of
3919 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
3920 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
3923 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
3924 @command{guix pull} to pull from it @emph{in addition} to the default Guix
3927 @vindex %default-channels
3929 ;; Add my personal packages to those Guix provides.
3931 (name 'my-personal-packages)
3932 (url "https://example.org/personal-packages.git"))
3937 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
3938 add a channel the list of channels that the variable @code{%default-channels}
3939 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
3940 Manual}). With this file in place, @command{guix pull} builds not only Guix
3941 but also the package modules from your own repository. The result in
3942 @file{~/.config/guix/current} is the union of Guix with your own package
3946 $ guix pull --list-generations
3948 Generation 19 Aug 27 2018 16:20:48
3950 repository URL: https://git.savannah.gnu.org/git/guix.git
3952 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
3953 my-personal-packages dd3df5e
3954 repository URL: https://example.org/personal-packages.git
3956 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
3957 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
3958 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
3962 The output of @command{guix pull} above shows that Generation@tie{}19 includes
3963 both Guix and packages from the @code{my-personal-packages} channel. Among
3964 the new and upgraded packages that are listed, some like @code{my-gimp} and
3965 @code{my-emacs-with-cool-features} might come from
3966 @code{my-personal-packages}, while others come from the Guix default channel.
3968 To create a channel, create a Git repository containing your own package
3969 modules and make it available. The repository can contain anything, but a
3970 useful channel will contain Guile modules that export packages. Once you
3971 start using a channel, Guix will behave as if the root directory of that
3972 channel's Git repository has been added to the Guile load path (@pxref{Load
3973 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
3974 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
3975 module, then the module will be available under the name @code{(my-packages
3976 my-tools)}, and you will be able to use it like any other module
3977 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
3979 @cindex dependencies, channels
3980 @cindex meta-data, channels
3981 @subsection Declaring Channel Dependencies
3983 Channel authors may decide to augment a package collection provided by other
3984 channels. They can declare their channel to be dependent on other channels in
3985 a meta-data file @file{.guix-channel}, which is to be placed in the root of
3986 the channel repository.
3988 The meta-data file should contain a simple S-expression like this:
3995 (name some-collection)
3996 (url "https://example.org/first-collection.git"))
3998 (name some-other-collection)
3999 (url "https://example.org/second-collection.git")
4000 (branch "testing"))))
4003 In the above example this channel is declared to depend on two other channels,
4004 which will both be fetched automatically. The modules provided by the channel
4005 will be compiled in an environment where the modules of all these declared
4006 channels are available.
4008 For the sake of reliability and maintainability, you should avoid dependencies
4009 on channels that you don't control, and you should aim to keep the number of
4010 dependencies to a minimum.
4012 @cindex subdirectory, channels
4013 @subsection Package Modules in a Sub-directory
4015 As a channel author, you may want to keep your channel modules in a
4016 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4017 add a meta-data file @file{.guix-channel} that contains:
4025 @cindex news, for channels
4026 @subsection Writing Channel News
4028 Channel authors may occasionally want to communicate to their users
4029 information about important changes in the channel. You'd send them all
4030 an email, but that's not convenient.
4032 Instead, channels can provide a @dfn{news file}; when the channel users
4033 run @command{guix pull}, that news file is automatically read and
4034 @command{guix pull --news} can display the announcements that correspond
4035 to the new commits that have been pulled, if any.
4037 To do that, channel authors must first declare the name of the news file
4038 in their @file{.guix-channel} file:
4043 (news-file "etc/news.txt"))
4046 The news file itself, @file{etc/news.txt} in this example, must look
4047 something like this:
4052 (entry (tag "the-bug-fix")
4053 (title (en "Fixed terrible bug")
4055 (body (en "@@emph@{Good news@}! It's fixed!")
4056 (eo "Certe ĝi pli bone funkcias nun!")))
4057 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4058 (title (en "Added a great package")
4059 (ca "Què vol dir guix?"))
4060 (body (en "Don't miss the @@code@{hello@} package!"))))
4063 The file consists of a list of @dfn{news entries}. Each entry is
4064 associated with a commit or tag: it describes changes made in this
4065 commit, possibly in preceding commits as well. Users see entries only
4066 the first time they obtain the commit the entry refers to.
4068 The @code{title} field should be a one-line summary while @code{body}
4069 can be arbitrarily long, and both can contain Texinfo markup
4070 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4071 a list of language tag/message tuples, which allows @command{guix pull}
4072 to display news in the language that corresponds to the user's locale.
4074 If you want to translate news using a gettext-based workflow, you can
4075 extract translatable strings with @command{xgettext} (@pxref{xgettext
4076 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4077 you write news entries in English first, the command below creates a PO
4078 file containing the strings to translate:
4081 xgettext -o news.po -l scheme -ken etc/news.scm
4084 To sum up, yes, you could use your channel as a blog. But beware, this
4085 is @emph{not quite} what your users might expect.
4087 @subsection Replicating Guix
4089 @cindex pinning, channels
4090 @cindex replicating Guix
4091 @cindex reproducibility, of Guix
4092 The @command{guix pull --list-generations} output above shows precisely which
4093 commits were used to build this instance of Guix. We can thus replicate it,
4094 say, on another machine, by providing a channel specification in
4095 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4098 ;; Deploy specific commits of my channels of interest.
4101 (url "https://git.savannah.gnu.org/git/guix.git")
4102 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
4104 (name 'my-personal-packages)
4105 (url "https://example.org/personal-packages.git")
4106 (branch "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4109 The @command{guix describe --format=channels} command can even generate this
4110 list of channels directly (@pxref{Invoking guix describe}).
4112 At this point the two machines run the @emph{exact same Guix}, with access to
4113 the @emph{exact same packages}. The output of @command{guix build gimp} on
4114 one machine will be exactly the same, bit for bit, as the output of the same
4115 command on the other machine. It also means both machines have access to all
4116 the source code of Guix and, transitively, to all the source code of every
4119 This gives you super powers, allowing you to track the provenance of binary
4120 artifacts with very fine grain, and to reproduce software environments at
4121 will---some sort of ``meta reproducibility'' capabilities, if you will.
4122 @xref{Inferiors}, for another way to take advantage of these super powers.
4127 @c TODO: Remove this once we're more confident about API stability.
4129 The functionality described here is a ``technology preview'' as of version
4130 @value{VERSION}. As such, the interface is subject to change.
4134 @cindex composition of Guix revisions
4135 Sometimes you might need to mix packages from the revision of Guix you're
4136 currently running with packages available in a different revision of Guix.
4137 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4138 revisions in arbitrary ways.
4140 @cindex inferior packages
4141 Technically, an ``inferior'' is essentially a separate Guix process connected
4142 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4143 @code{(guix inferior)} module allows you to create inferiors and to
4144 communicate with them. It also provides a high-level interface to browse and
4145 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4147 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4148 to interact with a separate revision of Guix. For example, let's assume you
4149 want to install in your profile the current @code{guile} package, along with
4150 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4151 because the newer @code{guile-json} has an incompatible API and you want to
4152 run your code against the old API@. To do that, you could write a manifest for
4153 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4154 manifest, you would create an inferior for that old Guix revision you care
4155 about, and you would look up the @code{guile-json} package in the inferior:
4158 (use-modules (guix inferior) (guix channels)
4159 (srfi srfi-1)) ;for 'first'
4162 ;; This is the old revision from which we want to
4163 ;; extract guile-json.
4166 (url "https://git.savannah.gnu.org/git/guix.git")
4168 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4171 ;; An inferior representing the above revision.
4172 (inferior-for-channels channels))
4174 ;; Now create a manifest with the current "guile" package
4175 ;; and the old "guile-json" package.
4177 (list (first (lookup-inferior-packages inferior "guile-json"))
4178 (specification->package "guile")))
4181 On its first run, @command{guix package --manifest} might have to build the
4182 channel you specified before it can create the inferior; subsequent runs will
4183 be much faster because the Guix revision will be cached.
4185 The @code{(guix inferior)} module provides the following procedures to open an
4188 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4189 [#:cache-directory] [#:ttl]
4190 Return an inferior for @var{channels}, a list of channels. Use the cache at
4191 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4192 This procedure opens a new connection to the build daemon.
4194 As a side effect, this procedure may build or substitute binaries for
4195 @var{channels}, which can take time.
4198 @deffn {Scheme Procedure} open-inferior @var{directory} @
4199 [#:command "bin/guix"]
4200 Open the inferior Guix in @var{directory}, running
4201 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4202 the inferior could not be launched.
4205 @cindex inferior packages
4206 The procedures listed below allow you to obtain and manipulate inferior
4209 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4210 Return the list of packages known to @var{inferior}.
4213 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4215 Return the sorted list of inferior packages matching @var{name} in
4216 @var{inferior}, with highest version numbers first. If @var{version} is true,
4217 return only packages with a version number prefixed by @var{version}.
4220 @deffn {Scheme Procedure} inferior-package? @var{obj}
4221 Return true if @var{obj} is an inferior package.
4224 @deffn {Scheme Procedure} inferior-package-name @var{package}
4225 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4226 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4227 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4228 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4229 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4230 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4231 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4232 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4233 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4234 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4235 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4236 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4237 These procedures are the counterpart of package record accessors
4238 (@pxref{package Reference}). Most of them work by querying the inferior
4239 @var{package} comes from, so the inferior must still be live when you call
4243 Inferior packages can be used transparently like any other package or
4244 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4245 transparently handled by the @code{packages->manifest} procedure, which is
4246 commonly use in manifests (@pxref{Invoking guix package, the
4247 @option{--manifest} option of @command{guix package}}). Thus you can insert
4248 an inferior package pretty much anywhere you would insert a regular package:
4249 in manifests, in the @code{packages} field of your @code{operating-system}
4250 declaration, and so on.
4252 @node Invoking guix describe
4253 @section Invoking @command{guix describe}
4255 @cindex reproducibility
4256 @cindex replicating Guix
4257 Often you may want to answer questions like: ``Which revision of Guix am I
4258 using?'' or ``Which channels am I using?'' This is useful information in many
4259 situations: if you want to @emph{replicate} an environment on a different
4260 machine or user account, if you want to report a bug or to determine what
4261 change in the channels you are using caused it, or if you want to record your
4262 system state for reproducibility purposes. The @command{guix describe}
4263 command answers these questions.
4265 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4266 displays the channel(s) that it was built from, including their repository URL
4267 and commit IDs (@pxref{Channels}):
4271 Generation 10 Sep 03 2018 17:32:44 (current)
4273 repository URL: https://git.savannah.gnu.org/git/guix.git
4275 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4278 If you're familiar with the Git version control system, this is similar in
4279 spirit to @command{git describe}; the output is also similar to that of
4280 @command{guix pull --list-generations}, but limited to the current generation
4281 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4282 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4283 information is all it takes to describe the revision of Guix you're using, and
4284 also to replicate it.
4286 To make it easier to replicate Guix, @command{guix describe} can also be asked
4287 to return a list of channels instead of the human-readable description above:
4290 $ guix describe -f channels
4293 (url "https://git.savannah.gnu.org/git/guix.git")
4295 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4299 You can save this to a file and feed it to @command{guix pull -C} on some
4300 other machine or at a later point in time, which will instantiate @emph{this
4301 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4302 From there on, since you're able to deploy the same revision of Guix, you can
4303 just as well @emph{replicate a complete software environment}. We humbly
4304 think that this is @emph{awesome}, and we hope you'll like it too!
4306 The details of the options supported by @command{guix describe} are as
4310 @item --format=@var{format}
4311 @itemx -f @var{format}
4312 Produce output in the specified @var{format}, one of:
4316 produce human-readable output;
4318 produce a list of channel specifications that can be passed to @command{guix
4319 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4323 produce a list of channel specifications in JSON format;
4325 produce a list of channel specifications in Recutils format.
4328 @item --profile=@var{profile}
4329 @itemx -p @var{profile}
4330 Display information about @var{profile}.
4333 @node Invoking guix archive
4334 @section Invoking @command{guix archive}
4336 @cindex @command{guix archive}
4338 The @command{guix archive} command allows users to @dfn{export} files
4339 from the store into a single archive, and to later @dfn{import} them on
4340 a machine that runs Guix.
4341 In particular, it allows store files to be transferred from one machine
4342 to the store on another machine.
4345 If you're looking for a way to produce archives in a format suitable for
4346 tools other than Guix, @pxref{Invoking guix pack}.
4349 @cindex exporting store items
4350 To export store files as an archive to standard output, run:
4353 guix archive --export @var{options} @var{specifications}...
4356 @var{specifications} may be either store file names or package
4357 specifications, as for @command{guix package} (@pxref{Invoking guix
4358 package}). For instance, the following command creates an archive
4359 containing the @code{gui} output of the @code{git} package and the main
4360 output of @code{emacs}:
4363 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4366 If the specified packages are not built yet, @command{guix archive}
4367 automatically builds them. The build process may be controlled with the
4368 common build options (@pxref{Common Build Options}).
4370 To transfer the @code{emacs} package to a machine connected over SSH,
4374 guix archive --export -r emacs | ssh the-machine guix archive --import
4378 Similarly, a complete user profile may be transferred from one machine
4379 to another like this:
4382 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4383 ssh the-machine guix archive --import
4387 However, note that, in both examples, all of @code{emacs} and the
4388 profile as well as all of their dependencies are transferred (due to
4389 @code{-r}), regardless of what is already available in the store on the
4390 target machine. The @code{--missing} option can help figure out which
4391 items are missing from the target store. The @command{guix copy}
4392 command simplifies and optimizes this whole process, so this is probably
4393 what you should use in this case (@pxref{Invoking guix copy}).
4395 @cindex nar, archive format
4396 @cindex normalized archive (nar)
4397 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4398 comparable in spirit to `tar', but with differences
4399 that make it more appropriate for our purposes. First, rather than
4400 recording all Unix metadata for each file, the nar format only mentions
4401 the file type (regular, directory, or symbolic link); Unix permissions
4402 and owner/group are dismissed. Second, the order in which directory
4403 entries are stored always follows the order of file names according to
4404 the C locale collation order. This makes archive production fully
4407 When exporting, the daemon digitally signs the contents of the archive,
4408 and that digital signature is appended. When importing, the daemon
4409 verifies the signature and rejects the import in case of an invalid
4410 signature or if the signing key is not authorized.
4411 @c FIXME: Add xref to daemon doc about signatures.
4413 The main options are:
4417 Export the specified store files or packages (see below.) Write the
4418 resulting archive to the standard output.
4420 Dependencies are @emph{not} included in the output, unless
4421 @code{--recursive} is passed.
4425 When combined with @code{--export}, this instructs @command{guix
4426 archive} to include dependencies of the given items in the archive.
4427 Thus, the resulting archive is self-contained: it contains the closure
4428 of the exported store items.
4431 Read an archive from the standard input, and import the files listed
4432 therein into the store. Abort if the archive has an invalid digital
4433 signature, or if it is signed by a public key not among the authorized
4434 keys (see @code{--authorize} below.)
4437 Read a list of store file names from the standard input, one per line,
4438 and write on the standard output the subset of these files missing from
4441 @item --generate-key[=@var{parameters}]
4442 @cindex signing, archives
4443 Generate a new key pair for the daemon. This is a prerequisite before
4444 archives can be exported with @code{--export}. Note that this operation
4445 usually takes time, because it needs to gather enough entropy to
4446 generate the key pair.
4448 The generated key pair is typically stored under @file{/etc/guix}, in
4449 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4450 key, which must be kept secret.) When @var{parameters} is omitted,
4451 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4452 versions before 1.6.0, it is a 4096-bit RSA key.
4453 Alternatively, @var{parameters} can specify
4454 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4455 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4456 Libgcrypt Reference Manual}).
4459 @cindex authorizing, archives
4460 Authorize imports signed by the public key passed on standard input.
4461 The public key must be in ``s-expression advanced format''---i.e., the
4462 same format as the @file{signing-key.pub} file.
4464 The list of authorized keys is kept in the human-editable file
4465 @file{/etc/guix/acl}. The file contains
4466 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4467 s-expressions''} and is structured as an access-control list in the
4468 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4471 @item --extract=@var{directory}
4472 @itemx -x @var{directory}
4473 Read a single-item archive as served by substitute servers
4474 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4475 low-level operation needed in only very narrow use cases; see below.
4477 For example, the following command extracts the substitute for Emacs
4478 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4482 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-emacs-24.5 \
4483 | bunzip2 | guix archive -x /tmp/emacs
4486 Single-item archives are different from multiple-item archives produced
4487 by @command{guix archive --export}; they contain a single store item,
4488 and they do @emph{not} embed a signature. Thus this operation does
4489 @emph{no} signature verification and its output should be considered
4492 The primary purpose of this operation is to facilitate inspection of
4493 archive contents coming from possibly untrusted substitute servers.
4498 @c *********************************************************************
4500 @chapter Development
4502 @cindex software development
4503 If you are a software developer, Guix provides tools that you should find
4504 helpful---independently of the language you're developing in. This is what
4505 this chapter is about.
4507 The @command{guix environment} command provides a convenient way to set up
4508 @dfn{development environments} containing all the dependencies and tools
4509 necessary to work on the software package of your choice. The @command{guix
4510 pack} command allows you to create @dfn{application bundles} that can be
4511 easily distributed to users who do not run Guix.
4514 * Invoking guix environment:: Setting up development environments.
4515 * Invoking guix pack:: Creating software bundles.
4518 @node Invoking guix environment
4519 @section Invoking @command{guix environment}
4521 @cindex reproducible build environments
4522 @cindex development environments
4523 @cindex @command{guix environment}
4524 @cindex environment, package build environment
4525 The purpose of @command{guix environment} is to assist hackers in
4526 creating reproducible development environments without polluting their
4527 package profile. The @command{guix environment} tool takes one or more
4528 packages, builds all of their inputs, and creates a shell
4529 environment to use them.
4531 The general syntax is:
4534 guix environment @var{options} @var{package}@dots{}
4537 The following example spawns a new shell set up for the development of
4541 guix environment guile
4544 If the needed dependencies are not built yet, @command{guix environment}
4545 automatically builds them. The environment of the new shell is an augmented
4546 version of the environment that @command{guix environment} was run in.
4547 It contains the necessary search paths for building the given package
4548 added to the existing environment variables. To create a ``pure''
4549 environment, in which the original environment variables have been unset,
4550 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4551 environment variables such as @code{PATH} in their @file{~/.bashrc}
4552 file. As a consequence, when @code{guix environment} launches it, Bash
4553 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4554 environment variables. It is an error to define such environment
4555 variables in @file{.bashrc}; instead, they should be defined in
4556 @file{.bash_profile}, which is sourced only by log-in shells.
4557 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4558 details on Bash start-up files.}.
4560 @vindex GUIX_ENVIRONMENT
4561 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4562 variable in the shell it spawns; its value is the file name of the
4563 profile of this environment. This allows users to, say, define a
4564 specific prompt for development environments in their @file{.bashrc}
4565 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4568 if [ -n "$GUIX_ENVIRONMENT" ]
4570 export PS1="\u@@\h \w [dev]\$ "
4575 ...@: or to browse the profile:
4578 $ ls "$GUIX_ENVIRONMENT/bin"
4581 Additionally, more than one package may be specified, in which case the
4582 union of the inputs for the given packages are used. For example, the
4583 command below spawns a shell where all of the dependencies of both Guile
4584 and Emacs are available:
4587 guix environment guile emacs
4590 Sometimes an interactive shell session is not desired. An arbitrary
4591 command may be invoked by placing the @code{--} token to separate the
4592 command from the rest of the arguments:
4595 guix environment guile -- make -j4
4598 In other situations, it is more convenient to specify the list of
4599 packages needed in the environment. For example, the following command
4600 runs @command{python} from an environment containing Python@tie{}2.7 and
4604 guix environment --ad-hoc python2-numpy python-2.7 -- python
4607 Furthermore, one might want the dependencies of a package and also some
4608 additional packages that are not build-time or runtime dependencies, but
4609 are useful when developing nonetheless. Because of this, the
4610 @code{--ad-hoc} flag is positional. Packages appearing before
4611 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4612 added to the environment. Packages appearing after are interpreted as
4613 packages that will be added to the environment directly. For example,
4614 the following command creates a Guix development environment that
4615 additionally includes Git and strace:
4618 guix environment guix --ad-hoc git strace
4621 Sometimes it is desirable to isolate the environment as much as
4622 possible, for maximal purity and reproducibility. In particular, when
4623 using Guix on a host distro that is not Guix System, it is desirable to
4624 prevent access to @file{/usr/bin} and other system-wide resources from
4625 the development environment. For example, the following command spawns
4626 a Guile REPL in a ``container'' where only the store and the current
4627 working directory are mounted:
4630 guix environment --ad-hoc --container guile -- guile
4634 The @code{--container} option requires Linux-libre 3.19 or newer.
4637 The available options are summarized below.
4640 @item --root=@var{file}
4641 @itemx -r @var{file}
4642 @cindex persistent environment
4643 @cindex garbage collector root, for environments
4644 Make @var{file} a symlink to the profile for this environment, and
4645 register it as a garbage collector root.
4647 This is useful if you want to protect your environment from garbage
4648 collection, to make it ``persistent''.
4650 When this option is omitted, the environment is protected from garbage
4651 collection only for the duration of the @command{guix environment}
4652 session. This means that next time you recreate the same environment,
4653 you could have to rebuild or re-download packages. @xref{Invoking guix
4654 gc}, for more on GC roots.
4656 @item --expression=@var{expr}
4657 @itemx -e @var{expr}
4658 Create an environment for the package or list of packages that
4659 @var{expr} evaluates to.
4661 For example, running:
4664 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4667 starts a shell with the environment for this specific variant of the
4673 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4676 starts a shell with all the base system packages available.
4678 The above commands only use the default output of the given packages.
4679 To select other outputs, two element tuples can be specified:
4682 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4685 @item --load=@var{file}
4686 @itemx -l @var{file}
4687 Create an environment for the package or list of packages that the code
4688 within @var{file} evaluates to.
4690 As an example, @var{file} might contain a definition like this
4691 (@pxref{Defining Packages}):
4694 @verbatiminclude environment-gdb.scm
4697 @item --manifest=@var{file}
4698 @itemx -m @var{file}
4699 Create an environment for the packages contained in the manifest object
4700 returned by the Scheme code in @var{file}.
4702 This is similar to the same-named option in @command{guix package}
4703 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4707 Include all specified packages in the resulting environment, as if an
4708 @i{ad hoc} package were defined with them as inputs. This option is
4709 useful for quickly creating an environment without having to write a
4710 package expression to contain the desired inputs.
4712 For instance, the command:
4715 guix environment --ad-hoc guile guile-sdl -- guile
4718 runs @command{guile} in an environment where Guile and Guile-SDL are
4721 Note that this example implicitly asks for the default output of
4722 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4723 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4724 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4726 This option may be composed with the default behavior of @command{guix
4727 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4728 as packages whose dependencies will be added to the environment, the
4729 default behavior. Packages appearing after are interpreted as packages
4730 that will be added to the environment directly.
4733 Unset existing environment variables when building the new environment, except
4734 those specified with @option{--preserve} (see below.) This has the effect of
4735 creating an environment in which search paths only contain package inputs.
4737 @item --preserve=@var{regexp}
4738 @itemx -E @var{regexp}
4739 When used alongside @option{--pure}, preserve the environment variables
4740 matching @var{regexp}---in other words, put them on a ``white list'' of
4741 environment variables that must be preserved. This option can be repeated
4745 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4749 This example runs @command{mpirun} in a context where the only environment
4750 variables defined are @code{PATH}, environment variables whose name starts
4751 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4754 @item --search-paths
4755 Display the environment variable definitions that make up the
4758 @item --system=@var{system}
4759 @itemx -s @var{system}
4760 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4765 Run @var{command} within an isolated container. The current working
4766 directory outside the container is mapped inside the container.
4767 Additionally, unless overridden with @code{--user}, a dummy home
4768 directory is created that matches the current user's home directory, and
4769 @file{/etc/passwd} is configured accordingly.
4771 The spawned process runs as the current user outside the container. Inside
4772 the container, it has the same UID and GID as the current user, unless
4773 @option{--user} is passed (see below.)
4777 For containers, share the network namespace with the host system.
4778 Containers created without this flag only have access to the loopback
4781 @item --link-profile
4783 For containers, link the environment profile to
4784 @file{~/.guix-profile} within the container. This is equivalent to
4785 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4786 within the container. Linking will fail and abort the environment if
4787 the directory already exists, which will certainly be the case if
4788 @command{guix environment} was invoked in the user's home directory.
4790 Certain packages are configured to look in
4791 @code{~/.guix-profile} for configuration files and data;@footnote{For
4792 example, the @code{fontconfig} package inspects
4793 @file{~/.guix-profile/share/fonts} for additional fonts.}
4794 @code{--link-profile} allows these programs to behave as expected within
4797 @item --user=@var{user}
4798 @itemx -u @var{user}
4799 For containers, use the username @var{user} in place of the current
4800 user. The generated @file{/etc/passwd} entry within the container will
4801 contain the name @var{user}, the home directory will be
4802 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4803 the UID and GID inside the container are 1000. @var{user}
4804 need not exist on the system.
4806 Additionally, any shared or exposed path (see @code{--share} and
4807 @code{--expose} respectively) whose target is within the current user's
4808 home directory will be remapped relative to @file{/home/USER}; this
4809 includes the automatic mapping of the current working directory.
4812 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4814 guix environment --container --user=foo \
4815 --expose=$HOME/test \
4816 --expose=/tmp/target=$HOME/target
4819 While this will limit the leaking of user identity through home paths
4820 and each of the user fields, this is only one useful component of a
4821 broader privacy/anonymity solution---not one in and of itself.
4824 For containers, the default behavior is to share the current working
4825 directory with the isolated container and immediately change to that
4826 directory within the container. If this is undesirable, @code{--no-cwd}
4827 will cause the current working directory to @emph{not} be automatically
4828 shared and will change to the user's home directory within the container
4829 instead. See also @code{--user}.
4831 @item --expose=@var{source}[=@var{target}]
4832 For containers, expose the file system @var{source} from the host system
4833 as the read-only file system @var{target} within the container. If
4834 @var{target} is not specified, @var{source} is used as the target mount
4835 point in the container.
4837 The example below spawns a Guile REPL in a container in which the user's
4838 home directory is accessible read-only via the @file{/exchange}
4842 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
4845 @item --share=@var{source}[=@var{target}]
4846 For containers, share the file system @var{source} from the host system
4847 as the writable file system @var{target} within the container. If
4848 @var{target} is not specified, @var{source} is used as the target mount
4849 point in the container.
4851 The example below spawns a Guile REPL in a container in which the user's
4852 home directory is accessible for both reading and writing via the
4853 @file{/exchange} directory:
4856 guix environment --container --share=$HOME=/exchange --ad-hoc guile -- guile
4860 @command{guix environment}
4861 also supports all of the common build options that @command{guix
4862 build} supports (@pxref{Common Build Options}) as well as package
4863 transformation options (@pxref{Package Transformation Options}).
4865 @node Invoking guix pack
4866 @section Invoking @command{guix pack}
4868 Occasionally you want to pass software to people who are not (yet!)
4869 lucky enough to be using Guix. You'd tell them to run @command{guix
4870 package -i @var{something}}, but that's not possible in this case. This
4871 is where @command{guix pack} comes in.
4874 If you are looking for ways to exchange binaries among machines that
4875 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
4876 publish}, and @ref{Invoking guix archive}.
4881 @cindex application bundle
4882 @cindex software bundle
4883 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
4884 @dfn{software bundle}: it creates a tarball or some other archive
4885 containing the binaries of the software you're interested in, and all
4886 its dependencies. The resulting archive can be used on any machine that
4887 does not have Guix, and people can run the exact same binaries as those
4888 you have with Guix. The pack itself is created in a bit-reproducible
4889 fashion, so anyone can verify that it really contains the build results
4890 that you pretend to be shipping.
4892 For example, to create a bundle containing Guile, Emacs, Geiser, and all
4893 their dependencies, you can run:
4896 $ guix pack guile emacs geiser
4898 /gnu/store/@dots{}-pack.tar.gz
4901 The result here is a tarball containing a @file{/gnu/store} directory
4902 with all the relevant packages. The resulting tarball contains a
4903 @dfn{profile} with the three packages of interest; the profile is the
4904 same as would be created by @command{guix package -i}. It is this
4905 mechanism that is used to create Guix's own standalone binary tarball
4906 (@pxref{Binary Installation}).
4908 Users of this pack would have to run
4909 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
4910 find inconvenient. To work around it, you can create, say, a
4911 @file{/opt/gnu/bin} symlink to the profile:
4914 guix pack -S /opt/gnu/bin=bin guile emacs geiser
4918 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
4920 @cindex relocatable binaries, with @command{guix pack}
4921 What if the recipient of your pack does not have root privileges on
4922 their machine, and thus cannot unpack it in the root file system? In
4923 that case, you will want to use the @code{--relocatable} option (see
4924 below). This option produces @dfn{relocatable binaries}, meaning they
4925 they can be placed anywhere in the file system hierarchy: in the example
4926 above, users can unpack your tarball in their home directory and
4927 directly run @file{./opt/gnu/bin/guile}.
4929 @cindex Docker, build an image with guix pack
4930 Alternatively, you can produce a pack in the Docker image format using
4931 the following command:
4934 guix pack -f docker guile emacs geiser
4938 The result is a tarball that can be passed to the @command{docker load}
4940 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
4941 documentation} for more information.
4943 @cindex Singularity, build an image with guix pack
4944 @cindex SquashFS, build an image with guix pack
4945 Yet another option is to produce a SquashFS image with the following
4949 guix pack -f squashfs guile emacs geiser
4953 The result is a SquashFS file system image that can either be mounted or
4954 directly be used as a file system container image with the
4955 @uref{https://singularity.lbl.gov, Singularity container execution
4956 environment}, using commands like @command{singularity shell} or
4957 @command{singularity exec}.
4959 Several command-line options allow you to customize your pack:
4962 @item --format=@var{format}
4963 @itemx -f @var{format}
4964 Produce a pack in the given @var{format}.
4966 The available formats are:
4970 This is the default format. It produces a tarball containing all the
4971 specified binaries and symlinks.
4974 This produces a tarball that follows the
4975 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
4976 Docker Image Specification}. The ``repository name'' as it appears in
4977 the output of the @command{docker images} command is computed from
4978 package names passed on the command line or in the manifest file.
4981 This produces a SquashFS image containing all the specified binaries and
4982 symlinks, as well as empty mount points for virtual file systems like
4986 @cindex relocatable binaries
4989 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
4990 anywhere in the file system hierarchy and run from there.
4992 When this option is passed once, the resulting binaries require support for
4993 @dfn{user namespaces} in the kernel Linux; when passed
4994 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
4995 PRoot support, can be thought of as the abbreviation of ``Really
4996 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
4997 if user namespaces are unavailable, and essentially work anywhere---see below
4998 for the implications.
5000 For example, if you create a pack containing Bash with:
5003 guix pack -RR -S /mybin=bin bash
5007 ...@: you can copy that pack to a machine that lacks Guix, and from your
5008 home directory as a normal user, run:
5016 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5017 @file{/gnu/store} shows up and contains all the dependencies of
5018 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5019 altogether! That is probably the simplest way to deploy Guix-built
5020 software on a non-Guix machine.
5023 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5024 the kernel Linux, which allows unprivileged users to mount or change root.
5025 Old versions of Linux did not support it, and some GNU/Linux distributions
5028 To produce relocatable binaries that work even in the absence of user
5029 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5030 case, binaries will try user namespace support and fall back to PRoot if user
5031 namespaces are not supported.
5033 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
5034 support for file system virtualization. It achieves that by using the
5035 @code{ptrace} system call on the running program. This approach has the
5036 advantage to work without requiring special kernel support, but it incurs
5037 run-time overhead every time a system call is made.
5040 @cindex entry point, for Docker images
5041 @item --entry-point=@var{command}
5042 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5043 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5044 support it. @var{command} must be relative to the profile contained in the
5047 The entry point specifies the command that tools like @code{docker run} or
5048 @code{singularity run} automatically start by default. For example, you can
5052 guix pack -f docker --entry-point=bin/guile guile
5055 The resulting pack can easily be loaded and @code{docker run} with no extra
5056 arguments will spawn @code{bin/guile}:
5059 docker load -i pack.tar.gz
5060 docker run @var{image-id}
5063 @item --expression=@var{expr}
5064 @itemx -e @var{expr}
5065 Consider the package @var{expr} evaluates to.
5067 This has the same purpose as the same-named option in @command{guix
5068 build} (@pxref{Additional Build Options, @code{--expression} in
5069 @command{guix build}}).
5071 @item --manifest=@var{file}
5072 @itemx -m @var{file}
5073 Use the packages contained in the manifest object returned by the Scheme
5076 This has a similar purpose as the same-named option in @command{guix
5077 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5078 same manifest files. It allows you to define a collection of packages
5079 once and use it both for creating profiles and for creating archives
5080 for use on machines that do not have Guix installed. Note that you can
5081 specify @emph{either} a manifest file @emph{or} a list of packages,
5084 @item --system=@var{system}
5085 @itemx -s @var{system}
5086 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5087 the system type of the build host.
5089 @item --target=@var{triplet}
5090 @cindex cross-compilation
5091 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5092 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
5093 configuration triplets,, autoconf, Autoconf}).
5095 @item --compression=@var{tool}
5096 @itemx -C @var{tool}
5097 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5098 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
5100 @item --symlink=@var{spec}
5101 @itemx -S @var{spec}
5102 Add the symlinks specified by @var{spec} to the pack. This option can
5103 appear several times.
5105 @var{spec} has the form @code{@var{source}=@var{target}}, where
5106 @var{source} is the symlink that will be created and @var{target} is the
5109 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5110 symlink pointing to the @file{bin} sub-directory of the profile.
5112 @item --save-provenance
5113 Save provenance information for the packages passed on the command line.
5114 Provenance information includes the URL and commit of the channels in use
5117 Provenance information is saved in the
5118 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5119 usual package metadata---the name and version of each package, their
5120 propagated inputs, and so on. It is useful information to the recipient of
5121 the pack, who then knows how the pack was (supposedly) obtained.
5123 This option is not enabled by default because, like timestamps, provenance
5124 information contributes nothing to the build process. In other words, there
5125 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5126 Recording such ``silent'' metadata in the output thus potentially breaks the
5127 source-to-binary bitwise reproducibility property.
5129 @item --root=@var{file}
5130 @itemx -r @var{file}
5131 @cindex garbage collector root, for packs
5132 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5135 @item --localstatedir
5136 @itemx --profile-name=@var{name}
5137 Include the ``local state directory'', @file{/var/guix}, in the resulting
5138 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5139 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5140 @file{~root/.guix-profile}.
5142 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5143 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5144 the pack means that the store is ``complete'' and manageable by Guix;
5145 not providing it pack means that the store is ``dead'': items cannot be
5146 added to it or removed from it after extraction of the pack.
5148 One use case for this is the Guix self-contained binary tarball
5149 (@pxref{Binary Installation}).
5152 Use the bootstrap binaries to build the pack. This option is only
5153 useful to Guix developers.
5156 In addition, @command{guix pack} supports all the common build options
5157 (@pxref{Common Build Options}) and all the package transformation
5158 options (@pxref{Package Transformation Options}).
5161 @c *********************************************************************
5162 @node Programming Interface
5163 @chapter Programming Interface
5165 GNU Guix provides several Scheme programming interfaces (APIs) to
5166 define, build, and query packages. The first interface allows users to
5167 write high-level package definitions. These definitions refer to
5168 familiar packaging concepts, such as the name and version of a package,
5169 its build system, and its dependencies. These definitions can then be
5170 turned into concrete build actions.
5172 Build actions are performed by the Guix daemon, on behalf of users. In a
5173 standard setup, the daemon has write access to the store---the
5174 @file{/gnu/store} directory---whereas users do not. The recommended
5175 setup also has the daemon perform builds in chroots, under a specific
5176 build users, to minimize interference with the rest of the system.
5179 Lower-level APIs are available to interact with the daemon and the
5180 store. To instruct the daemon to perform a build action, users actually
5181 provide it with a @dfn{derivation}. A derivation is a low-level
5182 representation of the build actions to be taken, and the environment in
5183 which they should occur---derivations are to package definitions what
5184 assembly is to C programs. The term ``derivation'' comes from the fact
5185 that build results @emph{derive} from them.
5187 This chapter describes all these APIs in turn, starting from high-level
5188 package definitions.
5191 * Package Modules:: Packages from the programmer's viewpoint.
5192 * Defining Packages:: Defining new packages.
5193 * Build Systems:: Specifying how packages are built.
5194 * The Store:: Manipulating the package store.
5195 * Derivations:: Low-level interface to package derivations.
5196 * The Store Monad:: Purely functional interface to the store.
5197 * G-Expressions:: Manipulating build expressions.
5198 * Invoking guix repl:: Fiddling with Guix interactively.
5201 @node Package Modules
5202 @section Package Modules
5204 From a programming viewpoint, the package definitions of the
5205 GNU distribution are provided by Guile modules in the @code{(gnu packages
5206 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5207 packages @dots{})} module name space are not necessarily ``GNU
5208 packages''. This module naming scheme follows the usual Guile module
5209 naming convention: @code{gnu} means that these modules are distributed
5210 as part of the GNU system, and @code{packages} identifies modules that
5211 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5212 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5213 module exports a variable named @code{emacs}, which is bound to a
5214 @code{<package>} object (@pxref{Defining Packages}).
5216 The @code{(gnu packages @dots{})} module name space is
5217 automatically scanned for packages by the command-line tools. For
5218 instance, when running @code{guix install emacs}, all the @code{(gnu
5219 packages @dots{})} modules are scanned until one that exports a package
5220 object whose name is @code{emacs} is found. This package search
5221 facility is implemented in the @code{(gnu packages)} module.
5223 @cindex customization, of packages
5224 @cindex package module search path
5225 Users can store package definitions in modules with different
5226 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5227 name and module name must match. For instance, the @code{(my-packages
5228 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5229 relative to the load path specified with @option{--load-path} or
5230 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5231 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5232 these package definitions visible to the user interfaces:
5236 By adding the directory containing your package modules to the search path
5237 with the @code{-L} flag of @command{guix package} and other commands
5238 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5239 environment variable described below.
5242 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5243 pulls from it. A channel is essentially a Git repository containing package
5244 modules. @xref{Channels}, for more information on how to define and use
5248 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5250 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5251 This is a colon-separated list of directories to search for additional
5252 package modules. Directories listed in this variable take precedence
5253 over the own modules of the distribution.
5256 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5257 each package is built based solely on other packages in the
5258 distribution. The root of this dependency graph is a small set of
5259 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5260 bootstrap)} module. For more information on bootstrapping,
5261 @pxref{Bootstrapping}.
5263 @node Defining Packages
5264 @section Defining Packages
5266 The high-level interface to package definitions is implemented in the
5267 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5268 example, the package definition, or @dfn{recipe}, for the GNU Hello
5269 package looks like this:
5272 (define-module (gnu packages hello)
5273 #:use-module (guix packages)
5274 #:use-module (guix download)
5275 #:use-module (guix build-system gnu)
5276 #:use-module (guix licenses)
5277 #:use-module (gnu packages gawk))
5279 (define-public hello
5285 (uri (string-append "mirror://gnu/hello/hello-" version
5289 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5290 (build-system gnu-build-system)
5291 (arguments '(#:configure-flags '("--enable-silent-rules")))
5292 (inputs `(("gawk" ,gawk)))
5293 (synopsis "Hello, GNU world: An example GNU package")
5294 (description "Guess what GNU Hello prints!")
5295 (home-page "https://www.gnu.org/software/hello/")
5300 Without being a Scheme expert, the reader may have guessed the meaning
5301 of the various fields here. This expression binds the variable
5302 @code{hello} to a @code{<package>} object, which is essentially a record
5303 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5304 This package object can be inspected using procedures found in the
5305 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5306 returns---surprise!---@code{"hello"}.
5308 With luck, you may be able to import part or all of the definition of
5309 the package you are interested in from another repository, using the
5310 @code{guix import} command (@pxref{Invoking guix import}).
5312 In the example above, @var{hello} is defined in a module of its own,
5313 @code{(gnu packages hello)}. Technically, this is not strictly
5314 necessary, but it is convenient to do so: all the packages defined in
5315 modules under @code{(gnu packages @dots{})} are automatically known to
5316 the command-line tools (@pxref{Package Modules}).
5318 There are a few points worth noting in the above package definition:
5322 The @code{source} field of the package is an @code{<origin>} object
5323 (@pxref{origin Reference}, for the complete reference).
5324 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5325 meaning that the source is a file to be downloaded over FTP or HTTP.
5327 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5328 the GNU mirrors defined in @code{(guix download)}.
5330 The @code{sha256} field specifies the expected SHA256 hash of the file
5331 being downloaded. It is mandatory, and allows Guix to check the
5332 integrity of the file. The @code{(base32 @dots{})} form introduces the
5333 base32 representation of the hash. You can obtain this information with
5334 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5335 hash} (@pxref{Invoking guix hash}).
5338 When needed, the @code{origin} form can also have a @code{patches} field
5339 listing patches to be applied, and a @code{snippet} field giving a
5340 Scheme expression to modify the source code.
5343 @cindex GNU Build System
5344 The @code{build-system} field specifies the procedure to build the
5345 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5346 represents the familiar GNU Build System, where packages may be
5347 configured, built, and installed with the usual @code{./configure &&
5348 make && make check && make install} command sequence.
5351 The @code{arguments} field specifies options for the build system
5352 (@pxref{Build Systems}). Here it is interpreted by
5353 @var{gnu-build-system} as a request run @file{configure} with the
5354 @code{--enable-silent-rules} flag.
5360 What about these quote (@code{'}) characters? They are Scheme syntax to
5361 introduce a literal list; @code{'} is synonymous with @code{quote}.
5362 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5363 for details. Here the value of the @code{arguments} field is a list of
5364 arguments passed to the build system down the road, as with @code{apply}
5365 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5368 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5369 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5370 @code{#:configure-flags} is a keyword used to pass a keyword argument
5371 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5375 The @code{inputs} field specifies inputs to the build process---i.e.,
5376 build-time or run-time dependencies of the package. Here, we define an
5377 input called @code{"gawk"} whose value is that of the @var{gawk}
5378 variable; @var{gawk} is itself bound to a @code{<package>} object.
5380 @cindex backquote (quasiquote)
5383 @cindex comma (unquote)
5387 @findex unquote-splicing
5388 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5389 us to introduce a literal list in the @code{inputs} field, while
5390 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5391 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5394 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5395 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5396 of ensuring that they are present (@pxref{Build Systems}).
5398 However, any other dependencies need to be specified in the
5399 @code{inputs} field. Any dependency not specified here will simply be
5400 unavailable to the build process, possibly leading to a build failure.
5403 @xref{package Reference}, for a full description of possible fields.
5405 Once a package definition is in place, the
5406 package may actually be built using the @code{guix build} command-line
5407 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5408 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5409 package definition using the @command{guix edit} command
5410 (@pxref{Invoking guix edit}).
5411 @xref{Packaging Guidelines}, for
5412 more information on how to test package definitions, and
5413 @ref{Invoking guix lint}, for information on how to check a definition
5414 for style conformance.
5415 @vindex GUIX_PACKAGE_PATH
5416 Lastly, @pxref{Channels}, for information
5417 on how to extend the distribution by adding your own package definitions
5420 Finally, updating the package definition to a new upstream version
5421 can be partly automated by the @command{guix refresh} command
5422 (@pxref{Invoking guix refresh}).
5424 Behind the scenes, a derivation corresponding to the @code{<package>}
5425 object is first computed by the @code{package-derivation} procedure.
5426 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5427 The build actions it prescribes may then be realized by using the
5428 @code{build-derivations} procedure (@pxref{The Store}).
5430 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5431 Return the @code{<derivation>} object of @var{package} for @var{system}
5432 (@pxref{Derivations}).
5434 @var{package} must be a valid @code{<package>} object, and @var{system}
5435 must be a string denoting the target system type---e.g.,
5436 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5437 must be a connection to the daemon, which operates on the store
5438 (@pxref{The Store}).
5442 @cindex cross-compilation
5443 Similarly, it is possible to compute a derivation that cross-builds a
5444 package for some other system:
5446 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5447 @var{package} @var{target} [@var{system}]
5448 Return the @code{<derivation>} object of @var{package} cross-built from
5449 @var{system} to @var{target}.
5451 @var{target} must be a valid GNU triplet denoting the target hardware
5452 and operating system, such as @code{"mips64el-linux-gnu"}
5453 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5456 @cindex package transformations
5457 @cindex input rewriting
5458 @cindex dependency tree rewriting
5459 Packages can be manipulated in arbitrary ways. An example of a useful
5460 transformation is @dfn{input rewriting}, whereby the dependency tree of
5461 a package is rewritten by replacing specific inputs by others:
5463 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5464 [@var{rewrite-name}]
5465 Return a procedure that, when passed a package, replaces its direct and
5466 indirect dependencies (but not its implicit inputs) according to
5467 @var{replacements}. @var{replacements} is a list of package pairs; the
5468 first element of each pair is the package to replace, and the second one
5471 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5472 the name of a package and returns its new name after rewrite.
5476 Consider this example:
5479 (define libressl-instead-of-openssl
5480 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5482 (package-input-rewriting `((,openssl . ,libressl))))
5484 (define git-with-libressl
5485 (libressl-instead-of-openssl git))
5489 Here we first define a rewriting procedure that replaces @var{openssl}
5490 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5491 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5492 This is exactly what the @option{--with-input} command-line option does
5493 (@pxref{Package Transformation Options, @option{--with-input}}).
5495 The following variant of @code{package-input-rewriting} can match packages to
5496 be replaced by name rather than by identity.
5498 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5499 Return a procedure that, given a package, applies the given @var{replacements} to
5500 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5501 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5502 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5503 replacement for that package.
5506 The example above could be rewritten this way:
5509 (define libressl-instead-of-openssl
5510 ;; Replace all the packages called "openssl" with LibreSSL.
5511 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5514 The key difference here is that, this time, packages are matched by spec and
5515 not by identity. In other words, any package in the graph that is called
5516 @code{openssl} will be replaced.
5518 A more generic procedure to rewrite a package dependency graph is
5519 @code{package-mapping}: it supports arbitrary changes to nodes in the
5522 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5523 Return a procedure that, given a package, applies @var{proc} to all the packages
5524 depended on and returns the resulting package. The procedure stops recursion
5525 when @var{cut?} returns true for a given package.
5529 * package Reference:: The package data type.
5530 * origin Reference:: The origin data type.
5534 @node package Reference
5535 @subsection @code{package} Reference
5537 This section summarizes all the options available in @code{package}
5538 declarations (@pxref{Defining Packages}).
5540 @deftp {Data Type} package
5541 This is the data type representing a package recipe.
5545 The name of the package, as a string.
5547 @item @code{version}
5548 The version of the package, as a string.
5551 An object telling how the source code for the package should be
5552 acquired. Most of the time, this is an @code{origin} object, which
5553 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5554 can also be any other ``file-like'' object such as a @code{local-file},
5555 which denotes a file from the local file system (@pxref{G-Expressions,
5556 @code{local-file}}).
5558 @item @code{build-system}
5559 The build system that should be used to build the package (@pxref{Build
5562 @item @code{arguments} (default: @code{'()})
5563 The arguments that should be passed to the build system. This is a
5564 list, typically containing sequential keyword-value pairs.
5566 @item @code{inputs} (default: @code{'()})
5567 @itemx @code{native-inputs} (default: @code{'()})
5568 @itemx @code{propagated-inputs} (default: @code{'()})
5569 @cindex inputs, of packages
5570 These fields list dependencies of the package. Each one is a list of
5571 tuples, where each tuple has a label for the input (a string) as its
5572 first element, a package, origin, or derivation as its second element,
5573 and optionally the name of the output thereof that should be used, which
5574 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5575 more on package outputs). For example, the list below specifies three
5579 `(("libffi" ,libffi)
5580 ("libunistring" ,libunistring)
5581 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5584 @cindex cross compilation, package dependencies
5585 The distinction between @code{native-inputs} and @code{inputs} is
5586 necessary when considering cross-compilation. When cross-compiling,
5587 dependencies listed in @code{inputs} are built for the @emph{target}
5588 architecture; conversely, dependencies listed in @code{native-inputs}
5589 are built for the architecture of the @emph{build} machine.
5591 @code{native-inputs} is typically used to list tools needed at
5592 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5593 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5594 this area (@pxref{Invoking guix lint}).
5596 @anchor{package-propagated-inputs}
5597 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5598 specified packages will be automatically installed alongside the package
5599 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5600 package}}, for information on how @command{guix package} deals with
5603 For example this is necessary when a C/C++ library needs headers of
5604 another library to compile, or when a pkg-config file refers to another
5605 one @i{via} its @code{Requires} field.
5607 Another example where @code{propagated-inputs} is useful is for languages
5608 that lack a facility to record the run-time search path akin to the
5609 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5610 more. To ensure that libraries written in those languages can find
5611 library code they depend on at run time, run-time dependencies must be
5612 listed in @code{propagated-inputs} rather than @code{inputs}.
5614 @item @code{outputs} (default: @code{'("out")})
5615 The list of output names of the package. @xref{Packages with Multiple
5616 Outputs}, for typical uses of additional outputs.
5618 @item @code{native-search-paths} (default: @code{'()})
5619 @itemx @code{search-paths} (default: @code{'()})
5620 A list of @code{search-path-specification} objects describing
5621 search-path environment variables honored by the package.
5623 @item @code{replacement} (default: @code{#f})
5624 This must be either @code{#f} or a package object that will be used as a
5625 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5628 @item @code{synopsis}
5629 A one-line description of the package.
5631 @item @code{description}
5632 A more elaborate description of the package.
5634 @item @code{license}
5635 @cindex license, of packages
5636 The license of the package; a value from @code{(guix licenses)},
5637 or a list of such values.
5639 @item @code{home-page}
5640 The URL to the home-page of the package, as a string.
5642 @item @code{supported-systems} (default: @var{%supported-systems})
5643 The list of systems supported by the package, as strings of the form
5644 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5646 @item @code{maintainers} (default: @code{'()})
5647 The list of maintainers of the package, as @code{maintainer} objects.
5649 @item @code{location} (default: source location of the @code{package} form)
5650 The source location of the package. It is useful to override this when
5651 inheriting from another package, in which case this field is not
5652 automatically corrected.
5656 @deffn {Scheme Syntax} this-package
5657 When used in the @emph{lexical scope} of a package field definition, this
5658 identifier resolves to the package being defined.
5660 The example below shows how to add a package as a native input of itself when
5668 ;; When cross-compiled, Guile, for example, depends on
5669 ;; a native version of itself. Add it here.
5670 (native-inputs (if (%current-target-system)
5671 `(("self" ,this-package))
5675 It is an error to refer to @code{this-package} outside a package definition.
5678 @node origin Reference
5679 @subsection @code{origin} Reference
5681 This section summarizes all the options available in @code{origin}
5682 declarations (@pxref{Defining Packages}).
5684 @deftp {Data Type} origin
5685 This is the data type representing a source code origin.
5689 An object containing the URI of the source. The object type depends on
5690 the @code{method} (see below). For example, when using the
5691 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5692 values are: a URL represented as a string, or a list thereof.
5695 A procedure that handles the URI.
5700 @item @var{url-fetch} from @code{(guix download)}
5701 download a file from the HTTP, HTTPS, or FTP URL specified in the
5705 @item @var{git-fetch} from @code{(guix git-download)}
5706 clone the Git version control repository, and check out the revision
5707 specified in the @code{uri} field as a @code{git-reference} object; a
5708 @code{git-reference} looks like this:
5712 (url "https://git.savannah.gnu.org/git/hello.git")
5718 A bytevector containing the SHA-256 hash of the source. Typically the
5719 @code{base32} form is used here to generate the bytevector from a
5722 You can obtain this information using @code{guix download}
5723 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5726 @item @code{file-name} (default: @code{#f})
5727 The file name under which the source code should be saved. When this is
5728 @code{#f}, a sensible default value will be used in most cases. In case
5729 the source is fetched from a URL, the file name from the URL will be
5730 used. For version control checkouts, it is recommended to provide the
5731 file name explicitly because the default is not very descriptive.
5733 @item @code{patches} (default: @code{'()})
5734 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5735 file-like objects}) pointing to patches to be applied to the source.
5737 This list of patches must be unconditional. In particular, it cannot
5738 depend on the value of @code{%current-system} or
5739 @code{%current-target-system}.
5741 @item @code{snippet} (default: @code{#f})
5742 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5743 in the source directory. This is a convenient way to modify the source,
5744 sometimes more convenient than a patch.
5746 @item @code{patch-flags} (default: @code{'("-p1")})
5747 A list of command-line flags that should be passed to the @code{patch}
5750 @item @code{patch-inputs} (default: @code{#f})
5751 Input packages or derivations to the patching process. When this is
5752 @code{#f}, the usual set of inputs necessary for patching are provided,
5753 such as GNU@tie{}Patch.
5755 @item @code{modules} (default: @code{'()})
5756 A list of Guile modules that should be loaded during the patching
5757 process and while running the code in the @code{snippet} field.
5759 @item @code{patch-guile} (default: @code{#f})
5760 The Guile package that should be used in the patching process. When
5761 this is @code{#f}, a sensible default is used.
5767 @section Build Systems
5769 @cindex build system
5770 Each package definition specifies a @dfn{build system} and arguments for
5771 that build system (@pxref{Defining Packages}). This @code{build-system}
5772 field represents the build procedure of the package, as well as implicit
5773 dependencies of that build procedure.
5775 Build systems are @code{<build-system>} objects. The interface to
5776 create and manipulate them is provided by the @code{(guix build-system)}
5777 module, and actual build systems are exported by specific modules.
5779 @cindex bag (low-level package representation)
5780 Under the hood, build systems first compile package objects to
5781 @dfn{bags}. A @dfn{bag} is like a package, but with less
5782 ornamentation---in other words, a bag is a lower-level representation of
5783 a package, which includes all the inputs of that package, including some
5784 that were implicitly added by the build system. This intermediate
5785 representation is then compiled to a derivation (@pxref{Derivations}).
5787 Build systems accept an optional list of @dfn{arguments}. In package
5788 definitions, these are passed @i{via} the @code{arguments} field
5789 (@pxref{Defining Packages}). They are typically keyword arguments
5790 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5791 Guile Reference Manual}). The value of these arguments is usually
5792 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5793 by the daemon (@pxref{Derivations}).
5795 The main build system is @var{gnu-build-system}, which implements the
5796 standard build procedure for GNU and many other packages. It
5797 is provided by the @code{(guix build-system gnu)} module.
5799 @defvr {Scheme Variable} gnu-build-system
5800 @var{gnu-build-system} represents the GNU Build System, and variants
5801 thereof (@pxref{Configuration, configuration and makefile conventions,,
5802 standards, GNU Coding Standards}).
5804 @cindex build phases
5805 In a nutshell, packages using it are configured, built, and installed with
5806 the usual @code{./configure && make && make check && make install}
5807 command sequence. In practice, a few additional steps are often needed.
5808 All these steps are split up in separate @dfn{phases},
5809 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5810 modules for more details about the build phases.}:
5814 Unpack the source tarball, and change the current directory to the
5815 extracted source tree. If the source is actually a directory, copy it
5816 to the build tree, and enter that directory.
5818 @item patch-source-shebangs
5819 Patch shebangs encountered in source files so they refer to the right
5820 store file names. For instance, this changes @code{#!/bin/sh} to
5821 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
5824 Run the @file{configure} script with a number of default options, such
5825 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
5826 by the @code{#:configure-flags} argument.
5829 Run @code{make} with the list of flags specified with
5830 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
5831 (the default), build with @code{make -j}.
5834 Run @code{make check}, or some other target specified with
5835 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
5836 @code{#:parallel-tests?} argument is true (the default), run @code{make
5840 Run @code{make install} with the flags listed in @code{#:make-flags}.
5842 @item patch-shebangs
5843 Patch shebangs on the installed executable files.
5846 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
5847 is false), copying them to the @code{debug} output when available
5848 (@pxref{Installing Debugging Files}).
5851 @vindex %standard-phases
5852 The build-side module @code{(guix build gnu-build-system)} defines
5853 @var{%standard-phases} as the default list of build phases.
5854 @var{%standard-phases} is a list of symbol/procedure pairs, where the
5855 procedure implements the actual phase.
5857 The list of phases used for a particular package can be changed with the
5858 @code{#:phases} parameter. For instance, passing:
5861 #:phases (modify-phases %standard-phases (delete 'configure))
5864 means that all the phases described above will be used, except the
5865 @code{configure} phase.
5867 In addition, this build system ensures that the ``standard'' environment
5868 for GNU packages is available. This includes tools such as GCC, libc,
5869 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
5870 build-system gnu)} module for a complete list). We call these the
5871 @dfn{implicit inputs} of a package, because package definitions do not
5872 have to mention them.
5875 Other @code{<build-system>} objects are defined to support other
5876 conventions and tools used by free software packages. They inherit most
5877 of @var{gnu-build-system}, and differ mainly in the set of inputs
5878 implicitly added to the build process, and in the list of phases
5879 executed. Some of these build systems are listed below.
5881 @defvr {Scheme Variable} ant-build-system
5882 This variable is exported by @code{(guix build-system ant)}. It
5883 implements the build procedure for Java packages that can be built with
5884 @url{https://ant.apache.org/, Ant build tool}.
5886 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
5887 provided by the @code{icedtea} package to the set of inputs. Different
5888 packages can be specified with the @code{#:ant} and @code{#:jdk}
5889 parameters, respectively.
5891 When the original package does not provide a suitable Ant build file,
5892 the parameter @code{#:jar-name} can be used to generate a minimal Ant
5893 build file @file{build.xml} with tasks to build the specified jar
5894 archive. In this case the parameter @code{#:source-dir} can be used to
5895 specify the source sub-directory, defaulting to ``src''.
5897 The @code{#:main-class} parameter can be used with the minimal ant
5898 buildfile to specify the main class of the resulting jar. This makes the
5899 jar file executable. The @code{#:test-include} parameter can be used to
5900 specify the list of junit tests to run. It defaults to
5901 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
5902 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
5903 because abstract classes cannot be run as tests.
5905 The parameter @code{#:build-target} can be used to specify the Ant task
5906 that should be run during the @code{build} phase. By default the
5907 ``jar'' task will be run.
5911 @defvr {Scheme Variable} android-ndk-build-system
5912 @cindex Android distribution
5913 @cindex Android NDK build system
5914 This variable is exported by @code{(guix build-system android-ndk)}. It
5915 implements a build procedure for Android NDK (native development kit)
5916 packages using a Guix-specific build process.
5918 The build system assumes that packages install their public interface
5919 (header) files to the subdirectory "include" of the "out" output and
5920 their libraries to the subdirectory "lib" of the "out" output.
5922 It's also assumed that the union of all the dependencies of a package
5923 has no conflicting files.
5925 For the time being, cross-compilation is not supported - so right now
5926 the libraries and header files are assumed to be host tools.
5930 @defvr {Scheme Variable} asdf-build-system/source
5931 @defvrx {Scheme Variable} asdf-build-system/sbcl
5932 @defvrx {Scheme Variable} asdf-build-system/ecl
5934 These variables, exported by @code{(guix build-system asdf)}, implement
5935 build procedures for Common Lisp packages using
5936 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
5937 definition facility for Common Lisp programs and libraries.
5939 The @code{asdf-build-system/source} system installs the packages in
5940 source form, and can be loaded using any common lisp implementation, via
5941 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
5942 systems in the format which a particular implementation understands.
5943 These build systems can also be used to produce executable programs, or
5944 lisp images which contain a set of packages pre-loaded.
5946 The build system uses naming conventions. For binary packages, the
5947 package name should be prefixed with the lisp implementation, such as
5948 @code{sbcl-} for @code{asdf-build-system/sbcl}.
5950 Additionally, the corresponding source package should be labeled using
5951 the same convention as python packages (see @ref{Python Modules}), using
5952 the @code{cl-} prefix.
5954 For binary packages, each system should be defined as a Guix package.
5955 If one package @code{origin} contains several systems, package variants
5956 can be created in order to build all the systems. Source packages,
5957 which use @code{asdf-build-system/source}, may contain several systems.
5959 In order to create executable programs and images, the build-side
5960 procedures @code{build-program} and @code{build-image} can be used.
5961 They should be called in a build phase after the @code{create-symlinks}
5962 phase, so that the system which was just built can be used within the
5963 resulting image. @code{build-program} requires a list of Common Lisp
5964 expressions to be passed as the @code{#:entry-program} argument.
5966 If the system is not defined within its own @code{.asd} file of the same
5967 name, then the @code{#:asd-file} parameter should be used to specify
5968 which file the system is defined in. Furthermore, if the package
5969 defines a system for its tests in a separate file, it will be loaded
5970 before the tests are run if it is specified by the
5971 @code{#:test-asd-file} parameter. If it is not set, the files
5972 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
5973 and @code{test.asd} will be tried if they exist.
5975 If for some reason the package must be named in a different way than the
5976 naming conventions suggest, the @code{#:asd-system-name} parameter can
5977 be used to specify the name of the system.
5981 @defvr {Scheme Variable} cargo-build-system
5982 @cindex Rust programming language
5983 @cindex Cargo (Rust build system)
5984 This variable is exported by @code{(guix build-system cargo)}. It
5985 supports builds of packages using Cargo, the build tool of the
5986 @uref{https://www.rust-lang.org, Rust programming language}.
5988 It adds @code{rustc} and @code{cargo} to the set of inputs.
5989 A different Rust package can be specified with the @code{#:rust} parameter.
5991 Regular cargo dependencies should be added to the package definition via the
5992 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
5993 spec can be a package or a source definition. Note that the spec must
5994 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
5995 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
5996 should be added to the package definition via the
5997 @code{#:cargo-development-inputs} parameter.
5999 In its @code{configure} phase, this build system will make any source inputs
6000 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6001 parameters available to cargo. It will also remove an included
6002 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6003 @code{build} phase. The @code{install} phase installs any crate the binaries
6004 if they are defined by the crate.
6007 @cindex Clojure (programming language)
6008 @cindex simple Clojure build system
6009 @defvr {Scheme Variable} clojure-build-system
6010 This variable is exported by @code{(guix build-system clojure)}. It implements
6011 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6012 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6015 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6016 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6017 @code{#:zip} parameters, respectively.
6019 A list of source directories, test directories and jar names can be specified
6020 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6021 parameters, respectively. Compile directory and main class can be specified
6022 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6023 Other parameters are documented below.
6025 This build system is an extension of @var{ant-build-system}, but with the
6026 following phases changed:
6031 This phase calls @code{compile} in Clojure to compile source files and runs
6032 @command{jar} to create jars from both source files and compiled files
6033 according to the include list and exclude list specified in
6034 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6035 has priority over the include list. These lists consist of symbols
6036 representing Clojure libraries or the special keyword @code{#:all} representing
6037 all Clojure libraries found under the source directories. The parameter
6038 @code{#:omit-source?} decides if source should be included into the jars.
6041 This phase runs tests according to the include list and exclude list specified
6042 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6043 meanings are analogous to that of @code{#:aot-include} and
6044 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6045 stands for all Clojure libraries found under the test directories. The
6046 parameter @code{#:tests?} decides if tests should be run.
6049 This phase installs all jars built previously.
6052 Apart from the above, this build system also contains an additional phase:
6057 This phase installs all top-level files with base name matching
6058 @var{%doc-regex}. A different regex can be specified with the
6059 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6060 directories specified in @code{#:doc-dirs} are installed as well.
6064 @defvr {Scheme Variable} cmake-build-system
6065 This variable is exported by @code{(guix build-system cmake)}. It
6066 implements the build procedure for packages using the
6067 @url{https://www.cmake.org, CMake build tool}.
6069 It automatically adds the @code{cmake} package to the set of inputs.
6070 Which package is used can be specified with the @code{#:cmake}
6073 The @code{#:configure-flags} parameter is taken as a list of flags
6074 passed to the @command{cmake} command. The @code{#:build-type}
6075 parameter specifies in abstract terms the flags passed to the compiler;
6076 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6077 debugging information''), which roughly means that code is compiled with
6078 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6081 @defvr {Scheme Variable} dune-build-system
6082 This variable is exported by @code{(guix build-system dune)}. It
6083 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6084 tool for the OCaml programming language. It is implemented as an extension
6085 of the @code{ocaml-build-system} which is described below. As such, the
6086 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6089 It automatically adds the @code{dune} package to the set of inputs.
6090 Which package is used can be specified with the @code{#:dune}
6093 There is no @code{configure} phase because dune packages typically don't
6094 need to be configured. The @code{#:build-flags} parameter is taken as a
6095 list of flags passed to the @code{dune} command during the build.
6097 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6098 command instead of the more recent @code{dune} command while building
6099 a package. Its default value is @code{#f}.
6101 The @code{#:package} parameter can be passed to specify a package name, which
6102 is useful when a package contains multiple packages and you want to build
6103 only one of them. This is equivalent to passing the @code{-p} argument to
6107 @defvr {Scheme Variable} go-build-system
6108 This variable is exported by @code{(guix build-system go)}. It
6109 implements a build procedure for Go packages using the standard
6110 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6111 Go build mechanisms}.
6113 The user is expected to provide a value for the key @code{#:import-path}
6114 and, in some cases, @code{#:unpack-path}. The
6115 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6116 corresponds to the file system path expected by the package's build
6117 scripts and any referring packages, and provides a unique way to
6118 refer to a Go package. It is typically based on a combination of the
6119 package source code's remote URI and file system hierarchy structure. In
6120 some cases, you will need to unpack the package's source code to a
6121 different directory structure than the one indicated by the import path,
6122 and @code{#:unpack-path} should be used in such cases.
6124 Packages that provide Go libraries should install their source code into
6125 the built output. The key @code{#:install-source?}, which defaults to
6126 @code{#t}, controls whether or not the source code is installed. It can
6127 be set to @code{#f} for packages that only provide executable files.
6130 @defvr {Scheme Variable} glib-or-gtk-build-system
6131 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6132 is intended for use with packages making use of GLib or GTK+.
6134 This build system adds the following two phases to the ones defined by
6135 @var{gnu-build-system}:
6138 @item glib-or-gtk-wrap
6139 The phase @code{glib-or-gtk-wrap} ensures that programs in
6140 @file{bin/} are able to find GLib ``schemas'' and
6141 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6142 modules}. This is achieved by wrapping the programs in launch scripts
6143 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
6144 environment variables.
6146 It is possible to exclude specific package outputs from that wrapping
6147 process by listing their names in the
6148 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6149 when an output is known not to contain any GLib or GTK+ binaries, and
6150 where wrapping would gratuitously add a dependency of that output on
6153 @item glib-or-gtk-compile-schemas
6154 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6155 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6156 GSettings schemas} of GLib are compiled. Compilation is performed by the
6157 @command{glib-compile-schemas} program. It is provided by the package
6158 @code{glib:bin} which is automatically imported by the build system.
6159 The @code{glib} package providing @command{glib-compile-schemas} can be
6160 specified with the @code{#:glib} parameter.
6163 Both phases are executed after the @code{install} phase.
6166 @defvr {Scheme Variable} guile-build-system
6167 This build system is for Guile packages that consist exclusively of Scheme
6168 code and that are so lean that they don't even have a makefile, let alone a
6169 @file{configure} script. It compiles Scheme code using @command{guild
6170 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6171 installs the @file{.scm} and @file{.go} files in the right place. It also
6172 installs documentation.
6174 This build system supports cross-compilation by using the @code{--target}
6175 option of @command{guild compile}.
6177 Packages built with @code{guile-build-system} must provide a Guile package in
6178 their @code{native-inputs} field.
6181 @defvr {Scheme Variable} julia-build-system
6182 This variable is exported by @code{(guix build-system julia)}. It implements
6183 the build procedure used by @uref{https://julialang.org/, julia} packages,
6184 which essentially is similar to running @command{julia -e 'using Pkg;
6185 Pkg.add(package)'} in an environment where @code{JULIA_LOAD_PATH} contains the
6186 paths to all Julia package inputs. Tests are run not run.
6188 Julia packages require the source @code{file-name} to be the real name of the
6189 package, correctly capitalized.
6191 For packages requiring shared library dependencies, you may need to write the
6192 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6193 variable = /gnu/store/library.so} for each dependency, plus a void function
6194 @code{check_deps() = nothing}.
6196 Some older packages that aren't using @file{Package.toml} yet, will require
6197 this file to be created, too. The function @code{julia-create-package-toml}
6198 helps creating the file. You need to pass the outputs and the source of the
6199 package, it's name (the same as the @code{file-name} parameter), the package
6200 uuid, the package version, and a list of dependencies specified by their name
6204 @defvr {Scheme Variable} minify-build-system
6205 This variable is exported by @code{(guix build-system minify)}. It
6206 implements a minification procedure for simple JavaScript packages.
6208 It adds @code{uglify-js} to the set of inputs and uses it to compress
6209 all JavaScript files in the @file{src} directory. A different minifier
6210 package can be specified with the @code{#:uglify-js} parameter, but it
6211 is expected that the package writes the minified code to the standard
6214 When the input JavaScript files are not all located in the @file{src}
6215 directory, the parameter @code{#:javascript-files} can be used to
6216 specify a list of file names to feed to the minifier.
6219 @defvr {Scheme Variable} ocaml-build-system
6220 This variable is exported by @code{(guix build-system ocaml)}. It implements
6221 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6222 of choosing the correct set of commands to run for each package. OCaml
6223 packages can expect many different commands to be run. This build system will
6226 When the package has a @file{setup.ml} file present at the top-level, it will
6227 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6228 @code{ocaml setup.ml -install}. The build system will assume that this file
6229 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6230 care of setting the prefix and enabling tests if they are not disabled. You
6231 can pass configure and build flags with the @code{#:configure-flags} and
6232 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6233 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6234 bypass this system in the build and install phases.
6236 When the package has a @file{configure} file, it is assumed that it is a
6237 hand-made configure script that requires a different argument format than
6238 in the @code{gnu-build-system}. You can add more flags with the
6239 @code{#:configure-flags} key.
6241 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6242 @code{#t}), it will be used and more flags can be passed to the build and
6243 install phases with the @code{#:make-flags} key.
6245 Finally, some packages do not have these files and use a somewhat standard
6246 location for its build system. In that case, the build system will run
6247 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6248 providing the path to the required findlib module. Additional flags can
6249 be passed via the @code{#:build-flags} key. Install is taken care of by
6250 @command{opam-installer}. In this case, the @code{opam} package must
6251 be added to the @code{native-inputs} field of the package definition.
6253 Note that most OCaml packages assume they will be installed in the same
6254 directory as OCaml, which is not what we want in guix. In particular, they
6255 will install @file{.so} files in their module's directory, which is usually
6256 fine because it is in the OCaml compiler directory. In guix though, these
6257 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6258 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6259 @file{.so} libraries should be installed.
6262 @defvr {Scheme Variable} python-build-system
6263 This variable is exported by @code{(guix build-system python)}. It
6264 implements the more or less standard build procedure used by Python
6265 packages, which consists in running @code{python setup.py build} and
6266 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6268 For packages that install stand-alone Python programs under @code{bin/},
6269 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6270 environment variable points to all the Python libraries they depend on.
6272 Which Python package is used to perform the build can be specified with
6273 the @code{#:python} parameter. This is a useful way to force a package
6274 to be built for a specific version of the Python interpreter, which
6275 might be necessary if the package is only compatible with a single
6276 interpreter version.
6278 By default guix calls @code{setup.py} under control of
6279 @code{setuptools}, much like @command{pip} does. Some packages are not
6280 compatible with setuptools (and pip), thus you can disable this by
6281 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6284 @defvr {Scheme Variable} perl-build-system
6285 This variable is exported by @code{(guix build-system perl)}. It
6286 implements the standard build procedure for Perl packages, which either
6287 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6288 followed by @code{Build} and @code{Build install}; or in running
6289 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6290 @code{make} and @code{make install}, depending on which of
6291 @code{Build.PL} or @code{Makefile.PL} is present in the package
6292 distribution. Preference is given to the former if both @code{Build.PL}
6293 and @code{Makefile.PL} exist in the package distribution. This
6294 preference can be reversed by specifying @code{#t} for the
6295 @code{#:make-maker?} parameter.
6297 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6298 passes flags specified by the @code{#:make-maker-flags} or
6299 @code{#:module-build-flags} parameter, respectively.
6301 Which Perl package is used can be specified with @code{#:perl}.
6304 @defvr {Scheme Variable} r-build-system
6305 This variable is exported by @code{(guix build-system r)}. It
6306 implements the build procedure used by @uref{https://r-project.org, R}
6307 packages, which essentially is little more than running @code{R CMD
6308 INSTALL --library=/gnu/store/@dots{}} in an environment where
6309 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6310 are run after installation using the R function
6311 @code{tools::testInstalledPackage}.
6314 @defvr {Scheme Variable} rakudo-build-system
6315 This variable is exported by @code{(guix build-system rakudo)}. It
6316 implements the build procedure used by @uref{https://rakudo.org/,
6317 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6318 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6319 installs the binaries, library files and the resources, as well as wrap
6320 the files under the @code{bin/} directory. Tests can be skipped by
6321 passing @code{#f} to the @code{tests?} parameter.
6323 Which rakudo package is used can be specified with @code{rakudo}.
6324 Which perl6-tap-harness package used for the tests can be specified with
6325 @code{#:prove6} or removed by passing @code{#f} to the
6326 @code{with-prove6?} parameter.
6327 Which perl6-zef package used for tests and installing can be specified
6328 with @code{#:zef} or removed by passing @code{#f} to the
6329 @code{with-zef?} parameter.
6332 @defvr {Scheme Variable} texlive-build-system
6333 This variable is exported by @code{(guix build-system texlive)}. It is
6334 used to build TeX packages in batch mode with a specified engine. The
6335 build system sets the @code{TEXINPUTS} variable to find all TeX source
6336 files in the inputs.
6338 By default it runs @code{luatex} on all files ending on @code{ins}. A
6339 different engine and format can be specified with the
6340 @code{#:tex-format} argument. Different build targets can be specified
6341 with the @code{#:build-targets} argument, which expects a list of file
6342 names. The build system adds only @code{texlive-bin} and
6343 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6344 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6345 and @code{#:texlive-latex-base}, respectively.
6347 The @code{#:tex-directory} parameter tells the build system where to
6348 install the built files under the texmf tree.
6351 @defvr {Scheme Variable} ruby-build-system
6352 This variable is exported by @code{(guix build-system ruby)}. It
6353 implements the RubyGems build procedure used by Ruby packages, which
6354 involves running @code{gem build} followed by @code{gem install}.
6356 The @code{source} field of a package that uses this build system
6357 typically references a gem archive, since this is the format that Ruby
6358 developers use when releasing their software. The build system unpacks
6359 the gem archive, potentially patches the source, runs the test suite,
6360 repackages the gem, and installs it. Additionally, directories and
6361 tarballs may be referenced to allow building unreleased gems from Git or
6362 a traditional source release tarball.
6364 Which Ruby package is used can be specified with the @code{#:ruby}
6365 parameter. A list of additional flags to be passed to the @command{gem}
6366 command can be specified with the @code{#:gem-flags} parameter.
6369 @defvr {Scheme Variable} waf-build-system
6370 This variable is exported by @code{(guix build-system waf)}. It
6371 implements a build procedure around the @code{waf} script. The common
6372 phases---@code{configure}, @code{build}, and @code{install}---are
6373 implemented by passing their names as arguments to the @code{waf}
6376 The @code{waf} script is executed by the Python interpreter. Which
6377 Python package is used to run the script can be specified with the
6378 @code{#:python} parameter.
6381 @defvr {Scheme Variable} scons-build-system
6382 This variable is exported by @code{(guix build-system scons)}. It
6383 implements the build procedure used by the SCons software construction
6384 tool. This build system runs @code{scons} to build the package,
6385 @code{scons test} to run tests, and then @code{scons install} to install
6388 Additional flags to be passed to @code{scons} can be specified with the
6389 @code{#:scons-flags} parameter. The version of Python used to run SCons
6390 can be specified by selecting the appropriate SCons package with the
6391 @code{#:scons} parameter.
6394 @defvr {Scheme Variable} haskell-build-system
6395 This variable is exported by @code{(guix build-system haskell)}. It
6396 implements the Cabal build procedure used by Haskell packages, which
6397 involves running @code{runhaskell Setup.hs configure
6398 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6399 Instead of installing the package by running @code{runhaskell Setup.hs
6400 install}, to avoid trying to register libraries in the read-only
6401 compiler store directory, the build system uses @code{runhaskell
6402 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6403 addition, the build system generates the package documentation by
6404 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6405 is passed. Optional Haddock parameters can be passed with the help of
6406 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6407 not found, the build system looks for @code{Setup.lhs} instead.
6409 Which Haskell compiler is used can be specified with the @code{#:haskell}
6410 parameter which defaults to @code{ghc}.
6413 @defvr {Scheme Variable} dub-build-system
6414 This variable is exported by @code{(guix build-system dub)}. It
6415 implements the Dub build procedure used by D packages, which
6416 involves running @code{dub build} and @code{dub run}.
6417 Installation is done by copying the files manually.
6419 Which D compiler is used can be specified with the @code{#:ldc}
6420 parameter which defaults to @code{ldc}.
6423 @defvr {Scheme Variable} emacs-build-system
6424 This variable is exported by @code{(guix build-system emacs)}. It
6425 implements an installation procedure similar to the packaging system
6426 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6428 It first creates the @code{@var{package}-autoloads.el} file, then it
6429 byte compiles all Emacs Lisp files. Differently from the Emacs
6430 packaging system, the Info documentation files are moved to the standard
6431 documentation directory and the @file{dir} file is deleted. Each
6432 package is installed in its own directory under
6433 @file{share/emacs/site-lisp/guix.d}.
6436 @defvr {Scheme Variable} font-build-system
6437 This variable is exported by @code{(guix build-system font)}. It
6438 implements an installation procedure for font packages where upstream
6439 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6440 need to be copied into place. It copies font files to standard
6441 locations in the output directory.
6444 @defvr {Scheme Variable} meson-build-system
6445 This variable is exported by @code{(guix build-system meson)}. It
6446 implements the build procedure for packages that use
6447 @url{https://mesonbuild.com, Meson} as their build system.
6449 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6450 of inputs, and they can be changed with the parameters @code{#:meson}
6451 and @code{#:ninja} if needed. The default Meson is
6452 @code{meson-for-build}, which is special because it doesn't clear the
6453 @code{RUNPATH} of binaries and libraries when they are installed.
6455 This build system is an extension of @var{gnu-build-system}, but with the
6456 following phases changed to some specific for Meson:
6461 The phase runs @code{meson} with the flags specified in
6462 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6463 @code{plain} unless something else is specified in @code{#:build-type}.
6466 The phase runs @code{ninja} to build the package in parallel by default, but
6467 this can be changed with @code{#:parallel-build?}.
6470 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6471 which is @code{"test"} by default.
6474 The phase runs @code{ninja install} and can not be changed.
6477 Apart from that, the build system also adds the following phases:
6482 This phase ensures that all binaries can find the libraries they need.
6483 It searches for required libraries in subdirectories of the package being
6484 built, and adds those to @code{RUNPATH} where needed. It also removes
6485 references to libraries left over from the build phase by
6486 @code{meson-for-build}, such as test dependencies, that aren't actually
6487 required for the program to run.
6489 @item glib-or-gtk-wrap
6490 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6491 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6493 @item glib-or-gtk-compile-schemas
6494 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6495 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6499 @defvr {Scheme Variable} linux-module-build-system
6500 @var{linux-module-build-system} allows building Linux kernel modules.
6502 @cindex build phases
6503 This build system is an extension of @var{gnu-build-system}, but with the
6504 following phases changed:
6509 This phase configures the environment so that the Linux kernel's Makefile
6510 can be used to build the external kernel module.
6513 This phase uses the Linux kernel's Makefile in order to build the external
6517 This phase uses the Linux kernel's Makefile in order to install the external
6521 It is possible and useful to specify the Linux kernel to use for building
6522 the module (in the "arguments" form of a package using the
6523 linux-module-build-system, use the key #:linux to specify it).
6526 @defvr {Scheme Variable} node-build-system
6527 This variable is exported by @code{(guix build-system node)}. It
6528 implements the build procedure used by @uref{http://nodejs.org,
6529 Node.js}, which implements an approximation of the @code{npm install}
6530 command, followed by an @code{npm test} command.
6532 Which Node.js package is used to interpret the @code{npm} commands can
6533 be specified with the @code{#:node} parameter which defaults to
6537 Lastly, for packages that do not need anything as sophisticated, a
6538 ``trivial'' build system is provided. It is trivial in the sense that
6539 it provides basically no support: it does not pull any implicit inputs,
6540 and does not have a notion of build phases.
6542 @defvr {Scheme Variable} trivial-build-system
6543 This variable is exported by @code{(guix build-system trivial)}.
6545 This build system requires a @code{#:builder} argument. This argument
6546 must be a Scheme expression that builds the package output(s)---as
6547 with @code{build-expression->derivation} (@pxref{Derivations,
6548 @code{build-expression->derivation}}).
6558 Conceptually, the @dfn{store} is the place where derivations that have
6559 been built successfully are stored---by default, @file{/gnu/store}.
6560 Sub-directories in the store are referred to as @dfn{store items} or
6561 sometimes @dfn{store paths}. The store has an associated database that
6562 contains information such as the store paths referred to by each store
6563 path, and the list of @emph{valid} store items---results of successful
6564 builds. This database resides in @file{@var{localstatedir}/guix/db},
6565 where @var{localstatedir} is the state directory specified @i{via}
6566 @option{--localstatedir} at configure time, usually @file{/var}.
6568 The store is @emph{always} accessed by the daemon on behalf of its clients
6569 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6570 connect to the daemon over a Unix-domain socket, send requests to it,
6571 and read the result---these are remote procedure calls, or RPCs.
6574 Users must @emph{never} modify files under @file{/gnu/store} directly.
6575 This would lead to inconsistencies and break the immutability
6576 assumptions of Guix's functional model (@pxref{Introduction}).
6578 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6579 how to check the integrity of the store and attempt recovery from
6580 accidental modifications.
6583 The @code{(guix store)} module provides procedures to connect to the
6584 daemon, and to perform RPCs. These are described below. By default,
6585 @code{open-connection}, and thus all the @command{guix} commands,
6586 connect to the local daemon or to the URI specified by the
6587 @code{GUIX_DAEMON_SOCKET} environment variable.
6589 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6590 When set, the value of this variable should be a file name or a URI
6591 designating the daemon endpoint. When it is a file name, it denotes a
6592 Unix-domain socket to connect to. In addition to file names, the
6593 supported URI schemes are:
6598 These are for Unix-domain sockets.
6599 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6600 @file{/var/guix/daemon-socket/socket}.
6603 @cindex daemon, remote access
6604 @cindex remote access to the daemon
6605 @cindex daemon, cluster setup
6606 @cindex clusters, daemon setup
6607 These URIs denote connections over TCP/IP, without encryption nor
6608 authentication of the remote host. The URI must specify the host name
6609 and optionally a port number (by default port 44146 is used):
6612 guix://master.guix.example.org:1234
6615 This setup is suitable on local networks, such as clusters, where only
6616 trusted nodes may connect to the build daemon at
6617 @code{master.guix.example.org}.
6619 The @code{--listen} option of @command{guix-daemon} can be used to
6620 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6624 @cindex SSH access to build daemons
6625 These URIs allow you to connect to a remote daemon over
6626 SSH@footnote{This feature requires Guile-SSH (@pxref{Requirements}).}.
6627 A typical URL might look like this:
6630 ssh://charlie@@guix.example.org:22
6633 As for @command{guix copy}, the usual OpenSSH client configuration files
6634 are honored (@pxref{Invoking guix copy}).
6637 Additional URI schemes may be supported in the future.
6639 @c XXX: Remove this note when the protocol incurs fewer round trips
6640 @c and when (guix derivations) no longer relies on file system access.
6642 The ability to connect to remote build daemons is considered
6643 experimental as of @value{VERSION}. Please get in touch with us to
6644 share any problems or suggestions you may have (@pxref{Contributing}).
6648 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6649 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6650 @var{reserve-space?} is true, instruct it to reserve a little bit of
6651 extra space on the file system so that the garbage collector can still
6652 operate should the disk become full. Return a server object.
6654 @var{file} defaults to @code{%default-socket-path}, which is the normal
6655 location given the options that were passed to @command{configure}.
6658 @deffn {Scheme Procedure} close-connection @var{server}
6659 Close the connection to @var{server}.
6662 @defvr {Scheme Variable} current-build-output-port
6663 This variable is bound to a SRFI-39 parameter, which refers to the port
6664 where build and error logs sent by the daemon should be written.
6667 Procedures that make RPCs all take a server object as their first
6670 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6671 @cindex invalid store items
6672 Return @code{#t} when @var{path} designates a valid store item and
6673 @code{#f} otherwise (an invalid item may exist on disk but still be
6674 invalid, for instance because it is the result of an aborted or failed
6677 A @code{&store-protocol-error} condition is raised if @var{path} is not
6678 prefixed by the store directory (@file{/gnu/store}).
6681 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6682 Add @var{text} under file @var{name} in the store, and return its store
6683 path. @var{references} is the list of store paths referred to by the
6684 resulting store path.
6687 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6689 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6690 file names, or derivation/output pairs, using the specified
6691 @var{mode}---@code{(build-mode normal)} by default.
6694 Note that the @code{(guix monads)} module provides a monad as well as
6695 monadic versions of the above procedures, with the goal of making it
6696 more convenient to work with code that accesses the store (@pxref{The
6700 @i{This section is currently incomplete.}
6703 @section Derivations
6706 Low-level build actions and the environment in which they are performed
6707 are represented by @dfn{derivations}. A derivation contains the
6708 following pieces of information:
6712 The outputs of the derivation---derivations produce at least one file or
6713 directory in the store, but may produce more.
6716 @cindex build-time dependencies
6717 @cindex dependencies, build-time
6718 The inputs of the derivations---i.e., its build-time dependencies---which may
6719 be other derivations or plain files in the store (patches, build scripts,
6723 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
6726 The file name of a build script in the store, along with the arguments
6730 A list of environment variables to be defined.
6734 @cindex derivation path
6735 Derivations allow clients of the daemon to communicate build actions to
6736 the store. They exist in two forms: as an in-memory representation,
6737 both on the client- and daemon-side, and as files in the store whose
6738 name end in @code{.drv}---these files are referred to as @dfn{derivation
6739 paths}. Derivations paths can be passed to the @code{build-derivations}
6740 procedure to perform the build actions they prescribe (@pxref{The
6743 @cindex fixed-output derivations
6744 Operations such as file downloads and version-control checkouts for
6745 which the expected content hash is known in advance are modeled as
6746 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
6747 of a fixed-output derivation are independent of its inputs---e.g., a
6748 source code download produces the same result regardless of the download
6749 method and tools being used.
6752 @cindex run-time dependencies
6753 @cindex dependencies, run-time
6754 The outputs of derivations---i.e., the build results---have a set of
6755 @dfn{references}, as reported by the @code{references} RPC or the
6756 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
6757 are the set of run-time dependencies of the build results. References are a
6758 subset of the inputs of the derivation; this subset is automatically computed
6759 by the build daemon by scanning all the files in the outputs.
6761 The @code{(guix derivations)} module provides a representation of
6762 derivations as Scheme objects, along with procedures to create and
6763 otherwise manipulate derivations. The lowest-level primitive to create
6764 a derivation is the @code{derivation} procedure:
6766 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
6767 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6768 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
6769 [#:system (%current-system)] [#:references-graphs #f] @
6770 [#:allowed-references #f] [#:disallowed-references #f] @
6771 [#:leaked-env-vars #f] [#:local-build? #f] @
6772 [#:substitutable? #t] [#:properties '()]
6773 Build a derivation with the given arguments, and return the resulting
6774 @code{<derivation>} object.
6776 When @var{hash} and @var{hash-algo} are given, a
6777 @dfn{fixed-output derivation} is created---i.e., one whose result is
6778 known in advance, such as a file download. If, in addition,
6779 @var{recursive?} is true, then that fixed output may be an executable
6780 file or a directory and @var{hash} must be the hash of an archive
6781 containing this output.
6783 When @var{references-graphs} is true, it must be a list of file
6784 name/store path pairs. In that case, the reference graph of each store
6785 path is exported in the build environment in the corresponding file, in
6786 a simple text format.
6788 When @var{allowed-references} is true, it must be a list of store items
6789 or outputs that the derivation's output may refer to. Likewise,
6790 @var{disallowed-references}, if true, must be a list of things the
6791 outputs may @emph{not} refer to.
6793 When @var{leaked-env-vars} is true, it must be a list of strings
6794 denoting environment variables that are allowed to ``leak'' from the
6795 daemon's environment to the build environment. This is only applicable
6796 to fixed-output derivations---i.e., when @var{hash} is true. The main
6797 use is to allow variables such as @code{http_proxy} to be passed to
6798 derivations that download files.
6800 When @var{local-build?} is true, declare that the derivation is not a
6801 good candidate for offloading and should rather be built locally
6802 (@pxref{Daemon Offload Setup}). This is the case for small derivations
6803 where the costs of data transfers would outweigh the benefits.
6805 When @var{substitutable?} is false, declare that substitutes of the
6806 derivation's output should not be used (@pxref{Substitutes}). This is
6807 useful, for instance, when building packages that capture details of the
6808 host CPU instruction set.
6810 @var{properties} must be an association list describing ``properties'' of the
6811 derivation. It is kept as-is, uninterpreted, in the derivation.
6815 Here's an example with a shell script as its builder, assuming
6816 @var{store} is an open connection to the daemon, and @var{bash} points
6817 to a Bash executable in the store:
6820 (use-modules (guix utils)
6824 (let ((builder ; add the Bash script to the store
6825 (add-text-to-store store "my-builder.sh"
6826 "echo hello world > $out\n" '())))
6827 (derivation store "foo"
6828 bash `("-e" ,builder)
6829 #:inputs `((,bash) (,builder))
6830 #:env-vars '(("HOME" . "/homeless"))))
6831 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
6834 As can be guessed, this primitive is cumbersome to use directly. A
6835 better approach is to write build scripts in Scheme, of course! The
6836 best course of action for that is to write the build code as a
6837 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
6838 information, @pxref{G-Expressions}.
6840 Once upon a time, @code{gexp->derivation} did not exist and constructing
6841 derivations with build code written in Scheme was achieved with
6842 @code{build-expression->derivation}, documented below. This procedure
6843 is now deprecated in favor of the much nicer @code{gexp->derivation}.
6845 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
6846 @var{name} @var{exp} @
6847 [#:system (%current-system)] [#:inputs '()] @
6848 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6849 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
6850 [#:references-graphs #f] [#:allowed-references #f] @
6851 [#:disallowed-references #f] @
6852 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
6853 Return a derivation that executes Scheme expression @var{exp} as a
6854 builder for derivation @var{name}. @var{inputs} must be a list of
6855 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
6856 @code{"out"} is assumed. @var{modules} is a list of names of Guile
6857 modules from the current search path to be copied in the store,
6858 compiled, and made available in the load path during the execution of
6859 @var{exp}---e.g., @code{((guix build utils) (guix build
6860 gnu-build-system))}.
6862 @var{exp} is evaluated in an environment where @code{%outputs} is bound
6863 to a list of output/path pairs, and where @code{%build-inputs} is bound
6864 to a list of string/output-path pairs made from @var{inputs}.
6865 Optionally, @var{env-vars} is a list of string pairs specifying the name
6866 and value of environment variables visible to the builder. The builder
6867 terminates by passing the result of @var{exp} to @code{exit}; thus, when
6868 @var{exp} returns @code{#f}, the build is considered to have failed.
6870 @var{exp} is built using @var{guile-for-build} (a derivation). When
6871 @var{guile-for-build} is omitted or is @code{#f}, the value of the
6872 @code{%guile-for-build} fluid is used instead.
6874 See the @code{derivation} procedure for the meaning of
6875 @var{references-graphs}, @var{allowed-references},
6876 @var{disallowed-references}, @var{local-build?}, and
6877 @var{substitutable?}.
6881 Here's an example of a single-output derivation that creates a directory
6882 containing one file:
6885 (let ((builder '(let ((out (assoc-ref %outputs "out")))
6886 (mkdir out) ; create /gnu/store/@dots{}-goo
6887 (call-with-output-file (string-append out "/test")
6889 (display '(hello guix) p))))))
6890 (build-expression->derivation store "goo" builder))
6892 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
6896 @node The Store Monad
6897 @section The Store Monad
6901 The procedures that operate on the store described in the previous
6902 sections all take an open connection to the build daemon as their first
6903 argument. Although the underlying model is functional, they either have
6904 side effects or depend on the current state of the store.
6906 The former is inconvenient: the connection to the build daemon has to be
6907 carried around in all those functions, making it impossible to compose
6908 functions that do not take that parameter with functions that do. The
6909 latter can be problematic: since store operations have side effects
6910 and/or depend on external state, they have to be properly sequenced.
6912 @cindex monadic values
6913 @cindex monadic functions
6914 This is where the @code{(guix monads)} module comes in. This module
6915 provides a framework for working with @dfn{monads}, and a particularly
6916 useful monad for our uses, the @dfn{store monad}. Monads are a
6917 construct that allows two things: associating ``context'' with values
6918 (in our case, the context is the store), and building sequences of
6919 computations (here computations include accesses to the store). Values
6920 in a monad---values that carry this additional context---are called
6921 @dfn{monadic values}; procedures that return such values are called
6922 @dfn{monadic procedures}.
6924 Consider this ``normal'' procedure:
6927 (define (sh-symlink store)
6928 ;; Return a derivation that symlinks the 'bash' executable.
6929 (let* ((drv (package-derivation store bash))
6930 (out (derivation->output-path drv))
6931 (sh (string-append out "/bin/bash")))
6932 (build-expression->derivation store "sh"
6933 `(symlink ,sh %output))))
6936 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
6937 as a monadic function:
6940 (define (sh-symlink)
6941 ;; Same, but return a monadic value.
6942 (mlet %store-monad ((drv (package->derivation bash)))
6943 (gexp->derivation "sh"
6944 #~(symlink (string-append #$drv "/bin/bash")
6948 There are several things to note in the second version: the @code{store}
6949 parameter is now implicit and is ``threaded'' in the calls to the
6950 @code{package->derivation} and @code{gexp->derivation} monadic
6951 procedures, and the monadic value returned by @code{package->derivation}
6952 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
6954 As it turns out, the call to @code{package->derivation} can even be
6955 omitted since it will take place implicitly, as we will see later
6956 (@pxref{G-Expressions}):
6959 (define (sh-symlink)
6960 (gexp->derivation "sh"
6961 #~(symlink (string-append #$bash "/bin/bash")
6966 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
6967 @c for the funny quote.
6968 Calling the monadic @code{sh-symlink} has no effect. As someone once
6969 said, ``you exit a monad like you exit a building on fire: by running''.
6970 So, to exit the monad and get the desired effect, one must use
6971 @code{run-with-store}:
6974 (run-with-store (open-connection) (sh-symlink))
6975 @result{} /gnu/store/...-sh-symlink
6978 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
6979 new ``meta-commands'' to make it easier to deal with monadic procedures:
6980 @code{run-in-store}, and @code{enter-store-monad}. The former is used
6981 to ``run'' a single monadic value through the store:
6984 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
6985 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6988 The latter enters a recursive REPL, where all the return values are
6989 automatically run through the store:
6992 scheme@@(guile-user)> ,enter-store-monad
6993 store-monad@@(guile-user) [1]> (package->derivation hello)
6994 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6995 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
6996 $3 = "/gnu/store/@dots{}-foo"
6997 store-monad@@(guile-user) [1]> ,q
6998 scheme@@(guile-user)>
7002 Note that non-monadic values cannot be returned in the
7003 @code{store-monad} REPL.
7005 The main syntactic forms to deal with monads in general are provided by
7006 the @code{(guix monads)} module and are described below.
7008 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7009 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7013 @deffn {Scheme Syntax} return @var{val}
7014 Return a monadic value that encapsulates @var{val}.
7017 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7018 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7019 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7020 referred to as ``bind'', but that name denotes an unrelated procedure in
7021 Guile. Thus we use this somewhat cryptic symbol inherited from the
7022 Haskell language.}. There can be one @var{mproc} or several of them, as
7027 (with-monad %state-monad
7029 (lambda (x) (return (+ 1 x)))
7030 (lambda (x) (return (* 2 x)))))
7034 @result{} some-state
7038 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7040 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7042 Bind the variables @var{var} to the monadic values @var{mval} in
7043 @var{body}, which is a sequence of expressions. As with the bind
7044 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7045 value ``contained'' in @var{mval} and making @var{var} refer to that
7046 raw, non-monadic value within the scope of the @var{body}. The form
7047 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7048 @var{val}, as per @code{let}. The binding operations occur in sequence
7049 from left to right. The last expression of @var{body} must be a monadic
7050 expression, and its result will become the result of the @code{mlet} or
7051 @code{mlet*} when run in the @var{monad}.
7053 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7054 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7057 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7058 Bind @var{mexp} and the following monadic expressions in sequence,
7059 returning the result of the last expression. Every expression in the
7060 sequence must be a monadic expression.
7062 This is akin to @code{mlet}, except that the return values of the
7063 monadic expressions are ignored. In that sense, it is analogous to
7064 @code{begin}, but applied to monadic expressions.
7067 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7068 When @var{condition} is true, evaluate the sequence of monadic
7069 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7070 @var{condition} is false, return @code{*unspecified*} in the current
7071 monad. Every expression in the sequence must be a monadic expression.
7074 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7075 When @var{condition} is false, evaluate the sequence of monadic
7076 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7077 @var{condition} is true, return @code{*unspecified*} in the current
7078 monad. Every expression in the sequence must be a monadic expression.
7082 The @code{(guix monads)} module provides the @dfn{state monad}, which
7083 allows an additional value---the state---to be @emph{threaded} through
7084 monadic procedure calls.
7086 @defvr {Scheme Variable} %state-monad
7087 The state monad. Procedures in the state monad can access and change
7088 the state that is threaded.
7090 Consider the example below. The @code{square} procedure returns a value
7091 in the state monad. It returns the square of its argument, but also
7092 increments the current state value:
7096 (mlet %state-monad ((count (current-state)))
7097 (mbegin %state-monad
7098 (set-current-state (+ 1 count))
7101 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7106 When ``run'' through @var{%state-monad}, we obtain that additional state
7107 value, which is the number of @code{square} calls.
7110 @deffn {Monadic Procedure} current-state
7111 Return the current state as a monadic value.
7114 @deffn {Monadic Procedure} set-current-state @var{value}
7115 Set the current state to @var{value} and return the previous state as a
7119 @deffn {Monadic Procedure} state-push @var{value}
7120 Push @var{value} to the current state, which is assumed to be a list,
7121 and return the previous state as a monadic value.
7124 @deffn {Monadic Procedure} state-pop
7125 Pop a value from the current state and return it as a monadic value.
7126 The state is assumed to be a list.
7129 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7130 Run monadic value @var{mval} starting with @var{state} as the initial
7131 state. Return two values: the resulting value, and the resulting state.
7134 The main interface to the store monad, provided by the @code{(guix
7135 store)} module, is as follows.
7137 @defvr {Scheme Variable} %store-monad
7138 The store monad---an alias for @var{%state-monad}.
7140 Values in the store monad encapsulate accesses to the store. When its
7141 effect is needed, a value of the store monad must be ``evaluated'' by
7142 passing it to the @code{run-with-store} procedure (see below.)
7145 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7146 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7147 open store connection.
7150 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7151 Return as a monadic value the absolute file name in the store of the file
7152 containing @var{text}, a string. @var{references} is a list of store items that the
7153 resulting text file refers to; it defaults to the empty list.
7156 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7157 Return as a monadic value the absolute file name in the store of the file
7158 containing @var{data}, a bytevector. @var{references} is a list of store
7159 items that the resulting binary file refers to; it defaults to the empty list.
7162 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7163 [#:recursive? #t] [#:select? (const #t)]
7164 Return the name of @var{file} once interned in the store. Use
7165 @var{name} as its store name, or the basename of @var{file} if
7166 @var{name} is omitted.
7168 When @var{recursive?} is true, the contents of @var{file} are added
7169 recursively; if @var{file} designates a flat file and @var{recursive?}
7170 is true, its contents are added, and its permission bits are kept.
7172 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7173 @var{stat})} for each directory entry, where @var{file} is the entry's
7174 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7175 entries for which @var{select?} does not return true.
7177 The example below adds a file to the store, under two different names:
7180 (run-with-store (open-connection)
7181 (mlet %store-monad ((a (interned-file "README"))
7182 (b (interned-file "README" "LEGU-MIN")))
7183 (return (list a b))))
7185 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7190 The @code{(guix packages)} module exports the following package-related
7193 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7194 [#:system (%current-system)] [#:target #f] @
7197 value in the absolute file name of @var{file} within the @var{output}
7198 directory of @var{package}. When @var{file} is omitted, return the name
7199 of the @var{output} directory of @var{package}. When @var{target} is
7200 true, use it as a cross-compilation target triplet.
7203 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7204 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7205 @var{target} [@var{system}]
7206 Monadic version of @code{package-derivation} and
7207 @code{package-cross-derivation} (@pxref{Defining Packages}).
7212 @section G-Expressions
7214 @cindex G-expression
7215 @cindex build code quoting
7216 So we have ``derivations'', which represent a sequence of build actions
7217 to be performed to produce an item in the store (@pxref{Derivations}).
7218 These build actions are performed when asking the daemon to actually
7219 build the derivations; they are run by the daemon in a container
7220 (@pxref{Invoking guix-daemon}).
7222 @cindex strata of code
7223 It should come as no surprise that we like to write these build actions
7224 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7225 code@footnote{The term @dfn{stratum} in this context was coined by
7226 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7227 Kiselyov, who has written insightful
7228 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7229 on this topic}, refers to this kind of code generation as
7230 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7231 to the daemon, etc.---and the ``build code''---code that actually
7232 performs build actions, such as making directories, invoking
7233 @command{make}, etc.
7235 To describe a derivation and its build actions, one typically needs to
7236 embed build code inside host code. It boils down to manipulating build
7237 code as data, and the homoiconicity of Scheme---code has a direct
7238 representation as data---comes in handy for that. But we need more than
7239 the normal @code{quasiquote} mechanism in Scheme to construct build
7242 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7243 S-expressions adapted to build expressions. G-expressions, or
7244 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7245 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7246 @code{#$}, and @code{#$@@}), which are comparable to
7247 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7248 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7249 GNU Guile Reference Manual}). However, there are major differences:
7253 Gexps are meant to be written to a file and run or manipulated by other
7257 When a high-level object such as a package or derivation is unquoted
7258 inside a gexp, the result is as if its output file name had been
7262 Gexps carry information about the packages or derivations they refer to,
7263 and these dependencies are automatically added as inputs to the build
7264 processes that use them.
7267 @cindex lowering, of high-level objects in gexps
7268 This mechanism is not limited to package and derivation
7269 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7270 derivations or files in the store can be defined,
7271 such that these objects can also be inserted
7272 into gexps. For example, a useful type of high-level objects that can be
7273 inserted in a gexp is ``file-like objects'', which make it easy to
7274 add files to the store and to refer to them in
7275 derivations and such (see @code{local-file} and @code{plain-file}
7278 To illustrate the idea, here is an example of a gexp:
7285 (symlink (string-append #$coreutils "/bin/ls")
7289 This gexp can be passed to @code{gexp->derivation}; we obtain a
7290 derivation that builds a directory containing exactly one symlink to
7291 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7294 (gexp->derivation "the-thing" build-exp)
7297 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7298 substituted to the reference to the @var{coreutils} package in the
7299 actual build code, and @var{coreutils} is automatically made an input to
7300 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7301 output)}) is replaced by a string containing the directory name of the
7302 output of the derivation.
7304 @cindex cross compilation
7305 In a cross-compilation context, it is useful to distinguish between
7306 references to the @emph{native} build of a package---that can run on the
7307 host---versus references to cross builds of a package. To that end, the
7308 @code{#+} plays the same role as @code{#$}, but is a reference to a
7309 native package build:
7312 (gexp->derivation "vi"
7315 (system* (string-append #+coreutils "/bin/ln")
7317 (string-append #$emacs "/bin/emacs")
7318 (string-append #$output "/bin/vi")))
7319 #:target "mips64el-linux-gnu")
7323 In the example above, the native build of @var{coreutils} is used, so
7324 that @command{ln} can actually run on the host; but then the
7325 cross-compiled build of @var{emacs} is referenced.
7327 @cindex imported modules, for gexps
7328 @findex with-imported-modules
7329 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7330 able to use certain Guile modules from the ``host environment'' in the
7331 gexp, so those modules should be imported in the ``build environment''.
7332 The @code{with-imported-modules} form allows you to express that:
7335 (let ((build (with-imported-modules '((guix build utils))
7337 (use-modules (guix build utils))
7338 (mkdir-p (string-append #$output "/bin"))))))
7339 (gexp->derivation "empty-dir"
7342 (display "success!\n")
7347 In this example, the @code{(guix build utils)} module is automatically
7348 pulled into the isolated build environment of our gexp, such that
7349 @code{(use-modules (guix build utils))} works as expected.
7351 @cindex module closure
7352 @findex source-module-closure
7353 Usually you want the @emph{closure} of the module to be imported---i.e.,
7354 the module itself and all the modules it depends on---rather than just
7355 the module; failing to do that, attempts to use the module will fail
7356 because of missing dependent modules. The @code{source-module-closure}
7357 procedure computes the closure of a module by looking at its source file
7358 headers, which comes in handy in this case:
7361 (use-modules (guix modules)) ;for 'source-module-closure'
7363 (with-imported-modules (source-module-closure
7364 '((guix build utils)
7366 (gexp->derivation "something-with-vms"
7368 (use-modules (guix build utils)
7373 @cindex extensions, for gexps
7374 @findex with-extensions
7375 In the same vein, sometimes you want to import not just pure-Scheme
7376 modules, but also ``extensions'' such as Guile bindings to C libraries
7377 or other ``full-blown'' packages. Say you need the @code{guile-json}
7378 package available on the build side, here's how you would do it:
7381 (use-modules (gnu packages guile)) ;for 'guile-json'
7383 (with-extensions (list guile-json)
7384 (gexp->derivation "something-with-json"
7386 (use-modules (json))
7390 The syntactic form to construct gexps is summarized below.
7392 @deffn {Scheme Syntax} #~@var{exp}
7393 @deffnx {Scheme Syntax} (gexp @var{exp})
7394 Return a G-expression containing @var{exp}. @var{exp} may contain one
7395 or more of the following forms:
7399 @itemx (ungexp @var{obj})
7400 Introduce a reference to @var{obj}. @var{obj} may have one of the
7401 supported types, for example a package or a
7402 derivation, in which case the @code{ungexp} form is replaced by its
7403 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7405 If @var{obj} is a list, it is traversed and references to supported
7406 objects are substituted similarly.
7408 If @var{obj} is another gexp, its contents are inserted and its
7409 dependencies are added to those of the containing gexp.
7411 If @var{obj} is another kind of object, it is inserted as is.
7413 @item #$@var{obj}:@var{output}
7414 @itemx (ungexp @var{obj} @var{output})
7415 This is like the form above, but referring explicitly to the
7416 @var{output} of @var{obj}---this is useful when @var{obj} produces
7417 multiple outputs (@pxref{Packages with Multiple Outputs}).
7420 @itemx #+@var{obj}:output
7421 @itemx (ungexp-native @var{obj})
7422 @itemx (ungexp-native @var{obj} @var{output})
7423 Same as @code{ungexp}, but produces a reference to the @emph{native}
7424 build of @var{obj} when used in a cross compilation context.
7426 @item #$output[:@var{output}]
7427 @itemx (ungexp output [@var{output}])
7428 Insert a reference to derivation output @var{output}, or to the main
7429 output when @var{output} is omitted.
7431 This only makes sense for gexps passed to @code{gexp->derivation}.
7434 @itemx (ungexp-splicing @var{lst})
7435 Like the above, but splices the contents of @var{lst} inside the
7439 @itemx (ungexp-native-splicing @var{lst})
7440 Like the above, but refers to native builds of the objects listed in
7445 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7446 of the @code{gexp?} type (see below.)
7449 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7450 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7451 in their execution environment.
7453 Each item in @var{modules} can be the name of a module, such as
7454 @code{(guix build utils)}, or it can be a module name, followed by an
7455 arrow, followed by a file-like object:
7458 `((guix build utils)
7460 ((guix config) => ,(scheme-file "config.scm"
7461 #~(define-module @dots{}))))
7465 In the example above, the first two modules are taken from the search
7466 path, and the last one is created from the given file-like object.
7468 This form has @emph{lexical} scope: it has an effect on the gexps
7469 directly defined in @var{body}@dots{}, but not on those defined, say, in
7470 procedures called from @var{body}@dots{}.
7473 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7474 Mark the gexps defined in @var{body}@dots{} as requiring
7475 @var{extensions} in their build and execution environment.
7476 @var{extensions} is typically a list of package objects such as those
7477 defined in the @code{(gnu packages guile)} module.
7479 Concretely, the packages listed in @var{extensions} are added to the
7480 load path while compiling imported modules in @var{body}@dots{}; they
7481 are also added to the load path of the gexp returned by
7485 @deffn {Scheme Procedure} gexp? @var{obj}
7486 Return @code{#t} if @var{obj} is a G-expression.
7489 G-expressions are meant to be written to disk, either as code building
7490 some derivation, or as plain files in the store. The monadic procedures
7491 below allow you to do that (@pxref{The Store Monad}, for more
7492 information about monads.)
7494 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7495 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7496 [#:hash #f] [#:hash-algo #f] @
7497 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7498 [#:module-path @var{%load-path}] @
7499 [#:effective-version "2.2"] @
7500 [#:references-graphs #f] [#:allowed-references #f] @
7501 [#:disallowed-references #f] @
7502 [#:leaked-env-vars #f] @
7503 [#:script-name (string-append @var{name} "-builder")] @
7504 [#:deprecation-warnings #f] @
7505 [#:local-build? #f] [#:substitutable? #t] @
7506 [#:properties '()] [#:guile-for-build #f]
7507 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7508 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7509 stored in a file called @var{script-name}. When @var{target} is true,
7510 it is used as the cross-compilation target triplet for packages referred
7513 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7515 make @var{modules} available in the evaluation context of @var{exp};
7516 @var{modules} is a list of names of Guile modules searched in
7517 @var{module-path} to be copied in the store, compiled, and made available in
7518 the load path during the execution of @var{exp}---e.g., @code{((guix
7519 build utils) (guix build gnu-build-system))}.
7521 @var{effective-version} determines the string to use when adding extensions of
7522 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7524 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7527 When @var{references-graphs} is true, it must be a list of tuples of one of the
7531 (@var{file-name} @var{package})
7532 (@var{file-name} @var{package} @var{output})
7533 (@var{file-name} @var{derivation})
7534 (@var{file-name} @var{derivation} @var{output})
7535 (@var{file-name} @var{store-item})
7538 The right-hand-side of each element of @var{references-graphs} is automatically made
7539 an input of the build process of @var{exp}. In the build environment, each
7540 @var{file-name} contains the reference graph of the corresponding item, in a simple
7543 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7544 In the latter case, the list denotes store items that the result is allowed to
7545 refer to. Any reference to another store item will lead to a build error.
7546 Similarly for @var{disallowed-references}, which can list items that must not be
7547 referenced by the outputs.
7549 @var{deprecation-warnings} determines whether to show deprecation warnings while
7550 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7552 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7555 @cindex file-like objects
7556 The @code{local-file}, @code{plain-file}, @code{computed-file},
7557 @code{program-file}, and @code{scheme-file} procedures below return
7558 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7559 these objects lead to a file in the store. Consider this G-expression:
7562 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7563 #$(local-file "/tmp/my-nscd.conf"))
7566 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7567 to the store. Once expanded, for instance @i{via}
7568 @code{gexp->derivation}, the G-expression refers to that copy under
7569 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7570 does not have any effect on what the G-expression does.
7571 @code{plain-file} can be used similarly; it differs in that the file
7572 content is directly passed as a string.
7574 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7575 [#:recursive? #f] [#:select? (const #t)]
7576 Return an object representing local file @var{file} to add to the store; this
7577 object can be used in a gexp. If @var{file} is a relative file name, it is looked
7578 up relative to the source file where this form appears. @var{file} will be added to
7579 the store under @var{name}--by default the base name of @var{file}.
7581 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7582 designates a flat file and @var{recursive?} is true, its contents are added, and its
7583 permission bits are kept.
7585 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7586 @var{stat})} for each directory entry, where @var{file} is the entry's
7587 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7588 entries for which @var{select?} does not return true.
7590 This is the declarative counterpart of the @code{interned-file} monadic
7591 procedure (@pxref{The Store Monad, @code{interned-file}}).
7594 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7595 Return an object representing a text file called @var{name} with the given
7596 @var{content} (a string or a bytevector) to be added to the store.
7598 This is the declarative counterpart of @code{text-file}.
7601 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7602 [#:options '(#:local-build? #t)]
7603 Return an object representing the store item @var{name}, a file or
7604 directory computed by @var{gexp}. @var{options}
7605 is a list of additional arguments to pass to @code{gexp->derivation}.
7607 This is the declarative counterpart of @code{gexp->derivation}.
7610 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7611 [#:guile (default-guile)] [#:module-path %load-path] @
7612 [#:system (%current-system)] [#:target #f]
7613 Return an executable script @var{name} that runs @var{exp} using
7614 @var{guile}, with @var{exp}'s imported modules in its search path.
7615 Look up @var{exp}'s modules in @var{module-path}.
7617 The example below builds a script that simply invokes the @command{ls}
7621 (use-modules (guix gexp) (gnu packages base))
7623 (gexp->script "list-files"
7624 #~(execl #$(file-append coreutils "/bin/ls")
7628 When ``running'' it through the store (@pxref{The Store Monad,
7629 @code{run-with-store}}), we obtain a derivation that produces an
7630 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7633 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7635 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7639 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7640 [#:guile #f] [#:module-path %load-path]
7641 Return an object representing the executable store item @var{name} that
7642 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7643 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7645 This is the declarative counterpart of @code{gexp->script}.
7648 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7649 [#:set-load-path? #t] [#:module-path %load-path] @
7651 [#:guile (default-guile)]
7652 Return a derivation that builds a file @var{name} containing @var{exp}.
7653 When @var{splice?} is true, @var{exp} is considered to be a list of
7654 expressions that will be spliced in the resulting file.
7656 When @var{set-load-path?} is true, emit code in the resulting file to
7657 set @code{%load-path} and @code{%load-compiled-path} to honor
7658 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7661 The resulting file holds references to all the dependencies of @var{exp}
7662 or a subset thereof.
7665 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7666 Return an object representing the Scheme file @var{name} that contains
7669 This is the declarative counterpart of @code{gexp->file}.
7672 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7673 Return as a monadic value a derivation that builds a text file
7674 containing all of @var{text}. @var{text} may list, in addition to
7675 strings, objects of any type that can be used in a gexp: packages,
7676 derivations, local file objects, etc. The resulting store file holds
7677 references to all these.
7679 This variant should be preferred over @code{text-file} anytime the file
7680 to create will reference items from the store. This is typically the
7681 case when building a configuration file that embeds store file names,
7685 (define (profile.sh)
7686 ;; Return the name of a shell script in the store that
7687 ;; initializes the 'PATH' environment variable.
7688 (text-file* "profile.sh"
7689 "export PATH=" coreutils "/bin:"
7690 grep "/bin:" sed "/bin\n"))
7693 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7694 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7695 preventing them from being garbage-collected during its lifetime.
7698 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7699 Return an object representing store file @var{name} containing
7700 @var{text}. @var{text} is a sequence of strings and file-like objects,
7704 (mixed-text-file "profile"
7705 "export PATH=" coreutils "/bin:" grep "/bin")
7708 This is the declarative counterpart of @code{text-file*}.
7711 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7712 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7713 Each item in @var{files} must be a two-element list where the first element is the
7714 file name to use in the new directory, and the second element is a gexp
7715 denoting the target file. Here's an example:
7719 `(("hosts" ,(plain-file "hosts"
7720 "127.0.0.1 localhost"))
7721 ("bashrc" ,(plain-file "bashrc"
7722 "alias ls='ls --color=auto'"))))
7725 This yields an @code{etc} directory containing these two files.
7728 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
7729 Return a directory that is the union of @var{things}, where @var{things} is a list of
7730 file-like objects denoting directories. For example:
7733 (directory-union "guile+emacs" (list guile emacs))
7736 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
7739 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
7740 Return a file-like object that expands to the concatenation of @var{obj}
7741 and @var{suffix}, where @var{obj} is a lowerable object and each
7742 @var{suffix} is a string.
7744 As an example, consider this gexp:
7747 (gexp->script "run-uname"
7748 #~(system* #$(file-append coreutils
7752 The same effect could be achieved with:
7755 (gexp->script "run-uname"
7756 #~(system* (string-append #$coreutils
7760 There is one difference though: in the @code{file-append} case, the
7761 resulting script contains the absolute file name as a string, whereas in
7762 the second case, the resulting script contains a @code{(string-append
7763 @dots{})} expression to construct the file name @emph{at run time}.
7767 Of course, in addition to gexps embedded in ``host'' code, there are
7768 also modules containing build tools. To make it clear that they are
7769 meant to be used in the build stratum, these modules are kept in the
7770 @code{(guix build @dots{})} name space.
7772 @cindex lowering, of high-level objects in gexps
7773 Internally, high-level objects are @dfn{lowered}, using their compiler,
7774 to either derivations or store items. For instance, lowering a package
7775 yields a derivation, and lowering a @code{plain-file} yields a store
7776 item. This is achieved using the @code{lower-object} monadic procedure.
7778 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
7780 Return as a value in @var{%store-monad} the derivation or store item
7781 corresponding to @var{obj} for @var{system}, cross-compiling for
7782 @var{target} if @var{target} is true. @var{obj} must be an object that
7783 has an associated gexp compiler, such as a @code{<package>}.
7786 @node Invoking guix repl
7787 @section Invoking @command{guix repl}
7789 @cindex REPL, read-eval-print loop
7790 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
7791 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
7792 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
7793 command, @command{guix repl} guarantees that all the Guix modules and all its
7794 dependencies are available in the search path. You can use it this way:
7798 scheme@@(guile-user)> ,use (gnu packages base)
7799 scheme@@(guile-user)> coreutils
7800 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
7804 In addition, @command{guix repl} implements a simple machine-readable REPL
7805 protocol for use by @code{(guix inferior)}, a facility to interact with
7806 @dfn{inferiors}, separate processes running a potentially different revision
7809 The available options are as follows:
7812 @item --type=@var{type}
7813 @itemx -t @var{type}
7814 Start a REPL of the given @var{TYPE}, which can be one of the following:
7818 This is default, and it spawns a standard full-featured Guile REPL.
7820 Spawn a REPL that uses the machine-readable protocol. This is the protocol
7821 that the @code{(guix inferior)} module speaks.
7824 @item --listen=@var{endpoint}
7825 By default, @command{guix repl} reads from standard input and writes to
7826 standard output. When this option is passed, it will instead listen for
7827 connections on @var{endpoint}. Here are examples of valid options:
7830 @item --listen=tcp:37146
7831 Accept connections on localhost on port 37146.
7833 @item --listen=unix:/tmp/socket
7834 Accept connections on the Unix-domain socket @file{/tmp/socket}.
7838 @c *********************************************************************
7842 This section describes Guix command-line utilities. Some of them are
7843 primarily targeted at developers and users who write new package
7844 definitions, while others are more generally useful. They complement
7845 the Scheme programming interface of Guix in a convenient way.
7848 * Invoking guix build:: Building packages from the command line.
7849 * Invoking guix edit:: Editing package definitions.
7850 * Invoking guix download:: Downloading a file and printing its hash.
7851 * Invoking guix hash:: Computing the cryptographic hash of a file.
7852 * Invoking guix import:: Importing package definitions.
7853 * Invoking guix refresh:: Updating package definitions.
7854 * Invoking guix lint:: Finding errors in package definitions.
7855 * Invoking guix size:: Profiling disk usage.
7856 * Invoking guix graph:: Visualizing the graph of packages.
7857 * Invoking guix publish:: Sharing substitutes.
7858 * Invoking guix challenge:: Challenging substitute servers.
7859 * Invoking guix copy:: Copying to and from a remote store.
7860 * Invoking guix container:: Process isolation.
7861 * Invoking guix weather:: Assessing substitute availability.
7862 * Invoking guix processes:: Listing client processes.
7865 @node Invoking guix build
7866 @section Invoking @command{guix build}
7868 @cindex package building
7869 @cindex @command{guix build}
7870 The @command{guix build} command builds packages or derivations and
7871 their dependencies, and prints the resulting store paths. Note that it
7872 does not modify the user's profile---this is the job of the
7873 @command{guix package} command (@pxref{Invoking guix package}). Thus,
7874 it is mainly useful for distribution developers.
7876 The general syntax is:
7879 guix build @var{options} @var{package-or-derivation}@dots{}
7882 As an example, the following command builds the latest versions of Emacs
7883 and of Guile, displays their build logs, and finally displays the
7884 resulting directories:
7887 guix build emacs guile
7890 Similarly, the following command builds all the available packages:
7893 guix build --quiet --keep-going \
7894 `guix package -A | cut -f1,2 --output-delimiter=@@`
7897 @var{package-or-derivation} may be either the name of a package found in
7898 the software distribution such as @code{coreutils} or
7899 @code{coreutils@@8.20}, or a derivation such as
7900 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
7901 package with the corresponding name (and optionally version) is searched
7902 for among the GNU distribution modules (@pxref{Package Modules}).
7904 Alternatively, the @code{--expression} option may be used to specify a
7905 Scheme expression that evaluates to a package; this is useful when
7906 disambiguating among several same-named packages or package variants is
7909 There may be zero or more @var{options}. The available options are
7910 described in the subsections below.
7913 * Common Build Options:: Build options for most commands.
7914 * Package Transformation Options:: Creating variants of packages.
7915 * Additional Build Options:: Options specific to 'guix build'.
7916 * Debugging Build Failures:: Real life packaging experience.
7919 @node Common Build Options
7920 @subsection Common Build Options
7922 A number of options that control the build process are common to
7923 @command{guix build} and other commands that can spawn builds, such as
7924 @command{guix package} or @command{guix archive}. These are the
7929 @item --load-path=@var{directory}
7930 @itemx -L @var{directory}
7931 Add @var{directory} to the front of the package module search path
7932 (@pxref{Package Modules}).
7934 This allows users to define their own packages and make them visible to
7935 the command-line tools.
7939 Keep the build tree of failed builds. Thus, if a build fails, its build
7940 tree is kept under @file{/tmp}, in a directory whose name is shown at
7941 the end of the build log. This is useful when debugging build issues.
7942 @xref{Debugging Build Failures}, for tips and tricks on how to debug
7945 This option has no effect when connecting to a remote daemon with a
7946 @code{guix://} URI (@pxref{The Store, the @code{GUIX_DAEMON_SOCKET}
7951 Keep going when some of the derivations fail to build; return only once
7952 all the builds have either completed or failed.
7954 The default behavior is to stop as soon as one of the specified
7955 derivations has failed.
7959 Do not build the derivations.
7961 @anchor{fallback-option}
7963 When substituting a pre-built binary fails, fall back to building
7964 packages locally (@pxref{Substitution Failure}).
7966 @item --substitute-urls=@var{urls}
7967 @anchor{client-substitute-urls}
7968 Consider @var{urls} the whitespace-separated list of substitute source
7969 URLs, overriding the default list of URLs of @command{guix-daemon}
7970 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
7972 This means that substitutes may be downloaded from @var{urls}, provided
7973 they are signed by a key authorized by the system administrator
7974 (@pxref{Substitutes}).
7976 When @var{urls} is the empty string, substitutes are effectively
7979 @item --no-substitutes
7980 Do not use substitutes for build products. That is, always build things
7981 locally instead of allowing downloads of pre-built binaries
7982 (@pxref{Substitutes}).
7985 Do not ``graft'' packages. In practice, this means that package updates
7986 available as grafts are not applied. @xref{Security Updates}, for more
7987 information on grafts.
7989 @item --rounds=@var{n}
7990 Build each derivation @var{n} times in a row, and raise an error if
7991 consecutive build results are not bit-for-bit identical.
7993 This is a useful way to detect non-deterministic builds processes.
7994 Non-deterministic build processes are a problem because they make it
7995 practically impossible for users to @emph{verify} whether third-party
7996 binaries are genuine. @xref{Invoking guix challenge}, for more.
7998 Note that, currently, the differing build results are not kept around,
7999 so you will have to manually investigate in case of an error---e.g., by
8000 stashing one of the build results with @code{guix archive --export}
8001 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8004 @item --no-build-hook
8005 Do not attempt to offload builds @i{via} the ``build hook'' of the daemon
8006 (@pxref{Daemon Offload Setup}). That is, always build things locally
8007 instead of offloading builds to remote machines.
8009 @item --max-silent-time=@var{seconds}
8010 When the build or substitution process remains silent for more than
8011 @var{seconds}, terminate it and report a build failure.
8013 By default, the daemon's setting is honored (@pxref{Invoking
8014 guix-daemon, @code{--max-silent-time}}).
8016 @item --timeout=@var{seconds}
8017 Likewise, when the build or substitution process lasts for more than
8018 @var{seconds}, terminate it and report a build failure.
8020 By default, the daemon's setting is honored (@pxref{Invoking
8021 guix-daemon, @code{--timeout}}).
8023 @c Note: This option is actually not part of %standard-build-options but
8024 @c most programs honor it.
8025 @cindex verbosity, of the command-line tools
8026 @cindex build logs, verbosity
8027 @item -v @var{level}
8028 @itemx --verbosity=@var{level}
8029 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8030 output is produced, 1 is for quiet output, and 2 shows all the build log
8031 output on standard error.
8033 @item --cores=@var{n}
8035 Allow the use of up to @var{n} CPU cores for the build. The special
8036 value @code{0} means to use as many CPU cores as available.
8038 @item --max-jobs=@var{n}
8040 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8041 guix-daemon, @code{--max-jobs}}, for details about this option and the
8042 equivalent @command{guix-daemon} option.
8044 @item --debug=@var{level}
8045 Produce debugging output coming from the build daemon. @var{level} must be an
8046 integer between 0 and 5; higher means more verbose output. Setting a level of
8047 4 or more may be helpful when debugging setup issues with the build daemon.
8051 Behind the scenes, @command{guix build} is essentially an interface to
8052 the @code{package-derivation} procedure of the @code{(guix packages)}
8053 module, and to the @code{build-derivations} procedure of the @code{(guix
8054 derivations)} module.
8056 In addition to options explicitly passed on the command line,
8057 @command{guix build} and other @command{guix} commands that support
8058 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
8060 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8061 Users can define this variable to a list of command line options that
8062 will automatically be used by @command{guix build} and other
8063 @command{guix} commands that can perform builds, as in the example
8067 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8070 These options are parsed independently, and the result is appended to
8071 the parsed command-line options.
8075 @node Package Transformation Options
8076 @subsection Package Transformation Options
8078 @cindex package variants
8079 Another set of command-line options supported by @command{guix build}
8080 and also @command{guix package} are @dfn{package transformation
8081 options}. These are options that make it possible to define @dfn{package
8082 variants}---for instance, packages built from different source code.
8083 This is a convenient way to create customized packages on the fly
8084 without having to type in the definitions of package variants
8085 (@pxref{Defining Packages}).
8089 @item --with-source=@var{source}
8090 @itemx --with-source=@var{package}=@var{source}
8091 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8092 Use @var{source} as the source of @var{package}, and @var{version} as
8094 @var{source} must be a file name or a URL, as for @command{guix
8095 download} (@pxref{Invoking guix download}).
8097 When @var{package} is omitted,
8098 it is taken to be the package name specified on the
8099 command line that matches the base of @var{source}---e.g.,
8100 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8101 package is @code{guile}.
8103 Likewise, when @var{version} is omitted, the version string is inferred from
8104 @var{source}; in the previous example, it is @code{2.0.10}.
8106 This option allows users to try out versions of packages other than the
8107 one provided by the distribution. The example below downloads
8108 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8109 the @code{ed} package:
8112 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8115 As a developer, @code{--with-source} makes it easy to test release
8119 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8122 @dots{} or to build from a checkout in a pristine environment:
8125 $ git clone git://git.sv.gnu.org/guix.git
8126 $ guix build guix --with-source=guix@@1.0=./guix
8129 @item --with-input=@var{package}=@var{replacement}
8130 Replace dependency on @var{package} by a dependency on
8131 @var{replacement}. @var{package} must be a package name, and
8132 @var{replacement} must be a package specification such as @code{guile}
8133 or @code{guile@@1.8}.
8135 For instance, the following command builds Guix, but replaces its
8136 dependency on the current stable version of Guile with a dependency on
8137 the legacy version of Guile, @code{guile@@2.0}:
8140 guix build --with-input=guile=guile@@2.0 guix
8143 This is a recursive, deep replacement. So in this example, both
8144 @code{guix} and its dependency @code{guile-json} (which also depends on
8145 @code{guile}) get rebuilt against @code{guile@@2.0}.
8147 This is implemented using the @code{package-input-rewriting} Scheme
8148 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8150 @item --with-graft=@var{package}=@var{replacement}
8151 This is similar to @code{--with-input} but with an important difference:
8152 instead of rebuilding the whole dependency chain, @var{replacement} is
8153 built and then @dfn{grafted} onto the binaries that were initially
8154 referring to @var{package}. @xref{Security Updates}, for more
8155 information on grafts.
8157 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8158 and all its dependencies, replacing references to the version of GnuTLS
8159 they currently refer to:
8162 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8165 This has the advantage of being much faster than rebuilding everything.
8166 But there is a caveat: it works if and only if @var{package} and
8167 @var{replacement} are strictly compatible---for example, if they provide
8168 a library, the application binary interface (ABI) of those libraries
8169 must be compatible. If @var{replacement} is somehow incompatible with
8170 @var{package}, then the resulting package may be unusable. Use with
8173 @item --with-git-url=@var{package}=@var{url}
8174 @cindex Git, using the latest commit
8175 @cindex latest commit, building
8176 Build @var{package} from the latest commit of the @code{master} branch of the
8177 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8180 For example, the following command builds the NumPy Python library against the
8181 latest commit of the master branch of Python itself:
8184 guix build python-numpy \
8185 --with-git-url=python=https://github.com/python/cpython
8188 This option can also be combined with @code{--with-branch} or
8189 @code{--with-commit} (see below).
8191 @cindex continuous integration
8192 Obviously, since it uses the latest commit of the given branch, the result of
8193 such a command varies over time. Nevertheless it is a convenient way to
8194 rebuild entire software stacks against the latest commit of one or more
8195 packages. This is particularly useful in the context of continuous
8198 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8199 consecutive accesses to the same repository. You may want to clean it up once
8200 in a while to save disk space.
8202 @item --with-branch=@var{package}=@var{branch}
8203 Build @var{package} from the latest commit of @var{branch}. If the
8204 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8205 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8206 repository URL is taken from that @code{source}. Otherwise you have to use
8207 @code{--with-git-url} to specify the URL of the Git repository.
8209 For instance, the following command builds @code{guile-sqlite3} from the
8210 latest commit of its @code{master} branch, and then builds @code{guix} (which
8211 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8212 specific @code{guile-sqlite3} build:
8215 guix build --with-branch=guile-sqlite3=master cuirass
8218 @item --with-commit=@var{package}=@var{commit}
8219 This is similar to @code{--with-branch}, except that it builds from
8220 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8221 Git commit SHA1 identifier or a tag.
8224 @node Additional Build Options
8225 @subsection Additional Build Options
8227 The command-line options presented below are specific to @command{guix
8234 Build quietly, without displaying the build log; this is equivalent to
8235 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8236 (or similar) and can always be retrieved using the @option{--log-file} option.
8238 @item --file=@var{file}
8239 @itemx -f @var{file}
8240 Build the package, derivation, or other file-like object that the code within
8241 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8243 As an example, @var{file} might contain a package definition like this
8244 (@pxref{Defining Packages}):
8247 @include package-hello.scm
8250 @item --expression=@var{expr}
8251 @itemx -e @var{expr}
8252 Build the package or derivation @var{expr} evaluates to.
8254 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8255 guile-1.8)}, which unambiguously designates this specific variant of
8256 version 1.8 of Guile.
8258 Alternatively, @var{expr} may be a G-expression, in which case it is used
8259 as a build program passed to @code{gexp->derivation}
8260 (@pxref{G-Expressions}).
8262 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8263 (@pxref{The Store Monad}). The procedure must return a derivation as a
8264 monadic value, which is then passed through @code{run-with-store}.
8268 Build the source derivations of the packages, rather than the packages
8271 For instance, @code{guix build -S gcc} returns something like
8272 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8275 The returned source tarball is the result of applying any patches and
8276 code snippets specified in the package @code{origin} (@pxref{Defining
8280 Fetch and return the source of @var{package-or-derivation} and all their
8281 dependencies, recursively. This is a handy way to obtain a local copy
8282 of all the source code needed to build @var{packages}, allowing you to
8283 eventually build them even without network access. It is an extension
8284 of the @code{--source} option and can accept one of the following
8285 optional argument values:
8289 This value causes the @code{--sources} option to behave in the same way
8290 as the @code{--source} option.
8293 Build the source derivations of all packages, including any source that
8294 might be listed as @code{inputs}. This is the default value.
8297 $ guix build --sources tzdata
8298 The following derivations will be built:
8299 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8300 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8304 Build the source derivations of all packages, as well of all transitive
8305 inputs to the packages. This can be used e.g.@: to
8306 prefetch package source for later offline building.
8309 $ guix build --sources=transitive tzdata
8310 The following derivations will be built:
8311 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8312 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8313 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8314 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8315 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8316 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8322 @item --system=@var{system}
8323 @itemx -s @var{system}
8324 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8325 the system type of the build host. The @command{guix build} command allows
8326 you to repeat this option several times, in which case it builds for all the
8327 specified systems; other commands ignore extraneous @option{-s} options.
8330 The @code{--system} flag is for @emph{native} compilation and must not
8331 be confused with cross-compilation. See @code{--target} below for
8332 information on cross-compilation.
8335 An example use of this is on Linux-based systems, which can emulate
8336 different personalities. For instance, passing
8337 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8338 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8339 to build packages in a complete 32-bit environment.
8342 Building for an @code{armhf-linux} system is unconditionally enabled on
8343 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8344 allow for this functionality, notably the ThunderX.
8347 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8348 is enabled (@pxref{Virtualization Services,
8349 @code{qemu-binfmt-service-type}}), you can build for any system for
8350 which a QEMU @code{binfmt_misc} handler is installed.
8352 Builds for a system other than that of the machine you are using can
8353 also be offloaded to a remote machine of the right architecture.
8354 @xref{Daemon Offload Setup}, for more information on offloading.
8356 @item --target=@var{triplet}
8357 @cindex cross-compilation
8358 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8359 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8360 configuration triplets,, autoconf, Autoconf}).
8362 @anchor{build-check}
8364 @cindex determinism, checking
8365 @cindex reproducibility, checking
8366 Rebuild @var{package-or-derivation}, which are already available in the
8367 store, and raise an error if the build results are not bit-for-bit
8370 This mechanism allows you to check whether previously installed
8371 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8372 of a package is deterministic. @xref{Invoking guix challenge}, for more
8373 background information and tools.
8375 When used in conjunction with @option{--keep-failed}, the differing
8376 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8377 This makes it easy to look for differences between the two results.
8380 @cindex repairing store items
8381 @cindex corruption, recovering from
8382 Attempt to repair the specified store items, if they are corrupt, by
8383 re-downloading or rebuilding them.
8385 This operation is not atomic and thus restricted to @code{root}.
8389 Return the derivation paths, not the output paths, of the given
8392 @item --root=@var{file}
8393 @itemx -r @var{file}
8394 @cindex GC roots, adding
8395 @cindex garbage collector roots, adding
8396 Make @var{file} a symlink to the result, and register it as a garbage
8399 Consequently, the results of this @command{guix build} invocation are
8400 protected from garbage collection until @var{file} is removed. When
8401 that option is omitted, build results are eligible for garbage
8402 collection as soon as the build completes. @xref{Invoking guix gc}, for
8406 @cindex build logs, access
8407 Return the build log file names or URLs for the given
8408 @var{package-or-derivation}, or raise an error if build logs are
8411 This works regardless of how packages or derivations are specified. For
8412 instance, the following invocations are equivalent:
8415 guix build --log-file `guix build -d guile`
8416 guix build --log-file `guix build guile`
8417 guix build --log-file guile
8418 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8421 If a log is unavailable locally, and unless @code{--no-substitutes} is
8422 passed, the command looks for a corresponding log on one of the
8423 substitute servers (as specified with @code{--substitute-urls}.)
8425 So for instance, imagine you want to see the build log of GDB on MIPS,
8426 but you are actually on an @code{x86_64} machine:
8429 $ guix build --log-file gdb -s mips64el-linux
8430 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8433 You can freely access a huge library of build logs!
8436 @node Debugging Build Failures
8437 @subsection Debugging Build Failures
8439 @cindex build failures, debugging
8440 When defining a new package (@pxref{Defining Packages}), you will
8441 probably find yourself spending some time debugging and tweaking the
8442 build until it succeeds. To do that, you need to operate the build
8443 commands yourself in an environment as close as possible to the one the
8446 To that end, the first thing to do is to use the @option{--keep-failed}
8447 or @option{-K} option of @command{guix build}, which will keep the
8448 failed build tree in @file{/tmp} or whatever directory you specified as
8449 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8451 From there on, you can @command{cd} to the failed build tree and source
8452 the @file{environment-variables} file, which contains all the
8453 environment variable definitions that were in place when the build
8454 failed. So let's say you're debugging a build failure in package
8455 @code{foo}; a typical session would look like this:
8459 @dots{} @i{build fails}
8460 $ cd /tmp/guix-build-foo.drv-0
8461 $ source ./environment-variables
8465 Now, you can invoke commands as if you were the daemon (almost) and
8466 troubleshoot your build process.
8468 Sometimes it happens that, for example, a package's tests pass when you
8469 run them manually but they fail when the daemon runs them. This can
8470 happen because the daemon runs builds in containers where, unlike in our
8471 environment above, network access is missing, @file{/bin/sh} does not
8472 exist, etc. (@pxref{Build Environment Setup}).
8474 In such cases, you may need to run inspect the build process from within
8475 a container similar to the one the build daemon creates:
8480 $ cd /tmp/guix-build-foo.drv-0
8481 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8482 [env]# source ./environment-variables
8486 Here, @command{guix environment -C} creates a container and spawns a new
8487 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8488 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8489 the container, which would may find handy while debugging. The
8490 @option{--no-grafts} option makes sure we get the exact same
8491 environment, with ungrafted packages (@pxref{Security Updates}, for more
8494 To get closer to a container like that used by the build daemon, we can
8495 remove @file{/bin/sh}:
8501 (Don't worry, this is harmless: this is all happening in the throw-away
8502 container created by @command{guix environment}.)
8504 The @command{strace} command is probably not in the search path, but we
8508 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8511 In this way, not only you will have reproduced the environment variables
8512 the daemon uses, you will also be running the build process in a container
8513 similar to the one the daemon uses.
8516 @node Invoking guix edit
8517 @section Invoking @command{guix edit}
8519 @cindex @command{guix edit}
8520 @cindex package definition, editing
8521 So many packages, so many source files! The @command{guix edit} command
8522 facilitates the life of users and packagers by pointing their editor at
8523 the source file containing the definition of the specified packages.
8527 guix edit gcc@@4.9 vim
8531 launches the program specified in the @code{VISUAL} or in the
8532 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8535 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8536 have created your own packages on @code{GUIX_PACKAGE_PATH}
8537 (@pxref{Package Modules}), you will be able to edit the package
8538 recipes. In other cases, you will be able to examine the read-only recipes
8539 for packages currently in the store.
8542 @node Invoking guix download
8543 @section Invoking @command{guix download}
8545 @cindex @command{guix download}
8546 @cindex downloading package sources
8547 When writing a package definition, developers typically need to download
8548 a source tarball, compute its SHA256 hash, and write that
8549 hash in the package definition (@pxref{Defining Packages}). The
8550 @command{guix download} tool helps with this task: it downloads a file
8551 from the given URI, adds it to the store, and prints both its file name
8552 in the store and its SHA256 hash.
8554 The fact that the downloaded file is added to the store saves bandwidth:
8555 when the developer eventually tries to build the newly defined package
8556 with @command{guix build}, the source tarball will not have to be
8557 downloaded again because it is already in the store. It is also a
8558 convenient way to temporarily stash files, which may be deleted
8559 eventually (@pxref{Invoking guix gc}).
8561 The @command{guix download} command supports the same URIs as used in
8562 package definitions. In particular, it supports @code{mirror://} URIs.
8563 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8564 Guile bindings for GnuTLS are available in the user's environment; when
8565 they are not available, an error is raised. @xref{Guile Preparations,
8566 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8567 GnuTLS-Guile}, for more information.
8569 @command{guix download} verifies HTTPS server certificates by loading
8570 the certificates of X.509 authorities from the directory pointed to by
8571 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8572 Certificates}), unless @option{--no-check-certificate} is used.
8574 The following options are available:
8577 @item --format=@var{fmt}
8579 Write the hash in the format specified by @var{fmt}. For more
8580 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8582 @item --no-check-certificate
8583 Do not validate the X.509 certificates of HTTPS servers.
8585 When using this option, you have @emph{absolutely no guarantee} that you
8586 are communicating with the authentic server responsible for the given
8587 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8589 @item --output=@var{file}
8590 @itemx -o @var{file}
8591 Save the downloaded file to @var{file} instead of adding it to the
8595 @node Invoking guix hash
8596 @section Invoking @command{guix hash}
8598 @cindex @command{guix hash}
8599 The @command{guix hash} command computes the SHA256 hash of a file.
8600 It is primarily a convenience tool for anyone contributing to the
8601 distribution: it computes the cryptographic hash of a file, which can be
8602 used in the definition of a package (@pxref{Defining Packages}).
8604 The general syntax is:
8607 guix hash @var{option} @var{file}
8610 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8611 hash of data read from standard input. @command{guix hash} has the
8616 @item --format=@var{fmt}
8618 Write the hash in the format specified by @var{fmt}.
8620 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8621 (@code{hex} and @code{hexadecimal} can be used as well).
8623 If the @option{--format} option is not specified, @command{guix hash}
8624 will output the hash in @code{nix-base32}. This representation is used
8625 in the definitions of packages.
8629 Compute the hash on @var{file} recursively.
8631 In this case, the hash is computed on an archive containing @var{file},
8632 including its children if it is a directory. Some of the metadata of
8633 @var{file} is part of the archive; for instance, when @var{file} is a
8634 regular file, the hash is different depending on whether @var{file} is
8635 executable or not. Metadata such as time stamps has no impact on the
8636 hash (@pxref{Invoking guix archive}).
8637 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8642 When combined with @option{--recursive}, exclude version control system
8643 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8646 As an example, here is how you would compute the hash of a Git checkout,
8647 which is useful when using the @code{git-fetch} method (@pxref{origin
8651 $ git clone http://example.org/foo.git
8657 @node Invoking guix import
8658 @section Invoking @command{guix import}
8660 @cindex importing packages
8661 @cindex package import
8662 @cindex package conversion
8663 @cindex Invoking @command{guix import}
8664 The @command{guix import} command is useful for people who would like to
8665 add a package to the distribution with as little work as
8666 possible---a legitimate demand. The command knows of a few
8667 repositories from which it can ``import'' package metadata. The result
8668 is a package definition, or a template thereof, in the format we know
8669 (@pxref{Defining Packages}).
8671 The general syntax is:
8674 guix import @var{importer} @var{options}@dots{}
8677 @var{importer} specifies the source from which to import package
8678 metadata, and @var{options} specifies a package identifier and other
8679 options specific to @var{importer}.
8681 Some of the importers rely on the ability to run the @command{gpgv} command.
8682 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
8685 Currently, the available ``importers'' are:
8689 Import metadata for the given GNU package. This provides a template
8690 for the latest version of that GNU package, including the hash of its
8691 source tarball, and its canonical synopsis and description.
8693 Additional information such as the package dependencies and its
8694 license needs to be figured out manually.
8696 For example, the following command returns a package definition for
8700 guix import gnu hello
8703 Specific command-line options are:
8706 @item --key-download=@var{policy}
8707 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
8708 keys when verifying the package signature. @xref{Invoking guix
8709 refresh, @code{--key-download}}.
8714 Import metadata from the @uref{https://pypi.python.org/, Python Package
8715 Index}. Information is taken from the JSON-formatted description
8716 available at @code{pypi.python.org} and usually includes all the relevant
8717 information, including package dependencies. For maximum efficiency, it
8718 is recommended to install the @command{unzip} utility, so that the
8719 importer can unzip Python wheels and gather data from them.
8721 The command below imports metadata for the @code{itsdangerous} Python
8725 guix import pypi itsdangerous
8731 Traverse the dependency graph of the given upstream package recursively
8732 and generate package expressions for all those packages that are not yet
8738 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
8739 is taken from the JSON-formatted description available at
8740 @code{rubygems.org} and includes most relevant information, including
8741 runtime dependencies. There are some caveats, however. The metadata
8742 doesn't distinguish between synopses and descriptions, so the same string
8743 is used for both fields. Additionally, the details of non-Ruby
8744 dependencies required to build native extensions is unavailable and left
8745 as an exercise to the packager.
8747 The command below imports metadata for the @code{rails} Ruby package:
8750 guix import gem rails
8756 Traverse the dependency graph of the given upstream package recursively
8757 and generate package expressions for all those packages that are not yet
8763 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
8764 Information is taken from the JSON-formatted metadata provided through
8765 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
8766 relevant information, such as module dependencies. License information
8767 should be checked closely. If Perl is available in the store, then the
8768 @code{corelist} utility will be used to filter core modules out of the
8769 list of dependencies.
8771 The command command below imports metadata for the @code{Acme::Boolean}
8775 guix import cpan Acme::Boolean
8780 @cindex Bioconductor
8781 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
8782 central repository for the @uref{https://r-project.org, GNU@tie{}R
8783 statistical and graphical environment}.
8785 Information is extracted from the @code{DESCRIPTION} file of the package.
8787 The command command below imports metadata for the @code{Cairo}
8791 guix import cran Cairo
8794 When @code{--recursive} is added, the importer will traverse the
8795 dependency graph of the given upstream package recursively and generate
8796 package expressions for all those packages that are not yet in Guix.
8798 When @code{--archive=bioconductor} is added, metadata is imported from
8799 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
8800 packages for for the analysis and comprehension of high-throughput
8801 genomic data in bioinformatics.
8803 Information is extracted from the @code{DESCRIPTION} file contained in the
8806 The command below imports metadata for the @code{GenomicRanges}
8810 guix import cran --archive=bioconductor GenomicRanges
8813 Finally, you can also import R packages that have not yet been published on
8814 CRAN or Bioconductor as long as they are in a git repository. Use
8815 @code{--archive=git} followed by the URL of the git repository:
8818 guix import cran --archive=git https://github.com/immunogenomics/harmony
8824 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
8825 comprehensive TeX archive network for TeX packages that are part of the
8826 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
8828 Information about the package is obtained through the XML API provided
8829 by CTAN, while the source code is downloaded from the SVN repository of
8830 the Tex Live project. This is done because the CTAN does not keep
8833 The command command below imports metadata for the @code{fontspec}
8837 guix import texlive fontspec
8840 When @code{--archive=DIRECTORY} is added, the source code is downloaded
8841 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
8842 tree in the TeX Live SVN repository, but from the specified sibling
8843 directory under the same root.
8845 The command below imports metadata for the @code{ifxetex} package from
8846 CTAN while fetching the sources from the directory
8847 @file{texmf/source/generic}:
8850 guix import texlive --archive=generic ifxetex
8854 @cindex JSON, import
8855 Import package metadata from a local JSON file. Consider the following
8856 example package definition in JSON format:
8862 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
8863 "build-system": "gnu",
8864 "home-page": "https://www.gnu.org/software/hello/",
8865 "synopsis": "Hello, GNU world: An example GNU package",
8866 "description": "GNU Hello prints a greeting.",
8867 "license": "GPL-3.0+",
8868 "native-inputs": ["gettext"]
8872 The field names are the same as for the @code{<package>} record
8873 (@xref{Defining Packages}). References to other packages are provided
8874 as JSON lists of quoted package specification strings such as
8875 @code{guile} or @code{guile@@2.0}.
8877 The importer also supports a more explicit source definition using the
8878 common fields for @code{<origin>} records:
8884 "method": "url-fetch",
8885 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
8887 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
8894 The command below reads metadata from the JSON file @code{hello.json}
8895 and outputs a package expression:
8898 guix import json hello.json
8902 Import metadata from a local copy of the source of the
8903 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
8904 relies on the @command{nix-instantiate} command of
8905 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
8906 typically written in a mixture of Nix-language and Bash code. This
8907 command only imports the high-level package structure that is written in
8908 the Nix language. It normally includes all the basic fields of a
8911 When importing a GNU package, the synopsis and descriptions are replaced
8912 by their canonical upstream variant.
8914 Usually, you will first need to do:
8917 export NIX_REMOTE=daemon
8921 so that @command{nix-instantiate} does not try to open the Nix database.
8923 As an example, the command below imports the package definition of
8924 LibreOffice (more precisely, it imports the definition of the package
8925 bound to the @code{libreoffice} top-level attribute):
8928 guix import nix ~/path/to/nixpkgs libreoffice
8933 Import metadata from the Haskell community's central package archive
8934 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
8935 Cabal files and includes all the relevant information, including package
8938 Specific command-line options are:
8943 Read a Cabal file from standard input.
8944 @item --no-test-dependencies
8946 Do not include dependencies required only by the test suites.
8947 @item --cabal-environment=@var{alist}
8948 @itemx -e @var{alist}
8949 @var{alist} is a Scheme alist defining the environment in which the
8950 Cabal conditionals are evaluated. The accepted keys are: @code{os},
8951 @code{arch}, @code{impl} and a string representing the name of a flag.
8952 The value associated with a flag has to be either the symbol
8953 @code{true} or @code{false}. The value associated with other keys
8954 has to conform to the Cabal file format definition. The default value
8955 associated with the keys @code{os}, @code{arch} and @code{impl} is
8956 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
8959 Traverse the dependency graph of the given upstream package recursively
8960 and generate package expressions for all those packages that are not yet
8964 The command below imports metadata for the latest version of the
8965 @code{HTTP} Haskell package without including test dependencies and
8966 specifying the value of the flag @samp{network-uri} as @code{false}:
8969 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
8972 A specific package version may optionally be specified by following the
8973 package name by an at-sign and a version number as in the following example:
8976 guix import hackage mtl@@2.1.3.1
8981 The @code{stackage} importer is a wrapper around the @code{hackage} one.
8982 It takes a package name, looks up the package version included in a
8983 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
8984 release and uses the @code{hackage} importer to retrieve its metadata.
8985 Note that it is up to you to select an LTS release compatible with the
8986 GHC compiler used by Guix.
8988 Specific command-line options are:
8991 @item --no-test-dependencies
8993 Do not include dependencies required only by the test suites.
8994 @item --lts-version=@var{version}
8995 @itemx -l @var{version}
8996 @var{version} is the desired LTS release version. If omitted the latest
9000 Traverse the dependency graph of the given upstream package recursively
9001 and generate package expressions for all those packages that are not yet
9005 The command below imports metadata for the @code{HTTP} Haskell package
9006 included in the LTS Stackage release version 7.18:
9009 guix import stackage --lts-version=7.18 HTTP
9014 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9015 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9017 Specific command-line options are:
9020 @item --archive=@var{repo}
9021 @itemx -a @var{repo}
9022 @var{repo} identifies the archive repository from which to retrieve the
9023 information. Currently the supported repositories and their identifiers
9027 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9028 identifier. This is the default.
9030 Packages from @code{elpa.gnu.org} are signed with one of the keys
9031 contained in the GnuPG keyring at
9032 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9033 @code{emacs} package (@pxref{Package Installation, ELPA package
9034 signatures,, emacs, The GNU Emacs Manual}).
9037 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9038 @code{melpa-stable} identifier.
9041 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9047 Traverse the dependency graph of the given upstream package recursively
9048 and generate package expressions for all those packages that are not yet
9054 Import metadata from the crates.io Rust package repository
9055 @uref{https://crates.io, crates.io}, as in this example:
9058 guix import crate blake2-rfc
9061 The crate importer also allows you to specify a version string:
9064 guix import crate constant-time-eq@@0.1.0
9070 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9071 repository used by the OCaml community.
9074 The structure of the @command{guix import} code is modular. It would be
9075 useful to have more importers for other package formats, and your help
9076 is welcome here (@pxref{Contributing}).
9078 @node Invoking guix refresh
9079 @section Invoking @command{guix refresh}
9081 @cindex @command {guix refresh}
9082 The primary audience of the @command{guix refresh} command is developers
9083 of the GNU software distribution. By default, it reports any packages
9084 provided by the distribution that are outdated compared to the latest
9085 upstream version, like this:
9089 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9090 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9093 Alternately, one can specify packages to consider, in which case a
9094 warning is emitted for packages that lack an updater:
9097 $ guix refresh coreutils guile guile-ssh
9098 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9099 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9102 @command{guix refresh} browses the upstream repository of each package and determines
9103 the highest version number of the releases therein. The command
9104 knows how to update specific types of packages: GNU packages, ELPA
9105 packages, etc.---see the documentation for @option{--type} below. There
9106 are many packages, though, for which it lacks a method to determine
9107 whether a new upstream release is available. However, the mechanism is
9108 extensible, so feel free to get in touch with us to add a new method!
9113 Consider the packages specified, and all the packages upon which they depend.
9116 $ guix refresh --recursive coreutils
9117 gnu/packages/acl.scm:35:2: warning: no updater for acl
9118 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9119 gnu/packages/xml.scm:68:2: warning: no updater for expat
9120 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9126 Sometimes the upstream name differs from the package name used in Guix,
9127 and @command{guix refresh} needs a little help. Most updaters honor the
9128 @code{upstream-name} property in package definitions, which can be used
9132 (define-public network-manager
9134 (name "network-manager")
9136 (properties '((upstream-name . "NetworkManager")))))
9139 When passed @code{--update}, it modifies distribution source files to
9140 update the version numbers and source tarball hashes of those package
9141 recipes (@pxref{Defining Packages}). This is achieved by downloading
9142 each package's latest source tarball and its associated OpenPGP
9143 signature, authenticating the downloaded tarball against its signature
9144 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
9145 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
9148 key used to sign the tarball is missing from the user's keyring, an
9149 attempt is made to automatically retrieve it from a public key server;
9150 when this is successful, the key is added to the user's keyring; otherwise,
9151 @command{guix refresh} reports an error.
9153 The following options are supported:
9157 @item --expression=@var{expr}
9158 @itemx -e @var{expr}
9159 Consider the package @var{expr} evaluates to.
9161 This is useful to precisely refer to a package, as in this example:
9164 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9167 This command lists the dependents of the ``final'' libc (essentially all
9172 Update distribution source files (package recipes) in place. This is
9173 usually run from a checkout of the Guix source tree (@pxref{Running
9174 Guix Before It Is Installed}):
9177 $ ./pre-inst-env guix refresh -s non-core -u
9180 @xref{Defining Packages}, for more information on package definitions.
9182 @item --select=[@var{subset}]
9183 @itemx -s @var{subset}
9184 Select all the packages in @var{subset}, one of @code{core} or
9187 The @code{core} subset refers to all the packages at the core of the
9188 distribution---i.e., packages that are used to build ``everything
9189 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9190 changing one of these packages in the distribution entails a rebuild of
9191 all the others. Thus, such updates are an inconvenience to users in
9192 terms of build time or bandwidth used to achieve the upgrade.
9194 The @code{non-core} subset refers to the remaining packages. It is
9195 typically useful in cases where an update of the core packages would be
9198 @item --manifest=@var{file}
9199 @itemx -m @var{file}
9200 Select all the packages from the manifest in @var{file}. This is useful to
9201 check if any packages of the user manifest can be updated.
9203 @item --type=@var{updater}
9204 @itemx -t @var{updater}
9205 Select only packages handled by @var{updater} (may be a comma-separated
9206 list of updaters). Currently, @var{updater} may be one of:
9210 the updater for GNU packages;
9212 the updater for GNOME packages;
9214 the updater for KDE packages;
9216 the updater for X.org packages;
9218 the updater for packages hosted on kernel.org;
9220 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9222 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9224 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9226 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9228 the updater for @uref{https://pypi.python.org, PyPI} packages.
9230 the updater for @uref{https://rubygems.org, RubyGems} packages.
9232 the updater for @uref{https://github.com, GitHub} packages.
9234 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9236 the updater for @uref{https://www.stackage.org, Stackage} packages.
9238 the updater for @uref{https://crates.io, Crates} packages.
9240 the updater for @uref{https://launchpad.net, Launchpad} packages.
9243 For instance, the following command only checks for updates of Emacs
9244 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9247 $ guix refresh --type=elpa,cran
9248 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9249 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9254 In addition, @command{guix refresh} can be passed one or more package
9255 names, as in this example:
9258 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9262 The command above specifically updates the @code{emacs} and
9263 @code{idutils} packages. The @code{--select} option would have no
9264 effect in this case.
9266 When considering whether to upgrade a package, it is sometimes
9267 convenient to know which packages would be affected by the upgrade and
9268 should be checked for compatibility. For this the following option may
9269 be used when passing @command{guix refresh} one or more package names:
9273 @item --list-updaters
9275 List available updaters and exit (see @option{--type} above.)
9277 For each updater, display the fraction of packages it covers; at the
9278 end, display the fraction of packages covered by all these updaters.
9280 @item --list-dependent
9282 List top-level dependent packages that would need to be rebuilt as a
9283 result of upgrading one or more packages.
9285 @xref{Invoking guix graph, the @code{reverse-package} type of
9286 @command{guix graph}}, for information on how to visualize the list of
9287 dependents of a package.
9291 Be aware that the @code{--list-dependent} option only
9292 @emph{approximates} the rebuilds that would be required as a result of
9293 an upgrade. More rebuilds might be required under some circumstances.
9296 $ guix refresh --list-dependent flex
9297 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9298 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9301 The command above lists a set of packages that could be built to check
9302 for compatibility with an upgraded @code{flex} package.
9306 @item --list-transitive
9307 List all the packages which one or more packages depend upon.
9310 $ guix refresh --list-transitive flex
9311 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9312 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{}
9317 The command above lists a set of packages which, when changed, would cause
9318 @code{flex} to be rebuilt.
9320 The following options can be used to customize GnuPG operation:
9324 @item --gpg=@var{command}
9325 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9326 for in @code{$PATH}.
9328 @item --keyring=@var{file}
9329 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9330 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9331 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9332 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9333 information on a tool to manipulate keybox files).
9335 When this option is omitted, @command{guix refresh} uses
9336 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9337 signing keys. OpenPGP signatures are checked against keys from this keyring;
9338 missing keys are downloaded to this keyring as well (see
9339 @option{--key-download} below.)
9341 You can export keys from your default GPG keyring into a keybox file using
9342 commands like this one:
9345 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9348 Likewise, you can fetch keys to a specific keybox file like this:
9351 gpg --no-default-keyring --keyring mykeyring.kbx \
9352 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9355 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9356 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9358 @item --key-download=@var{policy}
9359 Handle missing OpenPGP keys according to @var{policy}, which may be one
9364 Always download missing OpenPGP keys from the key server, and add them
9365 to the user's GnuPG keyring.
9368 Never try to download missing OpenPGP keys. Instead just bail out.
9371 When a package signed with an unknown OpenPGP key is encountered, ask
9372 the user whether to download it or not. This is the default behavior.
9375 @item --key-server=@var{host}
9376 Use @var{host} as the OpenPGP key server when importing a public key.
9380 The @code{github} updater uses the
9381 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9382 releases. When used repeatedly e.g.@: when refreshing all packages,
9383 GitHub will eventually refuse to answer any further API requests. By
9384 default 60 API requests per hour are allowed, and a full refresh on all
9385 GitHub packages in Guix requires more than this. Authentication with
9386 GitHub through the use of an API token alleviates these limits. To use
9387 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9388 token procured from @uref{https://github.com/settings/tokens} or
9392 @node Invoking guix lint
9393 @section Invoking @command{guix lint}
9395 @cindex @command{guix lint}
9396 @cindex package, checking for errors
9397 The @command{guix lint} command is meant to help package developers avoid
9398 common errors and use a consistent style. It runs a number of checks on
9399 a given set of packages in order to find common mistakes in their
9400 definitions. Available @dfn{checkers} include (see
9401 @code{--list-checkers} for a complete list):
9406 Validate certain typographical and stylistic rules about package
9407 descriptions and synopses.
9409 @item inputs-should-be-native
9410 Identify inputs that should most likely be native inputs.
9416 @itemx source-file-name
9417 Probe @code{home-page} and @code{source} URLs and report those that are
9418 invalid. Suggest a @code{mirror://} URL when applicable. If the
9419 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9420 URL. Check that the source file name is meaningful, e.g.@: is not just a
9421 version number or ``git-checkout'', without a declared @code{file-name}
9422 (@pxref{origin Reference}).
9424 @item source-unstable-tarball
9425 Parse the @code{source} URL to determine if a tarball from GitHub is
9426 autogenerated or if it is a release tarball. Unfortunately GitHub's
9427 autogenerated tarballs are sometimes regenerated.
9430 @cindex Software Heritage, source code archive
9431 @cindex archival of source code, Software Heritage
9432 Checks whether the package's source code is archived at
9433 @uref{https://www.softwareheritage.org, Software Heritage}.
9435 When the source code that is not archived comes from a version-control system
9436 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
9437 ``save'' request so that it eventually archives it. This ensures that the
9438 source will remain available in the long term, and that Guix can fall back to
9439 Software Heritage should the source code disappear from its original host.
9440 The status of recent ``save'' requests can be
9441 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
9443 When source code is a tarball obtained with @code{url-fetch}, simply print a
9444 message when it is not archived. As of this writing, Software Heritage does
9445 not allow requests to save arbitrary tarballs; we are working on ways to
9446 ensure that non-VCS source code is also archived.
9449 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
9450 request rate per IP address}. When the limit is reached, @command{guix lint}
9451 prints a message and the @code{archival} checker stops doing anything until
9452 that limit has been reset.
9455 @cindex security vulnerabilities
9456 @cindex CVE, Common Vulnerabilities and Exposures
9457 Report known vulnerabilities found in the Common Vulnerabilities and
9458 Exposures (CVE) databases of the current and past year
9459 @uref{https://nvd.nist.gov/download.cfm#CVE_FEED, published by the US
9462 To view information about a particular vulnerability, visit pages such as:
9466 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9468 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9472 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9473 @code{CVE-2015-7554}.
9475 Package developers can specify in package recipes the
9476 @uref{https://nvd.nist.gov/cpe.cfm,Common Platform Enumeration (CPE)}
9477 name and version of the package when they differ from the name or version
9478 that Guix uses, as in this example:
9484 ;; CPE calls this package "grub2".
9485 (properties '((cpe-name . "grub2")
9486 (cpe-version . "2.3"))))
9489 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9490 Some entries in the CVE database do not specify which version of a
9491 package they apply to, and would thus ``stick around'' forever. Package
9492 developers who found CVE alerts and verified they can be ignored can
9493 declare them as in this example:
9499 ;; These CVEs no longer apply and can be safely ignored.
9500 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9503 "CVE-2011-5244")))))
9507 Warn about obvious source code formatting issues: trailing white space,
9508 use of tabulations, etc.
9511 The general syntax is:
9514 guix lint @var{options} @var{package}@dots{}
9517 If no package is given on the command line, then all packages are checked.
9518 The @var{options} may be zero or more of the following:
9521 @item --list-checkers
9523 List and describe all the available checkers that will be run on packages
9528 Only enable the checkers specified in a comma-separated list using the
9529 names returned by @code{--list-checkers}.
9533 @node Invoking guix size
9534 @section Invoking @command{guix size}
9537 @cindex package size
9539 @cindex @command{guix size}
9540 The @command{guix size} command helps package developers profile the
9541 disk usage of packages. It is easy to overlook the impact of an
9542 additional dependency added to a package, or the impact of using a
9543 single output for a package that could easily be split (@pxref{Packages
9544 with Multiple Outputs}). Such are the typical issues that
9545 @command{guix size} can highlight.
9547 The command can be passed one or more package specifications
9548 such as @code{gcc@@4.8}
9549 or @code{guile:debug}, or a file name in the store. Consider this
9553 $ guix size coreutils
9554 store item total self
9555 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9556 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9557 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9558 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9559 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9560 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9561 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9562 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9567 The store items listed here constitute the @dfn{transitive closure} of
9568 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9569 would be returned by:
9572 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9575 Here the output shows three columns next to store items. The first column,
9576 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9577 the store item---that is, its own size plus the size of all its
9578 dependencies. The next column, labeled ``self'', shows the size of the
9579 item itself. The last column shows the ratio of the size of the item
9580 itself to the space occupied by all the items listed here.
9582 In this example, we see that the closure of Coreutils weighs in at
9583 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9584 libraries. (That libc and GCC's libraries represent a large fraction of
9585 the closure is not a problem @i{per se} because they are always available
9586 on the system anyway.)
9588 When the package(s) passed to @command{guix size} are available in the
9589 store@footnote{More precisely, @command{guix size} looks for the
9590 @emph{ungrafted} variant of the given package(s), as returned by
9591 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9592 for information on grafts.}, @command{guix size} queries the daemon to determine its
9593 dependencies, and measures its size in the store, similar to @command{du
9594 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9597 When the given packages are @emph{not} in the store, @command{guix size}
9598 reports information based on the available substitutes
9599 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9600 store items that are not even on disk, only available remotely.
9602 You can also specify several package names:
9605 $ guix size coreutils grep sed bash
9606 store item total self
9607 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9608 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9609 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9610 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9616 In this example we see that the combination of the four packages takes
9617 102.3@tie{}MiB in total, which is much less than the sum of each closure
9618 since they have a lot of dependencies in common.
9620 The available options are:
9624 @item --substitute-urls=@var{urls}
9625 Use substitute information from @var{urls}.
9626 @xref{client-substitute-urls, the same option for @code{guix build}}.
9628 @item --sort=@var{key}
9629 Sort lines according to @var{key}, one of the following options:
9633 the size of each item (the default);
9635 the total size of the item's closure.
9638 @item --map-file=@var{file}
9639 Write a graphical map of disk usage in PNG format to @var{file}.
9641 For the example above, the map looks like this:
9643 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
9644 produced by @command{guix size}}
9646 This option requires that
9647 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
9648 installed and visible in Guile's module search path. When that is not
9649 the case, @command{guix size} fails as it tries to load it.
9651 @item --system=@var{system}
9652 @itemx -s @var{system}
9653 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
9657 @node Invoking guix graph
9658 @section Invoking @command{guix graph}
9661 @cindex @command{guix graph}
9662 @cindex package dependencies
9663 Packages and their dependencies form a @dfn{graph}, specifically a
9664 directed acyclic graph (DAG). It can quickly become difficult to have a
9665 mental model of the package DAG, so the @command{guix graph} command
9666 provides a visual representation of the DAG. By default,
9667 @command{guix graph} emits a DAG representation in the input format of
9668 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
9669 directly to the @command{dot} command of Graphviz. It can also emit an
9670 HTML page with embedded JavaScript code to display a ``chord diagram''
9671 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
9672 emit Cypher queries to construct a graph in a graph database supporting
9673 the @uref{https://www.opencypher.org/, openCypher} query language.
9674 The general syntax is:
9677 guix graph @var{options} @var{package}@dots{}
9680 For example, the following command generates a PDF file representing the
9681 package DAG for the GNU@tie{}Core Utilities, showing its build-time
9685 guix graph coreutils | dot -Tpdf > dag.pdf
9688 The output looks like this:
9690 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
9692 Nice little graph, no?
9694 But there is more than one graph! The one above is concise: it is the
9695 graph of package objects, omitting implicit inputs such as GCC, libc,
9696 grep, etc. It is often useful to have such a concise graph, but
9697 sometimes one may want to see more details. @command{guix graph} supports
9698 several types of graphs, allowing you to choose the level of detail:
9702 This is the default type used in the example above. It shows the DAG of
9703 package objects, excluding implicit dependencies. It is concise, but
9704 filters out many details.
9706 @item reverse-package
9707 This shows the @emph{reverse} DAG of packages. For example:
9710 guix graph --type=reverse-package ocaml
9713 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
9714 you are also interested in cases where OCaml is an implicit dependency, see
9715 @code{reverse-bag} below.)
9717 Note that for core packages this can yield huge graphs. If all you want
9718 is to know the number of packages that depend on a given package, use
9719 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
9720 @option{--list-dependent}}).
9723 This is the package DAG, @emph{including} implicit inputs.
9725 For instance, the following command:
9728 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
9731 ...@: yields this bigger graph:
9733 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
9735 At the bottom of the graph, we see all the implicit inputs of
9736 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
9738 Now, note that the dependencies of these implicit inputs---that is, the
9739 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
9740 here, for conciseness.
9743 Similar to @code{bag-emerged}, but this time including all the bootstrap
9746 @item bag-with-origins
9747 Similar to @code{bag}, but also showing origins and their dependencies.
9750 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
9751 it also takes implicit dependencies into account. For example:
9754 guix graph -t reverse-bag dune
9758 ...@: yields the graph of all packages that depend on Dune, directly or
9759 indirectly. Since Dune is an @emph{implicit} dependency of many packages
9760 @i{via} @code{dune-build-system}, this shows a large number of packages,
9761 whereas @code{reverse-package} would show very few if any.
9764 This is the most detailed representation: It shows the DAG of
9765 derivations (@pxref{Derivations}) and plain store items. Compared to
9766 the above representation, many additional nodes are visible, including
9767 build scripts, patches, Guile modules, etc.
9769 For this type of graph, it is also possible to pass a @file{.drv} file
9770 name instead of a package name, as in:
9773 guix graph -t derivation `guix system build -d my-config.scm`
9777 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
9778 For example, the following command shows the graph for the package
9779 module that defines the @code{guile} package:
9782 guix graph -t module guile | dot -Tpdf > module-graph.pdf
9786 All the types above correspond to @emph{build-time dependencies}. The
9787 following graph type represents the @emph{run-time dependencies}:
9791 This is the graph of @dfn{references} of a package output, as returned
9792 by @command{guix gc --references} (@pxref{Invoking guix gc}).
9794 If the given package output is not available in the store, @command{guix
9795 graph} attempts to obtain dependency information from substitutes.
9797 Here you can also pass a store file name instead of a package name. For
9798 example, the command below produces the reference graph of your profile
9799 (which can be big!):
9802 guix graph -t references `readlink -f ~/.guix-profile`
9806 This is the graph of the @dfn{referrers} of a store item, as returned by
9807 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
9809 This relies exclusively on local information from your store. For
9810 instance, let us suppose that the current Inkscape is available in 10
9811 profiles on your machine; @command{guix graph -t referrers inkscape}
9812 will show a graph rooted at Inkscape and with those 10 profiles linked
9815 It can help determine what is preventing a store item from being garbage
9820 The available options are the following:
9823 @item --type=@var{type}
9824 @itemx -t @var{type}
9825 Produce a graph output of @var{type}, where @var{type} must be one of
9826 the values listed above.
9829 List the supported graph types.
9831 @item --backend=@var{backend}
9832 @itemx -b @var{backend}
9833 Produce a graph using the selected @var{backend}.
9835 @item --list-backends
9836 List the supported graph backends.
9838 Currently, the available backends are Graphviz and d3.js.
9840 @item --expression=@var{expr}
9841 @itemx -e @var{expr}
9842 Consider the package @var{expr} evaluates to.
9844 This is useful to precisely refer to a package, as in this example:
9847 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
9850 @item --system=@var{system}
9851 @itemx -s @var{system}
9852 Display the graph for @var{system}---e.g., @code{i686-linux}.
9854 The package dependency graph is largely architecture-independent, but there
9855 are some architecture-dependent bits that this option allows you to visualize.
9860 @node Invoking guix publish
9861 @section Invoking @command{guix publish}
9863 @cindex @command{guix publish}
9864 The purpose of @command{guix publish} is to enable users to easily share
9865 their store with others, who can then use it as a substitute server
9866 (@pxref{Substitutes}).
9868 When @command{guix publish} runs, it spawns an HTTP server which allows
9869 anyone with network access to obtain substitutes from it. This means
9870 that any machine running Guix can also act as if it were a build farm,
9871 since the HTTP interface is compatible with Cuirass, the software behind
9872 the @code{@value{SUBSTITUTE-SERVER}} build farm.
9874 For security, each substitute is signed, allowing recipients to check
9875 their authenticity and integrity (@pxref{Substitutes}). Because
9876 @command{guix publish} uses the signing key of the system, which is only
9877 readable by the system administrator, it must be started as root; the
9878 @code{--user} option makes it drop root privileges early on.
9880 The signing key pair must be generated before @command{guix publish} is
9881 launched, using @command{guix archive --generate-key} (@pxref{Invoking
9884 The general syntax is:
9887 guix publish @var{options}@dots{}
9890 Running @command{guix publish} without any additional arguments will
9891 spawn an HTTP server on port 8080:
9897 Once a publishing server has been authorized (@pxref{Invoking guix
9898 archive}), the daemon may download substitutes from it:
9901 guix-daemon --substitute-urls=http://example.org:8080
9904 By default, @command{guix publish} compresses archives on the fly as it
9905 serves them. This ``on-the-fly'' mode is convenient in that it requires
9906 no setup and is immediately available. However, when serving lots of
9907 clients, we recommend using the @option{--cache} option, which enables
9908 caching of the archives before they are sent to clients---see below for
9909 details. The @command{guix weather} command provides a handy way to
9910 check what a server provides (@pxref{Invoking guix weather}).
9912 As a bonus, @command{guix publish} also serves as a content-addressed
9913 mirror for source files referenced in @code{origin} records
9914 (@pxref{origin Reference}). For instance, assuming @command{guix
9915 publish} is running on @code{example.org}, the following URL returns the
9916 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
9917 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
9920 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
9923 Obviously, these URLs only work for files that are in the store; in
9924 other cases, they return 404 (``Not Found'').
9926 @cindex build logs, publication
9927 Build logs are available from @code{/log} URLs like:
9930 http://example.org/log/gwspk@dots{}-guile-2.2.3
9934 When @command{guix-daemon} is configured to save compressed build logs,
9935 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
9936 URLs return the compressed log as-is, with an appropriate
9937 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
9938 running @command{guix-daemon} with @code{--log-compression=gzip} since
9939 Web browsers can automatically decompress it, which is not the case with
9942 The following options are available:
9945 @item --port=@var{port}
9946 @itemx -p @var{port}
9947 Listen for HTTP requests on @var{port}.
9949 @item --listen=@var{host}
9950 Listen on the network interface for @var{host}. The default is to
9951 accept connections from any interface.
9953 @item --user=@var{user}
9954 @itemx -u @var{user}
9955 Change privileges to @var{user} as soon as possible---i.e., once the
9956 server socket is open and the signing key has been read.
9958 @item --compression[=@var{method}[:@var{level}]]
9959 @itemx -C [@var{method}[:@var{level}]]
9960 Compress data using the given @var{method} and @var{level}. @var{method} is
9961 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
9964 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
9965 to different compression levels: 1 is the fastest, and 9 is the best
9966 (CPU-intensive). The default is 3.
9968 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
9969 increase in CPU usage; see
9970 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
9973 Unless @option{--cache} is used, compression occurs on the fly and
9974 the compressed streams are not
9975 cached. Thus, to reduce load on the machine that runs @command{guix
9976 publish}, it may be a good idea to choose a low compression level, to
9977 run @command{guix publish} behind a caching proxy, or to use
9978 @option{--cache}. Using @option{--cache} has the advantage that it
9979 allows @command{guix publish} to add @code{Content-Length} HTTP header
9982 This option can be repeated, in which case every substitute gets compressed
9983 using all the selected methods, and all of them are advertised. This is
9984 useful when users may not support all the compression methods: they can select
9985 the one they support.
9987 @item --cache=@var{directory}
9988 @itemx -c @var{directory}
9989 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
9990 and only serve archives that are in cache.
9992 When this option is omitted, archives and meta-data are created
9993 on-the-fly. This can reduce the available bandwidth, especially when
9994 compression is enabled, since this may become CPU-bound. Another
9995 drawback of the default mode is that the length of archives is not known
9996 in advance, so @command{guix publish} does not add a
9997 @code{Content-Length} HTTP header to its responses, which in turn
9998 prevents clients from knowing the amount of data being downloaded.
10000 Conversely, when @option{--cache} is used, the first request for a store
10001 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10002 background process to @dfn{bake} the archive---computing its
10003 @code{.narinfo} and compressing the archive, if needed. Once the
10004 archive is cached in @var{directory}, subsequent requests succeed and
10005 are served directly from the cache, which guarantees that clients get
10006 the best possible bandwidth.
10008 The ``baking'' process is performed by worker threads. By default, one
10009 thread per CPU core is created, but this can be customized. See
10010 @option{--workers} below.
10012 When @option{--ttl} is used, cached entries are automatically deleted
10013 when they have expired.
10015 @item --workers=@var{N}
10016 When @option{--cache} is used, request the allocation of @var{N} worker
10017 threads to ``bake'' archives.
10019 @item --ttl=@var{ttl}
10020 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10021 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10022 days, @code{1m} means 1 month, and so on.
10024 This allows the user's Guix to keep substitute information in cache for
10025 @var{ttl}. However, note that @code{guix publish} does not itself
10026 guarantee that the store items it provides will indeed remain available
10027 for as long as @var{ttl}.
10029 Additionally, when @option{--cache} is used, cached entries that have
10030 not been accessed for @var{ttl} and that no longer have a corresponding
10031 item in the store, may be deleted.
10033 @item --nar-path=@var{path}
10034 Use @var{path} as the prefix for the URLs of ``nar'' files
10035 (@pxref{Invoking guix archive, normalized archives}).
10037 By default, nars are served at a URL such as
10038 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
10039 change the @code{/nar} part to @var{path}.
10041 @item --public-key=@var{file}
10042 @itemx --private-key=@var{file}
10043 Use the specific @var{file}s as the public/private key pair used to sign
10044 the store items being published.
10046 The files must correspond to the same key pair (the private key is used
10047 for signing and the public key is merely advertised in the signature
10048 metadata). They must contain keys in the canonical s-expression format
10049 as produced by @command{guix archive --generate-key} (@pxref{Invoking
10050 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
10051 @file{/etc/guix/signing-key.sec} are used.
10053 @item --repl[=@var{port}]
10054 @itemx -r [@var{port}]
10055 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
10056 Reference Manual}) on @var{port} (37146 by default). This is used
10057 primarily for debugging a running @command{guix publish} server.
10060 Enabling @command{guix publish} on Guix System is a one-liner: just
10061 instantiate a @code{guix-publish-service-type} service in the @code{services} field
10062 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
10063 @code{guix-publish-service-type}}).
10065 If you are instead running Guix on a ``foreign distro'', follow these
10070 If your host distro uses the systemd init system:
10073 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
10074 /etc/systemd/system/
10075 # systemctl start guix-publish && systemctl enable guix-publish
10079 If your host distro uses the Upstart init system:
10082 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
10083 # start guix-publish
10087 Otherwise, proceed similarly with your distro's init system.
10090 @node Invoking guix challenge
10091 @section Invoking @command{guix challenge}
10093 @cindex reproducible builds
10094 @cindex verifiable builds
10095 @cindex @command{guix challenge}
10097 Do the binaries provided by this server really correspond to the source
10098 code it claims to build? Is a package build process deterministic?
10099 These are the questions the @command{guix challenge} command attempts to
10102 The former is obviously an important question: Before using a substitute
10103 server (@pxref{Substitutes}), one had better @emph{verify} that it
10104 provides the right binaries, and thus @emph{challenge} it. The latter
10105 is what enables the former: If package builds are deterministic, then
10106 independent builds of the package should yield the exact same result,
10107 bit for bit; if a server provides a binary different from the one
10108 obtained locally, it may be either corrupt or malicious.
10110 We know that the hash that shows up in @file{/gnu/store} file names is
10111 the hash of all the inputs of the process that built the file or
10112 directory---compilers, libraries, build scripts,
10113 etc. (@pxref{Introduction}). Assuming deterministic build processes,
10114 one store file name should map to exactly one build output.
10115 @command{guix challenge} checks whether there is, indeed, a single
10116 mapping by comparing the build outputs of several independent builds of
10117 any given store item.
10119 The command output looks like this:
10122 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10123 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
10124 updating list of substitutes from 'https://guix.example.org'... 100.0%
10125 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
10126 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10127 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10128 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
10129 /gnu/store/@dots{}-git-2.5.0 contents differ:
10130 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
10131 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
10132 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
10133 /gnu/store/@dots{}-pius-2.1.1 contents differ:
10134 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10135 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10136 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
10140 6,406 store items were analyzed:
10141 - 4,749 (74.1%) were identical
10142 - 525 (8.2%) differed
10143 - 1,132 (17.7%) were inconclusive
10147 In this example, @command{guix challenge} first scans the store to
10148 determine the set of locally-built derivations---as opposed to store
10149 items that were downloaded from a substitute server---and then queries
10150 all the substitute servers. It then reports those store items for which
10151 the servers obtained a result different from the local build.
10153 @cindex non-determinism, in package builds
10154 As an example, @code{guix.example.org} always gets a different answer.
10155 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10156 case of Git. This might indicate that the build process of Git is
10157 non-deterministic, meaning that its output varies as a function of
10158 various things that Guix does not fully control, in spite of building
10159 packages in isolated environments (@pxref{Features}). Most common
10160 sources of non-determinism include the addition of timestamps in build
10161 results, the inclusion of random numbers, and directory listings sorted
10162 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
10165 To find out what is wrong with this Git binary, we can do something along
10166 these lines (@pxref{Invoking guix archive}):
10169 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0 \
10170 | guix archive -x /tmp/git
10171 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
10174 This command shows the difference between the files resulting from the
10175 local build, and the files resulting from the build on
10176 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
10177 diffutils, Comparing and Merging Files}). The @command{diff} command
10178 works great for text files. When binary files differ, a better option
10179 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
10180 visualize differences for all kinds of files.
10182 Once you have done that work, you can tell whether the differences are due
10183 to a non-deterministic build process or to a malicious server. We try
10184 hard to remove sources of non-determinism in packages to make it easier
10185 to verify substitutes, but of course, this is a process that
10186 involves not just Guix, but a large part of the free software community.
10187 In the meantime, @command{guix challenge} is one tool to help address
10190 If you are writing packages for Guix, you are encouraged to check
10191 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
10192 same build result as you did with:
10195 $ guix challenge @var{package}
10199 where @var{package} is a package specification such as
10200 @code{guile@@2.0} or @code{glibc:debug}.
10202 The general syntax is:
10205 guix challenge @var{options} [@var{packages}@dots{}]
10208 When a difference is found between the hash of a locally-built item and
10209 that of a server-provided substitute, or among substitutes provided by
10210 different servers, the command displays it as in the example above and
10211 its exit code is 2 (other non-zero exit codes denote other kinds of
10214 The one option that matters is:
10218 @item --substitute-urls=@var{urls}
10219 Consider @var{urls} the whitespace-separated list of substitute source
10220 URLs to compare to.
10224 Show details about matches (identical contents) in addition to
10225 information about mismatches.
10229 @node Invoking guix copy
10230 @section Invoking @command{guix copy}
10232 @cindex copy, of store items, over SSH
10233 @cindex SSH, copy of store items
10234 @cindex sharing store items across machines
10235 @cindex transferring store items across machines
10236 The @command{guix copy} command copies items from the store of one
10237 machine to that of another machine over a secure shell (SSH)
10238 connection@footnote{This command is available only when Guile-SSH was
10239 found. @xref{Requirements}, for details.}. For example, the following
10240 command copies the @code{coreutils} package, the user's profile, and all
10241 their dependencies over to @var{host}, logged in as @var{user}:
10244 guix copy --to=@var{user}@@@var{host} \
10245 coreutils `readlink -f ~/.guix-profile`
10248 If some of the items to be copied are already present on @var{host},
10249 they are not actually sent.
10251 The command below retrieves @code{libreoffice} and @code{gimp} from
10252 @var{host}, assuming they are available there:
10255 guix copy --from=@var{host} libreoffice gimp
10258 The SSH connection is established using the Guile-SSH client, which is
10259 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10260 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10262 The key used to sign items that are sent must be accepted by the remote
10263 machine. Likewise, the key used by the remote machine to sign items you
10264 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10265 own daemon. @xref{Invoking guix archive}, for more information about
10266 store item authentication.
10268 The general syntax is:
10271 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10274 You must always specify one of the following options:
10277 @item --to=@var{spec}
10278 @itemx --from=@var{spec}
10279 Specify the host to send to or receive from. @var{spec} must be an SSH
10280 spec such as @code{example.org}, @code{charlie@@example.org}, or
10281 @code{charlie@@example.org:2222}.
10284 The @var{items} can be either package names, such as @code{gimp}, or
10285 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10287 When specifying the name of a package to send, it is first built if
10288 needed, unless @option{--dry-run} was specified. Common build options
10289 are supported (@pxref{Common Build Options}).
10292 @node Invoking guix container
10293 @section Invoking @command{guix container}
10295 @cindex @command{guix container}
10297 As of version @value{VERSION}, this tool is experimental. The interface
10298 is subject to radical change in the future.
10301 The purpose of @command{guix container} is to manipulate processes
10302 running within an isolated environment, commonly known as a
10303 ``container'', typically created by the @command{guix environment}
10304 (@pxref{Invoking guix environment}) and @command{guix system container}
10305 (@pxref{Invoking guix system}) commands.
10307 The general syntax is:
10310 guix container @var{action} @var{options}@dots{}
10313 @var{action} specifies the operation to perform with a container, and
10314 @var{options} specifies the context-specific arguments for the action.
10316 The following actions are available:
10320 Execute a command within the context of a running container.
10325 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10328 @var{pid} specifies the process ID of the running container.
10329 @var{program} specifies an executable file name within the root file
10330 system of the container. @var{arguments} are the additional options that
10331 will be passed to @var{program}.
10333 The following command launches an interactive login shell inside a
10334 Guix system container, started by @command{guix system container}, and whose
10335 process ID is 9001:
10338 guix container exec 9001 /run/current-system/profile/bin/bash --login
10341 Note that the @var{pid} cannot be the parent process of a container. It
10342 must be PID 1 of the container or one of its child processes.
10346 @node Invoking guix weather
10347 @section Invoking @command{guix weather}
10349 Occasionally you're grumpy because substitutes are lacking and you end
10350 up building packages by yourself (@pxref{Substitutes}). The
10351 @command{guix weather} command reports on substitute availability on the
10352 specified servers so you can have an idea of whether you'll be grumpy
10353 today. It can sometimes be useful info as a user, but it is primarily
10354 useful to people running @command{guix publish} (@pxref{Invoking guix
10357 @cindex statistics, for substitutes
10358 @cindex availability of substitutes
10359 @cindex substitute availability
10360 @cindex weather, substitute availability
10361 Here's a sample run:
10364 $ guix weather --substitute-urls=https://guix.example.org
10365 computing 5,872 package derivations for x86_64-linux...
10366 looking for 6,128 store items on https://guix.example.org..
10367 updating list of substitutes from 'https://guix.example.org'... 100.0%
10368 https://guix.example.org
10369 43.4% substitutes available (2,658 out of 6,128)
10370 7,032.5 MiB of nars (compressed)
10371 19,824.2 MiB on disk (uncompressed)
10372 0.030 seconds per request (182.9 seconds in total)
10373 33.5 requests per second
10375 9.8% (342 out of 3,470) of the missing items are queued
10377 x86_64-linux: 518 (59.7%)
10378 i686-linux: 221 (25.5%)
10379 aarch64-linux: 128 (14.8%)
10380 build rate: 23.41 builds per hour
10381 x86_64-linux: 11.16 builds per hour
10382 i686-linux: 6.03 builds per hour
10383 aarch64-linux: 6.41 builds per hour
10386 @cindex continuous integration, statistics
10387 As you can see, it reports the fraction of all the packages for which
10388 substitutes are available on the server---regardless of whether
10389 substitutes are enabled, and regardless of whether this server's signing
10390 key is authorized. It also reports the size of the compressed archives
10391 (``nars'') provided by the server, the size the corresponding store
10392 items occupy in the store (assuming deduplication is turned off), and
10393 the server's throughput. The second part gives continuous integration
10394 (CI) statistics, if the server supports it. In addition, using the
10395 @option{--coverage} option, @command{guix weather} can list ``important''
10396 package substitutes missing on the server (see below).
10398 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10399 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10400 challenge}, it ignores signatures on those substitutes, which is
10401 innocuous since the command only gathers statistics and cannot install
10404 The general syntax is:
10407 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10410 When @var{packages} is omitted, @command{guix weather} checks the availability
10411 of substitutes for @emph{all} the packages, or for those specified with
10412 @option{--manifest}; otherwise it only considers the specified packages. It
10413 is also possible to query specific system types with @option{--system}. The
10414 available options are listed below.
10417 @item --substitute-urls=@var{urls}
10418 @var{urls} is the space-separated list of substitute server URLs to
10419 query. When this option is omitted, the default set of substitute
10420 servers is queried.
10422 @item --system=@var{system}
10423 @itemx -s @var{system}
10424 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10425 option can be repeated, in which case @command{guix weather} will query
10426 substitutes for several system types.
10428 @item --manifest=@var{file}
10429 Instead of querying substitutes for all the packages, only ask for those
10430 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10431 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10434 @item --coverage[=@var{count}]
10435 @itemx -c [@var{count}]
10436 Report on substitute coverage for packages: list packages with at least
10437 @var{count} dependents (zero by default) for which substitutes are
10438 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10439 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10440 @var{b} usually lacks substitutes as well. The result looks like this:
10443 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10444 computing 8,983 package derivations for x86_64-linux...
10445 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10446 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10447 @value{SUBSTITUTE-URL}
10448 64.7% substitutes available (6,047 out of 9,343)
10450 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10451 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10452 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10453 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10457 What this example shows is that @code{kcoreaddons} and presumably the 58
10458 packages that depend on it have no substitutes at @code{ci.guix.info};
10459 likewise for @code{qgpgme} and the 46 packages that depend on it.
10461 If you are a Guix developer, or if you are taking care of this build farm,
10462 you'll probably want to have a closer look at these packages: they may simply
10466 @node Invoking guix processes
10467 @section Invoking @command{guix processes}
10469 The @command{guix processes} command can be useful to developers and system
10470 administrators, especially on multi-user machines and on build farms: it lists
10471 the current sessions (connections to the daemon), as well as information about
10472 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10473 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10474 listed.}. Here's an example of the information it returns:
10477 $ sudo guix processes
10480 ClientCommand: guix environment --ad-hoc python
10484 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10488 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10489 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10490 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10491 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10492 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10493 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10494 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10497 In this example we see that @command{guix-daemon} has three clients:
10498 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10499 integration tool; their process identifier (PID) is given by the
10500 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10501 @command{guix-daemon} sub-process of this particular session.
10503 The @code{LockHeld} fields show which store items are currently locked by this
10504 session, which corresponds to store items being built or substituted (the
10505 @code{LockHeld} field is not displayed when @command{guix processes} is not
10506 running as root.) Last, by looking at the @code{ChildProcess} field, we
10507 understand that these three builds are being offloaded (@pxref{Daemon Offload
10510 The output is in Recutils format so we can use the handy @command{recsel}
10511 command to select sessions of interest (@pxref{Selection Expressions,,,
10512 recutils, GNU recutils manual}). As an example, the command shows the command
10513 line and PID of the client that triggered the build of a Perl package:
10516 $ sudo guix processes | \
10517 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10519 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10523 @node System Configuration
10524 @chapter System Configuration
10526 @cindex system configuration
10527 Guix System supports a consistent whole-system configuration
10528 mechanism. By that we mean that all aspects of the global system
10529 configuration---such as the available system services, timezone and
10530 locale settings, user accounts---are declared in a single place. Such
10531 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10533 One of the advantages of putting all the system configuration under the
10534 control of Guix is that it supports transactional system upgrades, and
10535 makes it possible to roll back to a previous system instantiation,
10536 should something go wrong with the new one (@pxref{Features}). Another
10537 advantage is that it makes it easy to replicate the exact same configuration
10538 across different machines, or at different points in time, without
10539 having to resort to additional administration tools layered on top of
10540 the own tools of the system.
10541 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10543 This section describes this mechanism. First we focus on the system
10544 administrator's viewpoint---explaining how the system is configured and
10545 instantiated. Then we show how this mechanism can be extended, for
10546 instance to support new system services.
10549 * Using the Configuration System:: Customizing your GNU system.
10550 * operating-system Reference:: Detail of operating-system declarations.
10551 * File Systems:: Configuring file system mounts.
10552 * Mapped Devices:: Block device extra processing.
10553 * User Accounts:: Specifying user accounts.
10554 * Keyboard Layout:: How the system interprets key strokes.
10555 * Locales:: Language and cultural convention settings.
10556 * Services:: Specifying system services.
10557 * Setuid Programs:: Programs running with root privileges.
10558 * X.509 Certificates:: Authenticating HTTPS servers.
10559 * Name Service Switch:: Configuring libc's name service switch.
10560 * Initial RAM Disk:: Linux-Libre bootstrapping.
10561 * Bootloader Configuration:: Configuring the boot loader.
10562 * Invoking guix system:: Instantiating a system configuration.
10563 * Invoking guix deploy:: Deploying a system configuration to a remote host.
10564 * Running Guix in a VM:: How to run Guix System in a virtual machine.
10565 * Defining Services:: Adding new service definitions.
10568 @node Using the Configuration System
10569 @section Using the Configuration System
10571 The operating system is configured by providing an
10572 @code{operating-system} declaration in a file that can then be passed to
10573 the @command{guix system} command (@pxref{Invoking guix system}). A
10574 simple setup, with the default system services, the default Linux-Libre
10575 kernel, initial RAM disk, and boot loader looks like this:
10577 @findex operating-system
10579 @include os-config-bare-bones.texi
10582 This example should be self-describing. Some of the fields defined
10583 above, such as @code{host-name} and @code{bootloader}, are mandatory.
10584 Others, such as @code{packages} and @code{services}, can be omitted, in
10585 which case they get a default value.
10587 Below we discuss the effect of some of the most important fields
10588 (@pxref{operating-system Reference}, for details about all the available
10589 fields), and how to @dfn{instantiate} the operating system using
10590 @command{guix system}.
10592 @unnumberedsubsec Bootloader
10594 @cindex legacy boot, on Intel machines
10595 @cindex BIOS boot, on Intel machines
10598 The @code{bootloader} field describes the method that will be used to boot
10599 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
10600 mode, as in the example above. However, more recent machines rely instead on
10601 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
10602 the @code{bootloader} field should contain something along these lines:
10605 (bootloader-configuration
10606 (bootloader grub-efi-bootloader)
10607 (target "/boot/efi"))
10610 @xref{Bootloader Configuration}, for more information on the available
10611 configuration options.
10613 @unnumberedsubsec Globally-Visible Packages
10615 @vindex %base-packages
10616 The @code{packages} field lists packages that will be globally visible
10617 on the system, for all user accounts---i.e., in every user's @code{PATH}
10618 environment variable---in addition to the per-user profiles
10619 (@pxref{Invoking guix package}). The @code{%base-packages} variable
10620 provides all the tools one would expect for basic user and administrator
10621 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
10622 the GNU Zile lightweight text editor, @command{find}, @command{grep},
10623 etc. The example above adds GNU@tie{}Screen to those,
10624 taken from the @code{(gnu packages screen)}
10625 module (@pxref{Package Modules}). The
10626 @code{(list package output)} syntax can be used to add a specific output
10630 (use-modules (gnu packages))
10631 (use-modules (gnu packages dns))
10635 (packages (cons (list bind "utils")
10639 @findex specification->package
10640 Referring to packages by variable name, like @code{bind} above, has
10641 the advantage of being unambiguous; it also allows typos and such to be
10642 diagnosed right away as ``unbound variables''. The downside is that one
10643 needs to know which module defines which package, and to augment the
10644 @code{use-package-modules} line accordingly. To avoid that, one can use
10645 the @code{specification->package} procedure of the @code{(gnu packages)}
10646 module, which returns the best package for a given name or name and
10650 (use-modules (gnu packages))
10654 (packages (append (map specification->package
10655 '("tcpdump" "htop" "gnupg@@2.0"))
10659 @unnumberedsubsec System Services
10662 @vindex %base-services
10663 The @code{services} field lists @dfn{system services} to be made
10664 available when the system starts (@pxref{Services}).
10665 The @code{operating-system} declaration above specifies that, in
10666 addition to the basic services, we want the OpenSSH secure shell
10667 daemon listening on port 2222 (@pxref{Networking Services,
10668 @code{openssh-service-type}}). Under the hood,
10669 @code{openssh-service-type} arranges so that @command{sshd} is started with the
10670 right command-line options, possibly with supporting configuration files
10671 generated as needed (@pxref{Defining Services}).
10673 @cindex customization, of services
10674 @findex modify-services
10675 Occasionally, instead of using the base services as is, you will want to
10676 customize them. To do this, use @code{modify-services} (@pxref{Service
10677 Reference, @code{modify-services}}) to modify the list.
10679 For example, suppose you want to modify @code{guix-daemon} and Mingetty
10680 (the console log-in) in the @code{%base-services} list (@pxref{Base
10681 Services, @code{%base-services}}). To do that, you can write the
10682 following in your operating system declaration:
10685 (define %my-services
10686 ;; My very own list of services.
10687 (modify-services %base-services
10688 (guix-service-type config =>
10689 (guix-configuration
10691 (use-substitutes? #f)
10692 (extra-options '("--gc-keep-derivations"))))
10693 (mingetty-service-type config =>
10694 (mingetty-configuration
10695 (inherit config)))))
10699 (services %my-services))
10702 This changes the configuration---i.e., the service parameters---of the
10703 @code{guix-service-type} instance, and that of all the
10704 @code{mingetty-service-type} instances in the @code{%base-services} list.
10705 Observe how this is accomplished: first, we arrange for the original
10706 configuration to be bound to the identifier @code{config} in the
10707 @var{body}, and then we write the @var{body} so that it evaluates to the
10708 desired configuration. In particular, notice how we use @code{inherit}
10709 to create a new configuration which has the same values as the old
10710 configuration, but with a few modifications.
10712 @cindex encrypted disk
10713 The configuration for a typical ``desktop'' usage, with an encrypted
10714 root partition, the X11 display
10715 server, GNOME and Xfce (users can choose which of these desktop
10716 environments to use at the log-in screen by pressing @kbd{F1}), network
10717 management, power management, and more, would look like this:
10720 @include os-config-desktop.texi
10723 A graphical system with a choice of lightweight window managers
10724 instead of full-blown desktop environments would look like this:
10727 @include os-config-lightweight-desktop.texi
10730 This example refers to the @file{/boot/efi} file system by its UUID,
10731 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
10732 as returned by the @command{blkid} command.
10734 @xref{Desktop Services}, for the exact list of services provided by
10735 @code{%desktop-services}. @xref{X.509 Certificates}, for background
10736 information about the @code{nss-certs} package that is used here.
10738 Again, @code{%desktop-services} is just a list of service objects. If
10739 you want to remove services from there, you can do so using the
10740 procedures for list filtering (@pxref{SRFI-1 Filtering and
10741 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
10742 following expression returns a list that contains all the services in
10743 @code{%desktop-services} minus the Avahi service:
10746 (remove (lambda (service)
10747 (eq? (service-kind service) avahi-service-type))
10751 @unnumberedsubsec Instantiating the System
10753 Assuming the @code{operating-system} declaration
10754 is stored in the @file{my-system-config.scm}
10755 file, the @command{guix system reconfigure my-system-config.scm} command
10756 instantiates that configuration, and makes it the default GRUB boot
10757 entry (@pxref{Invoking guix system}).
10759 The normal way to change the system configuration is by updating this
10760 file and re-running @command{guix system reconfigure}. One should never
10761 have to touch files in @file{/etc} or to run commands that modify the
10762 system state such as @command{useradd} or @command{grub-install}. In
10763 fact, you must avoid that since that would not only void your warranty
10764 but also prevent you from rolling back to previous versions of your
10765 system, should you ever need to.
10767 @cindex roll-back, of the operating system
10768 Speaking of roll-back, each time you run @command{guix system
10769 reconfigure}, a new @dfn{generation} of the system is created---without
10770 modifying or deleting previous generations. Old system generations get
10771 an entry in the bootloader boot menu, allowing you to boot them in case
10772 something went wrong with the latest generation. Reassuring, no? The
10773 @command{guix system list-generations} command lists the system
10774 generations available on disk. It is also possible to roll back the
10775 system via the commands @command{guix system roll-back} and
10776 @command{guix system switch-generation}.
10778 Although the @command{guix system reconfigure} command will not modify
10779 previous generations, you must take care when the current generation is not
10780 the latest (e.g., after invoking @command{guix system roll-back}), since
10781 the operation might overwrite a later generation (@pxref{Invoking guix
10784 @unnumberedsubsec The Programming Interface
10786 At the Scheme level, the bulk of an @code{operating-system} declaration
10787 is instantiated with the following monadic procedure (@pxref{The Store
10790 @deffn {Monadic Procedure} operating-system-derivation os
10791 Return a derivation that builds @var{os}, an @code{operating-system}
10792 object (@pxref{Derivations}).
10794 The output of the derivation is a single directory that refers to all
10795 the packages, configuration files, and other supporting files needed to
10796 instantiate @var{os}.
10799 This procedure is provided by the @code{(gnu system)} module. Along
10800 with @code{(gnu services)} (@pxref{Services}), this module contains the
10801 guts of Guix System. Make sure to visit it!
10804 @node operating-system Reference
10805 @section @code{operating-system} Reference
10807 This section summarizes all the options available in
10808 @code{operating-system} declarations (@pxref{Using the Configuration
10811 @deftp {Data Type} operating-system
10812 This is the data type representing an operating system configuration.
10813 By that, we mean all the global system configuration, not per-user
10814 configuration (@pxref{Using the Configuration System}).
10817 @item @code{kernel} (default: @var{linux-libre})
10818 The package object of the operating system kernel to use@footnote{Currently
10819 only the Linux-libre kernel is supported. In the future, it will be
10820 possible to use the GNU@tie{}Hurd.}.
10822 @item @code{kernel-arguments} (default: @code{'("quiet")})
10823 List of strings or gexps representing additional arguments to pass on
10824 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
10826 @item @code{bootloader}
10827 The system bootloader configuration object. @xref{Bootloader Configuration}.
10830 This is the label (a string) as it appears in the bootloader's menu entry.
10831 The default label includes the kernel name and version.
10833 @item @code{keyboard-layout} (default: @code{#f})
10834 This field specifies the keyboard layout to use in the console. It can be
10835 either @code{#f}, in which case the default keyboard layout is used (usually
10836 US English), or a @code{<keyboard-layout>} record.
10838 This keyboard layout is in effect as soon as the kernel has booted. For
10839 instance, it is the keyboard layout in effect when you type a passphrase if
10840 your root file system is on a @code{luks-device-mapping} mapped device
10841 (@pxref{Mapped Devices}).
10844 This does @emph{not} specify the keyboard layout used by the bootloader, nor
10845 that used by the graphical display server. @xref{Bootloader Configuration},
10846 for information on how to specify the bootloader's keyboard layout. @xref{X
10847 Window}, for information on how to specify the keyboard layout used by the X
10851 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
10853 @cindex initial RAM disk
10854 The list of Linux kernel modules that need to be available in the
10855 initial RAM disk. @xref{Initial RAM Disk}.
10857 @item @code{initrd} (default: @code{base-initrd})
10858 A procedure that returns an initial RAM disk for the Linux
10859 kernel. This field is provided to support low-level customization and
10860 should rarely be needed for casual use. @xref{Initial RAM Disk}.
10862 @item @code{firmware} (default: @code{%base-firmware})
10864 List of firmware packages loadable by the operating system kernel.
10866 The default includes firmware needed for Atheros- and Broadcom-based
10867 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
10868 respectively). @xref{Hardware Considerations}, for more info on
10869 supported hardware.
10871 @item @code{host-name}
10874 @item @code{hosts-file}
10876 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
10877 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
10878 Reference Manual}). The default is a file with entries for
10879 @code{localhost} and @var{host-name}.
10881 @item @code{mapped-devices} (default: @code{'()})
10882 A list of mapped devices. @xref{Mapped Devices}.
10884 @item @code{file-systems}
10885 A list of file systems. @xref{File Systems}.
10887 @item @code{swap-devices} (default: @code{'()})
10888 @cindex swap devices
10889 A list of strings identifying devices or files to be used for ``swap
10890 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
10891 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
10892 It is possible to specify a swap file in a file system on a mapped
10893 device, provided that the necessary device mapping and file system are
10894 also specified. @xref{Mapped Devices} and @ref{File Systems}.
10896 @item @code{users} (default: @code{%base-user-accounts})
10897 @itemx @code{groups} (default: @code{%base-groups})
10898 List of user accounts and groups. @xref{User Accounts}.
10900 If the @code{users} list lacks a user account with UID@tie{}0, a
10901 ``root'' account with UID@tie{}0 is automatically added.
10903 @item @code{skeletons} (default: @code{(default-skeletons)})
10904 A list target file name/file-like object tuples (@pxref{G-Expressions,
10905 file-like objects}). These are the skeleton files that will be added to
10906 the home directory of newly-created user accounts.
10908 For instance, a valid value may look like this:
10911 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
10912 (".guile" ,(plain-file "guile"
10913 "(use-modules (ice-9 readline))
10914 (activate-readline)")))
10917 @item @code{issue} (default: @code{%default-issue})
10918 A string denoting the contents of the @file{/etc/issue} file, which is
10919 displayed when users log in on a text console.
10921 @item @code{packages} (default: @code{%base-packages})
10922 The set of packages installed in the global profile, which is accessible
10923 at @file{/run/current-system/profile}.
10925 The default set includes core utilities and it is good practice to
10926 install non-core utilities in user profiles (@pxref{Invoking guix
10929 @item @code{timezone}
10930 A timezone identifying string---e.g., @code{"Europe/Paris"}.
10932 You can run the @command{tzselect} command to find out which timezone
10933 string corresponds to your region. Choosing an invalid timezone name
10934 causes @command{guix system} to fail.
10936 @item @code{locale} (default: @code{"en_US.utf8"})
10937 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
10938 Library Reference Manual}). @xref{Locales}, for more information.
10940 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
10941 The list of locale definitions to be compiled and that may be used at
10942 run time. @xref{Locales}.
10944 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
10945 The list of GNU@tie{}libc packages whose locale data and tools are used
10946 to build the locale definitions. @xref{Locales}, for compatibility
10947 considerations that justify this option.
10949 @item @code{name-service-switch} (default: @code{%default-nss})
10950 Configuration of the libc name service switch (NSS)---a
10951 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
10954 @item @code{services} (default: @code{%base-services})
10955 A list of service objects denoting system services. @xref{Services}.
10957 @cindex essential services
10958 @item @code{essential-services} (default: ...)
10959 The list of ``essential services''---i.e., things like instances of
10960 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
10961 Reference}), which are derived from the operating system definition itself.
10962 As a user you should @emph{never} need to touch this field.
10964 @item @code{pam-services} (default: @code{(base-pam-services)})
10966 @cindex pluggable authentication modules
10967 Linux @dfn{pluggable authentication module} (PAM) services.
10968 @c FIXME: Add xref to PAM services section.
10970 @item @code{setuid-programs} (default: @var{%setuid-programs})
10971 List of string-valued G-expressions denoting setuid programs.
10972 @xref{Setuid Programs}.
10974 @item @code{sudoers-file} (default: @var{%sudoers-specification})
10975 @cindex sudoers file
10976 The contents of the @file{/etc/sudoers} file as a file-like object
10977 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
10979 This file specifies which users can use the @command{sudo} command, what
10980 they are allowed to do, and what privileges they may gain. The default
10981 is that only @code{root} and members of the @code{wheel} group may use
10986 @deffn {Scheme Syntax} this-operating-system
10987 When used in the @emph{lexical scope} of an operating system field definition,
10988 this identifier resolves to the operating system being defined.
10990 The example below shows how to refer to the operating system being defined in
10991 the definition of the @code{label} field:
10994 (use-modules (gnu) (guix))
10998 (label (package-full-name
10999 (operating-system-kernel this-operating-system))))
11002 It is an error to refer to @code{this-operating-system} outside an operating
11009 @section File Systems
11011 The list of file systems to be mounted is specified in the
11012 @code{file-systems} field of the operating system declaration
11013 (@pxref{Using the Configuration System}). Each file system is declared
11014 using the @code{file-system} form, like this:
11018 (mount-point "/home")
11019 (device "/dev/sda3")
11023 As usual, some of the fields are mandatory---those shown in the example
11024 above---while others can be omitted. These are described below.
11026 @deftp {Data Type} file-system
11027 Objects of this type represent file systems to be mounted. They
11028 contain the following members:
11032 This is a string specifying the type of the file system---e.g.,
11035 @item @code{mount-point}
11036 This designates the place where the file system is to be mounted.
11038 @item @code{device}
11039 This names the ``source'' of the file system. It can be one of three
11040 things: a file system label, a file system UUID, or the name of a
11041 @file{/dev} node. Labels and UUIDs offer a way to refer to file
11042 systems without having to hard-code their actual device
11043 name@footnote{Note that, while it is tempting to use
11044 @file{/dev/disk/by-uuid} and similar device names to achieve the same
11045 result, this is not recommended: These special device nodes are created
11046 by the udev daemon and may be unavailable at the time the device is
11049 @findex file-system-label
11050 File system labels are created using the @code{file-system-label}
11051 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
11052 plain strings. Here's an example of a file system referred to by its
11053 label, as shown by the @command{e2label} command:
11057 (mount-point "/home")
11059 (device (file-system-label "my-home")))
11063 UUIDs are converted from their string representation (as shown by the
11064 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
11065 @code{uuid} form expects 16-byte UUIDs as defined in
11066 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
11067 form of UUID used by the ext2 family of file systems and others, but it
11068 is different from ``UUIDs'' found in FAT file systems, for instance.},
11073 (mount-point "/home")
11075 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
11078 When the source of a file system is a mapped device (@pxref{Mapped
11079 Devices}), its @code{device} field @emph{must} refer to the mapped
11080 device name---e.g., @file{"/dev/mapper/root-partition"}.
11081 This is required so that
11082 the system knows that mounting the file system depends on having the
11083 corresponding device mapping established.
11085 @item @code{flags} (default: @code{'()})
11086 This is a list of symbols denoting mount flags. Recognized flags
11087 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
11088 access to special files), @code{no-suid} (ignore setuid and setgid
11089 bits), @code{no-atime} (do not update file access times), and @code{no-exec}
11090 (disallow program execution). @xref{Mount-Unmount-Remount,,, libc, The GNU C
11091 Library Reference Manual}, for more information on these flags.
11093 @item @code{options} (default: @code{#f})
11094 This is either @code{#f}, or a string denoting mount options passed to the
11095 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
11096 Reference Manual}, for details and run @command{man 8 mount} for options for
11097 various file systems.
11099 @item @code{mount?} (default: @code{#t})
11100 This value indicates whether to automatically mount the file system when
11101 the system is brought up. When set to @code{#f}, the file system gets
11102 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
11103 is not automatically mounted.
11105 @item @code{needed-for-boot?} (default: @code{#f})
11106 This Boolean value indicates whether the file system is needed when
11107 booting. If that is true, then the file system is mounted when the
11108 initial RAM disk (initrd) is loaded. This is always the case, for
11109 instance, for the root file system.
11111 @item @code{check?} (default: @code{#t})
11112 This Boolean indicates whether the file system needs to be checked for
11113 errors before being mounted.
11115 @item @code{create-mount-point?} (default: @code{#f})
11116 When true, the mount point is created if it does not exist yet.
11118 @item @code{dependencies} (default: @code{'()})
11119 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
11120 representing file systems that must be mounted or mapped devices that
11121 must be opened before (and unmounted or closed after) this one.
11123 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
11124 a dependency of @file{/sys/fs/cgroup/cpu} and
11125 @file{/sys/fs/cgroup/memory}.
11127 Another example is a file system that depends on a mapped device, for
11128 example for an encrypted partition (@pxref{Mapped Devices}).
11132 The @code{(gnu system file-systems)} exports the following useful
11135 @defvr {Scheme Variable} %base-file-systems
11136 These are essential file systems that are required on normal systems,
11137 such as @var{%pseudo-terminal-file-system} and @var{%immutable-store} (see
11138 below.) Operating system declarations should always contain at least
11142 @defvr {Scheme Variable} %pseudo-terminal-file-system
11143 This is the file system to be mounted as @file{/dev/pts}. It supports
11144 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
11145 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
11146 Manual}). Pseudo-terminals are used by terminal emulators such as
11150 @defvr {Scheme Variable} %shared-memory-file-system
11151 This file system is mounted as @file{/dev/shm} and is used to support
11152 memory sharing across processes (@pxref{Memory-mapped I/O,
11153 @code{shm_open},, libc, The GNU C Library Reference Manual}).
11156 @defvr {Scheme Variable} %immutable-store
11157 This file system performs a read-only ``bind mount'' of
11158 @file{/gnu/store}, making it read-only for all the users including
11159 @code{root}. This prevents against accidental modification by software
11160 running as @code{root} or by system administrators.
11162 The daemon itself is still able to write to the store: it remounts it
11163 read-write in its own ``name space.''
11166 @defvr {Scheme Variable} %binary-format-file-system
11167 The @code{binfmt_misc} file system, which allows handling of arbitrary
11168 executable file types to be delegated to user space. This requires the
11169 @code{binfmt.ko} kernel module to be loaded.
11172 @defvr {Scheme Variable} %fuse-control-file-system
11173 The @code{fusectl} file system, which allows unprivileged users to mount
11174 and unmount user-space FUSE file systems. This requires the
11175 @code{fuse.ko} kernel module to be loaded.
11178 @node Mapped Devices
11179 @section Mapped Devices
11181 @cindex device mapping
11182 @cindex mapped devices
11183 The Linux kernel has a notion of @dfn{device mapping}: a block device,
11184 such as a hard disk partition, can be @dfn{mapped} into another device,
11185 usually in @code{/dev/mapper/},
11186 with additional processing over the data that flows through
11187 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
11188 concept of a ``mapped device'' and that of a file system: both boil down
11189 to @emph{translating} input/output operations made on a file to
11190 operations on its backing store. Thus, the Hurd implements mapped
11191 devices, like file systems, using the generic @dfn{translator} mechanism
11192 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
11193 typical example is encryption device mapping: all writes to the mapped
11194 device are encrypted, and all reads are deciphered, transparently.
11195 Guix extends this notion by considering any device or set of devices that
11196 are @dfn{transformed} in some way to create a new device; for instance,
11197 RAID devices are obtained by @dfn{assembling} several other devices, such
11198 as hard disks or partitions, into a new one that behaves as one partition.
11199 Other examples, not yet implemented, are LVM logical volumes.
11201 Mapped devices are declared using the @code{mapped-device} form,
11202 defined as follows; for examples, see below.
11204 @deftp {Data Type} mapped-device
11205 Objects of this type represent device mappings that will be made when
11206 the system boots up.
11210 This is either a string specifying the name of the block device to be mapped,
11211 such as @code{"/dev/sda3"}, or a list of such strings when several devices
11212 need to be assembled for creating a new one.
11215 This string specifies the name of the resulting mapped device. For
11216 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
11217 specifying @code{"my-partition"} leads to the creation of
11218 the @code{"/dev/mapper/my-partition"} device.
11219 For RAID devices of type @code{raid-device-mapping}, the full device name
11220 such as @code{"/dev/md0"} needs to be given.
11223 This must be a @code{mapped-device-kind} object, which specifies how
11224 @var{source} is mapped to @var{target}.
11228 @defvr {Scheme Variable} luks-device-mapping
11229 This defines LUKS block device encryption using the @command{cryptsetup}
11230 command from the package with the same name. It relies on the
11231 @code{dm-crypt} Linux kernel module.
11234 @defvr {Scheme Variable} raid-device-mapping
11235 This defines a RAID device, which is assembled using the @code{mdadm}
11236 command from the package with the same name. It requires a Linux kernel
11237 module for the appropriate RAID level to be loaded, such as @code{raid456}
11238 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
11241 @cindex disk encryption
11243 The following example specifies a mapping from @file{/dev/sda3} to
11244 @file{/dev/mapper/home} using LUKS---the
11245 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
11246 standard mechanism for disk encryption.
11247 The @file{/dev/mapper/home}
11248 device can then be used as the @code{device} of a @code{file-system}
11249 declaration (@pxref{File Systems}).
11253 (source "/dev/sda3")
11255 (type luks-device-mapping))
11258 Alternatively, to become independent of device numbering, one may obtain
11259 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11263 cryptsetup luksUUID /dev/sda3
11266 and use it as follows:
11270 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11272 (type luks-device-mapping))
11275 @cindex swap encryption
11276 It is also desirable to encrypt swap space, since swap space may contain
11277 sensitive data. One way to accomplish that is to use a swap file in a
11278 file system on a device mapped via LUKS encryption. In this way, the
11279 swap file is encrypted because the entire device is encrypted.
11280 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11282 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11283 may be declared as follows:
11287 (source (list "/dev/sda1" "/dev/sdb1"))
11288 (target "/dev/md0")
11289 (type raid-device-mapping))
11292 The @file{/dev/md0} device can then be used as the @code{device} of a
11293 @code{file-system} declaration (@pxref{File Systems}).
11294 Note that the RAID level need not be given; it is chosen during the
11295 initial creation and formatting of the RAID device and is determined
11296 automatically later.
11299 @node User Accounts
11300 @section User Accounts
11304 @cindex user accounts
11305 User accounts and groups are entirely managed through the
11306 @code{operating-system} declaration. They are specified with the
11307 @code{user-account} and @code{user-group} forms:
11313 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11314 "audio" ;sound card
11315 "video" ;video devices such as webcams
11316 "cdrom")) ;the good ol' CD-ROM
11317 (comment "Bob's sister")
11318 (home-directory "/home/alice"))
11321 When booting or upon completion of @command{guix system reconfigure},
11322 the system ensures that only the user accounts and groups specified in
11323 the @code{operating-system} declaration exist, and with the specified
11324 properties. Thus, account or group creations or modifications made by
11325 directly invoking commands such as @command{useradd} are lost upon
11326 reconfiguration or reboot. This ensures that the system remains exactly
11329 @deftp {Data Type} user-account
11330 Objects of this type represent user accounts. The following members may
11335 The name of the user account.
11339 This is the name (a string) or identifier (a number) of the user group
11340 this account belongs to.
11342 @item @code{supplementary-groups} (default: @code{'()})
11343 Optionally, this can be defined as a list of group names that this
11344 account belongs to.
11346 @item @code{uid} (default: @code{#f})
11347 This is the user ID for this account (a number), or @code{#f}. In the
11348 latter case, a number is automatically chosen by the system when the
11349 account is created.
11351 @item @code{comment} (default: @code{""})
11352 A comment about the account, such as the account owner's full name.
11354 @item @code{home-directory}
11355 This is the name of the home directory for the account.
11357 @item @code{create-home-directory?} (default: @code{#t})
11358 Indicates whether the home directory of this account should be created
11359 if it does not exist yet.
11361 @item @code{shell} (default: Bash)
11362 This is a G-expression denoting the file name of a program to be used as
11363 the shell (@pxref{G-Expressions}).
11365 @item @code{system?} (default: @code{#f})
11366 This Boolean value indicates whether the account is a ``system''
11367 account. System accounts are sometimes treated specially; for instance,
11368 graphical login managers do not list them.
11370 @anchor{user-account-password}
11371 @cindex password, for user accounts
11372 @item @code{password} (default: @code{#f})
11373 You would normally leave this field to @code{#f}, initialize user
11374 passwords as @code{root} with the @command{passwd} command, and then let
11375 users change it with @command{passwd}. Passwords set with
11376 @command{passwd} are of course preserved across reboot and
11379 If you @emph{do} want to set an initial password for an account, then
11380 this field must contain the encrypted password, as a string. You can use the
11381 @code{crypt} procedure for this purpose:
11388 ;; Specify a SHA-512-hashed initial password.
11389 (password (crypt "InitialPassword!" "$6$abc")))
11393 The hash of this initial password will be available in a file in
11394 @file{/gnu/store}, readable by all the users, so this method must be used with
11398 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11399 more information on password encryption, and @ref{Encryption,,, guile, GNU
11400 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11406 User group declarations are even simpler:
11409 (user-group (name "students"))
11412 @deftp {Data Type} user-group
11413 This type is for, well, user groups. There are just a few fields:
11417 The name of the group.
11419 @item @code{id} (default: @code{#f})
11420 The group identifier (a number). If @code{#f}, a new number is
11421 automatically allocated when the group is created.
11423 @item @code{system?} (default: @code{#f})
11424 This Boolean value indicates whether the group is a ``system'' group.
11425 System groups have low numerical IDs.
11427 @item @code{password} (default: @code{#f})
11428 What, user groups can have a password? Well, apparently yes. Unless
11429 @code{#f}, this field specifies the password of the group.
11434 For convenience, a variable lists all the basic user groups one may
11437 @defvr {Scheme Variable} %base-groups
11438 This is the list of basic user groups that users and/or packages expect
11439 to be present on the system. This includes groups such as ``root'',
11440 ``wheel'', and ``users'', as well as groups used to control access to
11441 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11444 @defvr {Scheme Variable} %base-user-accounts
11445 This is the list of basic system accounts that programs may expect to
11446 find on a GNU/Linux system, such as the ``nobody'' account.
11448 Note that the ``root'' account is not included here. It is a
11449 special-case and is automatically added whether or not it is specified.
11452 @node Keyboard Layout
11453 @section Keyboard Layout
11455 @cindex keyboard layout
11457 To specify what each key of your keyboard does, you need to tell the operating
11458 system what @dfn{keyboard layout} you want to use. The default, when nothing
11459 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11460 However, German speakers will usually prefer the German QWERTZ layout, French
11461 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11462 or bépo, and they might even want to further customize the effect of some of
11463 the keys. This section explains how to get that done.
11465 @cindex keyboard layout, definition
11466 There are three components that will want to know about your keyboard layout:
11470 The @emph{bootloader} may want to know what keyboard layout you want to use
11471 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11472 you want, for instance, to make sure that you can type the passphrase of your
11473 encrypted root partition using the right layout.
11476 The @emph{operating system kernel}, Linux, will need that so that the console
11477 is properly configured (@pxref{operating-system Reference,
11478 @code{keyboard-layout}}).
11481 The @emph{graphical display server}, usually Xorg, also has its own idea of
11482 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11485 Guix allows you to configure all three separately but, fortunately, it allows
11486 you to share the same keyboard layout for all three components.
11488 @cindex XKB, keyboard layouts
11489 Keyboard layouts are represented by records created by the
11490 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11491 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11492 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11493 optional variant name, an optional keyboard model name, and a possibly empty
11494 list of additional options. In most cases the layout name is all you care
11495 about. Here are a few example:
11498 ;; The German QWERTZ layout. Here we assume a standard
11499 ;; "pc105" keyboard model.
11500 (keyboard-layout "de")
11502 ;; The bépo variant of the French layout.
11503 (keyboard-layout "fr" "bepo")
11505 ;; The Catalan layout.
11506 (keyboard-layout "es" "cat")
11508 ;; The Latin American Spanish layout. In addition, the
11509 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11510 ;; and the "Menu" key is used as a "Compose" key to enter
11511 ;; accented letters.
11512 (keyboard-layout "latam"
11513 #:options '("ctrl:nocaps" "compose:menu"))
11515 ;; The Russian layout for a ThinkPad keyboard.
11516 (keyboard-layout "ru" #:model "thinkpad")
11518 ;; The "US international" layout, which is the US layout plus
11519 ;; dead keys to enter accented characters. This is for an
11520 ;; Apple MacBook keyboard.
11521 (keyboard-layout "us" "intl" #:model "macbook78")
11524 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11525 for a complete list of supported layouts, variants, and models.
11527 @cindex keyboard layout, configuration
11528 Let's say you want your system to use the Turkish keyboard layout throughout
11529 your system---bootloader, console, and Xorg. Here's what your system
11530 configuration would look like:
11532 @findex set-xorg-configuration
11534 ;; Using the Turkish layout for the bootloader, the console,
11539 (keyboard-layout (keyboard-layout "tr")) ;for the console
11540 (bootloader (bootloader-configuration
11541 (bootloader grub-efi-bootloader)
11542 (target "/boot/efi")
11543 (keyboard-layout keyboard-layout))) ;for GRUB
11544 (services (cons (set-xorg-configuration
11545 (xorg-configuration ;for Xorg
11546 (keyboard-layout keyboard-layout)))
11547 %desktop-services)))
11550 In the example above, for GRUB and for Xorg, we just refer to the
11551 @code{keyboard-layout} field defined above, but we could just as well refer to
11552 a different layout. The @code{set-xorg-configuration} procedure communicates
11553 the desired Xorg configuration to the graphical log-in manager, by default
11556 We've discussed how to specify the @emph{default} keyboard layout of your
11557 system when it starts, but you can also adjust it at run time:
11561 If you're using GNOME, its settings panel has a ``Region & Language'' entry
11562 where you can select one or more keyboard layouts.
11565 Under Xorg, the @command{setxkbmap} command (from the same-named package)
11566 allows you to change the current layout. For example, this is how you would
11567 change the layout to US Dvorak:
11570 setxkbmap us dvorak
11574 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
11575 console. However, note that @code{loadkeys} does @emph{not} use the XKB
11576 keyboard layout categorization described above. The command below loads the
11577 French bépo layout:
11588 A @dfn{locale} defines cultural conventions for a particular language
11589 and region of the world (@pxref{Locales,,, libc, The GNU C Library
11590 Reference Manual}). Each locale has a name that typically has the form
11591 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
11592 @code{fr_LU.utf8} designates the locale for the French language, with
11593 cultural conventions from Luxembourg, and using the UTF-8 encoding.
11595 @cindex locale definition
11596 Usually, you will want to specify the default locale for the machine
11597 using the @code{locale} field of the @code{operating-system} declaration
11598 (@pxref{operating-system Reference, @code{locale}}).
11600 The selected locale is automatically added to the @dfn{locale
11601 definitions} known to the system if needed, with its codeset inferred
11602 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
11603 @code{UTF-8} codeset. Additional locale definitions can be specified in
11604 the @code{locale-definitions} slot of @code{operating-system}---this is
11605 useful, for instance, if the codeset could not be inferred from the
11606 locale name. The default set of locale definitions includes some widely
11607 used locales, but not all the available locales, in order to save space.
11609 For instance, to add the North Frisian locale for Germany, the value of
11613 (cons (locale-definition
11614 (name "fy_DE.utf8") (source "fy_DE"))
11615 %default-locale-definitions)
11618 Likewise, to save space, one might want @code{locale-definitions} to
11619 list only the locales that are actually used, as in:
11622 (list (locale-definition
11623 (name "ja_JP.eucjp") (source "ja_JP")
11624 (charset "EUC-JP")))
11628 The compiled locale definitions are available at
11629 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
11630 version, which is the default location where the GNU@tie{}libc provided
11631 by Guix looks for locale data. This can be overridden using the
11632 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
11633 @code{LOCPATH} and locale packages}).
11635 The @code{locale-definition} form is provided by the @code{(gnu system
11636 locale)} module. Details are given below.
11638 @deftp {Data Type} locale-definition
11639 This is the data type of a locale definition.
11644 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
11645 Reference Manual}, for more information on locale names.
11647 @item @code{source}
11648 The name of the source for that locale. This is typically the
11649 @code{@var{language}_@var{territory}} part of the locale name.
11651 @item @code{charset} (default: @code{"UTF-8"})
11652 The ``character set'' or ``code set'' for that locale,
11653 @uref{https://www.iana.org/assignments/character-sets, as defined by
11659 @defvr {Scheme Variable} %default-locale-definitions
11660 A list of commonly used UTF-8 locales, used as the default
11661 value of the @code{locale-definitions} field of @code{operating-system}
11664 @cindex locale name
11665 @cindex normalized codeset in locale names
11666 These locale definitions use the @dfn{normalized codeset} for the part
11667 that follows the dot in the name (@pxref{Using gettextized software,
11668 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
11669 instance it has @code{uk_UA.utf8} but @emph{not}, say,
11670 @code{uk_UA.UTF-8}.
11673 @subsection Locale Data Compatibility Considerations
11675 @cindex incompatibility, of locale data
11676 @code{operating-system} declarations provide a @code{locale-libcs} field
11677 to specify the GNU@tie{}libc packages that are used to compile locale
11678 declarations (@pxref{operating-system Reference}). ``Why would I
11679 care?'', you may ask. Well, it turns out that the binary format of
11680 locale data is occasionally incompatible from one libc version to
11683 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
11684 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
11685 For instance, a program linked against libc version 2.21 is unable to
11686 read locale data produced with libc 2.22; worse, that program
11687 @emph{aborts} instead of simply ignoring the incompatible locale
11688 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
11689 the incompatible locale data, which is already an improvement.}.
11690 Similarly, a program linked against libc 2.22 can read most, but not
11691 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
11692 data is incompatible); thus calls to @code{setlocale} may fail, but
11693 programs will not abort.
11695 The ``problem'' with Guix is that users have a lot of freedom: They can
11696 choose whether and when to upgrade software in their profiles, and might
11697 be using a libc version different from the one the system administrator
11698 used to build the system-wide locale data.
11700 Fortunately, unprivileged users can also install their own locale data
11701 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
11702 @code{GUIX_LOCPATH} and locale packages}).
11704 Still, it is best if the system-wide locale data at
11705 @file{/run/current-system/locale} is built for all the libc versions
11706 actually in use on the system, so that all the programs can access
11707 it---this is especially crucial on a multi-user system. To do that, the
11708 administrator can specify several libc packages in the
11709 @code{locale-libcs} field of @code{operating-system}:
11712 (use-package-modules base)
11716 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
11719 This example would lead to a system containing locale definitions for
11720 both libc 2.21 and the current version of libc in
11721 @file{/run/current-system/locale}.
11727 @cindex system services
11728 An important part of preparing an @code{operating-system} declaration is
11729 listing @dfn{system services} and their configuration (@pxref{Using the
11730 Configuration System}). System services are typically daemons launched
11731 when the system boots, or other actions needed at that time---e.g.,
11732 configuring network access.
11734 Guix has a broad definition of ``service'' (@pxref{Service
11735 Composition}), but many services are managed by the GNU@tie{}Shepherd
11736 (@pxref{Shepherd Services}). On a running system, the @command{herd}
11737 command allows you to list the available services, show their status,
11738 start and stop them, or do other specific operations (@pxref{Jump
11739 Start,,, shepherd, The GNU Shepherd Manual}). For example:
11745 The above command, run as @code{root}, lists the currently defined
11746 services. The @command{herd doc} command shows a synopsis of the given
11747 service and its associated actions:
11751 Run libc's name service cache daemon (nscd).
11753 # herd doc nscd action invalidate
11754 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
11757 The @command{start}, @command{stop}, and @command{restart} sub-commands
11758 have the effect you would expect. For instance, the commands below stop
11759 the nscd service and restart the Xorg display server:
11763 Service nscd has been stopped.
11764 # herd restart xorg-server
11765 Service xorg-server has been stopped.
11766 Service xorg-server has been started.
11769 The following sections document the available services, starting with
11770 the core services, that may be used in an @code{operating-system}
11774 * Base Services:: Essential system services.
11775 * Scheduled Job Execution:: The mcron service.
11776 * Log Rotation:: The rottlog service.
11777 * Networking Services:: Network setup, SSH daemon, etc.
11778 * X Window:: Graphical display.
11779 * Printing Services:: Local and remote printer support.
11780 * Desktop Services:: D-Bus and desktop services.
11781 * Sound Services:: ALSA and Pulseaudio services.
11782 * Database Services:: SQL databases, key-value stores, etc.
11783 * Mail Services:: IMAP, POP3, SMTP, and all that.
11784 * Messaging Services:: Messaging services.
11785 * Telephony Services:: Telephony services.
11786 * Monitoring Services:: Monitoring services.
11787 * Kerberos Services:: Kerberos services.
11788 * LDAP Services:: LDAP services.
11789 * Web Services:: Web servers.
11790 * Certificate Services:: TLS certificates via Let's Encrypt.
11791 * DNS Services:: DNS daemons.
11792 * VPN Services:: VPN daemons.
11793 * Network File System:: NFS related services.
11794 * Continuous Integration:: The Cuirass service.
11795 * Power Management Services:: Extending battery life.
11796 * Audio Services:: The MPD.
11797 * Virtualization Services:: Virtualization services.
11798 * Version Control Services:: Providing remote access to Git repositories.
11799 * Game Services:: Game servers.
11800 * Guix Services:: Services relating specifically to Guix.
11801 * Miscellaneous Services:: Other services.
11804 @node Base Services
11805 @subsection Base Services
11807 The @code{(gnu services base)} module provides definitions for the basic
11808 services that one expects from the system. The services exported by
11809 this module are listed below.
11811 @defvr {Scheme Variable} %base-services
11812 This variable contains a list of basic services (@pxref{Service Types
11813 and Services}, for more information on service objects) one would
11814 expect from the system: a login service (mingetty) on each tty, syslogd,
11815 the libc name service cache daemon (nscd), the udev device manager, and
11818 This is the default value of the @code{services} field of
11819 @code{operating-system} declarations. Usually, when customizing a
11820 system, you will want to append services to @code{%base-services}, like
11824 (append (list (service avahi-service-type)
11825 (service openssh-service-type))
11830 @defvr {Scheme Variable} special-files-service-type
11831 This is the service that sets up ``special files'' such as
11832 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
11834 The value associated with @code{special-files-service-type} services
11835 must be a list of tuples where the first element is the ``special file''
11836 and the second element is its target. By default it is:
11838 @cindex @file{/bin/sh}
11839 @cindex @file{sh}, in @file{/bin}
11841 `(("/bin/sh" ,(file-append bash "/bin/sh")))
11844 @cindex @file{/usr/bin/env}
11845 @cindex @file{env}, in @file{/usr/bin}
11846 If you want to add, say, @code{/usr/bin/env} to your system, you can
11850 `(("/bin/sh" ,(file-append bash "/bin/sh"))
11851 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
11854 Since this is part of @code{%base-services}, you can use
11855 @code{modify-services} to customize the set of special files
11856 (@pxref{Service Reference, @code{modify-services}}). But the simple way
11857 to add a special file is @i{via} the @code{extra-special-file} procedure
11861 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
11862 Use @var{target} as the ``special file'' @var{file}.
11864 For example, adding the following lines to the @code{services} field of
11865 your operating system declaration leads to a @file{/usr/bin/env}
11869 (extra-special-file "/usr/bin/env"
11870 (file-append coreutils "/bin/env"))
11874 @deffn {Scheme Procedure} host-name-service @var{name}
11875 Return a service that sets the host name to @var{name}.
11878 @deffn {Scheme Procedure} login-service @var{config}
11879 Return a service to run login according to @var{config}, a
11880 @code{<login-configuration>} object, which specifies the message of the day,
11881 among other things.
11884 @deftp {Data Type} login-configuration
11885 This is the data type representing the configuration of login.
11890 @cindex message of the day
11891 A file-like object containing the ``message of the day''.
11893 @item @code{allow-empty-passwords?} (default: @code{#t})
11894 Allow empty passwords by default so that first-time users can log in when
11895 the 'root' account has just been created.
11900 @deffn {Scheme Procedure} mingetty-service @var{config}
11901 Return a service to run mingetty according to @var{config}, a
11902 @code{<mingetty-configuration>} object, which specifies the tty to run, among
11906 @deftp {Data Type} mingetty-configuration
11907 This is the data type representing the configuration of Mingetty, which
11908 provides the default implementation of virtual console log-in.
11913 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
11915 @item @code{auto-login} (default: @code{#f})
11916 When true, this field must be a string denoting the user name under
11917 which the system automatically logs in. When it is @code{#f}, a
11918 user name and password must be entered to log in.
11920 @item @code{login-program} (default: @code{#f})
11921 This must be either @code{#f}, in which case the default log-in program
11922 is used (@command{login} from the Shadow tool suite), or a gexp denoting
11923 the name of the log-in program.
11925 @item @code{login-pause?} (default: @code{#f})
11926 When set to @code{#t} in conjunction with @var{auto-login}, the user
11927 will have to press a key before the log-in shell is launched.
11929 @item @code{mingetty} (default: @var{mingetty})
11930 The Mingetty package to use.
11935 @deffn {Scheme Procedure} agetty-service @var{config}
11936 Return a service to run agetty according to @var{config}, an
11937 @code{<agetty-configuration>} object, which specifies the tty to run,
11938 among other things.
11941 @deftp {Data Type} agetty-configuration
11942 This is the data type representing the configuration of agetty, which
11943 implements virtual and serial console log-in. See the @code{agetty(8)}
11944 man page for more information.
11949 The name of the console this agetty runs on, as a string---e.g.,
11950 @code{"ttyS0"}. This argument is optional, it will default to
11951 a reasonable default serial port used by the kernel Linux.
11953 For this, if there is a value for an option @code{agetty.tty} in the kernel
11954 command line, agetty will extract the device name of the serial port
11955 from it and use that.
11957 If not and if there is a value for an option @code{console} with a tty in
11958 the Linux command line, agetty will extract the device name of the
11959 serial port from it and use that.
11961 In both cases, agetty will leave the other serial device settings
11962 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
11965 @item @code{baud-rate} (default: @code{#f})
11966 A string containing a comma-separated list of one or more baud rates, in
11969 @item @code{term} (default: @code{#f})
11970 A string containing the value used for the @code{TERM} environment
11973 @item @code{eight-bits?} (default: @code{#f})
11974 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
11977 @item @code{auto-login} (default: @code{#f})
11978 When passed a login name, as a string, the specified user will be logged
11979 in automatically without prompting for their login name or password.
11981 @item @code{no-reset?} (default: @code{#f})
11982 When @code{#t}, don't reset terminal cflags (control modes).
11984 @item @code{host} (default: @code{#f})
11985 This accepts a string containing the "login_host", which will be written
11986 into the @file{/var/run/utmpx} file.
11988 @item @code{remote?} (default: @code{#f})
11989 When set to @code{#t} in conjunction with @var{host}, this will add an
11990 @code{-r} fakehost option to the command line of the login program
11991 specified in @var{login-program}.
11993 @item @code{flow-control?} (default: @code{#f})
11994 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
11996 @item @code{no-issue?} (default: @code{#f})
11997 When set to @code{#t}, the contents of the @file{/etc/issue} file will
11998 not be displayed before presenting the login prompt.
12000 @item @code{init-string} (default: @code{#f})
12001 This accepts a string that will be sent to the tty or modem before
12002 sending anything else. It can be used to initialize a modem.
12004 @item @code{no-clear?} (default: @code{#f})
12005 When set to @code{#t}, agetty will not clear the screen before showing
12008 @item @code{login-program} (default: (file-append shadow "/bin/login"))
12009 This must be either a gexp denoting the name of a log-in program, or
12010 unset, in which case the default value is the @command{login} from the
12013 @item @code{local-line} (default: @code{#f})
12014 Control the CLOCAL line flag. This accepts one of three symbols as
12015 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
12016 the default value chosen by agetty is @code{'auto}.
12018 @item @code{extract-baud?} (default: @code{#f})
12019 When set to @code{#t}, instruct agetty to try to extract the baud rate
12020 from the status messages produced by certain types of modems.
12022 @item @code{skip-login?} (default: @code{#f})
12023 When set to @code{#t}, do not prompt the user for a login name. This
12024 can be used with @var{login-program} field to use non-standard login
12027 @item @code{no-newline?} (default: @code{#f})
12028 When set to @code{#t}, do not print a newline before printing the
12029 @file{/etc/issue} file.
12031 @c Is this dangerous only when used with login-program, or always?
12032 @item @code{login-options} (default: @code{#f})
12033 This option accepts a string containing options that are passed to the
12034 login program. When used with the @var{login-program}, be aware that a
12035 malicious user could try to enter a login name containing embedded
12036 options that could be parsed by the login program.
12038 @item @code{login-pause} (default: @code{#f})
12039 When set to @code{#t}, wait for any key before showing the login prompt.
12040 This can be used in conjunction with @var{auto-login} to save memory by
12041 lazily spawning shells.
12043 @item @code{chroot} (default: @code{#f})
12044 Change root to the specified directory. This option accepts a directory
12047 @item @code{hangup?} (default: @code{#f})
12048 Use the Linux system call @code{vhangup} to do a virtual hangup of the
12049 specified terminal.
12051 @item @code{keep-baud?} (default: @code{#f})
12052 When set to @code{#t}, try to keep the existing baud rate. The baud
12053 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
12056 @item @code{timeout} (default: @code{#f})
12057 When set to an integer value, terminate if no user name could be read
12058 within @var{timeout} seconds.
12060 @item @code{detect-case?} (default: @code{#f})
12061 When set to @code{#t}, turn on support for detecting an uppercase-only
12062 terminal. This setting will detect a login name containing only
12063 uppercase letters as indicating an uppercase-only terminal and turn on
12064 some upper-to-lower case conversions. Note that this will not support
12065 Unicode characters.
12067 @item @code{wait-cr?} (default: @code{#f})
12068 When set to @code{#t}, wait for the user or modem to send a
12069 carriage-return or linefeed character before displaying
12070 @file{/etc/issue} or login prompt. This is typically used with the
12071 @var{init-string} option.
12073 @item @code{no-hints?} (default: @code{#f})
12074 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
12077 @item @code{no-hostname?} (default: @code{#f})
12078 By default, the hostname is printed. When this option is set to
12079 @code{#t}, no hostname will be shown at all.
12081 @item @code{long-hostname?} (default: @code{#f})
12082 By default, the hostname is only printed until the first dot. When this
12083 option is set to @code{#t}, the fully qualified hostname by
12084 @code{gethostname} or @code{getaddrinfo} is shown.
12086 @item @code{erase-characters} (default: @code{#f})
12087 This option accepts a string of additional characters that should be
12088 interpreted as backspace when the user types their login name.
12090 @item @code{kill-characters} (default: @code{#f})
12091 This option accepts a string that should be interpreted to mean "ignore
12092 all previous characters" (also called a "kill" character) when the user
12093 types their login name.
12095 @item @code{chdir} (default: @code{#f})
12096 This option accepts, as a string, a directory path that will be changed
12099 @item @code{delay} (default: @code{#f})
12100 This options accepts, as an integer, the number of seconds to sleep
12101 before opening the tty and displaying the login prompt.
12103 @item @code{nice} (default: @code{#f})
12104 This option accepts, as an integer, the nice value with which to run the
12105 @command{login} program.
12107 @item @code{extra-options} (default: @code{'()})
12108 This option provides an "escape hatch" for the user to provide arbitrary
12109 command-line arguments to @command{agetty} as a list of strings.
12114 @deffn {Scheme Procedure} kmscon-service-type @var{config}
12115 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
12116 according to @var{config}, a @code{<kmscon-configuration>} object, which
12117 specifies the tty to run, among other things.
12120 @deftp {Data Type} kmscon-configuration
12121 This is the data type representing the configuration of Kmscon, which
12122 implements virtual console log-in.
12126 @item @code{virtual-terminal}
12127 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
12129 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
12130 A gexp denoting the name of the log-in program. The default log-in program is
12131 @command{login} from the Shadow tool suite.
12133 @item @code{login-arguments} (default: @code{'("-p")})
12134 A list of arguments to pass to @command{login}.
12136 @item @code{auto-login} (default: @code{#f})
12137 When passed a login name, as a string, the specified user will be logged
12138 in automatically without prompting for their login name or password.
12140 @item @code{hardware-acceleration?} (default: #f)
12141 Whether to use hardware acceleration.
12143 @item @code{kmscon} (default: @var{kmscon})
12144 The Kmscon package to use.
12149 @cindex name service cache daemon
12151 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
12152 [#:name-services '()]
12153 Return a service that runs the libc name service cache daemon (nscd) with the
12154 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
12155 Service Switch}, for an example.
12157 For convenience, the Shepherd service for nscd provides the following actions:
12161 @cindex cache invalidation, nscd
12162 @cindex nscd, cache invalidation
12163 This invalidate the given cache. For instance, running:
12166 herd invalidate nscd hosts
12170 invalidates the host name lookup cache of nscd.
12173 Running @command{herd statistics nscd} displays information about nscd usage
12179 @defvr {Scheme Variable} %nscd-default-configuration
12180 This is the default @code{<nscd-configuration>} value (see below) used
12181 by @code{nscd-service}. It uses the caches defined by
12182 @var{%nscd-default-caches}; see below.
12185 @deftp {Data Type} nscd-configuration
12186 This is the data type representing the name service cache daemon (nscd)
12191 @item @code{name-services} (default: @code{'()})
12192 List of packages denoting @dfn{name services} that must be visible to
12193 the nscd---e.g., @code{(list @var{nss-mdns})}.
12195 @item @code{glibc} (default: @var{glibc})
12196 Package object denoting the GNU C Library providing the @command{nscd}
12199 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
12200 Name of the nscd log file. This is where debugging output goes when
12201 @code{debug-level} is strictly positive.
12203 @item @code{debug-level} (default: @code{0})
12204 Integer denoting the debugging levels. Higher numbers mean that more
12205 debugging output is logged.
12207 @item @code{caches} (default: @var{%nscd-default-caches})
12208 List of @code{<nscd-cache>} objects denoting things to be cached; see
12214 @deftp {Data Type} nscd-cache
12215 Data type representing a cache database of nscd and its parameters.
12219 @item @code{database}
12220 This is a symbol representing the name of the database to be cached.
12221 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
12222 @code{services}, which designate the corresponding NSS database
12223 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
12225 @item @code{positive-time-to-live}
12226 @itemx @code{negative-time-to-live} (default: @code{20})
12227 A number representing the number of seconds during which a positive or
12228 negative lookup result remains in cache.
12230 @item @code{check-files?} (default: @code{#t})
12231 Whether to check for updates of the files corresponding to
12234 For instance, when @var{database} is @code{hosts}, setting this flag
12235 instructs nscd to check for updates in @file{/etc/hosts} and to take
12238 @item @code{persistent?} (default: @code{#t})
12239 Whether the cache should be stored persistently on disk.
12241 @item @code{shared?} (default: @code{#t})
12242 Whether the cache should be shared among users.
12244 @item @code{max-database-size} (default: 32@tie{}MiB)
12245 Maximum size in bytes of the database cache.
12247 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
12248 @c settings, so leave them out.
12253 @defvr {Scheme Variable} %nscd-default-caches
12254 List of @code{<nscd-cache>} objects used by default by
12255 @code{nscd-configuration} (see above).
12257 It enables persistent and aggressive caching of service and host name
12258 lookups. The latter provides better host name lookup performance,
12259 resilience in the face of unreliable name servers, and also better
12260 privacy---often the result of host name lookups is in local cache, so
12261 external name servers do not even need to be queried.
12264 @anchor{syslog-configuration-type}
12267 @deftp {Data Type} syslog-configuration
12268 This data type represents the configuration of the syslog daemon.
12271 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12272 The syslog daemon to use.
12274 @item @code{config-file} (default: @code{%default-syslog.conf})
12275 The syslog configuration file to use.
12280 @anchor{syslog-service}
12282 @deffn {Scheme Procedure} syslog-service @var{config}
12283 Return a service that runs a syslog daemon according to @var{config}.
12285 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12286 information on the configuration file syntax.
12289 @defvr {Scheme Variable} guix-service-type
12290 This is the type of the service that runs the build daemon,
12291 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12292 @code{guix-configuration} record as described below.
12295 @anchor{guix-configuration-type}
12296 @deftp {Data Type} guix-configuration
12297 This data type represents the configuration of the Guix build daemon.
12298 @xref{Invoking guix-daemon}, for more information.
12301 @item @code{guix} (default: @var{guix})
12302 The Guix package to use.
12304 @item @code{build-group} (default: @code{"guixbuild"})
12305 Name of the group for build user accounts.
12307 @item @code{build-accounts} (default: @code{10})
12308 Number of build user accounts to create.
12310 @item @code{authorize-key?} (default: @code{#t})
12311 @cindex substitutes, authorization thereof
12312 Whether to authorize the substitute keys listed in
12313 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12314 (@pxref{Substitutes}).
12316 @vindex %default-authorized-guix-keys
12317 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12318 The list of authorized key files for archive imports, as a list of
12319 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12320 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12322 @item @code{use-substitutes?} (default: @code{#t})
12323 Whether to use substitutes.
12325 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12326 The list of URLs where to look for substitutes by default.
12328 @item @code{max-silent-time} (default: @code{0})
12329 @itemx @code{timeout} (default: @code{0})
12330 The number of seconds of silence and the number of seconds of activity,
12331 respectively, after which a build process times out. A value of zero
12332 disables the timeout.
12334 @item @code{log-compression} (default: @code{'bzip2})
12335 The type of compression used for build logs---one of @code{gzip},
12336 @code{bzip2}, or @code{none}.
12338 @item @code{extra-options} (default: @code{'()})
12339 List of extra command-line options for @command{guix-daemon}.
12341 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12342 File where @command{guix-daemon}'s standard output and standard error
12345 @item @code{http-proxy} (default: @code{#f})
12346 The HTTP proxy used for downloading fixed-output derivations and
12349 @item @code{tmpdir} (default: @code{#f})
12350 A directory path where the @command{guix-daemon} will perform builds.
12355 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12356 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12357 udev rules can be provided as a list of files through the @var{rules}
12358 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12359 @code{(gnu services base)} simplify the creation of such rule files.
12362 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12363 Return a udev-rule file named @var{file-name} containing the rules
12364 defined by the @var{contents} literal.
12366 In the following example, a rule for a USB device is defined to be
12367 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12368 upon detecting a USB device with a given product identifier.
12371 (define %example-udev-rule
12373 "90-usb-thing.rules"
12374 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12375 "ATTR@{product@}==\"Example\", "
12376 "RUN+=\"/path/to/script\"")))
12379 The @command{herd rules udev} command, as root, returns the name of the
12380 directory containing all the active udev rules.
12383 Here we show how the default @var{udev-service} can be extended with it.
12389 (modify-services %desktop-services
12390 (udev-service-type config =>
12391 (udev-configuration (inherit config)
12392 (rules (append (udev-configuration-rules config)
12393 (list %example-udev-rule))))))))
12396 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12397 Return a udev file named @var{file-name} containing the rules defined
12398 within @var{file}, a file-like object.
12400 The following example showcases how we can use an existing rule file.
12403 (use-modules (guix download) ;for url-fetch
12404 (guix packages) ;for origin
12407 (define %android-udev-rules
12409 "51-android-udev.rules"
12410 (let ((version "20170910"))
12413 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12414 "android-udev-rules/" version "/51-android.rules"))
12416 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12420 Additionally, Guix package definitions can be included in @var{rules} in
12421 order to extend the udev rules with the definitions found under their
12422 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12423 @var{file->udev-rule} example, we could have used the
12424 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12425 packages android)} module.
12427 The following example shows how to use the @var{android-udev-rules}
12428 package so that the Android tool @command{adb} can detect devices
12429 without root privileges. It also details how to create the
12430 @code{adbusers} group, which is required for the proper functioning of
12431 the rules defined within the @var{android-udev-rules} package. To
12432 create such a group, we must define it both as part of the
12433 @var{supplementary-groups} of our @var{user-account} declaration, as
12434 well as in the @var{groups} field of the @var{operating-system} record.
12437 (use-modules (gnu packages android) ;for android-udev-rules
12438 (gnu system shadow) ;for user-group
12443 (users (cons (user-acount
12445 (supplementary-groups
12446 '("adbusers" ;for adb
12447 "wheel" "netdev" "audio" "video")))))
12449 (groups (cons (user-group (system? #t) (name "adbusers"))
12455 (modify-services %desktop-services
12458 (udev-configuration (inherit config)
12459 (rules (cons android-udev-rules
12460 (udev-configuration-rules config))))))))
12463 @defvr {Scheme Variable} urandom-seed-service-type
12464 Save some entropy in @var{%random-seed-file} to seed @file{/dev/urandom}
12465 when rebooting. It also tries to seed @file{/dev/urandom} from
12466 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12470 @defvr {Scheme Variable} %random-seed-file
12471 This is the name of the file where some random bytes are saved by
12472 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12473 It defaults to @file{/var/lib/random-seed}.
12478 @defvr {Scheme Variable} gpm-service-type
12479 This is the type of the service that runs GPM, the @dfn{general-purpose
12480 mouse daemon}, which provides mouse support to the Linux console. GPM
12481 allows users to use the mouse in the console, notably to select, copy,
12484 The value for services of this type must be a @code{gpm-configuration}
12485 (see below). This service is not part of @code{%base-services}.
12488 @deftp {Data Type} gpm-configuration
12489 Data type representing the configuration of GPM.
12492 @item @code{options} (default: @code{%default-gpm-options})
12493 Command-line options passed to @command{gpm}. The default set of
12494 options instruct @command{gpm} to listen to mouse events on
12495 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12498 @item @code{gpm} (default: @code{gpm})
12499 The GPM package to use.
12504 @anchor{guix-publish-service-type}
12505 @deffn {Scheme Variable} guix-publish-service-type
12506 This is the service type for @command{guix publish} (@pxref{Invoking
12507 guix publish}). Its value must be a @code{guix-publish-configuration}
12508 object, as described below.
12510 This assumes that @file{/etc/guix} already contains a signing key pair as
12511 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12512 archive}). If that is not the case, the service will fail to start.
12515 @deftp {Data Type} guix-publish-configuration
12516 Data type representing the configuration of the @code{guix publish}
12520 @item @code{guix} (default: @code{guix})
12521 The Guix package to use.
12523 @item @code{port} (default: @code{80})
12524 The TCP port to listen for connections.
12526 @item @code{host} (default: @code{"localhost"})
12527 The host (and thus, network interface) to listen to. Use
12528 @code{"0.0.0.0"} to listen on all the network interfaces.
12530 @item @code{compression} (default: @code{'(("gzip" 3))})
12531 This is a list of compression method/level tuple used when compressing
12532 substitutes. For example, to compress all substitutes with @emph{both} lzip
12533 at level 7 and gzip at level 9, write:
12536 '(("lzip" 7) ("gzip" 9))
12539 Level 9 achieves the best compression ratio at the expense of increased CPU
12540 usage, whereas level 1 achieves fast compression.
12542 An empty list disables compression altogether.
12544 @item @code{nar-path} (default: @code{"nar"})
12545 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
12546 publish, @code{--nar-path}}, for details.
12548 @item @code{cache} (default: @code{#f})
12549 When it is @code{#f}, disable caching and instead generate archives on
12550 demand. Otherwise, this should be the name of a directory---e.g.,
12551 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
12552 archives and meta-data ready to be sent. @xref{Invoking guix publish,
12553 @option{--cache}}, for more information on the tradeoffs involved.
12555 @item @code{workers} (default: @code{#f})
12556 When it is an integer, this is the number of worker threads used for
12557 caching; when @code{#f}, the number of processors is used.
12558 @xref{Invoking guix publish, @option{--workers}}, for more information.
12560 @item @code{ttl} (default: @code{#f})
12561 When it is an integer, this denotes the @dfn{time-to-live} in seconds
12562 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
12563 for more information.
12567 @anchor{rngd-service}
12568 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
12569 [#:device "/dev/hwrng"]
12570 Return a service that runs the @command{rngd} program from @var{rng-tools}
12571 to add @var{device} to the kernel's entropy pool. The service will fail if
12572 @var{device} does not exist.
12575 @anchor{pam-limits-service}
12576 @cindex session limits
12581 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
12583 Return a service that installs a configuration file for the
12584 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
12585 @code{pam_limits} module}. The procedure optionally takes a list of
12586 @code{pam-limits-entry} values, which can be used to specify
12587 @code{ulimit} limits and nice priority limits to user sessions.
12589 The following limits definition sets two hard and soft limits for all
12590 login sessions of users in the @code{realtime} group:
12593 (pam-limits-service
12595 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
12596 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
12599 The first entry increases the maximum realtime priority for
12600 non-privileged processes; the second entry lifts any restriction of the
12601 maximum address space that can be locked in memory. These settings are
12602 commonly used for real-time audio systems.
12605 @node Scheduled Job Execution
12606 @subsection Scheduled Job Execution
12610 @cindex scheduling jobs
12611 The @code{(gnu services mcron)} module provides an interface to
12612 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
12613 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
12614 Unix @command{cron} daemon; the main difference is that it is
12615 implemented in Guile Scheme, which provides a lot of flexibility when
12616 specifying the scheduling of jobs and their actions.
12618 The example below defines an operating system that runs the
12619 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
12620 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
12621 well as the @command{mkid} command on behalf of an unprivileged user
12622 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
12623 gexps to introduce job definitions that are passed to mcron
12624 (@pxref{G-Expressions}).
12627 (use-modules (guix) (gnu) (gnu services mcron))
12628 (use-package-modules base idutils)
12630 (define updatedb-job
12631 ;; Run 'updatedb' at 3AM every day. Here we write the
12632 ;; job's action as a Scheme procedure.
12633 #~(job '(next-hour '(3))
12635 (execl (string-append #$findutils "/bin/updatedb")
12637 "--prunepaths=/tmp /var/tmp /gnu/store"))))
12639 (define garbage-collector-job
12640 ;; Collect garbage 5 minutes after midnight every day.
12641 ;; The job's action is a shell command.
12642 #~(job "5 0 * * *" ;Vixie cron syntax
12645 (define idutils-job
12646 ;; Update the index database as user "charlie" at 12:15PM
12647 ;; and 19:15PM. This runs from the user's home directory.
12648 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
12649 (string-append #$idutils "/bin/mkid src")
12654 (services (cons (service mcron-service-type
12655 (mcron-configuration
12656 (jobs (list garbage-collector-job
12662 For more complex jobs defined in Scheme where you need control over the top
12663 level, for instance to introduce a @code{use-modules} form, you can move your
12664 code to a separate program using the @code{program-file} procedure of the
12665 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
12669 (define %battery-alert-job
12670 ;; Beep when the battery percentage falls below %MIN-LEVEL.
12672 '(next-minute (range 0 60 1))
12674 "battery-alert.scm"
12675 (with-imported-modules (source-module-closure
12676 '((guix build utils)))
12678 (define %min-level 20)
12679 (use-modules (guix build utils)
12682 (ice-9 textual-ports)
12684 (setenv "LC_ALL" "C") ;ensure English output
12685 (and-let* ((input-pipe (open-pipe*
12687 #$(file-append acpi "/bin/acpi")))
12688 (output (get-string-all input-pipe))
12689 (m (string-match "Discharging, ([0-9]+)%" output))
12690 (level (string->number (match:substring m 1)))
12691 ((< level %min-level)))
12692 (format #t "warning: Battery level is low (~a%)~%" level)
12693 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
12696 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
12697 for more information on mcron job specifications. Below is the
12698 reference of the mcron service.
12700 On a running system, you can use the @code{schedule} action of the service to
12701 visualize the mcron jobs that will be executed next:
12704 # herd schedule mcron
12708 The example above lists the next five tasks that will be executed, but you can
12709 also specify the number of tasks to display:
12712 # herd schedule mcron 10
12715 @defvr {Scheme Variable} mcron-service-type
12716 This is the type of the @code{mcron} service, whose value is an
12717 @code{mcron-configuration} object.
12719 This service type can be the target of a service extension that provides
12720 it additional job specifications (@pxref{Service Composition}). In
12721 other words, it is possible to define services that provide additional
12725 @deftp {Data Type} mcron-configuration
12726 Data type representing the configuration of mcron.
12729 @item @code{mcron} (default: @var{mcron})
12730 The mcron package to use.
12733 This is a list of gexps (@pxref{G-Expressions}), where each gexp
12734 corresponds to an mcron job specification (@pxref{Syntax, mcron job
12735 specifications,, mcron, GNU@tie{}mcron}).
12741 @subsection Log Rotation
12744 @cindex log rotation
12746 Log files such as those found in @file{/var/log} tend to grow endlessly,
12747 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
12748 their contents in separate files, possibly compressed. The @code{(gnu
12749 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
12750 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
12752 The example below defines an operating system that provides log rotation
12753 with the default settings, for commonly encountered log files.
12756 (use-modules (guix) (gnu))
12757 (use-service-modules admin mcron)
12758 (use-package-modules base idutils)
12762 (services (cons (service rottlog-service-type)
12766 @defvr {Scheme Variable} rottlog-service-type
12767 This is the type of the Rottlog service, whose value is a
12768 @code{rottlog-configuration} object.
12770 Other services can extend this one with new @code{log-rotation} objects
12771 (see below), thereby augmenting the set of files to be rotated.
12773 This service type can define mcron jobs (@pxref{Scheduled Job
12774 Execution}) to run the rottlog service.
12777 @deftp {Data Type} rottlog-configuration
12778 Data type representing the configuration of rottlog.
12781 @item @code{rottlog} (default: @code{rottlog})
12782 The Rottlog package to use.
12784 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
12785 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
12786 rottlog, GNU Rot[t]log Manual}).
12788 @item @code{rotations} (default: @code{%default-rotations})
12789 A list of @code{log-rotation} objects as defined below.
12792 This is a list of gexps where each gexp corresponds to an mcron job
12793 specification (@pxref{Scheduled Job Execution}).
12797 @deftp {Data Type} log-rotation
12798 Data type representing the rotation of a group of log files.
12800 Taking an example from the Rottlog manual (@pxref{Period Related File
12801 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
12807 (files '("/var/log/apache/*"))
12808 (options '("storedir apache-archives"
12814 The list of fields is as follows:
12817 @item @code{frequency} (default: @code{'weekly})
12818 The log rotation frequency, a symbol.
12821 The list of files or file glob patterns to rotate.
12823 @item @code{options} (default: @code{'()})
12824 The list of rottlog options for this rotation (@pxref{Configuration
12825 parameters,,, rottlog, GNU Rot[t]lg Manual}).
12827 @item @code{post-rotate} (default: @code{#f})
12828 Either @code{#f} or a gexp to execute once the rotation has completed.
12832 @defvr {Scheme Variable} %default-rotations
12833 Specifies weekly rotation of @var{%rotated-files} and of
12834 @file{/var/log/guix-daemon.log}.
12837 @defvr {Scheme Variable} %rotated-files
12838 The list of syslog-controlled files to be rotated. By default it is:
12839 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
12840 "/var/log/maillog")}.
12843 @node Networking Services
12844 @subsection Networking Services
12846 The @code{(gnu services networking)} module provides services to configure
12847 the network interface.
12849 @cindex DHCP, networking service
12850 @defvr {Scheme Variable} dhcp-client-service-type
12851 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
12852 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
12853 is the DHCP client package to use, @code{isc-dhcp} by default.
12856 @deffn {Scheme Procedure} dhcpd-service-type
12857 This type defines a service that runs a DHCP daemon. To create a
12858 service of this type, you must supply a @code{<dhcpd-configuration>}.
12862 (service dhcpd-service-type
12863 (dhcpd-configuration
12864 (config-file (local-file "my-dhcpd.conf"))
12865 (interfaces '("enp0s25"))))
12869 @deftp {Data Type} dhcpd-configuration
12871 @item @code{package} (default: @code{isc-dhcp})
12872 The package that provides the DHCP daemon. This package is expected to
12873 provide the daemon at @file{sbin/dhcpd} relative to its output
12874 directory. The default package is the
12875 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
12876 @item @code{config-file} (default: @code{#f})
12877 The configuration file to use. This is required. It will be passed to
12878 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
12879 object (@pxref{G-Expressions, file-like objects}). See @code{man
12880 dhcpd.conf} for details on the configuration file syntax.
12881 @item @code{version} (default: @code{"4"})
12882 The DHCP version to use. The ISC DHCP server supports the values ``4'',
12883 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
12884 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
12886 @item @code{run-directory} (default: @code{"/run/dhcpd"})
12887 The run directory to use. At service activation time, this directory
12888 will be created if it does not exist.
12889 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
12890 The PID file to use. This corresponds to the @code{-pf} option of
12891 @code{dhcpd}. See @code{man dhcpd} for details.
12892 @item @code{interfaces} (default: @code{'()})
12893 The names of the network interfaces on which dhcpd should listen for
12894 broadcasts. If this list is not empty, then its elements (which must be
12895 strings) will be appended to the @code{dhcpd} invocation when starting
12896 the daemon. It may not be necessary to explicitly specify any
12897 interfaces here; see @code{man dhcpd} for details.
12901 @defvr {Scheme Variable} static-networking-service-type
12902 This is the type for statically-configured network interfaces.
12903 @c TODO Document <static-networking> data structures.
12906 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
12907 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
12908 [#:requirement @code{'(udev)}]
12909 Return a service that starts @var{interface} with address @var{ip}. If
12910 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
12911 it must be a string specifying the default network gateway. @var{requirement}
12912 can be used to declare a dependency on another service before configuring the
12915 This procedure can be called several times, one for each network
12916 interface of interest. Behind the scenes what it does is extend
12917 @code{static-networking-service-type} with additional network interfaces
12923 (static-networking-service "eno1" "192.168.1.82"
12924 #:gateway "192.168.1.2"
12925 #:name-servers '("192.168.1.2"))
12932 @cindex network management
12933 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
12934 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
12935 management daemon that aims to simplify wired and wireless networking.
12937 This service adds the @var{wicd} package to the global profile, providing
12938 several commands to interact with the daemon and configure networking:
12939 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
12940 and @command{wicd-curses} user interfaces.
12943 @cindex ModemManager
12945 @defvr {Scheme Variable} modem-manager-service-type
12946 This is the service type for the
12947 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
12948 service. The value for this service type is a
12949 @code{modem-manager-configuration} record.
12951 This service is part of @code{%desktop-services} (@pxref{Desktop
12955 @deftp {Data Type} modem-manager-configuration
12956 Data type representing the configuration of ModemManager.
12959 @item @code{modem-manager} (default: @code{modem-manager})
12960 The ModemManager package to use.
12965 @cindex USB_ModeSwitch
12966 @cindex Modeswitching
12968 @defvr {Scheme Variable} usb-modeswitch-service-type
12969 This is the service type for the
12970 @uref{http://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
12971 value for this service type is a @code{usb-modeswitch-configuration} record.
12973 When plugged in, some USB modems (and other USB devices) initially present
12974 themselves as a read-only storage medium and not as a modem. They need to be
12975 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
12976 installs udev rules to automatically modeswitch these devices when they are
12979 This service is part of @code{%desktop-services} (@pxref{Desktop
12983 @deftp {Data Type} usb-modeswitch-configuration
12984 Data type representing the configuration of USB_ModeSwitch.
12987 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
12988 The USB_ModeSwitch package providing the binaries for modeswitching.
12990 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
12991 The package providing the device data and udev rules file used by
12994 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
12995 Which config file to use for the USB_ModeSwitch dispatcher. By default the
12996 config file shipped with USB_ModeSwitch is used which disables logging to
12997 @file{/var/log} among other default settings. If set to @code{#f}, no config
13003 @cindex NetworkManager
13005 @defvr {Scheme Variable} network-manager-service-type
13006 This is the service type for the
13007 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
13008 service. The value for this service type is a
13009 @code{network-manager-configuration} record.
13011 This service is part of @code{%desktop-services} (@pxref{Desktop
13015 @deftp {Data Type} network-manager-configuration
13016 Data type representing the configuration of NetworkManager.
13019 @item @code{network-manager} (default: @code{network-manager})
13020 The NetworkManager package to use.
13022 @item @code{dns} (default: @code{"default"})
13023 Processing mode for DNS, which affects how NetworkManager uses the
13024 @code{resolv.conf} configuration file.
13028 NetworkManager will update @code{resolv.conf} to reflect the nameservers
13029 provided by currently active connections.
13032 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
13033 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
13034 then update @code{resolv.conf} to point to the local nameserver.
13036 With this setting, you can share your network connection. For example when
13037 you want to share your network connection to another laptop @i{via} an
13038 Ethernet cable, you can open @command{nm-connection-editor} and configure the
13039 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
13040 and reestablish the connection (or reboot).
13042 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
13043 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
13044 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
13045 browser on your host system, or connect to the VM @i{via} SSH
13046 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
13047 host-to-guest connection, run this command once:
13050 nmcli connection add type tun \
13051 connection.interface-name tap0 \
13052 tun.mode tap tun.owner $(id -u) \
13053 ipv4.method shared \
13054 ipv4.addresses 172.28.112.1/24
13057 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
13058 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
13059 @command{qemu-system-...}.
13062 NetworkManager will not modify @code{resolv.conf}.
13065 @item @code{vpn-plugins} (default: @code{'()})
13066 This is the list of available plugins for virtual private networks
13067 (VPNs). An example of this is the @code{network-manager-openvpn}
13068 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
13074 @deffn {Scheme Variable} connman-service-type
13075 This is the service type to run @url{https://01.org/connman,Connman},
13076 a network connection manager.
13078 Its value must be an
13079 @code{connman-configuration} record as in this example:
13082 (service connman-service-type
13083 (connman-configuration
13084 (disable-vpn? #t)))
13087 See below for details about @code{connman-configuration}.
13090 @deftp {Data Type} connman-configuration
13091 Data Type representing the configuration of connman.
13094 @item @code{connman} (default: @var{connman})
13095 The connman package to use.
13097 @item @code{disable-vpn?} (default: @code{#f})
13098 When true, disable connman's vpn plugin.
13102 @cindex WPA Supplicant
13103 @defvr {Scheme Variable} wpa-supplicant-service-type
13104 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
13105 supplicant}, an authentication daemon required to authenticate against
13106 encrypted WiFi or ethernet networks.
13109 @deftp {Data Type} wpa-supplicant-configuration
13110 Data type representing the configuration of WPA Supplicant.
13112 It takes the following parameters:
13115 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
13116 The WPA Supplicant package to use.
13118 @item @code{dbus?} (default: @code{#t})
13119 Whether to listen for requests on D-Bus.
13121 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
13122 Where to store the PID file.
13124 @item @code{interface} (default: @code{#f})
13125 If this is set, it must specify the name of a network interface that
13126 WPA supplicant will control.
13128 @item @code{config-file} (default: @code{#f})
13129 Optional configuration file to use.
13131 @item @code{extra-options} (default: @code{'()})
13132 List of additional command-line arguments to pass to the daemon.
13137 @defvr {Scheme Variable} iptables-service-type
13138 This is the service type to set up an iptables configuration. iptables is a
13139 packet filtering framework supported by the Linux kernel. This service
13140 supports configuring iptables for both IPv4 and IPv6. A simple example
13141 configuration rejecting all incoming connections except those to the ssh port
13145 (service iptables-service-type
13146 (iptables-configuration
13147 (ipv4-rules (plain-file "iptables.rules" "*filter
13151 -A INPUT -p tcp --dport 22 -j ACCEPT
13152 -A INPUT -j REJECT --reject-with icmp-port-unreachable
13155 (ipv6-rules (plain-file "ip6tables.rules" "*filter
13159 -A INPUT -p tcp --dport 22 -j ACCEPT
13160 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
13166 @deftp {Data Type} iptables-configuration
13167 The data type representing the configuration of iptables.
13170 @item @code{iptables} (default: @code{iptables})
13171 The iptables package that provides @code{iptables-restore} and
13172 @code{ip6tables-restore}.
13173 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
13174 The iptables rules to use. It will be passed to @code{iptables-restore}.
13175 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13177 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
13178 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
13179 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13185 @defvr {Scheme Variable} nftables-service-type
13186 This is the service type to set up a nftables configuration. nftables is a
13187 netfilter project that aims to replace the existing iptables, ip6tables,
13188 arptables and ebtables framework. It provides a new packet filtering
13189 framework, a new user-space utility @command{nft}, and a compatibility layer
13190 for iptables. This service comes with a default ruleset
13191 @code{%default-nftables-ruleset} that rejecting all incomming connections
13192 except those to the ssh port 22. To use it, simply write:
13195 (service nftables-service-type)
13199 @deftp {Data Type} nftables-configuration
13200 The data type representing the configuration of nftables.
13203 @item @code{package} (default: @code{nftables})
13204 The nftables package that provides @command{nft}.
13205 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
13206 The nftables ruleset to use. This may be any ``file-like'' object
13207 (@pxref{G-Expressions, file-like objects}).
13211 @cindex NTP (Network Time Protocol), service
13212 @cindex ntpd, service for the Network Time Protocol daemon
13213 @cindex real time clock
13214 @defvr {Scheme Variable} ntp-service-type
13215 This is the type of the service running the @uref{http://www.ntp.org,
13216 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
13217 system clock synchronized with that of the specified NTP servers.
13219 The value of this service is an @code{ntpd-configuration} object, as described
13223 @deftp {Data Type} ntp-configuration
13224 This is the data type for the NTP service configuration.
13227 @item @code{servers} (default: @code{%ntp-servers})
13228 This is the list of servers (@code{<ntp-server>} records) with which
13229 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
13232 @item @code{allow-large-adjustment?} (default: @code{#t})
13233 This determines whether @command{ntpd} is allowed to make an initial
13234 adjustment of more than 1,000 seconds.
13236 @item @code{ntp} (default: @code{ntp})
13237 The NTP package to use.
13241 @defvr {Scheme Variable} %ntp-servers
13242 List of host names used as the default NTP servers. These are servers of the
13243 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
13246 @deftp {Data Type} ntp-server
13247 The data type representing the configuration of a NTP server.
13250 @item @code{type} (default: @code{'server})
13251 The type of the NTP server, given as a symbol. One of @code{'pool},
13252 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
13254 @item @code{address}
13255 The address of the server, as a string.
13257 @item @code{options}
13258 NTPD options to use with that specific server, given as a list of option names
13259 and/or of option names and values tuples. The following example define a server
13260 to use with the options @option{iburst} and @option{prefer}, as well as
13261 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
13266 (address "some.ntp.server.org")
13267 (options `(iburst (version 3) (maxpoll 16) prefer))))
13273 @deffn {Scheme Procedure} openntpd-service-type
13274 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
13275 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
13276 clock synchronized with that of the given servers.
13280 openntpd-service-type
13281 (openntpd-configuration
13282 (listen-on '("127.0.0.1" "::1"))
13283 (sensor '("udcf0 correction 70000"))
13284 (constraint-from '("www.gnu.org"))
13285 (constraints-from '("https://www.google.com/"))
13286 (allow-large-adjustment? #t)))
13291 @defvr {Scheme Variable} %openntpd-servers
13292 This variable is a list of the server addresses defined in
13293 @var{%ntp-servers}.
13296 @deftp {Data Type} openntpd-configuration
13298 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
13299 The openntpd executable to use.
13300 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
13301 A list of local IP addresses or hostnames the ntpd daemon should listen on.
13302 @item @code{query-from} (default: @code{'()})
13303 A list of local IP address the ntpd daemon should use for outgoing queries.
13304 @item @code{sensor} (default: @code{'()})
13305 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
13306 will listen to each sensor that actually exists and ignore non-existent ones.
13307 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
13309 @item @code{server} (default: @code{'()})
13310 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
13311 @item @code{servers} (default: @var{%openntp-servers})
13312 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
13313 @item @code{constraint-from} (default: @code{'()})
13314 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
13315 This time information is not used for precision but acts as an authenticated
13316 constraint, thereby reducing the impact of unauthenticated NTP
13317 man-in-the-middle attacks.
13318 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
13320 @item @code{constraints-from} (default: @code{'()})
13321 As with constraint from, specify a list of URLs, IP addresses or hostnames of
13322 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
13323 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
13324 @item @code{allow-large-adjustment?} (default: @code{#f})
13325 Determines if @code{ntpd} is allowed to make an initial adjustment of more
13331 @deffn {Scheme variable} inetd-service-type
13332 This service runs the @command{inetd} (@pxref{inetd invocation,,,
13333 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
13334 connections on internet sockets, and lazily starts the specified server
13335 program when a connection is made on one of these sockets.
13337 The value of this service is an @code{inetd-configuration} object. The
13338 following example configures the @command{inetd} daemon to provide the
13339 built-in @command{echo} service, as well as an smtp service which
13340 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
13341 gateway @code{hostname}:
13346 (inetd-configuration
13350 (socket-type 'stream)
13357 (socket-type 'stream)
13361 (program (file-append openssh "/bin/ssh"))
13363 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13364 "-W" "smtp-server:25" "user@@hostname")))))))
13367 See below for more details about @code{inetd-configuration}.
13370 @deftp {Data Type} inetd-configuration
13371 Data type representing the configuration of @command{inetd}.
13374 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13375 The @command{inetd} executable to use.
13377 @item @code{entries} (default: @code{'()})
13378 A list of @command{inetd} service entries. Each entry should be created
13379 by the @code{inetd-entry} constructor.
13383 @deftp {Data Type} inetd-entry
13384 Data type representing an entry in the @command{inetd} configuration.
13385 Each entry corresponds to a socket where @command{inetd} will listen for
13389 @item @code{node} (default: @code{#f})
13390 Optional string, a comma-separated list of local addresses
13391 @command{inetd} should use when listening for this service.
13392 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13393 description of all options.
13395 A string, the name must correspond to an entry in @code{/etc/services}.
13396 @item @code{socket-type}
13397 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13399 @item @code{protocol}
13400 A string, must correspond to an entry in @code{/etc/protocols}.
13401 @item @code{wait?} (default: @code{#t})
13402 Whether @command{inetd} should wait for the server to exit before
13403 listening to new service requests.
13405 A string containing the user (and, optionally, group) name of the user
13406 as whom the server should run. The group name can be specified in a
13407 suffix, separated by a colon or period, i.e.@: @code{"user"},
13408 @code{"user:group"} or @code{"user.group"}.
13409 @item @code{program} (default: @code{"internal"})
13410 The server program which will serve the requests, or @code{"internal"}
13411 if @command{inetd} should use a built-in service.
13412 @item @code{arguments} (default: @code{'()})
13413 A list strings or file-like objects, which are the server program's
13414 arguments, starting with the zeroth argument, i.e.@: the name of the
13415 program itself. For @command{inetd}'s internal services, this entry
13416 must be @code{'()} or @code{'("internal")}.
13419 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13420 detailed discussion of each configuration field.
13424 @defvr {Scheme Variable} tor-service-type
13425 This is the type for a service that runs the @uref{https://torproject.org,
13426 Tor} anonymous networking daemon. The service is configured using a
13427 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
13428 @code{tor} unprivileged user, which is a member of the @code{tor} group.
13432 @deftp {Data Type} tor-configuration
13434 @item @code{tor} (default: @code{tor})
13435 The package that provides the Tor daemon. This package is expected to provide
13436 the daemon at @file{bin/tor} relative to its output directory. The default
13437 package is the @uref{https://www.torproject.org, Tor Project's}
13440 @item @code{config-file} (default: @code{(plain-file "empty" "")})
13441 The configuration file to use. It will be appended to a default configuration
13442 file, and the final configuration file will be passed to @code{tor} via its
13443 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
13444 file-like objects}). See @code{man tor} for details on the configuration file
13447 @item @code{hidden-services} (default: @code{'()})
13448 The list of @code{<hidden-service>} records to use. For any hidden service
13449 you include in this list, appropriate configuration to enable the hidden
13450 service will be automatically added to the default configuration file. You
13451 may conveniently create @code{<hidden-service>} records using the
13452 @code{tor-hidden-service} procedure described below.
13454 @item @code{socks-socket-type} (default: @code{'tcp})
13455 The default socket type that Tor should use for its SOCKS socket. This must
13456 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
13457 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
13458 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
13459 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13462 If you want to customize the SOCKS socket in more detail, leave
13463 @code{socks-socket-type} at its default value of @code{'tcp} and use
13464 @code{config-file} to override the default by providing your own
13465 @code{SocksPort} option.
13469 @cindex hidden service
13470 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13471 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13472 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13475 '((22 "127.0.0.1:22")
13476 (80 "127.0.0.1:8080"))
13479 In this example, port 22 of the hidden service is mapped to local port 22, and
13480 port 80 is mapped to local port 8080.
13482 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13483 the @file{hostname} file contains the @code{.onion} host name for the hidden
13486 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13487 project's documentation} for more information.
13490 The @code{(gnu services rsync)} module provides the following services:
13492 You might want an rsync daemon if you have files that you want available
13493 so anyone (or just yourself) can download existing files or upload new
13496 @deffn {Scheme Variable} rsync-service-type
13497 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13498 The value for this service type is a
13499 @command{rsync-configuration} record as in this example:
13502 (service rsync-service-type)
13505 See below for details about @code{rsync-configuration}.
13508 @deftp {Data Type} rsync-configuration
13509 Data type representing the configuration for @code{rsync-service}.
13512 @item @code{package} (default: @var{rsync})
13513 @code{rsync} package to use.
13515 @item @code{port-number} (default: @code{873})
13516 TCP port on which @command{rsync} listens for incoming connections. If port
13517 is less than @code{1024} @command{rsync} needs to be started as the
13518 @code{root} user and group.
13520 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
13521 Name of the file where @command{rsync} writes its PID.
13523 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
13524 Name of the file where @command{rsync} writes its lock file.
13526 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
13527 Name of the file where @command{rsync} writes its log file.
13529 @item @code{use-chroot?} (default: @var{#t})
13530 Whether to use chroot for @command{rsync} shared directory.
13532 @item @code{share-path} (default: @file{/srv/rsync})
13533 Location of the @command{rsync} shared directory.
13535 @item @code{share-comment} (default: @code{"Rsync share"})
13536 Comment of the @command{rsync} shared directory.
13538 @item @code{read-only?} (default: @var{#f})
13539 Read-write permissions to shared directory.
13541 @item @code{timeout} (default: @code{300})
13542 I/O timeout in seconds.
13544 @item @code{user} (default: @var{"root"})
13545 Owner of the @code{rsync} process.
13547 @item @code{group} (default: @var{"root"})
13548 Group of the @code{rsync} process.
13550 @item @code{uid} (default: @var{"rsyncd"})
13551 User name or user ID that file transfers to and from that module should take
13552 place as when the daemon was run as @code{root}.
13554 @item @code{gid} (default: @var{"rsyncd"})
13555 Group name or group ID that will be used when accessing the module.
13560 Furthermore, @code{(gnu services ssh)} provides the following services.
13564 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
13565 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
13566 [#:allow-empty-passwords? #f] [#:root-login? #f] @
13567 [#:syslog-output? #t] [#:x11-forwarding? #t] @
13568 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
13569 [#:public-key-authentication? #t] [#:initialize? #t]
13570 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
13571 @var{host-key} must designate a file containing the host key, and readable
13574 When @var{daemonic?} is true, @command{lshd} will detach from the
13575 controlling terminal and log its output to syslogd, unless one sets
13576 @var{syslog-output?} to false. Obviously, it also makes lsh-service
13577 depend on existence of syslogd service. When @var{pid-file?} is true,
13578 @command{lshd} writes its PID to the file called @var{pid-file}.
13580 When @var{initialize?} is true, automatically create the seed and host key
13581 upon service activation if they do not exist yet. This may take long and
13582 require interaction.
13584 When @var{initialize?} is false, it is up to the user to initialize the
13585 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
13586 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
13587 basics,,, lsh, LSH Manual}).
13589 When @var{interfaces} is empty, lshd listens for connections on all the
13590 network interfaces; otherwise, @var{interfaces} must be a list of host names
13593 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
13594 passwords, and @var{root-login?} specifies whether to accept log-ins as
13597 The other options should be self-descriptive.
13602 @deffn {Scheme Variable} openssh-service-type
13603 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
13604 shell daemon, @command{sshd}. Its value must be an
13605 @code{openssh-configuration} record as in this example:
13608 (service openssh-service-type
13609 (openssh-configuration
13610 (x11-forwarding? #t)
13611 (permit-root-login 'without-password)
13613 `(("alice" ,(local-file "alice.pub"))
13614 ("bob" ,(local-file "bob.pub"))))))
13617 See below for details about @code{openssh-configuration}.
13619 This service can be extended with extra authorized keys, as in this
13623 (service-extension openssh-service-type
13624 (const `(("charlie"
13625 ,(local-file "charlie.pub")))))
13629 @deftp {Data Type} openssh-configuration
13630 This is the configuration record for OpenSSH's @command{sshd}.
13633 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
13634 Name of the file where @command{sshd} writes its PID.
13636 @item @code{port-number} (default: @code{22})
13637 TCP port on which @command{sshd} listens for incoming connections.
13639 @item @code{permit-root-login} (default: @code{#f})
13640 This field determines whether and when to allow logins as root. If
13641 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
13642 If it's the symbol @code{'without-password}, then root logins are
13643 permitted but not with password-based authentication.
13645 @item @code{allow-empty-passwords?} (default: @code{#f})
13646 When true, users with empty passwords may log in. When false, they may
13649 @item @code{password-authentication?} (default: @code{#t})
13650 When true, users may log in with their password. When false, they have
13651 other authentication methods.
13653 @item @code{public-key-authentication?} (default: @code{#t})
13654 When true, users may log in using public key authentication. When
13655 false, users have to use other authentication method.
13657 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
13658 This is used only by protocol version 2.
13660 @item @code{x11-forwarding?} (default: @code{#f})
13661 When true, forwarding of X11 graphical client connections is
13662 enabled---in other words, @command{ssh} options @option{-X} and
13663 @option{-Y} will work.
13665 @item @code{allow-agent-forwarding?} (default: @code{#t})
13666 Whether to allow agent forwarding.
13668 @item @code{allow-tcp-forwarding?} (default: @code{#t})
13669 Whether to allow TCP forwarding.
13671 @item @code{gateway-ports?} (default: @code{#f})
13672 Whether to allow gateway ports.
13674 @item @code{challenge-response-authentication?} (default: @code{#f})
13675 Specifies whether challenge response authentication is allowed (e.g.@: via
13678 @item @code{use-pam?} (default: @code{#t})
13679 Enables the Pluggable Authentication Module interface. If set to
13680 @code{#t}, this will enable PAM authentication using
13681 @code{challenge-response-authentication?} and
13682 @code{password-authentication?}, in addition to PAM account and session
13683 module processing for all authentication types.
13685 Because PAM challenge response authentication usually serves an
13686 equivalent role to password authentication, you should disable either
13687 @code{challenge-response-authentication?} or
13688 @code{password-authentication?}.
13690 @item @code{print-last-log?} (default: @code{#t})
13691 Specifies whether @command{sshd} should print the date and time of the
13692 last user login when a user logs in interactively.
13694 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
13695 Configures external subsystems (e.g.@: file transfer daemon).
13697 This is a list of two-element lists, each of which containing the
13698 subsystem name and a command (with optional arguments) to execute upon
13701 The command @command{internal-sftp} implements an in-process SFTP
13702 server. Alternately, one can specify the @command{sftp-server} command:
13704 (service openssh-service-type
13705 (openssh-configuration
13707 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
13710 @item @code{accepted-environment} (default: @code{'()})
13711 List of strings describing which environment variables may be exported.
13713 Each string gets on its own line. See the @code{AcceptEnv} option in
13714 @code{man sshd_config}.
13716 This example allows ssh-clients to export the @code{COLORTERM} variable.
13717 It is set by terminal emulators, which support colors. You can use it in
13718 your shell's ressource file to enable colors for the prompt and commands
13719 if this variable is set.
13722 (service openssh-service-type
13723 (openssh-configuration
13724 (accepted-environment '("COLORTERM"))))
13727 @item @code{authorized-keys} (default: @code{'()})
13728 @cindex authorized keys, SSH
13729 @cindex SSH authorized keys
13730 This is the list of authorized keys. Each element of the list is a user
13731 name followed by one or more file-like objects that represent SSH public
13735 (openssh-configuration
13737 `(("rekado" ,(local-file "rekado.pub"))
13738 ("chris" ,(local-file "chris.pub"))
13739 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
13743 registers the specified public keys for user accounts @code{rekado},
13744 @code{chris}, and @code{root}.
13746 Additional authorized keys can be specified @i{via}
13747 @code{service-extension}.
13749 Note that this does @emph{not} interfere with the use of
13750 @file{~/.ssh/authorized_keys}.
13752 @item @code{log-level} (default: @code{'info})
13753 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
13754 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
13755 page for @file{sshd_config} for the full list of level names.
13757 @item @code{extra-content} (default: @code{""})
13758 This field can be used to append arbitrary text to the configuration file. It
13759 is especially useful for elaborate configurations that cannot be expressed
13760 otherwise. This configuration, for example, would generally disable root
13761 logins, but permit them from one specific IP address:
13764 (openssh-configuration
13766 Match Address 192.168.0.1
13767 PermitRootLogin yes"))
13773 @deffn {Scheme Procedure} dropbear-service [@var{config}]
13774 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
13775 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
13778 For example, to specify a Dropbear service listening on port 1234, add
13779 this call to the operating system's @code{services} field:
13782 (dropbear-service (dropbear-configuration
13783 (port-number 1234)))
13787 @deftp {Data Type} dropbear-configuration
13788 This data type represents the configuration of a Dropbear SSH daemon.
13791 @item @code{dropbear} (default: @var{dropbear})
13792 The Dropbear package to use.
13794 @item @code{port-number} (default: 22)
13795 The TCP port where the daemon waits for incoming connections.
13797 @item @code{syslog-output?} (default: @code{#t})
13798 Whether to enable syslog output.
13800 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
13801 File name of the daemon's PID file.
13803 @item @code{root-login?} (default: @code{#f})
13804 Whether to allow @code{root} logins.
13806 @item @code{allow-empty-passwords?} (default: @code{#f})
13807 Whether to allow empty passwords.
13809 @item @code{password-authentication?} (default: @code{#t})
13810 Whether to enable password-based authentication.
13814 @defvr {Scheme Variable} %facebook-host-aliases
13815 This variable contains a string for use in @file{/etc/hosts}
13816 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
13817 line contains a entry that maps a known server name of the Facebook
13818 on-line service---e.g., @code{www.facebook.com}---to the local
13819 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
13821 This variable is typically used in the @code{hosts-file} field of an
13822 @code{operating-system} declaration (@pxref{operating-system Reference,
13823 @file{/etc/hosts}}):
13826 (use-modules (gnu) (guix))
13829 (host-name "mymachine")
13832 ;; Create a /etc/hosts file with aliases for "localhost"
13833 ;; and "mymachine", as well as for Facebook servers.
13834 (plain-file "hosts"
13835 (string-append (local-host-aliases host-name)
13836 %facebook-host-aliases))))
13839 This mechanism can prevent programs running locally, such as Web
13840 browsers, from accessing Facebook.
13843 The @code{(gnu services avahi)} provides the following definition.
13845 @defvr {Scheme Variable} avahi-service-type
13846 This is the service that runs @command{avahi-daemon}, a system-wide
13847 mDNS/DNS-SD responder that allows for service discovery and
13848 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
13849 Its value must be a @code{zero-configuration} record---see below.
13851 This service extends the name service cache daemon (nscd) so that it can
13852 resolve @code{.local} host names using
13853 @uref{http://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
13854 Service Switch}, for information on host name resolution.
13856 Additionally, add the @var{avahi} package to the system profile so that
13857 commands such as @command{avahi-browse} are directly usable.
13860 @deftp {Data Type} avahi-configuration
13861 Data type representation the configuration for Avahi.
13865 @item @code{host-name} (default: @code{#f})
13866 If different from @code{#f}, use that as the host name to
13867 publish for this machine; otherwise, use the machine's actual host name.
13869 @item @code{publish?} (default: @code{#t})
13870 When true, allow host names and services to be published (broadcast) over the
13873 @item @code{publish-workstation?} (default: @code{#t})
13874 When true, @command{avahi-daemon} publishes the machine's host name and IP
13875 address via mDNS on the local network. To view the host names published on
13876 your local network, you can run:
13879 avahi-browse _workstation._tcp
13882 @item @code{wide-area?} (default: @code{#f})
13883 When true, DNS-SD over unicast DNS is enabled.
13885 @item @code{ipv4?} (default: @code{#t})
13886 @itemx @code{ipv6?} (default: @code{#t})
13887 These fields determine whether to use IPv4/IPv6 sockets.
13889 @item @code{domains-to-browse} (default: @code{'()})
13890 This is a list of domains to browse.
13894 @deffn {Scheme Variable} openvswitch-service-type
13895 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
13896 service, whose value should be an @code{openvswitch-configuration}
13900 @deftp {Data Type} openvswitch-configuration
13901 Data type representing the configuration of Open vSwitch, a multilayer
13902 virtual switch which is designed to enable massive network automation
13903 through programmatic extension.
13906 @item @code{package} (default: @var{openvswitch})
13907 Package object of the Open vSwitch.
13913 @subsection X Window
13916 @cindex X Window System
13917 @cindex login manager
13918 Support for the X Window graphical display system---specifically
13919 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
13920 there is no @code{xorg-service} procedure. Instead, the X server is
13921 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
13924 @cindex GNOME, login manager
13925 GDM of course allows users to log in into window managers and desktop
13926 environments other than GNOME; for those using GNOME, GDM is required for
13927 features such as automatic screen locking.
13929 @cindex window manager
13930 To use X11, you must install at least one @dfn{window manager}---for
13931 example the @code{windowmaker} or @code{openbox} packages---preferably
13932 by adding it to the @code{packages} field of your operating system
13933 definition (@pxref{operating-system Reference, system-wide packages}).
13935 @defvr {Scheme Variable} gdm-service-type
13936 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
13937 Desktop Manager} (GDM), a program that manages graphical display servers and
13938 handles graphical user logins. Its value must be a @code{gdm-configuration}
13941 @cindex session types (X11)
13942 @cindex X11 session types
13943 GDM looks for @dfn{session types} described by the @file{.desktop} files in
13944 @file{/run/current-system/profile/share/xsessions} and allows users to choose
13945 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
13946 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
13947 set of packages automatically makes them available at the log-in screen.
13949 In addition, @file{~/.xsession} files are honored. When available,
13950 @file{~/.xsession} must be an executable that starts a window manager
13951 and/or other X clients.
13954 @deftp {Data Type} gdm-configuration
13956 @item @code{auto-login?} (default: @code{#f})
13957 @itemx @code{default-user} (default: @code{#f})
13958 When @code{auto-login?} is false, GDM presents a log-in screen.
13960 When @code{auto-login?} is true, GDM logs in directly as
13961 @code{default-user}.
13963 @item @code{gnome-shell-assets} (default: ...)
13964 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
13966 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
13967 Configuration of the Xorg graphical server.
13969 @item @code{xsession} (default: @code{(xinitrc)})
13970 Script to run before starting a X session.
13972 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
13973 File name of the @code{dbus-daemon} executable.
13975 @item @code{gdm} (default: @code{gdm})
13976 The GDM package to use.
13980 @defvr {Scheme Variable} slim-service-type
13981 This is the type for the SLiM graphical login manager for X11.
13983 Like GDM, SLiM looks for session types described by @file{.desktop} files and
13984 allows users to choose a session from the log-in screen using @kbd{F1}. It
13985 also honors @file{~/.xsession} files.
13987 Unlike GDM, SLiM does not spawn the user session on a different VT after
13988 logging in, which means that you can only start one graphical session. If you
13989 want to be able to run multiple graphical sessions at the same time you have
13990 to add multiple SLiM services to your system services. The following example
13991 shows how to replace the default GDM service with two SLiM services on tty7
13995 (use-modules (gnu services)
13996 (gnu services desktop)
13997 (gnu services xorg)
13998 (srfi srfi-1)) ;for 'remove'
14002 (services (cons* (service slim-service-type (slim-configuration
14005 (service slim-service-type (slim-configuration
14008 (remove (lambda (service)
14009 (eq? (service-kind service) gdm-service-type))
14010 %desktop-services))))
14015 @deftp {Data Type} slim-configuration
14016 Data type representing the configuration of @code{slim-service-type}.
14019 @item @code{allow-empty-passwords?} (default: @code{#t})
14020 Whether to allow logins with empty passwords.
14022 @item @code{auto-login?} (default: @code{#f})
14023 @itemx @code{default-user} (default: @code{""})
14024 When @code{auto-login?} is false, SLiM presents a log-in screen.
14026 When @code{auto-login?} is true, SLiM logs in directly as
14027 @code{default-user}.
14029 @item @code{theme} (default: @code{%default-slim-theme})
14030 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
14031 The graphical theme to use and its name.
14033 @item @code{auto-login-session} (default: @code{#f})
14034 If true, this must be the name of the executable to start as the default
14035 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
14037 If false, a session described by one of the available @file{.desktop}
14038 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
14042 You must install at least one window manager in the system profile or in
14043 your user profile. Failing to do that, if @code{auto-login-session} is
14044 false, you will be unable to log in.
14047 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14048 Configuration of the Xorg graphical server.
14050 @item @code{display} (default @code{":0"})
14051 The display on which to start the Xorg graphical server.
14053 @item @code{vt} (default @code{"vt7"})
14054 The VT on which to start the Xorg graphical server.
14056 @item @code{xauth} (default: @code{xauth})
14057 The XAuth package to use.
14059 @item @code{shepherd} (default: @code{shepherd})
14060 The Shepherd package used when invoking @command{halt} and
14063 @item @code{sessreg} (default: @code{sessreg})
14064 The sessreg package used in order to register the session.
14066 @item @code{slim} (default: @code{slim})
14067 The SLiM package to use.
14071 @defvr {Scheme Variable} %default-theme
14072 @defvrx {Scheme Variable} %default-theme-name
14073 The default SLiM theme and its name.
14077 @deftp {Data Type} sddm-configuration
14078 This is the data type representing the sddm service configuration.
14081 @item @code{display-server} (default: "x11")
14082 Select display server to use for the greeter. Valid values are "x11"
14085 @item @code{numlock} (default: "on")
14086 Valid values are "on", "off" or "none".
14088 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
14089 Command to run when halting.
14091 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
14092 Command to run when rebooting.
14094 @item @code{theme} (default "maldives")
14095 Theme to use. Default themes provided by SDDM are "elarun" or "maldives".
14097 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
14098 Directory to look for themes.
14100 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
14101 Directory to look for faces.
14103 @item @code{default-path} (default "/run/current-system/profile/bin")
14104 Default PATH to use.
14106 @item @code{minimum-uid} (default: 1000)
14107 Minimum UID displayed in SDDM and allowed for log-in.
14109 @item @code{maximum-uid} (default: 2000)
14110 Maximum UID to display in SDDM.
14112 @item @code{remember-last-user?} (default #t)
14113 Remember last user.
14115 @item @code{remember-last-session?} (default #t)
14116 Remember last session.
14118 @item @code{hide-users} (default "")
14119 Usernames to hide from SDDM greeter.
14121 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
14122 Users with shells listed will be hidden from the SDDM greeter.
14124 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
14125 Script to run before starting a wayland session.
14127 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
14128 Directory to look for desktop files starting wayland sessions.
14130 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14131 Configuration of the Xorg graphical server.
14133 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
14136 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
14139 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
14140 Script to run after starting xorg-server.
14142 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
14143 Script to run before stopping xorg-server.
14145 @item @code{xsession-command} (default: @code{xinitrc})
14146 Script to run before starting a X session.
14148 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
14149 Directory to look for desktop files starting X sessions.
14151 @item @code{minimum-vt} (default: 7)
14154 @item @code{auto-login-user} (default "")
14155 User to use for auto-login.
14157 @item @code{auto-login-session} (default "")
14158 Desktop file to use for auto-login.
14160 @item @code{relogin?} (default #f)
14161 Relogin after logout.
14166 @cindex login manager
14168 @deffn {Scheme Procedure} sddm-service config
14169 Return a service that spawns the SDDM graphical login manager for config of
14170 type @code{<sddm-configuration>}.
14173 (sddm-service (sddm-configuration
14174 (auto-login-user "Alice")
14175 (auto-login-session "xfce.desktop")))
14179 @cindex Xorg, configuration
14180 @deftp {Data Type} xorg-configuration
14181 This data type represents the configuration of the Xorg graphical display
14182 server. Note that there is not Xorg service; instead, the X server is started
14183 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
14184 of these display managers aggregates an @code{xorg-configuration} record.
14187 @item @code{modules} (default: @code{%default-xorg-modules})
14188 This is a list of @dfn{module packages} loaded by the Xorg
14189 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
14191 @item @code{fonts} (default: @code{%default-xorg-fonts})
14192 This is a list of font directories to add to the server's @dfn{font path}.
14194 @item @code{drivers} (default: @code{'()})
14195 This must be either the empty list, in which case Xorg chooses a graphics
14196 driver automatically, or a list of driver names that will be tried in this
14197 order---e.g., @code{("modesetting" "vesa")}.
14199 @item @code{resolutions} (default: @code{'()})
14200 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
14201 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
14204 @cindex keyboard layout, for Xorg
14205 @cindex keymap, for Xorg
14206 @item @code{keyboard-layout} (default: @code{#f})
14207 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
14208 English (``qwerty'') for a 105-key PC keyboard.
14210 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
14211 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
14212 information on how to specify the keyboard layout.
14214 @item @code{extra-config} (default: @code{'()})
14215 This is a list of strings or objects appended to the configuration file. It
14216 is used to pass extra text to be added verbatim to the configuration file.
14218 @item @code{server} (default: @code{xorg-server})
14219 This is the package providing the Xorg server.
14221 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
14222 This is the list of command-line arguments to pass to the X server. The
14223 default is @code{-nolisten tcp}.
14227 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
14228 [@var{login-manager-service-type}]
14229 Tell the log-in manager (of type @var{login-manager-service-type}) to use
14230 @var{config}, an @code{<xorg-configuration>} record.
14232 Since the Xorg configuration is embedded in the log-in manager's
14233 configuration---e.g., @code{gdm-configuration}---this procedure provides a
14234 shorthand to set the Xorg configuration.
14237 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
14238 Return a @code{startx} script in which the modules, fonts, etc. specified
14239 in @var{config}, are available. The result should be used in place of
14242 Usually the X server is started by a login manager.
14246 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
14247 Add @var{package}, a package for a screen locker or screen saver whose
14248 command is @var{program}, to the set of setuid programs and add a PAM entry
14249 for it. For example:
14252 (screen-locker-service xlockmore "xlock")
14255 makes the good ol' XlockMore usable.
14259 @node Printing Services
14260 @subsection Printing Services
14262 @cindex printer support with CUPS
14263 The @code{(gnu services cups)} module provides a Guix service definition
14264 for the CUPS printing service. To add printer support to a Guix
14265 system, add a @code{cups-service} to the operating system definition:
14267 @deffn {Scheme Variable} cups-service-type
14268 The service type for the CUPS print server. Its value should be a valid
14269 CUPS configuration (see below). To use the default settings, simply
14272 (service cups-service-type)
14276 The CUPS configuration controls the basic things about your CUPS
14277 installation: what interfaces it listens on, what to do if a print job
14278 fails, how much logging to do, and so on. To actually add a printer,
14279 you have to visit the @url{http://localhost:631} URL, or use a tool such
14280 as GNOME's printer configuration services. By default, configuring a
14281 CUPS service will generate a self-signed certificate if needed, for
14282 secure connections to the print server.
14284 Suppose you want to enable the Web interface of CUPS and also add
14285 support for Epson printers @i{via} the @code{escpr} package and for HP
14286 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
14287 like this (you need to use the @code{(gnu packages cups)} module):
14290 (service cups-service-type
14291 (cups-configuration
14292 (web-interface? #t)
14294 (list cups-filters escpr hplip-minimal))))
14297 Note: If you wish to use the Qt5 based GUI which comes with the hplip
14298 package then it is suggested that you install the @code{hplip} package,
14299 either in your OS configuration file or as your user.
14301 The available configuration parameters follow. Each parameter
14302 definition is preceded by its type; for example, @samp{string-list foo}
14303 indicates that the @code{foo} parameter should be specified as a list of
14304 strings. There is also a way to specify the configuration as a string,
14305 if you have an old @code{cupsd.conf} file that you want to port over
14306 from some other system; see the end for more details.
14308 @c The following documentation was initially generated by
14309 @c (generate-documentation) in (gnu services cups). Manually maintained
14310 @c documentation is better, so we shouldn't hesitate to edit below as
14311 @c needed. However if the change you want to make to this documentation
14312 @c can be done in an automated way, it's probably easier to change
14313 @c (generate-documentation) than to make it below and have to deal with
14314 @c the churn as CUPS updates.
14317 Available @code{cups-configuration} fields are:
14319 @deftypevr {@code{cups-configuration} parameter} package cups
14323 @deftypevr {@code{cups-configuration} parameter} package-list extensions
14324 Drivers and other extensions to the CUPS package.
14327 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
14328 Configuration of where to write logs, what directories to use for print
14329 spools, and related privileged configuration parameters.
14331 Available @code{files-configuration} fields are:
14333 @deftypevr {@code{files-configuration} parameter} log-location access-log
14334 Defines the access log filename. Specifying a blank filename disables
14335 access log generation. The value @code{stderr} causes log entries to be
14336 sent to the standard error file when the scheduler is running in the
14337 foreground, or to the system log daemon when run in the background. The
14338 value @code{syslog} causes log entries to be sent to the system log
14339 daemon. The server name may be included in filenames using the string
14340 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
14342 Defaults to @samp{"/var/log/cups/access_log"}.
14345 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
14346 Where CUPS should cache data.
14348 Defaults to @samp{"/var/cache/cups"}.
14351 @deftypevr {@code{files-configuration} parameter} string config-file-perm
14352 Specifies the permissions for all configuration files that the scheduler
14355 Note that the permissions for the printers.conf file are currently
14356 masked to only allow access from the scheduler user (typically root).
14357 This is done because printer device URIs sometimes contain sensitive
14358 authentication information that should not be generally known on the
14359 system. There is no way to disable this security feature.
14361 Defaults to @samp{"0640"}.
14364 @deftypevr {@code{files-configuration} parameter} log-location error-log
14365 Defines the error log filename. Specifying a blank filename disables
14366 error log generation. The value @code{stderr} causes log entries to be
14367 sent to the standard error file when the scheduler is running in the
14368 foreground, or to the system log daemon when run in the background. The
14369 value @code{syslog} causes log entries to be sent to the system log
14370 daemon. The server name may be included in filenames using the string
14371 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
14373 Defaults to @samp{"/var/log/cups/error_log"}.
14376 @deftypevr {@code{files-configuration} parameter} string fatal-errors
14377 Specifies which errors are fatal, causing the scheduler to exit. The
14382 No errors are fatal.
14385 All of the errors below are fatal.
14388 Browsing initialization errors are fatal, for example failed connections
14389 to the DNS-SD daemon.
14392 Configuration file syntax errors are fatal.
14395 Listen or Port errors are fatal, except for IPv6 failures on the
14396 loopback or @code{any} addresses.
14399 Log file creation or write errors are fatal.
14402 Bad startup file permissions are fatal, for example shared TLS
14403 certificate and key files with world-read permissions.
14406 Defaults to @samp{"all -browse"}.
14409 @deftypevr {@code{files-configuration} parameter} boolean file-device?
14410 Specifies whether the file pseudo-device can be used for new printer
14411 queues. The URI @uref{file:///dev/null} is always allowed.
14413 Defaults to @samp{#f}.
14416 @deftypevr {@code{files-configuration} parameter} string group
14417 Specifies the group name or ID that will be used when executing external
14420 Defaults to @samp{"lp"}.
14423 @deftypevr {@code{files-configuration} parameter} string log-file-perm
14424 Specifies the permissions for all log files that the scheduler writes.
14426 Defaults to @samp{"0644"}.
14429 @deftypevr {@code{files-configuration} parameter} log-location page-log
14430 Defines the page log filename. Specifying a blank filename disables
14431 page log generation. The value @code{stderr} causes log entries to be
14432 sent to the standard error file when the scheduler is running in the
14433 foreground, or to the system log daemon when run in the background. The
14434 value @code{syslog} causes log entries to be sent to the system log
14435 daemon. The server name may be included in filenames using the string
14436 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
14438 Defaults to @samp{"/var/log/cups/page_log"}.
14441 @deftypevr {@code{files-configuration} parameter} string remote-root
14442 Specifies the username that is associated with unauthenticated accesses
14443 by clients claiming to be the root user. The default is @code{remroot}.
14445 Defaults to @samp{"remroot"}.
14448 @deftypevr {@code{files-configuration} parameter} file-name request-root
14449 Specifies the directory that contains print jobs and other HTTP request
14452 Defaults to @samp{"/var/spool/cups"}.
14455 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
14456 Specifies the level of security sandboxing that is applied to print
14457 filters, backends, and other child processes of the scheduler; either
14458 @code{relaxed} or @code{strict}. This directive is currently only
14459 used/supported on macOS.
14461 Defaults to @samp{strict}.
14464 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
14465 Specifies the location of TLS certificates and private keys. CUPS will
14466 look for public and private keys in this directory: a @code{.crt} files
14467 for PEM-encoded certificates and corresponding @code{.key} files for
14468 PEM-encoded private keys.
14470 Defaults to @samp{"/etc/cups/ssl"}.
14473 @deftypevr {@code{files-configuration} parameter} file-name server-root
14474 Specifies the directory containing the server configuration files.
14476 Defaults to @samp{"/etc/cups"}.
14479 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
14480 Specifies whether the scheduler calls fsync(2) after writing
14481 configuration or state files.
14483 Defaults to @samp{#f}.
14486 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
14487 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
14490 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
14491 Specifies the directory where temporary files are stored.
14493 Defaults to @samp{"/var/spool/cups/tmp"}.
14496 @deftypevr {@code{files-configuration} parameter} string user
14497 Specifies the user name or ID that is used when running external
14500 Defaults to @samp{"lp"}.
14503 @deftypevr {@code{files-configuration} parameter} string set-env
14504 Set the specified environment variable to be passed to child processes.
14506 Defaults to @samp{"variable value"}.
14510 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
14511 Specifies the logging level for the AccessLog file. The @code{config}
14512 level logs when printers and classes are added, deleted, or modified and
14513 when configuration files are accessed or updated. The @code{actions}
14514 level logs when print jobs are submitted, held, released, modified, or
14515 canceled, and any of the conditions for @code{config}. The @code{all}
14516 level logs all requests.
14518 Defaults to @samp{actions}.
14521 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
14522 Specifies whether to purge job history data automatically when it is no
14523 longer required for quotas.
14525 Defaults to @samp{#f}.
14528 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
14529 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
14530 For example, @samp{"_cups" "_print"} will tell network clients that both
14531 CUPS sharing and IPP Everywhere are supported.
14533 Defaults to @samp{"_cups"}.
14536 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
14537 Specifies which protocols to use for local printer sharing.
14539 Defaults to @samp{dnssd}.
14542 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
14543 Specifies whether the CUPS web interface is advertised.
14545 Defaults to @samp{#f}.
14548 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
14549 Specifies whether shared printers are advertised.
14551 Defaults to @samp{#f}.
14554 @deftypevr {@code{cups-configuration} parameter} string classification
14555 Specifies the security classification of the server. Any valid banner
14556 name can be used, including "classified", "confidential", "secret",
14557 "topsecret", and "unclassified", or the banner can be omitted to disable
14558 secure printing functions.
14560 Defaults to @samp{""}.
14563 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
14564 Specifies whether users may override the classification (cover page) of
14565 individual print jobs using the @code{job-sheets} option.
14567 Defaults to @samp{#f}.
14570 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
14571 Specifies the default type of authentication to use.
14573 Defaults to @samp{Basic}.
14576 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
14577 Specifies whether encryption will be used for authenticated requests.
14579 Defaults to @samp{Required}.
14582 @deftypevr {@code{cups-configuration} parameter} string default-language
14583 Specifies the default language to use for text and web content.
14585 Defaults to @samp{"en"}.
14588 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
14589 Specifies the default paper size for new print queues. @samp{"Auto"}
14590 uses a locale-specific default, while @samp{"None"} specifies there is
14591 no default paper size. Specific size names are typically
14592 @samp{"Letter"} or @samp{"A4"}.
14594 Defaults to @samp{"Auto"}.
14597 @deftypevr {@code{cups-configuration} parameter} string default-policy
14598 Specifies the default access policy to use.
14600 Defaults to @samp{"default"}.
14603 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
14604 Specifies whether local printers are shared by default.
14606 Defaults to @samp{#t}.
14609 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
14610 Specifies the delay for updating of configuration and state files, in
14611 seconds. A value of 0 causes the update to happen as soon as possible,
14612 typically within a few milliseconds.
14614 Defaults to @samp{30}.
14617 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
14618 Specifies what to do when an error occurs. Possible values are
14619 @code{abort-job}, which will discard the failed print job;
14620 @code{retry-job}, which will retry the job at a later time;
14621 @code{retry-current-job}, which retries the failed job immediately; and
14622 @code{stop-printer}, which stops the printer.
14624 Defaults to @samp{stop-printer}.
14627 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
14628 Specifies the maximum cost of filters that are run concurrently, which
14629 can be used to minimize disk, memory, and CPU resource problems. A
14630 limit of 0 disables filter limiting. An average print to a
14631 non-PostScript printer needs a filter limit of about 200. A PostScript
14632 printer needs about half that (100). Setting the limit below these
14633 thresholds will effectively limit the scheduler to printing a single job
14636 Defaults to @samp{0}.
14639 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
14640 Specifies the scheduling priority of filters that are run to print a
14641 job. The nice value ranges from 0, the highest priority, to 19, the
14644 Defaults to @samp{0}.
14647 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
14648 Specifies whether to do reverse lookups on connecting clients. The
14649 @code{double} setting causes @code{cupsd} to verify that the hostname
14650 resolved from the address matches one of the addresses returned for that
14651 hostname. Double lookups also prevent clients with unregistered
14652 addresses from connecting to your server. Only set this option to
14653 @code{#t} or @code{double} if absolutely required.
14655 Defaults to @samp{#f}.
14658 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
14659 Specifies the number of seconds to wait before killing the filters and
14660 backend associated with a canceled or held job.
14662 Defaults to @samp{30}.
14665 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
14666 Specifies the interval between retries of jobs in seconds. This is
14667 typically used for fax queues but can also be used with normal print
14668 queues whose error policy is @code{retry-job} or
14669 @code{retry-current-job}.
14671 Defaults to @samp{30}.
14674 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
14675 Specifies the number of retries that are done for jobs. This is
14676 typically used for fax queues but can also be used with normal print
14677 queues whose error policy is @code{retry-job} or
14678 @code{retry-current-job}.
14680 Defaults to @samp{5}.
14683 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
14684 Specifies whether to support HTTP keep-alive connections.
14686 Defaults to @samp{#t}.
14689 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
14690 Specifies how long an idle client connection remains open, in seconds.
14692 Defaults to @samp{30}.
14695 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
14696 Specifies the maximum size of print files, IPP requests, and HTML form
14697 data. A limit of 0 disables the limit check.
14699 Defaults to @samp{0}.
14702 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
14703 Listens on the specified interfaces for connections. Valid values are
14704 of the form @var{address}:@var{port}, where @var{address} is either an
14705 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
14706 indicate all addresses. Values can also be file names of local UNIX
14707 domain sockets. The Listen directive is similar to the Port directive
14708 but allows you to restrict access to specific interfaces or networks.
14711 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
14712 Specifies the number of pending connections that will be allowed. This
14713 normally only affects very busy servers that have reached the MaxClients
14714 limit, but can also be triggered by large numbers of simultaneous
14715 connections. When the limit is reached, the operating system will
14716 refuse additional connections until the scheduler can accept the pending
14719 Defaults to @samp{128}.
14722 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
14723 Specifies a set of additional access controls.
14725 Available @code{location-access-controls} fields are:
14727 @deftypevr {@code{location-access-controls} parameter} file-name path
14728 Specifies the URI path to which the access control applies.
14731 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
14732 Access controls for all access to this path, in the same format as the
14733 @code{access-controls} of @code{operation-access-control}.
14735 Defaults to @samp{()}.
14738 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
14739 Access controls for method-specific access to this path.
14741 Defaults to @samp{()}.
14743 Available @code{method-access-controls} fields are:
14745 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
14746 If @code{#t}, apply access controls to all methods except the listed
14747 methods. Otherwise apply to only the listed methods.
14749 Defaults to @samp{#f}.
14752 @deftypevr {@code{method-access-controls} parameter} method-list methods
14753 Methods to which this access control applies.
14755 Defaults to @samp{()}.
14758 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
14759 Access control directives, as a list of strings. Each string should be
14760 one directive, such as "Order allow,deny".
14762 Defaults to @samp{()}.
14767 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
14768 Specifies the number of debugging messages that are retained for logging
14769 if an error occurs in a print job. Debug messages are logged regardless
14770 of the LogLevel setting.
14772 Defaults to @samp{100}.
14775 @deftypevr {@code{cups-configuration} parameter} log-level log-level
14776 Specifies the level of logging for the ErrorLog file. The value
14777 @code{none} stops all logging while @code{debug2} logs everything.
14779 Defaults to @samp{info}.
14782 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
14783 Specifies the format of the date and time in the log files. The value
14784 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
14786 Defaults to @samp{standard}.
14789 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
14790 Specifies the maximum number of simultaneous clients that are allowed by
14793 Defaults to @samp{100}.
14796 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
14797 Specifies the maximum number of simultaneous clients that are allowed
14798 from a single address.
14800 Defaults to @samp{100}.
14803 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
14804 Specifies the maximum number of copies that a user can print of each
14807 Defaults to @samp{9999}.
14810 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
14811 Specifies the maximum time a job may remain in the @code{indefinite}
14812 hold state before it is canceled. A value of 0 disables cancellation of
14815 Defaults to @samp{0}.
14818 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
14819 Specifies the maximum number of simultaneous jobs that are allowed. Set
14820 to 0 to allow an unlimited number of jobs.
14822 Defaults to @samp{500}.
14825 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
14826 Specifies the maximum number of simultaneous jobs that are allowed per
14827 printer. A value of 0 allows up to MaxJobs jobs per printer.
14829 Defaults to @samp{0}.
14832 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
14833 Specifies the maximum number of simultaneous jobs that are allowed per
14834 user. A value of 0 allows up to MaxJobs jobs per user.
14836 Defaults to @samp{0}.
14839 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
14840 Specifies the maximum time a job may take to print before it is
14841 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
14843 Defaults to @samp{10800}.
14846 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
14847 Specifies the maximum size of the log files before they are rotated, in
14848 bytes. The value 0 disables log rotation.
14850 Defaults to @samp{1048576}.
14853 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
14854 Specifies the maximum amount of time to allow between files in a
14855 multiple file print job, in seconds.
14857 Defaults to @samp{300}.
14860 @deftypevr {@code{cups-configuration} parameter} string page-log-format
14861 Specifies the format of PageLog lines. Sequences beginning with percent
14862 (@samp{%}) characters are replaced with the corresponding information,
14863 while all other characters are copied literally. The following percent
14864 sequences are recognized:
14868 insert a single percent character
14871 insert the value of the specified IPP attribute
14874 insert the number of copies for the current page
14877 insert the current page number
14880 insert the current date and time in common log format
14886 insert the printer name
14889 insert the username
14892 A value of the empty string disables page logging. The string @code{%p
14893 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
14894 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
14897 Defaults to @samp{""}.
14900 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
14901 Passes the specified environment variable(s) to child processes; a list
14904 Defaults to @samp{()}.
14907 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
14908 Specifies named access control policies.
14910 Available @code{policy-configuration} fields are:
14912 @deftypevr {@code{policy-configuration} parameter} string name
14913 Name of the policy.
14916 @deftypevr {@code{policy-configuration} parameter} string job-private-access
14917 Specifies an access list for a job's private values. @code{@@ACL} maps
14918 to the printer's requesting-user-name-allowed or
14919 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14920 owner. @code{@@SYSTEM} maps to the groups listed for the
14921 @code{system-group} field of the @code{files-config} configuration,
14922 which is reified into the @code{cups-files.conf(5)} file. Other
14923 possible elements of the access list include specific user names, and
14924 @code{@@@var{group}} to indicate members of a specific group. The
14925 access list may also be simply @code{all} or @code{default}.
14927 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14930 @deftypevr {@code{policy-configuration} parameter} string job-private-values
14931 Specifies the list of job values to make private, or @code{all},
14932 @code{default}, or @code{none}.
14934 Defaults to @samp{"job-name job-originating-host-name
14935 job-originating-user-name phone"}.
14938 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
14939 Specifies an access list for a subscription's private values.
14940 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
14941 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14942 owner. @code{@@SYSTEM} maps to the groups listed for the
14943 @code{system-group} field of the @code{files-config} configuration,
14944 which is reified into the @code{cups-files.conf(5)} file. Other
14945 possible elements of the access list include specific user names, and
14946 @code{@@@var{group}} to indicate members of a specific group. The
14947 access list may also be simply @code{all} or @code{default}.
14949 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14952 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
14953 Specifies the list of job values to make private, or @code{all},
14954 @code{default}, or @code{none}.
14956 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
14957 notify-subscriber-user-name notify-user-data"}.
14960 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
14961 Access control by IPP operation.
14963 Defaults to @samp{()}.
14967 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
14968 Specifies whether job files (documents) are preserved after a job is
14969 printed. If a numeric value is specified, job files are preserved for
14970 the indicated number of seconds after printing. Otherwise a boolean
14971 value applies indefinitely.
14973 Defaults to @samp{86400}.
14976 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
14977 Specifies whether the job history is preserved after a job is printed.
14978 If a numeric value is specified, the job history is preserved for the
14979 indicated number of seconds after printing. If @code{#t}, the job
14980 history is preserved until the MaxJobs limit is reached.
14982 Defaults to @samp{#t}.
14985 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
14986 Specifies the amount of time to wait for job completion before
14987 restarting the scheduler.
14989 Defaults to @samp{30}.
14992 @deftypevr {@code{cups-configuration} parameter} string rip-cache
14993 Specifies the maximum amount of memory to use when converting documents
14994 into bitmaps for a printer.
14996 Defaults to @samp{"128m"}.
14999 @deftypevr {@code{cups-configuration} parameter} string server-admin
15000 Specifies the email address of the server administrator.
15002 Defaults to @samp{"root@@localhost.localdomain"}.
15005 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
15006 The ServerAlias directive is used for HTTP Host header validation when
15007 clients connect to the scheduler from external interfaces. Using the
15008 special name @code{*} can expose your system to known browser-based DNS
15009 rebinding attacks, even when accessing sites through a firewall. If the
15010 auto-discovery of alternate names does not work, we recommend listing
15011 each alternate name with a ServerAlias directive instead of using
15014 Defaults to @samp{*}.
15017 @deftypevr {@code{cups-configuration} parameter} string server-name
15018 Specifies the fully-qualified host name of the server.
15020 Defaults to @samp{"localhost"}.
15023 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
15024 Specifies what information is included in the Server header of HTTP
15025 responses. @code{None} disables the Server header. @code{ProductOnly}
15026 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
15027 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
15028 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
15029 the output of the @code{uname} command. @code{Full} reports @code{CUPS
15030 2.0.0 (@var{uname}) IPP/2.0}.
15032 Defaults to @samp{Minimal}.
15035 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
15036 Listens on the specified interfaces for encrypted connections. Valid
15037 values are of the form @var{address}:@var{port}, where @var{address} is
15038 either an IPv6 address enclosed in brackets, an IPv4 address, or
15039 @code{*} to indicate all addresses.
15041 Defaults to @samp{()}.
15044 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
15045 Sets encryption options. By default, CUPS only supports encryption
15046 using TLS v1.0 or higher using known secure cipher suites. Security is
15047 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
15048 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
15049 suites, which are required for some older clients. The @code{AllowSSL3} option
15050 enables SSL v3.0, which is required for some older clients that do not support
15051 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
15052 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
15053 protocol version to TLS v1.1.
15055 Defaults to @samp{()}.
15058 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
15059 Specifies whether the scheduler requires clients to strictly adhere to
15060 the IPP specifications.
15062 Defaults to @samp{#f}.
15065 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
15066 Specifies the HTTP request timeout, in seconds.
15068 Defaults to @samp{300}.
15072 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
15073 Specifies whether the web interface is enabled.
15075 Defaults to @samp{#f}.
15078 At this point you're probably thinking ``oh dear, Guix manual, I like
15079 you but you can stop already with the configuration options''. Indeed.
15080 However, one more point: it could be that you have an existing
15081 @code{cupsd.conf} that you want to use. In that case, you can pass an
15082 @code{opaque-cups-configuration} as the configuration of a
15083 @code{cups-service-type}.
15085 Available @code{opaque-cups-configuration} fields are:
15087 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
15091 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
15092 The contents of the @code{cupsd.conf}, as a string.
15095 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
15096 The contents of the @code{cups-files.conf} file, as a string.
15099 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
15100 strings of the same name, you could instantiate a CUPS service like
15104 (service cups-service-type
15105 (opaque-cups-configuration
15106 (cupsd.conf cupsd.conf)
15107 (cups-files.conf cups-files.conf)))
15111 @node Desktop Services
15112 @subsection Desktop Services
15114 The @code{(gnu services desktop)} module provides services that are
15115 usually useful in the context of a ``desktop'' setup---that is, on a
15116 machine running a graphical display server, possibly with graphical user
15117 interfaces, etc. It also defines services that provide specific desktop
15118 environments like GNOME, Xfce or MATE.
15120 To simplify things, the module defines a variable containing the set of
15121 services that users typically expect on a machine with a graphical
15122 environment and networking:
15124 @defvr {Scheme Variable} %desktop-services
15125 This is a list of services that builds upon @code{%base-services} and
15126 adds or adjusts services for a typical ``desktop'' setup.
15128 In particular, it adds a graphical login manager (@pxref{X Window,
15129 @code{gdm-service-type}}), screen lockers, a network management tool
15130 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
15131 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
15132 energy and color management services, the @code{elogind} login and seat
15133 manager, the Polkit privilege service, the GeoClue location service, the
15134 AccountsService daemon that allows authorized users change system passwords,
15135 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
15136 name service switch service configured to be able to use @code{nss-mdns}
15137 (@pxref{Name Service Switch, mDNS}).
15140 The @code{%desktop-services} variable can be used as the @code{services}
15141 field of an @code{operating-system} declaration (@pxref{operating-system
15142 Reference, @code{services}}).
15144 Additionally, the @code{gnome-desktop-service-type},
15145 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
15146 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
15147 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
15148 services like the backlight adjustment helpers and the power management
15149 utilities are added to the system, extending @code{polkit} and @code{dbus}
15150 appropriately, allowing GNOME to operate with elevated privileges on a
15151 limited number of special-purpose system interfaces. Additionally,
15152 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
15153 metapackage to the system profile. Likewise, adding the Xfce service
15154 not only adds the @code{xfce} metapackage to the system profile, but it
15155 also gives the Thunar file manager the ability to open a ``root-mode''
15156 file management window, if the user authenticates using the
15157 administrator's password via the standard polkit graphical interface.
15158 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
15159 appropriately, allowing MATE to operate with elevated privileges on a
15160 limited number of special-purpose system interfaces. Additionally,
15161 adding a service of type @code{mate-desktop-service-type} adds the MATE
15162 metapackage to the system profile. ``Adding Enlightenment'' means that
15163 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
15164 are set as setuid, allowing Enlightenment's screen locker and other
15165 functionality to work as expetected.
15167 The desktop environments in Guix use the Xorg display server by
15168 default. If you'd like to use the newer display server protocol
15169 called Wayland, you need to use the @code{sddm-service} instead of
15170 GDM as the graphical login manager. You should then
15171 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
15172 also try starting GNOME on Wayland manually from a TTY with the
15173 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
15174 gnome-session``. Currently only GNOME has support for Wayland.
15176 @defvr {Scheme Variable} gnome-desktop-service-type
15177 This is the type of the service that adds the @uref{https://www.gnome.org,
15178 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
15179 object (see below.)
15181 This service adds the @code{gnome} package to the system profile, and extends
15182 polkit with the actions from @code{gnome-settings-daemon}.
15185 @deftp {Data Type} gnome-desktop-configuration
15186 Configuration record for the GNOME desktop environment.
15189 @item @code{gnome} (default: @code{gnome})
15190 The GNOME package to use.
15194 @defvr {Scheme Variable} xfce-desktop-service-type
15195 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
15196 desktop environment. Its value is an @code{xfce-desktop-configuration} object
15199 This service adds the @code{xfce} package to the system profile, and
15200 extends polkit with the ability for @code{thunar} to manipulate the file
15201 system as root from within a user session, after the user has authenticated
15202 with the administrator's password.
15205 @deftp {Data Type} xfce-desktop-configuration
15206 Configuration record for the Xfce desktop environment.
15209 @item @code{xfce} (default: @code{xfce})
15210 The Xfce package to use.
15214 @deffn {Scheme Variable} mate-desktop-service-type
15215 This is the type of the service that runs the @uref{https://mate-desktop.org/,
15216 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
15217 object (see below.)
15219 This service adds the @code{mate} package to the system
15220 profile, and extends polkit with the actions from
15221 @code{mate-settings-daemon}.
15224 @deftp {Data Type} mate-desktop-configuration
15225 Configuration record for the MATE desktop environment.
15228 @item @code{mate} (default: @code{mate})
15229 The MATE package to use.
15233 @deffn {Scheme Variable} enlightenment-desktop-service-type
15234 Return a service that adds the @code{enlightenment} package to the system
15235 profile, and extends dbus with actions from @code{efl}.
15238 @deftp {Data Type} enlightenment-desktop-service-configuration
15240 @item @code{enlightenment} (default: @code{enlightenment})
15241 The enlightenment package to use.
15245 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
15246 the default @code{%desktop-services} variable doesn't include any of
15247 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
15248 @code{%desktop-services} in the @code{services} field of your
15249 @code{operating-system}:
15252 (use-modules (gnu))
15253 (use-service-modules desktop)
15256 ;; cons* adds items to the list given as its last argument.
15257 (services (cons* (service gnome-desktop-service-type)
15258 (service xfce-desktop-service)
15259 %desktop-services))
15263 These desktop environments will then be available as options in the
15264 graphical login window.
15266 The actual service definitions included in @code{%desktop-services} and
15267 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
15268 are described below.
15270 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
15271 Return a service that runs the ``system bus'', using @var{dbus}, with
15272 support for @var{services}.
15274 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
15275 facility. Its system bus is used to allow system services to communicate
15276 and to be notified of system-wide events.
15278 @var{services} must be a list of packages that provide an
15279 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
15280 and policy files. For example, to allow avahi-daemon to use the system bus,
15281 @var{services} must be equal to @code{(list avahi)}.
15284 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
15285 Return a service that runs the @code{elogind} login and
15286 seat management daemon. @uref{https://github.com/elogind/elogind,
15287 Elogind} exposes a D-Bus interface that can be used to know which users
15288 are logged in, know what kind of sessions they have open, suspend the
15289 system, inhibit system suspend, reboot the system, and other tasks.
15291 Elogind handles most system-level power events for a computer, for
15292 example suspending the system when a lid is closed, or shutting it down
15293 when the power button is pressed.
15295 The @var{config} keyword argument specifies the configuration for
15296 elogind, and should be the result of an @code{(elogind-configuration
15297 (@var{parameter} @var{value})...)} invocation. Available parameters and
15298 their default values are:
15301 @item kill-user-processes?
15303 @item kill-only-users
15305 @item kill-exclude-users
15307 @item inhibit-delay-max-seconds
15309 @item handle-power-key
15311 @item handle-suspend-key
15313 @item handle-hibernate-key
15315 @item handle-lid-switch
15317 @item handle-lid-switch-docked
15319 @item power-key-ignore-inhibited?
15321 @item suspend-key-ignore-inhibited?
15323 @item hibernate-key-ignore-inhibited?
15325 @item lid-switch-ignore-inhibited?
15327 @item holdoff-timeout-seconds
15331 @item idle-action-seconds
15333 @item runtime-directory-size-percent
15335 @item runtime-directory-size
15339 @item suspend-state
15340 @code{("mem" "standby" "freeze")}
15343 @item hibernate-state
15345 @item hibernate-mode
15346 @code{("platform" "shutdown")}
15347 @item hybrid-sleep-state
15349 @item hybrid-sleep-mode
15350 @code{("suspend" "platform" "shutdown")}
15354 @deffn {Scheme Procedure} accountsservice-service @
15355 [#:accountsservice @var{accountsservice}]
15356 Return a service that runs AccountsService, a system service that can
15357 list available accounts, change their passwords, and so on.
15358 AccountsService integrates with PolicyKit to enable unprivileged users
15359 to acquire the capability to modify their system configuration.
15360 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
15361 accountsservice web site} for more information.
15363 The @var{accountsservice} keyword argument is the @code{accountsservice}
15364 package to expose as a service.
15367 @deffn {Scheme Procedure} polkit-service @
15368 [#:polkit @var{polkit}]
15369 Return a service that runs the
15370 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
15371 management service}, which allows system administrators to grant access to
15372 privileged operations in a structured way. By querying the Polkit service, a
15373 privileged system component can know when it should grant additional
15374 capabilities to ordinary users. For example, an ordinary user can be granted
15375 the capability to suspend the system if the user is logged in locally.
15378 @defvr {Scheme Variable} upower-service-type
15379 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
15380 system-wide monitor for power consumption and battery levels, with the given
15381 configuration settings.
15383 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
15384 notably used by GNOME.
15387 @deftp {Data Type} upower-configuration
15388 Data type representation the configuration for UPower.
15392 @item @code{upower} (default: @var{upower})
15393 Package to use for @code{upower}.
15395 @item @code{watts-up-pro?} (default: @code{#f})
15396 Enable the Watts Up Pro device.
15398 @item @code{poll-batteries?} (default: @code{#t})
15399 Enable polling the kernel for battery level changes.
15401 @item @code{ignore-lid?} (default: @code{#f})
15402 Ignore the lid state, this can be useful if it's incorrect on a device.
15404 @item @code{use-percentage-for-policy?} (default: @code{#f})
15405 Whether battery percentage based policy should be used. The default is to use
15406 the time left, change to @code{#t} to use the percentage.
15408 @item @code{percentage-low} (default: @code{10})
15409 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15410 at which the battery is considered low.
15412 @item @code{percentage-critical} (default: @code{3})
15413 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15414 at which the battery is considered critical.
15416 @item @code{percentage-action} (default: @code{2})
15417 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15418 at which action will be taken.
15420 @item @code{time-low} (default: @code{1200})
15421 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15422 seconds at which the battery is considered low.
15424 @item @code{time-critical} (default: @code{300})
15425 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15426 seconds at which the battery is considered critical.
15428 @item @code{time-action} (default: @code{120})
15429 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15430 seconds at which action will be taken.
15432 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
15433 The action taken when @code{percentage-action} or @code{time-action} is
15434 reached (depending on the configuration of @code{use-percentage-for-policy?}).
15436 Possible values are:
15446 @code{'hybrid-sleep}.
15452 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
15453 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
15454 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
15455 notifications and ways to mount/unmount disks. Programs that talk to UDisks
15456 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
15459 @deffn {Scheme Procedure} colord-service [#:colord @var{colord}]
15460 Return a service that runs @command{colord}, a system service with a D-Bus
15461 interface to manage the color profiles of input and output devices such as
15462 screens and scanners. It is notably used by the GNOME Color Manager graphical
15463 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
15464 site} for more information.
15467 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
15468 Return a configuration allowing an application to access GeoClue
15469 location data. @var{name} is the Desktop ID of the application, without
15470 the @code{.desktop} part. If @var{allowed?} is true, the application
15471 will have access to location information by default. The boolean
15472 @var{system?} value indicates whether an application is a system component
15473 or not. Finally @var{users} is a list of UIDs of all users for which
15474 this application is allowed location info access. An empty users list
15475 means that all users are allowed.
15478 @defvr {Scheme Variable} %standard-geoclue-applications
15479 The standard list of well-known GeoClue application configurations,
15480 granting authority to the GNOME date-and-time utility to ask for the
15481 current location in order to set the time zone, and allowing the
15482 IceCat and Epiphany web browsers to request location information.
15483 IceCat and Epiphany both query the user before allowing a web page to
15484 know the user's location.
15487 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
15488 [#:whitelist '()] @
15489 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
15490 [#:submit-data? #f]
15491 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
15492 [#:submission-nick "geoclue"] @
15493 [#:applications %standard-geoclue-applications]
15494 Return a service that runs the GeoClue location service. This service
15495 provides a D-Bus interface to allow applications to request access to a
15496 user's physical location, and optionally to add information to online
15497 location databases. See
15498 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
15499 web site} for more information.
15502 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
15503 [@w{#:auto-enable? #f}]
15504 Return a service that runs the @command{bluetoothd} daemon, which
15505 manages all the Bluetooth devices and provides a number of D-Bus
15506 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
15507 powered automatically at boot, which can be useful when using a
15508 bluetooth keyboard or mouse.
15510 Users need to be in the @code{lp} group to access the D-Bus service.
15513 @node Sound Services
15514 @subsection Sound Services
15516 @cindex sound support
15518 @cindex PulseAudio, sound support
15520 The @code{(gnu services sound)} module provides a service to configure the
15521 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
15522 preferred ALSA output driver.
15524 @deffn {Scheme Variable} alsa-service-type
15525 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
15526 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
15527 configuration file. The value for this type is a @command{alsa-configuration}
15528 record as in this example:
15531 (service alsa-service-type)
15534 See below for details about @code{alsa-configuration}.
15537 @deftp {Data Type} alsa-configuration
15538 Data type representing the configuration for @code{alsa-service}.
15541 @item @code{alsa-plugins} (default: @var{alsa-plugins})
15542 @code{alsa-plugins} package to use.
15544 @item @code{pulseaudio?} (default: @var{#t})
15545 Whether ALSA applications should transparently be made to use the
15546 @uref{http://www.pulseaudio.org/, PulseAudio} sound server.
15548 Using PulseAudio allows you to run several sound-producing applications
15549 at the same time and to individual control them @i{via}
15550 @command{pavucontrol}, among other things.
15552 @item @code{extra-options} (default: @var{""})
15553 String to append to the @file{/etc/asound.conf} file.
15558 Individual users who want to override the system configuration of ALSA can do
15559 it with the @file{~/.asoundrc} file:
15562 # In guix, we have to specify the absolute path for plugins.
15564 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
15567 # Routing ALSA to jack:
15568 # <http://jackaudio.org/faq/routing_alsa.html>.
15572 0 system:playback_1
15573 1 system:playback_2
15590 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
15594 @node Database Services
15595 @subsection Database Services
15599 The @code{(gnu services databases)} module provides the following services.
15601 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
15602 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
15603 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
15604 Return a service that runs @var{postgresql}, the PostgreSQL database
15607 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
15608 creates a database cluster with @var{locale} as the default
15609 locale, stored in @var{data-directory}. It then listens on @var{port}.
15611 @cindex postgresql extension-packages
15612 Additional extensions are loaded from packages listed in
15613 @var{extension-packages}. Extensions are available at runtime. For instance,
15614 to create a geographic database using the @code{postgis} extension, a user can
15615 configure the postgresql-service as in this example:
15619 (use-package-modules databases geo)
15623 ;; postgresql is required to run `psql' but postgis is not required for
15624 ;; proper operation.
15625 (packages (cons* postgresql %base-packages))
15628 (postgresql-service #:extension-packages (list postgis))
15632 Then the extension becomes visible and you can initialise an empty geographic
15633 database in this way:
15637 > create database postgistest;
15638 > \connect postgistest;
15639 > create extension postgis;
15640 > create extension postgis_topology;
15643 There is no need to add this field for contrib extensions such as hstore or
15644 dblink as they are already loadable by postgresql. This field is only
15645 required to add extensions provided by other packages.
15648 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
15649 Return a service that runs @command{mysqld}, the MySQL or MariaDB
15652 The optional @var{config} argument specifies the configuration for
15653 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
15656 @deftp {Data Type} mysql-configuration
15657 Data type representing the configuration of @var{mysql-service}.
15660 @item @code{mysql} (default: @var{mariadb})
15661 Package object of the MySQL database server, can be either @var{mariadb}
15664 For MySQL, a temporary root password will be displayed at activation time.
15665 For MariaDB, the root password is empty.
15667 @item @code{port} (default: @code{3306})
15668 TCP port on which the database server listens for incoming connections.
15672 @defvr {Scheme Variable} memcached-service-type
15673 This is the service type for the @uref{https://memcached.org/,
15674 Memcached} service, which provides a distributed in memory cache. The
15675 value for the service type is a @code{memcached-configuration} object.
15679 (service memcached-service-type)
15682 @deftp {Data Type} memcached-configuration
15683 Data type representing the configuration of memcached.
15686 @item @code{memcached} (default: @code{memcached})
15687 The Memcached package to use.
15689 @item @code{interfaces} (default: @code{'("0.0.0.0")})
15690 Network interfaces on which to listen.
15692 @item @code{tcp-port} (default: @code{11211})
15693 Port on which to accept connections on,
15695 @item @code{udp-port} (default: @code{11211})
15696 Port on which to accept UDP connections on, a value of 0 will disable
15697 listening on a UDP socket.
15699 @item @code{additional-options} (default: @code{'()})
15700 Additional command line options to pass to @code{memcached}.
15704 @defvr {Scheme Variable} mongodb-service-type
15705 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
15706 The value for the service type is a @code{mongodb-configuration} object.
15710 (service mongodb-service-type)
15713 @deftp {Data Type} mongodb-configuration
15714 Data type representing the configuration of mongodb.
15717 @item @code{mongodb} (default: @code{mongodb})
15718 The MongoDB package to use.
15720 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
15721 The configuration file for MongoDB.
15723 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
15724 This value is used to create the directory, so that it exists and is
15725 owned by the mongodb user. It should match the data-directory which
15726 MongoDB is configured to use through the configuration file.
15730 @defvr {Scheme Variable} redis-service-type
15731 This is the service type for the @uref{https://redis.io/, Redis}
15732 key/value store, whose value is a @code{redis-configuration} object.
15735 @deftp {Data Type} redis-configuration
15736 Data type representing the configuration of redis.
15739 @item @code{redis} (default: @code{redis})
15740 The Redis package to use.
15742 @item @code{bind} (default: @code{"127.0.0.1"})
15743 Network interface on which to listen.
15745 @item @code{port} (default: @code{6379})
15746 Port on which to accept connections on, a value of 0 will disable
15747 listening on a TCP socket.
15749 @item @code{working-directory} (default: @code{"/var/lib/redis"})
15750 Directory in which to store the database and related files.
15754 @node Mail Services
15755 @subsection Mail Services
15759 The @code{(gnu services mail)} module provides Guix service definitions
15760 for email services: IMAP, POP3, and LMTP servers, as well as mail
15761 transport agents (MTAs). Lots of acronyms! These services are detailed
15762 in the subsections below.
15764 @subsubheading Dovecot Service
15766 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
15767 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
15770 By default, Dovecot does not need much configuration; the default
15771 configuration object created by @code{(dovecot-configuration)} will
15772 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
15773 certificate will be generated for TLS-protected connections, though
15774 Dovecot will also listen on cleartext ports by default. There are a
15775 number of options, though, which mail administrators might need to change,
15776 and as is the case with other services, Guix allows the system
15777 administrator to specify these parameters via a uniform Scheme interface.
15779 For example, to specify that mail is located at @code{maildir~/.mail},
15780 one would instantiate the Dovecot service like this:
15783 (dovecot-service #:config
15784 (dovecot-configuration
15785 (mail-location "maildir:~/.mail")))
15788 The available configuration parameters follow. Each parameter
15789 definition is preceded by its type; for example, @samp{string-list foo}
15790 indicates that the @code{foo} parameter should be specified as a list of
15791 strings. There is also a way to specify the configuration as a string,
15792 if you have an old @code{dovecot.conf} file that you want to port over
15793 from some other system; see the end for more details.
15795 @c The following documentation was initially generated by
15796 @c (generate-documentation) in (gnu services mail). Manually maintained
15797 @c documentation is better, so we shouldn't hesitate to edit below as
15798 @c needed. However if the change you want to make to this documentation
15799 @c can be done in an automated way, it's probably easier to change
15800 @c (generate-documentation) than to make it below and have to deal with
15801 @c the churn as dovecot updates.
15803 Available @code{dovecot-configuration} fields are:
15805 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
15806 The dovecot package.
15809 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
15810 A list of IPs or hosts where to listen for connections. @samp{*}
15811 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
15812 interfaces. If you want to specify non-default ports or anything more
15813 complex, customize the address and port fields of the
15814 @samp{inet-listener} of the specific services you are interested in.
15817 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
15818 List of protocols we want to serve. Available protocols include
15819 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
15821 Available @code{protocol-configuration} fields are:
15823 @deftypevr {@code{protocol-configuration} parameter} string name
15824 The name of the protocol.
15827 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
15828 UNIX socket path to the master authentication server to find users.
15829 This is used by imap (for shared users) and lda.
15830 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
15833 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
15834 Space separated list of plugins to load.
15837 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
15838 Maximum number of IMAP connections allowed for a user from each IP
15839 address. NOTE: The username is compared case-sensitively.
15840 Defaults to @samp{10}.
15845 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
15846 List of services to enable. Available services include @samp{imap},
15847 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
15850 Available @code{service-configuration} fields are:
15852 @deftypevr {@code{service-configuration} parameter} string kind
15853 The service kind. Valid values include @code{director},
15854 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
15855 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
15856 @code{tcpwrap}, @code{quota-warning}, or anything else.
15859 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
15860 Listeners for the service. A listener is either a
15861 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
15862 an @code{inet-listener-configuration}.
15863 Defaults to @samp{()}.
15865 Available @code{unix-listener-configuration} fields are:
15867 @deftypevr {@code{unix-listener-configuration} parameter} string path
15868 Path to the file, relative to @code{base-dir} field. This is also used as
15872 @deftypevr {@code{unix-listener-configuration} parameter} string mode
15873 The access mode for the socket.
15874 Defaults to @samp{"0600"}.
15877 @deftypevr {@code{unix-listener-configuration} parameter} string user
15878 The user to own the socket.
15879 Defaults to @samp{""}.
15882 @deftypevr {@code{unix-listener-configuration} parameter} string group
15883 The group to own the socket.
15884 Defaults to @samp{""}.
15888 Available @code{fifo-listener-configuration} fields are:
15890 @deftypevr {@code{fifo-listener-configuration} parameter} string path
15891 Path to the file, relative to @code{base-dir} field. This is also used as
15895 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
15896 The access mode for the socket.
15897 Defaults to @samp{"0600"}.
15900 @deftypevr {@code{fifo-listener-configuration} parameter} string user
15901 The user to own the socket.
15902 Defaults to @samp{""}.
15905 @deftypevr {@code{fifo-listener-configuration} parameter} string group
15906 The group to own the socket.
15907 Defaults to @samp{""}.
15911 Available @code{inet-listener-configuration} fields are:
15913 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
15914 The protocol to listen for.
15917 @deftypevr {@code{inet-listener-configuration} parameter} string address
15918 The address on which to listen, or empty for all addresses.
15919 Defaults to @samp{""}.
15922 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
15923 The port on which to listen.
15926 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
15927 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
15929 Defaults to @samp{#t}.
15934 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
15935 Maximum number of simultaneous client connections per process. Once
15936 this number of connections is received, the next incoming connection
15937 will prompt Dovecot to spawn another process. If set to 0,
15938 @code{default-client-limit} is used instead.
15940 Defaults to @samp{0}.
15944 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
15945 Number of connections to handle before starting a new process.
15946 Typically the only useful values are 0 (unlimited) or 1. 1 is more
15947 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
15948 Defaults to @samp{1}.
15952 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
15953 Maximum number of processes that can exist for this service. If set to
15954 0, @code{default-process-limit} is used instead.
15956 Defaults to @samp{0}.
15960 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
15961 Number of processes to always keep waiting for more connections.
15962 Defaults to @samp{0}.
15965 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
15966 If you set @samp{service-count 0}, you probably need to grow
15968 Defaults to @samp{256000000}.
15973 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
15974 Dict configuration, as created by the @code{dict-configuration}
15977 Available @code{dict-configuration} fields are:
15979 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
15980 A list of key-value pairs that this dict should hold.
15981 Defaults to @samp{()}.
15986 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
15987 A list of passdb configurations, each one created by the
15988 @code{passdb-configuration} constructor.
15990 Available @code{passdb-configuration} fields are:
15992 @deftypevr {@code{passdb-configuration} parameter} string driver
15993 The driver that the passdb should use. Valid values include
15994 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
15996 Defaults to @samp{"pam"}.
15999 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
16000 Space separated list of arguments to the passdb driver.
16001 Defaults to @samp{""}.
16006 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
16007 List of userdb configurations, each one created by the
16008 @code{userdb-configuration} constructor.
16010 Available @code{userdb-configuration} fields are:
16012 @deftypevr {@code{userdb-configuration} parameter} string driver
16013 The driver that the userdb should use. Valid values include
16014 @samp{passwd} and @samp{static}.
16015 Defaults to @samp{"passwd"}.
16018 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
16019 Space separated list of arguments to the userdb driver.
16020 Defaults to @samp{""}.
16023 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
16024 Override fields from passwd.
16025 Defaults to @samp{()}.
16030 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
16031 Plug-in configuration, created by the @code{plugin-configuration}
16035 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
16036 List of namespaces. Each item in the list is created by the
16037 @code{namespace-configuration} constructor.
16039 Available @code{namespace-configuration} fields are:
16041 @deftypevr {@code{namespace-configuration} parameter} string name
16042 Name for this namespace.
16045 @deftypevr {@code{namespace-configuration} parameter} string type
16046 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
16047 Defaults to @samp{"private"}.
16050 @deftypevr {@code{namespace-configuration} parameter} string separator
16051 Hierarchy separator to use. You should use the same separator for
16052 all namespaces or some clients get confused. @samp{/} is usually a good
16053 one. The default however depends on the underlying mail storage
16055 Defaults to @samp{""}.
16058 @deftypevr {@code{namespace-configuration} parameter} string prefix
16059 Prefix required to access this namespace. This needs to be
16060 different for all namespaces. For example @samp{Public/}.
16061 Defaults to @samp{""}.
16064 @deftypevr {@code{namespace-configuration} parameter} string location
16065 Physical location of the mailbox. This is in the same format as
16066 mail_location, which is also the default for it.
16067 Defaults to @samp{""}.
16070 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
16071 There can be only one INBOX, and this setting defines which
16073 Defaults to @samp{#f}.
16076 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
16077 If namespace is hidden, it's not advertised to clients via NAMESPACE
16078 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
16079 useful when converting from another server with different namespaces
16080 which you want to deprecate but still keep working. For example you can
16081 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
16083 Defaults to @samp{#f}.
16086 @deftypevr {@code{namespace-configuration} parameter} boolean list?
16087 Show the mailboxes under this namespace with the LIST command. This
16088 makes the namespace visible for clients that do not support the NAMESPACE
16089 extension. The special @code{children} value lists child mailboxes, but
16090 hides the namespace prefix.
16091 Defaults to @samp{#t}.
16094 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
16095 Namespace handles its own subscriptions. If set to @code{#f}, the
16096 parent namespace handles them. The empty prefix should always have this
16098 Defaults to @samp{#t}.
16101 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
16102 List of predefined mailboxes in this namespace.
16103 Defaults to @samp{()}.
16105 Available @code{mailbox-configuration} fields are:
16107 @deftypevr {@code{mailbox-configuration} parameter} string name
16108 Name for this mailbox.
16111 @deftypevr {@code{mailbox-configuration} parameter} string auto
16112 @samp{create} will automatically create this mailbox.
16113 @samp{subscribe} will both create and subscribe to the mailbox.
16114 Defaults to @samp{"no"}.
16117 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
16118 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
16119 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
16120 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
16121 Defaults to @samp{()}.
16128 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
16129 Base directory where to store runtime data.
16130 Defaults to @samp{"/var/run/dovecot/"}.
16133 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
16134 Greeting message for clients.
16135 Defaults to @samp{"Dovecot ready."}.
16138 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
16139 List of trusted network ranges. Connections from these IPs are
16140 allowed to override their IP addresses and ports (for logging and for
16141 authentication checks). @samp{disable-plaintext-auth} is also ignored
16142 for these networks. Typically you would specify your IMAP proxy servers
16144 Defaults to @samp{()}.
16147 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
16148 List of login access check sockets (e.g.@: tcpwrap).
16149 Defaults to @samp{()}.
16152 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
16153 Show more verbose process titles (in ps). Currently shows user name
16154 and IP address. Useful for seeing who is actually using the IMAP
16155 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
16157 Defaults to @samp{#f}.
16160 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
16161 Should all processes be killed when Dovecot master process shuts down.
16162 Setting this to @code{#f} means that Dovecot can be upgraded without
16163 forcing existing client connections to close (although that could also
16164 be a problem if the upgrade is e.g.@: due to a security fix).
16165 Defaults to @samp{#t}.
16168 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
16169 If non-zero, run mail commands via this many connections to doveadm
16170 server, instead of running them directly in the same process.
16171 Defaults to @samp{0}.
16174 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
16175 UNIX socket or host:port used for connecting to doveadm server.
16176 Defaults to @samp{"doveadm-server"}.
16179 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
16180 List of environment variables that are preserved on Dovecot startup
16181 and passed down to all of its child processes. You can also give
16182 key=value pairs to always set specific settings.
16185 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
16186 Disable LOGIN command and all other plaintext authentications unless
16187 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
16188 matches the local IP (i.e.@: you're connecting from the same computer),
16189 the connection is considered secure and plaintext authentication is
16190 allowed. See also ssl=required setting.
16191 Defaults to @samp{#t}.
16194 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
16195 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
16196 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
16197 for caching to be used.
16198 Defaults to @samp{0}.
16201 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
16202 Time to live for cached data. After TTL expires the cached record
16203 is no longer used, *except* if the main database lookup returns internal
16204 failure. We also try to handle password changes automatically: If
16205 user's previous authentication was successful, but this one wasn't, the
16206 cache isn't used. For now this works only with plaintext
16208 Defaults to @samp{"1 hour"}.
16211 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
16212 TTL for negative hits (user not found, password mismatch).
16213 0 disables caching them completely.
16214 Defaults to @samp{"1 hour"}.
16217 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
16218 List of realms for SASL authentication mechanisms that need them.
16219 You can leave it empty if you don't want to support multiple realms.
16220 Many clients simply use the first one listed here, so keep the default
16222 Defaults to @samp{()}.
16225 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
16226 Default realm/domain to use if none was specified. This is used for
16227 both SASL realms and appending @@domain to username in plaintext
16229 Defaults to @samp{""}.
16232 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
16233 List of allowed characters in username. If the user-given username
16234 contains a character not listed in here, the login automatically fails.
16235 This is just an extra check to make sure user can't exploit any
16236 potential quote escaping vulnerabilities with SQL/LDAP databases. If
16237 you want to allow all characters, set this value to empty.
16238 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
16241 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
16242 Username character translations before it's looked up from
16243 databases. The value contains series of from -> to characters. For
16244 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
16245 translated to @samp{@@}.
16246 Defaults to @samp{""}.
16249 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
16250 Username formatting before it's looked up from databases. You can
16251 use the standard variables here, e.g.@: %Lu would lowercase the username,
16252 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
16253 change the @samp{@@} into @samp{-AT-}. This translation is done after
16254 @samp{auth-username-translation} changes.
16255 Defaults to @samp{"%Lu"}.
16258 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
16259 If you want to allow master users to log in by specifying the master
16260 username within the normal username string (i.e.@: not using SASL
16261 mechanism's support for it), you can specify the separator character
16262 here. The format is then <username><separator><master username>.
16263 UW-IMAP uses @samp{*} as the separator, so that could be a good
16265 Defaults to @samp{""}.
16268 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
16269 Username to use for users logging in with ANONYMOUS SASL
16271 Defaults to @samp{"anonymous"}.
16274 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
16275 Maximum number of dovecot-auth worker processes. They're used to
16276 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
16277 They're automatically created and destroyed as needed.
16278 Defaults to @samp{30}.
16281 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
16282 Host name to use in GSSAPI principal names. The default is to use
16283 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
16284 allow all keytab entries.
16285 Defaults to @samp{""}.
16288 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
16289 Kerberos keytab to use for the GSSAPI mechanism. Will use the
16290 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
16291 need to change the auth service to run as root to be able to read this
16293 Defaults to @samp{""}.
16296 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
16297 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
16298 and @samp{ntlm-auth} helper.
16299 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
16300 Defaults to @samp{#f}.
16303 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
16304 Path for Samba's @samp{ntlm-auth} helper binary.
16305 Defaults to @samp{"/usr/bin/ntlm_auth"}.
16308 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
16309 Time to delay before replying to failed authentications.
16310 Defaults to @samp{"2 secs"}.
16313 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
16314 Require a valid SSL client certificate or the authentication
16316 Defaults to @samp{#f}.
16319 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
16320 Take the username from client's SSL certificate, using
16321 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
16323 Defaults to @samp{#f}.
16326 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
16327 List of wanted authentication mechanisms. Supported mechanisms are:
16328 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
16329 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
16330 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
16331 @samp{disable-plaintext-auth} setting.
16334 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
16335 List of IPs or hostnames to all director servers, including ourself.
16336 Ports can be specified as ip:port. The default port is the same as what
16337 director service's @samp{inet-listener} is using.
16338 Defaults to @samp{()}.
16341 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
16342 List of IPs or hostnames to all backend mail servers. Ranges are
16343 allowed too, like 10.0.0.10-10.0.0.30.
16344 Defaults to @samp{()}.
16347 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
16348 How long to redirect users to a specific server after it no longer
16349 has any connections.
16350 Defaults to @samp{"15 min"}.
16353 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
16354 How the username is translated before being hashed. Useful values
16355 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
16356 are shared within domain.
16357 Defaults to @samp{"%Lu"}.
16360 @deftypevr {@code{dovecot-configuration} parameter} string log-path
16361 Log file to use for error messages. @samp{syslog} logs to syslog,
16362 @samp{/dev/stderr} logs to stderr.
16363 Defaults to @samp{"syslog"}.
16366 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
16367 Log file to use for informational messages. Defaults to
16369 Defaults to @samp{""}.
16372 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
16373 Log file to use for debug messages. Defaults to
16374 @samp{info-log-path}.
16375 Defaults to @samp{""}.
16378 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
16379 Syslog facility to use if you're logging to syslog. Usually if you
16380 don't want to use @samp{mail}, you'll use local0..local7. Also other
16381 standard facilities are supported.
16382 Defaults to @samp{"mail"}.
16385 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
16386 Log unsuccessful authentication attempts and the reasons why they
16388 Defaults to @samp{#f}.
16391 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
16392 In case of password mismatches, log the attempted password. Valid
16393 values are no, plain and sha1. sha1 can be useful for detecting brute
16394 force password attempts vs. user simply trying the same password over
16395 and over again. You can also truncate the value to n chars by appending
16396 ":n" (e.g.@: sha1:6).
16397 Defaults to @samp{"no"}.
16400 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
16401 Even more verbose logging for debugging purposes. Shows for example
16403 Defaults to @samp{#f}.
16406 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
16407 In case of password mismatches, log the passwords and used scheme so
16408 the problem can be debugged. Enabling this also enables
16410 Defaults to @samp{#f}.
16413 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
16414 Enable mail process debugging. This can help you figure out why
16415 Dovecot isn't finding your mails.
16416 Defaults to @samp{#f}.
16419 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
16420 Show protocol level SSL errors.
16421 Defaults to @samp{#f}.
16424 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
16425 Prefix for each line written to log file. % codes are in
16426 strftime(3) format.
16427 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
16430 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
16431 List of elements we want to log. The elements which have a
16432 non-empty variable value are joined together to form a comma-separated
16436 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
16437 Login log format. %s contains @samp{login-log-format-elements}
16438 string, %$ contains the data we want to log.
16439 Defaults to @samp{"%$: %s"}.
16442 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
16443 Log prefix for mail processes. See doc/wiki/Variables.txt for list
16444 of possible variables you can use.
16445 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
16448 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
16449 Format to use for logging mail deliveries. You can use variables:
16452 Delivery status message (e.g.@: @samp{saved to INBOX})
16464 Defaults to @samp{"msgid=%m: %$"}.
16467 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
16468 Location for users' mailboxes. The default is empty, which means
16469 that Dovecot tries to find the mailboxes automatically. This won't work
16470 if the user doesn't yet have any mail, so you should explicitly tell
16471 Dovecot the full location.
16473 If you're using mbox, giving a path to the INBOX
16474 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
16475 where the other mailboxes are kept. This is called the "root mail
16476 directory", and it must be the first path given in the
16477 @samp{mail-location} setting.
16479 There are a few special variables you can use, eg.:
16485 user part in user@@domain, same as %u if there's no domain
16487 domain part in user@@domain, empty if there's no domain
16492 See doc/wiki/Variables.txt for full list. Some examples:
16494 @item maildir:~/Maildir
16495 @item mbox:~/mail:INBOX=/var/mail/%u
16496 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
16498 Defaults to @samp{""}.
16501 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
16502 System user and group used to access mails. If you use multiple,
16503 userdb can override these by returning uid or gid fields. You can use
16504 either numbers or names. <doc/wiki/UserIds.txt>.
16505 Defaults to @samp{""}.
16508 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
16510 Defaults to @samp{""}.
16513 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
16514 Group to enable temporarily for privileged operations. Currently
16515 this is used only with INBOX when either its initial creation or
16516 dotlocking fails. Typically this is set to "mail" to give access to
16518 Defaults to @samp{""}.
16521 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
16522 Grant access to these supplementary groups for mail processes.
16523 Typically these are used to set up access to shared mailboxes. Note
16524 that it may be dangerous to set these if users can create
16525 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
16526 could allow a user to delete others' mailboxes, or ln -s
16527 /secret/shared/box ~/mail/mybox would allow reading it).
16528 Defaults to @samp{""}.
16531 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
16532 Allow full file system access to clients. There's no access checks
16533 other than what the operating system does for the active UID/GID. It
16534 works with both maildir and mboxes, allowing you to prefix mailboxes
16535 names with e.g.@: /path/ or ~user/.
16536 Defaults to @samp{#f}.
16539 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
16540 Don't use mmap() at all. This is required if you store indexes to
16541 shared file systems (NFS or clustered file system).
16542 Defaults to @samp{#f}.
16545 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
16546 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
16547 supports @samp{O_EXCL} since version 3, so this should be safe to use
16548 nowadays by default.
16549 Defaults to @samp{#t}.
16552 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
16553 When to use fsync() or fdatasync() calls:
16556 Whenever necessary to avoid losing important data
16558 Useful with e.g.@: NFS when write()s are delayed
16560 Never use it (best performance, but crashes can lose data).
16562 Defaults to @samp{"optimized"}.
16565 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
16566 Mail storage exists in NFS. Set this to yes to make Dovecot flush
16567 NFS caches whenever needed. If you're using only a single mail server
16569 Defaults to @samp{#f}.
16572 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
16573 Mail index files also exist in NFS. Setting this to yes requires
16574 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
16575 Defaults to @samp{#f}.
16578 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
16579 Locking method for index files. Alternatives are fcntl, flock and
16580 dotlock. Dotlocking uses some tricks which may create more disk I/O
16581 than other locking methods. NFS users: flock doesn't work, remember to
16582 change @samp{mmap-disable}.
16583 Defaults to @samp{"fcntl"}.
16586 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
16587 Directory in which LDA/LMTP temporarily stores incoming mails >128
16589 Defaults to @samp{"/tmp"}.
16592 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
16593 Valid UID range for users. This is mostly to make sure that users can't
16594 log in as daemons or other system users. Note that denying root logins is
16595 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
16597 Defaults to @samp{500}.
16600 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
16602 Defaults to @samp{0}.
16605 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
16606 Valid GID range for users. Users having non-valid GID as primary group ID
16607 aren't allowed to log in. If user belongs to supplementary groups with
16608 non-valid GIDs, those groups are not set.
16609 Defaults to @samp{1}.
16612 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
16614 Defaults to @samp{0}.
16617 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
16618 Maximum allowed length for mail keyword name. It's only forced when
16619 trying to create new keywords.
16620 Defaults to @samp{50}.
16623 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
16624 List of directories under which chrooting is allowed for mail
16625 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
16626 too). This setting doesn't affect @samp{login-chroot}
16627 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
16628 "/./" in home dirs are ignored. WARNING: Never add directories here
16629 which local users can modify, that may lead to root exploit. Usually
16630 this should be done only if you don't allow shell access for users.
16631 <doc/wiki/Chrooting.txt>.
16632 Defaults to @samp{()}.
16635 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
16636 Default chroot directory for mail processes. This can be overridden
16637 for specific users in user database by giving /./ in user's home
16638 directory (e.g.@: /home/./user chroots into /home). Note that usually
16639 there is no real need to do chrooting, Dovecot doesn't allow users to
16640 access files outside their mail directory anyway. If your home
16641 directories are prefixed with the chroot directory, append "/."@: to
16642 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
16643 Defaults to @samp{""}.
16646 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
16647 UNIX socket path to master authentication server to find users.
16648 This is used by imap (for shared users) and lda.
16649 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16652 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
16653 Directory where to look up mail plugins.
16654 Defaults to @samp{"/usr/lib/dovecot"}.
16657 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
16658 List of plugins to load for all services. Plugins specific to IMAP,
16659 LDA, etc.@: are added to this list in their own .conf files.
16660 Defaults to @samp{()}.
16663 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
16664 The minimum number of mails in a mailbox before updates are done to
16665 cache file. This allows optimizing Dovecot's behavior to do less disk
16666 writes at the cost of more disk reads.
16667 Defaults to @samp{0}.
16670 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
16671 When IDLE command is running, mailbox is checked once in a while to
16672 see if there are any new mails or other changes. This setting defines
16673 the minimum time to wait between those checks. Dovecot can also use
16674 dnotify, inotify and kqueue to find out immediately when changes
16676 Defaults to @samp{"30 secs"}.
16679 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
16680 Save mails with CR+LF instead of plain LF. This makes sending those
16681 mails take less CPU, especially with sendfile() syscall with Linux and
16682 FreeBSD. But it also creates a bit more disk I/O which may just make it
16683 slower. Also note that if other software reads the mboxes/maildirs,
16684 they may handle the extra CRs wrong and cause problems.
16685 Defaults to @samp{#f}.
16688 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
16689 By default LIST command returns all entries in maildir beginning
16690 with a dot. Enabling this option makes Dovecot return only entries
16691 which are directories. This is done by stat()ing each entry, so it
16692 causes more disk I/O.
16693 (For systems setting struct @samp{dirent->d_type} this check is free
16694 and it's done always regardless of this setting).
16695 Defaults to @samp{#f}.
16698 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
16699 When copying a message, do it with hard links whenever possible.
16700 This makes the performance much better, and it's unlikely to have any
16702 Defaults to @samp{#t}.
16705 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
16706 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
16707 directory only when its mtime changes unexpectedly or when we can't find
16708 the mail otherwise.
16709 Defaults to @samp{#f}.
16712 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
16713 Which locking methods to use for locking mbox. There are four
16718 Create <mailbox>.lock file. This is the oldest and most NFS-safe
16719 solution. If you want to use /var/mail/ like directory, the users will
16720 need write access to that directory.
16722 Same as dotlock, but if it fails because of permissions or because there
16723 isn't enough disk space, just skip it.
16725 Use this if possible. Works with NFS too if lockd is used.
16727 May not exist in all systems. Doesn't work with NFS.
16729 May not exist in all systems. Doesn't work with NFS.
16732 You can use multiple locking methods; if you do the order they're declared
16733 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
16734 locking methods as well. Some operating systems don't allow using some of
16735 them simultaneously.
16738 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
16742 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
16743 Maximum time to wait for lock (all of them) before aborting.
16744 Defaults to @samp{"5 mins"}.
16747 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
16748 If dotlock exists but the mailbox isn't modified in any way,
16749 override the lock file after this much time.
16750 Defaults to @samp{"2 mins"}.
16753 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
16754 When mbox changes unexpectedly we have to fully read it to find out
16755 what changed. If the mbox is large this can take a long time. Since
16756 the change is usually just a newly appended mail, it'd be faster to
16757 simply read the new mails. If this setting is enabled, Dovecot does
16758 this but still safely fallbacks to re-reading the whole mbox file
16759 whenever something in mbox isn't how it's expected to be. The only real
16760 downside to this setting is that if some other MUA changes message
16761 flags, Dovecot doesn't notice it immediately. Note that a full sync is
16762 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
16763 Defaults to @samp{#t}.
16766 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
16767 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
16768 EXAMINE, EXPUNGE or CHECK commands. If this is set,
16769 @samp{mbox-dirty-syncs} is ignored.
16770 Defaults to @samp{#f}.
16773 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
16774 Delay writing mbox headers until doing a full write sync (EXPUNGE
16775 and CHECK commands and when closing the mailbox). This is especially
16776 useful for POP3 where clients often delete all mails. The downside is
16777 that our changes aren't immediately visible to other MUAs.
16778 Defaults to @samp{#t}.
16781 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
16782 If mbox size is smaller than this (e.g.@: 100k), don't write index
16783 files. If an index file already exists it's still read, just not
16785 Defaults to @samp{0}.
16788 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
16789 Maximum dbox file size until it's rotated.
16790 Defaults to @samp{10000000}.
16793 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
16794 Maximum dbox file age until it's rotated. Typically in days. Day
16795 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
16797 Defaults to @samp{"1d"}.
16800 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
16801 When creating new mdbox files, immediately preallocate their size to
16802 @samp{mdbox-rotate-size}. This setting currently works only in Linux
16803 with some file systems (ext4, xfs).
16804 Defaults to @samp{#f}.
16807 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
16808 sdbox and mdbox support saving mail attachments to external files,
16809 which also allows single instance storage for them. Other backends
16810 don't support this for now.
16812 WARNING: This feature hasn't been tested much yet. Use at your own risk.
16814 Directory root where to store mail attachments. Disabled, if empty.
16815 Defaults to @samp{""}.
16818 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
16819 Attachments smaller than this aren't saved externally. It's also
16820 possible to write a plugin to disable saving specific attachments
16822 Defaults to @samp{128000}.
16825 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
16826 File system backend to use for saving attachments:
16829 No SiS done by Dovecot (but this might help FS's own deduplication)
16831 SiS with immediate byte-by-byte comparison during saving
16832 @item sis-queue posix
16833 SiS with delayed comparison and deduplication.
16835 Defaults to @samp{"sis posix"}.
16838 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
16839 Hash format to use in attachment filenames. You can add any text and
16840 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
16841 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
16842 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
16843 Defaults to @samp{"%@{sha1@}"}.
16846 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
16848 Defaults to @samp{100}.
16851 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
16853 Defaults to @samp{1000}.
16856 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
16857 Default VSZ (virtual memory size) limit for service processes.
16858 This is mainly intended to catch and kill processes that leak memory
16859 before they eat up everything.
16860 Defaults to @samp{256000000}.
16863 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
16864 Login user is internally used by login processes. This is the most
16865 untrusted user in Dovecot system. It shouldn't have access to anything
16867 Defaults to @samp{"dovenull"}.
16870 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
16871 Internal user is used by unprivileged processes. It should be
16872 separate from login user, so that login processes can't disturb other
16874 Defaults to @samp{"dovecot"}.
16877 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
16878 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
16879 Defaults to @samp{"required"}.
16882 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
16883 PEM encoded X.509 SSL/TLS certificate (public key).
16884 Defaults to @samp{"</etc/dovecot/default.pem"}.
16887 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
16888 PEM encoded SSL/TLS private key. The key is opened before
16889 dropping root privileges, so keep the key file unreadable by anyone but
16891 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
16894 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
16895 If key file is password protected, give the password here.
16896 Alternatively give it when starting dovecot with -p parameter. Since
16897 this file is often world-readable, you may want to place this setting
16898 instead to a different.
16899 Defaults to @samp{""}.
16902 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
16903 PEM encoded trusted certificate authority. Set this only if you
16904 intend to use @samp{ssl-verify-client-cert? #t}. The file should
16905 contain the CA certificate(s) followed by the matching
16906 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
16907 Defaults to @samp{""}.
16910 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
16911 Require that CRL check succeeds for client certificates.
16912 Defaults to @samp{#t}.
16915 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
16916 Request client to send a certificate. If you also want to require
16917 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
16918 Defaults to @samp{#f}.
16921 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
16922 Which field from certificate to use for username. commonName and
16923 x500UniqueIdentifier are the usual choices. You'll also need to set
16924 @samp{auth-ssl-username-from-cert? #t}.
16925 Defaults to @samp{"commonName"}.
16928 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
16929 Minimum SSL protocol version to accept.
16930 Defaults to @samp{"TLSv1"}.
16933 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
16934 SSL ciphers to use.
16935 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
16938 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
16939 SSL crypto device to use, for valid values run "openssl engine".
16940 Defaults to @samp{""}.
16943 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
16944 Address to use when sending rejection mails.
16945 %d expands to recipient domain.
16946 Defaults to @samp{"postmaster@@%d"}.
16949 @deftypevr {@code{dovecot-configuration} parameter} string hostname
16950 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
16951 and in LMTP replies. Default is the system's real hostname@@domain.
16952 Defaults to @samp{""}.
16955 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
16956 If user is over quota, return with temporary failure instead of
16958 Defaults to @samp{#f}.
16961 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
16962 Binary to use for sending mails.
16963 Defaults to @samp{"/usr/sbin/sendmail"}.
16966 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
16967 If non-empty, send mails via this SMTP host[:port] instead of
16969 Defaults to @samp{""}.
16972 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
16973 Subject: header to use for rejection mails. You can use the same
16974 variables as for @samp{rejection-reason} below.
16975 Defaults to @samp{"Rejected: %s"}.
16978 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
16979 Human readable error message for rejection mails. You can use
16992 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
16995 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
16996 Delimiter character between local-part and detail in email
16998 Defaults to @samp{"+"}.
17001 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
17002 Header where the original recipient address (SMTP's RCPT TO:
17003 address) is taken from if not available elsewhere. With dovecot-lda -a
17004 parameter overrides this. A commonly used header for this is
17006 Defaults to @samp{""}.
17009 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
17010 Should saving a mail to a nonexistent mailbox automatically create
17012 Defaults to @samp{#f}.
17015 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
17016 Should automatically created mailboxes be also automatically
17018 Defaults to @samp{#f}.
17021 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
17022 Maximum IMAP command line length. Some clients generate very long
17023 command lines with huge mailboxes, so you may need to raise this if you
17024 get "Too long argument" or "IMAP command line too large" errors
17026 Defaults to @samp{64000}.
17029 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
17030 IMAP logout format string:
17033 total number of bytes read from client
17035 total number of bytes sent to client.
17037 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
17038 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@}"}.
17041 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
17042 Override the IMAP CAPABILITY response. If the value begins with '+',
17043 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
17044 Defaults to @samp{""}.
17047 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
17048 How long to wait between "OK Still here" notifications when client
17050 Defaults to @samp{"2 mins"}.
17053 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
17054 ID field names and values to send to clients. Using * as the value
17055 makes Dovecot use the default value. The following fields have default
17056 values currently: name, version, os, os-version, support-url,
17058 Defaults to @samp{""}.
17061 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
17062 ID fields sent by client to log. * means everything.
17063 Defaults to @samp{""}.
17066 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
17067 Workarounds for various client bugs:
17070 @item delay-newmail
17071 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
17072 CHECK commands. Some clients ignore them otherwise, for example OSX
17073 Mail (<v2.1). Outlook Express breaks more badly though, without this it
17074 may show user "Message no longer in server" errors. Note that OE6
17075 still breaks even with this workaround if synchronization is set to
17078 @item tb-extra-mailbox-sep
17079 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
17080 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
17081 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
17083 @item tb-lsub-flags
17084 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
17085 This makes Thunderbird realize they aren't selectable and show them
17086 greyed out, instead of only later giving "not selectable" popup error.
17088 Defaults to @samp{()}.
17091 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
17092 Host allowed in URLAUTH URLs sent by client. "*" allows all.
17093 Defaults to @samp{""}.
17097 Whew! Lots of configuration options. The nice thing about it though is
17098 that Guix has a complete interface to Dovecot's configuration
17099 language. This allows not only a nice way to declare configurations,
17100 but also offers reflective capabilities as well: users can write code to
17101 inspect and transform configurations from within Scheme.
17103 However, it could be that you just want to get a @code{dovecot.conf} up
17104 and running. In that case, you can pass an
17105 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
17106 @code{dovecot-service}. As its name indicates, an opaque configuration
17107 does not have easy reflective capabilities.
17109 Available @code{opaque-dovecot-configuration} fields are:
17111 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
17112 The dovecot package.
17115 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
17116 The contents of the @code{dovecot.conf}, as a string.
17119 For example, if your @code{dovecot.conf} is just the empty string, you
17120 could instantiate a dovecot service like this:
17123 (dovecot-service #:config
17124 (opaque-dovecot-configuration
17128 @subsubheading OpenSMTPD Service
17130 @deffn {Scheme Variable} opensmtpd-service-type
17131 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
17132 service, whose value should be an @code{opensmtpd-configuration} object
17133 as in this example:
17136 (service opensmtpd-service-type
17137 (opensmtpd-configuration
17138 (config-file (local-file "./my-smtpd.conf"))))
17142 @deftp {Data Type} opensmtpd-configuration
17143 Data type representing the configuration of opensmtpd.
17146 @item @code{package} (default: @var{opensmtpd})
17147 Package object of the OpenSMTPD SMTP server.
17149 @item @code{config-file} (default: @code{%default-opensmtpd-file})
17150 File-like object of the OpenSMTPD configuration file to use. By default
17151 it listens on the loopback network interface, and allows for mail from
17152 users and daemons on the local machine, as well as permitting email to
17153 remote servers. Run @command{man smtpd.conf} for more information.
17158 @subsubheading Exim Service
17160 @cindex mail transfer agent (MTA)
17161 @cindex MTA (mail transfer agent)
17164 @deffn {Scheme Variable} exim-service-type
17165 This is the type of the @uref{https://exim.org, Exim} mail transfer
17166 agent (MTA), whose value should be an @code{exim-configuration} object
17167 as in this example:
17170 (service exim-service-type
17171 (exim-configuration
17172 (config-file (local-file "./my-exim.conf"))))
17176 In order to use an @code{exim-service-type} service you must also have a
17177 @code{mail-aliases-service-type} service present in your
17178 @code{operating-system} (even if it has no aliases).
17180 @deftp {Data Type} exim-configuration
17181 Data type representing the configuration of exim.
17184 @item @code{package} (default: @var{exim})
17185 Package object of the Exim server.
17187 @item @code{config-file} (default: @code{#f})
17188 File-like object of the Exim configuration file to use. If its value is
17189 @code{#f} then use the default configuration file from the package
17190 provided in @code{package}. The resulting configuration file is loaded
17191 after setting the @code{exim_user} and @code{exim_group} configuration
17197 @subsubheading Getmail service
17202 @deffn {Scheme Variable} getmail-service-type
17203 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
17204 mail retriever, whose value should be an @code{getmail-configuration}.
17207 Available @code{getmail-configuration} fields are:
17209 @deftypevr {@code{getmail-configuration} parameter} symbol name
17210 A symbol to identify the getmail service.
17212 Defaults to @samp{"unset"}.
17216 @deftypevr {@code{getmail-configuration} parameter} package package
17217 The getmail package to use.
17221 @deftypevr {@code{getmail-configuration} parameter} string user
17222 The user to run getmail as.
17224 Defaults to @samp{"getmail"}.
17228 @deftypevr {@code{getmail-configuration} parameter} string group
17229 The group to run getmail as.
17231 Defaults to @samp{"getmail"}.
17235 @deftypevr {@code{getmail-configuration} parameter} string directory
17236 The getmail directory to use.
17238 Defaults to @samp{"/var/lib/getmail/default"}.
17242 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
17243 The getmail configuration file to use.
17245 Available @code{getmail-configuration-file} fields are:
17247 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
17248 What mail account to retrieve mail from, and how to access that account.
17250 Available @code{getmail-retriever-configuration} fields are:
17252 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
17253 The type of mail retriever to use. Valid values include @samp{passwd}
17256 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
17260 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
17261 Space separated list of arguments to the userdb driver.
17263 Defaults to @samp{unset}.
17267 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
17268 Space separated list of arguments to the userdb driver.
17270 Defaults to @samp{unset}.
17274 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
17275 Space separated list of arguments to the userdb driver.
17277 Defaults to @samp{#f}.
17281 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
17282 Override fields from passwd.
17284 Defaults to @samp{""}.
17288 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
17289 Override fields from passwd.
17291 Defaults to @samp{()}.
17295 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
17296 PEM-formatted key file to use for the TLS negotiation
17298 Defaults to @samp{""}.
17302 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
17303 PEM-formatted certificate file to use for the TLS negotiation
17305 Defaults to @samp{""}.
17309 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
17310 CA certificates to use
17312 Defaults to @samp{""}.
17316 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
17317 Extra retriever parameters
17319 Defaults to @samp{()}.
17325 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
17326 What to do with retrieved messages.
17328 Available @code{getmail-destination-configuration} fields are:
17330 @deftypevr {@code{getmail-destination-configuration} parameter} string type
17331 The type of mail destination. Valid values include @samp{Maildir},
17332 @samp{Mboxrd} and @samp{MDA_external}.
17334 Defaults to @samp{unset}.
17338 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
17339 The path option for the mail destination. The behaviour depends on the
17342 Defaults to @samp{""}.
17346 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
17347 Extra destination parameters
17349 Defaults to @samp{()}.
17355 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
17358 Available @code{getmail-options-configuration} fields are:
17360 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
17361 If set to @samp{0}, getmail will only print warnings and errors. A
17362 value of @samp{1} means that messages will be printed about retrieving
17363 and deleting messages. If set to @samp{2}, getmail will print messages
17364 about each of it's actions.
17366 Defaults to @samp{1}.
17370 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
17371 If true, getmail will retrieve all available messages. Otherwise it
17372 will only retrieve messages it hasn't seen previously.
17374 Defaults to @samp{#t}.
17378 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
17379 If set to true, messages will be deleted from the server after
17380 retrieving and successfully delivering them. Otherwise, messages will
17381 be left on the server.
17383 Defaults to @samp{#f}.
17387 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
17388 Getmail will delete messages this number of days after seeing them, if
17389 they have not been delivered. This means messages will be left on the
17390 server this number of days after delivering them. A value of @samp{0}
17391 disabled this feature.
17393 Defaults to @samp{0}.
17397 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
17398 Delete messages larger than this of bytes after retrieving them, even if
17399 the delete and delete-after options are disabled. A value of @samp{0}
17400 disables this feature.
17402 Defaults to @samp{0}.
17406 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
17407 Retrieve messages totalling up to this number of bytes before closing
17408 the session with the server. A value of @samp{0} disables this feature.
17410 Defaults to @samp{0}.
17414 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
17415 Don't retrieve messages larger than this number of bytes. A value of
17416 @samp{0} disables this feature.
17418 Defaults to @samp{0}.
17422 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
17423 If true, getmail will add a Delivered-To header to messages.
17425 Defaults to @samp{#t}.
17429 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
17430 If set, getmail adds a Received header to the messages.
17432 Defaults to @samp{#t}.
17436 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
17437 Getmail will record a log of its actions to the named file. A value of
17438 @samp{""} disables this feature.
17440 Defaults to @samp{""}.
17444 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
17445 If true, getmail will record a log of its actions using the system
17448 Defaults to @samp{#t}.
17452 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
17453 If true, getmail will log information about messages not retrieved and
17454 the reason for not retrieving them, as well as starting and ending
17457 Defaults to @samp{#t}.
17461 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
17462 Extra options to include.
17464 Defaults to @samp{()}.
17472 @deftypevr {@code{getmail-configuration} parameter} list idle
17473 A list of mailboxes that getmail should wait on the server for new mail
17474 notifications. This depends on the server supporting the IDLE
17477 Defaults to @samp{()}.
17481 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
17482 Environment variables to set for getmail.
17484 Defaults to @samp{()}.
17488 @subsubheading Mail Aliases Service
17490 @cindex email aliases
17491 @cindex aliases, for email addresses
17493 @deffn {Scheme Variable} mail-aliases-service-type
17494 This is the type of the service which provides @code{/etc/aliases},
17495 specifying how to deliver mail to users on this system.
17498 (service mail-aliases-service-type
17499 '(("postmaster" "bob")
17500 ("bob" "bob@@example.com" "bob@@example2.com")))
17504 The configuration for a @code{mail-aliases-service-type} service is an
17505 association list denoting how to deliver mail that comes to this
17506 system. Each entry is of the form @code{(alias addresses ...)}, with
17507 @code{alias} specifying the local alias and @code{addresses} specifying
17508 where to deliver this user's mail.
17510 The aliases aren't required to exist as users on the local system. In
17511 the above example, there doesn't need to be a @code{postmaster} entry in
17512 the @code{operating-system}'s @code{user-accounts} in order to deliver
17513 the @code{postmaster} mail to @code{bob} (which subsequently would
17514 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
17516 @subsubheading GNU Mailutils IMAP4 Daemon
17517 @cindex GNU Mailutils IMAP4 Daemon
17519 @deffn {Scheme Variable} imap4d-service-type
17520 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
17521 mailutils, GNU Mailutils Manual}), whose value should be an
17522 @code{imap4d-configuration} object as in this example:
17525 (service imap4d-service-type
17526 (imap4d-configuration
17527 (config-file (local-file "imap4d.conf"))))
17531 @deftp {Data Type} imap4d-configuration
17532 Data type representing the configuration of @command{imap4d}.
17535 @item @code{package} (default: @code{mailutils})
17536 The package that provides @command{imap4d}.
17538 @item @code{config-file} (default: @code{%default-imap4d-config-file})
17539 File-like object of the configuration file to use, by default it will listen
17540 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
17541 Mailutils Manual}, for details.
17546 @node Messaging Services
17547 @subsection Messaging Services
17552 The @code{(gnu services messaging)} module provides Guix service
17553 definitions for messaging services: currently only Prosody is supported.
17555 @subsubheading Prosody Service
17557 @deffn {Scheme Variable} prosody-service-type
17558 This is the type for the @uref{https://prosody.im, Prosody XMPP
17559 communication server}. Its value must be a @code{prosody-configuration}
17560 record as in this example:
17563 (service prosody-service-type
17564 (prosody-configuration
17565 (modules-enabled (cons "groups" "mam" %default-modules-enabled))
17568 (int-component-configuration
17569 (hostname "conference.example.net")
17571 (mod-muc (mod-muc-configuration)))))
17574 (virtualhost-configuration
17575 (domain "example.net"))))))
17578 See below for details about @code{prosody-configuration}.
17582 By default, Prosody does not need much configuration. Only one
17583 @code{virtualhosts} field is needed: it specifies the domain you wish
17586 You can perform various sanity checks on the generated configuration
17587 with the @code{prosodyctl check} command.
17589 Prosodyctl will also help you to import certificates from the
17590 @code{letsencrypt} directory so that the @code{prosody} user can access
17591 them. See @url{https://prosody.im/doc/letsencrypt}.
17594 prosodyctl --root cert import /etc/letsencrypt/live
17597 The available configuration parameters follow. Each parameter
17598 definition is preceded by its type; for example, @samp{string-list foo}
17599 indicates that the @code{foo} parameter should be specified as a list of
17600 strings. Types starting with @code{maybe-} denote parameters that won't
17601 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
17603 There is also a way to specify the configuration as a string, if you
17604 have an old @code{prosody.cfg.lua} file that you want to port over from
17605 some other system; see the end for more details.
17607 The @code{file-object} type designates either a file-like object
17608 (@pxref{G-Expressions, file-like objects}) or a file name.
17610 @c The following documentation was initially generated by
17611 @c (generate-documentation) in (gnu services messaging). Manually maintained
17612 @c documentation is better, so we shouldn't hesitate to edit below as
17613 @c needed. However if the change you want to make to this documentation
17614 @c can be done in an automated way, it's probably easier to change
17615 @c (generate-documentation) than to make it below and have to deal with
17616 @c the churn as Prosody updates.
17618 Available @code{prosody-configuration} fields are:
17620 @deftypevr {@code{prosody-configuration} parameter} package prosody
17621 The Prosody package.
17624 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
17625 Location of the Prosody data storage directory. See
17626 @url{https://prosody.im/doc/configure}.
17627 Defaults to @samp{"/var/lib/prosody"}.
17630 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
17631 Additional plugin directories. They are searched in all the specified
17632 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
17633 Defaults to @samp{()}.
17636 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
17637 Every virtual host and component needs a certificate so that clients and
17638 servers can securely verify its identity. Prosody will automatically load
17639 certificates/keys from the directory specified here.
17640 Defaults to @samp{"/etc/prosody/certs"}.
17643 @deftypevr {@code{prosody-configuration} parameter} string-list admins
17644 This is a list of accounts that are admins for the server. Note that you
17645 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
17646 @url{https://prosody.im/doc/creating_accounts}.
17647 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
17648 Defaults to @samp{()}.
17651 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
17652 Enable use of libevent for better performance under high load. See
17653 @url{https://prosody.im/doc/libevent}.
17654 Defaults to @samp{#f}.
17657 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
17658 This is the list of modules Prosody will load on startup. It looks for
17659 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
17660 Documentation on modules can be found at:
17661 @url{https://prosody.im/doc/modules}.
17662 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
17665 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
17666 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
17667 should you want to disable them then add them to this list.
17668 Defaults to @samp{()}.
17671 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
17672 Path to a text file where the shared groups are defined. If this path is
17673 empty then @samp{mod_groups} does nothing. See
17674 @url{https://prosody.im/doc/modules/mod_groups}.
17675 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
17678 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
17679 Disable account creation by default, for security. See
17680 @url{https://prosody.im/doc/creating_accounts}.
17681 Defaults to @samp{#f}.
17684 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
17685 These are the SSL/TLS-related settings. Most of them are disabled so to
17686 use Prosody's defaults. If you do not completely understand these options, do
17687 not add them to your config, it is easy to lower the security of your server
17688 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
17690 Available @code{ssl-configuration} fields are:
17692 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
17693 This determines what handshake to use.
17696 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
17697 Path to your private key file.
17700 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
17701 Path to your certificate file.
17704 @deftypevr {@code{ssl-configuration} parameter} file-object capath
17705 Path to directory containing root certificates that you wish Prosody to
17706 trust when verifying the certificates of remote servers.
17707 Defaults to @samp{"/etc/ssl/certs"}.
17710 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
17711 Path to a file containing root certificates that you wish Prosody to trust.
17712 Similar to @code{capath} but with all certificates concatenated together.
17715 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
17716 A list of verification options (these mostly map to OpenSSL's
17717 @code{set_verify()} flags).
17720 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
17721 A list of general options relating to SSL/TLS. These map to OpenSSL's
17722 @code{set_options()}. For a full list of options available in LuaSec, see the
17726 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
17727 How long a chain of certificate authorities to check when looking for a
17728 trusted root certificate.
17731 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
17732 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
17733 clients, and in what order.
17736 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
17737 A path to a file containing parameters for Diffie-Hellman key exchange. You
17738 can create such a file with:
17739 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
17742 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
17743 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
17744 @samp{"secp384r1"}.
17747 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
17748 A list of "extra" verification options.
17751 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
17752 Password for encrypted private keys.
17757 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
17758 Whether to force all client-to-server connections to be encrypted or not.
17759 See @url{https://prosody.im/doc/modules/mod_tls}.
17760 Defaults to @samp{#f}.
17763 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
17764 Set of mechanisms that will never be offered. See
17765 @url{https://prosody.im/doc/modules/mod_saslauth}.
17766 Defaults to @samp{("DIGEST-MD5")}.
17769 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
17770 Whether to force all server-to-server connections to be encrypted or not.
17771 See @url{https://prosody.im/doc/modules/mod_tls}.
17772 Defaults to @samp{#f}.
17775 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
17776 Whether to require encryption and certificate authentication. This
17777 provides ideal security, but requires servers you communicate with to support
17778 encryption AND present valid, trusted certificates. See
17779 @url{https://prosody.im/doc/s2s#security}.
17780 Defaults to @samp{#f}.
17783 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
17784 Many servers don't support encryption or have invalid or self-signed
17785 certificates. You can list domains here that will not be required to
17786 authenticate using certificates. They will be authenticated using DNS. See
17787 @url{https://prosody.im/doc/s2s#security}.
17788 Defaults to @samp{()}.
17791 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
17792 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
17793 valid certificates for some domains by specifying a list here. See
17794 @url{https://prosody.im/doc/s2s#security}.
17795 Defaults to @samp{()}.
17798 @deftypevr {@code{prosody-configuration} parameter} string authentication
17799 Select the authentication backend to use. The default provider stores
17800 passwords in plaintext and uses Prosody's configured data storage to store the
17801 authentication data. If you do not trust your server please see
17802 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
17803 about using the hashed backend. See also
17804 @url{https://prosody.im/doc/authentication}
17805 Defaults to @samp{"internal_plain"}.
17808 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
17809 Set logging options. Advanced logging configuration is not yet supported
17810 by the Prosody service. See @url{https://prosody.im/doc/logging}.
17811 Defaults to @samp{"*syslog"}.
17814 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
17815 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
17816 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
17819 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
17820 Maximum allowed size of the HTTP body (in bytes).
17823 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
17824 Some modules expose their own URL in various ways. This URL is built
17825 from the protocol, host and port used. If Prosody sits behind a proxy, the
17826 public URL will be @code{http-external-url} instead. See
17827 @url{https://prosody.im/doc/http#external_url}.
17830 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
17831 A host in Prosody is a domain on which user accounts can be created. For
17832 example if you want your users to have addresses like
17833 @samp{"john.smith@@example.com"} then you need to add a host
17834 @samp{"example.com"}. All options in this list will apply only to this host.
17836 Note: the name "virtual" host is used in configuration to avoid confusion with
17837 the actual physical host that Prosody is installed on. A single Prosody
17838 instance can serve many domains, each one defined as a VirtualHost entry in
17839 Prosody's configuration. Conversely a server that hosts a single domain would
17840 have just one VirtualHost entry.
17842 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
17844 Available @code{virtualhost-configuration} fields are:
17846 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:
17847 @deftypevr {@code{virtualhost-configuration} parameter} string domain
17848 Domain you wish Prosody to serve.
17853 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
17854 Components are extra services on a server which are available to clients,
17855 usually on a subdomain of the main server (such as
17856 @samp{"mycomponent.example.com"}). Example components might be chatroom
17857 servers, user directories, or gateways to other protocols.
17859 Internal components are implemented with Prosody-specific plugins. To add an
17860 internal component, you simply fill the hostname field, and the plugin you wish
17861 to use for the component.
17863 See @url{https://prosody.im/doc/components}.
17864 Defaults to @samp{()}.
17866 Available @code{int-component-configuration} fields are:
17868 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:
17869 @deftypevr {@code{int-component-configuration} parameter} string hostname
17870 Hostname of the component.
17873 @deftypevr {@code{int-component-configuration} parameter} string plugin
17874 Plugin you wish to use for the component.
17877 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
17878 Multi-user chat (MUC) is Prosody's module for allowing you to create
17879 hosted chatrooms/conferences for XMPP users.
17881 General information on setting up and using multi-user chatrooms can be found
17882 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
17883 which you should read if you are new to XMPP chatrooms.
17885 See also @url{https://prosody.im/doc/modules/mod_muc}.
17887 Available @code{mod-muc-configuration} fields are:
17889 @deftypevr {@code{mod-muc-configuration} parameter} string name
17890 The name to return in service discovery responses.
17891 Defaults to @samp{"Prosody Chatrooms"}.
17894 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
17895 If @samp{#t}, this will only allow admins to create new chatrooms.
17896 Otherwise anyone can create a room. The value @samp{"local"} restricts room
17897 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
17898 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
17899 restricts to service administrators only.
17900 Defaults to @samp{#f}.
17903 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
17904 Maximum number of history messages that will be sent to the member that has
17905 just joined the room.
17906 Defaults to @samp{20}.
17913 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
17914 External components use XEP-0114, which most standalone components
17915 support. To add an external component, you simply fill the hostname field. See
17916 @url{https://prosody.im/doc/components}.
17917 Defaults to @samp{()}.
17919 Available @code{ext-component-configuration} fields are:
17921 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:
17922 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
17923 Password which the component will use to log in.
17926 @deftypevr {@code{ext-component-configuration} parameter} string hostname
17927 Hostname of the component.
17932 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
17933 Port(s) Prosody listens on for component connections.
17934 Defaults to @samp{(5347)}.
17937 @deftypevr {@code{prosody-configuration} parameter} string component-interface
17938 Interface Prosody listens on for component connections.
17939 Defaults to @samp{"127.0.0.1"}.
17942 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
17943 Raw content that will be added to the configuration file.
17946 It could be that you just want to get a @code{prosody.cfg.lua}
17947 up and running. In that case, you can pass an
17948 @code{opaque-prosody-configuration} record as the value of
17949 @code{prosody-service-type}. As its name indicates, an opaque configuration
17950 does not have easy reflective capabilities.
17951 Available @code{opaque-prosody-configuration} fields are:
17953 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
17954 The prosody package.
17957 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
17958 The contents of the @code{prosody.cfg.lua} to use.
17961 For example, if your @code{prosody.cfg.lua} is just the empty
17962 string, you could instantiate a prosody service like this:
17965 (service prosody-service-type
17966 (opaque-prosody-configuration
17967 (prosody.cfg.lua "")))
17970 @c end of Prosody auto-generated documentation
17972 @subsubheading BitlBee Service
17974 @cindex IRC (Internet Relay Chat)
17975 @cindex IRC gateway
17976 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
17977 interface to a variety of messaging protocols such as XMPP.
17979 @defvr {Scheme Variable} bitlbee-service-type
17980 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
17981 gateway daemon. Its value is a @code{bitlbee-configuration} (see
17984 To have BitlBee listen on port 6667 on localhost, add this line to your
17988 (service bitlbee-service-type)
17992 @deftp {Data Type} bitlbee-configuration
17993 This is the configuration for BitlBee, with the following fields:
17996 @item @code{interface} (default: @code{"127.0.0.1"})
17997 @itemx @code{port} (default: @code{6667})
17998 Listen on the network interface corresponding to the IP address
17999 specified in @var{interface}, on @var{port}.
18001 When @var{interface} is @code{127.0.0.1}, only local clients can
18002 connect; when it is @code{0.0.0.0}, connections can come from any
18003 networking interface.
18005 @item @code{package} (default: @code{bitlbee})
18006 The BitlBee package to use.
18008 @item @code{plugins} (default: @code{'()})
18009 List of plugin packages to use---e.g., @code{bitlbee-discord}.
18011 @item @code{extra-settings} (default: @code{""})
18012 Configuration snippet added as-is to the BitlBee configuration file.
18016 @subsubheading Quassel Service
18018 @cindex IRC (Internet Relay Chat)
18019 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
18020 meaning that one or more clients can attach to and detach from the
18023 @defvr {Scheme Variable} quassel-service-type
18024 This is the service type for the @url{https://quassel-irc.org/,Quassel}
18025 IRC backend daemon. Its value is a @code{quassel-configuration}
18029 @deftp {Data Type} quassel-configuration
18030 This is the configuration for Quassel, with the following fields:
18033 @item @code{quassel} (default: @code{quassel})
18034 The Quassel package to use.
18036 @item @code{interface} (default: @code{"::,0.0.0.0"})
18037 @item @code{port} (default: @code{4242})
18038 Listen on the network interface(s) corresponding to the IPv4 or IPv6
18039 interfaces specified in the comma delimited @var{interface}, on
18042 @item @code{loglevel} (default: @code{"Info"})
18043 The level of logging desired. Accepted values are Debug, Info, Warning
18048 @node Telephony Services
18049 @subsection Telephony Services
18051 @cindex Murmur (VoIP server)
18052 @cindex VoIP server
18053 This section describes how to set up and run a Murmur server. Murmur is
18054 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
18057 @deftp {Data Type} murmur-configuration
18058 The service type for the Murmur server. An example configuration can
18062 (service murmur-service-type
18063 (murmur-configuration
18065 "Welcome to this Mumble server running on Guix!")
18066 (cert-required? #t) ;disallow text password logins
18067 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
18068 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
18071 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
18072 password with the command that is printed during the activation phase.
18074 It is recommended to register a normal Mumble user account
18075 and grant it admin or moderator rights.
18076 You can use the @code{mumble} client to
18077 login as new normal user, register yourself, and log out.
18078 For the next step login with the name @code{SuperUser} use
18079 the @code{SuperUser} password that you set previously,
18080 and grant your newly registered mumble user administrator or moderator
18081 rights and create some channels.
18083 Available @code{murmur-configuration} fields are:
18086 @item @code{package} (default: @code{mumble})
18087 Package that contains @code{bin/murmurd}.
18089 @item @code{user} (default: @code{"murmur"})
18090 User who will run the Murmur server.
18092 @item @code{group} (default: @code{"murmur"})
18093 Group of the user who will run the murmur server.
18095 @item @code{port} (default: @code{64738})
18096 Port on which the server will listen.
18098 @item @code{welcome-text} (default: @code{""})
18099 Welcome text sent to clients when they connect.
18101 @item @code{server-password} (default: @code{""})
18102 Password the clients have to enter in order to connect.
18104 @item @code{max-users} (default: @code{100})
18105 Maximum of users that can be connected to the server at once.
18107 @item @code{max-user-bandwidth} (default: @code{#f})
18108 Maximum voice traffic a user can send per second.
18110 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
18111 File name of the sqlite database.
18112 The service's user will become the owner of the directory.
18114 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
18115 File name of the log file.
18116 The service's user will become the owner of the directory.
18118 @item @code{autoban-attempts} (default: @code{10})
18119 Maximum number of logins a user can make in @code{autoban-timeframe}
18120 without getting auto banned for @code{autoban-time}.
18122 @item @code{autoban-timeframe} (default: @code{120})
18123 Timeframe for autoban in seconds.
18125 @item @code{autoban-time} (default: @code{300})
18126 Amount of time in seconds for which a client gets banned
18127 when violating the autoban limits.
18129 @item @code{opus-threshold} (default: @code{100})
18130 Percentage of clients that need to support opus
18131 before switching over to opus audio codec.
18133 @item @code{channel-nesting-limit} (default: @code{10})
18134 How deep channels can be nested at maximum.
18136 @item @code{channelname-regex} (default: @code{#f})
18137 A string in form of a Qt regular expression that channel names must conform to.
18139 @item @code{username-regex} (default: @code{#f})
18140 A string in form of a Qt regular expression that user names must conform to.
18142 @item @code{text-message-length} (default: @code{5000})
18143 Maximum size in bytes that a user can send in one text chat message.
18145 @item @code{image-message-length} (default: @code{(* 128 1024)})
18146 Maximum size in bytes that a user can send in one image message.
18148 @item @code{cert-required?} (default: @code{#f})
18149 If it is set to @code{#t} clients that use weak password authentication
18150 will not be accepted. Users must have completed the certificate wizard to join.
18152 @item @code{remember-channel?} (default: @code{#f})
18153 Should murmur remember the last channel each user was in when they disconnected
18154 and put them into the remembered channel when they rejoin.
18156 @item @code{allow-html?} (default: @code{#f})
18157 Should html be allowed in text messages, user comments, and channel descriptions.
18159 @item @code{allow-ping?} (default: @code{#f})
18160 Setting to true exposes the current user count, the maximum user count, and
18161 the server's maximum bandwidth per client to unauthenticated users. In the
18162 Mumble client, this information is shown in the Connect dialog.
18164 Disabling this setting will prevent public listing of the server.
18166 @item @code{bonjour?} (default: @code{#f})
18167 Should the server advertise itself in the local network through the bonjour protocol.
18169 @item @code{send-version?} (default: @code{#f})
18170 Should the murmur server version be exposed in ping requests.
18172 @item @code{log-days} (default: @code{31})
18173 Murmur also stores logs in the database, which are accessible via RPC.
18174 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
18175 or -1 to disable logging to the database.
18177 @item @code{obfuscate-ips?} (default: @code{#t})
18178 Should logged ips be obfuscated to protect the privacy of users.
18180 @item @code{ssl-cert} (default: @code{#f})
18181 File name of the SSL/TLS certificate used for encrypted connections.
18184 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
18186 @item @code{ssl-key} (default: @code{#f})
18187 Filepath to the ssl private key used for encrypted connections.
18189 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
18192 @item @code{ssl-dh-params} (default: @code{#f})
18193 File name of a PEM-encoded file with Diffie-Hellman parameters
18194 for the SSL/TLS encryption. Alternatively you set it to
18195 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
18196 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
18198 @item @code{ssl-ciphers} (default: @code{#f})
18199 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
18202 This option is specified using
18203 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
18204 OpenSSL cipher list notation}.
18206 It is recommended that you try your cipher string using 'openssl ciphers <string>'
18207 before setting it here, to get a feel for which cipher suites you will get.
18208 After setting this option, it is recommend that you inspect your Murmur log
18209 to ensure that Murmur is using the cipher suites that you expected it to.
18211 Note: Changing this option may impact the backwards compatibility of your
18212 Murmur server, and can remove the ability for older Mumble clients to be able
18215 @item @code{public-registration} (default: @code{#f})
18216 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
18218 You can optionally register your server in the public server list that the
18219 @code{mumble} client shows on startup.
18220 You cannot register your server if you have set a @code{server-password},
18221 or set @code{allow-ping} to @code{#f}.
18223 It might take a few hours until it shows up in the public list.
18225 @item @code{file} (default: @code{#f})
18226 Optional alternative override for this configuration.
18230 @deftp {Data Type} murmur-public-registration-configuration
18231 Configuration for public registration of a murmur service.
18235 This is a display name for your server. Not to be confused with the hostname.
18237 @item @code{password}
18238 A password to identify your registration.
18239 Subsequent updates will need the same password. Don't lose your password.
18242 This should be a @code{http://} or @code{https://} link to your web
18245 @item @code{hostname} (default: @code{#f})
18246 By default your server will be listed by its IP address.
18247 If it is set your server will be linked by this host name instead.
18253 @node Monitoring Services
18254 @subsection Monitoring Services
18256 @subsubheading Tailon Service
18258 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
18259 viewing and searching log files.
18261 The following example will configure the service with default values.
18262 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
18265 (service tailon-service-type)
18268 The following example customises more of the Tailon configuration,
18269 adding @command{sed} to the list of allowed commands.
18272 (service tailon-service-type
18273 (tailon-configuration
18275 (tailon-configuration-file
18276 (allowed-commands '("tail" "grep" "awk" "sed"))))))
18280 @deftp {Data Type} tailon-configuration
18281 Data type representing the configuration of Tailon.
18282 This type has the following parameters:
18285 @item @code{config-file} (default: @code{(tailon-configuration-file)})
18286 The configuration file to use for Tailon. This can be set to a
18287 @dfn{tailon-configuration-file} record value, or any gexp
18288 (@pxref{G-Expressions}).
18290 For example, to instead use a local file, the @code{local-file} function
18294 (service tailon-service-type
18295 (tailon-configuration
18296 (config-file (local-file "./my-tailon.conf"))))
18299 @item @code{package} (default: @code{tailon})
18300 The tailon package to use.
18305 @deftp {Data Type} tailon-configuration-file
18306 Data type representing the configuration options for Tailon.
18307 This type has the following parameters:
18310 @item @code{files} (default: @code{(list "/var/log")})
18311 List of files to display. The list can include strings for a single file
18312 or directory, or a list, where the first item is the name of a
18313 subsection, and the remaining items are the files or directories in that
18316 @item @code{bind} (default: @code{"localhost:8080"})
18317 Address and port to which Tailon should bind on.
18319 @item @code{relative-root} (default: @code{#f})
18320 URL path to use for Tailon, set to @code{#f} to not use a path.
18322 @item @code{allow-transfers?} (default: @code{#t})
18323 Allow downloading the log files in the web interface.
18325 @item @code{follow-names?} (default: @code{#t})
18326 Allow tailing of not-yet existent files.
18328 @item @code{tail-lines} (default: @code{200})
18329 Number of lines to read initially from each file.
18331 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
18332 Commands to allow running. By default, @code{sed} is disabled.
18334 @item @code{debug?} (default: @code{#f})
18335 Set @code{debug?} to @code{#t} to show debug messages.
18337 @item @code{wrap-lines} (default: @code{#t})
18338 Initial line wrapping state in the web interface. Set to @code{#t} to
18339 initially wrap lines (the default), or to @code{#f} to initially not
18342 @item @code{http-auth} (default: @code{#f})
18343 HTTP authentication type to use. Set to @code{#f} to disable
18344 authentication (the default). Supported values are @code{"digest"} or
18347 @item @code{users} (default: @code{#f})
18348 If HTTP authentication is enabled (see @code{http-auth}), access will be
18349 restricted to the credentials provided here. To configure users, use a
18350 list of pairs, where the first element of the pair is the username, and
18351 the 2nd element of the pair is the password.
18354 (tailon-configuration-file
18355 (http-auth "basic")
18356 (users '(("user1" . "password1")
18357 ("user2" . "password2"))))
18364 @subsubheading Darkstat Service
18366 Darkstat is a packet sniffer that captures network traffic, calculates
18367 statistics about usage, and serves reports over HTTP.
18369 @defvar {Scheme Variable} darkstat-service-type
18370 This is the service type for the
18371 @uref{https://unix4lyfe.org/darkstat/, darkstat}
18372 service, its value must be a @code{darkstat-configuration} record as in
18376 (service darkstat-service-type
18377 (darkstat-configuration
18378 (interface "eno1")))
18382 @deftp {Data Type} darkstat-configuration
18383 Data type representing the configuration of @command{darkstat}.
18386 @item @code{package} (default: @code{darkstat})
18387 The darkstat package to use.
18389 @item @code{interface}
18390 Capture traffic on the specified network interface.
18392 @item @code{port} (default: @code{"667"})
18393 Bind the web interface to the specified port.
18395 @item @code{bind-address} (default: @code{"127.0.0.1"})
18396 Bind the web interface to the specified address.
18398 @item @code{base} (default: @code{"/"})
18399 Specify the path of the base URL. This can be useful if
18400 @command{darkstat} is accessed via a reverse proxy.
18405 @subsubheading Prometheus Node Exporter Service
18407 @cindex prometheus-node-exporter
18408 The Prometheus ``node exporter'' makes hardware and operating system statistics
18409 provided by the Linux kernel available for the Prometheus monitoring system.
18410 This service should be deployed on all physical nodes and virtual machines,
18411 where monitoring these statistics is desirable.
18413 @defvar {Scheme variable} prometheus-node-exporter-service-type
18414 This is the service type for the
18415 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
18416 service, its value must be a @code{prometheus-node-exporter-configuration}
18417 record as in this example:
18420 (service prometheus-node-exporter-service-type
18421 (prometheus-node-exporter-configuration
18422 (web-listen-address ":9100")))
18426 @deftp {Data Type} prometheus-node-exporter-configuration
18427 Data type representing the configuration of @command{node_exporter}.
18430 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
18431 The prometheus-node-exporter package to use.
18433 @item @code{web-listen-address} (default: @code{":9100"})
18434 Bind the web interface to the specified address.
18439 @subsubheading Zabbix server
18440 @cindex zabbix zabbix-server
18441 Zabbix provides monitoring metrics, among others network utilization, CPU load
18442 and disk space consumption:
18445 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
18446 @item Auto-discovery of servers and network devices and interfaces.
18447 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
18448 @item Distributed monitoring with centralized web administration.
18449 @item Native high performance agents.
18450 @item SLA, and ITIL KPI metrics on reporting.
18451 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
18452 @item Remote command execution through Zabbix proxies.
18455 @c %start of fragment
18457 Available @code{zabbix-server-configuration} fields are:
18459 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
18460 The zabbix-server package.
18464 @deftypevr {@code{zabbix-server-configuration} parameter} string user
18465 User who will run the Zabbix server.
18467 Defaults to @samp{"zabbix"}.
18471 @deftypevr {@code{zabbix-server-configuration} parameter} group group
18472 Group who will run the Zabbix server.
18474 Defaults to @samp{"zabbix"}.
18478 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
18479 Database host name.
18481 Defaults to @samp{"127.0.0.1"}.
18485 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
18488 Defaults to @samp{"zabbix"}.
18492 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
18495 Defaults to @samp{"zabbix"}.
18499 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
18500 Database password. Please, use @code{include-files} with
18501 @code{DBPassword=SECRET} inside a specified file instead.
18503 Defaults to @samp{""}.
18507 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
18510 Defaults to @samp{5432}.
18514 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
18515 Specifies where log messages are written to:
18519 @code{system} - syslog.
18522 @code{file} - file specified with @code{log-file} parameter.
18525 @code{console} - standard output.
18529 Defaults to @samp{""}.
18533 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
18534 Log file name for @code{log-type} @code{file} parameter.
18536 Defaults to @samp{"/var/log/zabbix/server.log"}.
18540 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
18543 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
18547 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
18548 The location of certificate authority (CA) files for SSL server
18549 certificate verification.
18551 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
18555 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
18556 Location of SSL client certificates.
18558 Defaults to @samp{"/etc/ssl/certs"}.
18562 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
18563 Extra options will be appended to Zabbix server configuration file.
18565 Defaults to @samp{""}.
18569 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
18570 You may include individual files or all files in a directory in the
18571 configuration file.
18573 Defaults to @samp{()}.
18577 @c %end of fragment
18579 @subsubheading Zabbix agent
18580 @cindex zabbix zabbix-agent
18582 Zabbix agent gathers information for Zabbix server.
18584 @c %start of fragment
18586 Available @code{zabbix-agent-configuration} fields are:
18588 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
18589 The zabbix-agent package.
18593 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
18594 User who will run the Zabbix agent.
18596 Defaults to @samp{"zabbix"}.
18600 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
18601 Group who will run the Zabbix agent.
18603 Defaults to @samp{"zabbix"}.
18607 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
18608 Unique, case sensitive hostname which is required for active checks and
18609 must match hostname as configured on the server.
18611 Defaults to @samp{"Zabbix server"}.
18615 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
18616 Specifies where log messages are written to:
18620 @code{system} - syslog.
18623 @code{file} - file specified with @code{log-file} parameter.
18626 @code{console} - standard output.
18630 Defaults to @samp{""}.
18634 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
18635 Log file name for @code{log-type} @code{file} parameter.
18637 Defaults to @samp{"/var/log/zabbix/agent.log"}.
18641 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
18644 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
18648 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
18649 List of IP addresses, optionally in CIDR notation, or hostnames of
18650 Zabbix servers and Zabbix proxies. Incoming connections will be
18651 accepted only from the hosts listed here.
18653 Defaults to @samp{("127.0.0.1")}.
18657 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
18658 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
18659 proxies for active checks. If port is not specified, default port is
18660 used. If this parameter is not specified, active checks are disabled.
18662 Defaults to @samp{("127.0.0.1")}.
18666 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
18667 Extra options will be appended to Zabbix server configuration file.
18669 Defaults to @samp{""}.
18673 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
18674 You may include individual files or all files in a directory in the
18675 configuration file.
18677 Defaults to @samp{()}.
18681 @c %end of fragment
18683 @subsubheading Zabbix front-end
18684 @cindex zabbix zabbix-front-end
18686 This service provides a WEB interface to Zabbix server.
18688 @c %start of fragment
18690 Available @code{zabbix-front-end-configuration} fields are:
18692 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
18693 NGINX configuration.
18697 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
18698 Database host name.
18700 Defaults to @samp{"localhost"}.
18704 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
18707 Defaults to @samp{5432}.
18711 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
18714 Defaults to @samp{"zabbix"}.
18718 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
18721 Defaults to @samp{"zabbix"}.
18725 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
18726 Database password. Please, use @code{db-secret-file} instead.
18728 Defaults to @samp{""}.
18732 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
18733 Secret file which will be appended to @file{zabbix.conf.php} file. This
18734 file contains credentials for use by Zabbix front-end. You are expected
18735 to create it manually.
18737 Defaults to @samp{""}.
18741 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
18742 Zabbix server hostname.
18744 Defaults to @samp{"localhost"}.
18748 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
18749 Zabbix server port.
18751 Defaults to @samp{10051}.
18756 @c %end of fragment
18758 @node Kerberos Services
18759 @subsection Kerberos Services
18762 The @code{(gnu services kerberos)} module provides services relating to
18763 the authentication protocol @dfn{Kerberos}.
18765 @subsubheading Krb5 Service
18767 Programs using a Kerberos client library normally
18768 expect a configuration file in @file{/etc/krb5.conf}.
18769 This service generates such a file from a definition provided in the
18770 operating system declaration.
18771 It does not cause any daemon to be started.
18773 No ``keytab'' files are provided by this service---you must explicitly create them.
18774 This service is known to work with the MIT client library, @code{mit-krb5}.
18775 Other implementations have not been tested.
18777 @defvr {Scheme Variable} krb5-service-type
18778 A service type for Kerberos 5 clients.
18782 Here is an example of its use:
18784 (service krb5-service-type
18785 (krb5-configuration
18786 (default-realm "EXAMPLE.COM")
18787 (allow-weak-crypto? #t)
18790 (name "EXAMPLE.COM")
18791 (admin-server "groucho.example.com")
18792 (kdc "karl.example.com"))
18795 (admin-server "kerb-admin.argrx.edu")
18796 (kdc "keys.argrx.edu"))))))
18800 This example provides a Kerberos@tie{}5 client configuration which:
18802 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
18803 of which have distinct administration servers and key distribution centers;
18804 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
18805 specified by clients;
18806 @item Accepts services which only support encryption types known to be weak.
18809 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
18810 Only the most commonly used ones are described here.
18811 For a full list, and more detailed explanation of each, see the MIT
18812 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
18816 @deftp {Data Type} krb5-realm
18817 @cindex realm, kerberos
18820 This field is a string identifying the name of the realm.
18821 A common convention is to use the fully qualified DNS name of your organization,
18822 converted to upper case.
18824 @item @code{admin-server}
18825 This field is a string identifying the host where the administration server is
18829 This field is a string identifying the key distribution center
18834 @deftp {Data Type} krb5-configuration
18837 @item @code{allow-weak-crypto?} (default: @code{#f})
18838 If this flag is @code{#t} then services which only offer encryption algorithms
18839 known to be weak will be accepted.
18841 @item @code{default-realm} (default: @code{#f})
18842 This field should be a string identifying the default Kerberos
18843 realm for the client.
18844 You should set this field to the name of your Kerberos realm.
18845 If this value is @code{#f}
18846 then a realm must be specified with every Kerberos principal when invoking programs
18847 such as @command{kinit}.
18849 @item @code{realms}
18850 This should be a non-empty list of @code{krb5-realm} objects, which clients may
18852 Normally, one of them will have a @code{name} field matching the @code{default-realm}
18858 @subsubheading PAM krb5 Service
18861 The @code{pam-krb5} service allows for login authentication and password
18862 management via Kerberos.
18863 You will need this service if you want PAM enabled applications to authenticate
18864 users using Kerberos.
18866 @defvr {Scheme Variable} pam-krb5-service-type
18867 A service type for the Kerberos 5 PAM module.
18870 @deftp {Data Type} pam-krb5-configuration
18871 Data type representing the configuration of the Kerberos 5 PAM module.
18872 This type has the following parameters:
18874 @item @code{pam-krb5} (default: @code{pam-krb5})
18875 The pam-krb5 package to use.
18877 @item @code{minimum-uid} (default: @code{1000})
18878 The smallest user ID for which Kerberos authentications should be attempted.
18879 Local accounts with lower values will silently fail to authenticate.
18884 @node LDAP Services
18885 @subsection LDAP Services
18887 @cindex nslcd, LDAP service
18889 The @code{(gnu services authentication)} module provides the
18890 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
18891 server. In addition to configuring the service itself, you may want to add
18892 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
18893 Switch} for detailed information.
18895 Here is a simple operating system declaration with a default configuration of
18896 the @code{nslcd-service-type} and a Name Service Switch configuration that
18897 consults the @code{ldap} name service last:
18900 (use-service-modules authentication)
18901 (use-modules (gnu system nss))
18907 (service nslcd-service-type)
18908 (service dhcp-client-service-type)
18910 (name-service-switch
18911 (let ((services (list (name-service (name "db"))
18912 (name-service (name "files"))
18913 (name-service (name "ldap")))))
18914 (name-service-switch
18915 (inherit %mdns-host-lookup-nss)
18916 (password services)
18919 (netgroup services)
18920 (gshadow services)))))
18923 @c %start of generated documentation for nslcd-configuration
18925 Available @code{nslcd-configuration} fields are:
18927 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
18928 The @code{nss-pam-ldapd} package to use.
18932 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
18933 The number of threads to start that can handle requests and perform LDAP
18934 queries. Each thread opens a separate connection to the LDAP server.
18935 The default is to start 5 threads.
18937 Defaults to @samp{disabled}.
18941 @deftypevr {@code{nslcd-configuration} parameter} string uid
18942 This specifies the user id with which the daemon should be run.
18944 Defaults to @samp{"nslcd"}.
18948 @deftypevr {@code{nslcd-configuration} parameter} string gid
18949 This specifies the group id with which the daemon should be run.
18951 Defaults to @samp{"nslcd"}.
18955 @deftypevr {@code{nslcd-configuration} parameter} log-option log
18956 This option controls the way logging is done via a list containing
18957 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
18958 or "syslog", or an absolute file name. The LEVEL argument is optional
18959 and specifies the log level. The log level may be one of the following
18960 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
18961 messages with the specified log level or higher are logged.
18963 Defaults to @samp{("/var/log/nslcd" info)}.
18967 @deftypevr {@code{nslcd-configuration} parameter} list uri
18968 The list of LDAP server URIs. Normally, only the first server will be
18969 used with the following servers as fall-back.
18971 Defaults to @samp{("ldap://localhost:389/")}.
18975 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
18976 The version of the LDAP protocol to use. The default is to use the
18977 maximum version supported by the LDAP library.
18979 Defaults to @samp{disabled}.
18983 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
18984 Specifies the distinguished name with which to bind to the directory
18985 server for lookups. The default is to bind anonymously.
18987 Defaults to @samp{disabled}.
18991 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
18992 Specifies the credentials with which to bind. This option is only
18993 applicable when used with binddn.
18995 Defaults to @samp{disabled}.
18999 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
19000 Specifies the distinguished name to use when the root user tries to
19001 modify a user's password using the PAM module.
19003 Defaults to @samp{disabled}.
19007 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
19008 Specifies the credentials with which to bind if the root user tries to
19009 change a user's password. This option is only applicable when used with
19012 Defaults to @samp{disabled}.
19016 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
19017 Specifies the SASL mechanism to be used when performing SASL
19020 Defaults to @samp{disabled}.
19024 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
19025 Specifies the SASL realm to be used when performing SASL authentication.
19027 Defaults to @samp{disabled}.
19031 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
19032 Specifies the authentication identity to be used when performing SASL
19035 Defaults to @samp{disabled}.
19039 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
19040 Specifies the authorization identity to be used when performing SASL
19043 Defaults to @samp{disabled}.
19047 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
19048 Determines whether the LDAP server host name should be canonicalised. If
19049 this is enabled the LDAP library will do a reverse host name lookup. By
19050 default, it is left up to the LDAP library whether this check is
19053 Defaults to @samp{disabled}.
19057 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
19058 Set the name for the GSS-API Kerberos credentials cache.
19060 Defaults to @samp{disabled}.
19064 @deftypevr {@code{nslcd-configuration} parameter} string base
19065 The directory search base.
19067 Defaults to @samp{"dc=example,dc=com"}.
19071 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
19072 Specifies the search scope (subtree, onelevel, base or children). The
19073 default scope is subtree; base scope is almost never useful for name
19074 service lookups; children scope is not supported on all servers.
19076 Defaults to @samp{(subtree)}.
19080 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
19081 Specifies the policy for dereferencing aliases. The default policy is
19082 to never dereference aliases.
19084 Defaults to @samp{disabled}.
19088 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
19089 Specifies whether automatic referral chasing should be enabled. The
19090 default behaviour is to chase referrals.
19092 Defaults to @samp{disabled}.
19096 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
19097 This option allows for custom attributes to be looked up instead of the
19098 default RFC 2307 attributes. It is a list of maps, each consisting of
19099 the name of a map, the RFC 2307 attribute to match and the query
19100 expression for the attribute as it is available in the directory.
19102 Defaults to @samp{()}.
19106 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
19107 A list of filters consisting of the name of a map to which the filter
19108 applies and an LDAP search filter expression.
19110 Defaults to @samp{()}.
19114 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
19115 Specifies the time limit in seconds to use when connecting to the
19116 directory server. The default value is 10 seconds.
19118 Defaults to @samp{disabled}.
19122 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
19123 Specifies the time limit (in seconds) to wait for a response from the
19124 LDAP server. A value of zero, which is the default, is to wait
19125 indefinitely for searches to be completed.
19127 Defaults to @samp{disabled}.
19131 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
19132 Specifies the period if inactivity (in seconds) after which the con‐
19133 nection to the LDAP server will be closed. The default is not to time
19136 Defaults to @samp{disabled}.
19140 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
19141 Specifies the number of seconds to sleep when connecting to all LDAP
19142 servers fails. By default one second is waited between the first
19143 failure and the first retry.
19145 Defaults to @samp{disabled}.
19149 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
19150 Specifies the time after which the LDAP server is considered to be
19151 permanently unavailable. Once this time is reached retries will be done
19152 only once per this time period. The default value is 10 seconds.
19154 Defaults to @samp{disabled}.
19158 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
19159 Specifies whether to use SSL/TLS or not (the default is not to). If
19160 'start-tls is specified then StartTLS is used rather than raw LDAP over
19163 Defaults to @samp{disabled}.
19167 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
19168 Specifies what checks to perform on a server-supplied certificate. The
19169 meaning of the values is described in the ldap.conf(5) manual page.
19171 Defaults to @samp{disabled}.
19175 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
19176 Specifies the directory containing X.509 certificates for peer authen‐
19177 tication. This parameter is ignored when using GnuTLS.
19179 Defaults to @samp{disabled}.
19183 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
19184 Specifies the path to the X.509 certificate for peer authentication.
19186 Defaults to @samp{disabled}.
19190 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
19191 Specifies the path to an entropy source. This parameter is ignored when
19194 Defaults to @samp{disabled}.
19198 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
19199 Specifies the ciphers to use for TLS as a string.
19201 Defaults to @samp{disabled}.
19205 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
19206 Specifies the path to the file containing the local certificate for
19207 client TLS authentication.
19209 Defaults to @samp{disabled}.
19213 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
19214 Specifies the path to the file containing the private key for client TLS
19217 Defaults to @samp{disabled}.
19221 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
19222 Set this to a number greater than 0 to request paged results from the
19223 LDAP server in accordance with RFC2696. The default (0) is to not
19224 request paged results.
19226 Defaults to @samp{disabled}.
19230 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
19231 This option prevents group membership lookups through LDAP for the
19232 specified users. Alternatively, the value 'all-local may be used. With
19233 that value nslcd builds a full list of non-LDAP users on startup.
19235 Defaults to @samp{disabled}.
19239 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
19240 This option ensures that LDAP users with a numeric user id lower than
19241 the specified value are ignored.
19243 Defaults to @samp{disabled}.
19247 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
19248 This option specifies an offset that is added to all LDAP numeric user
19249 ids. This can be used to avoid user id collisions with local users.
19251 Defaults to @samp{disabled}.
19255 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
19256 This option specifies an offset that is added to all LDAP numeric group
19257 ids. This can be used to avoid user id collisions with local groups.
19259 Defaults to @samp{disabled}.
19263 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
19264 If this option is set, the member attribute of a group may point to
19265 another group. Members of nested groups are also returned in the higher
19266 level group and parent groups are returned when finding groups for a
19267 specific user. The default is not to perform extra searches for nested
19270 Defaults to @samp{disabled}.
19274 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
19275 If this option is set, the group member list is not retrieved when
19276 looking up groups. Lookups for finding which groups a user belongs to
19277 will remain functional so the user will likely still get the correct
19278 groups assigned on login.
19280 Defaults to @samp{disabled}.
19284 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
19285 If this option is set, functions which cause all user/group entries to
19286 be loaded from the directory will not succeed in doing so. This can
19287 dramatically reduce LDAP server load in situations where there are a
19288 great number of users and/or groups. This option is not recommended for
19289 most configurations.
19291 Defaults to @samp{disabled}.
19295 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
19296 This option can be used to specify how user and group names are verified
19297 within the system. This pattern is used to check all user and group
19298 names that are requested and returned from LDAP.
19300 Defaults to @samp{disabled}.
19304 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
19305 This specifies whether or not to perform searches using case-insensitive
19306 matching. Enabling this could open up the system to authorization
19307 bypass vulnerabilities and introduce nscd cache poisoning
19308 vulnerabilities which allow denial of service.
19310 Defaults to @samp{disabled}.
19314 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
19315 This option specifies whether password policy controls are requested and
19316 handled from the LDAP server when performing user authentication.
19318 Defaults to @samp{disabled}.
19322 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
19323 By default nslcd performs an LDAP search with the user's credentials
19324 after BIND (authentication) to ensure that the BIND operation was
19325 successful. The default search is a simple check to see if the user's
19326 DN exists. A search filter can be specified that will be used instead.
19327 It should return at least one entry.
19329 Defaults to @samp{disabled}.
19333 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
19334 This option allows flexible fine tuning of the authorisation check that
19335 should be performed. The search filter specified is executed and if any
19336 entries match, access is granted, otherwise access is denied.
19338 Defaults to @samp{disabled}.
19342 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
19343 If this option is set password modification using pam_ldap will be
19344 denied and the specified message will be presented to the user instead.
19345 The message can be used to direct the user to an alternative means of
19346 changing their password.
19348 Defaults to @samp{disabled}.
19352 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
19353 List of pam service names for which LDAP authentication should suffice.
19355 Defaults to @samp{()}.
19359 @c %end of generated documentation for nslcd-configuration
19363 @subsection Web Services
19368 The @code{(gnu services web)} module provides the Apache HTTP Server,
19369 the nginx web server, and also a fastcgi wrapper daemon.
19371 @subsubheading Apache HTTP Server
19373 @deffn {Scheme Variable} httpd-service-type
19374 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
19375 (@dfn{httpd}). The value for this service type is a
19376 @code{httpd-configuration} record.
19378 A simple example configuration is given below.
19381 (service httpd-service-type
19382 (httpd-configuration
19385 (server-name "www.example.com")
19386 (document-root "/srv/http/www.example.com")))))
19389 Other services can also extend the @code{httpd-service-type} to add to
19393 (simple-service 'my-extra-server httpd-service-type
19397 (list (string-append
19398 "ServerName "www.example.com
19399 DocumentRoot \"/srv/http/www.example.com\"")))))
19403 The details for the @code{httpd-configuration}, @code{httpd-module},
19404 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
19407 @deffn {Data Type} httpd-configuration
19408 This data type represents the configuration for the httpd service.
19411 @item @code{package} (default: @code{httpd})
19412 The httpd package to use.
19414 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19415 The pid file used by the shepherd-service.
19417 @item @code{config} (default: @code{(httpd-config-file)})
19418 The configuration file to use with the httpd service. The default value
19419 is a @code{httpd-config-file} record, but this can also be a different
19420 G-expression that generates a file, for example a @code{plain-file}. A
19421 file outside of the store can also be specified through a string.
19426 @deffn {Data Type} httpd-module
19427 This data type represents a module for the httpd service.
19431 The name of the module.
19434 The file for the module. This can be relative to the httpd package being
19435 used, the absolute location of a file, or a G-expression for a file
19436 within the store, for example @code{(file-append mod-wsgi
19437 "/modules/mod_wsgi.so")}.
19442 @defvr {Scheme Variable} %default-httpd-modules
19443 A default list of @code{httpd-module} objects.
19446 @deffn {Data Type} httpd-config-file
19447 This data type represents a configuration file for the httpd service.
19450 @item @code{modules} (default: @code{%default-httpd-modules})
19451 The modules to load. Additional modules can be added here, or loaded by
19452 additional configuration.
19454 For example, in order to handle requests for PHP files, you can use Apache’s
19455 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
19458 (service httpd-service-type
19459 (httpd-configuration
19464 (name "proxy_module")
19465 (file "modules/mod_proxy.so"))
19467 (name "proxy_fcgi_module")
19468 (file "modules/mod_proxy_fcgi.so"))
19469 %default-httpd-modules))
19470 (extra-config (list "\
19471 <FilesMatch \\.php$>
19472 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
19473 </FilesMatch>"))))))
19474 (service php-fpm-service-type
19475 (php-fpm-configuration
19476 (socket "/var/run/php-fpm.sock")
19477 (socket-group "httpd")))
19480 @item @code{server-root} (default: @code{httpd})
19481 The @code{ServerRoot} in the configuration file, defaults to the httpd
19482 package. Directives including @code{Include} and @code{LoadModule} are
19483 taken as relative to the server root.
19485 @item @code{server-name} (default: @code{#f})
19486 The @code{ServerName} in the configuration file, used to specify the
19487 request scheme, hostname and port that the server uses to identify
19490 This doesn't need to be set in the server config, and can be specifyed
19491 in virtual hosts. The default is @code{#f} to not specify a
19494 @item @code{document-root} (default: @code{"/srv/http"})
19495 The @code{DocumentRoot} from which files will be served.
19497 @item @code{listen} (default: @code{'("80")})
19498 The list of values for the @code{Listen} directives in the config
19499 file. The value should be a list of strings, when each string can
19500 specify the port number to listen on, and optionally the IP address and
19503 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19504 The @code{PidFile} to use. This should match the @code{pid-file} set in
19505 the @code{httpd-configuration} so that the Shepherd service is
19506 configured correctly.
19508 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
19509 The @code{ErrorLog} to which the server will log errors.
19511 @item @code{user} (default: @code{"httpd"})
19512 The @code{User} which the server will answer requests as.
19514 @item @code{group} (default: @code{"httpd"})
19515 The @code{Group} which the server will answer requests as.
19517 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
19518 A flat list of strings and G-expressions which will be added to the end
19519 of the configuration file.
19521 Any values which the service is extended with will be appended to this
19527 @deffn {Data Type} httpd-virtualhost
19528 This data type represents a virtualhost configuration block for the httpd service.
19530 These should be added to the extra-config for the httpd-service.
19533 (simple-service 'my-extra-server httpd-service-type
19537 (list (string-append
19538 "ServerName "www.example.com
19539 DocumentRoot \"/srv/http/www.example.com\"")))))
19543 @item @code{addresses-and-ports}
19544 The addresses and ports for the @code{VirtualHost} directive.
19546 @item @code{contents}
19547 The contents of the @code{VirtualHost} directive, this should be a list
19548 of strings and G-expressions.
19553 @subsubheading NGINX
19555 @deffn {Scheme Variable} nginx-service-type
19556 Service type for the @uref{https://nginx.org/,NGinx} web server. The
19557 value for this service type is a @code{<nginx-configuration>} record.
19559 A simple example configuration is given below.
19562 (service nginx-service-type
19563 (nginx-configuration
19565 (list (nginx-server-configuration
19566 (server-name '("www.example.com"))
19567 (root "/srv/http/www.example.com"))))))
19570 In addition to adding server blocks to the service configuration
19571 directly, this service can be extended by other services to add server
19572 blocks, as in this example:
19575 (simple-service 'my-extra-server nginx-service-type
19576 (list (nginx-server-configuration
19577 (root "/srv/http/extra-website")
19578 (try-files (list "$uri" "$uri/index.html")))))
19582 At startup, @command{nginx} has not yet read its configuration file, so
19583 it uses a default file to log error messages. If it fails to load its
19584 configuration file, that is where error messages are logged. After the
19585 configuration file is loaded, the default error log file changes as per
19586 configuration. In our case, startup error messages can be found in
19587 @file{/var/run/nginx/logs/error.log}, and after configuration in
19588 @file{/var/log/nginx/error.log}. The second location can be changed
19589 with the @var{log-directory} configuration option.
19591 @deffn {Data Type} nginx-configuration
19592 This data type represents the configuration for NGinx. Some
19593 configuration can be done through this and the other provided record
19594 types, or alternatively, a config file can be provided.
19597 @item @code{nginx} (default: @code{nginx})
19598 The nginx package to use.
19600 @item @code{log-directory} (default: @code{"/var/log/nginx"})
19601 The directory to which NGinx will write log files.
19603 @item @code{run-directory} (default: @code{"/var/run/nginx"})
19604 The directory in which NGinx will create a pid file, and write temporary
19607 @item @code{server-blocks} (default: @code{'()})
19608 A list of @dfn{server blocks} to create in the generated configuration
19609 file, the elements should be of type
19610 @code{<nginx-server-configuration>}.
19612 The following example would setup NGinx to serve @code{www.example.com}
19613 from the @code{/srv/http/www.example.com} directory, without using
19616 (service nginx-service-type
19617 (nginx-configuration
19619 (list (nginx-server-configuration
19620 (server-name '("www.example.com"))
19621 (root "/srv/http/www.example.com"))))))
19624 @item @code{upstream-blocks} (default: @code{'()})
19625 A list of @dfn{upstream blocks} to create in the generated configuration
19626 file, the elements should be of type
19627 @code{<nginx-upstream-configuration>}.
19629 Configuring upstreams through the @code{upstream-blocks} can be useful
19630 when combined with @code{locations} in the
19631 @code{<nginx-server-configuration>} records. The following example
19632 creates a server configuration with one location configuration, that
19633 will proxy requests to a upstream configuration, which will handle
19634 requests with two servers.
19639 (nginx-configuration
19641 (list (nginx-server-configuration
19642 (server-name '("www.example.com"))
19643 (root "/srv/http/www.example.com")
19646 (nginx-location-configuration
19648 (body '("proxy_pass http://server-proxy;"))))))))
19650 (list (nginx-upstream-configuration
19651 (name "server-proxy")
19652 (servers (list "server1.example.com"
19653 "server2.example.com")))))))
19656 @item @code{file} (default: @code{#f})
19657 If a configuration @var{file} is provided, this will be used, rather than
19658 generating a configuration file from the provided @code{log-directory},
19659 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
19660 proper operation, these arguments should match what is in @var{file} to ensure
19661 that the directories are created when the service is activated.
19663 This can be useful if you have an existing configuration file, or it's
19664 not possible to do what is required through the other parts of the
19665 nginx-configuration record.
19667 @item @code{server-names-hash-bucket-size} (default: @code{#f})
19668 Bucket size for the server names hash tables, defaults to @code{#f} to
19669 use the size of the processors cache line.
19671 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
19672 Maximum bucket size for the server names hash tables.
19674 @item @code{extra-content} (default: @code{""})
19675 Extra content for the @code{http} block. Should be string or a string
19676 valued G-expression.
19681 @deftp {Data Type} nginx-server-configuration
19682 Data type representing the configuration of an nginx server block.
19683 This type has the following parameters:
19686 @item @code{listen} (default: @code{'("80" "443 ssl")})
19687 Each @code{listen} directive sets the address and port for IP, or the
19688 path for a UNIX-domain socket on which the server will accept requests.
19689 Both address and port, or only address or only port can be specified.
19690 An address may also be a hostname, for example:
19693 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
19696 @item @code{server-name} (default: @code{(list 'default)})
19697 A list of server names this server represents. @code{'default} represents the
19698 default server for connections matching no other server.
19700 @item @code{root} (default: @code{"/srv/http"})
19701 Root of the website nginx will serve.
19703 @item @code{locations} (default: @code{'()})
19704 A list of @dfn{nginx-location-configuration} or
19705 @dfn{nginx-named-location-configuration} records to use within this
19708 @item @code{index} (default: @code{(list "index.html")})
19709 Index files to look for when clients ask for a directory. If it cannot be found,
19710 Nginx will send the list of files in the directory.
19712 @item @code{try-files} (default: @code{'()})
19713 A list of files whose existence is checked in the specified order.
19714 @code{nginx} will use the first file it finds to process the request.
19716 @item @code{ssl-certificate} (default: @code{#f})
19717 Where to find the certificate for secure connections. Set it to @code{#f} if
19718 you don't have a certificate or you don't want to use HTTPS.
19720 @item @code{ssl-certificate-key} (default: @code{#f})
19721 Where to find the private key for secure connections. Set it to @code{#f} if
19722 you don't have a key or you don't want to use HTTPS.
19724 @item @code{server-tokens?} (default: @code{#f})
19725 Whether the server should add its configuration to response.
19727 @item @code{raw-content} (default: @code{'()})
19728 A list of raw lines added to the server block.
19733 @deftp {Data Type} nginx-upstream-configuration
19734 Data type representing the configuration of an nginx @code{upstream}
19735 block. This type has the following parameters:
19739 Name for this group of servers.
19741 @item @code{servers}
19742 Specify the addresses of the servers in the group. The address can be
19743 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
19744 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
19745 prefix @samp{unix:}. For addresses using an IP address or domain name,
19746 the default port is 80, and a different port can be specified
19752 @deftp {Data Type} nginx-location-configuration
19753 Data type representing the configuration of an nginx @code{location}
19754 block. This type has the following parameters:
19758 URI which this location block matches.
19760 @anchor{nginx-location-configuration body}
19762 Body of the location block, specified as a list of strings. This can contain
19764 configuration directives. For example, to pass requests to a upstream
19765 server group defined using an @code{nginx-upstream-configuration} block,
19766 the following directive would be specified in the body @samp{(list "proxy_pass
19767 http://upstream-name;")}.
19772 @deftp {Data Type} nginx-named-location-configuration
19773 Data type representing the configuration of an nginx named location
19774 block. Named location blocks are used for request redirection, and not
19775 used for regular request processing. This type has the following
19780 Name to identify this location block.
19783 @xref{nginx-location-configuration body}, as the body for named location
19784 blocks can be used in a similar way to the
19785 @code{nginx-location-configuration body}. One restriction is that the
19786 body of a named location block cannot contain location blocks.
19791 @subsubheading Varnish Cache
19793 Varnish is a fast cache server that sits in between web applications
19794 and end users. It proxies requests from clients and caches the
19795 accessed URLs such that multiple requests for the same resource only
19796 creates one request to the back-end.
19798 @defvr {Scheme Variable} varnish-service-type
19799 Service type for the Varnish daemon.
19802 @deftp {Data Type} varnish-configuration
19803 Data type representing the @code{varnish} service configuration.
19804 This type has the following parameters:
19807 @item @code{package} (default: @code{varnish})
19808 The Varnish package to use.
19810 @item @code{name} (default: @code{"default"})
19811 A name for this Varnish instance. Varnish will create a directory in
19812 @file{/var/varnish/} with this name and keep temporary files there. If
19813 the name starts with a forward slash, it is interpreted as an absolute
19816 Pass the @code{-n} argument to other Varnish programs to connect to the
19817 named instance, e.g.@: @command{varnishncsa -n default}.
19819 @item @code{backend} (default: @code{"localhost:8080"})
19820 The backend to use. This option has no effect if @code{vcl} is set.
19822 @item @code{vcl} (default: #f)
19823 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
19824 is @code{#f}, Varnish will proxy @code{backend} using the default
19825 configuration. Otherwise this must be a file-like object with valid
19828 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
19829 For example, to mirror @url{http://www.gnu.org,www.gnu.org} with VCL you
19830 can do something along these lines:
19833 (define %gnu-mirror
19834 (plain-file "gnu.vcl"
19836 backend gnu @{ .host = \"www.gnu.org\"; @}"))
19840 (services (cons (service varnish-service-type
19841 (varnish-configuration
19843 (vcl %gnu-mirror)))
19847 The configuration of an already running Varnish instance can be inspected
19848 and changed using the @command{varnishadm} program.
19850 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
19851 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
19852 comprehensive documentation on Varnish and its configuration language.
19854 @item @code{listen} (default: @code{'("localhost:80")})
19855 List of addresses Varnish will listen on.
19857 @item @code{storage} (default: @code{'("malloc,128m")})
19858 List of storage backends that will be available in VCL.
19860 @item @code{parameters} (default: @code{'()})
19861 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
19863 @item @code{extra-options} (default: @code{'()})
19864 Additional arguments to pass to the @command{varnishd} process.
19869 @subsubheading Patchwork
19871 Patchwork is a patch tracking system. It can collect patches sent to a
19872 mailing list, and display them in a web interface.
19874 @defvr {Scheme Variable} patchwork-service-type
19875 Service type for Patchwork.
19878 The following example is an example of a minimal service for Patchwork, for
19879 the @code{patchwork.example.com} domain.
19882 (service patchwork-service-type
19883 (patchwork-configuration
19884 (domain "patchwork.example.com")
19886 (patchwork-settings-module
19887 (allowed-hosts (list domain))
19888 (default-from-email "patchwork@@patchwork.example.com")))
19889 (getmail-retriever-config
19890 (getmail-retriever-configuration
19891 (type "SimpleIMAPSSLRetriever")
19892 (server "imap.example.com")
19894 (username "patchwork")
19896 (list (file-append coreutils "/bin/cat")
19897 "/etc/getmail-patchwork-imap-password"))
19899 '((mailboxes . ("Patches"))))))))
19903 There are three records for configuring the Patchwork service. The
19904 @code{<patchwork-configuration>} relates to the configuration for Patchwork
19905 within the HTTPD service.
19907 The @code{settings-module} field within the @code{<patchwork-configuration>}
19908 record can be populated with the @code{<patchwork-settings-module>} record,
19909 which describes a settings module that is generated within the Guix store.
19911 For the @code{database-configuration} field within the
19912 @code{<patchwork-settings-module>}, the
19913 @code{<patchwork-database-configuration>} must be used.
19915 @deftp {Data Type} patchwork-configuration
19916 Data type representing the Patchwork service configuration. This type has the
19917 following parameters:
19920 @item @code{patchwork} (default: @code{patchwork})
19921 The Patchwork package to use.
19923 @item @code{domain}
19924 The domain to use for Patchwork, this is used in the HTTPD service virtual
19927 @item @code{settings-module}
19928 The settings module to use for Patchwork. As a Django application, Patchwork
19929 is configured with a Python module containing the settings. This can either be
19930 an instance of the @code{<patchwork-settings-module>} record, any other record
19931 that represents the settings in the store, or a directory outside of the
19934 @item @code{static-path} (default: @code{"/static/"})
19935 The path under which the HTTPD service should serve the static files.
19937 @item @code{getmail-retriever-config}
19938 The getmail-retriever-configuration record value to use with
19939 Patchwork. Getmail will be configured with this value, the messages will be
19940 delivered to Patchwork.
19945 @deftp {Data Type} patchwork-settings-module
19946 Data type representing a settings module for Patchwork. Some of these
19947 settings relate directly to Patchwork, but others relate to Django, the web
19948 framework used by Patchwork, or the Django Rest Framework library. This type
19949 has the following parameters:
19952 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
19953 The database connection settings used for Patchwork. See the
19954 @code{<patchwork-database-configuration>} record type for more information.
19956 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
19957 Patchwork, as a Django web application uses a secret key for cryptographically
19958 signing values. This file should contain a unique unpredictable value.
19960 If this file does not exist, it will be created and populated with a random
19961 value by the patchwork-setup shepherd service.
19963 This setting relates to Django.
19965 @item @code{allowed-hosts}
19966 A list of valid hosts for this Patchwork service. This should at least include
19967 the domain specified in the @code{<patchwork-configuration>} record.
19969 This is a Django setting.
19971 @item @code{default-from-email}
19972 The email address from which Patchwork should send email by default.
19974 This is a Patchwork setting.
19976 @item @code{static-url} (default: @code{#f})
19977 The URL to use when serving static assets. It can be part of a URL, or a full
19978 URL, but must end in a @code{/}.
19980 If the default value is used, the @code{static-path} value from the
19981 @code{<patchwork-configuration>} record will be used.
19983 This is a Django setting.
19985 @item @code{admins} (default: @code{'()})
19986 Email addresses to send the details of errors that occur. Each value should
19987 be a list containing two elements, the name and then the email address.
19989 This is a Django setting.
19991 @item @code{debug?} (default: @code{#f})
19992 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
19993 messages will be shown.
19995 This is a Django setting.
19997 @item @code{enable-rest-api?} (default: @code{#t})
19998 Whether to enable the Patchwork REST API.
20000 This is a Patchwork setting.
20002 @item @code{enable-xmlrpc?} (default: @code{#t})
20003 Whether to enable the XML RPC API.
20005 This is a Patchwork setting.
20007 @item @code{force-https-links?} (default: @code{#t})
20008 Whether to use HTTPS links on Patchwork pages.
20010 This is a Patchwork setting.
20012 @item @code{extra-settings} (default: @code{""})
20013 Extra code to place at the end of the Patchwork settings module.
20018 @deftp {Data Type} patchwork-database-configuration
20019 Data type representing the database configuration for Patchwork.
20022 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
20023 The database engine to use.
20025 @item @code{name} (default: @code{"patchwork"})
20026 The name of the database to use.
20028 @item @code{user} (default: @code{"httpd"})
20029 The user to connect to the database as.
20031 @item @code{password} (default: @code{""})
20032 The password to use when connecting to the database.
20034 @item @code{host} (default: @code{""})
20035 The host to make the database connection to.
20037 @item @code{port} (default: @code{""})
20038 The port on which to connect to the database.
20043 @subsubheading FastCGI
20046 FastCGI is an interface between the front-end and the back-end of a web
20047 service. It is a somewhat legacy facility; new web services should
20048 generally just talk HTTP between the front-end and the back-end.
20049 However there are a number of back-end services such as PHP or the
20050 optimized HTTP Git repository access that use FastCGI, so we have
20051 support for it in Guix.
20053 To use FastCGI, you configure the front-end web server (e.g., nginx) to
20054 dispatch some subset of its requests to the fastcgi backend, which
20055 listens on a local TCP or UNIX socket. There is an intermediary
20056 @code{fcgiwrap} program that sits between the actual backend process and
20057 the web server. The front-end indicates which backend program to run,
20058 passing that information to the @code{fcgiwrap} process.
20060 @defvr {Scheme Variable} fcgiwrap-service-type
20061 A service type for the @code{fcgiwrap} FastCGI proxy.
20064 @deftp {Data Type} fcgiwrap-configuration
20065 Data type representing the configuration of the @code{fcgiwrap} service.
20066 This type has the following parameters:
20068 @item @code{package} (default: @code{fcgiwrap})
20069 The fcgiwrap package to use.
20071 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
20072 The socket on which the @code{fcgiwrap} process should listen, as a
20073 string. Valid @var{socket} values include
20074 @code{unix:@var{/path/to/unix/socket}},
20075 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
20076 @code{tcp6:[@var{ipv6_addr}]:port}.
20078 @item @code{user} (default: @code{fcgiwrap})
20079 @itemx @code{group} (default: @code{fcgiwrap})
20080 The user and group names, as strings, under which to run the
20081 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
20082 the user asks for the specific user or group names @code{fcgiwrap} that
20083 the corresponding user and/or group is present on the system.
20085 It is possible to configure a FastCGI-backed web service to pass HTTP
20086 authentication information from the front-end to the back-end, and to
20087 allow @code{fcgiwrap} to run the back-end process as a corresponding
20088 local user. To enable this capability on the back-end., run
20089 @code{fcgiwrap} as the @code{root} user and group. Note that this
20090 capability also has to be configured on the front-end as well.
20095 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
20096 with some additional features useful for sites of any size.
20098 These features include:
20100 @item Adaptive process spawning
20101 @item Basic statistics (similar to Apache's mod_status)
20102 @item Advanced process management with graceful stop/start
20103 @item Ability to start workers with different uid/gid/chroot/environment
20104 and different php.ini (replaces safe_mode)
20105 @item Stdout & stderr logging
20106 @item Emergency restart in case of accidental opcode cache destruction
20107 @item Accelerated upload support
20108 @item Support for a "slowlog"
20109 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
20110 a special function to finish request & flush all data while continuing to do
20111 something time-consuming (video converting, stats processing, etc.)
20113 ...@: and much more.
20115 @defvr {Scheme Variable} php-fpm-service-type
20116 A Service type for @code{php-fpm}.
20119 @deftp {Data Type} php-fpm-configuration
20120 Data Type for php-fpm service configuration.
20122 @item @code{php} (default: @code{php})
20123 The php package to use.
20124 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
20125 The address on which to accept FastCGI requests. Valid syntaxes are:
20127 @item @code{"ip.add.re.ss:port"}
20128 Listen on a TCP socket to a specific address on a specific port.
20129 @item @code{"port"}
20130 Listen on a TCP socket to all addresses on a specific port.
20131 @item @code{"/path/to/unix/socket"}
20132 Listen on a unix socket.
20135 @item @code{user} (default: @code{php-fpm})
20136 User who will own the php worker processes.
20137 @item @code{group} (default: @code{php-fpm})
20138 Group of the worker processes.
20139 @item @code{socket-user} (default: @code{php-fpm})
20140 User who can speak to the php-fpm socket.
20141 @item @code{socket-group} (default: @code{php-fpm})
20142 Group that can speak to the php-fpm socket.
20143 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
20144 The process id of the php-fpm process is written to this file
20145 once the service has started.
20146 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
20147 Log for the php-fpm master process.
20148 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
20149 Detailed settings for the php-fpm process manager.
20152 @item @code{<php-fpm-dynamic-process-manager-configuration>}
20153 @item @code{<php-fpm-static-process-manager-configuration>}
20154 @item @code{<php-fpm-on-demand-process-manager-configuration>}
20156 @item @code{display-errors} (default @code{#f})
20157 Determines whether php errors and warning should be sent to clients
20158 and displayed in their browsers.
20159 This is useful for local php development, but a security risk for public sites,
20160 as error messages can reveal passwords and personal data.
20161 @item @code{timezone} (default @code{#f})
20162 Specifies @code{php_admin_value[date.timezone]} parameter.
20163 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
20164 This file will log the @code{stderr} outputs of php worker processes.
20165 Can be set to @code{#f} to disable logging.
20166 @item @code{file} (default @code{#f})
20167 An optional override of the whole configuration.
20168 You can use the @code{mixed-text-file} function or an absolute filepath for it.
20172 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
20173 Data Type for the @code{dynamic} php-fpm process manager. With the
20174 @code{dynamic} process manager, spare worker processes are kept around
20175 based on it's configured limits.
20177 @item @code{max-children} (default: @code{5})
20178 Maximum of worker processes.
20179 @item @code{start-servers} (default: @code{2})
20180 How many worker processes should be started on start-up.
20181 @item @code{min-spare-servers} (default: @code{1})
20182 How many spare worker processes should be kept around at minimum.
20183 @item @code{max-spare-servers} (default: @code{3})
20184 How many spare worker processes should be kept around at maximum.
20188 @deftp {Data type} php-fpm-static-process-manager-configuration
20189 Data Type for the @code{static} php-fpm process manager. With the
20190 @code{static} process manager, an unchanging number of worker processes
20193 @item @code{max-children} (default: @code{5})
20194 Maximum of worker processes.
20198 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
20199 Data Type for the @code{on-demand} php-fpm process manager. With the
20200 @code{on-demand} process manager, worker processes are only created as
20203 @item @code{max-children} (default: @code{5})
20204 Maximum of worker processes.
20205 @item @code{process-idle-timeout} (default: @code{10})
20206 The time in seconds after which a process with no requests is killed.
20211 @deffn {Scheme Procedure} nginx-php-fpm-location @
20212 [#:nginx-package nginx] @
20213 [socket (string-append "/var/run/php" @
20214 (version-major (package-version php)) @
20216 A helper function to quickly add php to an @code{nginx-server-configuration}.
20219 A simple services setup for nginx with php can look like this:
20221 (services (cons* (service dhcp-client-service-type)
20222 (service php-fpm-service-type)
20223 (service nginx-service-type
20224 (nginx-server-configuration
20225 (server-name '("example.com"))
20226 (root "/srv/http/")
20228 (list (nginx-php-location)))
20230 (ssl-certificate #f)
20231 (ssl-certificate-key #f)))
20235 @cindex cat-avatar-generator
20236 The cat avatar generator is a simple service to demonstrate the use of php-fpm
20237 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
20238 the hash of a user's email address.
20240 @deffn {Scheme Procedure} cat-avatar-generator-service @
20241 [#:cache-dir "/var/cache/cat-avatar-generator"] @
20242 [#:package cat-avatar-generator] @
20243 [#:configuration (nginx-server-configuration)]
20244 Returns an nginx-server-configuration that inherits @code{configuration}. It
20245 extends the nginx configuration to add a server block that serves @code{package},
20246 a version of cat-avatar-generator. During execution, cat-avatar-generator will
20247 be able to use @code{cache-dir} as its cache directory.
20250 A simple setup for cat-avatar-generator can look like this:
20252 (services (cons* (cat-avatar-generator-service
20254 (nginx-server-configuration
20255 (server-name '("example.com"))))
20260 @subsubheading Hpcguix-web
20262 @cindex hpcguix-web
20263 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
20264 program is a customizable web interface to browse Guix packages,
20265 initially designed for users of high-performance computing (HPC)
20268 @defvr {Scheme Variable} hpcguix-web-service-type
20269 The service type for @code{hpcguix-web}.
20272 @deftp {Data Type} hpcguix-web-configuration
20273 Data type for the hpcguix-web service configuration.
20277 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
20278 configuration. The main items available in this spec are:
20281 @item @code{title-prefix} (default: @code{"hpcguix | "})
20282 The page title prefix.
20284 @item @code{guix-command} (default: @code{"guix"})
20285 The @command{guix} command.
20287 @item @code{package-filter-proc} (default: @code{(const #t)})
20288 A procedure specifying how to filter packages that are displayed.
20290 @item @code{package-page-extension-proc} (default: @code{(const '())})
20291 Extension package for @code{hpcguix-web}.
20293 @item @code{menu} (default: @code{'()})
20294 Additional entry in page @code{menu}.
20296 @item @code{channels} (default: @code{%default-channels})
20297 List of channels from which the package list is built (@pxref{Channels}).
20299 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
20300 The expiration time, in seconds, after which the package list is rebuilt from
20301 the latest instances of the given channels.
20304 See the hpcguix-web repository for a
20305 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
20308 @item @code{package} (default: @code{hpcguix-web})
20309 The hpcguix-web package to use.
20313 A typical hpcguix-web service declaration looks like this:
20316 (service hpcguix-web-service-type
20317 (hpcguix-web-configuration
20319 #~(define site-config
20320 (hpcweb-configuration
20321 (title-prefix "Guix-HPC - ")
20322 (menu '(("/about" "ABOUT"))))))))
20326 The hpcguix-web service periodically updates the package list it publishes by
20327 pulling channels from Git. To that end, it needs to access X.509 certificates
20328 so that it can authenticate Git servers when communicating over HTTPS, and it
20329 assumes that @file{/etc/ssl/certs} contains those certificates.
20331 Thus, make sure to add @code{nss-certs} or another certificate package to the
20332 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
20333 more information on X.509 certificates.
20336 @node Certificate Services
20337 @subsection Certificate Services
20340 @cindex HTTP, HTTPS
20341 @cindex Let's Encrypt
20342 @cindex TLS certificates
20343 The @code{(gnu services certbot)} module provides a service to
20344 automatically obtain a valid TLS certificate from the Let's Encrypt
20345 certificate authority. These certificates can then be used to serve
20346 content securely over HTTPS or other TLS-based protocols, with the
20347 knowledge that the client will be able to verify the server's
20350 @url{https://letsencrypt.org/, Let's Encrypt} provides the
20351 @code{certbot} tool to automate the certification process. This tool
20352 first securely generates a key on the server. It then makes a request
20353 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
20354 checks that the request originates from the host in question by using a
20355 challenge-response protocol, requiring the server to provide its
20356 response over HTTP. If that protocol completes successfully, the CA
20357 signs the key, resulting in a certificate. That certificate is valid
20358 for a limited period of time, and therefore to continue to provide TLS
20359 services, the server needs to periodically ask the CA to renew its
20362 The certbot service automates this process: the initial key
20363 generation, the initial certification request to the Let's Encrypt
20364 service, the web server challenge/response integration, writing the
20365 certificate to disk, the automated periodic renewals, and the deployment
20366 tasks associated with the renewal (e.g.@: reloading services, copying keys
20367 with different permissions).
20369 Certbot is run twice a day, at a random minute within the hour. It
20370 won't do anything until your certificates are due for renewal or
20371 revoked, but running it regularly would give your service a chance of
20372 staying online in case a Let's Encrypt-initiated revocation happened for
20375 By using this service, you agree to the ACME Subscriber Agreement, which
20376 can be found there:
20377 @url{https://acme-v01.api.letsencrypt.org/directory}.
20379 @defvr {Scheme Variable} certbot-service-type
20380 A service type for the @code{certbot} Let's Encrypt client. Its value
20381 must be a @code{certbot-configuration} record as in this example:
20384 (define %nginx-deploy-hook
20386 "nginx-deploy-hook"
20387 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
20388 (kill pid SIGHUP))))
20390 (service certbot-service-type
20391 (certbot-configuration
20392 (email "foo@@example.net")
20395 (certificate-configuration
20396 (domains '("example.net" "www.example.net"))
20397 (deploy-hook %nginx-deploy-hook))
20398 (certificate-configuration
20399 (domains '("bar.example.net")))))))
20402 See below for details about @code{certbot-configuration}.
20405 @deftp {Data Type} certbot-configuration
20406 Data type representing the configuration of the @code{certbot} service.
20407 This type has the following parameters:
20410 @item @code{package} (default: @code{certbot})
20411 The certbot package to use.
20413 @item @code{webroot} (default: @code{/var/www})
20414 The directory from which to serve the Let's Encrypt challenge/response
20417 @item @code{certificates} (default: @code{()})
20418 A list of @code{certificates-configuration}s for which to generate
20419 certificates and request signatures. Each certificate has a @code{name}
20420 and several @code{domains}.
20423 Mandatory email used for registration, recovery contact, and important
20424 account notifications.
20426 @item @code{rsa-key-size} (default: @code{2048})
20427 Size of the RSA key.
20429 @item @code{default-location} (default: @i{see below})
20430 The default @code{nginx-location-configuration}. Because @code{certbot}
20431 needs to be able to serve challenges and responses, it needs to be able
20432 to run a web server. It does so by extending the @code{nginx} web
20433 service with an @code{nginx-server-configuration} listening on the
20434 @var{domains} on port 80, and which has a
20435 @code{nginx-location-configuration} for the @code{/.well-known/} URI
20436 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
20437 these nginx configuration data types.
20439 Requests to other URL paths will be matched by the
20440 @code{default-location}, which if present is added to all
20441 @code{nginx-server-configuration}s.
20443 By default, the @code{default-location} will issue a redirect from
20444 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
20445 you to define what to serve on your site via @code{https}.
20447 Pass @code{#f} to not issue a default location.
20451 @deftp {Data Type} certificate-configuration
20452 Data type representing the configuration of a certificate.
20453 This type has the following parameters:
20456 @item @code{name} (default: @i{see below})
20457 This name is used by Certbot for housekeeping and in file paths; it
20458 doesn't affect the content of the certificate itself. To see
20459 certificate names, run @code{certbot certificates}.
20461 Its default is the first provided domain.
20463 @item @code{domains} (default: @code{()})
20464 The first domain provided will be the subject CN of the certificate, and
20465 all domains will be Subject Alternative Names on the certificate.
20467 @item @code{challenge} (default: @code{#f})
20468 The challenge type that has to be run by certbot. If @code{#f} is specified,
20469 default to the HTTP challenge. If a value is specified, defaults to the
20470 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
20471 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
20472 and gives Let's Encrypt permission to log the public IP address of the
20473 requesting machine.
20475 @item @code{authentication-hook} (default: @code{#f})
20476 Command to be run in a shell once for each certificate challenge to be
20477 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
20478 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
20479 contains the validation string and @code{$CERTBOT_TOKEN} contains the
20480 file name of the resource requested when performing an HTTP-01 challenge.
20482 @item @code{cleanup-hook} (default: @code{#f})
20483 Command to be run in a shell once for each certificate challenge that
20484 have been answered by the @code{auth-hook}. For this command, the shell
20485 variables available in the @code{auth-hook} script are still available, and
20486 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
20487 of the @code{auth-hook} script.
20489 @item @code{deploy-hook} (default: @code{#f})
20490 Command to be run in a shell once for each successfully issued
20491 certificate. For this command, the shell variable
20492 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
20493 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
20494 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
20495 contain a space-delimited list of renewed certificate domains (for
20496 example, @samp{"example.com www.example.com"}.
20501 For each @code{certificate-configuration}, the certificate is saved to
20502 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
20503 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
20505 @subsection DNS Services
20506 @cindex DNS (domain name system)
20507 @cindex domain name system (DNS)
20509 The @code{(gnu services dns)} module provides services related to the
20510 @dfn{domain name system} (DNS). It provides a server service for hosting
20511 an @emph{authoritative} DNS server for multiple zones, slave or master.
20512 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
20513 caching and forwarding DNS server for the LAN, which uses
20514 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
20516 @subsubheading Knot Service
20518 An example configuration of an authoritative server for two zones, one master
20522 (define-zone-entries example.org.zone
20523 ;; Name TTL Class Type Data
20524 ("@@" "" "IN" "A" "127.0.0.1")
20525 ("@@" "" "IN" "NS" "ns")
20526 ("ns" "" "IN" "A" "127.0.0.1"))
20528 (define master-zone
20529 (knot-zone-configuration
20530 (domain "example.org")
20532 (origin "example.org")
20533 (entries example.org.zone)))))
20536 (knot-zone-configuration
20537 (domain "plop.org")
20538 (dnssec-policy "default")
20539 (master (list "plop-master"))))
20541 (define plop-master
20542 (knot-remote-configuration
20544 (address (list "208.76.58.171"))))
20548 (services (cons* (service knot-service-type
20549 (knot-configuration
20550 (remotes (list plop-master))
20551 (zones (list master-zone slave-zone))))
20556 @deffn {Scheme Variable} knot-service-type
20557 This is the type for the Knot DNS server.
20559 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
20560 zones, that is to say domain names you would buy from a registrar. This server
20561 is not a resolver, meaning that it can only resolve names for which it is
20562 authoritative. This server can be configured to serve zones as a master server
20563 or a slave server as a per-zone basis. Slave zones will get their data from
20564 masters, and will serve it as an authoritative server. From the point of view
20565 of a resolver, there is no difference between master and slave.
20567 The following data types are used to configure the Knot DNS server:
20570 @deftp {Data Type} knot-key-configuration
20571 Data type representing a key.
20572 This type has the following parameters:
20575 @item @code{id} (default: @code{""})
20576 An identifier for other configuration fields to refer to this key. IDs must
20577 be unique and must not be empty.
20579 @item @code{algorithm} (default: @code{#f})
20580 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
20581 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
20582 and @code{'hmac-sha512}.
20584 @item @code{secret} (default: @code{""})
20585 The secret key itself.
20590 @deftp {Data Type} knot-acl-configuration
20591 Data type representing an Access Control List (ACL) configuration.
20592 This type has the following parameters:
20595 @item @code{id} (default: @code{""})
20596 An identifier for ether configuration fields to refer to this key. IDs must be
20597 unique and must not be empty.
20599 @item @code{address} (default: @code{'()})
20600 An ordered list of IP addresses, network subnets, or network ranges represented
20601 with strings. The query must match one of them. Empty value means that
20602 address match is not required.
20604 @item @code{key} (default: @code{'()})
20605 An ordered list of references to keys represented with strings. The string
20606 must match a key ID defined in a @code{knot-key-configuration}. No key means
20607 that a key is not require to match that ACL.
20609 @item @code{action} (default: @code{'()})
20610 An ordered list of actions that are permitted or forbidden by this ACL. Possible
20611 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
20612 and @code{'update}.
20614 @item @code{deny?} (default: @code{#f})
20615 When true, the ACL defines restrictions. Listed actions are forbidden. When
20616 false, listed actions are allowed.
20621 @deftp {Data Type} zone-entry
20622 Data type represnting a record entry in a zone file.
20623 This type has the following parameters:
20626 @item @code{name} (default: @code{"@@"})
20627 The name of the record. @code{"@@"} refers to the origin of the zone. Names
20628 are relative to the origin of the zone. For example, in the @code{example.org}
20629 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
20630 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
20631 refers to @code{ns.example.org}.
20633 @item @code{ttl} (default: @code{""})
20634 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
20636 @item @code{class} (default: @code{"IN"})
20637 The class of the record. Knot currently supports only @code{"IN"} and
20638 partially @code{"CH"}.
20640 @item @code{type} (default: @code{"A"})
20641 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
20642 address), NS (Name Server) and MX (Mail eXchange). Many other types are
20645 @item @code{data} (default: @code{""})
20646 The data contained in the record. For instance an IP address associated with
20647 an A record, or a domain name associated with an NS record. Remember that
20648 domain names are relative to the origin unless they end with a dot.
20653 @deftp {Data Type} zone-file
20654 Data type representing the content of a zone file.
20655 This type has the following parameters:
20658 @item @code{entries} (default: @code{'()})
20659 The list of entries. The SOA record is taken care of, so you don't need to
20660 put it in the list of entries. This list should probably contain an entry
20661 for your primary authoritative DNS server. Other than using a list of entries
20662 directly, you can use @code{define-zone-entries} to define a object containing
20663 the list of entries more easily, that you can later pass to the @code{entries}
20664 field of the @code{zone-file}.
20666 @item @code{origin} (default: @code{""})
20667 The name of your zone. This parameter cannot be empty.
20669 @item @code{ns} (default: @code{"ns"})
20670 The domain of your primary authoritative DNS server. The name is relative to
20671 the origin, unless it ends with a dot. It is mandatory that this primary
20672 DNS server corresponds to an NS record in the zone and that it is associated
20673 to an IP address in the list of entries.
20675 @item @code{mail} (default: @code{"hostmaster"})
20676 An email address people can contact you at, as the owner of the zone. This
20677 is translated as @code{<mail>@@<origin>}.
20679 @item @code{serial} (default: @code{1})
20680 The serial number of the zone. As this is used to keep track of changes by
20681 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
20682 Always increment it when you make a change in your zone.
20684 @item @code{refresh} (default: @code{(* 2 24 3600)})
20685 The frequency at which slaves will do a zone transfer. This value is a number
20686 of seconds. It can be computed by multiplications or with
20687 @code{(string->duration)}.
20689 @item @code{retry} (default: @code{(* 15 60)})
20690 The period after which a slave will retry to contact its master when it fails
20691 to do so a first time.
20693 @item @code{expiry} (default: @code{(* 14 24 3600)})
20694 Default TTL of records. Existing records are considered correct for at most
20695 this amount of time. After this period, resolvers will invalidate their cache
20696 and check again that it still exists.
20698 @item @code{nx} (default: @code{3600})
20699 Default TTL of inexistant records. This delay is usually short because you want
20700 your new domains to reach everyone quickly.
20705 @deftp {Data Type} knot-remote-configuration
20706 Data type representing a remote configuration.
20707 This type has the following parameters:
20710 @item @code{id} (default: @code{""})
20711 An identifier for other configuration fields to refer to this remote. IDs must
20712 be unique and must not be empty.
20714 @item @code{address} (default: @code{'()})
20715 An ordered list of destination IP addresses. Addresses are tried in sequence.
20716 An optional port can be given with the @@ separator. For instance:
20717 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
20719 @item @code{via} (default: @code{'()})
20720 An ordered list of source IP addresses. An empty list will have Knot choose
20721 an appropriate source IP. An optional port can be given with the @@ separator.
20722 The default is to choose at random.
20724 @item @code{key} (default: @code{#f})
20725 A reference to a key, that is a string containing the identifier of a key
20726 defined in a @code{knot-key-configuration} field.
20731 @deftp {Data Type} knot-keystore-configuration
20732 Data type representing a keystore to hold dnssec keys.
20733 This type has the following parameters:
20736 @item @code{id} (default: @code{""})
20737 The id of the keystore. It must not be empty.
20739 @item @code{backend} (default: @code{'pem})
20740 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
20742 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
20743 The configuration string of the backend. An example for the PKCS#11 is:
20744 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
20745 For the pem backend, the string reprensents a path in the file system.
20750 @deftp {Data Type} knot-policy-configuration
20751 Data type representing a dnssec policy. Knot DNS is able to automatically
20752 sign your zones. It can either generate and manage your keys automatically or
20753 use keys that you generate.
20755 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
20756 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
20757 zone. In order to be trusted, the KSK needs to be present in the parent zone
20758 (usually a top-level domain). If your registrar supports dnssec, you will
20759 have to send them your KSK's hash so they can add a DS record in their zone.
20760 This is not automated and need to be done each time you change your KSK.
20762 The policy also defines the lifetime of keys. Usually, ZSK can be changed
20763 easily and use weaker cryptographic functions (they use lower parameters) in
20764 order to sign records quickly, so they are changed often. The KSK however
20765 requires manual interaction with the registrar, so they are changed less often
20766 and use stronger parameters because they sign only one record.
20768 This type has the following parameters:
20771 @item @code{id} (default: @code{""})
20772 The id of the policy. It must not be empty.
20774 @item @code{keystore} (default: @code{"default"})
20775 A reference to a keystore, that is a string containing the identifier of a
20776 keystore defined in a @code{knot-keystore-configuration} field. The
20777 @code{"default"} identifier means the default keystore (a kasp database that
20778 was setup by this service).
20780 @item @code{manual?} (default: @code{#f})
20781 Whether the key management is manual or automatic.
20783 @item @code{single-type-signing?} (default: @code{#f})
20784 When @code{#t}, use the Single-Type Signing Scheme.
20786 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
20787 An algorithm of signing keys and issued signatures.
20789 @item @code{ksk-size} (default: @code{256})
20790 The length of the KSK. Note that this value is correct for the default
20791 algorithm, but would be unsecure for other algorithms.
20793 @item @code{zsk-size} (default: @code{256})
20794 The length of the ZSK. Note that this value is correct for the default
20795 algorithm, but would be unsecure for other algorithms.
20797 @item @code{dnskey-ttl} (default: @code{'default})
20798 The TTL value for DNSKEY records added into zone apex. The special
20799 @code{'default} value means same as the zone SOA TTL.
20801 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
20802 The period between ZSK publication and the next rollover initiation.
20804 @item @code{propagation-delay} (default: @code{(* 24 3600)})
20805 An extra delay added for each key rollover step. This value should be high
20806 enough to cover propagation of data from the master server to all slaves.
20808 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
20809 A validity period of newly issued signatures.
20811 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
20812 A period how long before a signature expiration the signature will be refreshed.
20814 @item @code{nsec3?} (default: @code{#f})
20815 When @code{#t}, NSEC3 will be used instead of NSEC.
20817 @item @code{nsec3-iterations} (default: @code{5})
20818 The number of additional times the hashing is performed.
20820 @item @code{nsec3-salt-length} (default: @code{8})
20821 The length of a salt field in octets, which is appended to the original owner
20822 name before hashing.
20824 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
20825 The validity period of newly issued salt field.
20830 @deftp {Data Type} knot-zone-configuration
20831 Data type representing a zone served by Knot.
20832 This type has the following parameters:
20835 @item @code{domain} (default: @code{""})
20836 The domain served by this configuration. It must not be empty.
20838 @item @code{file} (default: @code{""})
20839 The file where this zone is saved. This parameter is ignored by master zones.
20840 Empty means default location that depends on the domain name.
20842 @item @code{zone} (default: @code{(zone-file)})
20843 The content of the zone file. This parameter is ignored by slave zones. It
20844 must contain a zone-file record.
20846 @item @code{master} (default: @code{'()})
20847 A list of master remotes. When empty, this zone is a master. When set, this
20848 zone is a slave. This is a list of remotes identifiers.
20850 @item @code{ddns-master} (default: @code{#f})
20851 The main master. When empty, it defaults to the first master in the list of
20854 @item @code{notify} (default: @code{'()})
20855 A list of slave remote identifiers.
20857 @item @code{acl} (default: @code{'()})
20858 A list of acl identifiers.
20860 @item @code{semantic-checks?} (default: @code{#f})
20861 When set, this adds more semantic checks to the zone.
20863 @item @code{disable-any?} (default: @code{#f})
20864 When set, this forbids queries of the ANY type.
20866 @item @code{zonefile-sync} (default: @code{0})
20867 The delay between a modification in memory and on disk. 0 means immediate
20870 @item @code{zonefile-load} (default: @code{#f})
20871 The way the zone file contents are applied during zone load. Possible values
20875 @item @code{#f} for using the default value from Knot,
20876 @item @code{'none} for not using the zone file at all,
20877 @item @code{'difference} for computing the difference between already available
20878 contents and zone contents and applying it to the current zone contents,
20879 @item @code{'difference-no-serial} for the same as @code{'difference}, but
20880 ignoring the SOA serial in the zone file, while the server takes care of it
20882 @item @code{'whole} for loading zone contents from the zone file.
20885 @item @code{journal-content} (default: @code{#f})
20886 The way the journal is used to store zone and its changes. Possible values
20887 are @code{'none} to not use it at all, @code{'changes} to store changes and
20888 @code{'all} to store contents. @code{#f} does not set this option, so the
20889 default value from Knot is used.
20891 @item @code{max-journal-usage} (default: @code{#f})
20892 The maximum size for the journal on disk. @code{#f} does not set this option,
20893 so the default value from Knot is used.
20895 @item @code{max-journal-depth} (default: @code{#f})
20896 The maximum size of the history. @code{#f} does not set this option, so the
20897 default value from Knot is used.
20899 @item @code{max-zone-size} (default: @code{#f})
20900 The maximum size of the zone file. This limit is enforced for incoming
20901 transfer and updates. @code{#f} does not set this option, so the default
20902 value from Knot is used.
20904 @item @code{dnssec-policy} (default: @code{#f})
20905 A reference to a @code{knot-policy-configuration} record, or the special
20906 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
20909 @item @code{serial-policy} (default: @code{'increment})
20910 A policy between @code{'increment} and @code{'unixtime}.
20915 @deftp {Data Type} knot-configuration
20916 Data type representing the Knot configuration.
20917 This type has the following parameters:
20920 @item @code{knot} (default: @code{knot})
20923 @item @code{run-directory} (default: @code{"/var/run/knot"})
20924 The run directory. This directory will be used for pid file and sockets.
20926 @item @code{includes} (default: @code{'()})
20927 A list of strings or file-like objects denoting other files that must be
20928 included at the top of the configuration file.
20930 @cindex secrets, Knot service
20931 This can be used to manage secrets out-of-band. For example, secret
20932 keys may be stored in an out-of-band file not managed by Guix, and
20933 thus not visible in @file{/gnu/store}---e.g., you could store secret
20934 key configuration in @file{/etc/knot/secrets.conf} and add this file
20935 to the @code{includes} list.
20937 One can generate a secret tsig key (for nsupdate and zone transfers with the
20938 keymgr command from the knot package. Note that the package is not automatically
20939 installed by the service. The following example shows how to generate a new
20943 keymgr -t mysecret > /etc/knot/secrets.conf
20944 chmod 600 /etc/knot/secrets.conf
20947 Also note that the generated key will be named @var{mysecret}, so it is the
20948 name that needs to be used in the @var{key} field of the
20949 @code{knot-acl-configuration} record and in other places that need to refer
20952 It can also be used to add configuration not supported by this interface.
20954 @item @code{listen-v4} (default: @code{"0.0.0.0"})
20955 An ip address on which to listen.
20957 @item @code{listen-v6} (default: @code{"::"})
20958 An ip address on which to listen.
20960 @item @code{listen-port} (default: @code{53})
20961 A port on which to listen.
20963 @item @code{keys} (default: @code{'()})
20964 The list of knot-key-configuration used by this configuration.
20966 @item @code{acls} (default: @code{'()})
20967 The list of knot-acl-configuration used by this configuration.
20969 @item @code{remotes} (default: @code{'()})
20970 The list of knot-remote-configuration used by this configuration.
20972 @item @code{zones} (default: @code{'()})
20973 The list of knot-zone-configuration used by this configuration.
20978 @subsubheading Dnsmasq Service
20980 @deffn {Scheme Variable} dnsmasq-service-type
20981 This is the type of the dnsmasq service, whose value should be an
20982 @code{dnsmasq-configuration} object as in this example:
20985 (service dnsmasq-service-type
20986 (dnsmasq-configuration
20988 (servers '("192.168.1.1"))))
20992 @deftp {Data Type} dnsmasq-configuration
20993 Data type representing the configuration of dnsmasq.
20996 @item @code{package} (default: @var{dnsmasq})
20997 Package object of the dnsmasq server.
20999 @item @code{no-hosts?} (default: @code{#f})
21000 When true, don't read the hostnames in /etc/hosts.
21002 @item @code{port} (default: @code{53})
21003 The port to listen on. Setting this to zero completely disables DNS
21004 responses, leaving only DHCP and/or TFTP functions.
21006 @item @code{local-service?} (default: @code{#t})
21007 Accept DNS queries only from hosts whose address is on a local subnet,
21008 ie a subnet for which an interface exists on the server.
21010 @item @code{listen-addresses} (default: @code{'()})
21011 Listen on the given IP addresses.
21013 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
21014 The file to read the IP address of the upstream nameservers from.
21016 @item @code{no-resolv?} (default: @code{#f})
21017 When true, don't read @var{resolv-file}.
21019 @item @code{servers} (default: @code{'()})
21020 Specify IP address of upstream servers directly.
21022 @item @code{cache-size} (default: @code{150})
21023 Set the size of dnsmasq's cache. Setting the cache size to zero
21026 @item @code{negative-cache?} (default: @code{#t})
21027 When false, disable negative caching.
21032 @subsubheading ddclient Service
21035 The ddclient service described below runs the ddclient daemon, which takes
21036 care of automatically updating DNS entries for service providers such as
21037 @uref{https://dyn.com/dns/, Dyn}.
21039 The following example show instantiates the service with its default
21043 (service ddclient-service-type)
21046 Note that ddclient needs to access credentials that are stored in a
21047 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
21048 @code{secret-file} below.) You are expected to create this file manually, in
21049 an ``out-of-band'' fashion (you @emph{could} make this file part of the
21050 service configuration, for instance by using @code{plain-file}, but it will be
21051 world-readable @i{via} @file{/gnu/store}.) See the examples in the
21052 @file{share/ddclient} directory of the @code{ddclient} package.
21054 @c %start of fragment
21056 Available @code{ddclient-configuration} fields are:
21058 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
21059 The ddclient package.
21063 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
21064 The period after which ddclient will retry to check IP and domain name.
21066 Defaults to @samp{300}.
21070 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
21071 Use syslog for the output.
21073 Defaults to @samp{#t}.
21077 @deftypevr {@code{ddclient-configuration} parameter} string mail
21080 Defaults to @samp{"root"}.
21084 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
21085 Mail failed update to user.
21087 Defaults to @samp{"root"}.
21091 @deftypevr {@code{ddclient-configuration} parameter} string pid
21092 The ddclient PID file.
21094 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
21098 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
21099 Enable SSL support.
21101 Defaults to @samp{#t}.
21105 @deftypevr {@code{ddclient-configuration} parameter} string user
21106 Specifies the user name or ID that is used when running ddclient
21109 Defaults to @samp{"ddclient"}.
21113 @deftypevr {@code{ddclient-configuration} parameter} string group
21114 Group of the user who will run the ddclient program.
21116 Defaults to @samp{"ddclient"}.
21120 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
21121 Secret file which will be appended to @file{ddclient.conf} file. This
21122 file contains credentials for use by ddclient. You are expected to
21123 create it manually.
21125 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
21129 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
21130 Extra options will be appended to @file{ddclient.conf} file.
21132 Defaults to @samp{()}.
21137 @c %end of fragment
21141 @subsection VPN Services
21142 @cindex VPN (virtual private network)
21143 @cindex virtual private network (VPN)
21145 The @code{(gnu services vpn)} module provides services related to
21146 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
21147 your machine to connect to a VPN, and a @emph{server} service for your machine
21148 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
21150 @deffn {Scheme Procedure} openvpn-client-service @
21151 [#:config (openvpn-client-configuration)]
21153 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
21156 @deffn {Scheme Procedure} openvpn-server-service @
21157 [#:config (openvpn-server-configuration)]
21159 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
21161 Both can be run simultaneously.
21164 @c %automatically generated documentation
21166 Available @code{openvpn-client-configuration} fields are:
21168 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
21169 The OpenVPN package.
21173 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
21174 The OpenVPN pid file.
21176 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21180 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
21181 The protocol (UDP or TCP) used to open a channel between clients and
21184 Defaults to @samp{udp}.
21188 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
21189 The device type used to represent the VPN connection.
21191 Defaults to @samp{tun}.
21195 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
21196 The certificate authority to check connections against.
21198 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21202 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
21203 The certificate of the machine the daemon is running on. It should be
21204 signed by the authority given in @code{ca}.
21206 Defaults to @samp{"/etc/openvpn/client.crt"}.
21210 @deftypevr {@code{openvpn-client-configuration} parameter} string key
21211 The key of the machine the daemon is running on. It must be the key whose
21212 certificate is @code{cert}.
21214 Defaults to @samp{"/etc/openvpn/client.key"}.
21218 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
21219 Whether to use the lzo compression algorithm.
21221 Defaults to @samp{#t}.
21225 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
21226 Don't re-read key files across SIGUSR1 or --ping-restart.
21228 Defaults to @samp{#t}.
21232 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
21233 Don't close and reopen TUN/TAP device or run up/down scripts across
21234 SIGUSR1 or --ping-restart restarts.
21236 Defaults to @samp{#t}.
21240 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
21243 Defaults to @samp{3}.
21247 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
21248 Add an additional layer of HMAC authentication on top of the TLS control
21249 channel to protect against DoS attacks.
21251 Defaults to @samp{#f}.
21255 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
21256 Whether to check the server certificate has server usage extension.
21258 Defaults to @samp{#t}.
21262 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
21263 Bind to a specific local port number.
21265 Defaults to @samp{#f}.
21269 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
21270 Retry resolving server address.
21272 Defaults to @samp{#t}.
21276 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
21277 A list of remote servers to connect to.
21279 Defaults to @samp{()}.
21281 Available @code{openvpn-remote-configuration} fields are:
21283 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
21286 Defaults to @samp{"my-server"}.
21290 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
21291 Port number the server listens to.
21293 Defaults to @samp{1194}.
21298 @c %end of automatic openvpn-client documentation
21300 @c %automatically generated documentation
21302 Available @code{openvpn-server-configuration} fields are:
21304 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
21305 The OpenVPN package.
21309 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
21310 The OpenVPN pid file.
21312 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21316 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
21317 The protocol (UDP or TCP) used to open a channel between clients and
21320 Defaults to @samp{udp}.
21324 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
21325 The device type used to represent the VPN connection.
21327 Defaults to @samp{tun}.
21331 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
21332 The certificate authority to check connections against.
21334 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21338 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
21339 The certificate of the machine the daemon is running on. It should be
21340 signed by the authority given in @code{ca}.
21342 Defaults to @samp{"/etc/openvpn/client.crt"}.
21346 @deftypevr {@code{openvpn-server-configuration} parameter} string key
21347 The key of the machine the daemon is running on. It must be the key whose
21348 certificate is @code{cert}.
21350 Defaults to @samp{"/etc/openvpn/client.key"}.
21354 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
21355 Whether to use the lzo compression algorithm.
21357 Defaults to @samp{#t}.
21361 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
21362 Don't re-read key files across SIGUSR1 or --ping-restart.
21364 Defaults to @samp{#t}.
21368 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
21369 Don't close and reopen TUN/TAP device or run up/down scripts across
21370 SIGUSR1 or --ping-restart restarts.
21372 Defaults to @samp{#t}.
21376 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
21379 Defaults to @samp{3}.
21383 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
21384 Add an additional layer of HMAC authentication on top of the TLS control
21385 channel to protect against DoS attacks.
21387 Defaults to @samp{#f}.
21391 @deftypevr {@code{openvpn-server-configuration} parameter} number port
21392 Specifies the port number on which the server listens.
21394 Defaults to @samp{1194}.
21398 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
21399 An ip and mask specifying the subnet inside the virtual network.
21401 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
21405 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
21406 A CIDR notation specifying the IPv6 subnet inside the virtual network.
21408 Defaults to @samp{#f}.
21412 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
21413 The Diffie-Hellman parameters file.
21415 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
21419 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
21420 The file that records client IPs.
21422 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
21426 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
21427 When true, the server will act as a gateway for its clients.
21429 Defaults to @samp{#f}.
21433 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
21434 When true, clients are allowed to talk to each other inside the VPN.
21436 Defaults to @samp{#f}.
21440 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
21441 Causes ping-like messages to be sent back and forth over the link so
21442 that each side knows when the other side has gone down. @code{keepalive}
21443 requires a pair. The first element is the period of the ping sending,
21444 and the second element is the timeout before considering the other side
21449 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
21450 The maximum number of clients.
21452 Defaults to @samp{100}.
21456 @deftypevr {@code{openvpn-server-configuration} parameter} string status
21457 The status file. This file shows a small report on current connection.
21458 It is truncated and rewritten every minute.
21460 Defaults to @samp{"/var/run/openvpn/status"}.
21464 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
21465 The list of configuration for some clients.
21467 Defaults to @samp{()}.
21469 Available @code{openvpn-ccd-configuration} fields are:
21471 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
21474 Defaults to @samp{"client"}.
21478 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
21481 Defaults to @samp{#f}.
21485 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
21488 Defaults to @samp{#f}.
21495 @c %end of automatic openvpn-server documentation
21498 @node Network File System
21499 @subsection Network File System
21502 The @code{(gnu services nfs)} module provides the following services,
21503 which are most commonly used in relation to mounting or exporting
21504 directory trees as @dfn{network file systems} (NFS).
21506 @subsubheading RPC Bind Service
21509 The RPC Bind service provides a facility to map program numbers into
21510 universal addresses.
21511 Many NFS related services use this facility. Hence it is automatically
21512 started when a dependent service starts.
21514 @defvr {Scheme Variable} rpcbind-service-type
21515 A service type for the RPC portmapper daemon.
21519 @deftp {Data Type} rpcbind-configuration
21520 Data type representing the configuration of the RPC Bind Service.
21521 This type has the following parameters:
21523 @item @code{rpcbind} (default: @code{rpcbind})
21524 The rpcbind package to use.
21526 @item @code{warm-start?} (default: @code{#t})
21527 If this parameter is @code{#t}, then the daemon will read a
21528 state file on startup thus reloading state information saved by a previous
21534 @subsubheading Pipefs Pseudo File System
21538 The pipefs file system is used to transfer NFS related data
21539 between the kernel and user space programs.
21541 @defvr {Scheme Variable} pipefs-service-type
21542 A service type for the pipefs pseudo file system.
21545 @deftp {Data Type} pipefs-configuration
21546 Data type representing the configuration of the pipefs pseudo file system service.
21547 This type has the following parameters:
21549 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21550 The directory to which the file system is to be attached.
21555 @subsubheading GSS Daemon Service
21558 @cindex global security system
21560 The @dfn{global security system} (GSS) daemon provides strong security for RPC
21562 Before exchanging RPC requests an RPC client must establish a security
21563 context. Typically this is done using the Kerberos command @command{kinit}
21564 or automatically at login time using PAM services (@pxref{Kerberos Services}).
21566 @defvr {Scheme Variable} gss-service-type
21567 A service type for the Global Security System (GSS) daemon.
21570 @deftp {Data Type} gss-configuration
21571 Data type representing the configuration of the GSS daemon service.
21572 This type has the following parameters:
21574 @item @code{nfs-utils} (default: @code{nfs-utils})
21575 The package in which the @command{rpc.gssd} command is to be found.
21577 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21578 The directory where the pipefs file system is mounted.
21584 @subsubheading IDMAP Daemon Service
21586 @cindex name mapper
21588 The idmap daemon service provides mapping between user IDs and user names.
21589 Typically it is required in order to access file systems mounted via NFSv4.
21591 @defvr {Scheme Variable} idmap-service-type
21592 A service type for the Identity Mapper (IDMAP) daemon.
21595 @deftp {Data Type} idmap-configuration
21596 Data type representing the configuration of the IDMAP daemon service.
21597 This type has the following parameters:
21599 @item @code{nfs-utils} (default: @code{nfs-utils})
21600 The package in which the @command{rpc.idmapd} command is to be found.
21602 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21603 The directory where the pipefs file system is mounted.
21605 @item @code{domain} (default: @code{#f})
21606 The local NFSv4 domain name.
21607 This must be a string or @code{#f}.
21608 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
21613 @node Continuous Integration
21614 @subsection Continuous Integration
21616 @cindex continuous integration
21617 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
21618 continuous integration tool for Guix. It can be used both for development and
21619 for providing substitutes to others (@pxref{Substitutes}).
21621 The @code{(gnu services cuirass)} module provides the following service.
21623 @defvr {Scheme Procedure} cuirass-service-type
21624 The type of the Cuirass service. Its value must be a
21625 @code{cuirass-configuration} object, as described below.
21628 To add build jobs, you have to set the @code{specifications} field of the
21629 configuration. Here is an example of a service that polls the Guix repository
21630 and builds the packages from a manifest. Some of the packages are defined in
21631 the @code{"custom-packages"} input, which is the equivalent of
21632 @code{GUIX_PACKAGE_PATH}.
21635 (define %cuirass-specs
21637 '((#:name . "my-manifest")
21638 (#:load-path-inputs . ("guix"))
21639 (#:package-path-inputs . ("custom-packages"))
21640 (#:proc-input . "guix")
21641 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
21642 (#:proc . cuirass-jobs)
21643 (#:proc-args . ((subset . "manifests")
21644 (systems . ("x86_64-linux"))
21645 (manifests . (("config" . "guix/manifest.scm")))))
21646 (#:inputs . (((#:name . "guix")
21647 (#:url . "git://git.savannah.gnu.org/guix.git")
21648 (#:load-path . ".")
21649 (#:branch . "master")
21650 (#:no-compile? . #t))
21651 ((#:name . "config")
21652 (#:url . "https://git.example.org/config.git")
21653 (#:load-path . ".")
21654 (#:branch . "master")
21655 (#:no-compile? . #t))
21656 ((#:name . "custom-packages")
21657 (#:url . "https://git.example.org/custom-packages.git")
21658 (#:load-path . ".")
21659 (#:branch . "master")
21660 (#:no-compile? . #t)))))))
21662 (service cuirass-service-type
21663 (cuirass-configuration
21664 (specifications %cuirass-specs)))
21667 While information related to build jobs is located directly in the
21668 specifications, global settings for the @command{cuirass} process are
21669 accessible in other @code{cuirass-configuration} fields.
21671 @deftp {Data Type} cuirass-configuration
21672 Data type representing the configuration of Cuirass.
21675 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
21676 Location of the log file.
21678 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
21679 Location of the log file used by the web interface.
21681 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
21682 Location of the repository cache.
21684 @item @code{user} (default: @code{"cuirass"})
21685 Owner of the @code{cuirass} process.
21687 @item @code{group} (default: @code{"cuirass"})
21688 Owner's group of the @code{cuirass} process.
21690 @item @code{interval} (default: @code{60})
21691 Number of seconds between the poll of the repositories followed by the
21694 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
21695 Location of sqlite database which contains the build results and previously
21696 added specifications.
21698 @item @code{ttl} (default: @code{(* 30 24 3600)})
21699 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
21700 are registered for build results. This means that build results are protected
21701 from garbage collection for at least @var{ttl} seconds.
21703 @item @code{port} (default: @code{8081})
21704 Port number used by the HTTP server.
21706 @item @code{host} (default: @code{"localhost"})
21707 Listen on the network interface for @var{host}. The default is to
21708 accept connections from localhost.
21710 @item @code{specifications} (default: @code{#~'()})
21711 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
21712 where a specification is an association list
21713 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
21714 keys are keywords (@code{#:keyword-example}) as shown in the example
21717 @item @code{use-substitutes?} (default: @code{#f})
21718 This allows using substitutes to avoid building every dependencies of a job
21721 @item @code{one-shot?} (default: @code{#f})
21722 Only evaluate specifications and build derivations once.
21724 @item @code{fallback?} (default: @code{#f})
21725 When substituting a pre-built binary fails, fall back to building
21728 @item @code{cuirass} (default: @code{cuirass})
21729 The Cuirass package to use.
21733 @node Power Management Services
21734 @subsection Power Management Services
21737 @cindex power management with TLP
21738 @subsubheading TLP daemon
21740 The @code{(gnu services pm)} module provides a Guix service definition
21741 for the Linux power management tool TLP.
21743 TLP enables various powersaving modes in userspace and kernel.
21744 Contrary to @code{upower-service}, it is not a passive,
21745 monitoring tool, as it will apply custom settings each time a new power
21746 source is detected. More information can be found at
21747 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
21749 @deffn {Scheme Variable} tlp-service-type
21750 The service type for the TLP tool. Its value should be a valid
21751 TLP configuration (see below). To use the default settings, simply
21754 (service tlp-service-type)
21758 By default TLP does not need much configuration but most TLP parameters
21759 can be tweaked using @code{tlp-configuration}.
21761 Each parameter definition is preceded by its type; for example,
21762 @samp{boolean foo} indicates that the @code{foo} parameter
21763 should be specified as a boolean. Types starting with
21764 @code{maybe-} denote parameters that won't show up in TLP config file
21765 when their value is @code{'disabled}.
21767 @c The following documentation was initially generated by
21768 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
21769 @c documentation is better, so we shouldn't hesitate to edit below as
21770 @c needed. However if the change you want to make to this documentation
21771 @c can be done in an automated way, it's probably easier to change
21772 @c (generate-documentation) than to make it below and have to deal with
21773 @c the churn as TLP updates.
21775 Available @code{tlp-configuration} fields are:
21777 @deftypevr {@code{tlp-configuration} parameter} package tlp
21782 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
21783 Set to true if you wish to enable TLP.
21785 Defaults to @samp{#t}.
21789 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
21790 Default mode when no power supply can be detected. Alternatives are AC
21793 Defaults to @samp{"AC"}.
21797 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
21798 Number of seconds Linux kernel has to wait after the disk goes idle,
21799 before syncing on AC.
21801 Defaults to @samp{0}.
21805 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
21806 Same as @code{disk-idle-ac} but on BAT mode.
21808 Defaults to @samp{2}.
21812 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
21813 Dirty pages flushing periodicity, expressed in seconds.
21815 Defaults to @samp{15}.
21819 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
21820 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
21822 Defaults to @samp{60}.
21826 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
21827 CPU frequency scaling governor on AC mode. With intel_pstate driver,
21828 alternatives are powersave and performance. With acpi-cpufreq driver,
21829 alternatives are ondemand, powersave, performance and conservative.
21831 Defaults to @samp{disabled}.
21835 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
21836 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
21838 Defaults to @samp{disabled}.
21842 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
21843 Set the min available frequency for the scaling governor on AC.
21845 Defaults to @samp{disabled}.
21849 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
21850 Set the max available frequency for the scaling governor on AC.
21852 Defaults to @samp{disabled}.
21856 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
21857 Set the min available frequency for the scaling governor on BAT.
21859 Defaults to @samp{disabled}.
21863 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
21864 Set the max available frequency for the scaling governor on BAT.
21866 Defaults to @samp{disabled}.
21870 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
21871 Limit the min P-state to control the power dissipation of the CPU, in AC
21872 mode. Values are stated as a percentage of the available performance.
21874 Defaults to @samp{disabled}.
21878 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
21879 Limit the max P-state to control the power dissipation of the CPU, in AC
21880 mode. Values are stated as a percentage of the available performance.
21882 Defaults to @samp{disabled}.
21886 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
21887 Same as @code{cpu-min-perf-on-ac} on BAT mode.
21889 Defaults to @samp{disabled}.
21893 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
21894 Same as @code{cpu-max-perf-on-ac} on BAT mode.
21896 Defaults to @samp{disabled}.
21900 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
21901 Enable CPU turbo boost feature on AC mode.
21903 Defaults to @samp{disabled}.
21907 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
21908 Same as @code{cpu-boost-on-ac?} on BAT mode.
21910 Defaults to @samp{disabled}.
21914 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
21915 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
21916 used under light load conditions.
21918 Defaults to @samp{#f}.
21922 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
21923 Same as @code{sched-powersave-on-ac?} but on BAT mode.
21925 Defaults to @samp{#t}.
21929 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
21930 Enable Linux kernel NMI watchdog.
21932 Defaults to @samp{#f}.
21936 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
21937 For Linux kernels with PHC patch applied, change CPU voltages. An
21938 example value would be @samp{"F:V F:V F:V F:V"}.
21940 Defaults to @samp{disabled}.
21944 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
21945 Set CPU performance versus energy saving policy on AC. Alternatives are
21946 performance, normal, powersave.
21948 Defaults to @samp{"performance"}.
21952 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
21953 Same as @code{energy-perf-policy-ac} but on BAT mode.
21955 Defaults to @samp{"powersave"}.
21959 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
21964 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
21965 Hard disk advanced power management level.
21969 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
21970 Same as @code{disk-apm-bat} but on BAT mode.
21974 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
21975 Hard disk spin down timeout. One value has to be specified for each
21976 declared hard disk.
21978 Defaults to @samp{disabled}.
21982 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
21983 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
21985 Defaults to @samp{disabled}.
21989 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
21990 Select IO scheduler for disk devices. One value has to be specified for
21991 each declared hard disk. Example alternatives are cfq, deadline and
21994 Defaults to @samp{disabled}.
21998 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
21999 SATA aggressive link power management (ALPM) level. Alternatives are
22000 min_power, medium_power, max_performance.
22002 Defaults to @samp{"max_performance"}.
22006 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
22007 Same as @code{sata-linkpwr-ac} but on BAT mode.
22009 Defaults to @samp{"min_power"}.
22013 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
22014 Exclude specified SATA host devices for link power management.
22016 Defaults to @samp{disabled}.
22020 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
22021 Enable Runtime Power Management for AHCI controller and disks on AC
22024 Defaults to @samp{disabled}.
22028 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
22029 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
22031 Defaults to @samp{disabled}.
22035 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
22036 Seconds of inactivity before disk is suspended.
22038 Defaults to @samp{15}.
22042 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
22043 PCI Express Active State Power Management level. Alternatives are
22044 default, performance, powersave.
22046 Defaults to @samp{"performance"}.
22050 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
22051 Same as @code{pcie-aspm-ac} but on BAT mode.
22053 Defaults to @samp{"powersave"}.
22057 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
22058 Radeon graphics clock speed level. Alternatives are low, mid, high,
22061 Defaults to @samp{"high"}.
22065 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
22066 Same as @code{radeon-power-ac} but on BAT mode.
22068 Defaults to @samp{"low"}.
22072 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
22073 Radeon dynamic power management method (DPM). Alternatives are battery,
22076 Defaults to @samp{"performance"}.
22080 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
22081 Same as @code{radeon-dpm-state-ac} but on BAT mode.
22083 Defaults to @samp{"battery"}.
22087 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
22088 Radeon DPM performance level. Alternatives are auto, low, high.
22090 Defaults to @samp{"auto"}.
22094 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
22095 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
22097 Defaults to @samp{"auto"}.
22101 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
22102 Wifi power saving mode.
22104 Defaults to @samp{#f}.
22108 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
22109 Same as @code{wifi-power-ac?} but on BAT mode.
22111 Defaults to @samp{#t}.
22115 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
22116 Disable wake on LAN.
22118 Defaults to @samp{#t}.
22122 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
22123 Timeout duration in seconds before activating audio power saving on
22124 Intel HDA and AC97 devices. A value of 0 disables power saving.
22126 Defaults to @samp{0}.
22130 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
22131 Same as @code{sound-powersave-ac} but on BAT mode.
22133 Defaults to @samp{1}.
22137 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
22138 Disable controller in powersaving mode on Intel HDA devices.
22140 Defaults to @samp{#t}.
22144 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
22145 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
22146 powered on again by releasing (and reinserting) the eject lever or by
22147 pressing the disc eject button on newer models.
22149 Defaults to @samp{#f}.
22153 @deftypevr {@code{tlp-configuration} parameter} string bay-device
22154 Name of the optical drive device to power off.
22156 Defaults to @samp{"sr0"}.
22160 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
22161 Runtime Power Management for PCI(e) bus devices. Alternatives are on
22164 Defaults to @samp{"on"}.
22168 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
22169 Same as @code{runtime-pm-ac} but on BAT mode.
22171 Defaults to @samp{"auto"}.
22175 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
22176 Runtime Power Management for all PCI(e) bus devices, except blacklisted
22179 Defaults to @samp{#t}.
22183 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
22184 Exclude specified PCI(e) device addresses from Runtime Power Management.
22186 Defaults to @samp{disabled}.
22190 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
22191 Exclude PCI(e) devices assigned to the specified drivers from Runtime
22196 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
22197 Enable USB autosuspend feature.
22199 Defaults to @samp{#t}.
22203 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
22204 Exclude specified devices from USB autosuspend.
22206 Defaults to @samp{disabled}.
22210 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
22211 Exclude WWAN devices from USB autosuspend.
22213 Defaults to @samp{#t}.
22217 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
22218 Include specified devices into USB autosuspend, even if they are already
22219 excluded by the driver or via @code{usb-blacklist-wwan?}.
22221 Defaults to @samp{disabled}.
22225 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
22226 Enable USB autosuspend before shutdown.
22228 Defaults to @samp{disabled}.
22232 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
22233 Restore radio device state (bluetooth, wifi, wwan) from previous
22234 shutdown on system startup.
22236 Defaults to @samp{#f}.
22241 @cindex CPU frequency scaling with thermald
22242 @subsubheading Thermald daemon
22244 The @code{(gnu services pm)} module provides an interface to
22245 thermald, a CPU frequency scaling service which helps prevent overheating.
22247 @defvr {Scheme Variable} thermald-service-type
22248 This is the service type for
22249 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
22250 Thermal Daemon, which is responsible for controlling the thermal state
22251 of processors and preventing overheating.
22254 @deftp {Data Type} thermald-configuration
22255 Data type representing the configuration of @code{thermald-service-type}.
22258 @item @code{ignore-cpuid-check?} (default: @code{#f})
22259 Ignore cpuid check for supported CPU models.
22261 @item @code{thermald} (default: @var{thermald})
22262 Package object of thermald.
22267 @node Audio Services
22268 @subsection Audio Services
22270 The @code{(gnu services audio)} module provides a service to start MPD
22271 (the Music Player Daemon).
22274 @subsubheading Music Player Daemon
22276 The Music Player Daemon (MPD) is a service that can play music while
22277 being controlled from the local machine or over the network by a variety
22280 The following example shows how one might run @code{mpd} as user
22281 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
22284 (service mpd-service-type
22290 @defvr {Scheme Variable} mpd-service-type
22291 The service type for @command{mpd}
22294 @deftp {Data Type} mpd-configuration
22295 Data type representing the configuration of @command{mpd}.
22298 @item @code{user} (default: @code{"mpd"})
22299 The user to run mpd as.
22301 @item @code{music-dir} (default: @code{"~/Music"})
22302 The directory to scan for music files.
22304 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
22305 The directory to store playlists.
22307 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
22308 The location of the music database.
22310 @item @code{state-file} (default: @code{"~/.mpd/state"})
22311 The location of the file that stores current MPD's state.
22313 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
22314 The location of the sticker database.
22316 @item @code{port} (default: @code{"6600"})
22317 The port to run mpd on.
22319 @item @code{address} (default: @code{"any"})
22320 The address that mpd will bind to. To use a Unix domain socket,
22321 an absolute path can be specified here.
22326 @node Virtualization Services
22327 @subsection Virtualization services
22329 The @code{(gnu services virtualization)} module provides services for
22330 the libvirt and virtlog daemons, as well as other virtualization-related
22333 @subsubheading Libvirt daemon
22334 @code{libvirtd} is the server side daemon component of the libvirt
22335 virtualization management system. This daemon runs on host servers
22336 and performs required management tasks for virtualized guests.
22338 @deffn {Scheme Variable} libvirt-service-type
22339 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
22340 Its value must be a @code{libvirt-configuration}.
22343 (service libvirt-service-type
22344 (libvirt-configuration
22345 (unix-sock-group "libvirt")
22346 (tls-port "16555")))
22350 @c Auto-generated with (generate-libvirt-documentation)
22351 Available @code{libvirt-configuration} fields are:
22353 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
22358 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
22359 Flag listening for secure TLS connections on the public TCP/IP port.
22360 must set @code{listen} for this to have any effect.
22362 It is necessary to setup a CA and issue server certificates before using
22365 Defaults to @samp{#t}.
22369 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
22370 Listen for unencrypted TCP connections on the public TCP/IP port. must
22371 set @code{listen} for this to have any effect.
22373 Using the TCP socket requires SASL authentication by default. Only SASL
22374 mechanisms which support data encryption are allowed. This is
22375 DIGEST_MD5 and GSSAPI (Kerberos5)
22377 Defaults to @samp{#f}.
22381 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
22382 Port for accepting secure TLS connections This can be a port number, or
22385 Defaults to @samp{"16514"}.
22389 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
22390 Port for accepting insecure TCP connections This can be a port number,
22393 Defaults to @samp{"16509"}.
22397 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
22398 IP address or hostname used for client connections.
22400 Defaults to @samp{"0.0.0.0"}.
22404 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
22405 Flag toggling mDNS advertisement of the libvirt service.
22407 Alternatively can disable for all services on a host by stopping the
22410 Defaults to @samp{#f}.
22414 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
22415 Default mDNS advertisement name. This must be unique on the immediate
22418 Defaults to @samp{"Virtualization Host <hostname>"}.
22422 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
22423 UNIX domain socket group ownership. This can be used to allow a
22424 'trusted' set of users access to management capabilities without
22427 Defaults to @samp{"root"}.
22431 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
22432 UNIX socket permissions for the R/O socket. This is used for monitoring
22435 Defaults to @samp{"0777"}.
22439 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
22440 UNIX socket permissions for the R/W socket. Default allows only root.
22441 If PolicyKit is enabled on the socket, the default will change to allow
22442 everyone (eg, 0777)
22444 Defaults to @samp{"0770"}.
22448 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
22449 UNIX socket permissions for the admin socket. Default allows only owner
22450 (root), do not change it unless you are sure to whom you are exposing
22453 Defaults to @samp{"0777"}.
22457 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
22458 The directory in which sockets will be found/created.
22460 Defaults to @samp{"/var/run/libvirt"}.
22464 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
22465 Authentication scheme for UNIX read-only sockets. By default socket
22466 permissions allow anyone to connect
22468 Defaults to @samp{"polkit"}.
22472 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
22473 Authentication scheme for UNIX read-write sockets. By default socket
22474 permissions only allow root. If PolicyKit support was compiled into
22475 libvirt, the default will be to use 'polkit' auth.
22477 Defaults to @samp{"polkit"}.
22481 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
22482 Authentication scheme for TCP sockets. If you don't enable SASL, then
22483 all TCP traffic is cleartext. Don't do this outside of a dev/test
22486 Defaults to @samp{"sasl"}.
22490 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
22491 Authentication scheme for TLS sockets. TLS sockets already have
22492 encryption provided by the TLS layer, and limited authentication is done
22495 It is possible to make use of any SASL authentication mechanism as well,
22496 by using 'sasl' for this option
22498 Defaults to @samp{"none"}.
22502 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
22503 API access control scheme.
22505 By default an authenticated user is allowed access to all APIs. Access
22506 drivers can place restrictions on this.
22508 Defaults to @samp{()}.
22512 @deftypevr {@code{libvirt-configuration} parameter} string key-file
22513 Server key file path. If set to an empty string, then no private key is
22516 Defaults to @samp{""}.
22520 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
22521 Server key file path. If set to an empty string, then no certificate is
22524 Defaults to @samp{""}.
22528 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
22529 Server key file path. If set to an empty string, then no CA certificate
22532 Defaults to @samp{""}.
22536 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
22537 Certificate revocation list path. If set to an empty string, then no
22540 Defaults to @samp{""}.
22544 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
22545 Disable verification of our own server certificates.
22547 When libvirtd starts it performs some sanity checks against its own
22550 Defaults to @samp{#f}.
22554 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
22555 Disable verification of client certificates.
22557 Client certificate verification is the primary authentication mechanism.
22558 Any client which does not present a certificate signed by the CA will be
22561 Defaults to @samp{#f}.
22565 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
22566 Whitelist of allowed x509 Distinguished Name.
22568 Defaults to @samp{()}.
22572 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
22573 Whitelist of allowed SASL usernames. The format for username depends on
22574 the SASL authentication mechanism.
22576 Defaults to @samp{()}.
22580 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
22581 Override the compile time default TLS priority string. The default is
22582 usually "NORMAL" unless overridden at build time. Only set this is it
22583 is desired for libvirt to deviate from the global default settings.
22585 Defaults to @samp{"NORMAL"}.
22589 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
22590 Maximum number of concurrent client connections to allow over all
22593 Defaults to @samp{5000}.
22597 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
22598 Maximum length of queue of connections waiting to be accepted by the
22599 daemon. Note, that some protocols supporting retransmission may obey
22600 this so that a later reattempt at connection succeeds.
22602 Defaults to @samp{1000}.
22606 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
22607 Maximum length of queue of accepted but not yet authenticated clients.
22608 Set this to zero to turn this feature off
22610 Defaults to @samp{20}.
22614 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
22615 Number of workers to start up initially.
22617 Defaults to @samp{5}.
22621 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
22622 Maximum number of worker threads.
22624 If the number of active clients exceeds @code{min-workers}, then more
22625 threads are spawned, up to max_workers limit. Typically you'd want
22626 max_workers to equal maximum number of clients allowed.
22628 Defaults to @samp{20}.
22632 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
22633 Number of priority workers. If all workers from above pool are stuck,
22634 some calls marked as high priority (notably domainDestroy) can be
22635 executed in this pool.
22637 Defaults to @samp{5}.
22641 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
22642 Total global limit on concurrent RPC calls.
22644 Defaults to @samp{20}.
22648 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
22649 Limit on concurrent requests from a single client connection. To avoid
22650 one client monopolizing the server this should be a small fraction of
22651 the global max_requests and max_workers parameter.
22653 Defaults to @samp{5}.
22657 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
22658 Same as @code{min-workers} but for the admin interface.
22660 Defaults to @samp{1}.
22664 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
22665 Same as @code{max-workers} but for the admin interface.
22667 Defaults to @samp{5}.
22671 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
22672 Same as @code{max-clients} but for the admin interface.
22674 Defaults to @samp{5}.
22678 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
22679 Same as @code{max-queued-clients} but for the admin interface.
22681 Defaults to @samp{5}.
22685 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
22686 Same as @code{max-client-requests} but for the admin interface.
22688 Defaults to @samp{5}.
22692 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
22693 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22695 Defaults to @samp{3}.
22699 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
22702 A filter allows to select a different logging level for a given category
22703 of logs The format for a filter is one of:
22714 where @code{name} is a string which is matched against the category
22715 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22716 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22717 be a substring of the full category name, in order to match multiple
22718 similar categories), the optional "+" prefix tells libvirt to log stack
22719 trace for each message matching name, and @code{x} is the minimal level
22720 where matching messages should be logged:
22737 Multiple filters can be defined in a single filters statement, they just
22738 need to be separated by spaces.
22740 Defaults to @samp{"3:remote 4:event"}.
22744 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
22747 An output is one of the places to save logging information. The format
22748 for an output can be:
22752 output goes to stderr
22754 @item x:syslog:name
22755 use syslog for the output and use the given name as the ident
22757 @item x:file:file_path
22758 output to a file, with the given filepath
22761 output to journald logging system
22765 In all case the x prefix is the minimal level, acting as a filter
22782 Multiple outputs can be defined, they just need to be separated by
22785 Defaults to @samp{"3:stderr"}.
22789 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
22790 Allows usage of the auditing subsystem to be altered
22794 0: disable all auditing
22797 1: enable auditing, only if enabled on host
22800 2: enable auditing, and exit if disabled on host.
22804 Defaults to @samp{1}.
22808 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
22809 Send audit messages via libvirt logging infrastructure.
22811 Defaults to @samp{#f}.
22815 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
22816 Host UUID. UUID must not have all digits be the same.
22818 Defaults to @samp{""}.
22822 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
22823 Source to read host UUID.
22827 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
22830 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
22834 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
22837 Defaults to @samp{"smbios"}.
22841 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
22842 A keepalive message is sent to a client after @code{keepalive_interval}
22843 seconds of inactivity to check if the client is still responding. If
22844 set to -1, libvirtd will never send keepalive requests; however clients
22845 can still send them and the daemon will send responses.
22847 Defaults to @samp{5}.
22851 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
22852 Maximum number of keepalive messages that are allowed to be sent to the
22853 client without getting any response before the connection is considered
22856 In other words, the connection is automatically closed approximately
22857 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
22858 the last message received from the client. When @code{keepalive-count}
22859 is set to 0, connections will be automatically closed after
22860 @code{keepalive-interval} seconds of inactivity without sending any
22861 keepalive messages.
22863 Defaults to @samp{5}.
22867 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
22868 Same as above but for admin interface.
22870 Defaults to @samp{5}.
22874 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
22875 Same as above but for admin interface.
22877 Defaults to @samp{5}.
22881 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
22882 Timeout for Open vSwitch calls.
22884 The @code{ovs-vsctl} utility is used for the configuration and its
22885 timeout option is set by default to 5 seconds to avoid potential
22886 infinite waits blocking libvirt.
22888 Defaults to @samp{5}.
22892 @c %end of autogenerated docs
22894 @subsubheading Virtlog daemon
22895 The virtlogd service is a server side daemon component of libvirt that is
22896 used to manage logs from virtual machine consoles.
22898 This daemon is not used directly by libvirt client applications, rather it
22899 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
22900 standalone daemon, the main @code{libvirtd} daemon can be restarted without
22901 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
22902 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
22904 @deffn {Scheme Variable} virtlog-service-type
22905 This is the type of the virtlog daemon.
22906 Its value must be a @code{virtlog-configuration}.
22909 (service virtlog-service-type
22910 (virtlog-configuration
22911 (max-clients 1000)))
22915 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
22916 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22918 Defaults to @samp{3}.
22922 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
22925 A filter allows to select a different logging level for a given category
22926 of logs The format for a filter is one of:
22937 where @code{name} is a string which is matched against the category
22938 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22939 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22940 be a substring of the full category name, in order to match multiple
22941 similar categories), the optional "+" prefix tells libvirt to log stack
22942 trace for each message matching name, and @code{x} is the minimal level
22943 where matching messages should be logged:
22960 Multiple filters can be defined in a single filters statement, they just
22961 need to be separated by spaces.
22963 Defaults to @samp{"3:remote 4:event"}.
22967 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
22970 An output is one of the places to save logging information The format
22971 for an output can be:
22975 output goes to stderr
22977 @item x:syslog:name
22978 use syslog for the output and use the given name as the ident
22980 @item x:file:file_path
22981 output to a file, with the given filepath
22984 output to journald logging system
22988 In all case the x prefix is the minimal level, acting as a filter
23005 Multiple outputs can be defined, they just need to be separated by
23008 Defaults to @samp{"3:stderr"}.
23012 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
23013 Maximum number of concurrent client connections to allow over all
23016 Defaults to @samp{1024}.
23020 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
23021 Maximum file size before rolling over.
23023 Defaults to @samp{2MB}
23027 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
23028 Maximum number of backup files to keep.
23030 Defaults to @samp{3}
23034 @subsubheading Transparent Emulation with QEMU
23037 @cindex @code{binfmt_misc}
23038 @code{qemu-binfmt-service-type} provides support for transparent
23039 emulation of program binaries built for different architectures---e.g.,
23040 it allows you to transparently execute an ARMv7 program on an x86_64
23041 machine. It achieves this by combining the @uref{https://www.qemu.org,
23042 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
23044 @defvr {Scheme Variable} qemu-binfmt-service-type
23045 This is the type of the QEMU/binfmt service for transparent emulation.
23046 Its value must be a @code{qemu-binfmt-configuration} object, which
23047 specifies the QEMU package to use as well as the architecture we want to
23051 (service qemu-binfmt-service-type
23052 (qemu-binfmt-configuration
23053 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
23056 In this example, we enable transparent emulation for the ARM and aarch64
23057 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
23058 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
23059 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
23062 @deftp {Data Type} qemu-binfmt-configuration
23063 This is the configuration for the @code{qemu-binfmt} service.
23066 @item @code{platforms} (default: @code{'()})
23067 The list of emulated QEMU platforms. Each item must be a @dfn{platform
23068 object} as returned by @code{lookup-qemu-platforms} (see below).
23070 @item @code{guix-support?} (default: @code{#f})
23071 When it is true, QEMU and all its dependencies are added to the build
23072 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
23073 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
23074 handlers to be used within the build environment, which in turn means
23075 that you can transparently build programs for another architecture.
23077 For example, let's suppose you're on an x86_64 machine and you have this
23081 (service qemu-binfmt-service-type
23082 (qemu-binfmt-configuration
23083 (platforms (lookup-qemu-platforms "arm"))
23084 (guix-support? #t)))
23090 guix build -s armhf-linux inkscape
23094 and it will build Inkscape for ARMv7 @emph{as if it were a native
23095 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
23096 if you'd like to test a package build for an architecture you don't have
23099 @item @code{qemu} (default: @code{qemu})
23100 The QEMU package to use.
23104 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
23105 Return the list of QEMU platform objects corresponding to
23106 @var{platforms}@dots{}. @var{platforms} must be a list of strings
23107 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
23108 @code{"mips64el"}, and so on.
23111 @deffn {Scheme Procedure} qemu-platform? @var{obj}
23112 Return true if @var{obj} is a platform object.
23115 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
23116 Return the name of @var{platform}---a string such as @code{"arm"}.
23119 @node Version Control Services
23120 @subsection Version Control Services
23122 The @code{(gnu services version-control)} module provides a service to
23123 allow remote access to local Git repositories. There are three options:
23124 the @code{git-daemon-service}, which provides access to repositories via
23125 the @code{git://} unsecured TCP-based protocol, extending the
23126 @code{nginx} web server to proxy some requests to
23127 @code{git-http-backend}, or providing a web interface with
23128 @code{cgit-service-type}.
23130 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
23132 Return a service that runs @command{git daemon}, a simple TCP server to
23133 expose repositories over the Git protocol for anonymous access.
23135 The optional @var{config} argument should be a
23136 @code{<git-daemon-configuration>} object, by default it allows read-only
23137 access to exported@footnote{By creating the magic file
23138 "git-daemon-export-ok" in the repository directory.} repositories under
23143 @deftp {Data Type} git-daemon-configuration
23144 Data type representing the configuration for @code{git-daemon-service}.
23147 @item @code{package} (default: @var{git})
23148 Package object of the Git distributed version control system.
23150 @item @code{export-all?} (default: @var{#f})
23151 Whether to allow access for all Git repositories, even if they do not
23152 have the @file{git-daemon-export-ok} file.
23154 @item @code{base-path} (default: @file{/srv/git})
23155 Whether to remap all the path requests as relative to the given path.
23156 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
23157 then if you later try to pull @code{git://example.com/hello.git}, git
23158 daemon will interpret the path as @code{/srv/git/hello.git}.
23160 @item @code{user-path} (default: @var{#f})
23161 Whether to allow @code{~user} notation to be used in requests. When
23162 specified with empty string, requests to @code{git://host/~alice/foo} is
23163 taken as a request to access @code{foo} repository in the home directory
23164 of user @code{alice}. If @var{(user-path "path")} is specified, the
23165 same request is taken as a request to access @code{path/foo} repository
23166 in the home directory of user @code{alice}.
23168 @item @code{listen} (default: @var{'()})
23169 Whether to listen on specific IP addresses or hostnames, defaults to
23172 @item @code{port} (default: @var{#f})
23173 Whether to listen on an alternative port, which defaults to 9418.
23175 @item @code{whitelist} (default: @var{'()})
23176 If not empty, only allow access to this list of directories.
23178 @item @code{extra-options} (default: @var{'()})
23179 Extra options will be passed to @code{git daemon}, please run
23180 @command{man git-daemon} for more information.
23185 The @code{git://} protocol lacks authentication. When you pull from a
23186 repository fetched via @code{git://}, you don't know whether the data you
23187 receive was modified or is even coming from the specified host, and your
23188 connection is subject to eavesdropping. It's better to use an authenticated
23189 and encrypted transport, such as @code{https}. Although Git allows you
23190 to serve repositories using unsophisticated file-based web servers,
23191 there is a faster protocol implemented by the @code{git-http-backend}
23192 program. This program is the back-end of a proper Git web service. It
23193 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
23194 on running the necessary @code{fcgiwrap} daemon.
23196 Guix has a separate configuration data type for serving Git repositories
23199 @deftp {Data Type} git-http-configuration
23200 Data type representing the configuration for @code{git-http-service}.
23203 @item @code{package} (default: @var{git})
23204 Package object of the Git distributed version control system.
23206 @item @code{git-root} (default: @file{/srv/git})
23207 Directory containing the Git repositories to expose to the world.
23209 @item @code{export-all?} (default: @var{#f})
23210 Whether to expose access for all Git repositories in @var{git-root},
23211 even if they do not have the @file{git-daemon-export-ok} file.
23213 @item @code{uri-path} (default: @file{/git/})
23214 Path prefix for Git access. With the default @code{/git/} prefix, this
23215 will map @code{http://@var{server}/git/@var{repo}.git} to
23216 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
23217 with this prefix are not passed on to this Git instance.
23219 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
23220 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
23225 There is no @code{git-http-service-type}, currently; instead you can
23226 create an @code{nginx-location-configuration} from a
23227 @code{git-http-configuration} and then add that location to a web
23230 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
23231 [config=(git-http-configuration)]
23232 Compute an @code{nginx-location-configuration} that corresponds to the
23233 given Git http configuration. An example nginx service definition to
23234 serve the default @file{/srv/git} over HTTPS might be:
23237 (service nginx-service-type
23238 (nginx-configuration
23241 (nginx-server-configuration
23242 (listen '("443 ssl"))
23243 (server-name "git.my-host.org")
23245 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
23246 (ssl-certificate-key
23247 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
23250 (git-http-nginx-location-configuration
23251 (git-http-configuration (uri-path "/"))))))))))
23254 This example assumes that you are using Let's Encrypt to get your TLS
23255 certificate. @xref{Certificate Services}. The default @code{certbot}
23256 service will redirect all HTTP traffic on @code{git.my-host.org} to
23257 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
23258 system services. @xref{Web Services}.
23261 @subsubheading Cgit Service
23263 @cindex Cgit service
23264 @cindex Git, web interface
23265 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
23266 repositories written in C.
23268 The following example will configure the service with default values.
23269 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
23272 (service cgit-service-type)
23275 The @code{file-object} type designates either a file-like object
23276 (@pxref{G-Expressions, file-like objects}) or a string.
23278 @c %start of fragment
23280 Available @code{cgit-configuration} fields are:
23282 @deftypevr {@code{cgit-configuration} parameter} package package
23287 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
23288 NGINX configuration.
23292 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
23293 Specifies a command which will be invoked to format the content of about
23294 pages (both top-level and for each repository).
23296 Defaults to @samp{""}.
23300 @deftypevr {@code{cgit-configuration} parameter} string agefile
23301 Specifies a path, relative to each repository path, which can be used to
23302 specify the date and time of the youngest commit in the repository.
23304 Defaults to @samp{""}.
23308 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
23309 Specifies a command that will be invoked for authenticating repository
23312 Defaults to @samp{""}.
23316 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
23317 Flag which, when set to @samp{age}, enables date ordering in the branch
23318 ref list, and when set @samp{name} enables ordering by branch name.
23320 Defaults to @samp{"name"}.
23324 @deftypevr {@code{cgit-configuration} parameter} string cache-root
23325 Path used to store the cgit cache entries.
23327 Defaults to @samp{"/var/cache/cgit"}.
23331 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
23332 Number which specifies the time-to-live, in minutes, for the cached
23333 version of repository pages accessed with a fixed SHA1.
23335 Defaults to @samp{-1}.
23339 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
23340 Number which specifies the time-to-live, in minutes, for the cached
23341 version of repository pages accessed without a fixed SHA1.
23343 Defaults to @samp{5}.
23347 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
23348 Number which specifies the time-to-live, in minutes, for the cached
23349 version of the repository summary page.
23351 Defaults to @samp{5}.
23355 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
23356 Number which specifies the time-to-live, in minutes, for the cached
23357 version of the repository index page.
23359 Defaults to @samp{5}.
23363 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
23364 Number which specifies the time-to-live, in minutes, for the result of
23365 scanning a path for Git repositories.
23367 Defaults to @samp{15}.
23371 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
23372 Number which specifies the time-to-live, in minutes, for the cached
23373 version of the repository about page.
23375 Defaults to @samp{15}.
23379 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
23380 Number which specifies the time-to-live, in minutes, for the cached
23381 version of snapshots.
23383 Defaults to @samp{5}.
23387 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
23388 The maximum number of entries in the cgit cache. When set to @samp{0},
23389 caching is disabled.
23391 Defaults to @samp{0}.
23395 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
23396 Sort items in the repo list case sensitively.
23398 Defaults to @samp{#t}.
23402 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
23403 List of common prefixes which, when combined with a repository URL,
23404 generates valid clone URLs for the repository.
23406 Defaults to @samp{()}.
23410 @deftypevr {@code{cgit-configuration} parameter} list clone-url
23411 List of @code{clone-url} templates.
23413 Defaults to @samp{()}.
23417 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
23418 Command which will be invoked to format commit messages.
23420 Defaults to @samp{""}.
23424 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
23425 Flag which, when set to @samp{date}, enables strict date ordering in the
23426 commit log, and when set to @samp{topo} enables strict topological
23429 Defaults to @samp{"git log"}.
23433 @deftypevr {@code{cgit-configuration} parameter} file-object css
23434 URL which specifies the css document to include in all cgit pages.
23436 Defaults to @samp{"/share/cgit/cgit.css"}.
23440 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
23441 Specifies a command which will be invoked to format names and email
23442 address of committers, authors, and taggers, as represented in various
23443 places throughout the cgit interface.
23445 Defaults to @samp{""}.
23449 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
23450 Flag which, when set to @samp{#t}, will make cgit generate a HTML
23451 fragment suitable for embedding in other HTML pages.
23453 Defaults to @samp{#f}.
23457 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
23458 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
23459 commit history graph to the left of the commit messages in the
23460 repository log page.
23462 Defaults to @samp{#f}.
23466 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
23467 Flag which, when set to @samp{#t}, allows all filter settings to be
23468 overridden in repository-specific cgitrc files.
23470 Defaults to @samp{#f}.
23474 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
23475 Flag which, when set to @samp{#t}, allows users to follow a file in the
23478 Defaults to @samp{#f}.
23482 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
23483 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
23486 Defaults to @samp{#t}.
23490 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
23491 Flag which, when set to @samp{#t}, will make cgit generate extra links
23492 "summary", "commit", "tree" for each repo in the repository index.
23494 Defaults to @samp{#f}.
23498 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
23499 Flag which, when set to @samp{#t}, will make cgit display the owner of
23500 each repo in the repository index.
23502 Defaults to @samp{#t}.
23506 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
23507 Flag which, when set to @samp{#t}, will make cgit print the number of
23508 modified files for each commit on the repository log page.
23510 Defaults to @samp{#f}.
23514 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
23515 Flag which, when set to @samp{#t}, will make cgit print the number of
23516 added and removed lines for each commit on the repository log page.
23518 Defaults to @samp{#f}.
23522 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
23523 Flag which, when set to @code{#t}, will make cgit display remote
23524 branches in the summary and refs views.
23526 Defaults to @samp{#f}.
23530 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
23531 Flag which, when set to @code{1}, will make cgit use the subject of the
23532 parent commit as link text when generating links to parent commits in
23535 Defaults to @samp{#f}.
23539 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
23540 Flag which, when set to @samp{#t}, will make cgit use the subject of the
23541 parent commit as link text when generating links to parent commits in
23544 Defaults to @samp{#f}.
23548 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
23549 Flag which, when set to @samp{#t}, will make cgit generate linenumber
23550 links for plaintext blobs printed in the tree view.
23552 Defaults to @samp{#t}.
23556 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
23557 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
23558 set any repo specific settings.
23560 Defaults to @samp{#f}.
23564 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
23565 URL used as link to a shortcut icon for cgit.
23567 Defaults to @samp{"/favicon.ico"}.
23571 @deftypevr {@code{cgit-configuration} parameter} string footer
23572 The content of the file specified with this option will be included
23573 verbatim at the bottom of all pages (i.e.@: it replaces the standard
23574 "generated by..."@: message).
23576 Defaults to @samp{""}.
23580 @deftypevr {@code{cgit-configuration} parameter} string head-include
23581 The content of the file specified with this option will be included
23582 verbatim in the HTML HEAD section on all pages.
23584 Defaults to @samp{""}.
23588 @deftypevr {@code{cgit-configuration} parameter} string header
23589 The content of the file specified with this option will be included
23590 verbatim at the top of all pages.
23592 Defaults to @samp{""}.
23596 @deftypevr {@code{cgit-configuration} parameter} file-object include
23597 Name of a configfile to include before the rest of the current config-
23600 Defaults to @samp{""}.
23604 @deftypevr {@code{cgit-configuration} parameter} string index-header
23605 The content of the file specified with this option will be included
23606 verbatim above the repository index.
23608 Defaults to @samp{""}.
23612 @deftypevr {@code{cgit-configuration} parameter} string index-info
23613 The content of the file specified with this option will be included
23614 verbatim below the heading on the repository index page.
23616 Defaults to @samp{""}.
23620 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
23621 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
23622 in the servers timezone.
23624 Defaults to @samp{#f}.
23628 @deftypevr {@code{cgit-configuration} parameter} file-object logo
23629 URL which specifies the source of an image which will be used as a logo
23632 Defaults to @samp{"/share/cgit/cgit.png"}.
23636 @deftypevr {@code{cgit-configuration} parameter} string logo-link
23637 URL loaded when clicking on the cgit logo image.
23639 Defaults to @samp{""}.
23643 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
23644 Command which will be invoked to format the Owner column of the main
23647 Defaults to @samp{""}.
23651 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
23652 Number of items to display in atom feeds view.
23654 Defaults to @samp{10}.
23658 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
23659 Number of entries to list per page in "log" view.
23661 Defaults to @samp{50}.
23665 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
23666 Number of commit message characters to display in "log" view.
23668 Defaults to @samp{80}.
23672 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
23673 Specifies the number of entries to list per page on the repository index
23676 Defaults to @samp{50}.
23680 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
23681 Specifies the maximum number of repo description characters to display
23682 on the repository index page.
23684 Defaults to @samp{80}.
23688 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
23689 Specifies the maximum size of a blob to display HTML for in KBytes.
23691 Defaults to @samp{0}.
23695 @deftypevr {@code{cgit-configuration} parameter} string max-stats
23696 Maximum statistics period. Valid values are @samp{week},@samp{month},
23697 @samp{quarter} and @samp{year}.
23699 Defaults to @samp{""}.
23703 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
23704 Mimetype for the specified filename extension.
23706 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
23707 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
23708 "image/png") (svg "image/svg+xml"))}.
23712 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
23713 Specifies the file to use for automatic mimetype lookup.
23715 Defaults to @samp{""}.
23719 @deftypevr {@code{cgit-configuration} parameter} string module-link
23720 Text which will be used as the formatstring for a hyperlink when a
23721 submodule is printed in a directory listing.
23723 Defaults to @samp{""}.
23727 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
23728 If set to the value @samp{#t} caching will be disabled.
23730 Defaults to @samp{#f}.
23734 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
23735 If set to @samp{#t} showing full author email addresses will be
23738 Defaults to @samp{#f}.
23742 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
23743 Flag which, when set to @samp{#t}, will make cgit omit the standard
23744 header on all pages.
23746 Defaults to @samp{#f}.
23750 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
23751 A list of subdirectories inside of @code{repository-directory}, relative
23752 to it, that should loaded as Git repositories. An empty list means that
23753 all subdirectories will be loaded.
23755 Defaults to @samp{()}.
23759 @deftypevr {@code{cgit-configuration} parameter} file-object readme
23760 Text which will be used as default value for @code{cgit-repo-readme}.
23762 Defaults to @samp{""}.
23766 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
23767 If set to @code{#t} and @code{repository-directory} is enabled, if any
23768 repositories are found with a suffix of @code{.git}, this suffix will be
23769 removed for the URL and name.
23771 Defaults to @samp{#f}.
23775 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
23776 Maximum number of files to consider when detecting renames.
23778 Defaults to @samp{-1}.
23782 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
23783 The way in which repositories in each section are sorted.
23785 Defaults to @samp{""}.
23789 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
23790 Text used as content for the @code{robots} meta-tag.
23792 Defaults to @samp{("noindex" "nofollow")}.
23796 @deftypevr {@code{cgit-configuration} parameter} string root-desc
23797 Text printed below the heading on the repository index page.
23799 Defaults to @samp{"a fast webinterface for the git dscm"}.
23803 @deftypevr {@code{cgit-configuration} parameter} string root-readme
23804 The content of the file specified with this option will be included
23805 verbatim below thef "about" link on the repository index page.
23807 Defaults to @samp{""}.
23811 @deftypevr {@code{cgit-configuration} parameter} string root-title
23812 Text printed as heading on the repository index page.
23814 Defaults to @samp{""}.
23818 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
23819 If set to @samp{#t} and repository-directory is enabled,
23820 repository-directory will recurse into directories whose name starts
23821 with a period. Otherwise, repository-directory will stay away from such
23822 directories, considered as "hidden". Note that this does not apply to
23823 the ".git" directory in non-bare repos.
23825 Defaults to @samp{#f}.
23829 @deftypevr {@code{cgit-configuration} parameter} list snapshots
23830 Text which specifies the default set of snapshot formats that cgit
23831 generates links for.
23833 Defaults to @samp{()}.
23837 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
23838 Name of the directory to scan for repositories (represents
23841 Defaults to @samp{"/srv/git"}.
23845 @deftypevr {@code{cgit-configuration} parameter} string section
23846 The name of the current repository section - all repositories defined
23847 after this option will inherit the current section name.
23849 Defaults to @samp{""}.
23853 @deftypevr {@code{cgit-configuration} parameter} string section-sort
23854 Flag which, when set to @samp{1}, will sort the sections on the
23855 repository listing by name.
23857 Defaults to @samp{""}.
23861 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
23862 A number which, if defined prior to repository-directory, specifies how
23863 many path elements from each repo path to use as a default section name.
23865 Defaults to @samp{0}.
23869 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
23870 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
23873 Defaults to @samp{#f}.
23877 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
23878 Specifies a command which will be invoked to format plaintext blobs in
23881 Defaults to @samp{""}.
23885 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
23886 Specifies the number of branches to display in the repository "summary"
23889 Defaults to @samp{10}.
23893 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
23894 Specifies the number of log entries to display in the repository
23897 Defaults to @samp{10}.
23901 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
23902 Specifies the number of tags to display in the repository "summary"
23905 Defaults to @samp{10}.
23909 @deftypevr {@code{cgit-configuration} parameter} string strict-export
23910 Filename which, if specified, needs to be present within the repository
23911 for cgit to allow access to that repository.
23913 Defaults to @samp{""}.
23917 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
23918 URL which, if specified, will be used as root for all cgit links.
23920 Defaults to @samp{"/"}.
23924 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
23925 A list of @dfn{cgit-repo} records to use with config.
23927 Defaults to @samp{()}.
23929 Available @code{repository-cgit-configuration} fields are:
23931 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
23932 A mask of snapshot formats for this repo that cgit generates links for,
23933 restricted by the global @code{snapshots} setting.
23935 Defaults to @samp{()}.
23939 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
23940 Override the default @code{source-filter}.
23942 Defaults to @samp{""}.
23946 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
23947 The relative URL used to access the repository.
23949 Defaults to @samp{""}.
23953 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
23954 Override the default @code{about-filter}.
23956 Defaults to @samp{""}.
23960 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
23961 Flag which, when set to @samp{age}, enables date ordering in the branch
23962 ref list, and when set to @samp{name} enables ordering by branch name.
23964 Defaults to @samp{""}.
23968 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
23969 A list of URLs which can be used to clone repo.
23971 Defaults to @samp{()}.
23975 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
23976 Override the default @code{commit-filter}.
23978 Defaults to @samp{""}.
23982 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
23983 Flag which, when set to @samp{date}, enables strict date ordering in the
23984 commit log, and when set to @samp{topo} enables strict topological
23987 Defaults to @samp{""}.
23991 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
23992 The name of the default branch for this repository. If no such branch
23993 exists in the repository, the first branch name (when sorted) is used as
23994 default instead. By default branch pointed to by HEAD, or "master" if
23995 there is no suitable HEAD.
23997 Defaults to @samp{""}.
24001 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
24002 The value to show as repository description.
24004 Defaults to @samp{""}.
24008 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
24009 The value to show as repository homepage.
24011 Defaults to @samp{""}.
24015 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
24016 Override the default @code{email-filter}.
24018 Defaults to @samp{""}.
24022 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
24023 A flag which can be used to disable the global setting
24024 @code{enable-commit-graph?}.
24026 Defaults to @samp{disabled}.
24030 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
24031 A flag which can be used to disable the global setting
24032 @code{enable-log-filecount?}.
24034 Defaults to @samp{disabled}.
24038 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
24039 A flag which can be used to disable the global setting
24040 @code{enable-log-linecount?}.
24042 Defaults to @samp{disabled}.
24046 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
24047 Flag which, when set to @code{#t}, will make cgit display remote
24048 branches in the summary and refs views.
24050 Defaults to @samp{disabled}.
24054 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
24055 A flag which can be used to override the global setting
24056 @code{enable-subject-links?}.
24058 Defaults to @samp{disabled}.
24062 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
24063 A flag which can be used to override the global setting
24064 @code{enable-html-serving?}.
24066 Defaults to @samp{disabled}.
24070 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
24071 Flag which, when set to @code{#t}, hides the repository from the
24074 Defaults to @samp{#f}.
24078 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
24079 Flag which, when set to @samp{#t}, ignores the repository.
24081 Defaults to @samp{#f}.
24085 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
24086 URL which specifies the source of an image which will be used as a logo
24087 on this repo’s pages.
24089 Defaults to @samp{""}.
24093 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
24094 URL loaded when clicking on the cgit logo image.
24096 Defaults to @samp{""}.
24100 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
24101 Override the default @code{owner-filter}.
24103 Defaults to @samp{""}.
24107 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
24108 Text which will be used as the formatstring for a hyperlink when a
24109 submodule is printed in a directory listing. The arguments for the
24110 formatstring are the path and SHA1 of the submodule commit.
24112 Defaults to @samp{""}.
24116 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
24117 Text which will be used as the formatstring for a hyperlink when a
24118 submodule with the specified subdirectory path is printed in a directory
24121 Defaults to @samp{()}.
24125 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
24126 Override the default maximum statistics period.
24128 Defaults to @samp{""}.
24132 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
24133 The value to show as repository name.
24135 Defaults to @samp{""}.
24139 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
24140 A value used to identify the owner of the repository.
24142 Defaults to @samp{""}.
24146 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
24147 An absolute path to the repository directory.
24149 Defaults to @samp{""}.
24153 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
24154 A path (relative to repo) which specifies a file to include verbatim as
24155 the "About" page for this repo.
24157 Defaults to @samp{""}.
24161 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
24162 The name of the current repository section - all repositories defined
24163 after this option will inherit the current section name.
24165 Defaults to @samp{""}.
24169 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
24170 Extra options will be appended to cgitrc file.
24172 Defaults to @samp{()}.
24178 @deftypevr {@code{cgit-configuration} parameter} list extra-options
24179 Extra options will be appended to cgitrc file.
24181 Defaults to @samp{()}.
24186 @c %end of fragment
24188 However, it could be that you just want to get a @code{cgitrc} up and
24189 running. In that case, you can pass an @code{opaque-cgit-configuration}
24190 as a record to @code{cgit-service-type}. As its name indicates, an
24191 opaque configuration does not have easy reflective capabilities.
24193 Available @code{opaque-cgit-configuration} fields are:
24195 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
24199 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
24200 The contents of the @code{cgitrc}, as a string.
24203 For example, if your @code{cgitrc} is just the empty string, you
24204 could instantiate a cgit service like this:
24207 (service cgit-service-type
24208 (opaque-cgit-configuration
24212 @subsubheading Gitolite Service
24214 @cindex Gitolite service
24215 @cindex Git, hosting
24216 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
24217 repositories on a central server.
24219 Gitolite can handle multiple repositories and users, and supports flexible
24220 configuration of the permissions for the users on the repositories.
24222 The following example will configure Gitolite using the default @code{git}
24223 user, and the provided SSH public key.
24226 (service gitolite-service-type
24227 (gitolite-configuration
24228 (admin-pubkey (plain-file
24230 "ssh-rsa AAAA... guix@@example.com"))))
24233 Gitolite is configured through a special admin repository which you can clone,
24234 for example, if you setup Gitolite on @code{example.com}, you would run the
24235 following command to clone the admin repository.
24238 git clone git@@example.com:gitolite-admin
24241 When the Gitolite service is activated, the provided @code{admin-pubkey} will
24242 be inserted in to the @file{keydir} directory in the gitolite-admin
24243 repository. If this results in a change in the repository, it will be
24244 committed using the message ``gitolite setup by GNU Guix''.
24246 @deftp {Data Type} gitolite-configuration
24247 Data type representing the configuration for @code{gitolite-service-type}.
24250 @item @code{package} (default: @var{gitolite})
24251 Gitolite package to use.
24253 @item @code{user} (default: @var{git})
24254 User to use for Gitolite. This will be user that you use when accessing
24257 @item @code{group} (default: @var{git})
24258 Group to use for Gitolite.
24260 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
24261 Directory in which to store the Gitolite configuration and repositories.
24263 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
24264 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
24265 representing the configuration for Gitolite.
24267 @item @code{admin-pubkey} (default: @var{#f})
24268 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
24269 setup Gitolite. This will be inserted in to the @file{keydir} directory
24270 within the gitolite-admin repository.
24272 To specify the SSH key as a string, use the @code{plain-file} function.
24275 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
24281 @deftp {Data Type} gitolite-rc-file
24282 Data type representing the Gitolite RC file.
24285 @item @code{umask} (default: @code{#o0077})
24286 This controls the permissions Gitolite sets on the repositories and their
24289 A value like @code{#o0027} will give read access to the group used by Gitolite
24290 (by default: @code{git}). This is necessary when using Gitolite with software
24291 like cgit or gitweb.
24293 @item @code{git-config-keys} (default: @code{""})
24294 Gitolite allows you to set git config values using the "config" keyword. This
24295 setting allows control over the config keys to accept.
24297 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
24298 Set the role names allowed to be used by users running the perms command.
24300 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
24301 This setting controls the commands and features to enable within Gitolite.
24307 @node Game Services
24308 @subsection Game Services
24310 @subsubheading The Battle for Wesnoth Service
24312 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
24313 based tactical strategy game, with several single player campaigns, and
24314 multiplayer games (both networked and local).
24316 @defvar {Scheme Variable} wesnothd-service-type
24317 Service type for the wesnothd service. Its value must be a
24318 @code{wesnothd-configuration} object. To run wesnothd in the default
24319 configuration, instantiate it as:
24322 (service wesnothd-service-type)
24326 @deftp {Data Type} wesnothd-configuration
24327 Data type representing the configuration of @command{wesnothd}.
24330 @item @code{package} (default: @code{wesnoth-server})
24331 The wesnoth server package to use.
24333 @item @code{port} (default: @code{15000})
24334 The port to bind the server to.
24339 @node Guix Services
24340 @subsection Guix Services
24342 @subsubheading Guix Data Service
24343 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
24344 and provides data about GNU Guix. This includes information about
24345 packages, derivations and lint warnings.
24347 The data is stored in a PostgreSQL database, and available through a web
24350 @defvar {Scheme Variable} guix-data-service-type
24351 Service type for the Guix Data Service. Its value must be a
24352 @code{guix-data-service-configuration} object. The service optionally
24353 extends the getmail service, as the guix-commits mailing list is used to
24354 find out about changes in the Guix git repository.
24357 @deftp {Data Type} guix-data-service-configuration
24358 Data type representing the configuration of the Guix Data Service.
24361 @item @code{package} (default: @code{guix-data-service})
24362 The Guix Data Service package to use.
24364 @item @code{user} (default: @code{"guix-data-service"})
24365 The system user to run the service as.
24367 @item @code{group} (default: @code{"guix-data-service"})
24368 The system group to run the service as.
24370 @item @code{port} (default: @code{8765})
24371 The port to bind the web service to.
24373 @item @code{host} (default: @code{"127.0.0.1"})
24374 The host to bind the web service to.
24376 @item @code{getmail-idle-mailboxes} (default: @code{#f})
24377 If set, this is the list of mailboxes that the getmail service will be
24378 configured to listen to.
24380 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
24381 If set, this is the @code{getmail-retriever-configuration} object with
24382 which to configure getmail to fetch mail from the guix-commits mailing
24389 @node Miscellaneous Services
24390 @subsection Miscellaneous Services
24392 @cindex fingerprint
24393 @subsubheading Fingerprint Service
24395 The @code{(gnu services authentication)} module provides a DBus service to
24396 read and identify fingerprints via a fingerprint sensor.
24398 @defvr {Scheme Variable} fprintd-service-type
24399 The service type for @command{fprintd}, which provides the fingerprint
24400 reading capability.
24403 (service fprintd-service-type)
24408 @subsubheading System Control Service
24410 The @code{(gnu services sysctl)} provides a service to configure kernel
24411 parameters at boot.
24413 @defvr {Scheme Variable} sysctl-service-type
24414 The service type for @command{sysctl}, which modifies kernel parameters
24415 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
24419 (service sysctl-service-type
24420 (sysctl-configuration
24421 (settings '(("net.ipv4.ip_forward" . "1")))))
24425 @deftp {Data Type} sysctl-configuration
24426 The data type representing the configuration of @command{sysctl}.
24429 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
24430 The @command{sysctl} executable to use.
24432 @item @code{settings} (default: @code{'()})
24433 An association list specifies kernel parameters and their values.
24438 @subsubheading PC/SC Smart Card Daemon Service
24440 The @code{(gnu services security-token)} module provides the following service
24441 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
24442 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
24443 manager that coordinates communications with smart card readers, smart cards
24444 and cryptographic tokens that are connected to the system.
24446 @defvr {Scheme Variable} pcscd-service-type
24447 Service type for the @command{pcscd} service. Its value must be a
24448 @code{pcscd-configuration} object. To run pcscd in the default
24449 configuration, instantiate it as:
24452 (service pcscd-service-type)
24456 @deftp {Data Type} pcscd-configuration
24457 The data type representing the configuration of @command{pcscd}.
24460 @item @code{pcsc-lite} (default: @code{pcsc-lite})
24461 The pcsc-lite package that provides pcscd.
24462 @item @code{usb-drivers} (default: @code{(list ccid)})
24463 List of packages that provide USB drivers to pcscd. Drivers are expected to be
24464 under @file{pcsc/drivers} in the store directory of the package.
24469 @subsubheading Lirc Service
24471 The @code{(gnu services lirc)} module provides the following service.
24473 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
24474 [#:device #f] [#:driver #f] [#:config-file #f] @
24475 [#:extra-options '()]
24476 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
24477 decodes infrared signals from remote controls.
24479 Optionally, @var{device}, @var{driver} and @var{config-file}
24480 (configuration file name) may be specified. See @command{lircd} manual
24483 Finally, @var{extra-options} is a list of additional command-line options
24484 passed to @command{lircd}.
24488 @subsubheading Spice Service
24490 The @code{(gnu services spice)} module provides the following service.
24492 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
24493 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
24494 that enables sharing the clipboard with a vm and setting the guest display
24495 resolution when the graphical console window resizes.
24498 @cindex inputattach
24499 @subsubheading inputattach Service
24501 @cindex tablet input, for Xorg
24502 @cindex touchscreen input, for Xorg
24503 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
24504 use input devices such as Wacom tablets, touchscreens, or joysticks with the
24505 Xorg display server.
24507 @deffn {Scheme Variable} inputattach-service-type
24508 Type of a service that runs @command{inputattach} on a device and
24509 dispatches events from it.
24512 @deftp {Data Type} inputattach-configuration
24514 @item @code{device-type} (default: @code{"wacom"})
24515 The type of device to connect to. Run @command{inputattach --help}, from the
24516 @code{inputattach} package, to see the list of supported device types.
24518 @item @code{device} (default: @code{"/dev/ttyS0"})
24519 The device file to connect to the device.
24521 @item @code{log-file} (default: @code{#f})
24522 If true, this must be the name of a file to log messages to.
24526 @subsection Dictionary Services
24528 The @code{(gnu services dict)} module provides the following service:
24530 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
24531 Return a service that runs the @command{dicod} daemon, an implementation
24532 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
24534 The optional @var{config} argument specifies the configuration for
24535 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
24536 default it serves the GNU Collaborative International Dictonary of English.
24538 You can add @command{open localhost} to your @file{~/.dico} file to make
24539 @code{localhost} the default server for @command{dico} client
24540 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
24543 @deftp {Data Type} dicod-configuration
24544 Data type representing the configuration of dicod.
24547 @item @code{dico} (default: @var{dico})
24548 Package object of the GNU Dico dictionary server.
24550 @item @code{interfaces} (default: @var{'("localhost")})
24551 This is the list of IP addresses and ports and possibly socket file
24552 names to listen to (@pxref{Server Settings, @code{listen} directive,,
24553 dico, GNU Dico Manual}).
24555 @item @code{handlers} (default: @var{'()})
24556 List of @code{<dicod-handler>} objects denoting handlers (module instances).
24558 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
24559 List of @code{<dicod-database>} objects denoting dictionaries to be served.
24563 @deftp {Data Type} dicod-handler
24564 Data type representing a dictionary handler (module instance).
24568 Name of the handler (module instance).
24570 @item @code{module} (default: @var{#f})
24571 Name of the dicod module of the handler (instance). If it is @code{#f},
24572 the module has the same name as the handler.
24573 (@pxref{Modules,,, dico, GNU Dico Manual}).
24575 @item @code{options}
24576 List of strings or gexps representing the arguments for the module handler
24580 @deftp {Data Type} dicod-database
24581 Data type representing a dictionary database.
24585 Name of the database, will be used in DICT commands.
24587 @item @code{handler}
24588 Name of the dicod handler (module instance) used by this database
24589 (@pxref{Handlers,,, dico, GNU Dico Manual}).
24591 @item @code{complex?} (default: @var{#f})
24592 Whether the database configuration complex. The complex configuration
24593 will need a corresponding @code{<dicod-handler>} object, otherwise not.
24595 @item @code{options}
24596 List of strings or gexps representing the arguments for the database
24597 (@pxref{Databases,,, dico, GNU Dico Manual}).
24601 @defvr {Scheme Variable} %dicod-database:gcide
24602 A @code{<dicod-database>} object serving the GNU Collaborative International
24603 Dictionary of English using the @code{gcide} package.
24606 The following is an example @code{dicod-service} configuration.
24609 (dicod-service #:config
24610 (dicod-configuration
24611 (handlers (list (dicod-handler
24615 (list #~(string-append "dbdir=" #$wordnet))))))
24616 (databases (list (dicod-database
24619 (handler "wordnet")
24620 (options '("database=wn")))
24621 %dicod-database:gcide))))
24625 @subsubheading Docker Service
24627 The @code{(gnu services docker)} module provides the following services.
24629 @defvr {Scheme Variable} docker-service-type
24631 This is the type of the service that runs @url{https://www.docker.com,Docker},
24632 a daemon that can execute application bundles (sometimes referred to as
24633 ``containers'') in isolated environments.
24637 @deftp {Data Type} docker-configuration
24638 This is the data type representing the configuration of Docker and Containerd.
24642 @item @code{package} (default: @code{docker})
24643 The Docker package to use.
24645 @item @code{containerd} (default: @var{containerd})
24646 The Containerd package to use.
24652 @subsubheading Auditd Service
24654 The @code{(gnu services auditd)} module provides the following service.
24656 @defvr {Scheme Variable} auditd-service-type
24658 This is the type of the service that runs
24659 @url{https://people.redhat.com/sgrubb/audit/,auditd},
24660 a daemon that tracks security-relevant information on your system.
24662 Examples of things that can be tracked:
24672 Failed login attempts
24679 @command{auditctl} from the @code{audit} package can be used in order
24680 to add or remove events to be tracked (until the next reboot).
24681 In order to permanently track events, put the command line arguments
24682 of auditctl into @file{/etc/audit/audit.rules}.
24683 @command{aureport} from the @code{audit} package can be used in order
24684 to view a report of all recorded events.
24685 The audit daemon usually logs into the directory @file{/var/log/audit}.
24689 @deftp {Data Type} auditd-configuration
24690 This is the data type representing the configuration of auditd.
24694 @item @code{audit} (default: @code{audit})
24695 The audit package to use.
24700 @defvr {Scheme Variable} singularity-service-type
24701 This is the type of the service that allows you to run
24702 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
24703 create and run application bundles (aka. ``containers''). The value for this
24704 service is the Singularity package to use.
24706 The service does not install a daemon; instead, it installs helper programs as
24707 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
24708 @command{singularity run} and similar commands.
24712 @subsubheading Nix service
24714 The @code{(gnu services nix)} module provides the following service.
24716 @defvr {Scheme Variable} nix-service-type
24718 This is the type of the service that runs build daemon of the
24719 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
24723 (use-modules (gnu))
24724 (use-service-modules nix)
24725 (use-package-modules package-management)
24729 (packages (append (list nix)
24732 (services (append (list (service nix-service-type))
24736 After @command{guix system reconfigure} configure Nix for your user:
24739 @item Add a Nix channel and update it. See
24740 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
24742 @item Create a symlink to your profile and activate Nix profile:
24746 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
24747 $ source /run/current-system/profile/etc/profile.d/nix.sh
24752 @node Setuid Programs
24753 @section Setuid Programs
24755 @cindex setuid programs
24756 Some programs need to run with ``root'' privileges, even when they are
24757 launched by unprivileged users. A notorious example is the
24758 @command{passwd} program, which users can run to change their
24759 password, and which needs to access the @file{/etc/passwd} and
24760 @file{/etc/shadow} files---something normally restricted to root, for
24761 obvious security reasons. To address that, these executables are
24762 @dfn{setuid-root}, meaning that they always run with root privileges
24763 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
24764 for more info about the setuid mechanism.)
24766 The store itself @emph{cannot} contain setuid programs: that would be a
24767 security issue since any user on the system can write derivations that
24768 populate the store (@pxref{The Store}). Thus, a different mechanism is
24769 used: instead of changing the setuid bit directly on files that are in
24770 the store, we let the system administrator @emph{declare} which programs
24771 should be setuid root.
24773 The @code{setuid-programs} field of an @code{operating-system}
24774 declaration contains a list of G-expressions denoting the names of
24775 programs to be setuid-root (@pxref{Using the Configuration System}).
24776 For instance, the @command{passwd} program, which is part of the Shadow
24777 package, can be designated by this G-expression (@pxref{G-Expressions}):
24780 #~(string-append #$shadow "/bin/passwd")
24783 A default set of setuid programs is defined by the
24784 @code{%setuid-programs} variable of the @code{(gnu system)} module.
24786 @defvr {Scheme Variable} %setuid-programs
24787 A list of G-expressions denoting common programs that are setuid-root.
24789 The list includes commands such as @command{passwd}, @command{ping},
24790 @command{su}, and @command{sudo}.
24793 Under the hood, the actual setuid programs are created in the
24794 @file{/run/setuid-programs} directory at system activation time. The
24795 files in this directory refer to the ``real'' binaries, which are in the
24798 @node X.509 Certificates
24799 @section X.509 Certificates
24801 @cindex HTTPS, certificates
24802 @cindex X.509 certificates
24804 Web servers available over HTTPS (that is, HTTP over the transport-layer
24805 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
24806 that the client can then use to @emph{authenticate} the server. To do
24807 that, clients verify that the server's certificate is signed by a
24808 so-called @dfn{certificate authority} (CA). But to verify the CA's
24809 signature, clients must have first acquired the CA's certificate.
24811 Web browsers such as GNU@tie{}IceCat include their own set of CA
24812 certificates, such that they are able to verify CA signatures
24815 However, most other programs that can talk HTTPS---@command{wget},
24816 @command{git}, @command{w3m}, etc.---need to be told where CA
24817 certificates can be found.
24819 @cindex @code{nss-certs}
24820 In Guix, this is done by adding a package that provides certificates
24821 to the @code{packages} field of the @code{operating-system} declaration
24822 (@pxref{operating-system Reference}). Guix includes one such package,
24823 @code{nss-certs}, which is a set of CA certificates provided as part of
24824 Mozilla's Network Security Services.
24826 Note that it is @emph{not} part of @code{%base-packages}, so you need to
24827 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
24828 most applications and libraries look for certificates by default, points
24829 to the certificates installed globally.
24831 Unprivileged users, including users of Guix on a foreign distro,
24832 can also install their own certificate package in
24833 their profile. A number of environment variables need to be defined so
24834 that applications and libraries know where to find them. Namely, the
24835 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
24836 variables. Some applications add their own environment variables; for
24837 instance, the Git version control system honors the certificate bundle
24838 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
24839 would typically run something like:
24842 $ guix install nss-certs
24843 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
24844 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24845 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
24848 As another example, R requires the @code{CURL_CA_BUNDLE} environment
24849 variable to point to a certificate bundle, so you would have to run
24850 something like this:
24853 $ guix install nss-certs
24854 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24857 For other applications you may want to look up the required environment
24858 variable in the relevant documentation.
24861 @node Name Service Switch
24862 @section Name Service Switch
24864 @cindex name service switch
24866 The @code{(gnu system nss)} module provides bindings to the
24867 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
24868 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
24869 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
24870 extended with new ``name'' lookup methods for system databases, which
24871 includes host names, service names, user accounts, and more (@pxref{Name
24872 Service Switch, System Databases and Name Service Switch,, libc, The GNU
24873 C Library Reference Manual}).
24875 The NSS configuration specifies, for each system database, which lookup
24876 method is to be used, and how the various methods are chained
24877 together---for instance, under which circumstances NSS should try the
24878 next method in the list. The NSS configuration is given in the
24879 @code{name-service-switch} field of @code{operating-system} declarations
24880 (@pxref{operating-system Reference, @code{name-service-switch}}).
24883 @cindex .local, host name lookup
24884 As an example, the declaration below configures the NSS to use the
24885 @uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
24886 back-end}, which supports host name lookups over multicast DNS (mDNS)
24887 for host names ending in @code{.local}:
24890 (name-service-switch
24891 (hosts (list %files ;first, check /etc/hosts
24893 ;; If the above did not succeed, try
24894 ;; with 'mdns_minimal'.
24896 (name "mdns_minimal")
24898 ;; 'mdns_minimal' is authoritative for
24899 ;; '.local'. When it returns "not found",
24900 ;; no need to try the next methods.
24901 (reaction (lookup-specification
24902 (not-found => return))))
24904 ;; Then fall back to DNS.
24908 ;; Finally, try with the "full" 'mdns'.
24913 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
24914 contains this configuration, so you will not have to type it if all you
24915 want is to have @code{.local} host lookup working.
24917 Note that, in this case, in addition to setting the
24918 @code{name-service-switch} of the @code{operating-system} declaration,
24919 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
24920 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
24921 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
24922 to the name service cache daemon (@pxref{Base Services,
24923 @code{nscd-service}}).
24925 For convenience, the following variables provide typical NSS
24928 @defvr {Scheme Variable} %default-nss
24929 This is the default name service switch configuration, a
24930 @code{name-service-switch} object.
24933 @defvr {Scheme Variable} %mdns-host-lookup-nss
24934 This is the name service switch configuration with support for host name
24935 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
24938 The reference for name service switch configuration is given below. It
24939 is a direct mapping of the configuration file format of the C library , so
24940 please refer to the C library manual for more information (@pxref{NSS
24941 Configuration File,,, libc, The GNU C Library Reference Manual}).
24942 Compared to the configuration file format of libc NSS, it has the advantage
24943 not only of adding this warm parenthetic feel that we like, but also
24944 static checks: you will know about syntax errors and typos as soon as you
24945 run @command{guix system}.
24947 @deftp {Data Type} name-service-switch
24949 This is the data type representation the configuration of libc's name
24950 service switch (NSS). Each field below represents one of the supported
24967 The system databases handled by the NSS. Each of these fields must be a
24968 list of @code{<name-service>} objects (see below).
24972 @deftp {Data Type} name-service
24974 This is the data type representing an actual name service and the
24975 associated lookup action.
24979 A string denoting the name service (@pxref{Services in the NSS
24980 configuration,,, libc, The GNU C Library Reference Manual}).
24982 Note that name services listed here must be visible to nscd. This is
24983 achieved by passing the @code{#:name-services} argument to
24984 @code{nscd-service} the list of packages providing the needed name
24985 services (@pxref{Base Services, @code{nscd-service}}).
24988 An action specified using the @code{lookup-specification} macro
24989 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
24990 Reference Manual}). For example:
24993 (lookup-specification (unavailable => continue)
24994 (success => return))
24999 @node Initial RAM Disk
25000 @section Initial RAM Disk
25003 @cindex initial RAM disk
25004 For bootstrapping purposes, the Linux-Libre kernel is passed an
25005 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
25006 root file system as well as an initialization script. The latter is
25007 responsible for mounting the real root file system, and for loading any
25008 kernel modules that may be needed to achieve that.
25010 The @code{initrd-modules} field of an @code{operating-system}
25011 declaration allows you to specify Linux-libre kernel modules that must
25012 be available in the initrd. In particular, this is where you would list
25013 modules needed to actually drive the hard disk where your root partition
25014 is---although the default value of @code{initrd-modules} should cover
25015 most use cases. For example, assuming you need the @code{megaraid_sas}
25016 module in addition to the default modules to be able to access your root
25017 file system, you would write:
25022 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
25025 @defvr {Scheme Variable} %base-initrd-modules
25026 This is the list of kernel modules included in the initrd by default.
25029 Furthermore, if you need lower-level customization, the @code{initrd}
25030 field of an @code{operating-system} declaration allows
25031 you to specify which initrd you would like to use. The @code{(gnu
25032 system linux-initrd)} module provides three ways to build an initrd: the
25033 high-level @code{base-initrd} procedure and the low-level
25034 @code{raw-initrd} and @code{expression->initrd} procedures.
25036 The @code{base-initrd} procedure is intended to cover most common uses.
25037 For example, if you want to add a bunch of kernel modules to be loaded
25038 at boot time, you can define the @code{initrd} field of the operating
25039 system declaration like this:
25042 (initrd (lambda (file-systems . rest)
25043 ;; Create a standard initrd but set up networking
25044 ;; with the parameters QEMU expects by default.
25045 (apply base-initrd file-systems
25046 #:qemu-networking? #t
25050 The @code{base-initrd} procedure also handles common use cases that
25051 involves using the system as a QEMU guest, or as a ``live'' system with
25052 volatile root file system.
25054 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
25055 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
25056 such as trying to guess which kernel modules and packages should be included
25057 to the initrd. An example use of @code{raw-initrd} is when a user has
25058 a custom Linux kernel configuration and default kernel modules included by
25059 @code{base-initrd} are not available.
25061 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
25062 honors several options passed on the Linux kernel command line
25063 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
25064 @code{-append} option of QEMU), notably:
25067 @item --load=@var{boot}
25068 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
25069 program, once it has mounted the root file system.
25071 Guix uses this option to yield control to a boot program that runs the
25072 service activation programs and then spawns the GNU@tie{}Shepherd, the
25073 initialization system.
25075 @item --root=@var{root}
25076 Mount @var{root} as the root file system. @var{root} can be a
25077 device name like @code{/dev/sda1}, a file system label, or a file system
25080 @item --system=@var{system}
25081 Have @file{/run/booted-system} and @file{/run/current-system} point to
25084 @item modprobe.blacklist=@var{modules}@dots{}
25085 @cindex module, black-listing
25086 @cindex black list, of kernel modules
25087 Instruct the initial RAM disk as well as the @command{modprobe} command
25088 (from the kmod package) to refuse to load @var{modules}. @var{modules}
25089 must be a comma-separated list of module names---e.g.,
25090 @code{usbkbd,9pnet}.
25093 Start a read-eval-print loop (REPL) from the initial RAM disk before it
25094 tries to load kernel modules and to mount the root file system. Our
25095 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
25096 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
25097 Manual}, for more information on Guile's REPL.
25101 Now that you know all the features that initial RAM disks produced by
25102 @code{base-initrd} and @code{raw-initrd} provide,
25103 here is how to use it and customize it further.
25106 @cindex initial RAM disk
25107 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
25108 [#:linux-modules '()] [#:mapped-devices '()] @
25109 [#:keyboard-layout #f] @
25110 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
25111 Return a derivation that builds a raw initrd. @var{file-systems} is
25112 a list of file systems to be mounted by the initrd, possibly in addition to
25113 the root file system specified on the kernel command line via @code{--root}.
25114 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
25115 @var{mapped-devices} is a list of device mappings to realize before
25116 @var{file-systems} are mounted (@pxref{Mapped Devices}).
25117 @var{helper-packages} is a list of packages to be copied in the initrd. It may
25118 include @code{e2fsck/static} or other packages needed by the initrd to check
25119 the root file system.
25121 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
25122 the desired console keyboard layout. This is done before @var{mapped-devices}
25123 are set up and before @var{file-systems} are mounted such that, should the
25124 user need to enter a passphrase or use the REPL, this happens using the
25125 intended keyboard layout.
25127 When @var{qemu-networking?} is true, set up networking with the standard QEMU
25128 parameters. When @var{virtio?} is true, load additional modules so that the
25129 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
25131 When @var{volatile-root?} is true, the root file system is writable but any changes
25135 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
25136 [#:mapped-devices '()] [#:keyboard-layout #f] @
25137 [#:qemu-networking? #f] [#:volatile-root? #f] @
25138 [#:linux-modules '()]
25139 Return as a file-like object a generic initrd, with kernel
25140 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
25141 mounted by the initrd, possibly in addition to the root file system specified
25142 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
25143 mappings to realize before @var{file-systems} are mounted.
25145 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
25146 the desired console keyboard layout. This is done before @var{mapped-devices}
25147 are set up and before @var{file-systems} are mounted such that, should the
25148 user need to enter a passphrase or use the REPL, this happens using the
25149 intended keyboard layout.
25151 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
25153 The initrd is automatically populated with all the kernel modules necessary
25154 for @var{file-systems} and for the given options. Additional kernel
25155 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
25156 loaded at boot time in the order in which they appear.
25159 Needless to say, the initrds we produce and use embed a
25160 statically-linked Guile, and the initialization program is a Guile
25161 program. That gives a lot of flexibility. The
25162 @code{expression->initrd} procedure builds such an initrd, given the
25163 program to run in that initrd.
25165 @deffn {Scheme Procedure} expression->initrd @var{exp} @
25166 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
25167 Return as a file-like object a Linux initrd (a gzipped cpio archive)
25168 containing @var{guile} and that evaluates @var{exp}, a G-expression,
25169 upon booting. All the derivations referenced by @var{exp} are
25170 automatically copied to the initrd.
25173 @node Bootloader Configuration
25174 @section Bootloader Configuration
25177 @cindex boot loader
25179 The operating system supports multiple bootloaders. The bootloader is
25180 configured using @code{bootloader-configuration} declaration. All the
25181 fields of this structure are bootloader agnostic except for one field,
25182 @code{bootloader} that indicates the bootloader to be configured and
25185 Some of the bootloaders do not honor every field of
25186 @code{bootloader-configuration}. For instance, the extlinux
25187 bootloader does not support themes and thus ignores the @code{theme}
25190 @deftp {Data Type} bootloader-configuration
25191 The type of a bootloader configuration declaration.
25195 @item @code{bootloader}
25196 @cindex EFI, bootloader
25197 @cindex UEFI, bootloader
25198 @cindex BIOS, bootloader
25199 The bootloader to use, as a @code{bootloader} object. For now
25200 @code{grub-bootloader}, @code{grub-efi-bootloader},
25201 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
25203 @vindex grub-efi-bootloader
25204 @code{grub-efi-bootloader} allows to boot on modern systems using the
25205 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
25206 use if the installation image contains a @file{/sys/firmware/efi} directory
25207 when you boot it on your system.
25209 @vindex grub-bootloader
25210 @code{grub-bootloader} allows you to boot in particular Intel-based machines
25211 in ``legacy'' BIOS mode.
25213 @cindex ARM, bootloaders
25214 @cindex AArch64, bootloaders
25215 Available bootloaders are described in @code{(gnu bootloader @dots{})}
25216 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
25217 of bootloaders for a wide range of ARM and AArch64 systems, using the
25218 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
25220 @item @code{target}
25221 This is a string denoting the target onto which to install the
25224 The interpretation depends on the bootloader in question. For
25225 @code{grub-bootloader}, for example, it should be a device name understood by
25226 the bootloader @command{installer} command, such as @code{/dev/sda} or
25227 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
25228 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
25229 system, usually @file{/boot/efi}.
25231 @item @code{menu-entries} (default: @code{()})
25232 A possibly empty list of @code{menu-entry} objects (see below), denoting
25233 entries to appear in the bootloader menu, in addition to the current
25234 system entry and the entry pointing to previous system generations.
25236 @item @code{default-entry} (default: @code{0})
25237 The index of the default boot menu entry. Index 0 is for the entry of the
25240 @item @code{timeout} (default: @code{5})
25241 The number of seconds to wait for keyboard input before booting. Set to
25242 0 to boot immediately, and to -1 to wait indefinitely.
25244 @cindex keyboard layout, for the bootloader
25245 @item @code{keyboard-layout} (default: @code{#f})
25246 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
25247 layout, usually US@tie{}English (``qwerty'').
25249 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
25253 This option is currently ignored by bootloaders other than @code{grub} and
25257 @item @code{theme} (default: @var{#f})
25258 The bootloader theme object describing the theme to use. If no theme
25259 is provided, some bootloaders might use a default theme, that's true
25262 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
25263 The output terminals used for the bootloader boot menu, as a list of
25264 symbols. GRUB accepts the values: @code{console}, @code{serial},
25265 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
25266 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
25267 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
25268 configuration,,, grub,GNU GRUB manual}).
25270 @item @code{terminal-inputs} (default: @code{'()})
25271 The input terminals used for the bootloader boot menu, as a list of
25272 symbols. For GRUB, the default is the native platform terminal as
25273 determined at run-time. GRUB accepts the values: @code{console},
25274 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
25275 @code{usb_keyboard}. This field corresponds to the GRUB variable
25276 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
25279 @item @code{serial-unit} (default: @code{#f})
25280 The serial unit used by the bootloader, as an integer from 0 to 3.
25281 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
25282 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
25284 @item @code{serial-speed} (default: @code{#f})
25285 The speed of the serial interface, as an integer. For GRUB, the
25286 default value is chosen at run-time; currently GRUB chooses
25287 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
25294 Should you want to list additional boot menu entries @i{via} the
25295 @code{menu-entries} field above, you will need to create them with the
25296 @code{menu-entry} form. For example, imagine you want to be able to
25297 boot another distro (hard to imagine!), you can define a menu entry
25302 (label "The Other Distro")
25303 (linux "/boot/old/vmlinux-2.6.32")
25304 (linux-arguments '("root=/dev/sda2"))
25305 (initrd "/boot/old/initrd"))
25310 @deftp {Data Type} menu-entry
25311 The type of an entry in the bootloader menu.
25316 The label to show in the menu---e.g., @code{"GNU"}.
25319 The Linux kernel image to boot, for example:
25322 (file-append linux-libre "/bzImage")
25325 For GRUB, it is also possible to specify a device explicitly in the
25326 file path using GRUB's device naming convention (@pxref{Naming
25327 convention,,, grub, GNU GRUB manual}), for example:
25330 "(hd0,msdos1)/boot/vmlinuz"
25333 If the device is specified explicitly as above, then the @code{device}
25334 field is ignored entirely.
25336 @item @code{linux-arguments} (default: @code{()})
25337 The list of extra Linux kernel command-line arguments---e.g.,
25338 @code{("console=ttyS0")}.
25340 @item @code{initrd}
25341 A G-Expression or string denoting the file name of the initial RAM disk
25342 to use (@pxref{G-Expressions}).
25343 @item @code{device} (default: @code{#f})
25344 The device where the kernel and initrd are to be found---i.e., for GRUB,
25345 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
25347 This may be a file system label (a string), a file system UUID (a
25348 bytevector, @pxref{File Systems}), or @code{#f}, in which case
25349 the bootloader will search the device containing the file specified by
25350 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
25351 must @emph{not} be an OS device name such as @file{/dev/sda1}.
25356 @c FIXME: Write documentation once it's stable.
25357 For now only GRUB has theme support. GRUB themes are created using
25358 the @code{grub-theme} form, which is not documented yet.
25360 @defvr {Scheme Variable} %default-theme
25361 This is the default GRUB theme used by the operating system if no
25362 @code{theme} field is specified in @code{bootloader-configuration}
25365 It comes with a fancy background image displaying the GNU and Guix
25370 @node Invoking guix system
25371 @section Invoking @code{guix system}
25373 Once you have written an operating system declaration as seen in the
25374 previous section, it can be @dfn{instantiated} using the @command{guix
25375 system} command. The synopsis is:
25378 guix system @var{options}@dots{} @var{action} @var{file}
25381 @var{file} must be the name of a file containing an
25382 @code{operating-system} declaration. @var{action} specifies how the
25383 operating system is instantiated. Currently the following values are
25388 Display available service type definitions that match the given regular
25389 expressions, sorted by relevance:
25392 $ guix system search console font
25393 name: console-fonts
25394 location: gnu/services/base.scm:729:2
25395 extends: shepherd-root
25396 description: Install the given fonts on the specified ttys (fonts are
25397 + per virtual console on GNU/Linux). The value of this service is a list
25398 + of tty/font pairs like:
25400 + '(("tty1" . "LatGrkCyr-8x16"))
25404 location: gnu/services/base.scm:1048:2
25405 extends: shepherd-root
25406 description: Provide console login using the `mingetty' program.
25410 location: gnu/services/base.scm:775:2
25412 description: Provide a console log-in service as specified by its
25413 + configuration value, a `login-configuration' object.
25419 As for @command{guix package --search}, the result is written in
25420 @code{recutils} format, which makes it easy to filter the output
25421 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
25424 Build the operating system described in @var{file}, activate it, and
25425 switch to it@footnote{This action (and the related actions
25426 @code{switch-generation} and @code{roll-back}) are usable only on
25427 systems already running Guix System.}.
25429 This effects all the configuration specified in @var{file}: user
25430 accounts, system services, global package list, setuid programs, etc.
25431 The command starts system services specified in @var{file} that are not
25432 currently running; if a service is currently running this command will
25433 arrange for it to be upgraded the next time it is stopped (e.g.@: by
25434 @code{herd stop X} or @code{herd restart X}).
25436 This command creates a new generation whose number is one greater than
25437 the current generation (as reported by @command{guix system
25438 list-generations}). If that generation already exists, it will be
25439 overwritten. This behavior mirrors that of @command{guix package}
25440 (@pxref{Invoking guix package}).
25442 It also adds a bootloader menu entry for the new OS configuration,
25443 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
25444 entries for older configurations to a submenu, allowing you to choose
25445 an older system generation at boot time should you need it.
25448 @c The paragraph below refers to the problem discussed at
25449 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
25450 It is highly recommended to run @command{guix pull} once before you run
25451 @command{guix system reconfigure} for the first time (@pxref{Invoking
25452 guix pull}). Failing to do that you would see an older version of Guix
25453 once @command{reconfigure} has completed.
25456 @item switch-generation
25457 @cindex generations
25458 Switch to an existing system generation. This action atomically
25459 switches the system profile to the specified system generation. It
25460 also rearranges the system's existing bootloader menu entries. It
25461 makes the menu entry for the specified system generation the default,
25462 and it moves the entries for the other generatiors to a submenu, if
25463 supported by the bootloader being used. The next time the system
25464 boots, it will use the specified system generation.
25466 The bootloader itself is not being reinstalled when using this
25467 command. Thus, the installed bootloader is used with an updated
25468 configuration file.
25470 The target generation can be specified explicitly by its generation
25471 number. For example, the following invocation would switch to system
25475 guix system switch-generation 7
25478 The target generation can also be specified relative to the current
25479 generation with the form @code{+N} or @code{-N}, where @code{+3} means
25480 ``3 generations ahead of the current generation,'' and @code{-1} means
25481 ``1 generation prior to the current generation.'' When specifying a
25482 negative value such as @code{-1}, you must precede it with @code{--} to
25483 prevent it from being parsed as an option. For example:
25486 guix system switch-generation -- -1
25489 Currently, the effect of invoking this action is @emph{only} to switch
25490 the system profile to an existing generation and rearrange the
25491 bootloader menu entries. To actually start using the target system
25492 generation, you must reboot after running this action. In the future,
25493 it will be updated to do the same things as @command{reconfigure},
25494 like activating and deactivating services.
25496 This action will fail if the specified generation does not exist.
25499 @cindex rolling back
25500 Switch to the preceding system generation. The next time the system
25501 boots, it will use the preceding system generation. This is the inverse
25502 of @command{reconfigure}, and it is exactly the same as invoking
25503 @command{switch-generation} with an argument of @code{-1}.
25505 Currently, as with @command{switch-generation}, you must reboot after
25506 running this action to actually start using the preceding system
25509 @item delete-generations
25510 @cindex deleting system generations
25511 @cindex saving space
25512 Delete system generations, making them candidates for garbage collection
25513 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
25516 This works in the same way as @command{guix package --delete-generations}
25517 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
25518 arguments, all system generations but the current one are deleted:
25521 guix system delete-generations
25524 You can also select the generations you want to delete. The example below
25525 deletes all the system generations that are more than two month old:
25528 guix system delete-generations 2m
25531 Running this command automatically reinstalls the bootloader with an updated
25532 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
25533 longer lists the generations that have been deleted.
25536 Build the derivation of the operating system, which includes all the
25537 configuration files and programs needed to boot and run the system.
25538 This action does not actually install anything.
25541 Populate the given directory with all the files necessary to run the
25542 operating system specified in @var{file}. This is useful for first-time
25543 installations of Guix System. For instance:
25546 guix system init my-os-config.scm /mnt
25549 copies to @file{/mnt} all the store items required by the configuration
25550 specified in @file{my-os-config.scm}. This includes configuration
25551 files, packages, and so on. It also creates other essential files
25552 needed for the system to operate correctly---e.g., the @file{/etc},
25553 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
25555 This command also installs bootloader on the target specified in
25556 @file{my-os-config}, unless the @option{--no-bootloader} option was
25560 @cindex virtual machine
25562 @anchor{guix system vm}
25563 Build a virtual machine that contains the operating system declared in
25564 @var{file}, and return a script to run that virtual machine (VM).
25567 The @code{vm} action and others below
25568 can use KVM support in the Linux-libre kernel. Specifically, if the
25569 machine has hardware virtualization support, the corresponding
25570 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
25571 must exist and be readable and writable by the user and by the
25572 build users of the daemon (@pxref{Build Environment Setup}).
25575 Arguments given to the script are passed to QEMU as in the example
25576 below, which enables networking and requests 1@tie{}GiB of RAM for the
25580 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -net user
25583 The VM shares its store with the host system.
25585 Additional file systems can be shared between the host and the VM using
25586 the @code{--share} and @code{--expose} command-line options: the former
25587 specifies a directory to be shared with write access, while the latter
25588 provides read-only access to the shared directory.
25590 The example below creates a VM in which the user's home directory is
25591 accessible read-only, and where the @file{/exchange} directory is a
25592 read-write mapping of @file{$HOME/tmp} on the host:
25595 guix system vm my-config.scm \
25596 --expose=$HOME --share=$HOME/tmp=/exchange
25599 On GNU/Linux, the default is to boot directly to the kernel; this has
25600 the advantage of requiring only a very tiny root disk image since the
25601 store of the host can then be mounted.
25603 The @code{--full-boot} option forces a complete boot sequence, starting
25604 with the bootloader. This requires more disk space since a root image
25605 containing at least the kernel, initrd, and bootloader data files must
25606 be created. The @code{--image-size} option can be used to specify the
25609 @cindex System images, creation in various formats
25610 @cindex Creating system images in various formats
25613 @itemx docker-image
25614 Return a virtual machine, disk image, or Docker image of the operating
25615 system declared in @var{file} that stands alone. By default,
25616 @command{guix system} estimates the size of the image needed to store
25617 the system, but you can use the @option{--image-size} option to specify
25618 a value. Docker images are built to contain exactly what they need, so
25619 the @option{--image-size} option is ignored in the case of
25620 @code{docker-image}.
25622 You can specify the root file system type by using the
25623 @option{--file-system-type} option. It defaults to @code{ext4}.
25625 When using @code{vm-image}, the returned image is in qcow2 format, which
25626 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
25627 for more information on how to run the image in a virtual machine.
25629 When using @code{disk-image}, a raw disk image is produced; it can be
25630 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
25631 the device corresponding to a USB stick, one can copy the image to it
25632 using the following command:
25635 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
25638 When using @code{docker-image}, a Docker image is produced. Guix builds
25639 the image from scratch, not from a pre-existing Docker base image. As a
25640 result, it contains @emph{exactly} what you define in the operating
25641 system configuration file. You can then load the image and launch a
25642 Docker container using commands like the following:
25645 image_id="`docker load < guix-system-docker-image.tar.gz`"
25646 container_id="`docker create $image_id`"
25647 docker start $container_id
25650 This command starts a new Docker container from the specified image. It
25651 will boot the Guix system in the usual manner, which means it will
25652 start any services you have defined in the operating system
25653 configuration. You can get an interactive shell running in the container
25654 using @command{docker exec}:
25657 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
25660 Depending on what you run in the Docker container, it
25661 may be necessary to give the container additional permissions. For
25662 example, if you intend to build software using Guix inside of the Docker
25663 container, you may need to pass the @option{--privileged} option to
25664 @code{docker create}.
25667 Return a script to run the operating system declared in @var{file}
25668 within a container. Containers are a set of lightweight isolation
25669 mechanisms provided by the kernel Linux-libre. Containers are
25670 substantially less resource-demanding than full virtual machines since
25671 the kernel, shared objects, and other resources can be shared with the
25672 host system; this also means they provide thinner isolation.
25674 Currently, the script must be run as root in order to support more than
25675 a single user and group. The container shares its store with the host
25678 As with the @code{vm} action (@pxref{guix system vm}), additional file
25679 systems to be shared between the host and container can be specified
25680 using the @option{--share} and @option{--expose} options:
25683 guix system container my-config.scm \
25684 --expose=$HOME --share=$HOME/tmp=/exchange
25688 This option requires Linux-libre 3.19 or newer.
25693 @var{options} can contain any of the common build options (@pxref{Common
25694 Build Options}). In addition, @var{options} can contain one of the
25698 @item --expression=@var{expr}
25699 @itemx -e @var{expr}
25700 Consider the operating-system @var{expr} evaluates to.
25701 This is an alternative to specifying a file which evaluates to an
25703 This is used to generate the Guix system installer @pxref{Building the
25704 Installation Image}).
25706 @item --system=@var{system}
25707 @itemx -s @var{system}
25708 Attempt to build for @var{system} instead of the host system type.
25709 This works as per @command{guix build} (@pxref{Invoking guix build}).
25713 Return the derivation file name of the given operating system without
25716 @item --file-system-type=@var{type}
25717 @itemx -t @var{type}
25718 For the @code{disk-image} action, create a file system of the given
25719 @var{type} on the image.
25721 When this option is omitted, @command{guix system} uses @code{ext4}.
25723 @cindex ISO-9660 format
25724 @cindex CD image format
25725 @cindex DVD image format
25726 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
25727 for burning on CDs and DVDs.
25729 @item --image-size=@var{size}
25730 For the @code{vm-image} and @code{disk-image} actions, create an image
25731 of the given @var{size}. @var{size} may be a number of bytes, or it may
25732 include a unit as a suffix (@pxref{Block size, size specifications,,
25733 coreutils, GNU Coreutils}).
25735 When this option is omitted, @command{guix system} computes an estimate
25736 of the image size as a function of the size of the system declared in
25741 For the @code{container} action, allow containers to access the host network,
25742 that is, do not create a network namespace.
25744 @item --root=@var{file}
25745 @itemx -r @var{file}
25746 Make @var{file} a symlink to the result, and register it as a garbage
25749 @item --skip-checks
25750 Skip pre-installation safety checks.
25752 By default, @command{guix system init} and @command{guix system
25753 reconfigure} perform safety checks: they make sure the file systems that
25754 appear in the @code{operating-system} declaration actually exist
25755 (@pxref{File Systems}), and that any Linux kernel modules that may be
25756 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
25757 RAM Disk}). Passing this option skips these tests altogether.
25760 @cindex on-error strategy
25761 @cindex error strategy
25762 @item --on-error=@var{strategy}
25763 Apply @var{strategy} when an error occurs when reading @var{file}.
25764 @var{strategy} may be one of the following:
25767 @item nothing-special
25768 Report the error concisely and exit. This is the default strategy.
25771 Likewise, but also display a backtrace.
25774 Report the error and enter Guile's debugger. From there, you can run
25775 commands such as @code{,bt} to get a backtrace, @code{,locals} to
25776 display local variable values, and more generally inspect the state of the
25777 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
25778 a list of available debugging commands.
25782 Once you have built, configured, re-configured, and re-re-configured
25783 your Guix installation, you may find it useful to list the operating
25784 system generations available on disk---and that you can choose from the
25785 bootloader boot menu:
25789 @item list-generations
25790 List a summary of each generation of the operating system available on
25791 disk, in a human-readable way. This is similar to the
25792 @option{--list-generations} option of @command{guix package}
25793 (@pxref{Invoking guix package}).
25795 Optionally, one can specify a pattern, with the same syntax that is used
25796 in @command{guix package --list-generations}, to restrict the list of
25797 generations displayed. For instance, the following command displays
25798 generations that are up to 10 days old:
25801 $ guix system list-generations 10d
25806 The @command{guix system} command has even more to offer! The following
25807 sub-commands allow you to visualize how your system services relate to
25810 @anchor{system-extension-graph}
25813 @item extension-graph
25814 Emit in Dot/Graphviz format to standard output the @dfn{service
25815 extension graph} of the operating system defined in @var{file}
25816 (@pxref{Service Composition}, for more information on service
25822 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
25825 produces a PDF file showing the extension relations among services.
25827 @anchor{system-shepherd-graph}
25828 @item shepherd-graph
25829 Emit in Dot/Graphviz format to standard output the @dfn{dependency
25830 graph} of shepherd services of the operating system defined in
25831 @var{file}. @xref{Shepherd Services}, for more information and for an
25836 @node Invoking guix deploy
25837 @section Invoking @code{guix deploy}
25839 We've already seen @code{operating-system} declarations used to manage a
25840 machine's configuration locally. Suppose you need to configure multiple
25841 machines, though---perhaps you're managing a service on the web that's
25842 comprised of several servers. @command{guix deploy} enables you to use those
25843 same @code{operating-system} declarations to manage multiple remote hosts at
25844 once as a logical ``deployment''.
25847 The functionality described in this section is still under development
25848 and is subject to change. Get in touch with us on
25849 @email{guix-devel@@gnu.org}!
25853 guix deploy @var{file}
25856 Such an invocation will deploy the machines that the code within @var{file}
25857 evaluates to. As an example, @var{file} might contain a definition like this:
25860 ;; This is a Guix deployment of a "bare bones" setup, with
25861 ;; no X11 display server, to a machine with an SSH daemon
25862 ;; listening on localhost:2222. A configuration such as this
25863 ;; may be appropriate for virtual machine with ports
25864 ;; forwarded to the host's loopback interface.
25866 (use-service-modules networking ssh)
25867 (use-package-modules bootloaders)
25871 (host-name "gnu-deployed")
25872 (timezone "Etc/UTC")
25873 (bootloader (bootloader-configuration
25874 (bootloader grub-bootloader)
25875 (target "/dev/vda")
25876 (terminal-outputs '(console))))
25877 (file-systems (cons (file-system
25879 (device "/dev/vda1")
25881 %base-file-systems))
25883 (append (list (service dhcp-client-service-type)
25884 (service openssh-service-type
25885 (openssh-configuration
25886 (permit-root-login #t)
25887 (allow-empty-passwords? #t))))
25891 (operating-system %system)
25892 (environment managed-host-environment-type)
25893 (configuration (machine-ssh-configuration
25894 (host-name "localhost")
25895 (system "x86_64-linux")
25897 (identity "./id_rsa")
25901 The file should evaluate to a list of @var{machine} objects. This example,
25902 upon being deployed, will create a new generation on the remote system
25903 realizing the @code{operating-system} declaration @var{%system}.
25904 @var{environment} and @var{configuration} specify how the machine should be
25905 provisioned---that is, how the computing resources should be created and
25906 managed. The above example does not create any resources, as a
25907 @code{'managed-host} is a machine that is already running the Guix system and
25908 available over the network. This is a particularly simple case; a more
25909 complex deployment may involve, for example, starting virtual machines through
25910 a Virtual Private Server (VPS) provider. In such a case, a different
25911 @var{environment} type would be used.
25913 Do note that you first need to generate a key pair on the coordinator machine
25914 to allow the daemon to export signed archives of files from the store
25915 (@pxref{Invoking guix archive}).
25918 # guix archive --generate-key
25922 Each target machine must authorize the key of the master machine so that it
25923 accepts store items it receives from the coordinator:
25926 # guix archive --authorize < coordinator-public-key.txt
25929 @code{user}, in this example, specifies the name of the user account to log in
25930 as to perform the deployment. Its default value is @code{root}, but root
25931 login over SSH may be forbidden in some cases. To work around this,
25932 @command{guix deploy} can log in as an unprivileged user and employ
25933 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
25934 currently installed on the remote and can be invoked non-interactively as
25935 @code{user}. That is: the line in @code{sudoers} granting @code{user} the
25936 ability to use @code{sudo} must contain the @code{NOPASSWD} tag.
25938 @deftp {Data Type} machine
25939 This is the data type representing a single machine in a heterogeneous Guix
25943 @item @code{operating-system}
25944 The object of the operating system configuration to deploy.
25946 @item @code{environment}
25947 An @code{environment-type} describing how the machine should be provisioned.
25948 At the moment, the only supported value is
25949 @code{managed-host-environment-type}.
25951 @item @code{configuration} (default: @code{#f})
25952 An object describing the configuration for the machine's @code{environment}.
25953 If the @code{environment} has a default configuration, @code{#f} maybe used.
25954 If @code{#f} is used for an environment with no default configuration,
25955 however, an error will be thrown.
25959 @deftp {Data Type} machine-ssh-configuration
25960 This is the data type representing the SSH client parameters for a machine
25961 with an @code{environment} of @code{managed-host-environment-type}.
25964 @item @code{host-name}
25965 @item @code{build-locally?} (default: @code{#t})
25966 If false, system derivations will be built on the machine being deployed to.
25967 @item @code{system}
25968 The Nix system type describing the architecture of the machine being deployed
25969 to. This should look something like ``x86_64-linux''.
25970 @item @code{authorize?} (default: @code{#t})
25971 If true, the coordinator's signing key will be added to the remote's ACL
25973 @item @code{port} (default: @code{22})
25974 @item @code{user} (default: @code{"root"})
25975 @item @code{identity} (default: @code{#f})
25976 If specified, the path to the SSH private key to use to authenticate with the
25981 @node Running Guix in a VM
25982 @section Running Guix in a Virtual Machine
25984 @cindex virtual machine
25985 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
25987 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
25988 This image is a compressed image in QCOW format. You will first need to
25989 decompress with @command{xz -d}, and then you can pass it to an emulator such
25990 as QEMU (see below for details).
25992 This image boots the Xfce graphical environment and it contains some
25993 commonly-used tools. You can install more software in the image by running
25994 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
25995 also reconfigure the system based on its initial configuration file available
25996 as @file{/etc/config.scm} (@pxref{Using the Configuration System}).
25998 Instead of using this pre-built image, one can also build their own virtual
25999 machine image using @command{guix system vm-image} (@pxref{Invoking guix
26000 system}). The returned image is in qcow2 format, which the
26001 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
26004 If you built your own image, you must copy it out of the store
26005 (@pxref{The Store}) and give yourself permission to write to the copy
26006 before you can use it. When invoking QEMU, you must choose a system
26007 emulator that is suitable for your hardware platform. Here is a minimal
26008 QEMU invocation that will boot the result of @command{guix system
26009 vm-image} on x86_64 hardware:
26012 $ qemu-system-x86_64 \
26013 -net user -net nic,model=virtio \
26014 -enable-kvm -m 1024 \
26015 -device virtio-blk,drive=myhd \
26016 -drive if=none,file=/tmp/qemu-image,id=myhd
26019 Here is what each of these options means:
26022 @item qemu-system-x86_64
26023 This specifies the hardware platform to emulate. This should match the
26027 Enable the unprivileged user-mode network stack. The guest OS can
26028 access the host but not vice versa. This is the simplest way to get the
26031 @item -net nic,model=virtio
26032 You must create a network interface of a given model. If you do not
26033 create a NIC, the boot will fail. Assuming your hardware platform is
26034 x86_64, you can get a list of available NIC models by running
26035 @command{qemu-system-x86_64 -net nic,model=help}.
26038 If your system has hardware virtualization extensions, enabling the
26039 virtual machine support (KVM) of the Linux kernel will make things run
26042 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
26044 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
26045 which may be insufficient for some operations.
26047 @item -device virtio-blk,drive=myhd
26048 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
26049 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
26050 better performance than if it were emulating a complete disk drive. See the
26051 QEMU and KVM documentation for more info.
26053 @item -drive if=none,file=/tmp/qemu-image,id=myhd
26054 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
26055 the ``myhd'' drive.
26058 The default @command{run-vm.sh} script that is returned by an invocation of
26059 @command{guix system vm} does not add a @command{-net user} flag by default.
26060 To get network access from within the vm add the @code{(dhcp-client-service)}
26061 to your system definition and start the VM using
26062 @command{`guix system vm config.scm` -net user}. An important caveat of using
26063 @command{-net user} for networking is that @command{ping} will not work, because
26064 it uses the ICMP protocol. You'll have to use a different command to check for
26065 network connectivity, for example @command{guix download}.
26067 @subsection Connecting Through SSH
26071 To enable SSH inside a VM you need to add an SSH server like
26072 @code{openssh-service-type} to your VM (@pxref{Networking Services,
26073 @code{openssh-service-type}}). In addition you need to forward the SSH port,
26074 22 by default, to the host. You can do this with
26077 `guix system vm config.scm` -net user,hostfwd=tcp::10022-:22
26080 To connect to the VM you can run
26083 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
26086 The @command{-p} tells @command{ssh} the port you want to connect to.
26087 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
26088 every time you modify your @command{config.scm} file and the
26089 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
26090 connection to an unknown host every time you connect.
26092 @subsection Using @command{virt-viewer} with Spice
26094 As an alternative to the default @command{qemu} graphical client you can
26095 use the @command{remote-viewer} from the @command{virt-viewer} package. To
26096 connect pass the @command{-spice port=5930,disable-ticketing} flag to
26097 @command{qemu}. See previous section for further information on how to do this.
26099 Spice also allows you to do some nice stuff like share your clipboard with your
26100 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
26103 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
26104 -chardev spicevmc,name=vdagent,id=vdagent
26105 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
26106 name=com.redhat.spice.0
26109 You'll also need to add the @pxref{Miscellaneous Services, Spice service}.
26111 @node Defining Services
26112 @section Defining Services
26114 The previous sections show the available services and how one can combine
26115 them in an @code{operating-system} declaration. But how do we define
26116 them in the first place? And what is a service anyway?
26119 * Service Composition:: The model for composing services.
26120 * Service Types and Services:: Types and services.
26121 * Service Reference:: API reference.
26122 * Shepherd Services:: A particular type of service.
26125 @node Service Composition
26126 @subsection Service Composition
26130 Here we define a @dfn{service} as, broadly, something that extends the
26131 functionality of the operating system. Often a service is a process---a
26132 @dfn{daemon}---started when the system boots: a secure shell server, a
26133 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
26134 whose execution can be triggered by another daemon---e.g., an FTP server
26135 started by @command{inetd} or a D-Bus service activated by
26136 @command{dbus-daemon}. Occasionally, a service does not map to a
26137 daemon. For instance, the ``account'' service collects user accounts
26138 and makes sure they exist when the system runs; the ``udev'' service
26139 collects device management rules and makes them available to the eudev
26140 daemon; the @file{/etc} service populates the @file{/etc} directory
26143 @cindex service extensions
26144 Guix system services are connected by @dfn{extensions}. For instance, the
26145 secure shell service @emph{extends} the Shepherd---the
26146 initialization system, running as PID@tie{}1---by giving it the command
26147 lines to start and stop the secure shell daemon (@pxref{Networking
26148 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
26149 service by passing it its @file{.service} specification, and extends the
26150 udev service by passing it device management rules (@pxref{Desktop
26151 Services, @code{upower-service}}); the Guix daemon service extends the
26152 Shepherd by passing it the command lines to start and stop the daemon,
26153 and extends the account service by passing it a list of required build
26154 user accounts (@pxref{Base Services}).
26156 All in all, services and their ``extends'' relations form a directed
26157 acyclic graph (DAG). If we represent services as boxes and extensions
26158 as arrows, a typical system might provide something like this:
26160 @image{images/service-graph,,5in,Typical service extension graph.}
26162 @cindex system service
26163 At the bottom, we see the @dfn{system service}, which produces the
26164 directory containing everything to run and boot the system, as returned
26165 by the @command{guix system build} command. @xref{Service Reference},
26166 to learn about the other service types shown here.
26167 @xref{system-extension-graph, the @command{guix system extension-graph}
26168 command}, for information on how to generate this representation for a
26169 particular operating system definition.
26171 @cindex service types
26172 Technically, developers can define @dfn{service types} to express these
26173 relations. There can be any number of services of a given type on the
26174 system---for instance, a system running two instances of the GNU secure
26175 shell server (lsh) has two instances of @code{lsh-service-type}, with
26176 different parameters.
26178 The following section describes the programming interface for service
26179 types and services.
26181 @node Service Types and Services
26182 @subsection Service Types and Services
26184 A @dfn{service type} is a node in the DAG described above. Let us start
26185 with a simple example, the service type for the Guix build daemon
26186 (@pxref{Invoking guix-daemon}):
26189 (define guix-service-type
26193 (list (service-extension shepherd-root-service-type guix-shepherd-service)
26194 (service-extension account-service-type guix-accounts)
26195 (service-extension activation-service-type guix-activation)))
26196 (default-value (guix-configuration))))
26200 It defines three things:
26204 A name, whose sole purpose is to make inspection and debugging easier.
26207 A list of @dfn{service extensions}, where each extension designates the
26208 target service type and a procedure that, given the parameters of the
26209 service, returns a list of objects to extend the service of that type.
26211 Every service type has at least one service extension. The only
26212 exception is the @dfn{boot service type}, which is the ultimate service.
26215 Optionally, a default value for instances of this type.
26218 In this example, @code{guix-service-type} extends three services:
26221 @item shepherd-root-service-type
26222 The @code{guix-shepherd-service} procedure defines how the Shepherd
26223 service is extended. Namely, it returns a @code{<shepherd-service>}
26224 object that defines how @command{guix-daemon} is started and stopped
26225 (@pxref{Shepherd Services}).
26227 @item account-service-type
26228 This extension for this service is computed by @code{guix-accounts},
26229 which returns a list of @code{user-group} and @code{user-account}
26230 objects representing the build user accounts (@pxref{Invoking
26233 @item activation-service-type
26234 Here @code{guix-activation} is a procedure that returns a gexp, which is
26235 a code snippet to run at ``activation time''---e.g., when the service is
26239 A service of this type is instantiated like this:
26242 (service guix-service-type
26243 (guix-configuration
26245 (use-substitutes? #f)))
26248 The second argument to the @code{service} form is a value representing
26249 the parameters of this specific service instance.
26250 @xref{guix-configuration-type, @code{guix-configuration}}, for
26251 information about the @code{guix-configuration} data type. When the
26252 value is omitted, the default value specified by
26253 @code{guix-service-type} is used:
26256 (service guix-service-type)
26259 @code{guix-service-type} is quite simple because it extends other
26260 services but is not extensible itself.
26262 @c @subsubsubsection Extensible Service Types
26264 The service type for an @emph{extensible} service looks like this:
26267 (define udev-service-type
26268 (service-type (name 'udev)
26270 (list (service-extension shepherd-root-service-type
26271 udev-shepherd-service)))
26273 (compose concatenate) ;concatenate the list of rules
26274 (extend (lambda (config rules)
26276 (($ <udev-configuration> udev initial-rules)
26277 (udev-configuration
26278 (udev udev) ;the udev package to use
26279 (rules (append initial-rules rules)))))))))
26282 This is the service type for the
26283 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
26284 management daemon}. Compared to the previous example, in addition to an
26285 extension of @code{shepherd-root-service-type}, we see two new fields:
26289 This is the procedure to @dfn{compose} the list of extensions to
26290 services of this type.
26292 Services can extend the udev service by passing it lists of rules; we
26293 compose those extensions simply by concatenating them.
26296 This procedure defines how the value of the service is @dfn{extended} with
26297 the composition of the extensions.
26299 Udev extensions are composed into a list of rules, but the udev service
26300 value is itself a @code{<udev-configuration>} record. So here, we
26301 extend that record by appending the list of rules it contains to the
26302 list of contributed rules.
26305 This is a string giving an overview of the service type. The string can
26306 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
26307 @command{guix system search} command searches these strings and displays
26308 them (@pxref{Invoking guix system}).
26311 There can be only one instance of an extensible service type such as
26312 @code{udev-service-type}. If there were more, the
26313 @code{service-extension} specifications would be ambiguous.
26315 Still here? The next section provides a reference of the programming
26316 interface for services.
26318 @node Service Reference
26319 @subsection Service Reference
26321 We have seen an overview of service types (@pxref{Service Types and
26322 Services}). This section provides a reference on how to manipulate
26323 services and service types. This interface is provided by the
26324 @code{(gnu services)} module.
26326 @deffn {Scheme Procedure} service @var{type} [@var{value}]
26327 Return a new service of @var{type}, a @code{<service-type>} object (see
26328 below.) @var{value} can be any object; it represents the parameters of
26329 this particular service instance.
26331 When @var{value} is omitted, the default value specified by @var{type}
26332 is used; if @var{type} does not specify a default value, an error is
26335 For instance, this:
26338 (service openssh-service-type)
26342 is equivalent to this:
26345 (service openssh-service-type
26346 (openssh-configuration))
26349 In both cases the result is an instance of @code{openssh-service-type}
26350 with the default configuration.
26353 @deffn {Scheme Procedure} service? @var{obj}
26354 Return true if @var{obj} is a service.
26357 @deffn {Scheme Procedure} service-kind @var{service}
26358 Return the type of @var{service}---i.e., a @code{<service-type>} object.
26361 @deffn {Scheme Procedure} service-value @var{service}
26362 Return the value associated with @var{service}. It represents its
26366 Here is an example of how a service is created and manipulated:
26370 (service nginx-service-type
26371 (nginx-configuration
26373 (log-directory log-directory)
26374 (run-directory run-directory)
26375 (file config-file))))
26380 (eq? (service-kind s) nginx-service-type)
26384 The @code{modify-services} form provides a handy way to change the
26385 parameters of some of the services of a list such as
26386 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
26387 evaluates to a list of services. Of course, you could always use
26388 standard list combinators such as @code{map} and @code{fold} to do that
26389 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
26390 @code{modify-services} simply provides a more concise form for this
26393 @deffn {Scheme Syntax} modify-services @var{services} @
26394 (@var{type} @var{variable} => @var{body}) @dots{}
26396 Modify the services listed in @var{services} according to the given
26397 clauses. Each clause has the form:
26400 (@var{type} @var{variable} => @var{body})
26403 where @var{type} is a service type---e.g.,
26404 @code{guix-service-type}---and @var{variable} is an identifier that is
26405 bound within the @var{body} to the service parameters---e.g., a
26406 @code{guix-configuration} instance---of the original service of that
26409 The @var{body} should evaluate to the new service parameters, which will
26410 be used to configure the new service. This new service will replace the
26411 original in the resulting list. Because a service's service parameters
26412 are created using @code{define-record-type*}, you can write a succinct
26413 @var{body} that evaluates to the new service parameters by using the
26414 @code{inherit} feature that @code{define-record-type*} provides.
26416 @xref{Using the Configuration System}, for example usage.
26420 Next comes the programming interface for service types. This is
26421 something you want to know when writing new service definitions, but not
26422 necessarily when simply looking for ways to customize your
26423 @code{operating-system} declaration.
26425 @deftp {Data Type} service-type
26426 @cindex service type
26427 This is the representation of a @dfn{service type} (@pxref{Service Types
26432 This is a symbol, used only to simplify inspection and debugging.
26434 @item @code{extensions}
26435 A non-empty list of @code{<service-extension>} objects (see below).
26437 @item @code{compose} (default: @code{#f})
26438 If this is @code{#f}, then the service type denotes services that cannot
26439 be extended---i.e., services that do not receive ``values'' from other
26442 Otherwise, it must be a one-argument procedure. The procedure is called
26443 by @code{fold-services} and is passed a list of values collected from
26444 extensions. It may return any single value.
26446 @item @code{extend} (default: @code{#f})
26447 If this is @code{#f}, services of this type cannot be extended.
26449 Otherwise, it must be a two-argument procedure: @code{fold-services}
26450 calls it, passing it the initial value of the service as the first
26451 argument and the result of applying @code{compose} to the extension
26452 values as the second argument. It must return a value that is a valid
26453 parameter value for the service instance.
26456 @xref{Service Types and Services}, for examples.
26459 @deffn {Scheme Procedure} service-extension @var{target-type} @
26461 Return a new extension for services of type @var{target-type}.
26462 @var{compute} must be a one-argument procedure: @code{fold-services}
26463 calls it, passing it the value associated with the service that provides
26464 the extension; it must return a valid value for the target service.
26467 @deffn {Scheme Procedure} service-extension? @var{obj}
26468 Return true if @var{obj} is a service extension.
26471 Occasionally, you might want to simply extend an existing service. This
26472 involves creating a new service type and specifying the extension of
26473 interest, which can be verbose; the @code{simple-service} procedure
26474 provides a shorthand for this.
26476 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
26477 Return a service that extends @var{target} with @var{value}. This works
26478 by creating a singleton service type @var{name}, of which the returned
26479 service is an instance.
26481 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
26485 (simple-service 'my-mcron-job mcron-service-type
26486 #~(job '(next-hour (3)) "guix gc -F 2G"))
26490 At the core of the service abstraction lies the @code{fold-services}
26491 procedure, which is responsible for ``compiling'' a list of services
26492 down to a single directory that contains everything needed to boot and
26493 run the system---the directory shown by the @command{guix system build}
26494 command (@pxref{Invoking guix system}). In essence, it propagates
26495 service extensions down the service graph, updating each node parameters
26496 on the way, until it reaches the root node.
26498 @deffn {Scheme Procedure} fold-services @var{services} @
26499 [#:target-type @var{system-service-type}]
26500 Fold @var{services} by propagating their extensions down to the root of
26501 type @var{target-type}; return the root service adjusted accordingly.
26504 Lastly, the @code{(gnu services)} module also defines several essential
26505 service types, some of which are listed below.
26507 @defvr {Scheme Variable} system-service-type
26508 This is the root of the service graph. It produces the system directory
26509 as returned by the @command{guix system build} command.
26512 @defvr {Scheme Variable} boot-service-type
26513 The type of the ``boot service'', which produces the @dfn{boot script}.
26514 The boot script is what the initial RAM disk runs when booting.
26517 @defvr {Scheme Variable} etc-service-type
26518 The type of the @file{/etc} service. This service is used to create
26519 files under @file{/etc} and can be extended by
26520 passing it name/file tuples such as:
26523 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
26526 In this example, the effect would be to add an @file{/etc/issue} file
26527 pointing to the given file.
26530 @defvr {Scheme Variable} setuid-program-service-type
26531 Type for the ``setuid-program service''. This service collects lists of
26532 executable file names, passed as gexps, and adds them to the set of
26533 setuid-root programs on the system (@pxref{Setuid Programs}).
26536 @defvr {Scheme Variable} profile-service-type
26537 Type of the service that populates the @dfn{system profile}---i.e., the
26538 programs under @file{/run/current-system/profile}. Other services can
26539 extend it by passing it lists of packages to add to the system profile.
26543 @node Shepherd Services
26544 @subsection Shepherd Services
26546 @cindex shepherd services
26548 @cindex init system
26549 The @code{(gnu services shepherd)} module provides a way to define
26550 services managed by the GNU@tie{}Shepherd, which is the
26551 initialization system---the first process that is started when the
26552 system boots, also known as PID@tie{}1
26553 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
26555 Services in the Shepherd can depend on each other. For instance, the
26556 SSH daemon may need to be started after the syslog daemon has been
26557 started, which in turn can only happen once all the file systems have
26558 been mounted. The simple operating system defined earlier (@pxref{Using
26559 the Configuration System}) results in a service graph like this:
26561 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
26563 You can actually generate such a graph for any operating system
26564 definition using the @command{guix system shepherd-graph} command
26565 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
26567 The @code{%shepherd-root-service} is a service object representing
26568 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
26569 by passing it lists of @code{<shepherd-service>} objects.
26571 @deftp {Data Type} shepherd-service
26572 The data type representing a service managed by the Shepherd.
26575 @item @code{provision}
26576 This is a list of symbols denoting what the service provides.
26578 These are the names that may be passed to @command{herd start},
26579 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
26580 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
26581 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
26583 @item @code{requirement} (default: @code{'()})
26584 List of symbols denoting the Shepherd services this one depends on.
26586 @cindex one-shot services, for the Shepherd
26587 @item @code{one-shot?} (default: @code{#f})
26588 Whether this service is @dfn{one-shot}. One-shot services stop immediately
26589 after their @code{start} action has completed. @xref{Slots of services,,,
26590 shepherd, The GNU Shepherd Manual}, for more info.
26592 @item @code{respawn?} (default: @code{#t})
26593 Whether to restart the service when it stops, for instance when the
26594 underlying process dies.
26597 @itemx @code{stop} (default: @code{#~(const #f)})
26598 The @code{start} and @code{stop} fields refer to the Shepherd's
26599 facilities to start and stop processes (@pxref{Service De- and
26600 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
26601 G-expressions that get expanded in the Shepherd configuration file
26602 (@pxref{G-Expressions}).
26604 @item @code{actions} (default: @code{'()})
26605 @cindex actions, of Shepherd services
26606 This is a list of @code{shepherd-action} objects (see below) defining
26607 @dfn{actions} supported by the service, in addition to the standard
26608 @code{start} and @code{stop} actions. Actions listed here become available as
26609 @command{herd} sub-commands:
26612 herd @var{action} @var{service} [@var{arguments}@dots{}]
26615 @item @code{auto-start?} (default: @code{#t})
26616 Whether this service should be started automatically by the Shepherd. If it
26617 is @code{#f} the service has to be started manually with @code{herd start}.
26619 @item @code{documentation}
26620 A documentation string, as shown when running:
26623 herd doc @var{service-name}
26626 where @var{service-name} is one of the symbols in @code{provision}
26627 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
26629 @item @code{modules} (default: @code{%default-modules})
26630 This is the list of modules that must be in scope when @code{start} and
26631 @code{stop} are evaluated.
26636 @deftp {Data Type} shepherd-action
26637 This is the data type that defines additional actions implemented by a
26638 Shepherd service (see above).
26642 Symbol naming the action.
26644 @item documentation
26645 This is a documentation string for the action. It can be viewed by running:
26648 herd doc @var{service} action @var{action}
26652 This should be a gexp that evaluates to a procedure of at least one argument,
26653 which is the ``running value'' of the service (@pxref{Slots of services,,,
26654 shepherd, The GNU Shepherd Manual}).
26657 The following example defines an action called @code{say-hello} that kindly
26663 (documentation "Say hi!")
26664 (procedure #~(lambda (running . args)
26665 (format #t "Hello, friend! arguments: ~s\n"
26670 Assuming this action is added to the @code{example} service, then you can do:
26673 # herd say-hello example
26674 Hello, friend! arguments: ()
26675 # herd say-hello example a b c
26676 Hello, friend! arguments: ("a" "b" "c")
26679 This, as you can see, is a fairly sophisticated way to say hello.
26680 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
26684 @defvr {Scheme Variable} shepherd-root-service-type
26685 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
26687 This is the service type that extensions target when they want to create
26688 shepherd services (@pxref{Service Types and Services}, for an example).
26689 Each extension must pass a list of @code{<shepherd-service>}.
26692 @defvr {Scheme Variable} %shepherd-root-service
26693 This service represents PID@tie{}1.
26697 @node Documentation
26698 @chapter Documentation
26700 @cindex documentation, searching for
26701 @cindex searching for documentation
26702 @cindex Info, documentation format
26704 @cindex manual pages
26705 In most cases packages installed with Guix come with documentation.
26706 There are two main documentation formats: ``Info'', a browseable
26707 hypertext format used for GNU software, and ``manual pages'' (or ``man
26708 pages''), the linear documentation format traditionally found on Unix.
26709 Info manuals are accessed with the @command{info} command or with Emacs,
26710 and man pages are accessed using @command{man}.
26712 You can look for documentation of software installed on your system by
26713 keyword. For example, the following command searches for information
26714 about ``TLS'' in Info manuals:
26718 "(emacs)Network Security" -- STARTTLS
26719 "(emacs)Network Security" -- TLS
26720 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
26721 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
26726 The command below searches for the same keyword in man pages:
26730 SSL (7) - OpenSSL SSL/TLS library
26731 certtool (1) - GnuTLS certificate tool
26735 These searches are purely local to your computer so you have the
26736 guarantee that documentation you find corresponds to what you have
26737 actually installed, you can access it off-line, and your privacy is
26740 Once you have these results, you can view the relevant documentation by
26744 $ info "(gnutls)Core TLS API"
26754 Info manuals contain sections and indices as well as hyperlinks like
26755 those found in Web pages. The @command{info} reader (@pxref{Top, Info
26756 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
26757 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
26758 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
26759 Introduction}, for an introduction to Info navigation.
26761 @node Installing Debugging Files
26762 @chapter Installing Debugging Files
26764 @cindex debugging files
26765 Program binaries, as produced by the GCC compilers for instance, are
26766 typically written in the ELF format, with a section containing
26767 @dfn{debugging information}. Debugging information is what allows the
26768 debugger, GDB, to map binary code to source code; it is required to
26769 debug a compiled program in good conditions.
26771 The problem with debugging information is that is takes up a fair amount
26772 of disk space. For example, debugging information for the GNU C Library
26773 weighs in at more than 60 MiB. Thus, as a user, keeping all the
26774 debugging info of all the installed programs is usually not an option.
26775 Yet, space savings should not come at the cost of an impediment to
26776 debugging---especially in the GNU system, which should make it easier
26777 for users to exert their computing freedom (@pxref{GNU Distribution}).
26779 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
26780 mechanism that allows users to get the best of both worlds: debugging
26781 information can be stripped from the binaries and stored in separate
26782 files. GDB is then able to load debugging information from those files,
26783 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
26786 The GNU distribution takes advantage of this by storing debugging
26787 information in the @code{lib/debug} sub-directory of a separate package
26788 output unimaginatively called @code{debug} (@pxref{Packages with
26789 Multiple Outputs}). Users can choose to install the @code{debug} output
26790 of a package when they need it. For instance, the following command
26791 installs the debugging information for the GNU C Library and for GNU
26795 guix install glibc:debug guile:debug
26798 GDB must then be told to look for debug files in the user's profile, by
26799 setting the @code{debug-file-directory} variable (consider setting it
26800 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
26804 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
26807 From there on, GDB will pick up debugging information from the
26808 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
26810 In addition, you will most likely want GDB to be able to show the source
26811 code being debugged. To do that, you will have to unpack the source
26812 code of the package of interest (obtained with @code{guix build
26813 --source}, @pxref{Invoking guix build}), and to point GDB to that source
26814 directory using the @code{directory} command (@pxref{Source Path,
26815 @code{directory},, gdb, Debugging with GDB}).
26817 @c XXX: keep me up-to-date
26818 The @code{debug} output mechanism in Guix is implemented by the
26819 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
26820 opt-in---debugging information is available only for the packages
26821 with definitions explicitly declaring a @code{debug} output. This may be
26822 changed to opt-out in the future if our build farm servers can handle
26823 the load. To check whether a package has a @code{debug} output, use
26824 @command{guix package --list-available} (@pxref{Invoking guix package}).
26827 @node Security Updates
26828 @chapter Security Updates
26830 @cindex security updates
26831 @cindex security vulnerabilities
26832 Occasionally, important security vulnerabilities are discovered in software
26833 packages and must be patched. Guix developers try hard to keep track of
26834 known vulnerabilities and to apply fixes as soon as possible in the
26835 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
26836 containing only security updates.) The @command{guix lint} tool helps
26837 developers find out about vulnerable versions of software packages in the
26842 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
26843 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
26844 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
26848 @xref{Invoking guix lint}, for more information.
26850 Guix follows a functional
26851 package management discipline (@pxref{Introduction}), which implies
26852 that, when a package is changed, @emph{every package that depends on it}
26853 must be rebuilt. This can significantly slow down the deployment of
26854 fixes in core packages such as libc or Bash, since basically the whole
26855 distribution would need to be rebuilt. Using pre-built binaries helps
26856 (@pxref{Substitutes}), but deployment may still take more time than
26860 To address this, Guix implements @dfn{grafts}, a mechanism that allows
26861 for fast deployment of critical updates without the costs associated
26862 with a whole-distribution rebuild. The idea is to rebuild only the
26863 package that needs to be patched, and then to ``graft'' it onto packages
26864 explicitly installed by the user and that were previously referring to
26865 the original package. The cost of grafting is typically very low, and
26866 order of magnitudes lower than a full rebuild of the dependency chain.
26868 @cindex replacements of packages, for grafts
26869 For instance, suppose a security update needs to be applied to Bash.
26870 Guix developers will provide a package definition for the ``fixed''
26871 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
26872 Packages}). Then, the original package definition is augmented with a
26873 @code{replacement} field pointing to the package containing the bug fix:
26880 (replacement bash-fixed)))
26883 From there on, any package depending directly or indirectly on Bash---as
26884 reported by @command{guix gc --requisites} (@pxref{Invoking guix
26885 gc})---that is installed is automatically ``rewritten'' to refer to
26886 @code{bash-fixed} instead of @code{bash}. This grafting process takes
26887 time proportional to the size of the package, usually less than a
26888 minute for an ``average'' package on a recent machine. Grafting is
26889 recursive: when an indirect dependency requires grafting, then grafting
26890 ``propagates'' up to the package that the user is installing.
26892 Currently, the length of the name and version of the graft and that of
26893 the package it replaces (@code{bash-fixed} and @code{bash} in the example
26894 above) must be equal. This restriction mostly comes from the fact that
26895 grafting works by patching files, including binary files, directly.
26896 Other restrictions may apply: for instance, when adding a graft to a
26897 package providing a shared library, the original shared library and its
26898 replacement must have the same @code{SONAME} and be binary-compatible.
26900 The @option{--no-grafts} command-line option allows you to forcefully
26901 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
26905 guix build bash --no-grafts
26909 returns the store file name of the original Bash, whereas:
26916 returns the store file name of the ``fixed'', replacement Bash. This
26917 allows you to distinguish between the two variants of Bash.
26919 To verify which Bash your whole profile refers to, you can run
26920 (@pxref{Invoking guix gc}):
26923 guix gc -R `readlink -f ~/.guix-profile` | grep bash
26927 @dots{} and compare the store file names that you get with those above.
26928 Likewise for a complete Guix system generation:
26931 guix gc -R `guix system build my-config.scm` | grep bash
26934 Lastly, to check which Bash running processes are using, you can use the
26935 @command{lsof} command:
26938 lsof | grep /gnu/store/.*bash
26942 @node Bootstrapping
26943 @chapter Bootstrapping
26945 @c Adapted from the ELS 2013 paper.
26947 @cindex bootstrapping
26949 Bootstrapping in our context refers to how the distribution gets built
26950 ``from nothing''. Remember that the build environment of a derivation
26951 contains nothing but its declared inputs (@pxref{Introduction}). So
26952 there's an obvious chicken-and-egg problem: how does the first package
26953 get built? How does the first compiler get compiled? Note that this is
26954 a question of interest only to the curious hacker, not to the regular
26955 user, so you can shamelessly skip this section if you consider yourself
26956 a ``regular user''.
26958 @cindex bootstrap binaries
26959 The GNU system is primarily made of C code, with libc at its core. The
26960 GNU build system itself assumes the availability of a Bourne shell and
26961 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
26962 `grep'. Furthermore, build programs---programs that run
26963 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
26964 (@pxref{Derivations}). Consequently, to be able to build anything at
26965 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
26966 Binutils, libc, and the other packages mentioned above---the
26967 @dfn{bootstrap binaries}.
26969 These bootstrap binaries are ``taken for granted'', though we can also
26970 re-create them if needed (more on that later).
26972 For @code{i686-linux} and @code{x86_64-linux} the Guix bootstrap process is
26973 more elaborate, @pxref{Reduced Binary Seed Bootstrap}.
26976 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
26977 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
26980 @node Reduced Binary Seed Bootstrap
26981 @section The Reduced Binary Seed Bootstrap
26983 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
26984 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
26985 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
26986 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
26987 ``taken for granted.''
26989 Taking these binaries for granted means that we consider them to be a correct
26990 and trustworthy `seed' for building the complete system. Therein lies a
26991 problem: the current combined size of these bootstrap binaries is about 250MB
26992 (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing or even inspecting
26993 these is next to impossible.
26995 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a ``Reduced
26996 Binary Seed'' bootstrap @footnote{We would like to say: ``Full Source
26997 Bootstrap'' and while we are working towards that goal it would be hyperbole
26998 to use that term for what we do now.}.
27000 The Reduced Binary Seed bootstrap removes the most critical tools---from a
27001 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
27002 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
27003 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
27004 written in Scheme and the Mes C Library, built for TinyCC and for GCC). Using
27005 these new binary seeds and a new set of
27007 packages@footnote{@c
27022 gcc-mesboot1-wrapper,
27023 glibc-headers-mesboot,
27027 gcc-mesboot-wrapper.
27030 the ``missing'' Binutils, GCC, and the GNU C Library are built from source.
27031 From here on the more traditional bootstrap process resumes. This approach
27032 has reduced the bootstrap binaries in size to about 130MB. Work is ongoing to
27033 reduce this further. If you are interested, join us on @code{#bootstrappable}
27034 on the Freenode IRC network.
27036 @c ./pre-inst-env guix graph --type=bag -e '(begin (use-modules (guix packages)) (%current-system "i686-linux") (@@ (gnu packages commencement) gcc-mesboot))' > doc/images/gcc-mesboot-bag-graph.dot
27037 @c dot -T png doc/images/gcc-mesboot-bag-graph.dot > doc/images/gcc-mesboot-bag-graph.png
27039 Below is the generated dependency graph for @code{gcc-mesboot}, the bootstrap
27040 compiler used to build the rest of GuixSD.
27042 @image{images/gcc-mesboot-bag-graph,6in,,Dependency graph of the gcc-mesboot}
27044 @node Preparing to Use the Bootstrap Binaries
27045 @section Preparing to Use the Bootstrap Binaries
27047 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
27048 @c large image, it's hard to scroll. Oh well.
27049 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
27051 The figure above shows the very beginning of the dependency graph of the
27052 distribution, corresponding to the package definitions of the @code{(gnu
27053 packages bootstrap)} module. A similar figure can be generated with
27054 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
27057 guix graph -t derivation \
27058 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
27059 | dot -Tps > gcc.ps
27062 or, for the Reduced Binary Seed bootstrap
27065 guix graph -t derivation \
27066 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
27067 | dot -Tps > mes.ps
27070 At this level of detail, things are
27071 slightly complex. First, Guile itself consists of an ELF executable,
27072 along with many source and compiled Scheme files that are dynamically
27073 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
27074 tarball shown in this graph. This tarball is part of Guix's ``source''
27075 distribution, and gets inserted into the store with @code{add-to-store}
27076 (@pxref{The Store}).
27078 But how do we write a derivation that unpacks this tarball and adds it
27079 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
27080 derivation---the first one that gets built---uses @code{bash} as its
27081 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
27082 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
27083 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
27084 the Guix source distribution, whose sole purpose is to allow the Guile
27085 tarball to be unpacked.
27087 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
27088 Guile that can be used to run subsequent build programs. Its first task
27089 is to download tarballs containing the other pre-built binaries---this
27090 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
27091 @code{ftp-client.scm} are used for this purpose. The
27092 @code{module-import.drv} derivations import those modules in a directory
27093 in the store, using the original layout. The
27094 @code{module-import-compiled.drv} derivations compile those modules, and
27095 write them in an output directory with the right layout. This
27096 corresponds to the @code{#:modules} argument of
27097 @code{build-expression->derivation} (@pxref{Derivations}).
27099 Finally, the various tarballs are unpacked by the derivations
27100 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
27101 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
27102 point we have a working C tool chain.
27104 @unnumberedsec Building the Build Tools
27106 Bootstrapping is complete when we have a full tool chain that does not
27107 depend on the pre-built bootstrap tools discussed above. This
27108 no-dependency requirement is verified by checking whether the files of
27109 the final tool chain contain references to the @file{/gnu/store}
27110 directories of the bootstrap inputs. The process that leads to this
27111 ``final'' tool chain is described by the package definitions found in
27112 the @code{(gnu packages commencement)} module.
27114 The @command{guix graph} command allows us to ``zoom out'' compared to
27115 the graph above, by looking at the level of package objects instead of
27116 individual derivations---remember that a package may translate to
27117 several derivations, typically one derivation to download its source,
27118 one to build the Guile modules it needs, and one to actually build the
27119 package from source. The command:
27122 guix graph -t bag \
27123 -e '(@@@@ (gnu packages commencement)
27124 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
27128 produces the dependency graph leading to the ``final'' C
27129 library@footnote{You may notice the @code{glibc-intermediate} label,
27130 suggesting that it is not @emph{quite} final, but as a good
27131 approximation, we will consider it final.}, depicted below.
27133 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
27135 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
27136 The first tool that gets built with the bootstrap binaries is
27137 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
27138 for all the following packages. From there Findutils and Diffutils get
27141 Then come the first-stage Binutils and GCC, built as pseudo cross
27142 tools---i.e., with @code{--target} equal to @code{--host}. They are
27143 used to build libc. Thanks to this cross-build trick, this libc is
27144 guaranteed not to hold any reference to the initial tool chain.
27146 From there the final Binutils and GCC (not shown above) are built.
27148 from the final Binutils, and links programs against the just-built libc.
27149 This tool chain is used to build the other packages used by Guix and by
27150 the GNU Build System: Guile, Bash, Coreutils, etc.
27152 And voilà! At this point we have the complete set of build tools that
27153 the GNU Build System expects. These are in the @code{%final-inputs}
27154 variable of the @code{(gnu packages commencement)} module, and are
27155 implicitly used by any package that uses @code{gnu-build-system}
27156 (@pxref{Build Systems, @code{gnu-build-system}}).
27159 @unnumberedsec Building the Bootstrap Binaries
27161 @cindex bootstrap binaries
27162 Because the final tool chain does not depend on the bootstrap binaries,
27163 those rarely need to be updated. Nevertheless, it is useful to have an
27164 automated way to produce them, should an update occur, and this is what
27165 the @code{(gnu packages make-bootstrap)} module provides.
27167 The following command builds the tarballs containing the bootstrap binaries
27168 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
27169 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
27170 and Guile, and a tarball containing a mixture of Coreutils and other basic
27171 command-line tools):
27174 guix build bootstrap-tarballs
27177 The generated tarballs are those that should be referred to in the
27178 @code{(gnu packages bootstrap)} module mentioned at the beginning of
27181 Still here? Then perhaps by now you've started to wonder: when do we
27182 reach a fixed point? That is an interesting question! The answer is
27183 unknown, but if you would like to investigate further (and have
27184 significant computational and storage resources to do so), then let us
27187 @unnumberedsec Reducing the Set of Bootstrap Binaries
27189 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
27190 binary code! Why is that a problem? It's a problem because these big chunks
27191 of binary code are practically non-auditable, which makes it hard to establish
27192 what source code produced them. Every unauditable binary also leaves us
27193 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
27194 paper @emph{Reflections on Trusting Trust}.
27196 This is mitigated by the fact that our bootstrap binaries were generated
27197 from an earlier Guix revision. Nevertheless it lacks the level of
27198 transparency that we get in the rest of the package dependency graph,
27199 where Guix always gives us a source-to-binary mapping. Thus, our goal
27200 is to reduce the set of bootstrap binaries to the bare minimum.
27202 The @uref{http://bootstrappable.org, Bootstrappable.org web site} lists
27203 on-going projects to do that. One of these is about replacing the
27204 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
27205 of increasing complexity, which could be built from source starting from
27206 a simple and auditable assembler.
27208 Our first major achievement is the replacement of of GCC, the GNU C Library
27209 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
27210 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
27211 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
27212 bootstrapped yet and thus we inject them as binary seeds. We call this the
27213 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
27214 binaries! Also, it has eliminated the C compiler binary; i686-linux and
27215 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
27217 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
27218 also looking at any other bootstrap binaries. Your help is welcome!
27221 @chapter Porting to a New Platform
27223 As discussed above, the GNU distribution is self-contained, and
27224 self-containment is achieved by relying on pre-built ``bootstrap
27225 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
27226 operating system kernel, CPU architecture, and application binary
27227 interface (ABI). Thus, to port the distribution to a platform that is
27228 not yet supported, one must build those bootstrap binaries, and update
27229 the @code{(gnu packages bootstrap)} module to use them on that platform.
27231 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
27232 When everything goes well, and assuming the GNU tool chain supports the
27233 target platform, this can be as simple as running a command like this
27237 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
27240 For this to work, the @code{glibc-dynamic-linker} procedure in
27241 @code{(gnu packages bootstrap)} must be augmented to return the right
27242 file name for libc's dynamic linker on that platform; likewise,
27243 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
27244 taught about the new platform.
27246 Once these are built, the @code{(gnu packages bootstrap)} module needs
27247 to be updated to refer to these binaries on the target platform. That
27248 is, the hashes and URLs of the bootstrap tarballs for the new platform
27249 must be added alongside those of the currently supported platforms. The
27250 bootstrap Guile tarball is treated specially: it is expected to be
27251 available locally, and @file{gnu/local.mk} has rules to download it for
27252 the supported architectures; a rule for the new platform must be added
27255 In practice, there may be some complications. First, it may be that the
27256 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
27257 above) is not recognized by all the GNU tools. Typically, glibc
27258 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
27259 configure flag (see @code{gcc.scm} for examples of how to handle this).
27260 Second, some of the required packages could fail to build for that
27261 platform. Lastly, the generated binaries could be broken for some
27264 @c *********************************************************************
27265 @include contributing.texi
27267 @c *********************************************************************
27268 @node Acknowledgments
27269 @chapter Acknowledgments
27271 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
27272 which was designed and
27273 implemented by Eelco Dolstra, with contributions from other people (see
27274 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
27275 management, and promoted unprecedented features, such as transactional
27276 package upgrades and rollbacks, per-user profiles, and referentially
27277 transparent build processes. Without this work, Guix would not exist.
27279 The Nix-based software distributions, Nixpkgs and NixOS, have also been
27280 an inspiration for Guix.
27282 GNU@tie{}Guix itself is a collective work with contributions from a
27283 number of people. See the @file{AUTHORS} file in Guix for more
27284 information on these fine people. The @file{THANKS} file lists people
27285 who have helped by reporting bugs, taking care of the infrastructure,
27286 providing artwork and themes, making suggestions, and more---thank you!
27289 @c *********************************************************************
27290 @node GNU Free Documentation License
27291 @appendix GNU Free Documentation License
27292 @cindex license, GNU Free Documentation License
27293 @include fdl-1.3.texi
27295 @c *********************************************************************
27296 @node Concept Index
27297 @unnumbered Concept Index
27300 @node Programming Index
27301 @unnumbered Programming Index
27302 @syncodeindex tp fn
27303 @syncodeindex vr fn
27308 @c Local Variables:
27309 @c ispell-local-dictionary: "american";