6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
14 @set KEY-SERVER pool.sks-keyservers.net
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER ci.guix.gnu.org
21 @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
24 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès@*
25 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
26 Copyright @copyright{} 2013 Nikita Karetnikov@*
27 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
28 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
29 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
30 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
31 Copyright @copyright{} 2015, 2016, 2017 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 ng0@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017 Christopher Allan Webber@*
49 Copyright @copyright{} 2017, 2018 Marius Bakke@*
50 Copyright @copyright{} 2017 Hartmut Goebel@*
51 Copyright @copyright{} 2017 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018 Tobias Geerinckx-Rice@*
53 Copyright @copyright{} 2017 George Clemmer@*
54 Copyright @copyright{} 2017 Andy Wingo@*
55 Copyright @copyright{} 2017, 2018, 2019 Arun Isaac@*
56 Copyright @copyright{} 2017 nee@*
57 Copyright @copyright{} 2018 Rutger Helling@*
58 Copyright @copyright{} 2018 Oleg Pykhalov@*
59 Copyright @copyright{} 2018 Mike Gerwitz@*
60 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
61 Copyright @copyright{} 2018 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@*
68 Permission is granted to copy, distribute and/or modify this document
69 under the terms of the GNU Free Documentation License, Version 1.3 or
70 any later version published by the Free Software Foundation; with no
71 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
72 copy of the license is included in the section entitled ``GNU Free
73 Documentation License''.
76 @dircategory System administration
78 * Guix: (guix). Manage installed software and system configuration.
79 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
80 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
81 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
82 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
85 @dircategory Software development
87 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
88 * guix build: (guix)Invoking guix build. Building packages.
89 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
93 @title GNU Guix Reference Manual
94 @subtitle Using the GNU Guix Functional Package Manager
95 @author The GNU Guix Developers
98 @vskip 0pt plus 1filll
99 Edition @value{EDITION} @*
107 @c *********************************************************************
111 This document describes GNU Guix version @value{VERSION}, a functional
112 package management tool written for the GNU system.
114 @c TRANSLATORS: You can replace the following paragraph with information on
115 @c how to join your own translation team and how to report issues with the
117 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
118 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
119 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
120 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
121 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
122 would like to translate it in your native language, consider joining the
123 @uref{https://translationproject.org/domain/guix-manual.html, Translation
127 * Introduction:: What is Guix about?
128 * Installation:: Installing Guix.
129 * System Installation:: Installing the whole operating system.
130 * Package Management:: Package installation, upgrade, etc.
131 * Development:: Guix-aided software development.
132 * Programming Interface:: Using Guix in Scheme.
133 * Utilities:: Package management commands.
134 * System Configuration:: Configuring the operating system.
135 * Documentation:: Browsing software user manuals.
136 * Installing Debugging Files:: Feeding the debugger.
137 * Security Updates:: Deploying security fixes quickly.
138 * Bootstrapping:: GNU/Linux built from scratch.
139 * Porting:: Targeting another platform or kernel.
140 * Contributing:: Your help needed!
142 * Acknowledgments:: Thanks!
143 * GNU Free Documentation License:: The license of this manual.
144 * Concept Index:: Concepts.
145 * Programming Index:: Data types, functions, and variables.
148 --- The Detailed Node Listing ---
152 * Managing Software the Guix Way:: What's special.
153 * GNU Distribution:: The packages and tools.
157 * Binary Installation:: Getting Guix running in no time!
158 * Requirements:: Software needed to build and run Guix.
159 * Running the Test Suite:: Testing Guix.
160 * Setting Up the Daemon:: Preparing the build daemon's environment.
161 * Invoking guix-daemon:: Running the build daemon.
162 * Application Setup:: Application-specific setup.
164 Setting Up the Daemon
166 * Build Environment Setup:: Preparing the isolated build environment.
167 * Daemon Offload Setup:: Offloading builds to remote machines.
168 * SELinux Support:: Using an SELinux policy for the daemon.
172 * Limitations:: What you can expect.
173 * Hardware Considerations:: Supported hardware.
174 * USB Stick and DVD Installation:: Preparing the installation medium.
175 * Preparing for Installation:: Networking, partitioning, etc.
176 * Guided Graphical Installation:: Easy graphical installation.
177 * Manual Installation:: Manual installation for wizards.
178 * After System Installation:: When installation succeeded.
179 * Installing Guix in a VM:: Guix System playground.
180 * Building the Installation Image:: How this comes to be.
184 * Keyboard Layout and Networking and Partitioning:: Initial setup.
185 * Proceeding with the Installation:: Installing.
189 * Features:: How Guix will make your life brighter.
190 * Invoking guix package:: Package installation, removal, etc.
191 * Substitutes:: Downloading pre-built binaries.
192 * Packages with Multiple Outputs:: Single source package, multiple outputs.
193 * Invoking guix gc:: Running the garbage collector.
194 * Invoking guix pull:: Fetching the latest Guix and distribution.
195 * Channels:: Customizing the package collection.
196 * Inferiors:: Interacting with another revision of Guix.
197 * Invoking guix describe:: Display information about your Guix revision.
198 * Invoking guix archive:: Exporting and importing store files.
202 * Official Substitute Server:: One particular source of substitutes.
203 * Substitute Server Authorization:: How to enable or disable substitutes.
204 * Substitute Authentication:: How Guix verifies substitutes.
205 * Proxy Settings:: How to get substitutes via proxy.
206 * Substitution Failure:: What happens when substitution fails.
207 * On Trusting Binaries:: How can you trust that binary blob?
211 * Invoking guix environment:: Setting up development environments.
212 * Invoking guix pack:: Creating software bundles.
214 Programming Interface
216 * Package Modules:: Packages from the programmer's viewpoint.
217 * Defining Packages:: Defining new packages.
218 * Build Systems:: Specifying how packages are built.
219 * The Store:: Manipulating the package store.
220 * Derivations:: Low-level interface to package derivations.
221 * The Store Monad:: Purely functional interface to the store.
222 * G-Expressions:: Manipulating build expressions.
223 * Invoking guix repl:: Fiddling with Guix interactively.
227 * package Reference:: The package data type.
228 * origin Reference:: The origin data type.
232 * Invoking guix build:: Building packages from the command line.
233 * Invoking guix edit:: Editing package definitions.
234 * Invoking guix download:: Downloading a file and printing its hash.
235 * Invoking guix hash:: Computing the cryptographic hash of a file.
236 * Invoking guix import:: Importing package definitions.
237 * Invoking guix refresh:: Updating package definitions.
238 * Invoking guix lint:: Finding errors in package definitions.
239 * Invoking guix size:: Profiling disk usage.
240 * Invoking guix graph:: Visualizing the graph of packages.
241 * Invoking guix publish:: Sharing substitutes.
242 * Invoking guix challenge:: Challenging substitute servers.
243 * Invoking guix copy:: Copying to and from a remote store.
244 * Invoking guix container:: Process isolation.
245 * Invoking guix weather:: Assessing substitute availability.
246 * Invoking guix processes:: Listing client processes.
248 Invoking @command{guix build}
250 * Common Build Options:: Build options for most commands.
251 * Package Transformation Options:: Creating variants of packages.
252 * Additional Build Options:: Options specific to 'guix build'.
253 * Debugging Build Failures:: Real life packaging experience.
257 * Using the Configuration System:: Customizing your GNU system.
258 * operating-system Reference:: Detail of operating-system declarations.
259 * File Systems:: Configuring file system mounts.
260 * Mapped Devices:: Block device extra processing.
261 * User Accounts:: Specifying user accounts.
262 * Keyboard Layout:: How the system interprets key strokes.
263 * Locales:: Language and cultural convention settings.
264 * Services:: Specifying system services.
265 * Setuid Programs:: Programs running with root privileges.
266 * X.509 Certificates:: Authenticating HTTPS servers.
267 * Name Service Switch:: Configuring libc's name service switch.
268 * Initial RAM Disk:: Linux-Libre bootstrapping.
269 * Bootloader Configuration:: Configuring the boot loader.
270 * Invoking guix system:: Instantiating a system configuration.
271 * Running Guix in a VM:: How to run Guix System in a virtual machine.
272 * Defining Services:: Adding new service definitions.
276 * Base Services:: Essential system services.
277 * Scheduled Job Execution:: The mcron service.
278 * Log Rotation:: The rottlog service.
279 * Networking Services:: Network setup, SSH daemon, etc.
280 * X Window:: Graphical display.
281 * Printing Services:: Local and remote printer support.
282 * Desktop Services:: D-Bus and desktop services.
283 * Sound Services:: ALSA and Pulseaudio services.
284 * Database Services:: SQL databases, key-value stores, etc.
285 * Mail Services:: IMAP, POP3, SMTP, and all that.
286 * Messaging Services:: Messaging services.
287 * Telephony Services:: Telephony services.
288 * Monitoring Services:: Monitoring services.
289 * Kerberos Services:: Kerberos services.
290 * Web Services:: Web servers.
291 * Certificate Services:: TLS certificates via Let's Encrypt.
292 * DNS Services:: DNS daemons.
293 * VPN Services:: VPN daemons.
294 * Network File System:: NFS related services.
295 * Continuous Integration:: The Cuirass service.
296 * Power Management Services:: Extending battery life.
297 * Audio Services:: The MPD.
298 * Virtualization Services:: Virtualization services.
299 * Version Control Services:: Providing remote access to Git repositories.
300 * Game Services:: Game servers.
301 * Miscellaneous Services:: Other services.
305 * Service Composition:: The model for composing services.
306 * Service Types and Services:: Types and services.
307 * Service Reference:: API reference.
308 * Shepherd Services:: A particular type of service.
313 @c *********************************************************************
315 @chapter Introduction
318 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
319 using the international phonetic alphabet (IPA).} is a package
320 management tool for and distribution of the GNU system.
321 Guix makes it easy for unprivileged
322 users to install, upgrade, or remove software packages, to roll back to a
323 previous package set, to build packages from source, and generally
324 assists with the creation and maintenance of software environments.
327 @cindex GuixSD, now Guix System
328 @cindex Guix System Distribution, now Guix System
329 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
330 complements the available tools without interference (@pxref{Installation}),
331 or you can use it as a standalone operating system distribution,
332 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
333 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
334 group everything under the ``Guix'' banner since, after all, Guix System is
335 readily available through the @command{guix system} command, even if you're
336 using a different distro underneath!}. @xref{GNU Distribution}.
339 * Managing Software the Guix Way:: What's special.
340 * GNU Distribution:: The packages and tools.
343 @node Managing Software the Guix Way
344 @section Managing Software the Guix Way
346 @cindex user interfaces
347 Guix provides a command-line package management interface
348 (@pxref{Package Management}), tools to help with software development
349 (@pxref{Development}), command-line utilities for more advanced usage,
350 (@pxref{Utilities}), as well as Scheme programming interfaces
351 (@pxref{Programming Interface}).
353 Its @dfn{build daemon} is responsible for building packages on behalf of
354 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
355 binaries from authorized sources (@pxref{Substitutes}).
357 @cindex extensibility of the distribution
358 @cindex customization, of packages
359 Guix includes package definitions for many GNU and non-GNU packages, all
360 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
361 user's computing freedom}. It is @emph{extensible}: users can write
362 their own package definitions (@pxref{Defining Packages}) and make them
363 available as independent package modules (@pxref{Package Modules}). It
364 is also @emph{customizable}: users can @emph{derive} specialized package
365 definitions from existing ones, including from the command line
366 (@pxref{Package Transformation Options}).
368 @cindex functional package management
370 Under the hood, Guix implements the @dfn{functional package management}
371 discipline pioneered by Nix (@pxref{Acknowledgments}).
372 In Guix, the package build and installation process is seen
373 as a @emph{function}, in the mathematical sense. That function takes inputs,
374 such as build scripts, a compiler, and libraries, and
375 returns an installed package. As a pure function, its result depends
376 solely on its inputs---for instance, it cannot refer to software or
377 scripts that were not explicitly passed as inputs. A build function
378 always produces the same result when passed a given set of inputs. It
379 cannot alter the environment of the running system in
380 any way; for instance, it cannot create, modify, or delete files outside
381 of its build and installation directories. This is achieved by running
382 build processes in isolated environments (or @dfn{containers}), where only their
383 explicit inputs are visible.
386 The result of package build functions is @dfn{cached} in the file
387 system, in a special directory called @dfn{the store} (@pxref{The
388 Store}). Each package is installed in a directory of its own in the
389 store---by default under @file{/gnu/store}. The directory name contains
390 a hash of all the inputs used to build that package; thus, changing an
391 input yields a different directory name.
393 This approach is the foundation for the salient features of Guix: support
394 for transactional package upgrade and rollback, per-user installation, and
395 garbage collection of packages (@pxref{Features}).
398 @node GNU Distribution
399 @section GNU Distribution
402 Guix comes with a distribution of the GNU system consisting entirely of
403 free software@footnote{The term ``free'' here refers to the
404 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
405 users of that software}.}. The
406 distribution can be installed on its own (@pxref{System Installation}),
407 but it is also possible to install Guix as a package manager on top of
408 an installed GNU/Linux system (@pxref{Installation}). When we need to
409 distinguish between the two, we refer to the standalone distribution as
412 The distribution provides core GNU packages such as GNU libc, GCC, and
413 Binutils, as well as many GNU and non-GNU applications. The complete
414 list of available packages can be browsed
415 @url{https://www.gnu.org/software/guix/packages,on-line} or by
416 running @command{guix package} (@pxref{Invoking guix package}):
419 guix package --list-available
422 Our goal is to provide a practical 100% free software distribution of
423 Linux-based and other variants of GNU, with a focus on the promotion and
424 tight integration of GNU components, and an emphasis on programs and
425 tools that help users exert that freedom.
427 Packages are currently available on the following platforms:
432 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
435 Intel 32-bit architecture (IA32), Linux-Libre kernel;
438 ARMv7-A architecture with hard float, Thumb-2 and NEON,
439 using the EABI hard-float application binary interface (ABI),
440 and Linux-Libre kernel.
443 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
446 little-endian 64-bit MIPS processors, specifically the Loongson series,
447 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
448 supported; in particular, the project's build farms no longer provide
449 substitutes for this architecture.
453 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
454 configuration and Guix takes care of instantiating the configuration in a
455 transactional, reproducible, and stateless fashion (@pxref{System
456 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
457 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
458 Manual}), the well-known GNU utilities and tool chain, as well as the
459 graphical environment or system services of your choice.
461 Guix System is available on all the above platforms except
462 @code{mips64el-linux}.
465 For information on porting to other architectures or kernels,
468 Building this distribution is a cooperative effort, and you are invited
469 to join! @xref{Contributing}, for information about how you can help.
472 @c *********************************************************************
474 @chapter Installation
476 @cindex installing Guix
479 We recommend the use of this
480 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
481 shell installer script} to install Guix on top of a running GNU/Linux system,
482 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
483 with the installation of the package manager, which can be done on top of a
484 running GNU/Linux system. If, instead, you want to install the complete GNU
485 operating system, @pxref{System Installation}.} The script automates the
486 download, installation, and initial configuration of Guix. It should be run
490 @cindex foreign distro
491 @cindex directories related to foreign distro
492 When installed on a foreign distro, GNU@tie{}Guix complements the available
493 tools without interference. Its data lives exclusively in two directories,
494 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
495 such as @file{/etc}, are left untouched.
497 Once installed, Guix can be updated by running @command{guix pull}
498 (@pxref{Invoking guix pull}).
500 If you prefer to perform the installation steps manually or want to tweak
501 them, you may find the following subsections useful. They describe the
502 software requirements of Guix, as well as how to install it manually and get
506 * Binary Installation:: Getting Guix running in no time!
507 * Requirements:: Software needed to build and run Guix.
508 * Running the Test Suite:: Testing Guix.
509 * Setting Up the Daemon:: Preparing the build daemon's environment.
510 * Invoking guix-daemon:: Running the build daemon.
511 * Application Setup:: Application-specific setup.
514 @node Binary Installation
515 @section Binary Installation
517 @cindex installing Guix from binaries
518 @cindex installer script
519 This section describes how to install Guix on an arbitrary system from a
520 self-contained tarball providing binaries for Guix and for all its
521 dependencies. This is often quicker than installing from source, which
522 is described in the next sections. The only requirement is to have
525 @c Note duplicated from the ``Installation'' node.
527 We recommend the use of this
528 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
529 shell installer script}. The script automates the download, installation, and
530 initial configuration steps described below. It should be run as the root
534 Installing goes along these lines:
538 @cindex downloading Guix binary
539 Download the binary tarball from
540 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz},
541 where @var{system} is @code{x86_64-linux} for an @code{x86_64} machine
542 already running the kernel Linux, and so on.
544 @c The following is somewhat duplicated in ``System Installation''.
545 Make sure to download the associated @file{.sig} file and to verify the
546 authenticity of the tarball against it, along these lines:
549 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
550 $ gpg --verify guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
553 If that command fails because you do not have the required public key,
554 then run this command to import it:
557 $ gpg --keyserver @value{KEY-SERVER} \
558 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
562 and rerun the @code{gpg --verify} command.
563 @c end authentication part
566 Now, you need to become the @code{root} user. Depending on your distribution,
567 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
571 # tar --warning=no-timestamp -xf \
572 guix-binary-@value{VERSION}.@var{system}.tar.xz
573 # mv var/guix /var/ && mv gnu /
576 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
577 The latter contains a ready-to-use profile for @code{root} (see next
580 Do @emph{not} unpack the tarball on a working Guix system since that
581 would overwrite its own essential files.
583 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
584 not emit warnings about ``implausibly old time stamps'' (such
585 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
587 They stem from the fact that all the
588 files in the archive have their modification time set to zero (which
589 means January 1st, 1970.) This is done on purpose to make sure the
590 archive content is independent of its creation time, thus making it
594 Make the profile available under @file{~root/.config/guix/current}, which is
595 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
598 # mkdir -p ~root/.config/guix
599 # ln -sf /var/guix/profiles/per-user/root/current-guix \
600 ~root/.config/guix/current
603 Source @file{etc/profile} to augment @code{PATH} and other relevant
604 environment variables:
607 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
608 source $GUIX_PROFILE/etc/profile
612 Create the group and user accounts for build users as explained below
613 (@pxref{Build Environment Setup}).
616 Run the daemon, and set it to automatically start on boot.
618 If your host distro uses the systemd init system, this can be achieved
621 @c Versions of systemd that supported symlinked service files are not
622 @c yet widely deployed, so we should suggest that users copy the service
625 @c See this thread for more information:
626 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
629 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
631 # systemctl start guix-daemon && systemctl enable guix-daemon
634 If your host distro uses the Upstart init system:
637 # initctl reload-configuration
638 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
643 Otherwise, you can still start the daemon manually with:
646 # ~root/.config/guix/current/bin/guix-daemon \
647 --build-users-group=guixbuild
651 Make the @command{guix} command available to other users on the machine,
655 # mkdir -p /usr/local/bin
657 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
660 It is also a good idea to make the Info version of this manual available
664 # mkdir -p /usr/local/share/info
665 # cd /usr/local/share/info
666 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
670 That way, assuming @file{/usr/local/share/info} is in the search path,
671 running @command{info guix} will open this manual (@pxref{Other Info
672 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
676 @cindex substitutes, authorization thereof
677 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
678 (@pxref{Substitutes}), authorize them:
681 # guix archive --authorize < \
682 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
686 Each user may need to perform a few additional steps to make their Guix
687 environment ready for use, @pxref{Application Setup}.
690 Voilà, the installation is complete!
692 You can confirm that Guix is working by installing a sample package into
699 The binary installation tarball can be (re)produced and verified simply
700 by running the following command in the Guix source tree:
703 make guix-binary.@var{system}.tar.xz
707 ...@: which, in turn, runs:
710 guix pack -s @var{system} --localstatedir \
711 --profile-name=current-guix guix
714 @xref{Invoking guix pack}, for more info on this handy tool.
717 @section Requirements
719 This section lists requirements when building Guix from source. The
720 build procedure for Guix is the same as for other GNU software, and is
721 not covered here. Please see the files @file{README} and @file{INSTALL}
722 in the Guix source tree for additional details.
724 @cindex official website
725 GNU Guix is available for download from its website at
726 @url{https://www.gnu.org/software/guix/}.
728 GNU Guix depends on the following packages:
731 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 2.2.x;
732 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
735 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
736 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
737 Guile,, gnutls-guile, GnuTLS-Guile});
739 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
742 @c FIXME: Specify a version number once a release has been made.
743 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
745 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON};
746 @item @url{https://zlib.net, zlib};
747 @item @url{https://www.gnu.org/software/make/, GNU Make}.
750 The following dependencies are optional:
754 @c Note: We need at least 0.10.2 for 'channel-send-eof'.
755 Support for build offloading (@pxref{Daemon Offload Setup}) and
756 @command{guix copy} (@pxref{Invoking guix copy}) depends on
757 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
758 version 0.10.2 or later.
761 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
762 substitutes can be used and @command{guix publish} can compress substitutes
766 When @url{http://www.bzip.org, libbz2} is available,
767 @command{guix-daemon} can use it to compress build logs.
770 Unless @code{--disable-daemon} was passed to @command{configure}, the
771 following packages are also needed:
774 @item @url{https://gnupg.org/, GNU libgcrypt};
775 @item @url{https://sqlite.org, SQLite 3};
776 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
780 @cindex state directory
781 When configuring Guix on a system that already has a Guix installation,
782 be sure to specify the same state directory as the existing installation
783 using the @code{--localstatedir} option of the @command{configure}
784 script (@pxref{Directory Variables, @code{localstatedir},, standards,
785 GNU Coding Standards}). The @command{configure} script protects against
786 unintended misconfiguration of @var{localstatedir} so you do not
787 inadvertently corrupt your store (@pxref{The Store}).
789 @cindex Nix, compatibility
790 When a working installation of @url{https://nixos.org/nix/, the Nix package
791 manager} is available, you
792 can instead configure Guix with @code{--disable-daemon}. In that case,
793 Nix replaces the three dependencies above.
795 Guix is compatible with Nix, so it is possible to share the same store
796 between both. To do so, you must pass @command{configure} not only the
797 same @code{--with-store-dir} value, but also the same
798 @code{--localstatedir} value. The latter is essential because it
799 specifies where the database that stores metadata about the store is
800 located, among other things. The default values for Nix are
801 @code{--with-store-dir=/nix/store} and @code{--localstatedir=/nix/var}.
802 Note that @code{--disable-daemon} is not required if
803 your goal is to share the store with Nix.
805 @node Running the Test Suite
806 @section Running the Test Suite
809 After a successful @command{configure} and @code{make} run, it is a good
810 idea to run the test suite. It can help catch issues with the setup or
811 environment, or bugs in Guix itself---and really, reporting test
812 failures is a good way to help improve the software. To run the test
819 Test cases can run in parallel: you can use the @code{-j} option of
820 GNU@tie{}make to speed things up. The first run may take a few minutes
821 on a recent machine; subsequent runs will be faster because the store
822 that is created for test purposes will already have various things in
825 It is also possible to run a subset of the tests by defining the
826 @code{TESTS} makefile variable as in this example:
829 make check TESTS="tests/store.scm tests/cpio.scm"
832 By default, tests results are displayed at a file level. In order to
833 see the details of every individual test cases, it is possible to define
834 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
837 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
840 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
841 @file{test-suite.log} file. Please specify the Guix version being used
842 as well as version numbers of the dependencies (@pxref{Requirements}) in
845 Guix also comes with a whole-system test suite that tests complete
846 Guix System instances. It can only run on systems where
847 Guix is already installed, using:
854 or, again, by defining @code{TESTS} to select a subset of tests to run:
857 make check-system TESTS="basic mcron"
860 These system tests are defined in the @code{(gnu tests @dots{})}
861 modules. They work by running the operating systems under test with
862 lightweight instrumentation in a virtual machine (VM). They can be
863 computationally intensive or rather cheap, depending on whether
864 substitutes are available for their dependencies (@pxref{Substitutes}).
865 Some of them require a lot of storage space to hold VM images.
867 Again in case of test failures, please send @email{bug-guix@@gnu.org}
870 @node Setting Up the Daemon
871 @section Setting Up the Daemon
874 Operations such as building a package or running the garbage collector
875 are all performed by a specialized process, the @dfn{build daemon}, on
876 behalf of clients. Only the daemon may access the store and its
877 associated database. Thus, any operation that manipulates the store
878 goes through the daemon. For instance, command-line tools such as
879 @command{guix package} and @command{guix build} communicate with the
880 daemon (@i{via} remote procedure calls) to instruct it what to do.
882 The following sections explain how to prepare the build daemon's
883 environment. See also @ref{Substitutes}, for information on how to allow
884 the daemon to download pre-built binaries.
887 * Build Environment Setup:: Preparing the isolated build environment.
888 * Daemon Offload Setup:: Offloading builds to remote machines.
889 * SELinux Support:: Using an SELinux policy for the daemon.
892 @node Build Environment Setup
893 @subsection Build Environment Setup
895 @cindex build environment
896 In a standard multi-user setup, Guix and its daemon---the
897 @command{guix-daemon} program---are installed by the system
898 administrator; @file{/gnu/store} is owned by @code{root} and
899 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
900 Guix tools to build packages or otherwise access the store, and the
901 daemon will do it on their behalf, ensuring that the store is kept in a
902 consistent state, and allowing built packages to be shared among users.
905 When @command{guix-daemon} runs as @code{root}, you may not want package
906 build processes themselves to run as @code{root} too, for obvious
907 security reasons. To avoid that, a special pool of @dfn{build users}
908 should be created for use by build processes started by the daemon.
909 These build users need not have a shell and a home directory: they will
910 just be used when the daemon drops @code{root} privileges in build
911 processes. Having several such users allows the daemon to launch
912 distinct build processes under separate UIDs, which guarantees that they
913 do not interfere with each other---an essential feature since builds are
914 regarded as pure functions (@pxref{Introduction}).
916 On a GNU/Linux system, a build user pool may be created like this (using
917 Bash syntax and the @code{shadow} commands):
919 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
920 @c for why `-G' is needed.
922 # groupadd --system guixbuild
923 # for i in `seq -w 1 10`;
925 useradd -g guixbuild -G guixbuild \
926 -d /var/empty -s `which nologin` \
927 -c "Guix build user $i" --system \
933 The number of build users determines how many build jobs may run in
934 parallel, as specified by the @option{--max-jobs} option
935 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
936 @command{guix system vm} and related commands, you may need to add the
937 build users to the @code{kvm} group so they can access @file{/dev/kvm},
938 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
939 (@pxref{Invoking guix system}).
941 The @code{guix-daemon} program may then be run as @code{root} with the
942 following command@footnote{If your machine uses the systemd init system,
943 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
944 file in @file{/etc/systemd/system} will ensure that
945 @command{guix-daemon} is automatically started. Similarly, if your
946 machine uses the Upstart init system, drop the
947 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
948 file in @file{/etc/init}.}:
951 # guix-daemon --build-users-group=guixbuild
956 This way, the daemon starts build processes in a chroot, under one of
957 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
958 environment contains nothing but:
960 @c Keep this list in sync with libstore/build.cc! -----------------------
963 a minimal @code{/dev} directory, created mostly independently from the
964 host @code{/dev}@footnote{``Mostly'', because while the set of files
965 that appear in the chroot's @code{/dev} is fixed, most of these files
966 can only be created if the host has them.};
969 the @code{/proc} directory; it only shows the processes of the container
970 since a separate PID name space is used;
973 @file{/etc/passwd} with an entry for the current user and an entry for
977 @file{/etc/group} with an entry for the user's group;
980 @file{/etc/hosts} with an entry that maps @code{localhost} to
984 a writable @file{/tmp} directory.
987 You can influence the directory where the daemon stores build trees
988 @i{via} the @code{TMPDIR} environment variable. However, the build tree
989 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
990 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
991 This way, the value of @code{TMPDIR} does not leak inside build
992 environments, which avoids discrepancies in cases where build processes
993 capture the name of their build tree.
996 The daemon also honors the @code{http_proxy} environment variable for
997 HTTP downloads it performs, be it for fixed-output derivations
998 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1000 If you are installing Guix as an unprivileged user, it is still possible
1001 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1002 However, build processes will not be isolated from one another, and not
1003 from the rest of the system. Thus, build processes may interfere with
1004 each other, and may access programs, libraries, and other files
1005 available on the system---making it much harder to view them as
1006 @emph{pure} functions.
1009 @node Daemon Offload Setup
1010 @subsection Using the Offload Facility
1014 When desired, the build daemon can @dfn{offload} derivation builds to
1015 other machines running Guix, using the @code{offload} @dfn{build
1016 hook}@footnote{This feature is available only when
1017 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1018 present.}. When that
1019 feature is enabled, a list of user-specified build machines is read from
1020 @file{/etc/guix/machines.scm}; every time a build is requested, for
1021 instance via @code{guix build}, the daemon attempts to offload it to one
1022 of the machines that satisfy the constraints of the derivation, in
1023 particular its system type---e.g., @file{x86_64-linux}. Missing
1024 prerequisites for the build are copied over SSH to the target machine,
1025 which then proceeds with the build; upon success the output(s) of the
1026 build are copied back to the initial machine.
1028 The @file{/etc/guix/machines.scm} file typically looks like this:
1031 (list (build-machine
1032 (name "eightysix.example.org")
1033 (system "x86_64-linux")
1034 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1036 (speed 2.)) ;incredibly fast!
1039 (name "meeps.example.org")
1040 (system "mips64el-linux")
1041 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1044 (string-append (getenv "HOME")
1045 "/.ssh/identity-for-guix"))))
1049 In the example above we specify a list of two build machines, one for
1050 the @code{x86_64} architecture and one for the @code{mips64el}
1053 In fact, this file is---not surprisingly!---a Scheme file that is
1054 evaluated when the @code{offload} hook is started. Its return value
1055 must be a list of @code{build-machine} objects. While this example
1056 shows a fixed list of build machines, one could imagine, say, using
1057 DNS-SD to return a list of potential build machines discovered in the
1058 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1059 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1062 @deftp {Data Type} build-machine
1063 This data type represents build machines to which the daemon may offload
1064 builds. The important fields are:
1069 The host name of the remote machine.
1072 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1075 The user account to use when connecting to the remote machine over SSH.
1076 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1077 allow non-interactive logins.
1080 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1081 This is used to authenticate the machine when we connect to it. It is a
1082 long string that looks like this:
1085 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1088 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1089 key can be found in a file such as
1090 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1092 If the machine is running the SSH daemon of GNU@tie{}lsh,
1093 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1094 similar file. It can be converted to the OpenSSH format using
1095 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1098 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1099 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1104 A number of optional fields may be specified:
1108 @item @code{port} (default: @code{22})
1109 Port number of SSH server on the machine.
1111 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1112 The SSH private key file to use when connecting to the machine, in
1113 OpenSSH format. This key must not be protected with a passphrase.
1115 Note that the default value is the private key @emph{of the root
1116 account}. Make sure it exists if you use the default.
1118 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1119 @itemx @code{compression-level} (default: @code{3})
1120 The SSH-level compression methods and compression level requested.
1122 Note that offloading relies on SSH compression to reduce bandwidth usage
1123 when transferring files to and from build machines.
1125 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1126 File name of the Unix-domain socket @command{guix-daemon} is listening
1129 @item @code{parallel-builds} (default: @code{1})
1130 The number of builds that may run in parallel on the machine.
1132 @item @code{speed} (default: @code{1.0})
1133 A ``relative speed factor''. The offload scheduler will tend to prefer
1134 machines with a higher speed factor.
1136 @item @code{features} (default: @code{'()})
1137 A list of strings denoting specific features supported by the machine.
1138 An example is @code{"kvm"} for machines that have the KVM Linux modules
1139 and corresponding hardware support. Derivations can request features by
1140 name, and they will be scheduled on matching build machines.
1145 The @command{guix} command must be in the search path on the build
1146 machines. You can check whether this is the case by running:
1149 ssh build-machine guix repl --version
1152 There is one last thing to do once @file{machines.scm} is in place. As
1153 explained above, when offloading, files are transferred back and forth
1154 between the machine stores. For this to work, you first need to
1155 generate a key pair on each machine to allow the daemon to export signed
1156 archives of files from the store (@pxref{Invoking guix archive}):
1159 # guix archive --generate-key
1163 Each build machine must authorize the key of the master machine so that
1164 it accepts store items it receives from the master:
1167 # guix archive --authorize < master-public-key.txt
1171 Likewise, the master machine must authorize the key of each build machine.
1173 All the fuss with keys is here to express pairwise mutual trust
1174 relations between the master and the build machines. Concretely, when
1175 the master receives files from a build machine (and @i{vice versa}), its
1176 build daemon can make sure they are genuine, have not been tampered
1177 with, and that they are signed by an authorized key.
1179 @cindex offload test
1180 To test whether your setup is operational, run this command on the
1187 This will attempt to connect to each of the build machines specified in
1188 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1189 available on each machine, attempt to export to the machine and import
1190 from it, and report any error in the process.
1192 If you want to test a different machine file, just specify it on the
1196 # guix offload test machines-qualif.scm
1199 Last, you can test the subset of the machines whose name matches a
1200 regular expression like this:
1203 # guix offload test machines.scm '\.gnu\.org$'
1206 @cindex offload status
1207 To display the current load of all build hosts, run this command on the
1211 # guix offload status
1215 @node SELinux Support
1216 @subsection SELinux Support
1218 @cindex SELinux, daemon policy
1219 @cindex mandatory access control, SELinux
1220 @cindex security, guix-daemon
1221 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1222 can be installed on a system where SELinux is enabled, in order to label
1223 Guix files and to specify the expected behavior of the daemon. Since
1224 Guix System does not provide an SELinux base policy, the daemon policy cannot
1225 be used on Guix System.
1227 @subsubsection Installing the SELinux policy
1228 @cindex SELinux, policy installation
1229 To install the policy run this command as root:
1232 semodule -i etc/guix-daemon.cil
1235 Then relabel the file system with @code{restorecon} or by a different
1236 mechanism provided by your system.
1238 Once the policy is installed, the file system has been relabeled, and
1239 the daemon has been restarted, it should be running in the
1240 @code{guix_daemon_t} context. You can confirm this with the following
1244 ps -Zax | grep guix-daemon
1247 Monitor the SELinux log files as you run a command like @code{guix build
1248 hello} to convince yourself that SELinux permits all necessary
1251 @subsubsection Limitations
1252 @cindex SELinux, limitations
1254 This policy is not perfect. Here is a list of limitations or quirks
1255 that should be considered when deploying the provided SELinux policy for
1260 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1261 operations involve contexts that have anything to do with
1262 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1263 but it would be preferrable to define socket rules for only this label.
1266 @code{guix gc} cannot access arbitrary links to profiles. By design,
1267 the file label of the destination of a symlink is independent of the
1268 file label of the link itself. Although all profiles under
1269 $localstatedir are labelled, the links to these profiles inherit the
1270 label of the directory they are in. For links in the user’s home
1271 directory this will be @code{user_home_t}. But for links from the root
1272 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1273 directory, etc, this won’t work. @code{guix gc} would be prevented from
1274 reading and following these links.
1277 The daemon’s feature to listen for TCP connections might no longer work.
1278 This might require extra rules, because SELinux treats network sockets
1279 differently from files.
1282 Currently all files with a name matching the regular expression
1283 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1284 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1285 that name in any profile would be permitted to run in the
1286 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1287 build a package that provides this executable and convince a user to
1288 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1289 At that point SELinux could not prevent it from accessing files that are
1290 allowed for processes in that domain.
1292 We could generate a much more restrictive policy at installation time,
1293 so that only the @emph{exact} file name of the currently installed
1294 @code{guix-daemon} executable would be labelled with
1295 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1296 The downside is that root would have to install or upgrade the policy at
1297 installation time whenever the Guix package that provides the
1298 effectively running @code{guix-daemon} executable is upgraded.
1301 @node Invoking guix-daemon
1302 @section Invoking @command{guix-daemon}
1304 The @command{guix-daemon} program implements all the functionality to
1305 access the store. This includes launching build processes, running the
1306 garbage collector, querying the availability of a build result, etc. It
1307 is normally run as @code{root} like this:
1310 # guix-daemon --build-users-group=guixbuild
1314 For details on how to set it up, @pxref{Setting Up the Daemon}.
1317 @cindex container, build environment
1318 @cindex build environment
1319 @cindex reproducible builds
1320 By default, @command{guix-daemon} launches build processes under
1321 different UIDs, taken from the build group specified with
1322 @code{--build-users-group}. In addition, each build process is run in a
1323 chroot environment that only contains the subset of the store that the
1324 build process depends on, as specified by its derivation
1325 (@pxref{Programming Interface, derivation}), plus a set of specific
1326 system directories. By default, the latter contains @file{/dev} and
1327 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1328 @dfn{container}: in addition to having its own file system tree, it has
1329 a separate mount name space, its own PID name space, network name space,
1330 etc. This helps achieve reproducible builds (@pxref{Features}).
1332 When the daemon performs a build on behalf of the user, it creates a
1333 build directory under @file{/tmp} or under the directory specified by
1334 its @code{TMPDIR} environment variable. This directory is shared with
1335 the container for the duration of the build, though within the container,
1336 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1338 The build directory is automatically deleted upon completion, unless the
1339 build failed and the client specified @option{--keep-failed}
1340 (@pxref{Invoking guix build, @option{--keep-failed}}).
1342 The daemon listens for connections and spawns one sub-process for each session
1343 started by a client (one of the @command{guix} sub-commands.) The
1344 @command{guix processes} command allows you to get an overview of the activity
1345 on your system by viewing each of the active sessions and clients.
1346 @xref{Invoking guix processes}, for more information.
1348 The following command-line options are supported:
1351 @item --build-users-group=@var{group}
1352 Take users from @var{group} to run build processes (@pxref{Setting Up
1353 the Daemon, build users}).
1355 @item --no-substitutes
1357 Do not use substitutes for build products. That is, always build things
1358 locally instead of allowing downloads of pre-built binaries
1359 (@pxref{Substitutes}).
1361 When the daemon runs with @code{--no-substitutes}, clients can still
1362 explicitly enable substitution @i{via} the @code{set-build-options}
1363 remote procedure call (@pxref{The Store}).
1365 @item --substitute-urls=@var{urls}
1366 @anchor{daemon-substitute-urls}
1367 Consider @var{urls} the default whitespace-separated list of substitute
1368 source URLs. When this option is omitted,
1369 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1371 This means that substitutes may be downloaded from @var{urls}, as long
1372 as they are signed by a trusted signature (@pxref{Substitutes}).
1375 @item --no-build-hook
1376 Do not use the @dfn{build hook}.
1378 The build hook is a helper program that the daemon can start and to
1379 which it submits build requests. This mechanism is used to offload
1380 builds to other machines (@pxref{Daemon Offload Setup}).
1382 @item --cache-failures
1383 Cache build failures. By default, only successful builds are cached.
1385 When this option is used, @command{guix gc --list-failures} can be used
1386 to query the set of store items marked as failed; @command{guix gc
1387 --clear-failures} removes store items from the set of cached failures.
1388 @xref{Invoking guix gc}.
1390 @item --cores=@var{n}
1392 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1395 The default value is @code{0}, but it may be overridden by clients, such
1396 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1399 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1400 in the build process, which can then use it to exploit internal
1401 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1403 @item --max-jobs=@var{n}
1405 Allow at most @var{n} build jobs in parallel. The default value is
1406 @code{1}. Setting it to @code{0} means that no builds will be performed
1407 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1408 Setup}), or simply fail.
1410 @item --max-silent-time=@var{seconds}
1411 When the build or substitution process remains silent for more than
1412 @var{seconds}, terminate it and report a build failure.
1414 The default value is @code{0}, which disables the timeout.
1416 The value specified here can be overridden by clients (@pxref{Common
1417 Build Options, @code{--max-silent-time}}).
1419 @item --timeout=@var{seconds}
1420 Likewise, when the build or substitution process lasts for more than
1421 @var{seconds}, terminate it and report a build failure.
1423 The default value is @code{0}, which disables the timeout.
1425 The value specified here can be overridden by clients (@pxref{Common
1426 Build Options, @code{--timeout}}).
1428 @item --rounds=@var{N}
1429 Build each derivation @var{n} times in a row, and raise an error if
1430 consecutive build results are not bit-for-bit identical. Note that this
1431 setting can be overridden by clients such as @command{guix build}
1432 (@pxref{Invoking guix build}).
1434 When used in conjunction with @option{--keep-failed}, the differing
1435 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1436 This makes it easy to look for differences between the two results.
1439 Produce debugging output.
1441 This is useful to debug daemon start-up issues, but then it may be
1442 overridden by clients, for example the @code{--verbosity} option of
1443 @command{guix build} (@pxref{Invoking guix build}).
1445 @item --chroot-directory=@var{dir}
1446 Add @var{dir} to the build chroot.
1448 Doing this may change the result of build processes---for instance if
1449 they use optional dependencies found in @var{dir} when it is available,
1450 and not otherwise. For that reason, it is not recommended to do so.
1451 Instead, make sure that each derivation declares all the inputs that it
1454 @item --disable-chroot
1455 Disable chroot builds.
1457 Using this option is not recommended since, again, it would allow build
1458 processes to gain access to undeclared dependencies. It is necessary,
1459 though, when @command{guix-daemon} is running under an unprivileged user
1462 @item --log-compression=@var{type}
1463 Compress build logs according to @var{type}, one of @code{gzip},
1464 @code{bzip2}, or @code{none}.
1466 Unless @code{--lose-logs} is used, all the build logs are kept in the
1467 @var{localstatedir}. To save space, the daemon automatically compresses
1468 them with bzip2 by default.
1470 @item --disable-deduplication
1471 @cindex deduplication
1472 Disable automatic file ``deduplication'' in the store.
1474 By default, files added to the store are automatically ``deduplicated'':
1475 if a newly added file is identical to another one found in the store,
1476 the daemon makes the new file a hard link to the other file. This can
1477 noticeably reduce disk usage, at the expense of slightly increased
1478 input/output load at the end of a build process. This option disables
1481 @item --gc-keep-outputs[=yes|no]
1482 Tell whether the garbage collector (GC) must keep outputs of live
1486 @cindex garbage collector roots
1487 When set to ``yes'', the GC will keep the outputs of any live derivation
1488 available in the store---the @code{.drv} files. The default is ``no'',
1489 meaning that derivation outputs are kept only if they are reachable from a GC
1490 root. @xref{Invoking guix gc}, for more on GC roots.
1492 @item --gc-keep-derivations[=yes|no]
1493 Tell whether the garbage collector (GC) must keep derivations
1494 corresponding to live outputs.
1496 When set to ``yes'', as is the case by default, the GC keeps
1497 derivations---i.e., @code{.drv} files---as long as at least one of their
1498 outputs is live. This allows users to keep track of the origins of
1499 items in their store. Setting it to ``no'' saves a bit of disk space.
1501 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1502 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1503 ``yes'' causes liveness to flow from derivations to outputs. When both are
1504 set to ``yes'', the effect is to keep all the build prerequisites (the
1505 sources, compiler, libraries, and other build-time tools) of live objects in
1506 the store, regardless of whether these prerequisites are reachable from a GC
1507 root. This is convenient for developers since it saves rebuilds or downloads.
1509 @item --impersonate-linux-2.6
1510 On Linux-based systems, impersonate Linux 2.6. This means that the
1511 kernel's @code{uname} system call will report 2.6 as the release number.
1513 This might be helpful to build programs that (usually wrongfully) depend
1514 on the kernel version number.
1517 Do not keep build logs. By default they are kept under
1518 @code{@var{localstatedir}/guix/log}.
1520 @item --system=@var{system}
1521 Assume @var{system} as the current system type. By default it is the
1522 architecture/kernel pair found at configure time, such as
1523 @code{x86_64-linux}.
1525 @item --listen=@var{endpoint}
1526 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1527 as the file name of a Unix-domain socket if it starts with
1528 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1529 host name or host name and port to listen to. Here are a few examples:
1532 @item --listen=/gnu/var/daemon
1533 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1534 creating it if needed.
1536 @item --listen=localhost
1537 @cindex daemon, remote access
1538 @cindex remote access to the daemon
1539 @cindex daemon, cluster setup
1540 @cindex clusters, daemon setup
1541 Listen for TCP connections on the network interface corresponding to
1542 @code{localhost}, on port 44146.
1544 @item --listen=128.0.0.42:1234
1545 Listen for TCP connections on the network interface corresponding to
1546 @code{128.0.0.42}, on port 1234.
1549 This option can be repeated multiple times, in which case
1550 @command{guix-daemon} accepts connections on all the specified
1551 endpoints. Users can tell client commands what endpoint to connect to
1552 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1553 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1556 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1557 @code{--listen=@var{host}} is suitable on local networks, such as
1558 clusters, where only trusted nodes may connect to the build daemon. In
1559 other cases where remote access to the daemon is needed, we recommend
1560 using Unix-domain sockets along with SSH.
1563 When @code{--listen} is omitted, @command{guix-daemon} listens for
1564 connections on the Unix-domain socket located at
1565 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1569 @node Application Setup
1570 @section Application Setup
1572 @cindex foreign distro
1573 When using Guix on top of GNU/Linux distribution other than Guix System---a
1574 so-called @dfn{foreign distro}---a few additional steps are needed to
1575 get everything in place. Here are some of them.
1579 @anchor{locales-and-locpath}
1580 @cindex locales, when not on Guix System
1582 @vindex GUIX_LOCPATH
1583 Packages installed @i{via} Guix will not use the locale data of the
1584 host system. Instead, you must first install one of the locale packages
1585 available with Guix and then define the @code{GUIX_LOCPATH} environment
1589 $ guix install glibc-locales
1590 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1593 Note that the @code{glibc-locales} package contains data for all the
1594 locales supported by the GNU@tie{}libc and weighs in at around
1595 110@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1596 limited to a few UTF-8 locales.
1598 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1599 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1600 Manual}). There are two important differences though:
1604 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1605 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1606 to make sure the programs of the foreign distro will not end up loading
1607 incompatible locale data.
1610 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1611 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1612 should your Guix profile contain a mixture of programs linked against
1613 different libc version, each libc version will only try to load locale
1614 data in the right format.
1617 This is important because the locale data format used by different libc
1618 versions may be incompatible.
1620 @subsection Name Service Switch
1622 @cindex name service switch, glibc
1623 @cindex NSS (name service switch), glibc
1624 @cindex nscd (name service caching daemon)
1625 @cindex name service caching daemon (nscd)
1626 When using Guix on a foreign distro, we @emph{strongly recommend} that
1627 the system run the GNU C library's @dfn{name service cache daemon},
1628 @command{nscd}, which should be listening on the
1629 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1630 installed with Guix may fail to look up host names or user accounts, or
1631 may even crash. The next paragraphs explain why.
1633 @cindex @file{nsswitch.conf}
1634 The GNU C library implements a @dfn{name service switch} (NSS), which is
1635 an extensible mechanism for ``name lookups'' in general: host name
1636 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1637 The GNU C Library Reference Manual}).
1639 @cindex Network information service (NIS)
1640 @cindex NIS (Network information service)
1641 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1642 lookup implementations: for example, the @code{nss-mdns} plugin allow
1643 resolution of @code{.local} host names, the @code{nis} plugin allows
1644 user account lookup using the Network information service (NIS), and so
1645 on. These extra ``lookup services'' are configured system-wide in
1646 @file{/etc/nsswitch.conf}, and all the programs running on the system
1647 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1650 When they perform a name lookup---for instance by calling the
1651 @code{getaddrinfo} function in C---applications first try to connect to
1652 the nscd; on success, nscd performs name lookups on their behalf. If
1653 the nscd is not running, then they perform the name lookup by
1654 themselves, by loading the name lookup services into their own address
1655 space and running it. These name lookup services---the
1656 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1657 the host system's C library, rather than from the C library the
1658 application is linked against (the C library coming from Guix).
1660 And this is where the problem is: if your application is linked against
1661 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1662 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1663 likely crash or have its name lookups fail unexpectedly.
1665 Running @command{nscd} on the system, among other advantages, eliminates
1666 this binary incompatibility problem because those @code{libnss_*.so}
1667 files are loaded in the @command{nscd} process, not in applications
1670 @subsection X11 Fonts
1673 The majority of graphical applications use Fontconfig to locate and
1674 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1675 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1676 by default. Thus, to allow graphical applications installed with Guix
1677 to display fonts, you have to install fonts with Guix as well.
1678 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1679 @code{font-gnu-freefont-ttf}.
1681 To display text written in Chinese languages, Japanese, or Korean in
1682 graphical applications, consider installing
1683 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1684 has multiple outputs, one per language family (@pxref{Packages with
1685 Multiple Outputs}). For instance, the following command installs fonts
1686 for Chinese languages:
1689 guix install font-adobe-source-han-sans:cn
1692 @cindex @code{xterm}
1693 Older programs such as @command{xterm} do not use Fontconfig and instead
1694 rely on server-side font rendering. Such programs require to specify a
1695 full name of a font using XLFD (X Logical Font Description), like this:
1698 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1701 To be able to use such full names for the TrueType fonts installed in
1702 your Guix profile, you need to extend the font path of the X server:
1704 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1705 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1707 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1710 @cindex @code{xlsfonts}
1711 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1712 to make sure your TrueType fonts are listed there.
1714 @cindex @code{fc-cache}
1716 After installing fonts you may have to refresh the font cache to use
1717 them in applications. The same applies when applications installed via
1718 Guix do not seem to find fonts. To force rebuilding of the font cache
1719 run @code{fc-cache -f}. The @code{fc-cache} command is provided by the
1720 @code{fontconfig} package.
1722 @subsection X.509 Certificates
1724 @cindex @code{nss-certs}
1725 The @code{nss-certs} package provides X.509 certificates, which allow
1726 programs to authenticate Web servers accessed over HTTPS.
1728 When using Guix on a foreign distro, you can install this package and
1729 define the relevant environment variables so that packages know where to
1730 look for certificates. @xref{X.509 Certificates}, for detailed
1733 @subsection Emacs Packages
1735 @cindex @code{emacs}
1736 When you install Emacs packages with Guix, the elisp files may be placed
1737 either in @file{$HOME/.guix-profile/share/emacs/site-lisp/} or in
1739 @file{$HOME/.guix-profile/share/emacs/site-lisp/guix.d/}. The latter
1740 directory exists because potentially there may exist thousands of Emacs
1741 packages and storing all their files in a single directory may not be
1742 reliable (because of name conflicts). So we think using a separate
1743 directory for each package is a good idea. It is very similar to how
1744 the Emacs package system organizes the file structure (@pxref{Package
1745 Files,,, emacs, The GNU Emacs Manual}).
1747 By default, Emacs (installed with Guix) ``knows'' where these packages
1748 are placed, so you do not need to perform any configuration. If, for
1749 some reason, you want to avoid auto-loading Emacs packages installed
1750 with Guix, you can do so by running Emacs with @code{--no-site-file}
1751 option (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1753 @subsection The GCC toolchain
1758 Guix offers individual compiler packages such as @code{gcc} but if you
1759 are in need of a complete toolchain for compiling and linking source
1760 code what you really want is the @code{gcc-toolchain} package. This
1761 package provides a complete GCC toolchain for C/C++ development,
1762 including GCC itself, the GNU C Library (headers and binaries, plus
1763 debugging symbols in the @code{debug} output), Binutils, and a linker
1766 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
1767 passed to the linker, add corresponding @code{-rpath} arguments, and
1768 invoke the actual linker with this new set of arguments. You can instruct the
1769 wrapper to refuse to link against libraries not in the store by setting the
1770 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
1774 @c *********************************************************************
1775 @node System Installation
1776 @chapter System Installation
1778 @cindex installing Guix System
1779 @cindex Guix System, installation
1780 This section explains how to install Guix System
1781 on a machine. Guix, as a package manager, can
1782 also be installed on top of a running GNU/Linux system,
1783 @pxref{Installation}.
1787 @c This paragraph is for people reading this from tty2 of the
1788 @c installation image.
1789 You are reading this documentation with an Info reader. For details on
1790 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1791 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1792 Info}. Hit @kbd{l} afterwards to come back here.
1794 Alternately, run @command{info info} in another tty to keep the manual
1800 * Limitations:: What you can expect.
1801 * Hardware Considerations:: Supported hardware.
1802 * USB Stick and DVD Installation:: Preparing the installation medium.
1803 * Preparing for Installation:: Networking, partitioning, etc.
1804 * Guided Graphical Installation:: Easy graphical installation.
1805 * Manual Installation:: Manual installation for wizards.
1806 * After System Installation:: When installation succeeded.
1807 * Installing Guix in a VM:: Guix System playground.
1808 * Building the Installation Image:: How this comes to be.
1812 @section Limitations
1814 We consider Guix System to be ready for a wide range of ``desktop'' and server
1815 use cases. The reliability guarantees it provides---transactional upgrades
1816 and rollbacks, reproducibility---make it a solid foundation.
1818 Nevertheless, before you proceed with the installation, be aware of the
1819 following noteworthy limitations applicable to version @value{VERSION}:
1823 Support for the Logical Volume Manager (LVM) is missing.
1826 More and more system services are provided (@pxref{Services}), but some
1830 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1831 as well as a number of X11 window managers. However, KDE is currently
1835 More than a disclaimer, this is an invitation to report issues (and success
1836 stories!), and to join us in improving it. @xref{Contributing}, for more
1840 @node Hardware Considerations
1841 @section Hardware Considerations
1843 @cindex hardware support on Guix System
1844 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1845 builds around the kernel Linux-libre, which means that only hardware for
1846 which free software drivers and firmware exist is supported. Nowadays,
1847 a wide range of off-the-shelf hardware is supported on
1848 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1849 Ethernet controllers. Unfortunately, there are still areas where
1850 hardware vendors deny users control over their own computing, and such
1851 hardware is not supported on Guix System.
1853 @cindex WiFi, hardware support
1854 One of the main areas where free drivers or firmware are lacking is WiFi
1855 devices. WiFi devices known to work include those using Atheros chips
1856 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1857 driver, and those using Broadcom/AirForce chips (BCM43xx with
1858 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1859 Linux-libre driver. Free firmware exists for both and is available
1860 out-of-the-box on Guix System, as part of @code{%base-firmware}
1861 (@pxref{operating-system Reference, @code{firmware}}).
1863 @cindex RYF, Respects Your Freedom
1864 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1865 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1866 certification program for hardware products that respect your freedom
1867 and your privacy and ensure that you have control over your device. We
1868 encourage you to check the list of RYF-certified devices.
1870 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1871 web site. It contains a catalog of hardware devices with information
1872 about their support in GNU/Linux.
1875 @node USB Stick and DVD Installation
1876 @section USB Stick and DVD Installation
1878 An ISO-9660 installation image that can be written to a USB stick or
1879 burnt to a DVD can be downloaded from
1880 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1881 where @var{system} is one of:
1885 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1888 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1891 @c start duplication of authentication part from ``Binary Installation''
1892 Make sure to download the associated @file{.sig} file and to verify the
1893 authenticity of the image against it, along these lines:
1896 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1897 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1900 If that command fails because you do not have the required public key,
1901 then run this command to import it:
1904 $ gpg --keyserver @value{KEY-SERVER} \
1905 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
1909 and rerun the @code{gpg --verify} command.
1912 This image contains the tools necessary for an installation.
1913 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1915 @unnumberedsubsec Copying to a USB Stick
1917 To copy the image to a USB stick, follow these steps:
1921 Decompress the image using the @command{xz} command:
1924 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1928 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1929 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1930 copy the image with:
1933 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1937 Access to @file{/dev/sdX} usually requires root privileges.
1940 @unnumberedsubsec Burning on a DVD
1942 To copy the image to a DVD, follow these steps:
1946 Decompress the image using the @command{xz} command:
1949 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1953 Insert a blank DVD into your machine, and determine
1954 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
1955 copy the image with:
1958 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
1961 Access to @file{/dev/srX} usually requires root privileges.
1964 @unnumberedsubsec Booting
1966 Once this is done, you should be able to reboot the system and boot from
1967 the USB stick or DVD. The latter usually requires you to get in the
1968 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
1970 @xref{Installing Guix in a VM}, if, instead, you would like to install
1971 Guix System in a virtual machine (VM).
1974 @node Preparing for Installation
1975 @section Preparing for Installation
1977 Once you have booted, you can use the guided graphical installer, which makes
1978 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
1979 if you are already familiar with GNU/Linux and if you want more control than
1980 what the graphical installer provides, you can choose the ``manual''
1981 installation process (@pxref{Manual Installation}).
1983 The graphical installer is available on TTY1. You can obtain root shells on
1984 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
1985 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
1986 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
1987 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
1988 which allows you to select text with the left mouse button and to paste it
1989 with the middle button.
1992 Installation requires access to the Internet so that any missing
1993 dependencies of your system configuration can be downloaded. See the
1994 ``Networking'' section below.
1997 @node Guided Graphical Installation
1998 @section Guided Graphical Installation
2000 The graphical installer is a text-based user interface. It will guide you,
2001 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2003 The first dialog boxes allow you to set up the system as you use it during the
2004 installation: you can choose the language, keyboard layout, and set up
2005 networking, which will be used during the installation. The image below shows
2006 the networking dialog.
2008 @image{images/installer-network,5in,, networking setup with the graphical installer}
2010 Later steps allow you to partition your hard disk, as shown in the image
2011 below, to choose whether or not to use encrypted file systems, to enter the
2012 host name and root password, and to create an additional account, among other
2015 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2017 Note that, at any time, the installer allows you to exit the current
2018 installation step and resume at a previous step, as show in the image below.
2020 @image{images/installer-resume,5in,, resuming the installation process}
2022 Once you're done, the installer produces an operating system configuration and
2023 displays it (@pxref{Using the Configuration System}). At that point you can
2024 hit ``OK'' and installation will proceed. On success, you can reboot into the
2025 new system and enjoy. @xref{After System Installation}, for what's next!
2028 @node Manual Installation
2029 @section Manual Installation
2031 This section describes how you would ``manually'' install GNU@tie{}Guix System
2032 on your machine. This option requires familiarity with GNU/Linux, with the
2033 shell, and with common administration tools. If you think this is not for
2034 you, consider using the guided graphical installer (@pxref{Guided Graphical
2037 The installation system provides root shells on TTYs 3 to 6; press
2038 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2039 many common tools needed to install the system. But it is also a full-blown
2040 Guix System, which means that you can install additional packages, should you
2041 need it, using @command{guix package} (@pxref{Invoking guix package}).
2044 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2045 * Proceeding with the Installation:: Installing.
2048 @node Keyboard Layout and Networking and Partitioning
2049 @subsection Keyboard Layout, Networking, and Partitioning
2051 Before you can install the system, you may want to adjust the keyboard layout,
2052 set up networking, and partition your target hard disk. This section will
2053 guide you through this.
2055 @subsubsection Keyboard Layout
2057 @cindex keyboard layout
2058 The installation image uses the US qwerty keyboard layout. If you want
2059 to change it, you can use the @command{loadkeys} command. For example,
2060 the following command selects the Dvorak keyboard layout:
2066 See the files under @file{/run/current-system/profile/share/keymaps} for
2067 a list of available keyboard layouts. Run @command{man loadkeys} for
2070 @subsubsection Networking
2072 Run the following command to see what your network interfaces are called:
2079 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2085 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2086 Wired interfaces have a name starting with @samp{e}; for example, the
2087 interface corresponding to the first on-board Ethernet controller is
2088 called @samp{eno1}. Wireless interfaces have a name starting with
2089 @samp{w}, like @samp{w1p2s0}.
2092 @item Wired connection
2093 To configure a wired network run the following command, substituting
2094 @var{interface} with the name of the wired interface you want to use.
2097 ifconfig @var{interface} up
2100 @item Wireless connection
2103 To configure wireless networking, you can create a configuration file
2104 for the @command{wpa_supplicant} configuration tool (its location is not
2105 important) using one of the available text editors such as
2109 nano wpa_supplicant.conf
2112 As an example, the following stanza can go to this file and will work
2113 for many wireless networks, provided you give the actual SSID and
2114 passphrase for the network you are connecting to:
2118 ssid="@var{my-ssid}"
2120 psk="the network's secret passphrase"
2124 Start the wireless service and run it in the background with the
2125 following command (substitute @var{interface} with the name of the
2126 network interface you want to use):
2129 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2132 Run @command{man wpa_supplicant} for more information.
2136 At this point, you need to acquire an IP address. On a network where IP
2137 addresses are automatically assigned @i{via} DHCP, you can run:
2140 dhclient -v @var{interface}
2143 Try to ping a server to see if networking is up and running:
2149 Setting up network access is almost always a requirement because the
2150 image does not contain all the software and tools that may be needed.
2152 @cindex installing over SSH
2153 If you want to, you can continue the installation remotely by starting
2157 herd start ssh-daemon
2160 Make sure to either set a password with @command{passwd}, or configure
2161 OpenSSH public key authentication before logging in.
2163 @subsubsection Disk Partitioning
2165 Unless this has already been done, the next step is to partition, and
2166 then format the target partition(s).
2168 The installation image includes several partitioning tools, including
2169 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2170 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2171 the partition layout you want:
2177 If your disk uses the GUID Partition Table (GPT) format and you plan to
2178 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2179 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2182 @cindex EFI, installation
2183 @cindex UEFI, installation
2184 @cindex ESP, EFI system partition
2185 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2186 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2187 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2190 parted /dev/sda set 1 esp on
2194 @vindex grub-bootloader
2195 @vindex grub-efi-bootloader
2196 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2197 @file{/sys/firmware/efi} exists in the installation image, then you should
2198 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2199 Otherwise you should use the BIOS-based GRUB, known as
2200 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2204 Once you are done partitioning the target hard disk drive, you have to
2205 create a file system on the relevant partition(s)@footnote{Currently
2206 Guix System only supports ext4 and btrfs file systems. In particular, code
2207 that reads file system UUIDs and labels only works for these file system
2208 types.}. For the ESP, if you have one and assuming it is
2209 @file{/dev/sda1}, run:
2212 mkfs.fat -F32 /dev/sda1
2215 Preferably, assign file systems a label so that you can easily and
2216 reliably refer to them in @code{file-system} declarations (@pxref{File
2217 Systems}). This is typically done using the @code{-L} option of
2218 @command{mkfs.ext4} and related commands. So, assuming the target root
2219 partition lives at @file{/dev/sda2}, a file system with the label
2220 @code{my-root} can be created with:
2223 mkfs.ext4 -L my-root /dev/sda2
2226 @cindex encrypted disk
2227 If you are instead planning to encrypt the root partition, you can use
2228 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2229 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2230 @code{man cryptsetup}} for more information.) Assuming you want to
2231 store the root partition on @file{/dev/sda2}, the command sequence would
2232 be along these lines:
2235 cryptsetup luksFormat /dev/sda2
2236 cryptsetup open --type luks /dev/sda2 my-partition
2237 mkfs.ext4 -L my-root /dev/mapper/my-partition
2240 Once that is done, mount the target file system under @file{/mnt}
2241 with a command like (again, assuming @code{my-root} is the label of the
2245 mount LABEL=my-root /mnt
2248 Also mount any other file systems you would like to use on the target
2249 system relative to this path. If you have opted for @file{/boot/efi} as an
2250 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2251 found by @code{guix system init} afterwards.
2253 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2254 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2255 sure to initialize them with @command{mkswap}. Assuming you have one
2256 swap partition on @file{/dev/sda3}, you would run:
2263 Alternatively, you may use a swap file. For example, assuming that in
2264 the new system you want to use the file @file{/swapfile} as a swap file,
2265 you would run@footnote{This example will work for many types of file
2266 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2267 btrfs), the required steps may be different. For details, see the
2268 manual pages for @command{mkswap} and @command{swapon}.}:
2271 # This is 10 GiB of swap space. Adjust "count" to change the size.
2272 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2273 # For security, make the file readable and writable only by root.
2274 chmod 600 /mnt/swapfile
2275 mkswap /mnt/swapfile
2276 swapon /mnt/swapfile
2279 Note that if you have encrypted the root partition and created a swap
2280 file in its file system as described above, then the encryption also
2281 protects the swap file, just like any other file in that file system.
2283 @node Proceeding with the Installation
2284 @subsection Proceeding with the Installation
2286 With the target partitions ready and the target root mounted on
2287 @file{/mnt}, we're ready to go. First, run:
2290 herd start cow-store /mnt
2293 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2294 during the installation phase are written to the target disk on @file{/mnt}
2295 rather than kept in memory. This is necessary because the first phase of
2296 the @command{guix system init} command (see below) entails downloads or
2297 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2299 Next, you have to edit a file and
2300 provide the declaration of the operating system to be installed. To
2301 that end, the installation system comes with three text editors. We
2302 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2303 supports syntax highlighting and parentheses matching; other editors
2304 include GNU Zile (an Emacs clone), and
2305 nvi (a clone of the original BSD @command{vi} editor).
2306 We strongly recommend storing that file on the target root file system, say,
2307 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2308 configuration file once you have rebooted into the newly-installed system.
2310 @xref{Using the Configuration System}, for an overview of the
2311 configuration file. The example configurations discussed in that
2312 section are available under @file{/etc/configuration} in the
2313 installation image. Thus, to get started with a system configuration
2314 providing a graphical display server (a ``desktop'' system), you can run
2315 something along these lines:
2319 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2320 # nano /mnt/etc/config.scm
2323 You should pay attention to what your configuration file contains, and
2328 Make sure the @code{bootloader-configuration} form refers to the target
2329 you want to install GRUB on. It should mention @code{grub-bootloader} if
2330 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2331 for newer UEFI systems. For legacy systems, the @code{target} field
2332 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2333 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2334 currently mounted and a @code{file-system} entry is specified in your
2338 Be sure that your file system labels match the value of their respective
2339 @code{device} fields in your @code{file-system} configuration, assuming
2340 your @code{file-system} configuration uses the @code{file-system-label}
2341 procedure in its @code{device} field.
2344 If there are encrypted or RAID partitions, make sure to add a
2345 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2348 Once you are done preparing the configuration file, the new system must
2349 be initialized (remember that the target root file system is mounted
2353 guix system init /mnt/etc/config.scm /mnt
2357 This copies all the necessary files and installs GRUB on
2358 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2359 more information, @pxref{Invoking guix system}. This command may trigger
2360 downloads or builds of missing packages, which can take some time.
2362 Once that command has completed---and hopefully succeeded!---you can run
2363 @command{reboot} and boot into the new system. The @code{root} password
2364 in the new system is initially empty; other users' passwords need to be
2365 initialized by running the @command{passwd} command as @code{root},
2366 unless your configuration specifies otherwise
2367 (@pxref{user-account-password, user account passwords}).
2368 @xref{After System Installation}, for what's next!
2371 @node After System Installation
2372 @section After System Installation
2374 Success, you've now booted into Guix System! From then on, you can update the
2375 system whenever you want by running, say:
2379 sudo guix system reconfigure /etc/config.scm
2383 This builds a new system generation with the latest packages and services
2384 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2385 your system includes the latest security updates (@pxref{Security Updates}).
2387 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2389 @cindex sudo vs. @command{guix pull}
2390 Note that @command{sudo guix} runs your user's @command{guix} command and
2391 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2392 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2395 Join us on @code{#guix} on the Freenode IRC network or on
2396 @email{guix-devel@@gnu.org} to share your experience!
2399 @node Installing Guix in a VM
2400 @section Installing Guix in a Virtual Machine
2402 @cindex virtual machine, Guix System installation
2403 @cindex virtual private server (VPS)
2404 @cindex VPS (virtual private server)
2405 If you'd like to install Guix System in a virtual machine (VM) or on a
2406 virtual private server (VPS) rather than on your beloved machine, this
2409 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2410 disk image, follow these steps:
2414 First, retrieve and decompress the Guix system installation image as
2415 described previously (@pxref{USB Stick and DVD Installation}).
2418 Create a disk image that will hold the installed system. To make a
2419 qcow2-formatted disk image, use the @command{qemu-img} command:
2422 qemu-img create -f qcow2 guixsd.img 50G
2425 The resulting file will be much smaller than 50 GB (typically less than
2426 1 MB), but it will grow as the virtualized storage device is filled up.
2429 Boot the USB installation image in an VM:
2432 qemu-system-x86_64 -m 1024 -smp 1 \
2433 -net user -net nic,model=virtio -boot menu=on \
2434 -drive file=guix-system-install-@value{VERSION}.@var{system}.iso \
2435 -drive file=guixsd.img
2438 The ordering of the drives matters.
2440 In the VM console, quickly press the @kbd{F12} key to enter the boot
2441 menu. Then press the @kbd{2} key and the @kbd{RET} key to validate your
2445 You're now root in the VM, proceed with the installation process.
2446 @xref{Preparing for Installation}, and follow the instructions.
2449 Once installation is complete, you can boot the system that's on your
2450 @file{guixsd.img} image. @xref{Running Guix in a VM}, for how to do
2453 @node Building the Installation Image
2454 @section Building the Installation Image
2456 @cindex installation image
2457 The installation image described above was built using the @command{guix
2458 system} command, specifically:
2461 guix system disk-image --file-system-type=iso9660 \
2462 gnu/system/install.scm
2465 Have a look at @file{gnu/system/install.scm} in the source tree,
2466 and see also @ref{Invoking guix system} for more information
2467 about the installation image.
2469 @section Building the Installation Image for ARM Boards
2471 Many ARM boards require a specific variant of the
2472 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2474 If you build a disk image and the bootloader is not available otherwise
2475 (on another boot drive etc), it's advisable to build an image that
2476 includes the bootloader, specifically:
2479 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2482 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2483 board, a list of possible boards will be printed.
2485 @c *********************************************************************
2486 @node Package Management
2487 @chapter Package Management
2490 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2491 remove software packages, without having to know about their build
2492 procedures or dependencies. Guix also goes beyond this obvious set of
2495 This chapter describes the main features of Guix, as well as the
2496 package management tools it provides. Along with the command-line
2497 interface described below (@pxref{Invoking guix package, @code{guix
2498 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2499 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2500 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2504 guix install emacs-guix
2508 * Features:: How Guix will make your life brighter.
2509 * Invoking guix package:: Package installation, removal, etc.
2510 * Substitutes:: Downloading pre-built binaries.
2511 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2512 * Invoking guix gc:: Running the garbage collector.
2513 * Invoking guix pull:: Fetching the latest Guix and distribution.
2514 * Channels:: Customizing the package collection.
2515 * Inferiors:: Interacting with another revision of Guix.
2516 * Invoking guix describe:: Display information about your Guix revision.
2517 * Invoking guix archive:: Exporting and importing store files.
2523 When using Guix, each package ends up in the @dfn{package store}, in its
2524 own directory---something that resembles
2525 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2527 Instead of referring to these directories, users have their own
2528 @dfn{profile}, which points to the packages that they actually want to
2529 use. These profiles are stored within each user's home directory, at
2530 @code{$HOME/.guix-profile}.
2532 For example, @code{alice} installs GCC 4.7.2. As a result,
2533 @file{/home/alice/.guix-profile/bin/gcc} points to
2534 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2535 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2536 simply continues to point to
2537 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2538 coexist on the same system without any interference.
2540 The @command{guix package} command is the central tool to manage
2541 packages (@pxref{Invoking guix package}). It operates on the per-user
2542 profiles, and can be used @emph{with normal user privileges}.
2544 @cindex transactions
2545 The command provides the obvious install, remove, and upgrade
2546 operations. Each invocation is actually a @emph{transaction}: either
2547 the specified operation succeeds, or nothing happens. Thus, if the
2548 @command{guix package} process is terminated during the transaction,
2549 or if a power outage occurs during the transaction, then the user's
2550 profile remains in its previous state, and remains usable.
2552 In addition, any package transaction may be @emph{rolled back}. So, if,
2553 for example, an upgrade installs a new version of a package that turns
2554 out to have a serious bug, users may roll back to the previous instance
2555 of their profile, which was known to work well. Similarly, the global
2556 system configuration on Guix is subject to
2557 transactional upgrades and roll-back
2558 (@pxref{Using the Configuration System}).
2560 All packages in the package store may be @emph{garbage-collected}.
2561 Guix can determine which packages are still referenced by user
2562 profiles, and remove those that are provably no longer referenced
2563 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2564 generations of their profile so that the packages they refer to can be
2567 @cindex reproducibility
2568 @cindex reproducible builds
2569 Guix takes a @dfn{purely functional} approach to package
2570 management, as described in the introduction (@pxref{Introduction}).
2571 Each @file{/gnu/store} package directory name contains a hash of all the
2572 inputs that were used to build that package---compiler, libraries, build
2573 scripts, etc. This direct correspondence allows users to make sure a
2574 given package installation matches the current state of their
2575 distribution. It also helps maximize @dfn{build reproducibility}:
2576 thanks to the isolated build environments that are used, a given build
2577 is likely to yield bit-identical files when performed on different
2578 machines (@pxref{Invoking guix-daemon, container}).
2581 This foundation allows Guix to support @dfn{transparent binary/source
2582 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2583 available from an external source---a @dfn{substitute}, Guix just
2584 downloads it and unpacks it;
2585 otherwise, it builds the package from source, locally
2586 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2587 reproducible, users do not have to trust servers that provide
2588 substitutes: they can force a local build and @emph{challenge} providers
2589 (@pxref{Invoking guix challenge}).
2591 Control over the build environment is a feature that is also useful for
2592 developers. The @command{guix environment} command allows developers of
2593 a package to quickly set up the right development environment for their
2594 package, without having to manually install the dependencies of the
2595 package into their profile (@pxref{Invoking guix environment}).
2597 @cindex replication, of software environments
2598 @cindex provenance tracking, of software artifacts
2599 All of Guix and its package definitions is version-controlled, and
2600 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2601 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2602 Guix instance on a different machine or at a later point in time, which in
2603 turn allows you to @emph{replicate complete software environments}, while
2604 retaining precise @dfn{provenance tracking} of the software.
2606 @node Invoking guix package
2607 @section Invoking @command{guix package}
2609 @cindex installing packages
2610 @cindex removing packages
2611 @cindex package installation
2612 @cindex package removal
2613 The @command{guix package} command is the tool that allows users to
2614 install, upgrade, and remove packages, as well as rolling back to
2615 previous configurations. It operates only on the user's own profile,
2616 and works with normal user privileges (@pxref{Features}). Its syntax
2620 guix package @var{options}
2623 @cindex transactions
2624 Primarily, @var{options} specifies the operations to be performed during
2625 the transaction. Upon completion, a new profile is created, but
2626 previous @dfn{generations} of the profile remain available, should the user
2629 For example, to remove @code{lua} and install @code{guile} and
2630 @code{guile-cairo} in a single transaction:
2633 guix package -r lua -i guile guile-cairo
2636 @cindex aliases, for @command{guix package}
2637 For your convenience, we also provide the following aliases:
2641 @command{guix search} is an alias for @command{guix package -s},
2643 @command{guix install} is an alias for @command{guix package -i},
2645 @command{guix remove} is an alias for @command{guix package -r},
2647 and @command{guix upgrade} is an alias for @command{guix package -u}.
2650 These aliases are less expressive than @command{guix package} and provide
2651 fewer options, so in some cases you'll probably want to use @command{guix
2654 @command{guix package} also supports a @dfn{declarative approach}
2655 whereby the user specifies the exact set of packages to be available and
2656 passes it @i{via} the @option{--manifest} option
2657 (@pxref{profile-manifest, @option{--manifest}}).
2660 For each user, a symlink to the user's default profile is automatically
2661 created in @file{$HOME/.guix-profile}. This symlink always points to the
2662 current generation of the user's default profile. Thus, users can add
2663 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2664 variable, and so on.
2665 @cindex search paths
2666 If you are not using Guix System, consider adding the
2667 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2668 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2669 shells get all the right environment variable definitions:
2672 GUIX_PROFILE="$HOME/.guix-profile" ; \
2673 source "$HOME/.guix-profile/etc/profile"
2676 In a multi-user setup, user profiles are stored in a place registered as
2677 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2678 to (@pxref{Invoking guix gc}). That directory is normally
2679 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2680 @var{localstatedir} is the value passed to @code{configure} as
2681 @code{--localstatedir}, and @var{user} is the user name. The
2682 @file{per-user} directory is created when @command{guix-daemon} is
2683 started, and the @var{user} sub-directory is created by @command{guix
2686 The @var{options} can be among the following:
2690 @item --install=@var{package} @dots{}
2691 @itemx -i @var{package} @dots{}
2692 Install the specified @var{package}s.
2694 Each @var{package} may specify either a simple package name, such as
2695 @code{guile}, or a package name followed by an at-sign and version number,
2696 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2697 case, the newest version prefixed by @code{1.8} is selected.)
2699 If no version number is specified, the
2700 newest available version will be selected. In addition, @var{package}
2701 may contain a colon, followed by the name of one of the outputs of the
2702 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2703 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2704 name (and optionally version) are searched for among the GNU
2705 distribution modules (@pxref{Package Modules}).
2707 @cindex propagated inputs
2708 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2709 that automatically get installed along with the required package
2710 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2711 @code{package} objects}, for information about propagated inputs in
2712 package definitions).
2714 @anchor{package-cmd-propagated-inputs}
2715 An example is the GNU MPC library: its C header files refer to those of
2716 the GNU MPFR library, which in turn refer to those of the GMP library.
2717 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2718 in the profile; removing MPC also removes MPFR and GMP---unless they had
2719 also been explicitly installed by the user.
2721 Besides, packages sometimes rely on the definition of environment
2722 variables for their search paths (see explanation of
2723 @code{--search-paths} below). Any missing or possibly incorrect
2724 environment variable definitions are reported here.
2726 @item --install-from-expression=@var{exp}
2728 Install the package @var{exp} evaluates to.
2730 @var{exp} must be a Scheme expression that evaluates to a
2731 @code{<package>} object. This option is notably useful to disambiguate
2732 between same-named variants of a package, with expressions such as
2733 @code{(@@ (gnu packages base) guile-final)}.
2735 Note that this option installs the first output of the specified
2736 package, which may be insufficient when needing a specific output of a
2737 multiple-output package.
2739 @item --install-from-file=@var{file}
2740 @itemx -f @var{file}
2741 Install the package that the code within @var{file} evaluates to.
2743 As an example, @var{file} might contain a definition like this
2744 (@pxref{Defining Packages}):
2747 @verbatiminclude package-hello.scm
2750 Developers may find it useful to include such a @file{guix.scm} file
2751 in the root of their project source tree that can be used to test
2752 development snapshots and create reproducible development environments
2753 (@pxref{Invoking guix environment}).
2755 @item --remove=@var{package} @dots{}
2756 @itemx -r @var{package} @dots{}
2757 Remove the specified @var{package}s.
2759 As for @code{--install}, each @var{package} may specify a version number
2760 and/or output name in addition to the package name. For instance,
2761 @code{-r glibc:debug} would remove the @code{debug} output of
2764 @item --upgrade[=@var{regexp} @dots{}]
2765 @itemx -u [@var{regexp} @dots{}]
2766 @cindex upgrading packages
2767 Upgrade all the installed packages. If one or more @var{regexp}s are
2768 specified, upgrade only installed packages whose name matches a
2769 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2771 Note that this upgrades package to the latest version of packages found
2772 in the distribution currently installed. To update your distribution,
2773 you should regularly run @command{guix pull} (@pxref{Invoking guix
2776 @item --do-not-upgrade[=@var{regexp} @dots{}]
2777 When used together with the @code{--upgrade} option, do @emph{not}
2778 upgrade any packages whose name matches a @var{regexp}. For example, to
2779 upgrade all packages in the current profile except those containing the
2780 substring ``emacs'':
2783 $ guix package --upgrade . --do-not-upgrade emacs
2786 @item @anchor{profile-manifest}--manifest=@var{file}
2787 @itemx -m @var{file}
2788 @cindex profile declaration
2789 @cindex profile manifest
2790 Create a new generation of the profile from the manifest object
2791 returned by the Scheme code in @var{file}.
2793 This allows you to @emph{declare} the profile's contents rather than
2794 constructing it through a sequence of @code{--install} and similar
2795 commands. The advantage is that @var{file} can be put under version
2796 control, copied to different machines to reproduce the same profile, and
2799 @c FIXME: Add reference to (guix profile) documentation when available.
2800 @var{file} must return a @dfn{manifest} object, which is roughly a list
2803 @findex packages->manifest
2805 (use-package-modules guile emacs)
2810 ;; Use a specific package output.
2811 (list guile-2.0 "debug")))
2814 @findex specifications->manifest
2815 In this example we have to know which modules define the @code{emacs}
2816 and @code{guile-2.0} variables to provide the right
2817 @code{use-package-modules} line, which can be cumbersome. We can
2818 instead provide regular package specifications and let
2819 @code{specifications->manifest} look up the corresponding package
2823 (specifications->manifest
2824 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2828 @cindex rolling back
2829 @cindex undoing transactions
2830 @cindex transactions, undoing
2831 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2832 the last transaction.
2834 When combined with options such as @code{--install}, roll back occurs
2835 before any other actions.
2837 When rolling back from the first generation that actually contains
2838 installed packages, the profile is made to point to the @dfn{zeroth
2839 generation}, which contains no files apart from its own metadata.
2841 After having rolled back, installing, removing, or upgrading packages
2842 overwrites previous future generations. Thus, the history of the
2843 generations in a profile is always linear.
2845 @item --switch-generation=@var{pattern}
2846 @itemx -S @var{pattern}
2848 Switch to a particular generation defined by @var{pattern}.
2850 @var{pattern} may be either a generation number or a number prefixed
2851 with ``+'' or ``-''. The latter means: move forward/backward by a
2852 specified number of generations. For example, if you want to return to
2853 the latest generation after @code{--roll-back}, use
2854 @code{--switch-generation=+1}.
2856 The difference between @code{--roll-back} and
2857 @code{--switch-generation=-1} is that @code{--switch-generation} will
2858 not make a zeroth generation, so if a specified generation does not
2859 exist, the current generation will not be changed.
2861 @item --search-paths[=@var{kind}]
2862 @cindex search paths
2863 Report environment variable definitions, in Bash syntax, that may be
2864 needed in order to use the set of installed packages. These environment
2865 variables are used to specify @dfn{search paths} for files used by some
2866 of the installed packages.
2868 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2869 environment variables to be defined so it can look for headers and
2870 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2871 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2872 library are installed in the profile, then @code{--search-paths} will
2873 suggest setting these variables to @code{@var{profile}/include} and
2874 @code{@var{profile}/lib}, respectively.
2876 The typical use case is to define these environment variables in the
2880 $ eval `guix package --search-paths`
2883 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2884 meaning that the returned environment variable definitions will either
2885 be exact settings, or prefixes or suffixes of the current value of these
2886 variables. When omitted, @var{kind} defaults to @code{exact}.
2888 This option can also be used to compute the @emph{combined} search paths
2889 of several profiles. Consider this example:
2892 $ guix package -p foo -i guile
2893 $ guix package -p bar -i guile-json
2894 $ guix package -p foo -p bar --search-paths
2897 The last command above reports about the @code{GUILE_LOAD_PATH}
2898 variable, even though, taken individually, neither @file{foo} nor
2899 @file{bar} would lead to that recommendation.
2902 @item --profile=@var{profile}
2903 @itemx -p @var{profile}
2904 Use @var{profile} instead of the user's default profile.
2906 @cindex collisions, in a profile
2907 @cindex colliding packages in profiles
2908 @cindex profile collisions
2909 @item --allow-collisions
2910 Allow colliding packages in the new profile. Use at your own risk!
2912 By default, @command{guix package} reports as an error @dfn{collisions}
2913 in the profile. Collisions happen when two or more different versions
2914 or variants of a given package end up in the profile.
2917 Use the bootstrap Guile to build the profile. This option is only
2918 useful to distribution developers.
2922 In addition to these actions, @command{guix package} supports the
2923 following options to query the current state of a profile, or the
2924 availability of packages:
2928 @item --search=@var{regexp}
2929 @itemx -s @var{regexp}
2930 @cindex searching for packages
2931 List the available packages whose name, synopsis, or description matches
2932 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
2933 Print all the metadata of matching packages in
2934 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
2935 GNU recutils manual}).
2937 This allows specific fields to be extracted using the @command{recsel}
2938 command, for instance:
2941 $ guix package -s malloc | recsel -p name,version,relevance
2955 Similarly, to show the name of all the packages available under the
2956 terms of the GNU@tie{}LGPL version 3:
2959 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
2966 It is also possible to refine search results using several @code{-s} flags to
2967 @command{guix package}, or several arguments to @command{guix search}. For
2968 example, the following command returns a list of board games (this time using
2969 the @command{guix search} alias):
2972 $ guix search '\<board\>' game | recsel -p name
2977 If we were to omit @code{-s game}, we would also get software packages
2978 that deal with printed circuit boards; removing the angle brackets
2979 around @code{board} would further add packages that have to do with
2982 And now for a more elaborate example. The following command searches
2983 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
2984 libraries, and prints the name and synopsis of the matching packages:
2987 $ guix search crypto library | \
2988 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
2992 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
2993 information on @dfn{selection expressions} for @code{recsel -e}.
2995 @item --show=@var{package}
2996 Show details about @var{package}, taken from the list of available packages, in
2997 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3001 $ guix package --show=python | recsel -p name,version
3009 You may also specify the full name of a package to only get details about a
3010 specific version of it:
3012 $ guix package --show=python@@3.4 | recsel -p name,version
3019 @item --list-installed[=@var{regexp}]
3020 @itemx -I [@var{regexp}]
3021 List the currently installed packages in the specified profile, with the
3022 most recently installed packages shown last. When @var{regexp} is
3023 specified, list only installed packages whose name matches @var{regexp}.
3025 For each installed package, print the following items, separated by
3026 tabs: the package name, its version string, the part of the package that
3027 is installed (for instance, @code{out} for the default output,
3028 @code{include} for its headers, etc.), and the path of this package in
3031 @item --list-available[=@var{regexp}]
3032 @itemx -A [@var{regexp}]
3033 List packages currently available in the distribution for this system
3034 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3035 installed packages whose name matches @var{regexp}.
3037 For each package, print the following items separated by tabs: its name,
3038 its version string, the parts of the package (@pxref{Packages with
3039 Multiple Outputs}), and the source location of its definition.
3041 @item --list-generations[=@var{pattern}]
3042 @itemx -l [@var{pattern}]
3044 Return a list of generations along with their creation dates; for each
3045 generation, show the installed packages, with the most recently
3046 installed packages shown last. Note that the zeroth generation is never
3049 For each installed package, print the following items, separated by
3050 tabs: the name of a package, its version string, the part of the package
3051 that is installed (@pxref{Packages with Multiple Outputs}), and the
3052 location of this package in the store.
3054 When @var{pattern} is used, the command returns only matching
3055 generations. Valid patterns include:
3058 @item @emph{Integers and comma-separated integers}. Both patterns denote
3059 generation numbers. For instance, @code{--list-generations=1} returns
3062 And @code{--list-generations=1,8,2} outputs three generations in the
3063 specified order. Neither spaces nor trailing commas are allowed.
3065 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3066 specified generations and everything in between. Note that the start of
3067 a range must be smaller than its end.
3069 It is also possible to omit the endpoint. For example,
3070 @code{--list-generations=2..}, returns all generations starting from the
3073 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3074 or months by passing an integer along with the first letter of the
3075 duration. For example, @code{--list-generations=20d} lists generations
3076 that are up to 20 days old.
3079 @item --delete-generations[=@var{pattern}]
3080 @itemx -d [@var{pattern}]
3081 When @var{pattern} is omitted, delete all generations except the current
3084 This command accepts the same patterns as @option{--list-generations}.
3085 When @var{pattern} is specified, delete the matching generations. When
3086 @var{pattern} specifies a duration, generations @emph{older} than the
3087 specified duration match. For instance, @code{--delete-generations=1m}
3088 deletes generations that are more than one month old.
3090 If the current generation matches, it is @emph{not} deleted. Also, the
3091 zeroth generation is never deleted.
3093 Note that deleting generations prevents rolling back to them.
3094 Consequently, this command must be used with care.
3098 Finally, since @command{guix package} may actually start build
3099 processes, it supports all the common build options (@pxref{Common Build
3100 Options}). It also supports package transformation options, such as
3101 @option{--with-source} (@pxref{Package Transformation Options}).
3102 However, note that package transformations are lost when upgrading; to
3103 preserve transformations across upgrades, you should define your own
3104 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3105 (@pxref{Defining Packages}).
3108 @section Substitutes
3111 @cindex pre-built binaries
3112 Guix supports transparent source/binary deployment, which means that it
3113 can either build things locally, or download pre-built items from a
3114 server, or both. We call these pre-built items @dfn{substitutes}---they
3115 are substitutes for local build results. In many cases, downloading a
3116 substitute is much faster than building things locally.
3118 Substitutes can be anything resulting from a derivation build
3119 (@pxref{Derivations}). Of course, in the common case, they are
3120 pre-built package binaries, but source tarballs, for instance, which
3121 also result from derivation builds, can be available as substitutes.
3124 * Official Substitute Server:: One particular source of substitutes.
3125 * Substitute Server Authorization:: How to enable or disable substitutes.
3126 * Substitute Authentication:: How Guix verifies substitutes.
3127 * Proxy Settings:: How to get substitutes via proxy.
3128 * Substitution Failure:: What happens when substitution fails.
3129 * On Trusting Binaries:: How can you trust that binary blob?
3132 @node Official Substitute Server
3133 @subsection Official Substitute Server
3137 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3138 that builds packages from Guix continuously for some
3139 architectures, and makes them available as substitutes. This is the
3140 default source of substitutes; it can be overridden by passing the
3141 @option{--substitute-urls} option either to @command{guix-daemon}
3142 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3143 or to client tools such as @command{guix package}
3144 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3147 Substitute URLs can be either HTTP or HTTPS.
3148 HTTPS is recommended because communications are encrypted; conversely,
3149 using HTTP makes all communications visible to an eavesdropper, who
3150 could use the information gathered to determine, for instance, whether
3151 your system has unpatched security vulnerabilities.
3153 Substitutes from the official build farm are enabled by default when
3154 using Guix System (@pxref{GNU Distribution}). However,
3155 they are disabled by default when using Guix on a foreign distribution,
3156 unless you have explicitly enabled them via one of the recommended
3157 installation steps (@pxref{Installation}). The following paragraphs
3158 describe how to enable or disable substitutes for the official build
3159 farm; the same procedure can also be used to enable substitutes for any
3160 other substitute server.
3162 @node Substitute Server Authorization
3163 @subsection Substitute Server Authorization
3166 @cindex substitutes, authorization thereof
3167 @cindex access control list (ACL), for substitutes
3168 @cindex ACL (access control list), for substitutes
3169 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3171 must add its public key to the access control list (ACL) of archive
3172 imports, using the @command{guix archive} command (@pxref{Invoking guix
3173 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3174 be compromised and to serve genuine substitutes.
3176 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3177 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3178 the installation prefix of Guix. If you installed Guix from source,
3179 make sure you checked the GPG signature of
3180 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3181 Then, you can run something like this:
3184 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3188 Similarly, the @file{hydra.gnu.org.pub} file contains the public key
3189 of an independent build farm also run by the project, reachable at
3190 @indicateurl{https://mirror.hydra.gnu.org}.
3193 Once this is in place, the output of a command like @code{guix build}
3194 should change from something like:
3197 $ guix build emacs --dry-run
3198 The following derivations would be built:
3199 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3200 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3201 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3202 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3210 $ guix build emacs --dry-run
3211 112.3 MB would be downloaded:
3212 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3213 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3214 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3215 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3220 This indicates that substitutes from @code{@value{SUBSTITUTE-SERVER}} are usable and
3221 will be downloaded, when possible, for future builds.
3223 @cindex substitutes, how to disable
3224 The substitute mechanism can be disabled globally by running
3225 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3226 guix-daemon}). It can also be disabled temporarily by passing the
3227 @code{--no-substitutes} option to @command{guix package}, @command{guix
3228 build}, and other command-line tools.
3230 @node Substitute Authentication
3231 @subsection Substitute Authentication
3233 @cindex digital signatures
3234 Guix detects and raises an error when attempting to use a substitute
3235 that has been tampered with. Likewise, it ignores substitutes that are
3236 not signed, or that are not signed by one of the keys listed in the ACL.
3238 There is one exception though: if an unauthorized server provides
3239 substitutes that are @emph{bit-for-bit identical} to those provided by
3240 an authorized server, then the unauthorized server becomes eligible for
3241 downloads. For example, assume we have chosen two substitute servers
3245 --substitute-urls="https://a.example.org https://b.example.org"
3249 @cindex reproducible builds
3250 If the ACL contains only the key for @code{b.example.org}, and if
3251 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3252 then Guix will download substitutes from @code{a.example.org} because it
3253 comes first in the list and can be considered a mirror of
3254 @code{b.example.org}. In practice, independent build machines usually
3255 produce the same binaries, thanks to bit-reproducible builds (see
3258 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3259 (in other words, the server is not authenticated), contrary to what
3260 HTTPS clients such as Web browsers usually do. This is because Guix
3261 authenticates substitute information itself, as explained above, which
3262 is what we care about (whereas X.509 certificates are about
3263 authenticating bindings between domain names and public keys.)
3265 @node Proxy Settings
3266 @subsection Proxy Settings
3269 Substitutes are downloaded over HTTP or HTTPS.
3270 The @code{http_proxy} environment
3271 variable can be set in the environment of @command{guix-daemon} and is
3272 honored for downloads of substitutes. Note that the value of
3273 @code{http_proxy} in the environment where @command{guix build},
3274 @command{guix package}, and other client commands are run has
3275 @emph{absolutely no effect}.
3277 @node Substitution Failure
3278 @subsection Substitution Failure
3280 Even when a substitute for a derivation is available, sometimes the
3281 substitution attempt will fail. This can happen for a variety of
3282 reasons: the substitute server might be offline, the substitute may
3283 recently have been deleted, the connection might have been interrupted,
3286 When substitutes are enabled and a substitute for a derivation is
3287 available, but the substitution attempt fails, Guix will attempt to
3288 build the derivation locally depending on whether or not
3289 @code{--fallback} was given (@pxref{fallback-option,, common build
3290 option @code{--fallback}}). Specifically, if @code{--fallback} was
3291 omitted, then no local build will be performed, and the derivation is
3292 considered to have failed. However, if @code{--fallback} was given,
3293 then Guix will attempt to build the derivation locally, and the success
3294 or failure of the derivation depends on the success or failure of the
3295 local build. Note that when substitutes are disabled or no substitute
3296 is available for the derivation in question, a local build will
3297 @emph{always} be performed, regardless of whether or not
3298 @code{--fallback} was given.
3300 To get an idea of how many substitutes are available right now, you can
3301 try running the @command{guix weather} command (@pxref{Invoking guix
3302 weather}). This command provides statistics on the substitutes provided
3305 @node On Trusting Binaries
3306 @subsection On Trusting Binaries
3308 @cindex trust, of pre-built binaries
3309 Today, each individual's control over their own computing is at the
3310 mercy of institutions, corporations, and groups with enough power and
3311 determination to subvert the computing infrastructure and exploit its
3312 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3313 convenient, we encourage users to also build on their own, or even run
3314 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3315 interesting target. One way to help is by publishing the software you
3316 build using @command{guix publish} so that others have one more choice
3317 of server to download substitutes from (@pxref{Invoking guix publish}).
3319 Guix has the foundations to maximize build reproducibility
3320 (@pxref{Features}). In most cases, independent builds of a given
3321 package or derivation should yield bit-identical results. Thus, through
3322 a diverse set of independent package builds, we can strengthen the
3323 integrity of our systems. The @command{guix challenge} command aims to
3324 help users assess substitute servers, and to assist developers in
3325 finding out about non-deterministic package builds (@pxref{Invoking guix
3326 challenge}). Similarly, the @option{--check} option of @command{guix
3327 build} allows users to check whether previously-installed substitutes
3328 are genuine by rebuilding them locally (@pxref{build-check,
3329 @command{guix build --check}}).
3331 In the future, we want Guix to have support to publish and retrieve
3332 binaries to/from other users, in a peer-to-peer fashion. If you would
3333 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3335 @node Packages with Multiple Outputs
3336 @section Packages with Multiple Outputs
3338 @cindex multiple-output packages
3339 @cindex package outputs
3342 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3343 source package leads to exactly one directory in the store. When running
3344 @command{guix install glibc}, one installs the default output of the
3345 GNU libc package; the default output is called @code{out}, but its name
3346 can be omitted as shown in this command. In this particular case, the
3347 default output of @code{glibc} contains all the C header files, shared
3348 libraries, static libraries, Info documentation, and other supporting
3351 Sometimes it is more appropriate to separate the various types of files
3352 produced from a single source package into separate outputs. For
3353 instance, the GLib C library (used by GTK+ and related packages)
3354 installs more than 20 MiB of reference documentation as HTML pages.
3355 To save space for users who do not need it, the documentation goes to a
3356 separate output, called @code{doc}. To install the main GLib output,
3357 which contains everything but the documentation, one would run:
3363 @cindex documentation
3364 The command to install its documentation is:
3367 guix install glib:doc
3370 Some packages install programs with different ``dependency footprints''.
3371 For instance, the WordNet package installs both command-line tools and
3372 graphical user interfaces (GUIs). The former depend solely on the C
3373 library, whereas the latter depend on Tcl/Tk and the underlying X
3374 libraries. In this case, we leave the command-line tools in the default
3375 output, whereas the GUIs are in a separate output. This allows users
3376 who do not need the GUIs to save space. The @command{guix size} command
3377 can help find out about such situations (@pxref{Invoking guix size}).
3378 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3380 There are several such multiple-output packages in the GNU distribution.
3381 Other conventional output names include @code{lib} for libraries and
3382 possibly header files, @code{bin} for stand-alone programs, and
3383 @code{debug} for debugging information (@pxref{Installing Debugging
3384 Files}). The outputs of a packages are listed in the third column of
3385 the output of @command{guix package --list-available} (@pxref{Invoking
3389 @node Invoking guix gc
3390 @section Invoking @command{guix gc}
3392 @cindex garbage collector
3394 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3395 The @command{guix gc} command allows users to explicitly run the garbage
3396 collector to reclaim space from the @file{/gnu/store} directory. It is
3397 the @emph{only} way to remove files from @file{/gnu/store}---removing
3398 files or directories manually may break it beyond repair!
3401 @cindex garbage collector roots
3402 The garbage collector has a set of known @dfn{roots}: any file under
3403 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3404 cannot be deleted; any other file is considered @dfn{dead} and may be
3405 deleted. The set of garbage collector roots (``GC roots'' for short)
3406 includes default user profiles; by default, the symlinks under
3407 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3408 added with @command{guix build --root}, for example (@pxref{Invoking
3409 guix build}). The @command{guix gc --list-roots} command lists them.
3411 Prior to running @code{guix gc --collect-garbage} to make space, it is
3412 often useful to remove old generations from user profiles; that way, old
3413 package builds referenced by those generations can be reclaimed. This
3414 is achieved by running @code{guix package --delete-generations}
3415 (@pxref{Invoking guix package}).
3417 Our recommendation is to run a garbage collection periodically, or when
3418 you are short on disk space. For instance, to guarantee that at least
3419 5@tie{}GB are available on your disk, simply run:
3425 It is perfectly safe to run as a non-interactive periodic job
3426 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3427 Running @command{guix gc} with no arguments will collect as
3428 much garbage as it can, but that is often inconvenient: you may find
3429 yourself having to rebuild or re-download software that is ``dead'' from
3430 the GC viewpoint but that is necessary to build other pieces of
3431 software---e.g., the compiler tool chain.
3433 The @command{guix gc} command has three modes of operation: it can be
3434 used to garbage-collect any dead files (the default), to delete specific
3435 files (the @code{--delete} option), to print garbage-collector
3436 information, or for more advanced queries. The garbage collection
3437 options are as follows:
3440 @item --collect-garbage[=@var{min}]
3441 @itemx -C [@var{min}]
3442 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3443 sub-directories. This is the default operation when no option is
3446 When @var{min} is given, stop once @var{min} bytes have been collected.
3447 @var{min} may be a number of bytes, or it may include a unit as a
3448 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3449 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3451 When @var{min} is omitted, collect all the garbage.
3453 @item --free-space=@var{free}
3454 @itemx -F @var{free}
3455 Collect garbage until @var{free} space is available under
3456 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3457 as @code{500MiB}, as described above.
3459 When @var{free} or more is already available in @file{/gnu/store}, do
3460 nothing and exit immediately.
3462 @item --delete-generations[=@var{duration}]
3463 @itemx -d [@var{duration}]
3464 Before starting the garbage collection process, delete all the generations
3465 older than @var{duration}, for all the user profiles; when run as root, this
3466 applies to all the profiles @emph{of all the users}.
3468 For example, this command deletes all the generations of all your profiles
3469 that are older than 2 months (except generations that are current), and then
3470 proceeds to free space until at least 10 GiB are available:
3473 guix gc -d 2m -F 10G
3478 Attempt to delete all the store files and directories specified as
3479 arguments. This fails if some of the files are not in the store, or if
3480 they are still live.
3482 @item --list-failures
3483 List store items corresponding to cached build failures.
3485 This prints nothing unless the daemon was started with
3486 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3487 @option{--cache-failures}}).
3490 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3493 @item --clear-failures
3494 Remove the specified store items from the failed-build cache.
3496 Again, this option only makes sense when the daemon is started with
3497 @option{--cache-failures}. Otherwise, it does nothing.
3500 Show the list of dead files and directories still present in the
3501 store---i.e., files and directories no longer reachable from any root.
3504 Show the list of live store files and directories.
3508 In addition, the references among existing store files can be queried:
3514 @cindex package dependencies
3515 List the references (respectively, the referrers) of store files given
3521 List the requisites of the store files passed as arguments. Requisites
3522 include the store files themselves, their references, and the references
3523 of these, recursively. In other words, the returned list is the
3524 @dfn{transitive closure} of the store files.
3526 @xref{Invoking guix size}, for a tool to profile the size of the closure
3527 of an element. @xref{Invoking guix graph}, for a tool to visualize
3528 the graph of references.
3532 Return the derivation(s) leading to the given store items
3533 (@pxref{Derivations}).
3535 For example, this command:
3538 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3542 returns the @file{.drv} file(s) leading to the @code{emacs} package
3543 installed in your profile.
3545 Note that there may be zero matching @file{.drv} files, for instance
3546 because these files have been garbage-collected. There can also be more
3547 than one matching @file{.drv} due to fixed-output derivations.
3550 Lastly, the following options allow you to check the integrity of the
3551 store and to control disk usage.
3555 @item --verify[=@var{options}]
3556 @cindex integrity, of the store
3557 @cindex integrity checking
3558 Verify the integrity of the store.
3560 By default, make sure that all the store items marked as valid in the
3561 database of the daemon actually exist in @file{/gnu/store}.
3563 When provided, @var{options} must be a comma-separated list containing one
3564 or more of @code{contents} and @code{repair}.
3566 When passing @option{--verify=contents}, the daemon computes the
3567 content hash of each store item and compares it against its hash in the
3568 database. Hash mismatches are reported as data corruptions. Because it
3569 traverses @emph{all the files in the store}, this command can take a
3570 long time, especially on systems with a slow disk drive.
3572 @cindex repairing the store
3573 @cindex corruption, recovering from
3574 Using @option{--verify=repair} or @option{--verify=contents,repair}
3575 causes the daemon to try to repair corrupt store items by fetching
3576 substitutes for them (@pxref{Substitutes}). Because repairing is not
3577 atomic, and thus potentially dangerous, it is available only to the
3578 system administrator. A lightweight alternative, when you know exactly
3579 which items in the store are corrupt, is @command{guix build --repair}
3580 (@pxref{Invoking guix build}).
3583 @cindex deduplication
3584 Optimize the store by hard-linking identical files---this is
3585 @dfn{deduplication}.
3587 The daemon performs deduplication after each successful build or archive
3588 import, unless it was started with @code{--disable-deduplication}
3589 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3590 this option is primarily useful when the daemon was running with
3591 @code{--disable-deduplication}.
3595 @node Invoking guix pull
3596 @section Invoking @command{guix pull}
3598 @cindex upgrading Guix
3599 @cindex updating Guix
3600 @cindex @command{guix pull}
3602 Packages are installed or upgraded to the latest version available in
3603 the distribution currently available on your local machine. To update
3604 that distribution, along with the Guix tools, you must run @command{guix
3605 pull}: the command downloads the latest Guix source code and package
3606 descriptions, and deploys it. Source code is downloaded from a
3607 @uref{https://git-scm.com, Git} repository, by default the official
3608 GNU@tie{}Guix repository, though this can be customized.
3610 On completion, @command{guix package} will use packages and package
3611 versions from this just-retrieved copy of Guix. Not only that, but all
3612 the Guix commands and Scheme modules will also be taken from that latest
3613 version. New @command{guix} sub-commands added by the update also
3616 Any user can update their Guix copy using @command{guix pull}, and the
3617 effect is limited to the user who run @command{guix pull}. For
3618 instance, when user @code{root} runs @command{guix pull}, this has no
3619 effect on the version of Guix that user @code{alice} sees, and vice
3622 The result of running @command{guix pull} is a @dfn{profile} available
3623 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3624 make sure to add it to the beginning of your search path so that you use
3625 the latest version, and similarly for the Info manual
3626 (@pxref{Documentation}):
3629 export PATH="$HOME/.config/guix/current/bin:$PATH"
3630 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3633 The @code{--list-generations} or @code{-l} option lists past generations
3634 produced by @command{guix pull}, along with details about their provenance:
3638 Generation 1 Jun 10 2018 00:18:18
3640 repository URL: https://git.savannah.gnu.org/git/guix.git
3641 branch: origin/master
3642 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3644 Generation 2 Jun 11 2018 11:02:49
3646 repository URL: https://git.savannah.gnu.org/git/guix.git
3647 branch: origin/master
3648 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3649 2 new packages: keepalived, libnfnetlink
3650 6 packages upgraded: emacs-nix-mode@@2.0.4,
3651 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3652 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3654 Generation 3 Jun 13 2018 23:31:07 (current)
3656 repository URL: https://git.savannah.gnu.org/git/guix.git
3657 branch: origin/master
3658 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3659 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3660 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3663 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3664 describe the current status of Guix.
3666 This @code{~/.config/guix/current} profile works like any other profile
3667 created by @command{guix package} (@pxref{Invoking guix package}). That
3668 is, you can list generations, roll back to the previous
3669 generation---i.e., the previous Guix---and so on:
3672 $ guix package -p ~/.config/guix/current --roll-back
3673 switched from generation 3 to 2
3674 $ guix package -p ~/.config/guix/current --delete-generations=1
3675 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3678 The @command{guix pull} command is usually invoked with no arguments,
3679 but it supports the following options:
3682 @item --url=@var{url}
3683 @itemx --commit=@var{commit}
3684 @itemx --branch=@var{branch}
3685 Download code for the @code{guix} channel from the specified @var{url}, at the
3686 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3687 string), or @var{branch}.
3689 @cindex @file{channels.scm}, configuration file
3690 @cindex configuration file for channels
3691 These options are provided for convenience, but you can also specify your
3692 configuration in the @file{~/.config/guix/channels.scm} file or using the
3693 @option{--channels} option (see below).
3695 @item --channels=@var{file}
3696 @itemx -C @var{file}
3697 Read the list of channels from @var{file} instead of
3698 @file{~/.config/guix/channels.scm}. @var{file} must contain Scheme code that
3699 evaluates to a list of channel objects. @xref{Channels}, for more
3704 Display the list of packages added or upgraded since the previous generation.
3706 This is the same information as displayed upon @command{guix pull} completion,
3707 but without ellipses; it is also similar to the output of @command{guix pull
3708 -l} for the last generation (see below).
3710 @item --list-generations[=@var{pattern}]
3711 @itemx -l [@var{pattern}]
3712 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3713 is provided, the subset of generations that match @var{pattern}.
3714 The syntax of @var{pattern} is the same as with @code{guix package
3715 --list-generations} (@pxref{Invoking guix package}).
3717 @xref{Invoking guix describe}, for a way to display information about the
3718 current generation only.
3720 @item --profile=@var{profile}
3721 @itemx -p @var{profile}
3722 Use @var{profile} instead of @file{~/.config/guix/current}.
3726 Show which channel commit(s) would be used and what would be built or
3727 substituted but do not actually do it.
3729 @item --system=@var{system}
3730 @itemx -s @var{system}
3731 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3732 the system type of the build host.
3735 Produce verbose output, writing build logs to the standard error output.
3738 Use the bootstrap Guile to build the latest Guix. This option is only
3739 useful to Guix developers.
3742 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3743 repository and branch to pull from, as well as @emph{additional} repositories
3744 containing package modules that should be deployed. @xref{Channels}, for more
3747 In addition, @command{guix pull} supports all the common build options
3748 (@pxref{Common Build Options}).
3754 @cindex @file{channels.scm}, configuration file
3755 @cindex configuration file for channels
3756 @cindex @command{guix pull}, configuration file
3757 @cindex configuration of @command{guix pull}
3758 Guix and its package collection are updated by running @command{guix pull}
3759 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3760 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3761 customized by defining @dfn{channels} in the
3762 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3763 of a Git repository to be deployed, and @command{guix pull} can be instructed
3764 to pull from one or more channels. In other words, channels can be used to
3765 @emph{customize} and to @emph{extend} Guix, as we will see below.
3767 @subsection Using a Custom Guix Channel
3769 The channel called @code{guix} specifies where Guix itself---its command-line
3770 tools as well as its package collection---should be downloaded. For instance,
3771 suppose you want to update from your own copy of the Guix repository at
3772 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3773 write in @code{~/.config/guix/channels.scm} this specification:
3776 ;; Tell 'guix pull' to use my own repo.
3779 (url "https://example.org/my-guix.git")
3780 (branch "super-hacks")))
3784 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3785 branch of the repository at @code{example.org}.
3787 @subsection Specifying Additional Channels
3789 @cindex extending the package collection (channels)
3790 @cindex personal packages (channels)
3791 @cindex channels, for personal packages
3792 You can also specify @emph{additional channels} to pull from. Let's say you
3793 have a bunch of custom package variants or personal packages that you think
3794 would make little sense to contribute to the Guix project, but would like to
3795 have these packages transparently available to you at the command line. You
3796 would first write modules containing those package definitions (@pxref{Package
3797 Modules}), maintain them in a Git repository, and then you and anyone else can
3798 use it as an additional channel to get packages from. Neat, no?
3800 @c What follows stems from discussions at
3801 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3802 @c earlier discussions on guix-devel@gnu.org.
3804 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3805 publish your personal channel to the world, we would like to share a few words
3810 Before publishing a channel, please consider contributing your package
3811 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3812 to free software of all sorts, and packages in Guix proper are readily
3813 available to all Guix users and benefit from the project's quality assurance
3817 When you maintain package definitions outside Guix, we, Guix developers,
3818 consider that @emph{the compatibility burden is on you}. Remember that
3819 package modules and package definitions are just Scheme code that uses various
3820 programming interfaces (APIs). We want to remain free to change these APIs to
3821 keep improving Guix, possibly in ways that break your channel. We never
3822 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
3826 Corollary: if you're using an external channel and that channel breaks, please
3827 @emph{report the issue to the channel authors}, not to the Guix project.
3830 You've been warned! Having said this, we believe external channels are a
3831 practical way to exert your freedom to augment Guix' package collection and to
3832 share your improvements, which are basic tenets of
3833 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
3834 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
3837 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
3838 @command{guix pull} to pull from it @emph{in addition} to the default Guix
3841 @vindex %default-channels
3843 ;; Add my personal packages to those Guix provides.
3845 (name 'my-personal-packages)
3846 (url "https://example.org/personal-packages.git"))
3851 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
3852 add a channel the list of channels that the variable @code{%default-channels}
3853 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
3854 Manual}). With this file in place, @command{guix pull} builds not only Guix
3855 but also the package modules from your own repository. The result in
3856 @file{~/.config/guix/current} is the union of Guix with your own package
3860 $ guix pull --list-generations
3862 Generation 19 Aug 27 2018 16:20:48
3864 repository URL: https://git.savannah.gnu.org/git/guix.git
3866 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
3867 my-personal-packages dd3df5e
3868 repository URL: https://example.org/personal-packages.git
3870 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
3871 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
3872 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
3876 The output of @command{guix pull} above shows that Generation@tie{}19 includes
3877 both Guix and packages from the @code{my-personal-packages} channel. Among
3878 the new and upgraded packages that are listed, some like @code{my-gimp} and
3879 @code{my-emacs-with-cool-features} might come from
3880 @code{my-personal-packages}, while others come from the Guix default channel.
3882 To create a channel, create a Git repository containing your own package
3883 modules and make it available. The repository can contain anything, but a
3884 useful channel will contain Guile modules that export packages. Once you
3885 start using a channel, Guix will behave as if the root directory of that
3886 channel's Git repository has been added to the Guile load path (@pxref{Load
3887 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
3888 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
3889 module, then the module will be available under the name @code{(my-packages
3890 my-tools)}, and you will be able to use it like any other module
3891 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
3893 @cindex dependencies, channels
3894 @cindex meta-data, channels
3895 @subsection Declaring Channel Dependencies
3897 Channel authors may decide to augment a package collection provided by other
3898 channels. They can declare their channel to be dependent on other channels in
3899 a meta-data file @file{.guix-channel}, which is to be placed in the root of
3900 the channel repository.
3902 The meta-data file should contain a simple S-expression like this:
3909 (name some-collection)
3910 (url "https://example.org/first-collection.git"))
3912 (name some-other-collection)
3913 (url "https://example.org/second-collection.git")
3914 (branch "testing"))))
3917 In the above example this channel is declared to depend on two other channels,
3918 which will both be fetched automatically. The modules provided by the channel
3919 will be compiled in an environment where the modules of all these declared
3920 channels are available.
3922 For the sake of reliability and maintainability, you should avoid dependencies
3923 on channels that you don't control, and you should aim to keep the number of
3924 dependencies to a minimum.
3926 @subsection Replicating Guix
3928 @cindex pinning, channels
3929 @cindex replicating Guix
3930 @cindex reproducibility, of Guix
3931 The @command{guix pull --list-generations} output above shows precisely which
3932 commits were used to build this instance of Guix. We can thus replicate it,
3933 say, on another machine, by providing a channel specification in
3934 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
3937 ;; Deploy specific commits of my channels of interest.
3940 (url "https://git.savannah.gnu.org/git/guix.git")
3941 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
3943 (name 'my-personal-packages)
3944 (url "https://example.org/personal-packages.git")
3945 (branch "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
3948 The @command{guix describe --format=channels} command can even generate this
3949 list of channels directly (@pxref{Invoking guix describe}).
3951 At this point the two machines run the @emph{exact same Guix}, with access to
3952 the @emph{exact same packages}. The output of @command{guix build gimp} on
3953 one machine will be exactly the same, bit for bit, as the output of the same
3954 command on the other machine. It also means both machines have access to all
3955 the source code of Guix and, transitively, to all the source code of every
3958 This gives you super powers, allowing you to track the provenance of binary
3959 artifacts with very fine grain, and to reproduce software environments at
3960 will---some sort of ``meta reproducibility'' capabilities, if you will.
3961 @xref{Inferiors}, for another way to take advantage of these super powers.
3966 @c TODO: Remove this once we're more confident about API stability.
3968 The functionality described here is a ``technology preview'' as of version
3969 @value{VERSION}. As such, the interface is subject to change.
3973 @cindex composition of Guix revisions
3974 Sometimes you might need to mix packages from the revision of Guix you're
3975 currently running with packages available in a different revision of Guix.
3976 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
3977 revisions in arbitrary ways.
3979 @cindex inferior packages
3980 Technically, an ``inferior'' is essentially a separate Guix process connected
3981 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
3982 @code{(guix inferior)} module allows you to create inferiors and to
3983 communicate with them. It also provides a high-level interface to browse and
3984 manipulate the packages that an inferior provides---@dfn{inferior packages}.
3986 When combined with channels (@pxref{Channels}), inferiors provide a simple way
3987 to interact with a separate revision of Guix. For example, let's assume you
3988 want to install in your profile the current @code{guile} package, along with
3989 the @code{guile-json} as it existed in an older revision of Guix---perhaps
3990 because the newer @code{guile-json} has an incompatible API and you want to
3991 run your code against the old API@. To do that, you could write a manifest for
3992 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
3993 manifest, you would create an inferior for that old Guix revision you care
3994 about, and you would look up the @code{guile-json} package in the inferior:
3997 (use-modules (guix inferior) (guix channels)
3998 (srfi srfi-1)) ;for 'first'
4001 ;; This is the old revision from which we want to
4002 ;; extract guile-json.
4005 (url "https://git.savannah.gnu.org/git/guix.git")
4007 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4010 ;; An inferior representing the above revision.
4011 (inferior-for-channels channels))
4013 ;; Now create a manifest with the current "guile" package
4014 ;; and the old "guile-json" package.
4016 (list (first (lookup-inferior-packages inferior "guile-json"))
4017 (specification->package "guile")))
4020 On its first run, @command{guix package --manifest} might have to build the
4021 channel you specified before it can create the inferior; subsequent runs will
4022 be much faster because the Guix revision will be cached.
4024 The @code{(guix inferior)} module provides the following procedures to open an
4027 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4028 [#:cache-directory] [#:ttl]
4029 Return an inferior for @var{channels}, a list of channels. Use the cache at
4030 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4031 This procedure opens a new connection to the build daemon.
4033 As a side effect, this procedure may build or substitute binaries for
4034 @var{channels}, which can take time.
4037 @deffn {Scheme Procedure} open-inferior @var{directory} @
4038 [#:command "bin/guix"]
4039 Open the inferior Guix in @var{directory}, running
4040 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4041 the inferior could not be launched.
4044 @cindex inferior packages
4045 The procedures listed below allow you to obtain and manipulate inferior
4048 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4049 Return the list of packages known to @var{inferior}.
4052 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4054 Return the sorted list of inferior packages matching @var{name} in
4055 @var{inferior}, with highest version numbers first. If @var{version} is true,
4056 return only packages with a version number prefixed by @var{version}.
4059 @deffn {Scheme Procedure} inferior-package? @var{obj}
4060 Return true if @var{obj} is an inferior package.
4063 @deffn {Scheme Procedure} inferior-package-name @var{package}
4064 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4065 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4066 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4067 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4068 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4069 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4070 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4071 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4072 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4073 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4074 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4075 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4076 These procedures are the counterpart of package record accessors
4077 (@pxref{package Reference}). Most of them work by querying the inferior
4078 @var{package} comes from, so the inferior must still be live when you call
4082 Inferior packages can be used transparently like any other package or
4083 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4084 transparently handled by the @code{packages->manifest} procedure, which is
4085 commonly use in manifests (@pxref{Invoking guix package, the
4086 @option{--manifest} option of @command{guix package}}). Thus you can insert
4087 an inferior package pretty much anywhere you would insert a regular package:
4088 in manifests, in the @code{packages} field of your @code{operating-system}
4089 declaration, and so on.
4091 @node Invoking guix describe
4092 @section Invoking @command{guix describe}
4094 @cindex reproducibility
4095 @cindex replicating Guix
4096 Often you may want to answer questions like: ``Which revision of Guix am I
4097 using?'' or ``Which channels am I using?'' This is useful information in many
4098 situations: if you want to @emph{replicate} an environment on a different
4099 machine or user account, if you want to report a bug or to determine what
4100 change in the channels you are using caused it, or if you want to record your
4101 system state for reproducibility purposes. The @command{guix describe}
4102 command answers these questions.
4104 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4105 displays the channel(s) that it was built from, including their repository URL
4106 and commit IDs (@pxref{Channels}):
4110 Generation 10 Sep 03 2018 17:32:44 (current)
4112 repository URL: https://git.savannah.gnu.org/git/guix.git
4114 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4117 If you're familiar with the Git version control system, this is similar in
4118 spirit to @command{git describe}; the output is also similar to that of
4119 @command{guix pull --list-generations}, but limited to the current generation
4120 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4121 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4122 information is all it takes to describe the revision of Guix you're using, and
4123 also to replicate it.
4125 To make it easier to replicate Guix, @command{guix describe} can also be asked
4126 to return a list of channels instead of the human-readable description above:
4129 $ guix describe -f channels
4132 (url "https://git.savannah.gnu.org/git/guix.git")
4134 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4138 You can save this to a file and feed it to @command{guix pull -C} on some
4139 other machine or at a later point in time, which will instantiate @emph{this
4140 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4141 From there on, since you're able to deploy the same revision of Guix, you can
4142 just as well @emph{replicate a complete software environment}. We humbly
4143 think that this is @emph{awesome}, and we hope you'll like it too!
4145 The details of the options supported by @command{guix describe} are as
4149 @item --format=@var{format}
4150 @itemx -f @var{format}
4151 Produce output in the specified @var{format}, one of:
4155 produce human-readable output;
4157 produce a list of channel specifications that can be passed to @command{guix
4158 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4162 produce a list of channel specifications in JSON format;
4164 produce a list of channel specifications in Recutils format.
4167 @item --profile=@var{profile}
4168 @itemx -p @var{profile}
4169 Display information about @var{profile}.
4172 @node Invoking guix archive
4173 @section Invoking @command{guix archive}
4175 @cindex @command{guix archive}
4177 The @command{guix archive} command allows users to @dfn{export} files
4178 from the store into a single archive, and to later @dfn{import} them on
4179 a machine that runs Guix.
4180 In particular, it allows store files to be transferred from one machine
4181 to the store on another machine.
4184 If you're looking for a way to produce archives in a format suitable for
4185 tools other than Guix, @pxref{Invoking guix pack}.
4188 @cindex exporting store items
4189 To export store files as an archive to standard output, run:
4192 guix archive --export @var{options} @var{specifications}...
4195 @var{specifications} may be either store file names or package
4196 specifications, as for @command{guix package} (@pxref{Invoking guix
4197 package}). For instance, the following command creates an archive
4198 containing the @code{gui} output of the @code{git} package and the main
4199 output of @code{emacs}:
4202 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4205 If the specified packages are not built yet, @command{guix archive}
4206 automatically builds them. The build process may be controlled with the
4207 common build options (@pxref{Common Build Options}).
4209 To transfer the @code{emacs} package to a machine connected over SSH,
4213 guix archive --export -r emacs | ssh the-machine guix archive --import
4217 Similarly, a complete user profile may be transferred from one machine
4218 to another like this:
4221 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4222 ssh the-machine guix-archive --import
4226 However, note that, in both examples, all of @code{emacs} and the
4227 profile as well as all of their dependencies are transferred (due to
4228 @code{-r}), regardless of what is already available in the store on the
4229 target machine. The @code{--missing} option can help figure out which
4230 items are missing from the target store. The @command{guix copy}
4231 command simplifies and optimizes this whole process, so this is probably
4232 what you should use in this case (@pxref{Invoking guix copy}).
4234 @cindex nar, archive format
4235 @cindex normalized archive (nar)
4236 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4237 comparable in spirit to `tar', but with differences
4238 that make it more appropriate for our purposes. First, rather than
4239 recording all Unix metadata for each file, the nar format only mentions
4240 the file type (regular, directory, or symbolic link); Unix permissions
4241 and owner/group are dismissed. Second, the order in which directory
4242 entries are stored always follows the order of file names according to
4243 the C locale collation order. This makes archive production fully
4246 When exporting, the daemon digitally signs the contents of the archive,
4247 and that digital signature is appended. When importing, the daemon
4248 verifies the signature and rejects the import in case of an invalid
4249 signature or if the signing key is not authorized.
4250 @c FIXME: Add xref to daemon doc about signatures.
4252 The main options are:
4256 Export the specified store files or packages (see below.) Write the
4257 resulting archive to the standard output.
4259 Dependencies are @emph{not} included in the output, unless
4260 @code{--recursive} is passed.
4264 When combined with @code{--export}, this instructs @command{guix
4265 archive} to include dependencies of the given items in the archive.
4266 Thus, the resulting archive is self-contained: it contains the closure
4267 of the exported store items.
4270 Read an archive from the standard input, and import the files listed
4271 therein into the store. Abort if the archive has an invalid digital
4272 signature, or if it is signed by a public key not among the authorized
4273 keys (see @code{--authorize} below.)
4276 Read a list of store file names from the standard input, one per line,
4277 and write on the standard output the subset of these files missing from
4280 @item --generate-key[=@var{parameters}]
4281 @cindex signing, archives
4282 Generate a new key pair for the daemon. This is a prerequisite before
4283 archives can be exported with @code{--export}. Note that this operation
4284 usually takes time, because it needs to gather enough entropy to
4285 generate the key pair.
4287 The generated key pair is typically stored under @file{/etc/guix}, in
4288 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4289 key, which must be kept secret.) When @var{parameters} is omitted,
4290 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4291 versions before 1.6.0, it is a 4096-bit RSA key.
4292 Alternatively, @var{parameters} can specify
4293 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4294 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4295 Libgcrypt Reference Manual}).
4298 @cindex authorizing, archives
4299 Authorize imports signed by the public key passed on standard input.
4300 The public key must be in ``s-expression advanced format''---i.e., the
4301 same format as the @file{signing-key.pub} file.
4303 The list of authorized keys is kept in the human-editable file
4304 @file{/etc/guix/acl}. The file contains
4305 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4306 s-expressions''} and is structured as an access-control list in the
4307 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4310 @item --extract=@var{directory}
4311 @itemx -x @var{directory}
4312 Read a single-item archive as served by substitute servers
4313 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4314 low-level operation needed in only very narrow use cases; see below.
4316 For example, the following command extracts the substitute for Emacs
4317 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4321 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-emacs-24.5 \
4322 | bunzip2 | guix archive -x /tmp/emacs
4325 Single-item archives are different from multiple-item archives produced
4326 by @command{guix archive --export}; they contain a single store item,
4327 and they do @emph{not} embed a signature. Thus this operation does
4328 @emph{no} signature verification and its output should be considered
4331 The primary purpose of this operation is to facilitate inspection of
4332 archive contents coming from possibly untrusted substitute servers.
4337 @c *********************************************************************
4339 @chapter Development
4341 @cindex software development
4342 If you are a software developer, Guix provides tools that you should find
4343 helpful---independently of the language you're developing in. This is what
4344 this chapter is about.
4346 The @command{guix environment} command provides a convenient way to set up
4347 @dfn{development environments} containing all the dependencies and tools
4348 necessary to work on the software package of your choice. The @command{guix
4349 pack} command allows you to create @dfn{application bundles} that can be
4350 easily distributed to users who do not run Guix.
4353 * Invoking guix environment:: Setting up development environments.
4354 * Invoking guix pack:: Creating software bundles.
4357 @node Invoking guix environment
4358 @section Invoking @command{guix environment}
4360 @cindex reproducible build environments
4361 @cindex development environments
4362 @cindex @command{guix environment}
4363 @cindex environment, package build environment
4364 The purpose of @command{guix environment} is to assist hackers in
4365 creating reproducible development environments without polluting their
4366 package profile. The @command{guix environment} tool takes one or more
4367 packages, builds all of their inputs, and creates a shell
4368 environment to use them.
4370 The general syntax is:
4373 guix environment @var{options} @var{package}@dots{}
4376 The following example spawns a new shell set up for the development of
4380 guix environment guile
4383 If the needed dependencies are not built yet, @command{guix environment}
4384 automatically builds them. The environment of the new shell is an augmented
4385 version of the environment that @command{guix environment} was run in.
4386 It contains the necessary search paths for building the given package
4387 added to the existing environment variables. To create a ``pure''
4388 environment, in which the original environment variables have been unset,
4389 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4390 environment variables such as @code{PATH} in their @file{~/.bashrc}
4391 file. As a consequence, when @code{guix environment} launches it, Bash
4392 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4393 environment variables. It is an error to define such environment
4394 variables in @file{.bashrc}; instead, they should be defined in
4395 @file{.bash_profile}, which is sourced only by log-in shells.
4396 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4397 details on Bash start-up files.}.
4399 @vindex GUIX_ENVIRONMENT
4400 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4401 variable in the shell it spawns; its value is the file name of the
4402 profile of this environment. This allows users to, say, define a
4403 specific prompt for development environments in their @file{.bashrc}
4404 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4407 if [ -n "$GUIX_ENVIRONMENT" ]
4409 export PS1="\u@@\h \w [dev]\$ "
4414 ...@: or to browse the profile:
4417 $ ls "$GUIX_ENVIRONMENT/bin"
4420 Additionally, more than one package may be specified, in which case the
4421 union of the inputs for the given packages are used. For example, the
4422 command below spawns a shell where all of the dependencies of both Guile
4423 and Emacs are available:
4426 guix environment guile emacs
4429 Sometimes an interactive shell session is not desired. An arbitrary
4430 command may be invoked by placing the @code{--} token to separate the
4431 command from the rest of the arguments:
4434 guix environment guile -- make -j4
4437 In other situations, it is more convenient to specify the list of
4438 packages needed in the environment. For example, the following command
4439 runs @command{python} from an environment containing Python@tie{}2.7 and
4443 guix environment --ad-hoc python2-numpy python-2.7 -- python
4446 Furthermore, one might want the dependencies of a package and also some
4447 additional packages that are not build-time or runtime dependencies, but
4448 are useful when developing nonetheless. Because of this, the
4449 @code{--ad-hoc} flag is positional. Packages appearing before
4450 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4451 added to the environment. Packages appearing after are interpreted as
4452 packages that will be added to the environment directly. For example,
4453 the following command creates a Guix development environment that
4454 additionally includes Git and strace:
4457 guix environment guix --ad-hoc git strace
4460 Sometimes it is desirable to isolate the environment as much as
4461 possible, for maximal purity and reproducibility. In particular, when
4462 using Guix on a host distro that is not Guix System, it is desirable to
4463 prevent access to @file{/usr/bin} and other system-wide resources from
4464 the development environment. For example, the following command spawns
4465 a Guile REPL in a ``container'' where only the store and the current
4466 working directory are mounted:
4469 guix environment --ad-hoc --container guile -- guile
4473 The @code{--container} option requires Linux-libre 3.19 or newer.
4476 The available options are summarized below.
4479 @item --root=@var{file}
4480 @itemx -r @var{file}
4481 @cindex persistent environment
4482 @cindex garbage collector root, for environments
4483 Make @var{file} a symlink to the profile for this environment, and
4484 register it as a garbage collector root.
4486 This is useful if you want to protect your environment from garbage
4487 collection, to make it ``persistent''.
4489 When this option is omitted, the environment is protected from garbage
4490 collection only for the duration of the @command{guix environment}
4491 session. This means that next time you recreate the same environment,
4492 you could have to rebuild or re-download packages. @xref{Invoking guix
4493 gc}, for more on GC roots.
4495 @item --expression=@var{expr}
4496 @itemx -e @var{expr}
4497 Create an environment for the package or list of packages that
4498 @var{expr} evaluates to.
4500 For example, running:
4503 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4506 starts a shell with the environment for this specific variant of the
4512 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4515 starts a shell with all the base system packages available.
4517 The above commands only use the default output of the given packages.
4518 To select other outputs, two element tuples can be specified:
4521 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4524 @item --load=@var{file}
4525 @itemx -l @var{file}
4526 Create an environment for the package or list of packages that the code
4527 within @var{file} evaluates to.
4529 As an example, @var{file} might contain a definition like this
4530 (@pxref{Defining Packages}):
4533 @verbatiminclude environment-gdb.scm
4536 @item --manifest=@var{file}
4537 @itemx -m @var{file}
4538 Create an environment for the packages contained in the manifest object
4539 returned by the Scheme code in @var{file}.
4541 This is similar to the same-named option in @command{guix package}
4542 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4546 Include all specified packages in the resulting environment, as if an
4547 @i{ad hoc} package were defined with them as inputs. This option is
4548 useful for quickly creating an environment without having to write a
4549 package expression to contain the desired inputs.
4551 For instance, the command:
4554 guix environment --ad-hoc guile guile-sdl -- guile
4557 runs @command{guile} in an environment where Guile and Guile-SDL are
4560 Note that this example implicitly asks for the default output of
4561 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4562 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4563 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4565 This option may be composed with the default behavior of @command{guix
4566 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4567 as packages whose dependencies will be added to the environment, the
4568 default behavior. Packages appearing after are interpreted as packages
4569 that will be added to the environment directly.
4572 Unset existing environment variables when building the new environment, except
4573 those specified with @option{--preserve} (see below.) This has the effect of
4574 creating an environment in which search paths only contain package inputs.
4576 @item --preserve=@var{regexp}
4577 @itemx -E @var{regexp}
4578 When used alongside @option{--pure}, preserve the environment variables
4579 matching @var{regexp}---in other words, put them on a ``white list'' of
4580 environment variables that must be preserved. This option can be repeated
4584 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4588 This example runs @command{mpirun} in a context where the only environment
4589 variables defined are @code{PATH}, environment variables whose name starts
4590 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4593 @item --search-paths
4594 Display the environment variable definitions that make up the
4597 @item --system=@var{system}
4598 @itemx -s @var{system}
4599 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4604 Run @var{command} within an isolated container. The current working
4605 directory outside the container is mapped inside the container.
4606 Additionally, unless overridden with @code{--user}, a dummy home
4607 directory is created that matches the current user's home directory, and
4608 @file{/etc/passwd} is configured accordingly.
4610 The spawned process runs as the current user outside the container. Inside
4611 the container, it has the same UID and GID as the current user, unless
4612 @option{--user} is passed (see below.)
4616 For containers, share the network namespace with the host system.
4617 Containers created without this flag only have access to the loopback
4620 @item --link-profile
4622 For containers, link the environment profile to
4623 @file{~/.guix-profile} within the container. This is equivalent to
4624 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4625 within the container. Linking will fail and abort the environment if
4626 the directory already exists, which will certainly be the case if
4627 @command{guix environment} was invoked in the user's home directory.
4629 Certain packages are configured to look in
4630 @code{~/.guix-profile} for configuration files and data;@footnote{For
4631 example, the @code{fontconfig} package inspects
4632 @file{~/.guix-profile/share/fonts} for additional fonts.}
4633 @code{--link-profile} allows these programs to behave as expected within
4636 @item --user=@var{user}
4637 @itemx -u @var{user}
4638 For containers, use the username @var{user} in place of the current
4639 user. The generated @file{/etc/passwd} entry within the container will
4640 contain the name @var{user}, the home directory will be
4641 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4642 the UID and GID inside the container are 1000. @var{user}
4643 need not exist on the system.
4645 Additionally, any shared or exposed path (see @code{--share} and
4646 @code{--expose} respectively) whose target is within the current user's
4647 home directory will be remapped relative to @file{/home/USER}; this
4648 includes the automatic mapping of the current working directory.
4651 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4653 guix environment --container --user=foo \
4654 --expose=$HOME/test \
4655 --expose=/tmp/target=$HOME/target
4658 While this will limit the leaking of user identity through home paths
4659 and each of the user fields, this is only one useful component of a
4660 broader privacy/anonymity solution---not one in and of itself.
4662 @item --expose=@var{source}[=@var{target}]
4663 For containers, expose the file system @var{source} from the host system
4664 as the read-only file system @var{target} within the container. If
4665 @var{target} is not specified, @var{source} is used as the target mount
4666 point in the container.
4668 The example below spawns a Guile REPL in a container in which the user's
4669 home directory is accessible read-only via the @file{/exchange}
4673 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
4676 @item --share=@var{source}[=@var{target}]
4677 For containers, share the file system @var{source} from the host system
4678 as the writable file system @var{target} within the container. If
4679 @var{target} is not specified, @var{source} is used as the target mount
4680 point in the container.
4682 The example below spawns a Guile REPL in a container in which the user's
4683 home directory is accessible for both reading and writing via the
4684 @file{/exchange} directory:
4687 guix environment --container --share=$HOME=/exchange --ad-hoc guile -- guile
4691 @command{guix environment}
4692 also supports all of the common build options that @command{guix
4693 build} supports (@pxref{Common Build Options}) as well as package
4694 transformation options (@pxref{Package Transformation Options}).
4696 @node Invoking guix pack
4697 @section Invoking @command{guix pack}
4699 Occasionally you want to pass software to people who are not (yet!)
4700 lucky enough to be using Guix. You'd tell them to run @command{guix
4701 package -i @var{something}}, but that's not possible in this case. This
4702 is where @command{guix pack} comes in.
4705 If you are looking for ways to exchange binaries among machines that
4706 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
4707 publish}, and @ref{Invoking guix archive}.
4712 @cindex application bundle
4713 @cindex software bundle
4714 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
4715 @dfn{software bundle}: it creates a tarball or some other archive
4716 containing the binaries of the software you're interested in, and all
4717 its dependencies. The resulting archive can be used on any machine that
4718 does not have Guix, and people can run the exact same binaries as those
4719 you have with Guix. The pack itself is created in a bit-reproducible
4720 fashion, so anyone can verify that it really contains the build results
4721 that you pretend to be shipping.
4723 For example, to create a bundle containing Guile, Emacs, Geiser, and all
4724 their dependencies, you can run:
4727 $ guix pack guile emacs geiser
4729 /gnu/store/@dots{}-pack.tar.gz
4732 The result here is a tarball containing a @file{/gnu/store} directory
4733 with all the relevant packages. The resulting tarball contains a
4734 @dfn{profile} with the three packages of interest; the profile is the
4735 same as would be created by @command{guix package -i}. It is this
4736 mechanism that is used to create Guix's own standalone binary tarball
4737 (@pxref{Binary Installation}).
4739 Users of this pack would have to run
4740 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
4741 find inconvenient. To work around it, you can create, say, a
4742 @file{/opt/gnu/bin} symlink to the profile:
4745 guix pack -S /opt/gnu/bin=bin guile emacs geiser
4749 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
4751 @cindex relocatable binaries, with @command{guix pack}
4752 What if the recipient of your pack does not have root privileges on
4753 their machine, and thus cannot unpack it in the root file system? In
4754 that case, you will want to use the @code{--relocatable} option (see
4755 below). This option produces @dfn{relocatable binaries}, meaning they
4756 they can be placed anywhere in the file system hierarchy: in the example
4757 above, users can unpack your tarball in their home directory and
4758 directly run @file{./opt/gnu/bin/guile}.
4760 @cindex Docker, build an image with guix pack
4761 Alternatively, you can produce a pack in the Docker image format using
4762 the following command:
4765 guix pack -f docker guile emacs geiser
4769 The result is a tarball that can be passed to the @command{docker load}
4771 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
4772 documentation} for more information.
4774 @cindex Singularity, build an image with guix pack
4775 @cindex SquashFS, build an image with guix pack
4776 Yet another option is to produce a SquashFS image with the following
4780 guix pack -f squashfs guile emacs geiser
4784 The result is a SquashFS file system image that can either be mounted or
4785 directly be used as a file system container image with the
4786 @uref{https://singularity.lbl.gov, Singularity container execution
4787 environment}, using commands like @command{singularity shell} or
4788 @command{singularity exec}.
4790 Several command-line options allow you to customize your pack:
4793 @item --format=@var{format}
4794 @itemx -f @var{format}
4795 Produce a pack in the given @var{format}.
4797 The available formats are:
4801 This is the default format. It produces a tarball containing all the
4802 specified binaries and symlinks.
4805 This produces a tarball that follows the
4806 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
4807 Docker Image Specification}.
4810 This produces a SquashFS image containing all the specified binaries and
4811 symlinks, as well as empty mount points for virtual file systems like
4815 @cindex relocatable binaries
4818 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
4819 anywhere in the file system hierarchy and run from there.
4821 When this option is passed once, the resulting binaries require support for
4822 @dfn{user namespaces} in the kernel Linux; when passed
4823 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
4824 PRoot support, can be thought of as the abbreviation of ``Really
4825 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
4826 if user namespaces are unavailable, and essentially work anywhere---see below
4827 for the implications.
4829 For example, if you create a pack containing Bash with:
4832 guix pack -RR -S /mybin=bin bash
4836 ...@: you can copy that pack to a machine that lacks Guix, and from your
4837 home directory as a normal user, run:
4845 In that shell, if you type @code{ls /gnu/store}, you'll notice that
4846 @file{/gnu/store} shows up and contains all the dependencies of
4847 @code{bash}, even though the machine actually lacks @file{/gnu/store}
4848 altogether! That is probably the simplest way to deploy Guix-built
4849 software on a non-Guix machine.
4852 By default, relocatable binaries rely on the @dfn{user namespace} feature of
4853 the kernel Linux, which allows unprivileged users to mount or change root.
4854 Old versions of Linux did not support it, and some GNU/Linux distributions
4857 To produce relocatable binaries that work even in the absence of user
4858 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
4859 case, binaries will try user namespace support and fall back to PRoot if user
4860 namespaces are not supported.
4862 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
4863 support for file system virtualization. It achieves that by using the
4864 @code{ptrace} system call on the running program. This approach has the
4865 advantage to work without requiring special kernel support, but it incurs
4866 run-time overhead every time a system call is made.
4869 @item --expression=@var{expr}
4870 @itemx -e @var{expr}
4871 Consider the package @var{expr} evaluates to.
4873 This has the same purpose as the same-named option in @command{guix
4874 build} (@pxref{Additional Build Options, @code{--expression} in
4875 @command{guix build}}).
4877 @item --manifest=@var{file}
4878 @itemx -m @var{file}
4879 Use the packages contained in the manifest object returned by the Scheme
4882 This has a similar purpose as the same-named option in @command{guix
4883 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
4884 same manifest files. It allows you to define a collection of packages
4885 once and use it both for creating profiles and for creating archives
4886 for use on machines that do not have Guix installed. Note that you can
4887 specify @emph{either} a manifest file @emph{or} a list of packages,
4890 @item --system=@var{system}
4891 @itemx -s @var{system}
4892 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4893 the system type of the build host.
4895 @item --target=@var{triplet}
4896 @cindex cross-compilation
4897 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
4898 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
4899 configuration triplets,, autoconf, Autoconf}).
4901 @item --compression=@var{tool}
4902 @itemx -C @var{tool}
4903 Compress the resulting tarball using @var{tool}---one of @code{gzip},
4904 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
4906 @item --symlink=@var{spec}
4907 @itemx -S @var{spec}
4908 Add the symlinks specified by @var{spec} to the pack. This option can
4909 appear several times.
4911 @var{spec} has the form @code{@var{source}=@var{target}}, where
4912 @var{source} is the symlink that will be created and @var{target} is the
4915 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
4916 symlink pointing to the @file{bin} sub-directory of the profile.
4918 @item --save-provenance
4919 Save provenance information for the packages passed on the command line.
4920 Provenance information includes the URL and commit of the channels in use
4923 Provenance information is saved in the
4924 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
4925 usual package metadata---the name and version of each package, their
4926 propagated inputs, and so on. It is useful information to the recipient of
4927 the pack, who then knows how the pack was (supposedly) obtained.
4929 This option is not enabled by default because, like timestamps, provenance
4930 information contributes nothing to the build process. In other words, there
4931 is an infinity of channel URLs and commit IDs that can lead to the same pack.
4932 Recording such ``silent'' metadata in the output thus potentially breaks the
4933 source-to-binary bitwise reproducibility property.
4935 @item --root=@var{file}
4936 @itemx -r @var{file}
4937 @cindex garbage collector root, for packs
4938 Make @var{file} a symlink to the resulting pack, and register it as a garbage
4941 @item --localstatedir
4942 @itemx --profile-name=@var{name}
4943 Include the ``local state directory'', @file{/var/guix}, in the resulting
4944 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
4945 profile---by default @var{name} is @code{guix-profile}, which corresponds to
4946 @file{~root/.guix-profile}.
4948 @file{/var/guix} contains the store database (@pxref{The Store}) as well
4949 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
4950 the pack means that the store is ``complete'' and manageable by Guix;
4951 not providing it pack means that the store is ``dead'': items cannot be
4952 added to it or removed from it after extraction of the pack.
4954 One use case for this is the Guix self-contained binary tarball
4955 (@pxref{Binary Installation}).
4958 Use the bootstrap binaries to build the pack. This option is only
4959 useful to Guix developers.
4962 In addition, @command{guix pack} supports all the common build options
4963 (@pxref{Common Build Options}) and all the package transformation
4964 options (@pxref{Package Transformation Options}).
4967 @c *********************************************************************
4968 @node Programming Interface
4969 @chapter Programming Interface
4971 GNU Guix provides several Scheme programming interfaces (APIs) to
4972 define, build, and query packages. The first interface allows users to
4973 write high-level package definitions. These definitions refer to
4974 familiar packaging concepts, such as the name and version of a package,
4975 its build system, and its dependencies. These definitions can then be
4976 turned into concrete build actions.
4978 Build actions are performed by the Guix daemon, on behalf of users. In a
4979 standard setup, the daemon has write access to the store---the
4980 @file{/gnu/store} directory---whereas users do not. The recommended
4981 setup also has the daemon perform builds in chroots, under a specific
4982 build users, to minimize interference with the rest of the system.
4985 Lower-level APIs are available to interact with the daemon and the
4986 store. To instruct the daemon to perform a build action, users actually
4987 provide it with a @dfn{derivation}. A derivation is a low-level
4988 representation of the build actions to be taken, and the environment in
4989 which they should occur---derivations are to package definitions what
4990 assembly is to C programs. The term ``derivation'' comes from the fact
4991 that build results @emph{derive} from them.
4993 This chapter describes all these APIs in turn, starting from high-level
4994 package definitions.
4997 * Package Modules:: Packages from the programmer's viewpoint.
4998 * Defining Packages:: Defining new packages.
4999 * Build Systems:: Specifying how packages are built.
5000 * The Store:: Manipulating the package store.
5001 * Derivations:: Low-level interface to package derivations.
5002 * The Store Monad:: Purely functional interface to the store.
5003 * G-Expressions:: Manipulating build expressions.
5004 * Invoking guix repl:: Fiddling with Guix interactively.
5007 @node Package Modules
5008 @section Package Modules
5010 From a programming viewpoint, the package definitions of the
5011 GNU distribution are provided by Guile modules in the @code{(gnu packages
5012 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5013 packages @dots{})} module name space are not necessarily ``GNU
5014 packages''. This module naming scheme follows the usual Guile module
5015 naming convention: @code{gnu} means that these modules are distributed
5016 as part of the GNU system, and @code{packages} identifies modules that
5017 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5018 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5019 module exports a variable named @code{emacs}, which is bound to a
5020 @code{<package>} object (@pxref{Defining Packages}).
5022 The @code{(gnu packages @dots{})} module name space is
5023 automatically scanned for packages by the command-line tools. For
5024 instance, when running @code{guix install emacs}, all the @code{(gnu
5025 packages @dots{})} modules are scanned until one that exports a package
5026 object whose name is @code{emacs} is found. This package search
5027 facility is implemented in the @code{(gnu packages)} module.
5029 @cindex customization, of packages
5030 @cindex package module search path
5031 Users can store package definitions in modules with different
5032 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5033 name and module name must match. For instance, the @code{(my-packages
5034 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5035 relative to the load path specified with @option{--load-path} or
5036 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5037 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5038 these package definitions visible to the user interfaces:
5042 By adding the directory containing your package modules to the search path
5043 with the @code{-L} flag of @command{guix package} and other commands
5044 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5045 environment variable described below.
5048 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5049 pulls from it. A channel is essentially a Git repository containing package
5050 modules. @xref{Channels}, for more information on how to define and use
5054 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5056 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5057 This is a colon-separated list of directories to search for additional
5058 package modules. Directories listed in this variable take precedence
5059 over the own modules of the distribution.
5062 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5063 each package is built based solely on other packages in the
5064 distribution. The root of this dependency graph is a small set of
5065 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5066 bootstrap)} module. For more information on bootstrapping,
5067 @pxref{Bootstrapping}.
5069 @node Defining Packages
5070 @section Defining Packages
5072 The high-level interface to package definitions is implemented in the
5073 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5074 example, the package definition, or @dfn{recipe}, for the GNU Hello
5075 package looks like this:
5078 (define-module (gnu packages hello)
5079 #:use-module (guix packages)
5080 #:use-module (guix download)
5081 #:use-module (guix build-system gnu)
5082 #:use-module (guix licenses)
5083 #:use-module (gnu packages gawk))
5085 (define-public hello
5091 (uri (string-append "mirror://gnu/hello/hello-" version
5095 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5096 (build-system gnu-build-system)
5097 (arguments '(#:configure-flags '("--enable-silent-rules")))
5098 (inputs `(("gawk" ,gawk)))
5099 (synopsis "Hello, GNU world: An example GNU package")
5100 (description "Guess what GNU Hello prints!")
5101 (home-page "https://www.gnu.org/software/hello/")
5106 Without being a Scheme expert, the reader may have guessed the meaning
5107 of the various fields here. This expression binds the variable
5108 @code{hello} to a @code{<package>} object, which is essentially a record
5109 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5110 This package object can be inspected using procedures found in the
5111 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5112 returns---surprise!---@code{"hello"}.
5114 With luck, you may be able to import part or all of the definition of
5115 the package you are interested in from another repository, using the
5116 @code{guix import} command (@pxref{Invoking guix import}).
5118 In the example above, @var{hello} is defined in a module of its own,
5119 @code{(gnu packages hello)}. Technically, this is not strictly
5120 necessary, but it is convenient to do so: all the packages defined in
5121 modules under @code{(gnu packages @dots{})} are automatically known to
5122 the command-line tools (@pxref{Package Modules}).
5124 There are a few points worth noting in the above package definition:
5128 The @code{source} field of the package is an @code{<origin>} object
5129 (@pxref{origin Reference}, for the complete reference).
5130 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5131 meaning that the source is a file to be downloaded over FTP or HTTP.
5133 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5134 the GNU mirrors defined in @code{(guix download)}.
5136 The @code{sha256} field specifies the expected SHA256 hash of the file
5137 being downloaded. It is mandatory, and allows Guix to check the
5138 integrity of the file. The @code{(base32 @dots{})} form introduces the
5139 base32 representation of the hash. You can obtain this information with
5140 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5141 hash} (@pxref{Invoking guix hash}).
5144 When needed, the @code{origin} form can also have a @code{patches} field
5145 listing patches to be applied, and a @code{snippet} field giving a
5146 Scheme expression to modify the source code.
5149 @cindex GNU Build System
5150 The @code{build-system} field specifies the procedure to build the
5151 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5152 represents the familiar GNU Build System, where packages may be
5153 configured, built, and installed with the usual @code{./configure &&
5154 make && make check && make install} command sequence.
5157 The @code{arguments} field specifies options for the build system
5158 (@pxref{Build Systems}). Here it is interpreted by
5159 @var{gnu-build-system} as a request run @file{configure} with the
5160 @code{--enable-silent-rules} flag.
5166 What about these quote (@code{'}) characters? They are Scheme syntax to
5167 introduce a literal list; @code{'} is synonymous with @code{quote}.
5168 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5169 for details. Here the value of the @code{arguments} field is a list of
5170 arguments passed to the build system down the road, as with @code{apply}
5171 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5174 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5175 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5176 @code{#:configure-flags} is a keyword used to pass a keyword argument
5177 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5181 The @code{inputs} field specifies inputs to the build process---i.e.,
5182 build-time or run-time dependencies of the package. Here, we define an
5183 input called @code{"gawk"} whose value is that of the @var{gawk}
5184 variable; @var{gawk} is itself bound to a @code{<package>} object.
5186 @cindex backquote (quasiquote)
5189 @cindex comma (unquote)
5193 @findex unquote-splicing
5194 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5195 us to introduce a literal list in the @code{inputs} field, while
5196 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5197 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5200 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5201 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5202 of ensuring that they are present (@pxref{Build Systems}).
5204 However, any other dependencies need to be specified in the
5205 @code{inputs} field. Any dependency not specified here will simply be
5206 unavailable to the build process, possibly leading to a build failure.
5209 @xref{package Reference}, for a full description of possible fields.
5211 Once a package definition is in place, the
5212 package may actually be built using the @code{guix build} command-line
5213 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5214 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5215 package definition using the @command{guix edit} command
5216 (@pxref{Invoking guix edit}).
5217 @xref{Packaging Guidelines}, for
5218 more information on how to test package definitions, and
5219 @ref{Invoking guix lint}, for information on how to check a definition
5220 for style conformance.
5221 @vindex GUIX_PACKAGE_PATH
5222 Lastly, @pxref{Channels}, for information
5223 on how to extend the distribution by adding your own package definitions
5226 Finally, updating the package definition to a new upstream version
5227 can be partly automated by the @command{guix refresh} command
5228 (@pxref{Invoking guix refresh}).
5230 Behind the scenes, a derivation corresponding to the @code{<package>}
5231 object is first computed by the @code{package-derivation} procedure.
5232 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5233 The build actions it prescribes may then be realized by using the
5234 @code{build-derivations} procedure (@pxref{The Store}).
5236 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5237 Return the @code{<derivation>} object of @var{package} for @var{system}
5238 (@pxref{Derivations}).
5240 @var{package} must be a valid @code{<package>} object, and @var{system}
5241 must be a string denoting the target system type---e.g.,
5242 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5243 must be a connection to the daemon, which operates on the store
5244 (@pxref{The Store}).
5248 @cindex cross-compilation
5249 Similarly, it is possible to compute a derivation that cross-builds a
5250 package for some other system:
5252 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5253 @var{package} @var{target} [@var{system}]
5254 Return the @code{<derivation>} object of @var{package} cross-built from
5255 @var{system} to @var{target}.
5257 @var{target} must be a valid GNU triplet denoting the target hardware
5258 and operating system, such as @code{"mips64el-linux-gnu"}
5259 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5262 @cindex package transformations
5263 @cindex input rewriting
5264 @cindex dependency tree rewriting
5265 Packages can be manipulated in arbitrary ways. An example of a useful
5266 transformation is @dfn{input rewriting}, whereby the dependency tree of
5267 a package is rewritten by replacing specific inputs by others:
5269 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5270 [@var{rewrite-name}]
5271 Return a procedure that, when passed a package, replaces its direct and
5272 indirect dependencies (but not its implicit inputs) according to
5273 @var{replacements}. @var{replacements} is a list of package pairs; the
5274 first element of each pair is the package to replace, and the second one
5277 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5278 the name of a package and returns its new name after rewrite.
5282 Consider this example:
5285 (define libressl-instead-of-openssl
5286 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5288 (package-input-rewriting `((,openssl . ,libressl))))
5290 (define git-with-libressl
5291 (libressl-instead-of-openssl git))
5295 Here we first define a rewriting procedure that replaces @var{openssl}
5296 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5297 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5298 This is exactly what the @option{--with-input} command-line option does
5299 (@pxref{Package Transformation Options, @option{--with-input}}).
5301 The following variant of @code{package-input-rewriting} can match packages to
5302 be replaced by name rather than by identity.
5304 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5305 Return a procedure that, given a package, applies the given @var{replacements} to
5306 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5307 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5308 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5309 replacement for that package.
5312 The example above could be rewritten this way:
5315 (define libressl-instead-of-openssl
5316 ;; Replace all the packages called "openssl" with LibreSSL.
5317 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5320 The key difference here is that, this time, packages are matched by spec and
5321 not by identity. In other words, any package in the graph that is called
5322 @code{openssl} will be replaced.
5324 A more generic procedure to rewrite a package dependency graph is
5325 @code{package-mapping}: it supports arbitrary changes to nodes in the
5328 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5329 Return a procedure that, given a package, applies @var{proc} to all the packages
5330 depended on and returns the resulting package. The procedure stops recursion
5331 when @var{cut?} returns true for a given package.
5335 * package Reference:: The package data type.
5336 * origin Reference:: The origin data type.
5340 @node package Reference
5341 @subsection @code{package} Reference
5343 This section summarizes all the options available in @code{package}
5344 declarations (@pxref{Defining Packages}).
5346 @deftp {Data Type} package
5347 This is the data type representing a package recipe.
5351 The name of the package, as a string.
5353 @item @code{version}
5354 The version of the package, as a string.
5357 An object telling how the source code for the package should be
5358 acquired. Most of the time, this is an @code{origin} object, which
5359 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5360 can also be any other ``file-like'' object such as a @code{local-file},
5361 which denotes a file from the local file system (@pxref{G-Expressions,
5362 @code{local-file}}).
5364 @item @code{build-system}
5365 The build system that should be used to build the package (@pxref{Build
5368 @item @code{arguments} (default: @code{'()})
5369 The arguments that should be passed to the build system. This is a
5370 list, typically containing sequential keyword-value pairs.
5372 @item @code{inputs} (default: @code{'()})
5373 @itemx @code{native-inputs} (default: @code{'()})
5374 @itemx @code{propagated-inputs} (default: @code{'()})
5375 @cindex inputs, of packages
5376 These fields list dependencies of the package. Each one is a list of
5377 tuples, where each tuple has a label for the input (a string) as its
5378 first element, a package, origin, or derivation as its second element,
5379 and optionally the name of the output thereof that should be used, which
5380 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5381 more on package outputs). For example, the list below specifies three
5385 `(("libffi" ,libffi)
5386 ("libunistring" ,libunistring)
5387 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5390 @cindex cross compilation, package dependencies
5391 The distinction between @code{native-inputs} and @code{inputs} is
5392 necessary when considering cross-compilation. When cross-compiling,
5393 dependencies listed in @code{inputs} are built for the @emph{target}
5394 architecture; conversely, dependencies listed in @code{native-inputs}
5395 are built for the architecture of the @emph{build} machine.
5397 @code{native-inputs} is typically used to list tools needed at
5398 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5399 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5400 this area (@pxref{Invoking guix lint}).
5402 @anchor{package-propagated-inputs}
5403 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5404 specified packages will be automatically installed alongside the package
5405 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5406 package}}, for information on how @command{guix package} deals with
5409 For example this is necessary when a C/C++ library needs headers of
5410 another library to compile, or when a pkg-config file refers to another
5411 one @i{via} its @code{Requires} field.
5413 Another example where @code{propagated-inputs} is useful is for languages
5414 that lack a facility to record the run-time search path akin to the
5415 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5416 more. To ensure that libraries written in those languages can find
5417 library code they depend on at run time, run-time dependencies must be
5418 listed in @code{propagated-inputs} rather than @code{inputs}.
5420 @item @code{outputs} (default: @code{'("out")})
5421 The list of output names of the package. @xref{Packages with Multiple
5422 Outputs}, for typical uses of additional outputs.
5424 @item @code{native-search-paths} (default: @code{'()})
5425 @itemx @code{search-paths} (default: @code{'()})
5426 A list of @code{search-path-specification} objects describing
5427 search-path environment variables honored by the package.
5429 @item @code{replacement} (default: @code{#f})
5430 This must be either @code{#f} or a package object that will be used as a
5431 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5434 @item @code{synopsis}
5435 A one-line description of the package.
5437 @item @code{description}
5438 A more elaborate description of the package.
5440 @item @code{license}
5441 @cindex license, of packages
5442 The license of the package; a value from @code{(guix licenses)},
5443 or a list of such values.
5445 @item @code{home-page}
5446 The URL to the home-page of the package, as a string.
5448 @item @code{supported-systems} (default: @var{%supported-systems})
5449 The list of systems supported by the package, as strings of the form
5450 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5452 @item @code{maintainers} (default: @code{'()})
5453 The list of maintainers of the package, as @code{maintainer} objects.
5455 @item @code{location} (default: source location of the @code{package} form)
5456 The source location of the package. It is useful to override this when
5457 inheriting from another package, in which case this field is not
5458 automatically corrected.
5462 @deffn {Scheme Syntax} this-package
5463 When used in the @emph{lexical scope} of a package field definition, this
5464 identifier resolves to the package being defined.
5466 The example below shows how to add a package as a native input of itself when
5474 ;; When cross-compiled, Guile, for example, depends on
5475 ;; a native version of itself. Add it here.
5476 (native-inputs (if (%current-target-system)
5477 `(("self" ,this-package))
5481 It is an error to refer to @code{this-package} outside a package definition.
5484 @node origin Reference
5485 @subsection @code{origin} Reference
5487 This section summarizes all the options available in @code{origin}
5488 declarations (@pxref{Defining Packages}).
5490 @deftp {Data Type} origin
5491 This is the data type representing a source code origin.
5495 An object containing the URI of the source. The object type depends on
5496 the @code{method} (see below). For example, when using the
5497 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5498 values are: a URL represented as a string, or a list thereof.
5501 A procedure that handles the URI.
5506 @item @var{url-fetch} from @code{(guix download)}
5507 download a file from the HTTP, HTTPS, or FTP URL specified in the
5511 @item @var{git-fetch} from @code{(guix git-download)}
5512 clone the Git version control repository, and check out the revision
5513 specified in the @code{uri} field as a @code{git-reference} object; a
5514 @code{git-reference} looks like this:
5518 (url "git://git.debian.org/git/pkg-shadow/shadow")
5519 (commit "v4.1.5.1"))
5524 A bytevector containing the SHA-256 hash of the source. Typically the
5525 @code{base32} form is used here to generate the bytevector from a
5528 You can obtain this information using @code{guix download}
5529 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5532 @item @code{file-name} (default: @code{#f})
5533 The file name under which the source code should be saved. When this is
5534 @code{#f}, a sensible default value will be used in most cases. In case
5535 the source is fetched from a URL, the file name from the URL will be
5536 used. For version control checkouts, it is recommended to provide the
5537 file name explicitly because the default is not very descriptive.
5539 @item @code{patches} (default: @code{'()})
5540 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5541 file-like objects}) pointing to patches to be applied to the source.
5543 This list of patches must be unconditional. In particular, it cannot
5544 depend on the value of @code{%current-system} or
5545 @code{%current-target-system}.
5547 @item @code{snippet} (default: @code{#f})
5548 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5549 in the source directory. This is a convenient way to modify the source,
5550 sometimes more convenient than a patch.
5552 @item @code{patch-flags} (default: @code{'("-p1")})
5553 A list of command-line flags that should be passed to the @code{patch}
5556 @item @code{patch-inputs} (default: @code{#f})
5557 Input packages or derivations to the patching process. When this is
5558 @code{#f}, the usual set of inputs necessary for patching are provided,
5559 such as GNU@tie{}Patch.
5561 @item @code{modules} (default: @code{'()})
5562 A list of Guile modules that should be loaded during the patching
5563 process and while running the code in the @code{snippet} field.
5565 @item @code{patch-guile} (default: @code{#f})
5566 The Guile package that should be used in the patching process. When
5567 this is @code{#f}, a sensible default is used.
5573 @section Build Systems
5575 @cindex build system
5576 Each package definition specifies a @dfn{build system} and arguments for
5577 that build system (@pxref{Defining Packages}). This @code{build-system}
5578 field represents the build procedure of the package, as well as implicit
5579 dependencies of that build procedure.
5581 Build systems are @code{<build-system>} objects. The interface to
5582 create and manipulate them is provided by the @code{(guix build-system)}
5583 module, and actual build systems are exported by specific modules.
5585 @cindex bag (low-level package representation)
5586 Under the hood, build systems first compile package objects to
5587 @dfn{bags}. A @dfn{bag} is like a package, but with less
5588 ornamentation---in other words, a bag is a lower-level representation of
5589 a package, which includes all the inputs of that package, including some
5590 that were implicitly added by the build system. This intermediate
5591 representation is then compiled to a derivation (@pxref{Derivations}).
5593 Build systems accept an optional list of @dfn{arguments}. In package
5594 definitions, these are passed @i{via} the @code{arguments} field
5595 (@pxref{Defining Packages}). They are typically keyword arguments
5596 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5597 Guile Reference Manual}). The value of these arguments is usually
5598 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5599 by the daemon (@pxref{Derivations}).
5601 The main build system is @var{gnu-build-system}, which implements the
5602 standard build procedure for GNU and many other packages. It
5603 is provided by the @code{(guix build-system gnu)} module.
5605 @defvr {Scheme Variable} gnu-build-system
5606 @var{gnu-build-system} represents the GNU Build System, and variants
5607 thereof (@pxref{Configuration, configuration and makefile conventions,,
5608 standards, GNU Coding Standards}).
5610 @cindex build phases
5611 In a nutshell, packages using it are configured, built, and installed with
5612 the usual @code{./configure && make && make check && make install}
5613 command sequence. In practice, a few additional steps are often needed.
5614 All these steps are split up in separate @dfn{phases},
5615 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5616 modules for more details about the build phases.}:
5620 Unpack the source tarball, and change the current directory to the
5621 extracted source tree. If the source is actually a directory, copy it
5622 to the build tree, and enter that directory.
5624 @item patch-source-shebangs
5625 Patch shebangs encountered in source files so they refer to the right
5626 store file names. For instance, this changes @code{#!/bin/sh} to
5627 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
5630 Run the @file{configure} script with a number of default options, such
5631 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
5632 by the @code{#:configure-flags} argument.
5635 Run @code{make} with the list of flags specified with
5636 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
5637 (the default), build with @code{make -j}.
5640 Run @code{make check}, or some other target specified with
5641 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
5642 @code{#:parallel-tests?} argument is true (the default), run @code{make
5646 Run @code{make install} with the flags listed in @code{#:make-flags}.
5648 @item patch-shebangs
5649 Patch shebangs on the installed executable files.
5652 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
5653 is false), copying them to the @code{debug} output when available
5654 (@pxref{Installing Debugging Files}).
5657 @vindex %standard-phases
5658 The build-side module @code{(guix build gnu-build-system)} defines
5659 @var{%standard-phases} as the default list of build phases.
5660 @var{%standard-phases} is a list of symbol/procedure pairs, where the
5661 procedure implements the actual phase.
5663 The list of phases used for a particular package can be changed with the
5664 @code{#:phases} parameter. For instance, passing:
5667 #:phases (modify-phases %standard-phases (delete 'configure))
5670 means that all the phases described above will be used, except the
5671 @code{configure} phase.
5673 In addition, this build system ensures that the ``standard'' environment
5674 for GNU packages is available. This includes tools such as GCC, libc,
5675 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
5676 build-system gnu)} module for a complete list). We call these the
5677 @dfn{implicit inputs} of a package, because package definitions do not
5678 have to mention them.
5681 Other @code{<build-system>} objects are defined to support other
5682 conventions and tools used by free software packages. They inherit most
5683 of @var{gnu-build-system}, and differ mainly in the set of inputs
5684 implicitly added to the build process, and in the list of phases
5685 executed. Some of these build systems are listed below.
5687 @defvr {Scheme Variable} ant-build-system
5688 This variable is exported by @code{(guix build-system ant)}. It
5689 implements the build procedure for Java packages that can be built with
5690 @url{https://ant.apache.org/, Ant build tool}.
5692 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
5693 provided by the @code{icedtea} package to the set of inputs. Different
5694 packages can be specified with the @code{#:ant} and @code{#:jdk}
5695 parameters, respectively.
5697 When the original package does not provide a suitable Ant build file,
5698 the parameter @code{#:jar-name} can be used to generate a minimal Ant
5699 build file @file{build.xml} with tasks to build the specified jar
5700 archive. In this case the parameter @code{#:source-dir} can be used to
5701 specify the source sub-directory, defaulting to ``src''.
5703 The @code{#:main-class} parameter can be used with the minimal ant
5704 buildfile to specify the main class of the resulting jar. This makes the
5705 jar file executable. The @code{#:test-include} parameter can be used to
5706 specify the list of junit tests to run. It defaults to
5707 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
5708 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
5709 because abstract classes cannot be run as tests.
5711 The parameter @code{#:build-target} can be used to specify the Ant task
5712 that should be run during the @code{build} phase. By default the
5713 ``jar'' task will be run.
5717 @defvr {Scheme Variable} android-ndk-build-system
5718 @cindex Android distribution
5719 @cindex Android NDK build system
5720 This variable is exported by @code{(guix build-system android-ndk)}. It
5721 implements a build procedure for Android NDK (native development kit)
5722 packages using a Guix-specific build process.
5724 The build system assumes that packages install their public interface
5725 (header) files to the subdirectory "include" of the "out" output and
5726 their libraries to the subdirectory "lib" of the "out" output.
5728 It's also assumed that the union of all the dependencies of a package
5729 has no conflicting files.
5731 For the time being, cross-compilation is not supported - so right now
5732 the libraries and header files are assumed to be host tools.
5736 @defvr {Scheme Variable} asdf-build-system/source
5737 @defvrx {Scheme Variable} asdf-build-system/sbcl
5738 @defvrx {Scheme Variable} asdf-build-system/ecl
5740 These variables, exported by @code{(guix build-system asdf)}, implement
5741 build procedures for Common Lisp packages using
5742 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
5743 definition facility for Common Lisp programs and libraries.
5745 The @code{asdf-build-system/source} system installs the packages in
5746 source form, and can be loaded using any common lisp implementation, via
5747 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
5748 systems in the format which a particular implementation understands.
5749 These build systems can also be used to produce executable programs, or
5750 lisp images which contain a set of packages pre-loaded.
5752 The build system uses naming conventions. For binary packages, the
5753 package name should be prefixed with the lisp implementation, such as
5754 @code{sbcl-} for @code{asdf-build-system/sbcl}.
5756 Additionally, the corresponding source package should be labeled using
5757 the same convention as python packages (see @ref{Python Modules}), using
5758 the @code{cl-} prefix.
5760 For binary packages, each system should be defined as a Guix package.
5761 If one package @code{origin} contains several systems, package variants
5762 can be created in order to build all the systems. Source packages,
5763 which use @code{asdf-build-system/source}, may contain several systems.
5765 In order to create executable programs and images, the build-side
5766 procedures @code{build-program} and @code{build-image} can be used.
5767 They should be called in a build phase after the @code{create-symlinks}
5768 phase, so that the system which was just built can be used within the
5769 resulting image. @code{build-program} requires a list of Common Lisp
5770 expressions to be passed as the @code{#:entry-program} argument.
5772 If the system is not defined within its own @code{.asd} file of the same
5773 name, then the @code{#:asd-file} parameter should be used to specify
5774 which file the system is defined in. Furthermore, if the package
5775 defines a system for its tests in a separate file, it will be loaded
5776 before the tests are run if it is specified by the
5777 @code{#:test-asd-file} parameter. If it is not set, the files
5778 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
5779 and @code{test.asd} will be tried if they exist.
5781 If for some reason the package must be named in a different way than the
5782 naming conventions suggest, the @code{#:asd-system-name} parameter can
5783 be used to specify the name of the system.
5787 @defvr {Scheme Variable} cargo-build-system
5788 @cindex Rust programming language
5789 @cindex Cargo (Rust build system)
5790 This variable is exported by @code{(guix build-system cargo)}. It
5791 supports builds of packages using Cargo, the build tool of the
5792 @uref{https://www.rust-lang.org, Rust programming language}.
5794 In its @code{configure} phase, this build system replaces dependencies
5795 specified in the @file{Cargo.toml} file with inputs to the Guix package.
5796 The @code{install} phase installs the binaries, and it also installs the
5797 source code and @file{Cargo.toml} file.
5800 @cindex Clojure (programming language)
5801 @cindex simple Clojure build system
5802 @defvr {Scheme Variable} clojure-build-system
5803 This variable is exported by @code{(guix build-system clojure)}. It implements
5804 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
5805 using plain old @code{compile} in Clojure. Cross-compilation is not supported
5808 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
5809 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
5810 @code{#:zip} parameters, respectively.
5812 A list of source directories, test directories and jar names can be specified
5813 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
5814 parameters, respectively. Compile directory and main class can be specified
5815 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
5816 Other parameters are documented below.
5818 This build system is an extension of @var{ant-build-system}, but with the
5819 following phases changed:
5824 This phase calls @code{compile} in Clojure to compile source files and runs
5825 @command{jar} to create jars from both source files and compiled files
5826 according to the include list and exclude list specified in
5827 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
5828 has priority over the include list. These lists consist of symbols
5829 representing Clojure libraries or the special keyword @code{#:all} representing
5830 all Clojure libraries found under the source directories. The parameter
5831 @code{#:omit-source?} decides if source should be included into the jars.
5834 This phase runs tests according to the include list and exclude list specified
5835 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
5836 meanings are analogous to that of @code{#:aot-include} and
5837 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
5838 stands for all Clojure libraries found under the test directories. The
5839 parameter @code{#:tests?} decides if tests should be run.
5842 This phase installs all jars built previously.
5845 Apart from the above, this build system also contains an additional phase:
5850 This phase installs all top-level files with base name matching
5851 @var{%doc-regex}. A different regex can be specified with the
5852 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
5853 directories specified in @code{#:doc-dirs} are installed as well.
5857 @defvr {Scheme Variable} cmake-build-system
5858 This variable is exported by @code{(guix build-system cmake)}. It
5859 implements the build procedure for packages using the
5860 @url{https://www.cmake.org, CMake build tool}.
5862 It automatically adds the @code{cmake} package to the set of inputs.
5863 Which package is used can be specified with the @code{#:cmake}
5866 The @code{#:configure-flags} parameter is taken as a list of flags
5867 passed to the @command{cmake} command. The @code{#:build-type}
5868 parameter specifies in abstract terms the flags passed to the compiler;
5869 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
5870 debugging information''), which roughly means that code is compiled with
5871 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
5874 @defvr {Scheme Variable} dune-build-system
5875 This variable is exported by @code{(guix build-system dune)}. It
5876 supports builds of packages using @uref{https://dune.build/, Dune}, a build
5877 tool for the OCaml programming language. It is implemented as an extension
5878 of the @code{ocaml-build-system} which is described below. As such, the
5879 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
5882 It automatically adds the @code{dune} package to the set of inputs.
5883 Which package is used can be specified with the @code{#:dune}
5886 There is no @code{configure} phase because dune packages typically don't
5887 need to be configured. The @code{#:build-flags} parameter is taken as a
5888 list of flags passed to the @code{dune} command during the build.
5890 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
5891 command instead of the more recent @code{dune} command while building
5892 a package. Its default value is @code{#f}.
5894 The @code{#:package} parameter can be passed to specify a package name, which
5895 is useful when a package contains multiple packages and you want to build
5896 only one of them. This is equivalent to passing the @code{-p} argument to
5900 @defvr {Scheme Variable} go-build-system
5901 This variable is exported by @code{(guix build-system go)}. It
5902 implements a build procedure for Go packages using the standard
5903 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
5904 Go build mechanisms}.
5906 The user is expected to provide a value for the key @code{#:import-path}
5907 and, in some cases, @code{#:unpack-path}. The
5908 @url{https://golang.org/doc/code.html#ImportPaths, import path}
5909 corresponds to the file system path expected by the package's build
5910 scripts and any referring packages, and provides a unique way to
5911 refer to a Go package. It is typically based on a combination of the
5912 package source code's remote URI and file system hierarchy structure. In
5913 some cases, you will need to unpack the package's source code to a
5914 different directory structure than the one indicated by the import path,
5915 and @code{#:unpack-path} should be used in such cases.
5917 Packages that provide Go libraries should install their source code into
5918 the built output. The key @code{#:install-source?}, which defaults to
5919 @code{#t}, controls whether or not the source code is installed. It can
5920 be set to @code{#f} for packages that only provide executable files.
5923 @defvr {Scheme Variable} glib-or-gtk-build-system
5924 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
5925 is intended for use with packages making use of GLib or GTK+.
5927 This build system adds the following two phases to the ones defined by
5928 @var{gnu-build-system}:
5931 @item glib-or-gtk-wrap
5932 The phase @code{glib-or-gtk-wrap} ensures that programs in
5933 @file{bin/} are able to find GLib ``schemas'' and
5934 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
5935 modules}. This is achieved by wrapping the programs in launch scripts
5936 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
5937 environment variables.
5939 It is possible to exclude specific package outputs from that wrapping
5940 process by listing their names in the
5941 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
5942 when an output is known not to contain any GLib or GTK+ binaries, and
5943 where wrapping would gratuitously add a dependency of that output on
5946 @item glib-or-gtk-compile-schemas
5947 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
5948 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
5949 GSettings schemas} of GLib are compiled. Compilation is performed by the
5950 @command{glib-compile-schemas} program. It is provided by the package
5951 @code{glib:bin} which is automatically imported by the build system.
5952 The @code{glib} package providing @command{glib-compile-schemas} can be
5953 specified with the @code{#:glib} parameter.
5956 Both phases are executed after the @code{install} phase.
5959 @defvr {Scheme Variable} guile-build-system
5960 This build system is for Guile packages that consist exclusively of Scheme
5961 code and that are so lean that they don't even have a makefile, let alone a
5962 @file{configure} script. It compiles Scheme code using @command{guild
5963 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
5964 installs the @file{.scm} and @file{.go} files in the right place. It also
5965 installs documentation.
5967 This build system supports cross-compilation by using the @code{--target}
5968 option of @command{guild compile}.
5970 Packages built with @code{guile-build-system} must provide a Guile package in
5971 their @code{native-inputs} field.
5974 @defvr {Scheme Variable} minify-build-system
5975 This variable is exported by @code{(guix build-system minify)}. It
5976 implements a minification procedure for simple JavaScript packages.
5978 It adds @code{uglify-js} to the set of inputs and uses it to compress
5979 all JavaScript files in the @file{src} directory. A different minifier
5980 package can be specified with the @code{#:uglify-js} parameter, but it
5981 is expected that the package writes the minified code to the standard
5984 When the input JavaScript files are not all located in the @file{src}
5985 directory, the parameter @code{#:javascript-files} can be used to
5986 specify a list of file names to feed to the minifier.
5989 @defvr {Scheme Variable} ocaml-build-system
5990 This variable is exported by @code{(guix build-system ocaml)}. It implements
5991 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
5992 of choosing the correct set of commands to run for each package. OCaml
5993 packages can expect many different commands to be run. This build system will
5996 When the package has a @file{setup.ml} file present at the top-level, it will
5997 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
5998 @code{ocaml setup.ml -install}. The build system will assume that this file
5999 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6000 care of setting the prefix and enabling tests if they are not disabled. You
6001 can pass configure and build flags with the @code{#:configure-flags} and
6002 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6003 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6004 bypass this system in the build and install phases.
6006 When the package has a @file{configure} file, it is assumed that it is a
6007 hand-made configure script that requires a different argument format than
6008 in the @code{gnu-build-system}. You can add more flags with the
6009 @code{#:configure-flags} key.
6011 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6012 @code{#t}), it will be used and more flags can be passed to the build and
6013 install phases with the @code{#:make-flags} key.
6015 Finally, some packages do not have these files and use a somewhat standard
6016 location for its build system. In that case, the build system will run
6017 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6018 providing the path to the required findlib module. Additional flags can
6019 be passed via the @code{#:build-flags} key. Install is taken care of by
6020 @command{opam-installer}. In this case, the @code{opam} package must
6021 be added to the @code{native-inputs} field of the package definition.
6023 Note that most OCaml packages assume they will be installed in the same
6024 directory as OCaml, which is not what we want in guix. In particular, they
6025 will install @file{.so} files in their module's directory, which is usually
6026 fine because it is in the OCaml compiler directory. In guix though, these
6027 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6028 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6029 @file{.so} libraries should be installed.
6032 @defvr {Scheme Variable} python-build-system
6033 This variable is exported by @code{(guix build-system python)}. It
6034 implements the more or less standard build procedure used by Python
6035 packages, which consists in running @code{python setup.py build} and
6036 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6038 For packages that install stand-alone Python programs under @code{bin/},
6039 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6040 environment variable points to all the Python libraries they depend on.
6042 Which Python package is used to perform the build can be specified with
6043 the @code{#:python} parameter. This is a useful way to force a package
6044 to be built for a specific version of the Python interpreter, which
6045 might be necessary if the package is only compatible with a single
6046 interpreter version.
6048 By default guix calls @code{setup.py} under control of
6049 @code{setuptools}, much like @command{pip} does. Some packages are not
6050 compatible with setuptools (and pip), thus you can disable this by
6051 setting the @code{#:use-setuptools} parameter to @code{#f}.
6054 @defvr {Scheme Variable} perl-build-system
6055 This variable is exported by @code{(guix build-system perl)}. It
6056 implements the standard build procedure for Perl packages, which either
6057 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6058 followed by @code{Build} and @code{Build install}; or in running
6059 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6060 @code{make} and @code{make install}, depending on which of
6061 @code{Build.PL} or @code{Makefile.PL} is present in the package
6062 distribution. Preference is given to the former if both @code{Build.PL}
6063 and @code{Makefile.PL} exist in the package distribution. This
6064 preference can be reversed by specifying @code{#t} for the
6065 @code{#:make-maker?} parameter.
6067 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6068 passes flags specified by the @code{#:make-maker-flags} or
6069 @code{#:module-build-flags} parameter, respectively.
6071 Which Perl package is used can be specified with @code{#:perl}.
6074 @defvr {Scheme Variable} r-build-system
6075 This variable is exported by @code{(guix build-system r)}. It
6076 implements the build procedure used by @uref{https://r-project.org, R}
6077 packages, which essentially is little more than running @code{R CMD
6078 INSTALL --library=/gnu/store/@dots{}} in an environment where
6079 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6080 are run after installation using the R function
6081 @code{tools::testInstalledPackage}.
6084 @defvr {Scheme Variable} rakudo-build-system
6085 This variable is exported by @code{(guix build-system rakudo)}. It
6086 implements the build procedure used by @uref{https://rakudo.org/,
6087 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6088 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6089 installs the binaries, library files and the resources, as well as wrap
6090 the files under the @code{bin/} directory. Tests can be skipped by
6091 passing @code{#f} to the @code{tests?} parameter.
6093 Which rakudo package is used can be specified with @code{rakudo}.
6094 Which perl6-tap-harness package used for the tests can be specified with
6095 @code{#:prove6} or removed by passing @code{#f} to the
6096 @code{with-prove6?} parameter.
6097 Which perl6-zef package used for tests and installing can be specified
6098 with @code{#:zef} or removed by passing @code{#f} to the
6099 @code{with-zef?} parameter.
6102 @defvr {Scheme Variable} texlive-build-system
6103 This variable is exported by @code{(guix build-system texlive)}. It is
6104 used to build TeX packages in batch mode with a specified engine. The
6105 build system sets the @code{TEXINPUTS} variable to find all TeX source
6106 files in the inputs.
6108 By default it runs @code{luatex} on all files ending on @code{ins}. A
6109 different engine and format can be specified with the
6110 @code{#:tex-format} argument. Different build targets can be specified
6111 with the @code{#:build-targets} argument, which expects a list of file
6112 names. The build system adds only @code{texlive-bin} and
6113 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6114 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6115 and @code{#:texlive-latex-base}, respectively.
6117 The @code{#:tex-directory} parameter tells the build system where to
6118 install the built files under the texmf tree.
6121 @defvr {Scheme Variable} ruby-build-system
6122 This variable is exported by @code{(guix build-system ruby)}. It
6123 implements the RubyGems build procedure used by Ruby packages, which
6124 involves running @code{gem build} followed by @code{gem install}.
6126 The @code{source} field of a package that uses this build system
6127 typically references a gem archive, since this is the format that Ruby
6128 developers use when releasing their software. The build system unpacks
6129 the gem archive, potentially patches the source, runs the test suite,
6130 repackages the gem, and installs it. Additionally, directories and
6131 tarballs may be referenced to allow building unreleased gems from Git or
6132 a traditional source release tarball.
6134 Which Ruby package is used can be specified with the @code{#:ruby}
6135 parameter. A list of additional flags to be passed to the @command{gem}
6136 command can be specified with the @code{#:gem-flags} parameter.
6139 @defvr {Scheme Variable} waf-build-system
6140 This variable is exported by @code{(guix build-system waf)}. It
6141 implements a build procedure around the @code{waf} script. The common
6142 phases---@code{configure}, @code{build}, and @code{install}---are
6143 implemented by passing their names as arguments to the @code{waf}
6146 The @code{waf} script is executed by the Python interpreter. Which
6147 Python package is used to run the script can be specified with the
6148 @code{#:python} parameter.
6151 @defvr {Scheme Variable} scons-build-system
6152 This variable is exported by @code{(guix build-system scons)}. It
6153 implements the build procedure used by the SCons software construction
6154 tool. This build system runs @code{scons} to build the package,
6155 @code{scons test} to run tests, and then @code{scons install} to install
6158 Additional flags to be passed to @code{scons} can be specified with the
6159 @code{#:scons-flags} parameter. The version of Python used to run SCons
6160 can be specified by selecting the appropriate SCons package with the
6161 @code{#:scons} parameter.
6164 @defvr {Scheme Variable} haskell-build-system
6165 This variable is exported by @code{(guix build-system haskell)}. It
6166 implements the Cabal build procedure used by Haskell packages, which
6167 involves running @code{runhaskell Setup.hs configure
6168 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6169 Instead of installing the package by running @code{runhaskell Setup.hs
6170 install}, to avoid trying to register libraries in the read-only
6171 compiler store directory, the build system uses @code{runhaskell
6172 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6173 addition, the build system generates the package documentation by
6174 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6175 is passed. Optional Haddock parameters can be passed with the help of
6176 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6177 not found, the build system looks for @code{Setup.lhs} instead.
6179 Which Haskell compiler is used can be specified with the @code{#:haskell}
6180 parameter which defaults to @code{ghc}.
6183 @defvr {Scheme Variable} dub-build-system
6184 This variable is exported by @code{(guix build-system dub)}. It
6185 implements the Dub build procedure used by D packages, which
6186 involves running @code{dub build} and @code{dub run}.
6187 Installation is done by copying the files manually.
6189 Which D compiler is used can be specified with the @code{#:ldc}
6190 parameter which defaults to @code{ldc}.
6193 @defvr {Scheme Variable} emacs-build-system
6194 This variable is exported by @code{(guix build-system emacs)}. It
6195 implements an installation procedure similar to the packaging system
6196 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6198 It first creates the @code{@var{package}-autoloads.el} file, then it
6199 byte compiles all Emacs Lisp files. Differently from the Emacs
6200 packaging system, the Info documentation files are moved to the standard
6201 documentation directory and the @file{dir} file is deleted. Each
6202 package is installed in its own directory under
6203 @file{share/emacs/site-lisp/guix.d}.
6206 @defvr {Scheme Variable} font-build-system
6207 This variable is exported by @code{(guix build-system font)}. It
6208 implements an installation procedure for font packages where upstream
6209 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6210 need to be copied into place. It copies font files to standard
6211 locations in the output directory.
6214 @defvr {Scheme Variable} meson-build-system
6215 This variable is exported by @code{(guix build-system meson)}. It
6216 implements the build procedure for packages that use
6217 @url{https://mesonbuild.com, Meson} as their build system.
6219 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6220 of inputs, and they can be changed with the parameters @code{#:meson}
6221 and @code{#:ninja} if needed. The default Meson is
6222 @code{meson-for-build}, which is special because it doesn't clear the
6223 @code{RUNPATH} of binaries and libraries when they are installed.
6225 This build system is an extension of @var{gnu-build-system}, but with the
6226 following phases changed to some specific for Meson:
6231 The phase runs @code{meson} with the flags specified in
6232 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6233 @code{plain} unless something else is specified in @code{#:build-type}.
6236 The phase runs @code{ninja} to build the package in parallel by default, but
6237 this can be changed with @code{#:parallel-build?}.
6240 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6241 which is @code{"test"} by default.
6244 The phase runs @code{ninja install} and can not be changed.
6247 Apart from that, the build system also adds the following phases:
6252 This phase ensures that all binaries can find the libraries they need.
6253 It searches for required libraries in subdirectories of the package being
6254 built, and adds those to @code{RUNPATH} where needed. It also removes
6255 references to libraries left over from the build phase by
6256 @code{meson-for-build}, such as test dependencies, that aren't actually
6257 required for the program to run.
6259 @item glib-or-gtk-wrap
6260 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6261 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6263 @item glib-or-gtk-compile-schemas
6264 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6265 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6269 @defvr {Scheme Variable} linux-module-build-system
6270 @var{linux-module-build-system} allows building Linux kernel modules.
6272 @cindex build phases
6273 This build system is an extension of @var{gnu-build-system}, but with the
6274 following phases changed:
6279 This phase configures the environment so that the Linux kernel's Makefile
6280 can be used to build the external kernel module.
6283 This phase uses the Linux kernel's Makefile in order to build the external
6287 This phase uses the Linux kernel's Makefile in order to install the external
6291 It is possible and useful to specify the Linux kernel to use for building
6292 the module (in the "arguments" form of a package using the
6293 linux-module-build-system, use the key #:linux to specify it).
6296 Lastly, for packages that do not need anything as sophisticated, a
6297 ``trivial'' build system is provided. It is trivial in the sense that
6298 it provides basically no support: it does not pull any implicit inputs,
6299 and does not have a notion of build phases.
6301 @defvr {Scheme Variable} trivial-build-system
6302 This variable is exported by @code{(guix build-system trivial)}.
6304 This build system requires a @code{#:builder} argument. This argument
6305 must be a Scheme expression that builds the package output(s)---as
6306 with @code{build-expression->derivation} (@pxref{Derivations,
6307 @code{build-expression->derivation}}).
6317 Conceptually, the @dfn{store} is the place where derivations that have
6318 been built successfully are stored---by default, @file{/gnu/store}.
6319 Sub-directories in the store are referred to as @dfn{store items} or
6320 sometimes @dfn{store paths}. The store has an associated database that
6321 contains information such as the store paths referred to by each store
6322 path, and the list of @emph{valid} store items---results of successful
6323 builds. This database resides in @file{@var{localstatedir}/guix/db},
6324 where @var{localstatedir} is the state directory specified @i{via}
6325 @option{--localstatedir} at configure time, usually @file{/var}.
6327 The store is @emph{always} accessed by the daemon on behalf of its clients
6328 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6329 connect to the daemon over a Unix-domain socket, send requests to it,
6330 and read the result---these are remote procedure calls, or RPCs.
6333 Users must @emph{never} modify files under @file{/gnu/store} directly.
6334 This would lead to inconsistencies and break the immutability
6335 assumptions of Guix's functional model (@pxref{Introduction}).
6337 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6338 how to check the integrity of the store and attempt recovery from
6339 accidental modifications.
6342 The @code{(guix store)} module provides procedures to connect to the
6343 daemon, and to perform RPCs. These are described below. By default,
6344 @code{open-connection}, and thus all the @command{guix} commands,
6345 connect to the local daemon or to the URI specified by the
6346 @code{GUIX_DAEMON_SOCKET} environment variable.
6348 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6349 When set, the value of this variable should be a file name or a URI
6350 designating the daemon endpoint. When it is a file name, it denotes a
6351 Unix-domain socket to connect to. In addition to file names, the
6352 supported URI schemes are:
6357 These are for Unix-domain sockets.
6358 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6359 @file{/var/guix/daemon-socket/socket}.
6362 @cindex daemon, remote access
6363 @cindex remote access to the daemon
6364 @cindex daemon, cluster setup
6365 @cindex clusters, daemon setup
6366 These URIs denote connections over TCP/IP, without encryption nor
6367 authentication of the remote host. The URI must specify the host name
6368 and optionally a port number (by default port 44146 is used):
6371 guix://master.guix.example.org:1234
6374 This setup is suitable on local networks, such as clusters, where only
6375 trusted nodes may connect to the build daemon at
6376 @code{master.guix.example.org}.
6378 The @code{--listen} option of @command{guix-daemon} can be used to
6379 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6383 @cindex SSH access to build daemons
6384 These URIs allow you to connect to a remote daemon over
6385 SSH@footnote{This feature requires Guile-SSH (@pxref{Requirements}).}.
6386 A typical URL might look like this:
6389 ssh://charlie@@guix.example.org:22
6392 As for @command{guix copy}, the usual OpenSSH client configuration files
6393 are honored (@pxref{Invoking guix copy}).
6396 Additional URI schemes may be supported in the future.
6398 @c XXX: Remove this note when the protocol incurs fewer round trips
6399 @c and when (guix derivations) no longer relies on file system access.
6401 The ability to connect to remote build daemons is considered
6402 experimental as of @value{VERSION}. Please get in touch with us to
6403 share any problems or suggestions you may have (@pxref{Contributing}).
6407 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6408 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6409 @var{reserve-space?} is true, instruct it to reserve a little bit of
6410 extra space on the file system so that the garbage collector can still
6411 operate should the disk become full. Return a server object.
6413 @var{file} defaults to @var{%default-socket-path}, which is the normal
6414 location given the options that were passed to @command{configure}.
6417 @deffn {Scheme Procedure} close-connection @var{server}
6418 Close the connection to @var{server}.
6421 @defvr {Scheme Variable} current-build-output-port
6422 This variable is bound to a SRFI-39 parameter, which refers to the port
6423 where build and error logs sent by the daemon should be written.
6426 Procedures that make RPCs all take a server object as their first
6429 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6430 @cindex invalid store items
6431 Return @code{#t} when @var{path} designates a valid store item and
6432 @code{#f} otherwise (an invalid item may exist on disk but still be
6433 invalid, for instance because it is the result of an aborted or failed
6436 A @code{&store-protocol-error} condition is raised if @var{path} is not
6437 prefixed by the store directory (@file{/gnu/store}).
6440 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6441 Add @var{text} under file @var{name} in the store, and return its store
6442 path. @var{references} is the list of store paths referred to by the
6443 resulting store path.
6446 @deffn {Scheme Procedure} build-derivations @var{server} @var{derivations}
6447 Build @var{derivations} (a list of @code{<derivation>} objects or
6448 derivation paths), and return when the worker is done building them.
6449 Return @code{#t} on success.
6452 Note that the @code{(guix monads)} module provides a monad as well as
6453 monadic versions of the above procedures, with the goal of making it
6454 more convenient to work with code that accesses the store (@pxref{The
6458 @i{This section is currently incomplete.}
6461 @section Derivations
6464 Low-level build actions and the environment in which they are performed
6465 are represented by @dfn{derivations}. A derivation contains the
6466 following pieces of information:
6470 The outputs of the derivation---derivations produce at least one file or
6471 directory in the store, but may produce more.
6474 @cindex build-time dependencies
6475 @cindex dependencies, build-time
6476 The inputs of the derivations---i.e., its build-time dependencies---which may
6477 be other derivations or plain files in the store (patches, build scripts,
6481 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
6484 The file name of a build script in the store, along with the arguments
6488 A list of environment variables to be defined.
6492 @cindex derivation path
6493 Derivations allow clients of the daemon to communicate build actions to
6494 the store. They exist in two forms: as an in-memory representation,
6495 both on the client- and daemon-side, and as files in the store whose
6496 name end in @code{.drv}---these files are referred to as @dfn{derivation
6497 paths}. Derivations paths can be passed to the @code{build-derivations}
6498 procedure to perform the build actions they prescribe (@pxref{The
6501 @cindex fixed-output derivations
6502 Operations such as file downloads and version-control checkouts for
6503 which the expected content hash is known in advance are modeled as
6504 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
6505 of a fixed-output derivation are independent of its inputs---e.g., a
6506 source code download produces the same result regardless of the download
6507 method and tools being used.
6510 @cindex run-time dependencies
6511 @cindex dependencies, run-time
6512 The outputs of derivations---i.e., the build results---have a set of
6513 @dfn{references}, as reported by the @code{references} RPC or the
6514 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
6515 are the set of run-time dependencies of the build results. References are a
6516 subset of the inputs of the derivation; this subset is automatically computed
6517 by the build daemon by scanning all the files in the outputs.
6519 The @code{(guix derivations)} module provides a representation of
6520 derivations as Scheme objects, along with procedures to create and
6521 otherwise manipulate derivations. The lowest-level primitive to create
6522 a derivation is the @code{derivation} procedure:
6524 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
6525 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6526 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
6527 [#:system (%current-system)] [#:references-graphs #f] @
6528 [#:allowed-references #f] [#:disallowed-references #f] @
6529 [#:leaked-env-vars #f] [#:local-build? #f] @
6530 [#:substitutable? #t] [#:properties '()]
6531 Build a derivation with the given arguments, and return the resulting
6532 @code{<derivation>} object.
6534 When @var{hash} and @var{hash-algo} are given, a
6535 @dfn{fixed-output derivation} is created---i.e., one whose result is
6536 known in advance, such as a file download. If, in addition,
6537 @var{recursive?} is true, then that fixed output may be an executable
6538 file or a directory and @var{hash} must be the hash of an archive
6539 containing this output.
6541 When @var{references-graphs} is true, it must be a list of file
6542 name/store path pairs. In that case, the reference graph of each store
6543 path is exported in the build environment in the corresponding file, in
6544 a simple text format.
6546 When @var{allowed-references} is true, it must be a list of store items
6547 or outputs that the derivation's output may refer to. Likewise,
6548 @var{disallowed-references}, if true, must be a list of things the
6549 outputs may @emph{not} refer to.
6551 When @var{leaked-env-vars} is true, it must be a list of strings
6552 denoting environment variables that are allowed to ``leak'' from the
6553 daemon's environment to the build environment. This is only applicable
6554 to fixed-output derivations---i.e., when @var{hash} is true. The main
6555 use is to allow variables such as @code{http_proxy} to be passed to
6556 derivations that download files.
6558 When @var{local-build?} is true, declare that the derivation is not a
6559 good candidate for offloading and should rather be built locally
6560 (@pxref{Daemon Offload Setup}). This is the case for small derivations
6561 where the costs of data transfers would outweigh the benefits.
6563 When @var{substitutable?} is false, declare that substitutes of the
6564 derivation's output should not be used (@pxref{Substitutes}). This is
6565 useful, for instance, when building packages that capture details of the
6566 host CPU instruction set.
6568 @var{properties} must be an association list describing ``properties'' of the
6569 derivation. It is kept as-is, uninterpreted, in the derivation.
6573 Here's an example with a shell script as its builder, assuming
6574 @var{store} is an open connection to the daemon, and @var{bash} points
6575 to a Bash executable in the store:
6578 (use-modules (guix utils)
6582 (let ((builder ; add the Bash script to the store
6583 (add-text-to-store store "my-builder.sh"
6584 "echo hello world > $out\n" '())))
6585 (derivation store "foo"
6586 bash `("-e" ,builder)
6587 #:inputs `((,bash) (,builder))
6588 #:env-vars '(("HOME" . "/homeless"))))
6589 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
6592 As can be guessed, this primitive is cumbersome to use directly. A
6593 better approach is to write build scripts in Scheme, of course! The
6594 best course of action for that is to write the build code as a
6595 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
6596 information, @pxref{G-Expressions}.
6598 Once upon a time, @code{gexp->derivation} did not exist and constructing
6599 derivations with build code written in Scheme was achieved with
6600 @code{build-expression->derivation}, documented below. This procedure
6601 is now deprecated in favor of the much nicer @code{gexp->derivation}.
6603 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
6604 @var{name} @var{exp} @
6605 [#:system (%current-system)] [#:inputs '()] @
6606 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6607 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
6608 [#:references-graphs #f] [#:allowed-references #f] @
6609 [#:disallowed-references #f] @
6610 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
6611 Return a derivation that executes Scheme expression @var{exp} as a
6612 builder for derivation @var{name}. @var{inputs} must be a list of
6613 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
6614 @code{"out"} is assumed. @var{modules} is a list of names of Guile
6615 modules from the current search path to be copied in the store,
6616 compiled, and made available in the load path during the execution of
6617 @var{exp}---e.g., @code{((guix build utils) (guix build
6618 gnu-build-system))}.
6620 @var{exp} is evaluated in an environment where @code{%outputs} is bound
6621 to a list of output/path pairs, and where @code{%build-inputs} is bound
6622 to a list of string/output-path pairs made from @var{inputs}.
6623 Optionally, @var{env-vars} is a list of string pairs specifying the name
6624 and value of environment variables visible to the builder. The builder
6625 terminates by passing the result of @var{exp} to @code{exit}; thus, when
6626 @var{exp} returns @code{#f}, the build is considered to have failed.
6628 @var{exp} is built using @var{guile-for-build} (a derivation). When
6629 @var{guile-for-build} is omitted or is @code{#f}, the value of the
6630 @code{%guile-for-build} fluid is used instead.
6632 See the @code{derivation} procedure for the meaning of
6633 @var{references-graphs}, @var{allowed-references},
6634 @var{disallowed-references}, @var{local-build?}, and
6635 @var{substitutable?}.
6639 Here's an example of a single-output derivation that creates a directory
6640 containing one file:
6643 (let ((builder '(let ((out (assoc-ref %outputs "out")))
6644 (mkdir out) ; create /gnu/store/@dots{}-goo
6645 (call-with-output-file (string-append out "/test")
6647 (display '(hello guix) p))))))
6648 (build-expression->derivation store "goo" builder))
6650 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
6654 @node The Store Monad
6655 @section The Store Monad
6659 The procedures that operate on the store described in the previous
6660 sections all take an open connection to the build daemon as their first
6661 argument. Although the underlying model is functional, they either have
6662 side effects or depend on the current state of the store.
6664 The former is inconvenient: the connection to the build daemon has to be
6665 carried around in all those functions, making it impossible to compose
6666 functions that do not take that parameter with functions that do. The
6667 latter can be problematic: since store operations have side effects
6668 and/or depend on external state, they have to be properly sequenced.
6670 @cindex monadic values
6671 @cindex monadic functions
6672 This is where the @code{(guix monads)} module comes in. This module
6673 provides a framework for working with @dfn{monads}, and a particularly
6674 useful monad for our uses, the @dfn{store monad}. Monads are a
6675 construct that allows two things: associating ``context'' with values
6676 (in our case, the context is the store), and building sequences of
6677 computations (here computations include accesses to the store). Values
6678 in a monad---values that carry this additional context---are called
6679 @dfn{monadic values}; procedures that return such values are called
6680 @dfn{monadic procedures}.
6682 Consider this ``normal'' procedure:
6685 (define (sh-symlink store)
6686 ;; Return a derivation that symlinks the 'bash' executable.
6687 (let* ((drv (package-derivation store bash))
6688 (out (derivation->output-path drv))
6689 (sh (string-append out "/bin/bash")))
6690 (build-expression->derivation store "sh"
6691 `(symlink ,sh %output))))
6694 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
6695 as a monadic function:
6698 (define (sh-symlink)
6699 ;; Same, but return a monadic value.
6700 (mlet %store-monad ((drv (package->derivation bash)))
6701 (gexp->derivation "sh"
6702 #~(symlink (string-append #$drv "/bin/bash")
6706 There are several things to note in the second version: the @code{store}
6707 parameter is now implicit and is ``threaded'' in the calls to the
6708 @code{package->derivation} and @code{gexp->derivation} monadic
6709 procedures, and the monadic value returned by @code{package->derivation}
6710 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
6712 As it turns out, the call to @code{package->derivation} can even be
6713 omitted since it will take place implicitly, as we will see later
6714 (@pxref{G-Expressions}):
6717 (define (sh-symlink)
6718 (gexp->derivation "sh"
6719 #~(symlink (string-append #$bash "/bin/bash")
6724 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
6725 @c for the funny quote.
6726 Calling the monadic @code{sh-symlink} has no effect. As someone once
6727 said, ``you exit a monad like you exit a building on fire: by running''.
6728 So, to exit the monad and get the desired effect, one must use
6729 @code{run-with-store}:
6732 (run-with-store (open-connection) (sh-symlink))
6733 @result{} /gnu/store/...-sh-symlink
6736 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
6737 new ``meta-commands'' to make it easier to deal with monadic procedures:
6738 @code{run-in-store}, and @code{enter-store-monad}. The former is used
6739 to ``run'' a single monadic value through the store:
6742 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
6743 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6746 The latter enters a recursive REPL, where all the return values are
6747 automatically run through the store:
6750 scheme@@(guile-user)> ,enter-store-monad
6751 store-monad@@(guile-user) [1]> (package->derivation hello)
6752 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6753 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
6754 $3 = "/gnu/store/@dots{}-foo"
6755 store-monad@@(guile-user) [1]> ,q
6756 scheme@@(guile-user)>
6760 Note that non-monadic values cannot be returned in the
6761 @code{store-monad} REPL.
6763 The main syntactic forms to deal with monads in general are provided by
6764 the @code{(guix monads)} module and are described below.
6766 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
6767 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
6771 @deffn {Scheme Syntax} return @var{val}
6772 Return a monadic value that encapsulates @var{val}.
6775 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
6776 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
6777 procedures @var{mproc}@dots{}@footnote{This operation is commonly
6778 referred to as ``bind'', but that name denotes an unrelated procedure in
6779 Guile. Thus we use this somewhat cryptic symbol inherited from the
6780 Haskell language.}. There can be one @var{mproc} or several of them, as
6785 (with-monad %state-monad
6787 (lambda (x) (return (+ 1 x)))
6788 (lambda (x) (return (* 2 x)))))
6792 @result{} some-state
6796 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
6798 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
6800 Bind the variables @var{var} to the monadic values @var{mval} in
6801 @var{body}, which is a sequence of expressions. As with the bind
6802 operator, this can be thought of as ``unpacking'' the raw, non-monadic
6803 value ``contained'' in @var{mval} and making @var{var} refer to that
6804 raw, non-monadic value within the scope of the @var{body}. The form
6805 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
6806 @var{val}, as per @code{let}. The binding operations occur in sequence
6807 from left to right. The last expression of @var{body} must be a monadic
6808 expression, and its result will become the result of the @code{mlet} or
6809 @code{mlet*} when run in the @var{monad}.
6811 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
6812 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
6815 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
6816 Bind @var{mexp} and the following monadic expressions in sequence,
6817 returning the result of the last expression. Every expression in the
6818 sequence must be a monadic expression.
6820 This is akin to @code{mlet}, except that the return values of the
6821 monadic expressions are ignored. In that sense, it is analogous to
6822 @code{begin}, but applied to monadic expressions.
6825 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
6826 When @var{condition} is true, evaluate the sequence of monadic
6827 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6828 @var{condition} is false, return @code{*unspecified*} in the current
6829 monad. Every expression in the sequence must be a monadic expression.
6832 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
6833 When @var{condition} is false, evaluate the sequence of monadic
6834 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6835 @var{condition} is true, return @code{*unspecified*} in the current
6836 monad. Every expression in the sequence must be a monadic expression.
6840 The @code{(guix monads)} module provides the @dfn{state monad}, which
6841 allows an additional value---the state---to be @emph{threaded} through
6842 monadic procedure calls.
6844 @defvr {Scheme Variable} %state-monad
6845 The state monad. Procedures in the state monad can access and change
6846 the state that is threaded.
6848 Consider the example below. The @code{square} procedure returns a value
6849 in the state monad. It returns the square of its argument, but also
6850 increments the current state value:
6854 (mlet %state-monad ((count (current-state)))
6855 (mbegin %state-monad
6856 (set-current-state (+ 1 count))
6859 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
6864 When ``run'' through @var{%state-monad}, we obtain that additional state
6865 value, which is the number of @code{square} calls.
6868 @deffn {Monadic Procedure} current-state
6869 Return the current state as a monadic value.
6872 @deffn {Monadic Procedure} set-current-state @var{value}
6873 Set the current state to @var{value} and return the previous state as a
6877 @deffn {Monadic Procedure} state-push @var{value}
6878 Push @var{value} to the current state, which is assumed to be a list,
6879 and return the previous state as a monadic value.
6882 @deffn {Monadic Procedure} state-pop
6883 Pop a value from the current state and return it as a monadic value.
6884 The state is assumed to be a list.
6887 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
6888 Run monadic value @var{mval} starting with @var{state} as the initial
6889 state. Return two values: the resulting value, and the resulting state.
6892 The main interface to the store monad, provided by the @code{(guix
6893 store)} module, is as follows.
6895 @defvr {Scheme Variable} %store-monad
6896 The store monad---an alias for @var{%state-monad}.
6898 Values in the store monad encapsulate accesses to the store. When its
6899 effect is needed, a value of the store monad must be ``evaluated'' by
6900 passing it to the @code{run-with-store} procedure (see below.)
6903 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
6904 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
6905 open store connection.
6908 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
6909 Return as a monadic value the absolute file name in the store of the file
6910 containing @var{text}, a string. @var{references} is a list of store items that the
6911 resulting text file refers to; it defaults to the empty list.
6914 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
6915 Return as a monadic value the absolute file name in the store of the file
6916 containing @var{data}, a bytevector. @var{references} is a list of store
6917 items that the resulting binary file refers to; it defaults to the empty list.
6920 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
6921 [#:recursive? #t] [#:select? (const #t)]
6922 Return the name of @var{file} once interned in the store. Use
6923 @var{name} as its store name, or the basename of @var{file} if
6924 @var{name} is omitted.
6926 When @var{recursive?} is true, the contents of @var{file} are added
6927 recursively; if @var{file} designates a flat file and @var{recursive?}
6928 is true, its contents are added, and its permission bits are kept.
6930 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
6931 @var{stat})} for each directory entry, where @var{file} is the entry's
6932 absolute file name and @var{stat} is the result of @code{lstat}; exclude
6933 entries for which @var{select?} does not return true.
6935 The example below adds a file to the store, under two different names:
6938 (run-with-store (open-connection)
6939 (mlet %store-monad ((a (interned-file "README"))
6940 (b (interned-file "README" "LEGU-MIN")))
6941 (return (list a b))))
6943 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
6948 The @code{(guix packages)} module exports the following package-related
6951 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
6952 [#:system (%current-system)] [#:target #f] @
6955 value in the absolute file name of @var{file} within the @var{output}
6956 directory of @var{package}. When @var{file} is omitted, return the name
6957 of the @var{output} directory of @var{package}. When @var{target} is
6958 true, use it as a cross-compilation target triplet.
6961 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
6962 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
6963 @var{target} [@var{system}]
6964 Monadic version of @code{package-derivation} and
6965 @code{package-cross-derivation} (@pxref{Defining Packages}).
6970 @section G-Expressions
6972 @cindex G-expression
6973 @cindex build code quoting
6974 So we have ``derivations'', which represent a sequence of build actions
6975 to be performed to produce an item in the store (@pxref{Derivations}).
6976 These build actions are performed when asking the daemon to actually
6977 build the derivations; they are run by the daemon in a container
6978 (@pxref{Invoking guix-daemon}).
6980 @cindex strata of code
6981 It should come as no surprise that we like to write these build actions
6982 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
6983 code@footnote{The term @dfn{stratum} in this context was coined by
6984 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
6985 Kiselyov, who has written insightful
6986 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
6987 on this topic}, refers to this kind of code generation as
6988 @dfn{staging}.}: the ``host code''---code that defines packages, talks
6989 to the daemon, etc.---and the ``build code''---code that actually
6990 performs build actions, such as making directories, invoking
6991 @command{make}, etc.
6993 To describe a derivation and its build actions, one typically needs to
6994 embed build code inside host code. It boils down to manipulating build
6995 code as data, and the homoiconicity of Scheme---code has a direct
6996 representation as data---comes in handy for that. But we need more than
6997 the normal @code{quasiquote} mechanism in Scheme to construct build
7000 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7001 S-expressions adapted to build expressions. G-expressions, or
7002 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7003 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7004 @code{#$}, and @code{#$@@}), which are comparable to
7005 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7006 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7007 GNU Guile Reference Manual}). However, there are major differences:
7011 Gexps are meant to be written to a file and run or manipulated by other
7015 When a high-level object such as a package or derivation is unquoted
7016 inside a gexp, the result is as if its output file name had been
7020 Gexps carry information about the packages or derivations they refer to,
7021 and these dependencies are automatically added as inputs to the build
7022 processes that use them.
7025 @cindex lowering, of high-level objects in gexps
7026 This mechanism is not limited to package and derivation
7027 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7028 derivations or files in the store can be defined,
7029 such that these objects can also be inserted
7030 into gexps. For example, a useful type of high-level objects that can be
7031 inserted in a gexp is ``file-like objects'', which make it easy to
7032 add files to the store and to refer to them in
7033 derivations and such (see @code{local-file} and @code{plain-file}
7036 To illustrate the idea, here is an example of a gexp:
7043 (symlink (string-append #$coreutils "/bin/ls")
7047 This gexp can be passed to @code{gexp->derivation}; we obtain a
7048 derivation that builds a directory containing exactly one symlink to
7049 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7052 (gexp->derivation "the-thing" build-exp)
7055 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7056 substituted to the reference to the @var{coreutils} package in the
7057 actual build code, and @var{coreutils} is automatically made an input to
7058 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7059 output)}) is replaced by a string containing the directory name of the
7060 output of the derivation.
7062 @cindex cross compilation
7063 In a cross-compilation context, it is useful to distinguish between
7064 references to the @emph{native} build of a package---that can run on the
7065 host---versus references to cross builds of a package. To that end, the
7066 @code{#+} plays the same role as @code{#$}, but is a reference to a
7067 native package build:
7070 (gexp->derivation "vi"
7073 (system* (string-append #+coreutils "/bin/ln")
7075 (string-append #$emacs "/bin/emacs")
7076 (string-append #$output "/bin/vi")))
7077 #:target "mips64el-linux-gnu")
7081 In the example above, the native build of @var{coreutils} is used, so
7082 that @command{ln} can actually run on the host; but then the
7083 cross-compiled build of @var{emacs} is referenced.
7085 @cindex imported modules, for gexps
7086 @findex with-imported-modules
7087 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7088 able to use certain Guile modules from the ``host environment'' in the
7089 gexp, so those modules should be imported in the ``build environment''.
7090 The @code{with-imported-modules} form allows you to express that:
7093 (let ((build (with-imported-modules '((guix build utils))
7095 (use-modules (guix build utils))
7096 (mkdir-p (string-append #$output "/bin"))))))
7097 (gexp->derivation "empty-dir"
7100 (display "success!\n")
7105 In this example, the @code{(guix build utils)} module is automatically
7106 pulled into the isolated build environment of our gexp, such that
7107 @code{(use-modules (guix build utils))} works as expected.
7109 @cindex module closure
7110 @findex source-module-closure
7111 Usually you want the @emph{closure} of the module to be imported---i.e.,
7112 the module itself and all the modules it depends on---rather than just
7113 the module; failing to do that, attempts to use the module will fail
7114 because of missing dependent modules. The @code{source-module-closure}
7115 procedure computes the closure of a module by looking at its source file
7116 headers, which comes in handy in this case:
7119 (use-modules (guix modules)) ;for 'source-module-closure'
7121 (with-imported-modules (source-module-closure
7122 '((guix build utils)
7124 (gexp->derivation "something-with-vms"
7126 (use-modules (guix build utils)
7131 @cindex extensions, for gexps
7132 @findex with-extensions
7133 In the same vein, sometimes you want to import not just pure-Scheme
7134 modules, but also ``extensions'' such as Guile bindings to C libraries
7135 or other ``full-blown'' packages. Say you need the @code{guile-json}
7136 package available on the build side, here's how you would do it:
7139 (use-modules (gnu packages guile)) ;for 'guile-json'
7141 (with-extensions (list guile-json)
7142 (gexp->derivation "something-with-json"
7144 (use-modules (json))
7148 The syntactic form to construct gexps is summarized below.
7150 @deffn {Scheme Syntax} #~@var{exp}
7151 @deffnx {Scheme Syntax} (gexp @var{exp})
7152 Return a G-expression containing @var{exp}. @var{exp} may contain one
7153 or more of the following forms:
7157 @itemx (ungexp @var{obj})
7158 Introduce a reference to @var{obj}. @var{obj} may have one of the
7159 supported types, for example a package or a
7160 derivation, in which case the @code{ungexp} form is replaced by its
7161 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7163 If @var{obj} is a list, it is traversed and references to supported
7164 objects are substituted similarly.
7166 If @var{obj} is another gexp, its contents are inserted and its
7167 dependencies are added to those of the containing gexp.
7169 If @var{obj} is another kind of object, it is inserted as is.
7171 @item #$@var{obj}:@var{output}
7172 @itemx (ungexp @var{obj} @var{output})
7173 This is like the form above, but referring explicitly to the
7174 @var{output} of @var{obj}---this is useful when @var{obj} produces
7175 multiple outputs (@pxref{Packages with Multiple Outputs}).
7178 @itemx #+@var{obj}:output
7179 @itemx (ungexp-native @var{obj})
7180 @itemx (ungexp-native @var{obj} @var{output})
7181 Same as @code{ungexp}, but produces a reference to the @emph{native}
7182 build of @var{obj} when used in a cross compilation context.
7184 @item #$output[:@var{output}]
7185 @itemx (ungexp output [@var{output}])
7186 Insert a reference to derivation output @var{output}, or to the main
7187 output when @var{output} is omitted.
7189 This only makes sense for gexps passed to @code{gexp->derivation}.
7192 @itemx (ungexp-splicing @var{lst})
7193 Like the above, but splices the contents of @var{lst} inside the
7197 @itemx (ungexp-native-splicing @var{lst})
7198 Like the above, but refers to native builds of the objects listed in
7203 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7204 of the @code{gexp?} type (see below.)
7207 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7208 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7209 in their execution environment.
7211 Each item in @var{modules} can be the name of a module, such as
7212 @code{(guix build utils)}, or it can be a module name, followed by an
7213 arrow, followed by a file-like object:
7216 `((guix build utils)
7218 ((guix config) => ,(scheme-file "config.scm"
7219 #~(define-module @dots{}))))
7223 In the example above, the first two modules are taken from the search
7224 path, and the last one is created from the given file-like object.
7226 This form has @emph{lexical} scope: it has an effect on the gexps
7227 directly defined in @var{body}@dots{}, but not on those defined, say, in
7228 procedures called from @var{body}@dots{}.
7231 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7232 Mark the gexps defined in @var{body}@dots{} as requiring
7233 @var{extensions} in their build and execution environment.
7234 @var{extensions} is typically a list of package objects such as those
7235 defined in the @code{(gnu packages guile)} module.
7237 Concretely, the packages listed in @var{extensions} are added to the
7238 load path while compiling imported modules in @var{body}@dots{}; they
7239 are also added to the load path of the gexp returned by
7243 @deffn {Scheme Procedure} gexp? @var{obj}
7244 Return @code{#t} if @var{obj} is a G-expression.
7247 G-expressions are meant to be written to disk, either as code building
7248 some derivation, or as plain files in the store. The monadic procedures
7249 below allow you to do that (@pxref{The Store Monad}, for more
7250 information about monads.)
7252 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7253 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7254 [#:hash #f] [#:hash-algo #f] @
7255 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7256 [#:module-path @var{%load-path}] @
7257 [#:effective-version "2.2"] @
7258 [#:references-graphs #f] [#:allowed-references #f] @
7259 [#:disallowed-references #f] @
7260 [#:leaked-env-vars #f] @
7261 [#:script-name (string-append @var{name} "-builder")] @
7262 [#:deprecation-warnings #f] @
7263 [#:local-build? #f] [#:substitutable? #t] @
7264 [#:properties '()] [#:guile-for-build #f]
7265 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7266 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7267 stored in a file called @var{script-name}. When @var{target} is true,
7268 it is used as the cross-compilation target triplet for packages referred
7271 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7273 make @var{modules} available in the evaluation context of @var{exp};
7274 @var{modules} is a list of names of Guile modules searched in
7275 @var{module-path} to be copied in the store, compiled, and made available in
7276 the load path during the execution of @var{exp}---e.g., @code{((guix
7277 build utils) (guix build gnu-build-system))}.
7279 @var{effective-version} determines the string to use when adding extensions of
7280 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7282 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7285 When @var{references-graphs} is true, it must be a list of tuples of one of the
7289 (@var{file-name} @var{package})
7290 (@var{file-name} @var{package} @var{output})
7291 (@var{file-name} @var{derivation})
7292 (@var{file-name} @var{derivation} @var{output})
7293 (@var{file-name} @var{store-item})
7296 The right-hand-side of each element of @var{references-graphs} is automatically made
7297 an input of the build process of @var{exp}. In the build environment, each
7298 @var{file-name} contains the reference graph of the corresponding item, in a simple
7301 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7302 In the latter case, the list denotes store items that the result is allowed to
7303 refer to. Any reference to another store item will lead to a build error.
7304 Similarly for @var{disallowed-references}, which can list items that must not be
7305 referenced by the outputs.
7307 @var{deprecation-warnings} determines whether to show deprecation warnings while
7308 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7310 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7313 @cindex file-like objects
7314 The @code{local-file}, @code{plain-file}, @code{computed-file},
7315 @code{program-file}, and @code{scheme-file} procedures below return
7316 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7317 these objects lead to a file in the store. Consider this G-expression:
7320 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7321 #$(local-file "/tmp/my-nscd.conf"))
7324 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7325 to the store. Once expanded, for instance @i{via}
7326 @code{gexp->derivation}, the G-expression refers to that copy under
7327 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7328 does not have any effect on what the G-expression does.
7329 @code{plain-file} can be used similarly; it differs in that the file
7330 content is directly passed as a string.
7332 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7333 [#:recursive? #f] [#:select? (const #t)]
7334 Return an object representing local file @var{file} to add to the store; this
7335 object can be used in a gexp. If @var{file} is a relative file name, it is looked
7336 up relative to the source file where this form appears. @var{file} will be added to
7337 the store under @var{name}--by default the base name of @var{file}.
7339 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7340 designates a flat file and @var{recursive?} is true, its contents are added, and its
7341 permission bits are kept.
7343 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7344 @var{stat})} for each directory entry, where @var{file} is the entry's
7345 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7346 entries for which @var{select?} does not return true.
7348 This is the declarative counterpart of the @code{interned-file} monadic
7349 procedure (@pxref{The Store Monad, @code{interned-file}}).
7352 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7353 Return an object representing a text file called @var{name} with the given
7354 @var{content} (a string or a bytevector) to be added to the store.
7356 This is the declarative counterpart of @code{text-file}.
7359 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7360 [#:options '(#:local-build? #t)]
7361 Return an object representing the store item @var{name}, a file or
7362 directory computed by @var{gexp}. @var{options}
7363 is a list of additional arguments to pass to @code{gexp->derivation}.
7365 This is the declarative counterpart of @code{gexp->derivation}.
7368 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7369 [#:guile (default-guile)] [#:module-path %load-path]
7370 Return an executable script @var{name} that runs @var{exp} using
7371 @var{guile}, with @var{exp}'s imported modules in its search path.
7372 Look up @var{exp}'s modules in @var{module-path}.
7374 The example below builds a script that simply invokes the @command{ls}
7378 (use-modules (guix gexp) (gnu packages base))
7380 (gexp->script "list-files"
7381 #~(execl #$(file-append coreutils "/bin/ls")
7385 When ``running'' it through the store (@pxref{The Store Monad,
7386 @code{run-with-store}}), we obtain a derivation that produces an
7387 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7390 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7392 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7396 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7397 [#:guile #f] [#:module-path %load-path]
7398 Return an object representing the executable store item @var{name} that
7399 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7400 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7402 This is the declarative counterpart of @code{gexp->script}.
7405 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7406 [#:set-load-path? #t] [#:module-path %load-path] @
7408 [#:guile (default-guile)]
7409 Return a derivation that builds a file @var{name} containing @var{exp}.
7410 When @var{splice?} is true, @var{exp} is considered to be a list of
7411 expressions that will be spliced in the resulting file.
7413 When @var{set-load-path?} is true, emit code in the resulting file to
7414 set @code{%load-path} and @code{%load-compiled-path} to honor
7415 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7418 The resulting file holds references to all the dependencies of @var{exp}
7419 or a subset thereof.
7422 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7423 Return an object representing the Scheme file @var{name} that contains
7426 This is the declarative counterpart of @code{gexp->file}.
7429 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7430 Return as a monadic value a derivation that builds a text file
7431 containing all of @var{text}. @var{text} may list, in addition to
7432 strings, objects of any type that can be used in a gexp: packages,
7433 derivations, local file objects, etc. The resulting store file holds
7434 references to all these.
7436 This variant should be preferred over @code{text-file} anytime the file
7437 to create will reference items from the store. This is typically the
7438 case when building a configuration file that embeds store file names,
7442 (define (profile.sh)
7443 ;; Return the name of a shell script in the store that
7444 ;; initializes the 'PATH' environment variable.
7445 (text-file* "profile.sh"
7446 "export PATH=" coreutils "/bin:"
7447 grep "/bin:" sed "/bin\n"))
7450 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7451 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7452 preventing them from being garbage-collected during its lifetime.
7455 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7456 Return an object representing store file @var{name} containing
7457 @var{text}. @var{text} is a sequence of strings and file-like objects,
7461 (mixed-text-file "profile"
7462 "export PATH=" coreutils "/bin:" grep "/bin")
7465 This is the declarative counterpart of @code{text-file*}.
7468 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7469 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7470 Each item in @var{files} must be a two-element list where the first element is the
7471 file name to use in the new directory, and the second element is a gexp
7472 denoting the target file. Here's an example:
7476 `(("hosts" ,(plain-file "hosts"
7477 "127.0.0.1 localhost"))
7478 ("bashrc" ,(plain-file "bashrc"
7479 "alias ls='ls --color=auto'"))))
7482 This yields an @code{etc} directory containing these two files.
7485 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
7486 Return a directory that is the union of @var{things}, where @var{things} is a list of
7487 file-like objects denoting directories. For example:
7490 (directory-union "guile+emacs" (list guile emacs))
7493 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
7496 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
7497 Return a file-like object that expands to the concatenation of @var{obj}
7498 and @var{suffix}, where @var{obj} is a lowerable object and each
7499 @var{suffix} is a string.
7501 As an example, consider this gexp:
7504 (gexp->script "run-uname"
7505 #~(system* #$(file-append coreutils
7509 The same effect could be achieved with:
7512 (gexp->script "run-uname"
7513 #~(system* (string-append #$coreutils
7517 There is one difference though: in the @code{file-append} case, the
7518 resulting script contains the absolute file name as a string, whereas in
7519 the second case, the resulting script contains a @code{(string-append
7520 @dots{})} expression to construct the file name @emph{at run time}.
7524 Of course, in addition to gexps embedded in ``host'' code, there are
7525 also modules containing build tools. To make it clear that they are
7526 meant to be used in the build stratum, these modules are kept in the
7527 @code{(guix build @dots{})} name space.
7529 @cindex lowering, of high-level objects in gexps
7530 Internally, high-level objects are @dfn{lowered}, using their compiler,
7531 to either derivations or store items. For instance, lowering a package
7532 yields a derivation, and lowering a @code{plain-file} yields a store
7533 item. This is achieved using the @code{lower-object} monadic procedure.
7535 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
7537 Return as a value in @var{%store-monad} the derivation or store item
7538 corresponding to @var{obj} for @var{system}, cross-compiling for
7539 @var{target} if @var{target} is true. @var{obj} must be an object that
7540 has an associated gexp compiler, such as a @code{<package>}.
7543 @node Invoking guix repl
7544 @section Invoking @command{guix repl}
7546 @cindex REPL, read-eval-print loop
7547 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
7548 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
7549 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
7550 command, @command{guix repl} guarantees that all the Guix modules and all its
7551 dependencies are available in the search path. You can use it this way:
7555 scheme@@(guile-user)> ,use (gnu packages base)
7556 scheme@@(guile-user)> coreutils
7557 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
7561 In addition, @command{guix repl} implements a simple machine-readable REPL
7562 protocol for use by @code{(guix inferior)}, a facility to interact with
7563 @dfn{inferiors}, separate processes running a potentially different revision
7566 The available options are as follows:
7569 @item --type=@var{type}
7570 @itemx -t @var{type}
7571 Start a REPL of the given @var{TYPE}, which can be one of the following:
7575 This is default, and it spawns a standard full-featured Guile REPL.
7577 Spawn a REPL that uses the machine-readable protocol. This is the protocol
7578 that the @code{(guix inferior)} module speaks.
7581 @item --listen=@var{endpoint}
7582 By default, @command{guix repl} reads from standard input and writes to
7583 standard output. When this option is passed, it will instead listen for
7584 connections on @var{endpoint}. Here are examples of valid options:
7587 @item --listen=tcp:37146
7588 Accept connections on localhost on port 37146.
7590 @item --listen=unix:/tmp/socket
7591 Accept connections on the Unix-domain socket @file{/tmp/socket}.
7595 @c *********************************************************************
7599 This section describes Guix command-line utilities. Some of them are
7600 primarily targeted at developers and users who write new package
7601 definitions, while others are more generally useful. They complement
7602 the Scheme programming interface of Guix in a convenient way.
7605 * Invoking guix build:: Building packages from the command line.
7606 * Invoking guix edit:: Editing package definitions.
7607 * Invoking guix download:: Downloading a file and printing its hash.
7608 * Invoking guix hash:: Computing the cryptographic hash of a file.
7609 * Invoking guix import:: Importing package definitions.
7610 * Invoking guix refresh:: Updating package definitions.
7611 * Invoking guix lint:: Finding errors in package definitions.
7612 * Invoking guix size:: Profiling disk usage.
7613 * Invoking guix graph:: Visualizing the graph of packages.
7614 * Invoking guix publish:: Sharing substitutes.
7615 * Invoking guix challenge:: Challenging substitute servers.
7616 * Invoking guix copy:: Copying to and from a remote store.
7617 * Invoking guix container:: Process isolation.
7618 * Invoking guix weather:: Assessing substitute availability.
7619 * Invoking guix processes:: Listing client processes.
7622 @node Invoking guix build
7623 @section Invoking @command{guix build}
7625 @cindex package building
7626 @cindex @command{guix build}
7627 The @command{guix build} command builds packages or derivations and
7628 their dependencies, and prints the resulting store paths. Note that it
7629 does not modify the user's profile---this is the job of the
7630 @command{guix package} command (@pxref{Invoking guix package}). Thus,
7631 it is mainly useful for distribution developers.
7633 The general syntax is:
7636 guix build @var{options} @var{package-or-derivation}@dots{}
7639 As an example, the following command builds the latest versions of Emacs
7640 and of Guile, displays their build logs, and finally displays the
7641 resulting directories:
7644 guix build emacs guile
7647 Similarly, the following command builds all the available packages:
7650 guix build --quiet --keep-going \
7651 `guix package -A | cut -f1,2 --output-delimiter=@@`
7654 @var{package-or-derivation} may be either the name of a package found in
7655 the software distribution such as @code{coreutils} or
7656 @code{coreutils@@8.20}, or a derivation such as
7657 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
7658 package with the corresponding name (and optionally version) is searched
7659 for among the GNU distribution modules (@pxref{Package Modules}).
7661 Alternatively, the @code{--expression} option may be used to specify a
7662 Scheme expression that evaluates to a package; this is useful when
7663 disambiguating among several same-named packages or package variants is
7666 There may be zero or more @var{options}. The available options are
7667 described in the subsections below.
7670 * Common Build Options:: Build options for most commands.
7671 * Package Transformation Options:: Creating variants of packages.
7672 * Additional Build Options:: Options specific to 'guix build'.
7673 * Debugging Build Failures:: Real life packaging experience.
7676 @node Common Build Options
7677 @subsection Common Build Options
7679 A number of options that control the build process are common to
7680 @command{guix build} and other commands that can spawn builds, such as
7681 @command{guix package} or @command{guix archive}. These are the
7686 @item --load-path=@var{directory}
7687 @itemx -L @var{directory}
7688 Add @var{directory} to the front of the package module search path
7689 (@pxref{Package Modules}).
7691 This allows users to define their own packages and make them visible to
7692 the command-line tools.
7696 Keep the build tree of failed builds. Thus, if a build fails, its build
7697 tree is kept under @file{/tmp}, in a directory whose name is shown at
7698 the end of the build log. This is useful when debugging build issues.
7699 @xref{Debugging Build Failures}, for tips and tricks on how to debug
7702 This option has no effect when connecting to a remote daemon with a
7703 @code{guix://} URI (@pxref{The Store, the @code{GUIX_DAEMON_SOCKET}
7708 Keep going when some of the derivations fail to build; return only once
7709 all the builds have either completed or failed.
7711 The default behavior is to stop as soon as one of the specified
7712 derivations has failed.
7716 Do not build the derivations.
7718 @anchor{fallback-option}
7720 When substituting a pre-built binary fails, fall back to building
7721 packages locally (@pxref{Substitution Failure}).
7723 @item --substitute-urls=@var{urls}
7724 @anchor{client-substitute-urls}
7725 Consider @var{urls} the whitespace-separated list of substitute source
7726 URLs, overriding the default list of URLs of @command{guix-daemon}
7727 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
7729 This means that substitutes may be downloaded from @var{urls}, provided
7730 they are signed by a key authorized by the system administrator
7731 (@pxref{Substitutes}).
7733 When @var{urls} is the empty string, substitutes are effectively
7736 @item --no-substitutes
7737 Do not use substitutes for build products. That is, always build things
7738 locally instead of allowing downloads of pre-built binaries
7739 (@pxref{Substitutes}).
7742 Do not ``graft'' packages. In practice, this means that package updates
7743 available as grafts are not applied. @xref{Security Updates}, for more
7744 information on grafts.
7746 @item --rounds=@var{n}
7747 Build each derivation @var{n} times in a row, and raise an error if
7748 consecutive build results are not bit-for-bit identical.
7750 This is a useful way to detect non-deterministic builds processes.
7751 Non-deterministic build processes are a problem because they make it
7752 practically impossible for users to @emph{verify} whether third-party
7753 binaries are genuine. @xref{Invoking guix challenge}, for more.
7755 Note that, currently, the differing build results are not kept around,
7756 so you will have to manually investigate in case of an error---e.g., by
7757 stashing one of the build results with @code{guix archive --export}
7758 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
7761 @item --no-build-hook
7762 Do not attempt to offload builds @i{via} the ``build hook'' of the daemon
7763 (@pxref{Daemon Offload Setup}). That is, always build things locally
7764 instead of offloading builds to remote machines.
7766 @item --max-silent-time=@var{seconds}
7767 When the build or substitution process remains silent for more than
7768 @var{seconds}, terminate it and report a build failure.
7770 By default, the daemon's setting is honored (@pxref{Invoking
7771 guix-daemon, @code{--max-silent-time}}).
7773 @item --timeout=@var{seconds}
7774 Likewise, when the build or substitution process lasts for more than
7775 @var{seconds}, terminate it and report a build failure.
7777 By default, the daemon's setting is honored (@pxref{Invoking
7778 guix-daemon, @code{--timeout}}).
7780 @c Note: This option is actually not part of %standard-build-options but
7781 @c most programs honor it.
7782 @cindex verbosity, of the command-line tools
7783 @cindex build logs, verbosity
7784 @item -v @var{level}
7785 @itemx --verbosity=@var{level}
7786 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
7787 output is produced, 1 is for quiet output, and 2 shows all the build log
7788 output on standard error.
7790 @item --cores=@var{n}
7792 Allow the use of up to @var{n} CPU cores for the build. The special
7793 value @code{0} means to use as many CPU cores as available.
7795 @item --max-jobs=@var{n}
7797 Allow at most @var{n} build jobs in parallel. @xref{Invoking
7798 guix-daemon, @code{--max-jobs}}, for details about this option and the
7799 equivalent @command{guix-daemon} option.
7801 @item --debug=@var{level}
7802 Produce debugging output coming from the build daemon. @var{level} must be an
7803 integer between 0 and 5; higher means more verbose output. Setting a level of
7804 4 or more may be helpful when debugging setup issues with the build daemon.
7808 Behind the scenes, @command{guix build} is essentially an interface to
7809 the @code{package-derivation} procedure of the @code{(guix packages)}
7810 module, and to the @code{build-derivations} procedure of the @code{(guix
7811 derivations)} module.
7813 In addition to options explicitly passed on the command line,
7814 @command{guix build} and other @command{guix} commands that support
7815 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
7817 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
7818 Users can define this variable to a list of command line options that
7819 will automatically be used by @command{guix build} and other
7820 @command{guix} commands that can perform builds, as in the example
7824 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
7827 These options are parsed independently, and the result is appended to
7828 the parsed command-line options.
7832 @node Package Transformation Options
7833 @subsection Package Transformation Options
7835 @cindex package variants
7836 Another set of command-line options supported by @command{guix build}
7837 and also @command{guix package} are @dfn{package transformation
7838 options}. These are options that make it possible to define @dfn{package
7839 variants}---for instance, packages built from different source code.
7840 This is a convenient way to create customized packages on the fly
7841 without having to type in the definitions of package variants
7842 (@pxref{Defining Packages}).
7846 @item --with-source=@var{source}
7847 @itemx --with-source=@var{package}=@var{source}
7848 @itemx --with-source=@var{package}@@@var{version}=@var{source}
7849 Use @var{source} as the source of @var{package}, and @var{version} as
7851 @var{source} must be a file name or a URL, as for @command{guix
7852 download} (@pxref{Invoking guix download}).
7854 When @var{package} is omitted,
7855 it is taken to be the package name specified on the
7856 command line that matches the base of @var{source}---e.g.,
7857 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
7858 package is @code{guile}.
7860 Likewise, when @var{version} is omitted, the version string is inferred from
7861 @var{source}; in the previous example, it is @code{2.0.10}.
7863 This option allows users to try out versions of packages other than the
7864 one provided by the distribution. The example below downloads
7865 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
7866 the @code{ed} package:
7869 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
7872 As a developer, @code{--with-source} makes it easy to test release
7876 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
7879 @dots{} or to build from a checkout in a pristine environment:
7882 $ git clone git://git.sv.gnu.org/guix.git
7883 $ guix build guix --with-source=guix@@1.0=./guix
7886 @item --with-input=@var{package}=@var{replacement}
7887 Replace dependency on @var{package} by a dependency on
7888 @var{replacement}. @var{package} must be a package name, and
7889 @var{replacement} must be a package specification such as @code{guile}
7890 or @code{guile@@1.8}.
7892 For instance, the following command builds Guix, but replaces its
7893 dependency on the current stable version of Guile with a dependency on
7894 the legacy version of Guile, @code{guile@@2.0}:
7897 guix build --with-input=guile=guile@@2.0 guix
7900 This is a recursive, deep replacement. So in this example, both
7901 @code{guix} and its dependency @code{guile-json} (which also depends on
7902 @code{guile}) get rebuilt against @code{guile@@2.0}.
7904 This is implemented using the @code{package-input-rewriting} Scheme
7905 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
7907 @item --with-graft=@var{package}=@var{replacement}
7908 This is similar to @code{--with-input} but with an important difference:
7909 instead of rebuilding the whole dependency chain, @var{replacement} is
7910 built and then @dfn{grafted} onto the binaries that were initially
7911 referring to @var{package}. @xref{Security Updates}, for more
7912 information on grafts.
7914 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
7915 and all its dependencies, replacing references to the version of GnuTLS
7916 they currently refer to:
7919 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
7922 This has the advantage of being much faster than rebuilding everything.
7923 But there is a caveat: it works if and only if @var{package} and
7924 @var{replacement} are strictly compatible---for example, if they provide
7925 a library, the application binary interface (ABI) of those libraries
7926 must be compatible. If @var{replacement} is somehow incompatible with
7927 @var{package}, then the resulting package may be unusable. Use with
7930 @item --with-git-url=@var{package}=@var{url}
7931 @cindex Git, using the latest commit
7932 @cindex latest commit, building
7933 Build @var{package} from the latest commit of the @code{master} branch of the
7934 Git repository at @var{url}. Git sub-modules of the repository are fetched,
7937 For example, the following command builds the NumPy Python library against the
7938 latest commit of the master branch of Python itself:
7941 guix build python-numpy \
7942 --with-git-url=python=https://github.com/python/cpython
7945 This option can also be combined with @code{--with-branch} or
7946 @code{--with-commit} (see below).
7948 @cindex continuous integration
7949 Obviously, since it uses the latest commit of the given branch, the result of
7950 such a command varies over time. Nevertheless it is a convenient way to
7951 rebuild entire software stacks against the latest commit of one or more
7952 packages. This is particularly useful in the context of continuous
7955 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
7956 consecutive accesses to the same repository. You may want to clean it up once
7957 in a while to save disk space.
7959 @item --with-branch=@var{package}=@var{branch}
7960 Build @var{package} from the latest commit of @var{branch}. If the
7961 @code{source} field of @var{package} is an origin with the @code{git-fetch}
7962 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
7963 repository URL is taken from that @code{source}. Otherwise you have to use
7964 @code{--with-git-url} to specify the URL of the Git repository.
7966 For instance, the following command builds @code{guile-sqlite3} from the
7967 latest commit of its @code{master} branch, and then builds @code{guix} (which
7968 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
7969 specific @code{guile-sqlite3} build:
7972 guix build --with-branch=guile-sqlite3=master cuirass
7975 @item --with-commit=@var{package}=@var{commit}
7976 This is similar to @code{--with-branch}, except that it builds from
7977 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
7978 Git commit SHA1 identifier.
7981 @node Additional Build Options
7982 @subsection Additional Build Options
7984 The command-line options presented below are specific to @command{guix
7991 Build quietly, without displaying the build log; this is equivalent to
7992 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
7993 (or similar) and can always be retrieved using the @option{--log-file} option.
7995 @item --file=@var{file}
7996 @itemx -f @var{file}
7997 Build the package, derivation, or other file-like object that the code within
7998 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8000 As an example, @var{file} might contain a package definition like this
8001 (@pxref{Defining Packages}):
8004 @verbatiminclude package-hello.scm
8007 @item --expression=@var{expr}
8008 @itemx -e @var{expr}
8009 Build the package or derivation @var{expr} evaluates to.
8011 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8012 guile-1.8)}, which unambiguously designates this specific variant of
8013 version 1.8 of Guile.
8015 Alternatively, @var{expr} may be a G-expression, in which case it is used
8016 as a build program passed to @code{gexp->derivation}
8017 (@pxref{G-Expressions}).
8019 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8020 (@pxref{The Store Monad}). The procedure must return a derivation as a
8021 monadic value, which is then passed through @code{run-with-store}.
8025 Build the source derivations of the packages, rather than the packages
8028 For instance, @code{guix build -S gcc} returns something like
8029 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8032 The returned source tarball is the result of applying any patches and
8033 code snippets specified in the package @code{origin} (@pxref{Defining
8037 Fetch and return the source of @var{package-or-derivation} and all their
8038 dependencies, recursively. This is a handy way to obtain a local copy
8039 of all the source code needed to build @var{packages}, allowing you to
8040 eventually build them even without network access. It is an extension
8041 of the @code{--source} option and can accept one of the following
8042 optional argument values:
8046 This value causes the @code{--sources} option to behave in the same way
8047 as the @code{--source} option.
8050 Build the source derivations of all packages, including any source that
8051 might be listed as @code{inputs}. This is the default value.
8054 $ guix build --sources tzdata
8055 The following derivations will be built:
8056 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8057 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8061 Build the source derivations of all packages, as well of all transitive
8062 inputs to the packages. This can be used e.g.@: to
8063 prefetch package source for later offline building.
8066 $ guix build --sources=transitive tzdata
8067 The following derivations will be built:
8068 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8069 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8070 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8071 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8072 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8073 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8079 @item --system=@var{system}
8080 @itemx -s @var{system}
8081 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8082 the system type of the build host. The @command{guix build} command allows
8083 you to repeat this option several times, in which case it builds for all the
8084 specified systems; other commands ignore extraneous @option{-s} options.
8087 The @code{--system} flag is for @emph{native} compilation and must not
8088 be confused with cross-compilation. See @code{--target} below for
8089 information on cross-compilation.
8092 An example use of this is on Linux-based systems, which can emulate
8093 different personalities. For instance, passing
8094 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8095 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8096 to build packages in a complete 32-bit environment.
8099 Building for an @code{armhf-linux} system is unconditionally enabled on
8100 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8101 allow for this functionality, notably the ThunderX.
8104 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8105 is enabled (@pxref{Virtualization Services,
8106 @code{qemu-binfmt-service-type}}), you can build for any system for
8107 which a QEMU @code{binfmt_misc} handler is installed.
8109 Builds for a system other than that of the machine you are using can
8110 also be offloaded to a remote machine of the right architecture.
8111 @xref{Daemon Offload Setup}, for more information on offloading.
8113 @item --target=@var{triplet}
8114 @cindex cross-compilation
8115 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8116 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8117 configuration triplets,, autoconf, Autoconf}).
8119 @anchor{build-check}
8121 @cindex determinism, checking
8122 @cindex reproducibility, checking
8123 Rebuild @var{package-or-derivation}, which are already available in the
8124 store, and raise an error if the build results are not bit-for-bit
8127 This mechanism allows you to check whether previously installed
8128 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8129 of a package is deterministic. @xref{Invoking guix challenge}, for more
8130 background information and tools.
8132 When used in conjunction with @option{--keep-failed}, the differing
8133 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8134 This makes it easy to look for differences between the two results.
8137 @cindex repairing store items
8138 @cindex corruption, recovering from
8139 Attempt to repair the specified store items, if they are corrupt, by
8140 re-downloading or rebuilding them.
8142 This operation is not atomic and thus restricted to @code{root}.
8146 Return the derivation paths, not the output paths, of the given
8149 @item --root=@var{file}
8150 @itemx -r @var{file}
8151 @cindex GC roots, adding
8152 @cindex garbage collector roots, adding
8153 Make @var{file} a symlink to the result, and register it as a garbage
8156 Consequently, the results of this @command{guix build} invocation are
8157 protected from garbage collection until @var{file} is removed. When
8158 that option is omitted, build results are eligible for garbage
8159 collection as soon as the build completes. @xref{Invoking guix gc}, for
8163 @cindex build logs, access
8164 Return the build log file names or URLs for the given
8165 @var{package-or-derivation}, or raise an error if build logs are
8168 This works regardless of how packages or derivations are specified. For
8169 instance, the following invocations are equivalent:
8172 guix build --log-file `guix build -d guile`
8173 guix build --log-file `guix build guile`
8174 guix build --log-file guile
8175 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8178 If a log is unavailable locally, and unless @code{--no-substitutes} is
8179 passed, the command looks for a corresponding log on one of the
8180 substitute servers (as specified with @code{--substitute-urls}.)
8182 So for instance, imagine you want to see the build log of GDB on MIPS,
8183 but you are actually on an @code{x86_64} machine:
8186 $ guix build --log-file gdb -s mips64el-linux
8187 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8190 You can freely access a huge library of build logs!
8193 @node Debugging Build Failures
8194 @subsection Debugging Build Failures
8196 @cindex build failures, debugging
8197 When defining a new package (@pxref{Defining Packages}), you will
8198 probably find yourself spending some time debugging and tweaking the
8199 build until it succeeds. To do that, you need to operate the build
8200 commands yourself in an environment as close as possible to the one the
8203 To that end, the first thing to do is to use the @option{--keep-failed}
8204 or @option{-K} option of @command{guix build}, which will keep the
8205 failed build tree in @file{/tmp} or whatever directory you specified as
8206 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8208 From there on, you can @command{cd} to the failed build tree and source
8209 the @file{environment-variables} file, which contains all the
8210 environment variable definitions that were in place when the build
8211 failed. So let's say you're debugging a build failure in package
8212 @code{foo}; a typical session would look like this:
8216 @dots{} @i{build fails}
8217 $ cd /tmp/guix-build-foo.drv-0
8218 $ source ./environment-variables
8222 Now, you can invoke commands as if you were the daemon (almost) and
8223 troubleshoot your build process.
8225 Sometimes it happens that, for example, a package's tests pass when you
8226 run them manually but they fail when the daemon runs them. This can
8227 happen because the daemon runs builds in containers where, unlike in our
8228 environment above, network access is missing, @file{/bin/sh} does not
8229 exist, etc. (@pxref{Build Environment Setup}).
8231 In such cases, you may need to run inspect the build process from within
8232 a container similar to the one the build daemon creates:
8237 $ cd /tmp/guix-build-foo.drv-0
8238 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8239 [env]# source ./environment-variables
8243 Here, @command{guix environment -C} creates a container and spawns a new
8244 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8245 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8246 the container, which would may find handy while debugging. The
8247 @option{--no-grafts} option makes sure we get the exact same
8248 environment, with ungrafted packages (@pxref{Security Updates}, for more
8251 To get closer to a container like that used by the build daemon, we can
8252 remove @file{/bin/sh}:
8258 (Don't worry, this is harmless: this is all happening in the throw-away
8259 container created by @command{guix environment}.)
8261 The @command{strace} command is probably not in the search path, but we
8265 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8268 In this way, not only you will have reproduced the environment variables
8269 the daemon uses, you will also be running the build process in a container
8270 similar to the one the daemon uses.
8273 @node Invoking guix edit
8274 @section Invoking @command{guix edit}
8276 @cindex @command{guix edit}
8277 @cindex package definition, editing
8278 So many packages, so many source files! The @command{guix edit} command
8279 facilitates the life of users and packagers by pointing their editor at
8280 the source file containing the definition of the specified packages.
8284 guix edit gcc@@4.9 vim
8288 launches the program specified in the @code{VISUAL} or in the
8289 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8292 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8293 have created your own packages on @code{GUIX_PACKAGE_PATH}
8294 (@pxref{Package Modules}), you will be able to edit the package
8295 recipes. In other cases, you will be able to examine the read-only recipes
8296 for packages currently in the store.
8299 @node Invoking guix download
8300 @section Invoking @command{guix download}
8302 @cindex @command{guix download}
8303 @cindex downloading package sources
8304 When writing a package definition, developers typically need to download
8305 a source tarball, compute its SHA256 hash, and write that
8306 hash in the package definition (@pxref{Defining Packages}). The
8307 @command{guix download} tool helps with this task: it downloads a file
8308 from the given URI, adds it to the store, and prints both its file name
8309 in the store and its SHA256 hash.
8311 The fact that the downloaded file is added to the store saves bandwidth:
8312 when the developer eventually tries to build the newly defined package
8313 with @command{guix build}, the source tarball will not have to be
8314 downloaded again because it is already in the store. It is also a
8315 convenient way to temporarily stash files, which may be deleted
8316 eventually (@pxref{Invoking guix gc}).
8318 The @command{guix download} command supports the same URIs as used in
8319 package definitions. In particular, it supports @code{mirror://} URIs.
8320 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8321 Guile bindings for GnuTLS are available in the user's environment; when
8322 they are not available, an error is raised. @xref{Guile Preparations,
8323 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8324 GnuTLS-Guile}, for more information.
8326 @command{guix download} verifies HTTPS server certificates by loading
8327 the certificates of X.509 authorities from the directory pointed to by
8328 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8329 Certificates}), unless @option{--no-check-certificate} is used.
8331 The following options are available:
8334 @item --format=@var{fmt}
8336 Write the hash in the format specified by @var{fmt}. For more
8337 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8339 @item --no-check-certificate
8340 Do not validate the X.509 certificates of HTTPS servers.
8342 When using this option, you have @emph{absolutely no guarantee} that you
8343 are communicating with the authentic server responsible for the given
8344 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8346 @item --output=@var{file}
8347 @itemx -o @var{file}
8348 Save the downloaded file to @var{file} instead of adding it to the
8352 @node Invoking guix hash
8353 @section Invoking @command{guix hash}
8355 @cindex @command{guix hash}
8356 The @command{guix hash} command computes the SHA256 hash of a file.
8357 It is primarily a convenience tool for anyone contributing to the
8358 distribution: it computes the cryptographic hash of a file, which can be
8359 used in the definition of a package (@pxref{Defining Packages}).
8361 The general syntax is:
8364 guix hash @var{option} @var{file}
8367 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8368 hash of data read from standard input. @command{guix hash} has the
8373 @item --format=@var{fmt}
8375 Write the hash in the format specified by @var{fmt}.
8377 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8378 (@code{hex} and @code{hexadecimal} can be used as well).
8380 If the @option{--format} option is not specified, @command{guix hash}
8381 will output the hash in @code{nix-base32}. This representation is used
8382 in the definitions of packages.
8386 Compute the hash on @var{file} recursively.
8388 In this case, the hash is computed on an archive containing @var{file},
8389 including its children if it is a directory. Some of the metadata of
8390 @var{file} is part of the archive; for instance, when @var{file} is a
8391 regular file, the hash is different depending on whether @var{file} is
8392 executable or not. Metadata such as time stamps has no impact on the
8393 hash (@pxref{Invoking guix archive}).
8394 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8399 When combined with @option{--recursive}, exclude version control system
8400 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8403 As an example, here is how you would compute the hash of a Git checkout,
8404 which is useful when using the @code{git-fetch} method (@pxref{origin
8408 $ git clone http://example.org/foo.git
8414 @node Invoking guix import
8415 @section Invoking @command{guix import}
8417 @cindex importing packages
8418 @cindex package import
8419 @cindex package conversion
8420 @cindex Invoking @command{guix import}
8421 The @command{guix import} command is useful for people who would like to
8422 add a package to the distribution with as little work as
8423 possible---a legitimate demand. The command knows of a few
8424 repositories from which it can ``import'' package metadata. The result
8425 is a package definition, or a template thereof, in the format we know
8426 (@pxref{Defining Packages}).
8428 The general syntax is:
8431 guix import @var{importer} @var{options}@dots{}
8434 @var{importer} specifies the source from which to import package
8435 metadata, and @var{options} specifies a package identifier and other
8436 options specific to @var{importer}. Currently, the available
8441 Import metadata for the given GNU package. This provides a template
8442 for the latest version of that GNU package, including the hash of its
8443 source tarball, and its canonical synopsis and description.
8445 Additional information such as the package dependencies and its
8446 license needs to be figured out manually.
8448 For example, the following command returns a package definition for
8452 guix import gnu hello
8455 Specific command-line options are:
8458 @item --key-download=@var{policy}
8459 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
8460 keys when verifying the package signature. @xref{Invoking guix
8461 refresh, @code{--key-download}}.
8466 Import metadata from the @uref{https://pypi.python.org/, Python Package
8467 Index}. Information is taken from the JSON-formatted description
8468 available at @code{pypi.python.org} and usually includes all the relevant
8469 information, including package dependencies. For maximum efficiency, it
8470 is recommended to install the @command{unzip} utility, so that the
8471 importer can unzip Python wheels and gather data from them.
8473 The command below imports metadata for the @code{itsdangerous} Python
8477 guix import pypi itsdangerous
8483 Traverse the dependency graph of the given upstream package recursively
8484 and generate package expressions for all those packages that are not yet
8490 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
8491 is taken from the JSON-formatted description available at
8492 @code{rubygems.org} and includes most relevant information, including
8493 runtime dependencies. There are some caveats, however. The metadata
8494 doesn't distinguish between synopses and descriptions, so the same string
8495 is used for both fields. Additionally, the details of non-Ruby
8496 dependencies required to build native extensions is unavailable and left
8497 as an exercise to the packager.
8499 The command below imports metadata for the @code{rails} Ruby package:
8502 guix import gem rails
8508 Traverse the dependency graph of the given upstream package recursively
8509 and generate package expressions for all those packages that are not yet
8515 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
8516 Information is taken from the JSON-formatted metadata provided through
8517 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
8518 relevant information, such as module dependencies. License information
8519 should be checked closely. If Perl is available in the store, then the
8520 @code{corelist} utility will be used to filter core modules out of the
8521 list of dependencies.
8523 The command command below imports metadata for the @code{Acme::Boolean}
8527 guix import cpan Acme::Boolean
8532 @cindex Bioconductor
8533 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
8534 central repository for the @uref{https://r-project.org, GNU@tie{}R
8535 statistical and graphical environment}.
8537 Information is extracted from the @code{DESCRIPTION} file of the package.
8539 The command command below imports metadata for the @code{Cairo}
8543 guix import cran Cairo
8546 When @code{--recursive} is added, the importer will traverse the
8547 dependency graph of the given upstream package recursively and generate
8548 package expressions for all those packages that are not yet in Guix.
8550 When @code{--archive=bioconductor} is added, metadata is imported from
8551 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
8552 packages for for the analysis and comprehension of high-throughput
8553 genomic data in bioinformatics.
8555 Information is extracted from the @code{DESCRIPTION} file of a package
8556 published on the web interface of the Bioconductor SVN repository.
8558 The command below imports metadata for the @code{GenomicRanges}
8562 guix import cran --archive=bioconductor GenomicRanges
8568 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
8569 comprehensive TeX archive network for TeX packages that are part of the
8570 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
8572 Information about the package is obtained through the XML API provided
8573 by CTAN, while the source code is downloaded from the SVN repository of
8574 the Tex Live project. This is done because the CTAN does not keep
8577 The command command below imports metadata for the @code{fontspec}
8581 guix import texlive fontspec
8584 When @code{--archive=DIRECTORY} is added, the source code is downloaded
8585 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
8586 tree in the TeX Live SVN repository, but from the specified sibling
8587 directory under the same root.
8589 The command below imports metadata for the @code{ifxetex} package from
8590 CTAN while fetching the sources from the directory
8591 @file{texmf/source/generic}:
8594 guix import texlive --archive=generic ifxetex
8598 @cindex JSON, import
8599 Import package metadata from a local JSON file. Consider the following
8600 example package definition in JSON format:
8606 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
8607 "build-system": "gnu",
8608 "home-page": "https://www.gnu.org/software/hello/",
8609 "synopsis": "Hello, GNU world: An example GNU package",
8610 "description": "GNU Hello prints a greeting.",
8611 "license": "GPL-3.0+",
8612 "native-inputs": ["gcc@@6"]
8616 The field names are the same as for the @code{<package>} record
8617 (@xref{Defining Packages}). References to other packages are provided
8618 as JSON lists of quoted package specification strings such as
8619 @code{guile} or @code{guile@@2.0}.
8621 The importer also supports a more explicit source definition using the
8622 common fields for @code{<origin>} records:
8628 "method": "url-fetch",
8629 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
8631 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
8638 The command below reads metadata from the JSON file @code{hello.json}
8639 and outputs a package expression:
8642 guix import json hello.json
8646 Import metadata from a local copy of the source of the
8647 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
8648 relies on the @command{nix-instantiate} command of
8649 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
8650 typically written in a mixture of Nix-language and Bash code. This
8651 command only imports the high-level package structure that is written in
8652 the Nix language. It normally includes all the basic fields of a
8655 When importing a GNU package, the synopsis and descriptions are replaced
8656 by their canonical upstream variant.
8658 Usually, you will first need to do:
8661 export NIX_REMOTE=daemon
8665 so that @command{nix-instantiate} does not try to open the Nix database.
8667 As an example, the command below imports the package definition of
8668 LibreOffice (more precisely, it imports the definition of the package
8669 bound to the @code{libreoffice} top-level attribute):
8672 guix import nix ~/path/to/nixpkgs libreoffice
8677 Import metadata from the Haskell community's central package archive
8678 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
8679 Cabal files and includes all the relevant information, including package
8682 Specific command-line options are:
8687 Read a Cabal file from standard input.
8688 @item --no-test-dependencies
8690 Do not include dependencies required only by the test suites.
8691 @item --cabal-environment=@var{alist}
8692 @itemx -e @var{alist}
8693 @var{alist} is a Scheme alist defining the environment in which the
8694 Cabal conditionals are evaluated. The accepted keys are: @code{os},
8695 @code{arch}, @code{impl} and a string representing the name of a flag.
8696 The value associated with a flag has to be either the symbol
8697 @code{true} or @code{false}. The value associated with other keys
8698 has to conform to the Cabal file format definition. The default value
8699 associated with the keys @code{os}, @code{arch} and @code{impl} is
8700 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
8703 Traverse the dependency graph of the given upstream package recursively
8704 and generate package expressions for all those packages that are not yet
8708 The command below imports metadata for the latest version of the
8709 @code{HTTP} Haskell package without including test dependencies and
8710 specifying the value of the flag @samp{network-uri} as @code{false}:
8713 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
8716 A specific package version may optionally be specified by following the
8717 package name by an at-sign and a version number as in the following example:
8720 guix import hackage mtl@@2.1.3.1
8725 The @code{stackage} importer is a wrapper around the @code{hackage} one.
8726 It takes a package name, looks up the package version included in a
8727 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
8728 release and uses the @code{hackage} importer to retrieve its metadata.
8729 Note that it is up to you to select an LTS release compatible with the
8730 GHC compiler used by Guix.
8732 Specific command-line options are:
8735 @item --no-test-dependencies
8737 Do not include dependencies required only by the test suites.
8738 @item --lts-version=@var{version}
8739 @itemx -l @var{version}
8740 @var{version} is the desired LTS release version. If omitted the latest
8744 Traverse the dependency graph of the given upstream package recursively
8745 and generate package expressions for all those packages that are not yet
8749 The command below imports metadata for the @code{HTTP} Haskell package
8750 included in the LTS Stackage release version 7.18:
8753 guix import stackage --lts-version=7.18 HTTP
8758 Import metadata from an Emacs Lisp Package Archive (ELPA) package
8759 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
8761 Specific command-line options are:
8764 @item --archive=@var{repo}
8765 @itemx -a @var{repo}
8766 @var{repo} identifies the archive repository from which to retrieve the
8767 information. Currently the supported repositories and their identifiers
8771 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
8772 identifier. This is the default.
8774 Packages from @code{elpa.gnu.org} are signed with one of the keys
8775 contained in the GnuPG keyring at
8776 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
8777 @code{emacs} package (@pxref{Package Installation, ELPA package
8778 signatures,, emacs, The GNU Emacs Manual}).
8781 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
8782 @code{melpa-stable} identifier.
8785 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
8791 Traverse the dependency graph of the given upstream package recursively
8792 and generate package expressions for all those packages that are not yet
8798 Import metadata from the crates.io Rust package repository
8799 @uref{https://crates.io, crates.io}.
8804 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
8805 repository used by the OCaml community.
8808 The structure of the @command{guix import} code is modular. It would be
8809 useful to have more importers for other package formats, and your help
8810 is welcome here (@pxref{Contributing}).
8812 @node Invoking guix refresh
8813 @section Invoking @command{guix refresh}
8815 @cindex @command {guix refresh}
8816 The primary audience of the @command{guix refresh} command is developers
8817 of the GNU software distribution. By default, it reports any packages
8818 provided by the distribution that are outdated compared to the latest
8819 upstream version, like this:
8823 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
8824 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
8827 Alternately, one can specify packages to consider, in which case a
8828 warning is emitted for packages that lack an updater:
8831 $ guix refresh coreutils guile guile-ssh
8832 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
8833 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
8836 @command{guix refresh} browses the upstream repository of each package and determines
8837 the highest version number of the releases therein. The command
8838 knows how to update specific types of packages: GNU packages, ELPA
8839 packages, etc.---see the documentation for @option{--type} below. There
8840 are many packages, though, for which it lacks a method to determine
8841 whether a new upstream release is available. However, the mechanism is
8842 extensible, so feel free to get in touch with us to add a new method!
8847 Consider the packages specified, and all the packages upon which they depend.
8850 $ guix refresh --recursive coreutils
8851 gnu/packages/acl.scm:35:2: warning: no updater for acl
8852 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
8853 gnu/packages/xml.scm:68:2: warning: no updater for expat
8854 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
8860 Sometimes the upstream name differs from the package name used in Guix,
8861 and @command{guix refresh} needs a little help. Most updaters honor the
8862 @code{upstream-name} property in package definitions, which can be used
8866 (define-public network-manager
8868 (name "network-manager")
8870 (properties '((upstream-name . "NetworkManager")))))
8873 When passed @code{--update}, it modifies distribution source files to
8874 update the version numbers and source tarball hashes of those package
8875 recipes (@pxref{Defining Packages}). This is achieved by downloading
8876 each package's latest source tarball and its associated OpenPGP
8877 signature, authenticating the downloaded tarball against its signature
8878 using @command{gpg}, and finally computing its hash. When the public
8879 key used to sign the tarball is missing from the user's keyring, an
8880 attempt is made to automatically retrieve it from a public key server;
8881 when this is successful, the key is added to the user's keyring; otherwise,
8882 @command{guix refresh} reports an error.
8884 The following options are supported:
8888 @item --expression=@var{expr}
8889 @itemx -e @var{expr}
8890 Consider the package @var{expr} evaluates to.
8892 This is useful to precisely refer to a package, as in this example:
8895 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
8898 This command lists the dependents of the ``final'' libc (essentially all
8903 Update distribution source files (package recipes) in place. This is
8904 usually run from a checkout of the Guix source tree (@pxref{Running
8905 Guix Before It Is Installed}):
8908 $ ./pre-inst-env guix refresh -s non-core -u
8911 @xref{Defining Packages}, for more information on package definitions.
8913 @item --select=[@var{subset}]
8914 @itemx -s @var{subset}
8915 Select all the packages in @var{subset}, one of @code{core} or
8918 The @code{core} subset refers to all the packages at the core of the
8919 distribution---i.e., packages that are used to build ``everything
8920 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
8921 changing one of these packages in the distribution entails a rebuild of
8922 all the others. Thus, such updates are an inconvenience to users in
8923 terms of build time or bandwidth used to achieve the upgrade.
8925 The @code{non-core} subset refers to the remaining packages. It is
8926 typically useful in cases where an update of the core packages would be
8929 @item --manifest=@var{file}
8930 @itemx -m @var{file}
8931 Select all the packages from the manifest in @var{file}. This is useful to
8932 check if any packages of the user manifest can be updated.
8934 @item --type=@var{updater}
8935 @itemx -t @var{updater}
8936 Select only packages handled by @var{updater} (may be a comma-separated
8937 list of updaters). Currently, @var{updater} may be one of:
8941 the updater for GNU packages;
8943 the updater for GNOME packages;
8945 the updater for KDE packages;
8947 the updater for X.org packages;
8949 the updater for packages hosted on kernel.org;
8951 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
8953 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
8955 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
8957 the updater for @uref{https://www.cpan.org/, CPAN} packages;
8959 the updater for @uref{https://pypi.python.org, PyPI} packages.
8961 the updater for @uref{https://rubygems.org, RubyGems} packages.
8963 the updater for @uref{https://github.com, GitHub} packages.
8965 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
8967 the updater for @uref{https://www.stackage.org, Stackage} packages.
8969 the updater for @uref{https://crates.io, Crates} packages.
8971 the updater for @uref{https://launchpad.net, Launchpad} packages.
8974 For instance, the following command only checks for updates of Emacs
8975 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
8978 $ guix refresh --type=elpa,cran
8979 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
8980 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
8985 In addition, @command{guix refresh} can be passed one or more package
8986 names, as in this example:
8989 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
8993 The command above specifically updates the @code{emacs} and
8994 @code{idutils} packages. The @code{--select} option would have no
8995 effect in this case.
8997 When considering whether to upgrade a package, it is sometimes
8998 convenient to know which packages would be affected by the upgrade and
8999 should be checked for compatibility. For this the following option may
9000 be used when passing @command{guix refresh} one or more package names:
9004 @item --list-updaters
9006 List available updaters and exit (see @option{--type} above.)
9008 For each updater, display the fraction of packages it covers; at the
9009 end, display the fraction of packages covered by all these updaters.
9011 @item --list-dependent
9013 List top-level dependent packages that would need to be rebuilt as a
9014 result of upgrading one or more packages.
9016 @xref{Invoking guix graph, the @code{reverse-package} type of
9017 @command{guix graph}}, for information on how to visualize the list of
9018 dependents of a package.
9022 Be aware that the @code{--list-dependent} option only
9023 @emph{approximates} the rebuilds that would be required as a result of
9024 an upgrade. More rebuilds might be required under some circumstances.
9027 $ guix refresh --list-dependent flex
9028 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9029 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9032 The command above lists a set of packages that could be built to check
9033 for compatibility with an upgraded @code{flex} package.
9037 @item --list-transitive
9038 List all the packages which one or more packages depend upon.
9041 $ guix refresh --list-transitive flex
9042 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9043 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{}
9048 The command above lists a set of packages which, when changed, would cause
9049 @code{flex} to be rebuilt.
9051 The following options can be used to customize GnuPG operation:
9055 @item --gpg=@var{command}
9056 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9057 for in @code{$PATH}.
9059 @item --keyring=@var{file}
9060 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9061 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9062 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9063 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9064 information on a tool to manipulate keybox files).
9066 When this option is omitted, @command{guix refresh} uses
9067 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9068 signing keys. OpenPGP signatures are checked against keys from this keyring;
9069 missing keys are downloaded to this keyring as well (see
9070 @option{--key-download} below.)
9072 You can export keys from your default GPG keyring into a keybox file using
9073 commands like this one:
9076 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9079 Likewise, you can fetch keys to a specific keybox file like this:
9082 gpg --no-default-keyring --keyring mykeyring.kbx \
9083 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9086 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9087 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9089 @item --key-download=@var{policy}
9090 Handle missing OpenPGP keys according to @var{policy}, which may be one
9095 Always download missing OpenPGP keys from the key server, and add them
9096 to the user's GnuPG keyring.
9099 Never try to download missing OpenPGP keys. Instead just bail out.
9102 When a package signed with an unknown OpenPGP key is encountered, ask
9103 the user whether to download it or not. This is the default behavior.
9106 @item --key-server=@var{host}
9107 Use @var{host} as the OpenPGP key server when importing a public key.
9111 The @code{github} updater uses the
9112 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9113 releases. When used repeatedly e.g.@: when refreshing all packages,
9114 GitHub will eventually refuse to answer any further API requests. By
9115 default 60 API requests per hour are allowed, and a full refresh on all
9116 GitHub packages in Guix requires more than this. Authentication with
9117 GitHub through the use of an API token alleviates these limits. To use
9118 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9119 token procured from @uref{https://github.com/settings/tokens} or
9123 @node Invoking guix lint
9124 @section Invoking @command{guix lint}
9126 @cindex @command{guix lint}
9127 @cindex package, checking for errors
9128 The @command{guix lint} command is meant to help package developers avoid
9129 common errors and use a consistent style. It runs a number of checks on
9130 a given set of packages in order to find common mistakes in their
9131 definitions. Available @dfn{checkers} include (see
9132 @code{--list-checkers} for a complete list):
9137 Validate certain typographical and stylistic rules about package
9138 descriptions and synopses.
9140 @item inputs-should-be-native
9141 Identify inputs that should most likely be native inputs.
9147 @itemx source-file-name
9148 Probe @code{home-page} and @code{source} URLs and report those that are
9149 invalid. Suggest a @code{mirror://} URL when applicable. If the
9150 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9151 URL. Check that the source file name is meaningful, e.g.@: is not just a
9152 version number or ``git-checkout'', without a declared @code{file-name}
9153 (@pxref{origin Reference}).
9155 @item source-unstable-tarball
9156 Parse the @code{source} URL to determine if a tarball from GitHub is
9157 autogenerated or if it is a release tarball. Unfortunately GitHub's
9158 autogenerated tarballs are sometimes regenerated.
9161 @cindex security vulnerabilities
9162 @cindex CVE, Common Vulnerabilities and Exposures
9163 Report known vulnerabilities found in the Common Vulnerabilities and
9164 Exposures (CVE) databases of the current and past year
9165 @uref{https://nvd.nist.gov/download.cfm#CVE_FEED, published by the US
9168 To view information about a particular vulnerability, visit pages such as:
9172 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9174 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9178 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9179 @code{CVE-2015-7554}.
9181 Package developers can specify in package recipes the
9182 @uref{https://nvd.nist.gov/cpe.cfm,Common Platform Enumeration (CPE)}
9183 name and version of the package when they differ from the name or version
9184 that Guix uses, as in this example:
9190 ;; CPE calls this package "grub2".
9191 (properties '((cpe-name . "grub2")
9192 (cpe-version . "2.3")))
9195 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9196 Some entries in the CVE database do not specify which version of a
9197 package they apply to, and would thus ``stick around'' forever. Package
9198 developers who found CVE alerts and verified they can be ignored can
9199 declare them as in this example:
9205 ;; These CVEs no longer apply and can be safely ignored.
9206 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9209 "CVE-2011-5244")))))
9213 Warn about obvious source code formatting issues: trailing white space,
9214 use of tabulations, etc.
9217 The general syntax is:
9220 guix lint @var{options} @var{package}@dots{}
9223 If no package is given on the command line, then all packages are checked.
9224 The @var{options} may be zero or more of the following:
9227 @item --list-checkers
9229 List and describe all the available checkers that will be run on packages
9234 Only enable the checkers specified in a comma-separated list using the
9235 names returned by @code{--list-checkers}.
9239 @node Invoking guix size
9240 @section Invoking @command{guix size}
9243 @cindex package size
9245 @cindex @command{guix size}
9246 The @command{guix size} command helps package developers profile the
9247 disk usage of packages. It is easy to overlook the impact of an
9248 additional dependency added to a package, or the impact of using a
9249 single output for a package that could easily be split (@pxref{Packages
9250 with Multiple Outputs}). Such are the typical issues that
9251 @command{guix size} can highlight.
9253 The command can be passed one or more package specifications
9254 such as @code{gcc@@4.8}
9255 or @code{guile:debug}, or a file name in the store. Consider this
9259 $ guix size coreutils
9260 store item total self
9261 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9262 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9263 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9264 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9265 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9266 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9267 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9268 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9273 The store items listed here constitute the @dfn{transitive closure} of
9274 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9275 would be returned by:
9278 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9281 Here the output shows three columns next to store items. The first column,
9282 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9283 the store item---that is, its own size plus the size of all its
9284 dependencies. The next column, labeled ``self'', shows the size of the
9285 item itself. The last column shows the ratio of the size of the item
9286 itself to the space occupied by all the items listed here.
9288 In this example, we see that the closure of Coreutils weighs in at
9289 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9290 libraries. (That libc and GCC's libraries represent a large fraction of
9291 the closure is not a problem @i{per se} because they are always available
9292 on the system anyway.)
9294 When the package(s) passed to @command{guix size} are available in the
9295 store@footnote{More precisely, @command{guix size} looks for the
9296 @emph{ungrafted} variant of the given package(s), as returned by
9297 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9298 for information on grafts.}, @command{guix size} queries the daemon to determine its
9299 dependencies, and measures its size in the store, similar to @command{du
9300 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9303 When the given packages are @emph{not} in the store, @command{guix size}
9304 reports information based on the available substitutes
9305 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9306 store items that are not even on disk, only available remotely.
9308 You can also specify several package names:
9311 $ guix size coreutils grep sed bash
9312 store item total self
9313 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9314 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9315 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9316 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9322 In this example we see that the combination of the four packages takes
9323 102.3@tie{}MiB in total, which is much less than the sum of each closure
9324 since they have a lot of dependencies in common.
9326 The available options are:
9330 @item --substitute-urls=@var{urls}
9331 Use substitute information from @var{urls}.
9332 @xref{client-substitute-urls, the same option for @code{guix build}}.
9334 @item --sort=@var{key}
9335 Sort lines according to @var{key}, one of the following options:
9339 the size of each item (the default);
9341 the total size of the item's closure.
9344 @item --map-file=@var{file}
9345 Write a graphical map of disk usage in PNG format to @var{file}.
9347 For the example above, the map looks like this:
9349 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
9350 produced by @command{guix size}}
9352 This option requires that
9353 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
9354 installed and visible in Guile's module search path. When that is not
9355 the case, @command{guix size} fails as it tries to load it.
9357 @item --system=@var{system}
9358 @itemx -s @var{system}
9359 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
9363 @node Invoking guix graph
9364 @section Invoking @command{guix graph}
9367 @cindex @command{guix graph}
9368 @cindex package dependencies
9369 Packages and their dependencies form a @dfn{graph}, specifically a
9370 directed acyclic graph (DAG). It can quickly become difficult to have a
9371 mental model of the package DAG, so the @command{guix graph} command
9372 provides a visual representation of the DAG. By default,
9373 @command{guix graph} emits a DAG representation in the input format of
9374 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
9375 directly to the @command{dot} command of Graphviz. It can also emit an
9376 HTML page with embedded JavaScript code to display a ``chord diagram''
9377 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
9378 emit Cypher queries to construct a graph in a graph database supporting
9379 the @uref{https://www.opencypher.org/, openCypher} query language.
9380 The general syntax is:
9383 guix graph @var{options} @var{package}@dots{}
9386 For example, the following command generates a PDF file representing the
9387 package DAG for the GNU@tie{}Core Utilities, showing its build-time
9391 guix graph coreutils | dot -Tpdf > dag.pdf
9394 The output looks like this:
9396 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
9398 Nice little graph, no?
9400 But there is more than one graph! The one above is concise: it is the
9401 graph of package objects, omitting implicit inputs such as GCC, libc,
9402 grep, etc. It is often useful to have such a concise graph, but
9403 sometimes one may want to see more details. @command{guix graph} supports
9404 several types of graphs, allowing you to choose the level of detail:
9408 This is the default type used in the example above. It shows the DAG of
9409 package objects, excluding implicit dependencies. It is concise, but
9410 filters out many details.
9412 @item reverse-package
9413 This shows the @emph{reverse} DAG of packages. For example:
9416 guix graph --type=reverse-package ocaml
9419 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
9420 you are also interested in cases where OCaml is an implicit dependency, see
9421 @code{reverse-bag} below.)
9423 Note that for core packages this can yield huge graphs. If all you want
9424 is to know the number of packages that depend on a given package, use
9425 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
9426 @option{--list-dependent}}).
9429 This is the package DAG, @emph{including} implicit inputs.
9431 For instance, the following command:
9434 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
9437 ...@: yields this bigger graph:
9439 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
9441 At the bottom of the graph, we see all the implicit inputs of
9442 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
9444 Now, note that the dependencies of these implicit inputs---that is, the
9445 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
9446 here, for conciseness.
9449 Similar to @code{bag-emerged}, but this time including all the bootstrap
9452 @item bag-with-origins
9453 Similar to @code{bag}, but also showing origins and their dependencies.
9456 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
9457 it also takes implicit dependencies into account. For example:
9460 guix graph -t reverse-bag dune
9464 ...@: yields the graph of all packages that depend on Dune, directly or
9465 indirectly. Since Dune is an @emph{implicit} dependency of many packages
9466 @i{via} @code{dune-build-system}, this shows a large number of packages,
9467 whereas @code{reverse-package} would show very few if any.
9470 This is the most detailed representation: It shows the DAG of
9471 derivations (@pxref{Derivations}) and plain store items. Compared to
9472 the above representation, many additional nodes are visible, including
9473 build scripts, patches, Guile modules, etc.
9475 For this type of graph, it is also possible to pass a @file{.drv} file
9476 name instead of a package name, as in:
9479 guix graph -t derivation `guix system build -d my-config.scm`
9483 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
9484 For example, the following command shows the graph for the package
9485 module that defines the @code{guile} package:
9488 guix graph -t module guile | dot -Tpdf > module-graph.pdf
9492 All the types above correspond to @emph{build-time dependencies}. The
9493 following graph type represents the @emph{run-time dependencies}:
9497 This is the graph of @dfn{references} of a package output, as returned
9498 by @command{guix gc --references} (@pxref{Invoking guix gc}).
9500 If the given package output is not available in the store, @command{guix
9501 graph} attempts to obtain dependency information from substitutes.
9503 Here you can also pass a store file name instead of a package name. For
9504 example, the command below produces the reference graph of your profile
9505 (which can be big!):
9508 guix graph -t references `readlink -f ~/.guix-profile`
9512 This is the graph of the @dfn{referrers} of a store item, as returned by
9513 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
9515 This relies exclusively on local information from your store. For
9516 instance, let us suppose that the current Inkscape is available in 10
9517 profiles on your machine; @command{guix graph -t referrers inkscape}
9518 will show a graph rooted at Inkscape and with those 10 profiles linked
9521 It can help determine what is preventing a store item from being garbage
9526 The available options are the following:
9529 @item --type=@var{type}
9530 @itemx -t @var{type}
9531 Produce a graph output of @var{type}, where @var{type} must be one of
9532 the values listed above.
9535 List the supported graph types.
9537 @item --backend=@var{backend}
9538 @itemx -b @var{backend}
9539 Produce a graph using the selected @var{backend}.
9541 @item --list-backends
9542 List the supported graph backends.
9544 Currently, the available backends are Graphviz and d3.js.
9546 @item --expression=@var{expr}
9547 @itemx -e @var{expr}
9548 Consider the package @var{expr} evaluates to.
9550 This is useful to precisely refer to a package, as in this example:
9553 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
9556 @item --system=@var{system}
9557 @itemx -s @var{system}
9558 Display the graph for @var{system}---e.g., @code{i686-linux}.
9560 The package dependency graph is largely architecture-independent, but there
9561 are some architecture-dependent bits that this option allows you to visualize.
9566 @node Invoking guix publish
9567 @section Invoking @command{guix publish}
9569 @cindex @command{guix publish}
9570 The purpose of @command{guix publish} is to enable users to easily share
9571 their store with others, who can then use it as a substitute server
9572 (@pxref{Substitutes}).
9574 When @command{guix publish} runs, it spawns an HTTP server which allows
9575 anyone with network access to obtain substitutes from it. This means
9576 that any machine running Guix can also act as if it were a build farm,
9577 since the HTTP interface is compatible with Hydra, the software behind
9578 the @code{@value{SUBSTITUTE-SERVER}} build farm.
9580 For security, each substitute is signed, allowing recipients to check
9581 their authenticity and integrity (@pxref{Substitutes}). Because
9582 @command{guix publish} uses the signing key of the system, which is only
9583 readable by the system administrator, it must be started as root; the
9584 @code{--user} option makes it drop root privileges early on.
9586 The signing key pair must be generated before @command{guix publish} is
9587 launched, using @command{guix archive --generate-key} (@pxref{Invoking
9590 The general syntax is:
9593 guix publish @var{options}@dots{}
9596 Running @command{guix publish} without any additional arguments will
9597 spawn an HTTP server on port 8080:
9603 Once a publishing server has been authorized (@pxref{Invoking guix
9604 archive}), the daemon may download substitutes from it:
9607 guix-daemon --substitute-urls=http://example.org:8080
9610 By default, @command{guix publish} compresses archives on the fly as it
9611 serves them. This ``on-the-fly'' mode is convenient in that it requires
9612 no setup and is immediately available. However, when serving lots of
9613 clients, we recommend using the @option{--cache} option, which enables
9614 caching of the archives before they are sent to clients---see below for
9615 details. The @command{guix weather} command provides a handy way to
9616 check what a server provides (@pxref{Invoking guix weather}).
9618 As a bonus, @command{guix publish} also serves as a content-addressed
9619 mirror for source files referenced in @code{origin} records
9620 (@pxref{origin Reference}). For instance, assuming @command{guix
9621 publish} is running on @code{example.org}, the following URL returns the
9622 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
9623 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
9626 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
9629 Obviously, these URLs only work for files that are in the store; in
9630 other cases, they return 404 (``Not Found'').
9632 @cindex build logs, publication
9633 Build logs are available from @code{/log} URLs like:
9636 http://example.org/log/gwspk@dots{}-guile-2.2.3
9640 When @command{guix-daemon} is configured to save compressed build logs,
9641 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
9642 URLs return the compressed log as-is, with an appropriate
9643 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
9644 running @command{guix-daemon} with @code{--log-compression=gzip} since
9645 Web browsers can automatically decompress it, which is not the case with
9648 The following options are available:
9651 @item --port=@var{port}
9652 @itemx -p @var{port}
9653 Listen for HTTP requests on @var{port}.
9655 @item --listen=@var{host}
9656 Listen on the network interface for @var{host}. The default is to
9657 accept connections from any interface.
9659 @item --user=@var{user}
9660 @itemx -u @var{user}
9661 Change privileges to @var{user} as soon as possible---i.e., once the
9662 server socket is open and the signing key has been read.
9664 @item --compression[=@var{method}[:@var{level}]]
9665 @itemx -C [@var{method}[:@var{level}]]
9666 Compress data using the given @var{method} and @var{level}. @var{method} is
9667 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
9670 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
9671 to different compression levels: 1 is the fastest, and 9 is the best
9672 (CPU-intensive). The default is 3.
9674 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
9675 increase in CPU usage; see
9676 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
9679 Unless @option{--cache} is used, compression occurs on the fly and
9680 the compressed streams are not
9681 cached. Thus, to reduce load on the machine that runs @command{guix
9682 publish}, it may be a good idea to choose a low compression level, to
9683 run @command{guix publish} behind a caching proxy, or to use
9684 @option{--cache}. Using @option{--cache} has the advantage that it
9685 allows @command{guix publish} to add @code{Content-Length} HTTP header
9688 This option can be repeated, in which case every substitute gets compressed
9689 using all the selected methods, and all of them are advertised. This is
9690 useful when users may not support all the compression methods: they can select
9691 the one they support.
9693 @item --cache=@var{directory}
9694 @itemx -c @var{directory}
9695 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
9696 and only serve archives that are in cache.
9698 When this option is omitted, archives and meta-data are created
9699 on-the-fly. This can reduce the available bandwidth, especially when
9700 compression is enabled, since this may become CPU-bound. Another
9701 drawback of the default mode is that the length of archives is not known
9702 in advance, so @command{guix publish} does not add a
9703 @code{Content-Length} HTTP header to its responses, which in turn
9704 prevents clients from knowing the amount of data being downloaded.
9706 Conversely, when @option{--cache} is used, the first request for a store
9707 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
9708 background process to @dfn{bake} the archive---computing its
9709 @code{.narinfo} and compressing the archive, if needed. Once the
9710 archive is cached in @var{directory}, subsequent requests succeed and
9711 are served directly from the cache, which guarantees that clients get
9712 the best possible bandwidth.
9714 The ``baking'' process is performed by worker threads. By default, one
9715 thread per CPU core is created, but this can be customized. See
9716 @option{--workers} below.
9718 When @option{--ttl} is used, cached entries are automatically deleted
9719 when they have expired.
9721 @item --workers=@var{N}
9722 When @option{--cache} is used, request the allocation of @var{N} worker
9723 threads to ``bake'' archives.
9725 @item --ttl=@var{ttl}
9726 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
9727 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
9728 days, @code{1m} means 1 month, and so on.
9730 This allows the user's Guix to keep substitute information in cache for
9731 @var{ttl}. However, note that @code{guix publish} does not itself
9732 guarantee that the store items it provides will indeed remain available
9733 for as long as @var{ttl}.
9735 Additionally, when @option{--cache} is used, cached entries that have
9736 not been accessed for @var{ttl} and that no longer have a corresponding
9737 item in the store, may be deleted.
9739 @item --nar-path=@var{path}
9740 Use @var{path} as the prefix for the URLs of ``nar'' files
9741 (@pxref{Invoking guix archive, normalized archives}).
9743 By default, nars are served at a URL such as
9744 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
9745 change the @code{/nar} part to @var{path}.
9747 @item --public-key=@var{file}
9748 @itemx --private-key=@var{file}
9749 Use the specific @var{file}s as the public/private key pair used to sign
9750 the store items being published.
9752 The files must correspond to the same key pair (the private key is used
9753 for signing and the public key is merely advertised in the signature
9754 metadata). They must contain keys in the canonical s-expression format
9755 as produced by @command{guix archive --generate-key} (@pxref{Invoking
9756 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
9757 @file{/etc/guix/signing-key.sec} are used.
9759 @item --repl[=@var{port}]
9760 @itemx -r [@var{port}]
9761 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
9762 Reference Manual}) on @var{port} (37146 by default). This is used
9763 primarily for debugging a running @command{guix publish} server.
9766 Enabling @command{guix publish} on Guix System is a one-liner: just
9767 instantiate a @code{guix-publish-service-type} service in the @code{services} field
9768 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
9769 @code{guix-publish-service-type}}).
9771 If you are instead running Guix on a ``foreign distro'', follow these
9776 If your host distro uses the systemd init system:
9779 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
9780 /etc/systemd/system/
9781 # systemctl start guix-publish && systemctl enable guix-publish
9785 If your host distro uses the Upstart init system:
9788 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
9789 # start guix-publish
9793 Otherwise, proceed similarly with your distro's init system.
9796 @node Invoking guix challenge
9797 @section Invoking @command{guix challenge}
9799 @cindex reproducible builds
9800 @cindex verifiable builds
9801 @cindex @command{guix challenge}
9803 Do the binaries provided by this server really correspond to the source
9804 code it claims to build? Is a package build process deterministic?
9805 These are the questions the @command{guix challenge} command attempts to
9808 The former is obviously an important question: Before using a substitute
9809 server (@pxref{Substitutes}), one had better @emph{verify} that it
9810 provides the right binaries, and thus @emph{challenge} it. The latter
9811 is what enables the former: If package builds are deterministic, then
9812 independent builds of the package should yield the exact same result,
9813 bit for bit; if a server provides a binary different from the one
9814 obtained locally, it may be either corrupt or malicious.
9816 We know that the hash that shows up in @file{/gnu/store} file names is
9817 the hash of all the inputs of the process that built the file or
9818 directory---compilers, libraries, build scripts,
9819 etc. (@pxref{Introduction}). Assuming deterministic build processes,
9820 one store file name should map to exactly one build output.
9821 @command{guix challenge} checks whether there is, indeed, a single
9822 mapping by comparing the build outputs of several independent builds of
9823 any given store item.
9825 The command output looks like this:
9828 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
9829 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
9830 updating list of substitutes from 'https://guix.example.org'... 100.0%
9831 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
9832 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9833 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9834 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
9835 /gnu/store/@dots{}-git-2.5.0 contents differ:
9836 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
9837 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
9838 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
9839 /gnu/store/@dots{}-pius-2.1.1 contents differ:
9840 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9841 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9842 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
9846 6,406 store items were analyzed:
9847 - 4,749 (74.1%) were identical
9848 - 525 (8.2%) differed
9849 - 1,132 (17.7%) were inconclusive
9853 In this example, @command{guix challenge} first scans the store to
9854 determine the set of locally-built derivations---as opposed to store
9855 items that were downloaded from a substitute server---and then queries
9856 all the substitute servers. It then reports those store items for which
9857 the servers obtained a result different from the local build.
9859 @cindex non-determinism, in package builds
9860 As an example, @code{guix.example.org} always gets a different answer.
9861 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
9862 case of Git. This might indicate that the build process of Git is
9863 non-deterministic, meaning that its output varies as a function of
9864 various things that Guix does not fully control, in spite of building
9865 packages in isolated environments (@pxref{Features}). Most common
9866 sources of non-determinism include the addition of timestamps in build
9867 results, the inclusion of random numbers, and directory listings sorted
9868 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
9871 To find out what is wrong with this Git binary, we can do something along
9872 these lines (@pxref{Invoking guix archive}):
9875 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0 \
9876 | guix archive -x /tmp/git
9877 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
9880 This command shows the difference between the files resulting from the
9881 local build, and the files resulting from the build on
9882 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
9883 diffutils, Comparing and Merging Files}). The @command{diff} command
9884 works great for text files. When binary files differ, a better option
9885 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
9886 visualize differences for all kinds of files.
9888 Once you have done that work, you can tell whether the differences are due
9889 to a non-deterministic build process or to a malicious server. We try
9890 hard to remove sources of non-determinism in packages to make it easier
9891 to verify substitutes, but of course, this is a process that
9892 involves not just Guix, but a large part of the free software community.
9893 In the meantime, @command{guix challenge} is one tool to help address
9896 If you are writing packages for Guix, you are encouraged to check
9897 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
9898 same build result as you did with:
9901 $ guix challenge @var{package}
9905 where @var{package} is a package specification such as
9906 @code{guile@@2.0} or @code{glibc:debug}.
9908 The general syntax is:
9911 guix challenge @var{options} [@var{packages}@dots{}]
9914 When a difference is found between the hash of a locally-built item and
9915 that of a server-provided substitute, or among substitutes provided by
9916 different servers, the command displays it as in the example above and
9917 its exit code is 2 (other non-zero exit codes denote other kinds of
9920 The one option that matters is:
9924 @item --substitute-urls=@var{urls}
9925 Consider @var{urls} the whitespace-separated list of substitute source
9930 Show details about matches (identical contents) in addition to
9931 information about mismatches.
9935 @node Invoking guix copy
9936 @section Invoking @command{guix copy}
9938 @cindex copy, of store items, over SSH
9939 @cindex SSH, copy of store items
9940 @cindex sharing store items across machines
9941 @cindex transferring store items across machines
9942 The @command{guix copy} command copies items from the store of one
9943 machine to that of another machine over a secure shell (SSH)
9944 connection@footnote{This command is available only when Guile-SSH was
9945 found. @xref{Requirements}, for details.}. For example, the following
9946 command copies the @code{coreutils} package, the user's profile, and all
9947 their dependencies over to @var{host}, logged in as @var{user}:
9950 guix copy --to=@var{user}@@@var{host} \
9951 coreutils `readlink -f ~/.guix-profile`
9954 If some of the items to be copied are already present on @var{host},
9955 they are not actually sent.
9957 The command below retrieves @code{libreoffice} and @code{gimp} from
9958 @var{host}, assuming they are available there:
9961 guix copy --from=@var{host} libreoffice gimp
9964 The SSH connection is established using the Guile-SSH client, which is
9965 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
9966 @file{~/.ssh/config}, and uses the SSH agent for authentication.
9968 The key used to sign items that are sent must be accepted by the remote
9969 machine. Likewise, the key used by the remote machine to sign items you
9970 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
9971 own daemon. @xref{Invoking guix archive}, for more information about
9972 store item authentication.
9974 The general syntax is:
9977 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
9980 You must always specify one of the following options:
9983 @item --to=@var{spec}
9984 @itemx --from=@var{spec}
9985 Specify the host to send to or receive from. @var{spec} must be an SSH
9986 spec such as @code{example.org}, @code{charlie@@example.org}, or
9987 @code{charlie@@example.org:2222}.
9990 The @var{items} can be either package names, such as @code{gimp}, or
9991 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
9993 When specifying the name of a package to send, it is first built if
9994 needed, unless @option{--dry-run} was specified. Common build options
9995 are supported (@pxref{Common Build Options}).
9998 @node Invoking guix container
9999 @section Invoking @command{guix container}
10001 @cindex @command{guix container}
10003 As of version @value{VERSION}, this tool is experimental. The interface
10004 is subject to radical change in the future.
10007 The purpose of @command{guix container} is to manipulate processes
10008 running within an isolated environment, commonly known as a
10009 ``container'', typically created by the @command{guix environment}
10010 (@pxref{Invoking guix environment}) and @command{guix system container}
10011 (@pxref{Invoking guix system}) commands.
10013 The general syntax is:
10016 guix container @var{action} @var{options}@dots{}
10019 @var{action} specifies the operation to perform with a container, and
10020 @var{options} specifies the context-specific arguments for the action.
10022 The following actions are available:
10026 Execute a command within the context of a running container.
10031 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10034 @var{pid} specifies the process ID of the running container.
10035 @var{program} specifies an executable file name within the root file
10036 system of the container. @var{arguments} are the additional options that
10037 will be passed to @var{program}.
10039 The following command launches an interactive login shell inside a
10040 Guix system container, started by @command{guix system container}, and whose
10041 process ID is 9001:
10044 guix container exec 9001 /run/current-system/profile/bin/bash --login
10047 Note that the @var{pid} cannot be the parent process of a container. It
10048 must be PID 1 of the container or one of its child processes.
10052 @node Invoking guix weather
10053 @section Invoking @command{guix weather}
10055 Occasionally you're grumpy because substitutes are lacking and you end
10056 up building packages by yourself (@pxref{Substitutes}). The
10057 @command{guix weather} command reports on substitute availability on the
10058 specified servers so you can have an idea of whether you'll be grumpy
10059 today. It can sometimes be useful info as a user, but it is primarily
10060 useful to people running @command{guix publish} (@pxref{Invoking guix
10063 @cindex statistics, for substitutes
10064 @cindex availability of substitutes
10065 @cindex substitute availability
10066 @cindex weather, substitute availability
10067 Here's a sample run:
10070 $ guix weather --substitute-urls=https://guix.example.org
10071 computing 5,872 package derivations for x86_64-linux...
10072 looking for 6,128 store items on https://guix.example.org..
10073 updating list of substitutes from 'https://guix.example.org'... 100.0%
10074 https://guix.example.org
10075 43.4% substitutes available (2,658 out of 6,128)
10076 7,032.5 MiB of nars (compressed)
10077 19,824.2 MiB on disk (uncompressed)
10078 0.030 seconds per request (182.9 seconds in total)
10079 33.5 requests per second
10081 9.8% (342 out of 3,470) of the missing items are queued
10083 x86_64-linux: 518 (59.7%)
10084 i686-linux: 221 (25.5%)
10085 aarch64-linux: 128 (14.8%)
10086 build rate: 23.41 builds per hour
10087 x86_64-linux: 11.16 builds per hour
10088 i686-linux: 6.03 builds per hour
10089 aarch64-linux: 6.41 builds per hour
10092 @cindex continuous integration, statistics
10093 As you can see, it reports the fraction of all the packages for which
10094 substitutes are available on the server---regardless of whether
10095 substitutes are enabled, and regardless of whether this server's signing
10096 key is authorized. It also reports the size of the compressed archives
10097 (``nars'') provided by the server, the size the corresponding store
10098 items occupy in the store (assuming deduplication is turned off), and
10099 the server's throughput. The second part gives continuous integration
10100 (CI) statistics, if the server supports it. In addition, using the
10101 @option{--coverage} option, @command{guix weather} can list ``important''
10102 package substitutes missing on the server (see below).
10104 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10105 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10106 challenge}, it ignores signatures on those substitutes, which is
10107 innocuous since the command only gathers statistics and cannot install
10110 The general syntax is:
10113 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10116 When @var{packages} is omitted, @command{guix weather} checks the availability
10117 of substitutes for @emph{all} the packages, or for those specified with
10118 @option{--manifest}; otherwise it only considers the specified packages. It
10119 is also possible to query specific system types with @option{--system}. The
10120 available options are listed below.
10123 @item --substitute-urls=@var{urls}
10124 @var{urls} is the space-separated list of substitute server URLs to
10125 query. When this option is omitted, the default set of substitute
10126 servers is queried.
10128 @item --system=@var{system}
10129 @itemx -s @var{system}
10130 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10131 option can be repeated, in which case @command{guix weather} will query
10132 substitutes for several system types.
10134 @item --manifest=@var{file}
10135 Instead of querying substitutes for all the packages, only ask for those
10136 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10137 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10140 @item --coverage[=@var{count}]
10141 @itemx -c [@var{count}]
10142 Report on substitute coverage for packages: list packages with at least
10143 @var{count} dependents (zero by default) for which substitutes are
10144 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10145 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10146 @var{b} usually lacks substitutes as well. The result looks like this:
10149 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10150 computing 8,983 package derivations for x86_64-linux...
10151 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10152 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10153 @value{SUBSTITUTE-URL}
10154 64.7% substitutes available (6,047 out of 9,343)
10156 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10157 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10158 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10159 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10163 What this example shows is that @code{kcoreaddons} and presumably the 58
10164 packages that depend on it have no substitutes at @code{ci.guix.info};
10165 likewise for @code{qgpgme} and the 46 packages that depend on it.
10167 If you are a Guix developer, or if you are taking care of this build farm,
10168 you'll probably want to have a closer look at these packages: they may simply
10172 @node Invoking guix processes
10173 @section Invoking @command{guix processes}
10175 The @command{guix processes} command can be useful to developers and system
10176 administrators, especially on multi-user machines and on build farms: it lists
10177 the current sessions (connections to the daemon), as well as information about
10178 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10179 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10180 listed.}. Here's an example of the information it returns:
10183 $ sudo guix processes
10186 ClientCommand: guix environment --ad-hoc python
10190 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10194 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10195 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10196 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10197 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10198 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10199 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10200 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10203 In this example we see that @command{guix-daemon} has three clients:
10204 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10205 integration tool; their process identifier (PID) is given by the
10206 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10207 @command{guix-daemon} sub-process of this particular session.
10209 The @code{LockHeld} fields show which store items are currently locked by this
10210 session, which corresponds to store items being built or substituted (the
10211 @code{LockHeld} field is not displayed when @command{guix processes} is not
10212 running as root.) Last, by looking at the @code{ChildProcess} field, we
10213 understand that these three builds are being offloaded (@pxref{Daemon Offload
10216 The output is in Recutils format so we can use the handy @command{recsel}
10217 command to select sessions of interest (@pxref{Selection Expressions,,,
10218 recutils, GNU recutils manual}). As an example, the command shows the command
10219 line and PID of the client that triggered the build of a Perl package:
10222 $ sudo guix processes | \
10223 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10225 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10229 @node System Configuration
10230 @chapter System Configuration
10232 @cindex system configuration
10233 Guix System supports a consistent whole-system configuration
10234 mechanism. By that we mean that all aspects of the global system
10235 configuration---such as the available system services, timezone and
10236 locale settings, user accounts---are declared in a single place. Such
10237 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10239 One of the advantages of putting all the system configuration under the
10240 control of Guix is that it supports transactional system upgrades, and
10241 makes it possible to roll back to a previous system instantiation,
10242 should something go wrong with the new one (@pxref{Features}). Another
10243 advantage is that it makes it easy to replicate the exact same configuration
10244 across different machines, or at different points in time, without
10245 having to resort to additional administration tools layered on top of
10246 the own tools of the system.
10247 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10249 This section describes this mechanism. First we focus on the system
10250 administrator's viewpoint---explaining how the system is configured and
10251 instantiated. Then we show how this mechanism can be extended, for
10252 instance to support new system services.
10255 * Using the Configuration System:: Customizing your GNU system.
10256 * operating-system Reference:: Detail of operating-system declarations.
10257 * File Systems:: Configuring file system mounts.
10258 * Mapped Devices:: Block device extra processing.
10259 * User Accounts:: Specifying user accounts.
10260 * Keyboard Layout:: How the system interprets key strokes.
10261 * Locales:: Language and cultural convention settings.
10262 * Services:: Specifying system services.
10263 * Setuid Programs:: Programs running with root privileges.
10264 * X.509 Certificates:: Authenticating HTTPS servers.
10265 * Name Service Switch:: Configuring libc's name service switch.
10266 * Initial RAM Disk:: Linux-Libre bootstrapping.
10267 * Bootloader Configuration:: Configuring the boot loader.
10268 * Invoking guix system:: Instantiating a system configuration.
10269 * Running Guix in a VM:: How to run Guix System in a virtual machine.
10270 * Defining Services:: Adding new service definitions.
10273 @node Using the Configuration System
10274 @section Using the Configuration System
10276 The operating system is configured by providing an
10277 @code{operating-system} declaration in a file that can then be passed to
10278 the @command{guix system} command (@pxref{Invoking guix system}). A
10279 simple setup, with the default system services, the default Linux-Libre
10280 kernel, initial RAM disk, and boot loader looks like this:
10282 @findex operating-system
10284 @include os-config-bare-bones.texi
10287 This example should be self-describing. Some of the fields defined
10288 above, such as @code{host-name} and @code{bootloader}, are mandatory.
10289 Others, such as @code{packages} and @code{services}, can be omitted, in
10290 which case they get a default value.
10292 Below we discuss the effect of some of the most important fields
10293 (@pxref{operating-system Reference}, for details about all the available
10294 fields), and how to @dfn{instantiate} the operating system using
10295 @command{guix system}.
10297 @unnumberedsubsec Bootloader
10299 @cindex legacy boot, on Intel machines
10300 @cindex BIOS boot, on Intel machines
10303 The @code{bootloader} field describes the method that will be used to boot
10304 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
10305 mode, as in the example above. However, more recent machines rely instead on
10306 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
10307 the @code{bootloader} field should contain something along these lines:
10310 (bootloader-configuration
10311 (bootloader grub-efi-bootloader)
10312 (target "/boot/efi"))
10315 @xref{Bootloader Configuration}, for more information on the available
10316 configuration options.
10318 @unnumberedsubsec Globally-Visible Packages
10320 @vindex %base-packages
10321 The @code{packages} field lists packages that will be globally visible
10322 on the system, for all user accounts---i.e., in every user's @code{PATH}
10323 environment variable---in addition to the per-user profiles
10324 (@pxref{Invoking guix package}). The @var{%base-packages} variable
10325 provides all the tools one would expect for basic user and administrator
10326 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
10327 the GNU Zile lightweight text editor, @command{find}, @command{grep},
10328 etc. The example above adds GNU@tie{}Screen to those,
10329 taken from the @code{(gnu packages screen)}
10330 module (@pxref{Package Modules}). The
10331 @code{(list package output)} syntax can be used to add a specific output
10335 (use-modules (gnu packages))
10336 (use-modules (gnu packages dns))
10340 (packages (cons (list bind "utils")
10344 @findex specification->package
10345 Referring to packages by variable name, like @code{bind} above, has
10346 the advantage of being unambiguous; it also allows typos and such to be
10347 diagnosed right away as ``unbound variables''. The downside is that one
10348 needs to know which module defines which package, and to augment the
10349 @code{use-package-modules} line accordingly. To avoid that, one can use
10350 the @code{specification->package} procedure of the @code{(gnu packages)}
10351 module, which returns the best package for a given name or name and
10355 (use-modules (gnu packages))
10359 (packages (append (map specification->package
10360 '("tcpdump" "htop" "gnupg@@2.0"))
10364 @unnumberedsubsec System Services
10367 @vindex %base-services
10368 The @code{services} field lists @dfn{system services} to be made
10369 available when the system starts (@pxref{Services}).
10370 The @code{operating-system} declaration above specifies that, in
10371 addition to the basic services, we want the OpenSSH secure shell
10372 daemon listening on port 2222 (@pxref{Networking Services,
10373 @code{openssh-service-type}}). Under the hood,
10374 @code{openssh-service-type} arranges so that @command{sshd} is started with the
10375 right command-line options, possibly with supporting configuration files
10376 generated as needed (@pxref{Defining Services}).
10378 @cindex customization, of services
10379 @findex modify-services
10380 Occasionally, instead of using the base services as is, you will want to
10381 customize them. To do this, use @code{modify-services} (@pxref{Service
10382 Reference, @code{modify-services}}) to modify the list.
10384 For example, suppose you want to modify @code{guix-daemon} and Mingetty
10385 (the console log-in) in the @var{%base-services} list (@pxref{Base
10386 Services, @code{%base-services}}). To do that, you can write the
10387 following in your operating system declaration:
10390 (define %my-services
10391 ;; My very own list of services.
10392 (modify-services %base-services
10393 (guix-service-type config =>
10394 (guix-configuration
10396 (use-substitutes? #f)
10397 (extra-options '("--gc-keep-derivations"))))
10398 (mingetty-service-type config =>
10399 (mingetty-configuration
10400 (inherit config)))))
10404 (services %my-services))
10407 This changes the configuration---i.e., the service parameters---of the
10408 @code{guix-service-type} instance, and that of all the
10409 @code{mingetty-service-type} instances in the @var{%base-services} list.
10410 Observe how this is accomplished: first, we arrange for the original
10411 configuration to be bound to the identifier @code{config} in the
10412 @var{body}, and then we write the @var{body} so that it evaluates to the
10413 desired configuration. In particular, notice how we use @code{inherit}
10414 to create a new configuration which has the same values as the old
10415 configuration, but with a few modifications.
10417 @cindex encrypted disk
10418 The configuration for a typical ``desktop'' usage, with an encrypted
10419 root partition, the X11 display
10420 server, GNOME and Xfce (users can choose which of these desktop
10421 environments to use at the log-in screen by pressing @kbd{F1}), network
10422 management, power management, and more, would look like this:
10425 @include os-config-desktop.texi
10428 A graphical system with a choice of lightweight window managers
10429 instead of full-blown desktop environments would look like this:
10432 @include os-config-lightweight-desktop.texi
10435 This example refers to the @file{/boot/efi} file system by its UUID,
10436 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
10437 as returned by the @command{blkid} command.
10439 @xref{Desktop Services}, for the exact list of services provided by
10440 @var{%desktop-services}. @xref{X.509 Certificates}, for background
10441 information about the @code{nss-certs} package that is used here.
10443 Again, @var{%desktop-services} is just a list of service objects. If
10444 you want to remove services from there, you can do so using the
10445 procedures for list filtering (@pxref{SRFI-1 Filtering and
10446 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
10447 following expression returns a list that contains all the services in
10448 @var{%desktop-services} minus the Avahi service:
10451 (remove (lambda (service)
10452 (eq? (service-kind service) avahi-service-type))
10456 @unnumberedsubsec Instantiating the System
10458 Assuming the @code{operating-system} declaration
10459 is stored in the @file{my-system-config.scm}
10460 file, the @command{guix system reconfigure my-system-config.scm} command
10461 instantiates that configuration, and makes it the default GRUB boot
10462 entry (@pxref{Invoking guix system}).
10464 The normal way to change the system configuration is by updating this
10465 file and re-running @command{guix system reconfigure}. One should never
10466 have to touch files in @file{/etc} or to run commands that modify the
10467 system state such as @command{useradd} or @command{grub-install}. In
10468 fact, you must avoid that since that would not only void your warranty
10469 but also prevent you from rolling back to previous versions of your
10470 system, should you ever need to.
10472 @cindex roll-back, of the operating system
10473 Speaking of roll-back, each time you run @command{guix system
10474 reconfigure}, a new @dfn{generation} of the system is created---without
10475 modifying or deleting previous generations. Old system generations get
10476 an entry in the bootloader boot menu, allowing you to boot them in case
10477 something went wrong with the latest generation. Reassuring, no? The
10478 @command{guix system list-generations} command lists the system
10479 generations available on disk. It is also possible to roll back the
10480 system via the commands @command{guix system roll-back} and
10481 @command{guix system switch-generation}.
10483 Although the @command{guix system reconfigure} command will not modify
10484 previous generations, you must take care when the current generation is not
10485 the latest (e.g., after invoking @command{guix system roll-back}), since
10486 the operation might overwrite a later generation (@pxref{Invoking guix
10489 @unnumberedsubsec The Programming Interface
10491 At the Scheme level, the bulk of an @code{operating-system} declaration
10492 is instantiated with the following monadic procedure (@pxref{The Store
10495 @deffn {Monadic Procedure} operating-system-derivation os
10496 Return a derivation that builds @var{os}, an @code{operating-system}
10497 object (@pxref{Derivations}).
10499 The output of the derivation is a single directory that refers to all
10500 the packages, configuration files, and other supporting files needed to
10501 instantiate @var{os}.
10504 This procedure is provided by the @code{(gnu system)} module. Along
10505 with @code{(gnu services)} (@pxref{Services}), this module contains the
10506 guts of Guix System. Make sure to visit it!
10509 @node operating-system Reference
10510 @section @code{operating-system} Reference
10512 This section summarizes all the options available in
10513 @code{operating-system} declarations (@pxref{Using the Configuration
10516 @deftp {Data Type} operating-system
10517 This is the data type representing an operating system configuration.
10518 By that, we mean all the global system configuration, not per-user
10519 configuration (@pxref{Using the Configuration System}).
10522 @item @code{kernel} (default: @var{linux-libre})
10523 The package object of the operating system kernel to use@footnote{Currently
10524 only the Linux-libre kernel is supported. In the future, it will be
10525 possible to use the GNU@tie{}Hurd.}.
10527 @item @code{kernel-arguments} (default: @code{'("quiet")})
10528 List of strings or gexps representing additional arguments to pass on
10529 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
10531 @item @code{bootloader}
10532 The system bootloader configuration object. @xref{Bootloader Configuration}.
10535 This is the label (a string) as it appears in the bootloader's menu entry.
10536 The default label includes the kernel name and version.
10538 @item @code{keyboard-layout} (default: @code{#f})
10539 This field specifies the keyboard layout to use in the console. It can be
10540 either @code{#f}, in which case the default keyboard layout is used (usually
10541 US English), or a @code{<keyboard-layout>} record.
10543 This keyboard layout is in effect as soon as the kernel has booted. For
10544 instance, it is the keyboard layout in effect when you type a passphrase if
10545 your root file system is on a @code{luks-device-mapping} mapped device
10546 (@pxref{Mapped Devices}).
10549 This does @emph{not} specify the keyboard layout used by the bootloader, nor
10550 that used by the graphical display server. @xref{Bootloader Configuration},
10551 for information on how to specify the bootloader's keyboard layout. @xref{X
10552 Window}, for information on how to specify the keyboard layout used by the X
10556 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
10558 @cindex initial RAM disk
10559 The list of Linux kernel modules that need to be available in the
10560 initial RAM disk. @xref{Initial RAM Disk}.
10562 @item @code{initrd} (default: @code{base-initrd})
10563 A procedure that returns an initial RAM disk for the Linux
10564 kernel. This field is provided to support low-level customization and
10565 should rarely be needed for casual use. @xref{Initial RAM Disk}.
10567 @item @code{firmware} (default: @var{%base-firmware})
10569 List of firmware packages loadable by the operating system kernel.
10571 The default includes firmware needed for Atheros- and Broadcom-based
10572 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
10573 respectively). @xref{Hardware Considerations}, for more info on
10574 supported hardware.
10576 @item @code{host-name}
10579 @item @code{hosts-file}
10581 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
10582 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
10583 Reference Manual}). The default is a file with entries for
10584 @code{localhost} and @var{host-name}.
10586 @item @code{mapped-devices} (default: @code{'()})
10587 A list of mapped devices. @xref{Mapped Devices}.
10589 @item @code{file-systems}
10590 A list of file systems. @xref{File Systems}.
10592 @item @code{swap-devices} (default: @code{'()})
10593 @cindex swap devices
10594 A list of strings identifying devices or files to be used for ``swap
10595 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
10596 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
10597 It is possible to specify a swap file in a file system on a mapped
10598 device, provided that the necessary device mapping and file system are
10599 also specified. @xref{Mapped Devices} and @ref{File Systems}.
10601 @item @code{users} (default: @code{%base-user-accounts})
10602 @itemx @code{groups} (default: @var{%base-groups})
10603 List of user accounts and groups. @xref{User Accounts}.
10605 If the @code{users} list lacks a user account with UID@tie{}0, a
10606 ``root'' account with UID@tie{}0 is automatically added.
10608 @item @code{skeletons} (default: @code{(default-skeletons)})
10609 A list target file name/file-like object tuples (@pxref{G-Expressions,
10610 file-like objects}). These are the skeleton files that will be added to
10611 the home directory of newly-created user accounts.
10613 For instance, a valid value may look like this:
10616 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
10617 (".guile" ,(plain-file "guile"
10618 "(use-modules (ice-9 readline))
10619 (activate-readline)")))
10622 @item @code{issue} (default: @var{%default-issue})
10623 A string denoting the contents of the @file{/etc/issue} file, which is
10624 displayed when users log in on a text console.
10626 @item @code{packages} (default: @var{%base-packages})
10627 The set of packages installed in the global profile, which is accessible
10628 at @file{/run/current-system/profile}.
10630 The default set includes core utilities and it is good practice to
10631 install non-core utilities in user profiles (@pxref{Invoking guix
10634 @item @code{timezone}
10635 A timezone identifying string---e.g., @code{"Europe/Paris"}.
10637 You can run the @command{tzselect} command to find out which timezone
10638 string corresponds to your region. Choosing an invalid timezone name
10639 causes @command{guix system} to fail.
10641 @item @code{locale} (default: @code{"en_US.utf8"})
10642 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
10643 Library Reference Manual}). @xref{Locales}, for more information.
10645 @item @code{locale-definitions} (default: @var{%default-locale-definitions})
10646 The list of locale definitions to be compiled and that may be used at
10647 run time. @xref{Locales}.
10649 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
10650 The list of GNU@tie{}libc packages whose locale data and tools are used
10651 to build the locale definitions. @xref{Locales}, for compatibility
10652 considerations that justify this option.
10654 @item @code{name-service-switch} (default: @var{%default-nss})
10655 Configuration of the libc name service switch (NSS)---a
10656 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
10659 @item @code{services} (default: @var{%base-services})
10660 A list of service objects denoting system services. @xref{Services}.
10662 @cindex essential services
10663 @item @code{essential-services} (default: ...)
10664 The list of ``essential services''---i.e., things like instances of
10665 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
10666 Reference}), which are derived from the operating system definition itself.
10667 As a user you should @emph{never} need to touch this field.
10669 @item @code{pam-services} (default: @code{(base-pam-services)})
10671 @cindex pluggable authentication modules
10672 Linux @dfn{pluggable authentication module} (PAM) services.
10673 @c FIXME: Add xref to PAM services section.
10675 @item @code{setuid-programs} (default: @var{%setuid-programs})
10676 List of string-valued G-expressions denoting setuid programs.
10677 @xref{Setuid Programs}.
10679 @item @code{sudoers-file} (default: @var{%sudoers-specification})
10680 @cindex sudoers file
10681 The contents of the @file{/etc/sudoers} file as a file-like object
10682 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
10684 This file specifies which users can use the @command{sudo} command, what
10685 they are allowed to do, and what privileges they may gain. The default
10686 is that only @code{root} and members of the @code{wheel} group may use
10691 @deffn {Scheme Syntax} this-operating-system
10692 When used in the @emph{lexical scope} of an operating system field definition,
10693 this identifier resolves to the operating system being defined.
10695 The example below shows how to refer to the operating system being defined in
10696 the definition of the @code{label} field:
10699 (use-modules (gnu) (guix))
10703 (label (package-full-name
10704 (operating-system-kernel this-operating-system))))
10707 It is an error to refer to @code{this-operating-system} outside an operating
10714 @section File Systems
10716 The list of file systems to be mounted is specified in the
10717 @code{file-systems} field of the operating system declaration
10718 (@pxref{Using the Configuration System}). Each file system is declared
10719 using the @code{file-system} form, like this:
10723 (mount-point "/home")
10724 (device "/dev/sda3")
10728 As usual, some of the fields are mandatory---those shown in the example
10729 above---while others can be omitted. These are described below.
10731 @deftp {Data Type} file-system
10732 Objects of this type represent file systems to be mounted. They
10733 contain the following members:
10737 This is a string specifying the type of the file system---e.g.,
10740 @item @code{mount-point}
10741 This designates the place where the file system is to be mounted.
10743 @item @code{device}
10744 This names the ``source'' of the file system. It can be one of three
10745 things: a file system label, a file system UUID, or the name of a
10746 @file{/dev} node. Labels and UUIDs offer a way to refer to file
10747 systems without having to hard-code their actual device
10748 name@footnote{Note that, while it is tempting to use
10749 @file{/dev/disk/by-uuid} and similar device names to achieve the same
10750 result, this is not recommended: These special device nodes are created
10751 by the udev daemon and may be unavailable at the time the device is
10754 @findex file-system-label
10755 File system labels are created using the @code{file-system-label}
10756 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
10757 plain strings. Here's an example of a file system referred to by its
10758 label, as shown by the @command{e2label} command:
10762 (mount-point "/home")
10764 (device (file-system-label "my-home")))
10768 UUIDs are converted from their string representation (as shown by the
10769 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
10770 @code{uuid} form expects 16-byte UUIDs as defined in
10771 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
10772 form of UUID used by the ext2 family of file systems and others, but it
10773 is different from ``UUIDs'' found in FAT file systems, for instance.},
10778 (mount-point "/home")
10780 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
10783 When the source of a file system is a mapped device (@pxref{Mapped
10784 Devices}), its @code{device} field @emph{must} refer to the mapped
10785 device name---e.g., @file{"/dev/mapper/root-partition"}.
10786 This is required so that
10787 the system knows that mounting the file system depends on having the
10788 corresponding device mapping established.
10790 @item @code{flags} (default: @code{'()})
10791 This is a list of symbols denoting mount flags. Recognized flags
10792 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
10793 access to special files), @code{no-suid} (ignore setuid and setgid
10794 bits), @code{no-atime} (do not update file access times), and @code{no-exec}
10795 (disallow program execution). @xref{Mount-Unmount-Remount,,, libc, The GNU C
10796 Library Reference Manual}, for more information on these flags.
10798 @item @code{options} (default: @code{#f})
10799 This is either @code{#f}, or a string denoting mount options passed to the
10800 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
10801 Reference Manual}, for details and run @command{man 8 mount} for options for
10802 various file systems.
10804 @item @code{mount?} (default: @code{#t})
10805 This value indicates whether to automatically mount the file system when
10806 the system is brought up. When set to @code{#f}, the file system gets
10807 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
10808 is not automatically mounted.
10810 @item @code{needed-for-boot?} (default: @code{#f})
10811 This Boolean value indicates whether the file system is needed when
10812 booting. If that is true, then the file system is mounted when the
10813 initial RAM disk (initrd) is loaded. This is always the case, for
10814 instance, for the root file system.
10816 @item @code{check?} (default: @code{#t})
10817 This Boolean indicates whether the file system needs to be checked for
10818 errors before being mounted.
10820 @item @code{create-mount-point?} (default: @code{#f})
10821 When true, the mount point is created if it does not exist yet.
10823 @item @code{dependencies} (default: @code{'()})
10824 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
10825 representing file systems that must be mounted or mapped devices that
10826 must be opened before (and unmounted or closed after) this one.
10828 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
10829 a dependency of @file{/sys/fs/cgroup/cpu} and
10830 @file{/sys/fs/cgroup/memory}.
10832 Another example is a file system that depends on a mapped device, for
10833 example for an encrypted partition (@pxref{Mapped Devices}).
10837 The @code{(gnu system file-systems)} exports the following useful
10840 @defvr {Scheme Variable} %base-file-systems
10841 These are essential file systems that are required on normal systems,
10842 such as @var{%pseudo-terminal-file-system} and @var{%immutable-store} (see
10843 below.) Operating system declarations should always contain at least
10847 @defvr {Scheme Variable} %pseudo-terminal-file-system
10848 This is the file system to be mounted as @file{/dev/pts}. It supports
10849 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
10850 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
10851 Manual}). Pseudo-terminals are used by terminal emulators such as
10855 @defvr {Scheme Variable} %shared-memory-file-system
10856 This file system is mounted as @file{/dev/shm} and is used to support
10857 memory sharing across processes (@pxref{Memory-mapped I/O,
10858 @code{shm_open},, libc, The GNU C Library Reference Manual}).
10861 @defvr {Scheme Variable} %immutable-store
10862 This file system performs a read-only ``bind mount'' of
10863 @file{/gnu/store}, making it read-only for all the users including
10864 @code{root}. This prevents against accidental modification by software
10865 running as @code{root} or by system administrators.
10867 The daemon itself is still able to write to the store: it remounts it
10868 read-write in its own ``name space.''
10871 @defvr {Scheme Variable} %binary-format-file-system
10872 The @code{binfmt_misc} file system, which allows handling of arbitrary
10873 executable file types to be delegated to user space. This requires the
10874 @code{binfmt.ko} kernel module to be loaded.
10877 @defvr {Scheme Variable} %fuse-control-file-system
10878 The @code{fusectl} file system, which allows unprivileged users to mount
10879 and unmount user-space FUSE file systems. This requires the
10880 @code{fuse.ko} kernel module to be loaded.
10883 @node Mapped Devices
10884 @section Mapped Devices
10886 @cindex device mapping
10887 @cindex mapped devices
10888 The Linux kernel has a notion of @dfn{device mapping}: a block device,
10889 such as a hard disk partition, can be @dfn{mapped} into another device,
10890 usually in @code{/dev/mapper/},
10891 with additional processing over the data that flows through
10892 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
10893 concept of a ``mapped device'' and that of a file system: both boil down
10894 to @emph{translating} input/output operations made on a file to
10895 operations on its backing store. Thus, the Hurd implements mapped
10896 devices, like file systems, using the generic @dfn{translator} mechanism
10897 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
10898 typical example is encryption device mapping: all writes to the mapped
10899 device are encrypted, and all reads are deciphered, transparently.
10900 Guix extends this notion by considering any device or set of devices that
10901 are @dfn{transformed} in some way to create a new device; for instance,
10902 RAID devices are obtained by @dfn{assembling} several other devices, such
10903 as hard disks or partitions, into a new one that behaves as one partition.
10904 Other examples, not yet implemented, are LVM logical volumes.
10906 Mapped devices are declared using the @code{mapped-device} form,
10907 defined as follows; for examples, see below.
10909 @deftp {Data Type} mapped-device
10910 Objects of this type represent device mappings that will be made when
10911 the system boots up.
10915 This is either a string specifying the name of the block device to be mapped,
10916 such as @code{"/dev/sda3"}, or a list of such strings when several devices
10917 need to be assembled for creating a new one.
10920 This string specifies the name of the resulting mapped device. For
10921 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
10922 specifying @code{"my-partition"} leads to the creation of
10923 the @code{"/dev/mapper/my-partition"} device.
10924 For RAID devices of type @code{raid-device-mapping}, the full device name
10925 such as @code{"/dev/md0"} needs to be given.
10928 This must be a @code{mapped-device-kind} object, which specifies how
10929 @var{source} is mapped to @var{target}.
10933 @defvr {Scheme Variable} luks-device-mapping
10934 This defines LUKS block device encryption using the @command{cryptsetup}
10935 command from the package with the same name. It relies on the
10936 @code{dm-crypt} Linux kernel module.
10939 @defvr {Scheme Variable} raid-device-mapping
10940 This defines a RAID device, which is assembled using the @code{mdadm}
10941 command from the package with the same name. It requires a Linux kernel
10942 module for the appropriate RAID level to be loaded, such as @code{raid456}
10943 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
10946 @cindex disk encryption
10948 The following example specifies a mapping from @file{/dev/sda3} to
10949 @file{/dev/mapper/home} using LUKS---the
10950 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
10951 standard mechanism for disk encryption.
10952 The @file{/dev/mapper/home}
10953 device can then be used as the @code{device} of a @code{file-system}
10954 declaration (@pxref{File Systems}).
10958 (source "/dev/sda3")
10960 (type luks-device-mapping))
10963 Alternatively, to become independent of device numbering, one may obtain
10964 the LUKS UUID (@dfn{unique identifier}) of the source device by a
10968 cryptsetup luksUUID /dev/sda3
10971 and use it as follows:
10975 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
10977 (type luks-device-mapping))
10980 @cindex swap encryption
10981 It is also desirable to encrypt swap space, since swap space may contain
10982 sensitive data. One way to accomplish that is to use a swap file in a
10983 file system on a device mapped via LUKS encryption. In this way, the
10984 swap file is encrypted because the entire device is encrypted.
10985 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
10987 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
10988 may be declared as follows:
10992 (source (list "/dev/sda1" "/dev/sdb1"))
10993 (target "/dev/md0")
10994 (type raid-device-mapping))
10997 The @file{/dev/md0} device can then be used as the @code{device} of a
10998 @code{file-system} declaration (@pxref{File Systems}).
10999 Note that the RAID level need not be given; it is chosen during the
11000 initial creation and formatting of the RAID device and is determined
11001 automatically later.
11004 @node User Accounts
11005 @section User Accounts
11009 @cindex user accounts
11010 User accounts and groups are entirely managed through the
11011 @code{operating-system} declaration. They are specified with the
11012 @code{user-account} and @code{user-group} forms:
11018 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11019 "audio" ;sound card
11020 "video" ;video devices such as webcams
11021 "cdrom")) ;the good ol' CD-ROM
11022 (comment "Bob's sister")
11023 (home-directory "/home/alice"))
11026 When booting or upon completion of @command{guix system reconfigure},
11027 the system ensures that only the user accounts and groups specified in
11028 the @code{operating-system} declaration exist, and with the specified
11029 properties. Thus, account or group creations or modifications made by
11030 directly invoking commands such as @command{useradd} are lost upon
11031 reconfiguration or reboot. This ensures that the system remains exactly
11034 @deftp {Data Type} user-account
11035 Objects of this type represent user accounts. The following members may
11040 The name of the user account.
11044 This is the name (a string) or identifier (a number) of the user group
11045 this account belongs to.
11047 @item @code{supplementary-groups} (default: @code{'()})
11048 Optionally, this can be defined as a list of group names that this
11049 account belongs to.
11051 @item @code{uid} (default: @code{#f})
11052 This is the user ID for this account (a number), or @code{#f}. In the
11053 latter case, a number is automatically chosen by the system when the
11054 account is created.
11056 @item @code{comment} (default: @code{""})
11057 A comment about the account, such as the account owner's full name.
11059 @item @code{home-directory}
11060 This is the name of the home directory for the account.
11062 @item @code{create-home-directory?} (default: @code{#t})
11063 Indicates whether the home directory of this account should be created
11064 if it does not exist yet.
11066 @item @code{shell} (default: Bash)
11067 This is a G-expression denoting the file name of a program to be used as
11068 the shell (@pxref{G-Expressions}).
11070 @item @code{system?} (default: @code{#f})
11071 This Boolean value indicates whether the account is a ``system''
11072 account. System accounts are sometimes treated specially; for instance,
11073 graphical login managers do not list them.
11075 @anchor{user-account-password}
11076 @cindex password, for user accounts
11077 @item @code{password} (default: @code{#f})
11078 You would normally leave this field to @code{#f}, initialize user
11079 passwords as @code{root} with the @command{passwd} command, and then let
11080 users change it with @command{passwd}. Passwords set with
11081 @command{passwd} are of course preserved across reboot and
11084 If you @emph{do} want to set an initial password for an account, then
11085 this field must contain the encrypted password, as a string. You can use the
11086 @code{crypt} procedure for this purpose:
11093 ;; Specify a SHA-512-hashed initial password.
11094 (password (crypt "InitialPassword!" "$6$abc")))
11098 The hash of this initial password will be available in a file in
11099 @file{/gnu/store}, readable by all the users, so this method must be used with
11103 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11104 more information on password encryption, and @ref{Encryption,,, guile, GNU
11105 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11111 User group declarations are even simpler:
11114 (user-group (name "students"))
11117 @deftp {Data Type} user-group
11118 This type is for, well, user groups. There are just a few fields:
11122 The name of the group.
11124 @item @code{id} (default: @code{#f})
11125 The group identifier (a number). If @code{#f}, a new number is
11126 automatically allocated when the group is created.
11128 @item @code{system?} (default: @code{#f})
11129 This Boolean value indicates whether the group is a ``system'' group.
11130 System groups have low numerical IDs.
11132 @item @code{password} (default: @code{#f})
11133 What, user groups can have a password? Well, apparently yes. Unless
11134 @code{#f}, this field specifies the password of the group.
11139 For convenience, a variable lists all the basic user groups one may
11142 @defvr {Scheme Variable} %base-groups
11143 This is the list of basic user groups that users and/or packages expect
11144 to be present on the system. This includes groups such as ``root'',
11145 ``wheel'', and ``users'', as well as groups used to control access to
11146 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11149 @defvr {Scheme Variable} %base-user-accounts
11150 This is the list of basic system accounts that programs may expect to
11151 find on a GNU/Linux system, such as the ``nobody'' account.
11153 Note that the ``root'' account is not included here. It is a
11154 special-case and is automatically added whether or not it is specified.
11157 @node Keyboard Layout
11158 @section Keyboard Layout
11160 @cindex keyboard layout
11162 To specify what each key of your keyboard does, you need to tell the operating
11163 system what @dfn{keyboard layout} you want to use. The default, when nothing
11164 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11165 However, German speakers will usually prefer the German QWERTZ layout, French
11166 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11167 or bépo, and they might even want to further customize the effect of some of
11168 the keys. This section explains how to get that done.
11170 @cindex keyboard layout, definition
11171 There are three components that will want to know about your keyboard layout:
11175 The @emph{bootloader} may want to know what keyboard layout you want to use
11176 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11177 you want, for instance, to make sure that you can type the passphrase of your
11178 encrypted root partition using the right layout.
11181 The @emph{operating system kernel}, Linux, will need that so that the console
11182 is properly configured (@pxref{operating-system Reference,
11183 @code{keyboard-layout}}).
11186 The @emph{graphical display server}, usually Xorg, also has its own idea of
11187 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11190 Guix allows you to configure all three separately but, fortunately, it allows
11191 you to share the same keyboard layout for all three components.
11193 @cindex XKB, keyboard layouts
11194 Keyboard layouts are represented by records created by the
11195 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11196 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11197 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11198 optional variant name, an optional keyboard model name, and a possibly empty
11199 list of additional options. In most cases the layout name is all you care
11200 about. Here are a few example:
11203 ;; The German QWERTZ layout. Here we assume a standard
11204 ;; "pc105" keyboard model.
11205 (keyboard-layout "de")
11207 ;; The bépo variant of the French layout.
11208 (keyboard-layout "fr" "bepo")
11210 ;; The Catalan layout.
11211 (keyboard-layout "es" "cat")
11213 ;; The Latin American Spanish layout. In addition, the
11214 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11215 ;; and the "Menu" key is used as a "Compose" key to enter
11216 ;; accented letters.
11217 (keyboard-layout "latam"
11218 #:options '("ctrl:nocaps" "compose:menu"))
11220 ;; The Russian layout for a ThinkPad keyboard.
11221 (keyboard-layout "ru" #:model "thinkpad")
11223 ;; The "US international" layout, which is the US layout plus
11224 ;; dead keys to enter accented characters. This is for an
11225 ;; Apple MacBook keyboard.
11226 (keyboard-layout "us" "intl" #:model "macbook78")
11229 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11230 for a complete list of supported layouts, variants, and models.
11232 @cindex keyboard layout, configuration
11233 Let's say you want your system to use the Turkish keyboard layout throughout
11234 your system---bootloader, console, and Xorg. Here's what your system
11235 configuration would look like:
11237 @findex set-xorg-configuration
11239 ;; Using the Turkish layout for the bootloader, the console,
11244 (keyboard-layout (keyboard-layout "tr")) ;for the console
11245 (bootloader (bootloader-configuration
11246 (bootloader grub-efi-bootloader)
11247 (target "/boot/efi")
11248 (keyboard-layout keyboard-layout))) ;for GRUB
11249 (services (cons (set-xorg-configuration
11250 (xorg-configuration ;for Xorg
11251 (keyboard-layout keyboard-layout)))
11252 %desktop-services)))
11255 In the example above, for GRUB and for Xorg, we just refer to the
11256 @code{keyboard-layout} field defined above, but we could just as well refer to
11257 a different layout. The @code{set-xorg-configuration} procedure communicates
11258 the desired Xorg configuration to the graphical log-in manager, by default
11261 We've discussed how to specify the @emph{default} keyboard layout of your
11262 system when it starts, but you can also adjust it at run time:
11266 If you're using GNOME, its settings panel has a ``Region & Language'' entry
11267 where you can select one or more keyboard layouts.
11270 Under Xorg, the @command{setxkbmap} command (from the same-named package)
11271 allows you to change the current layout. For example, this is how you would
11272 change the layout to US Dvorak:
11275 setxkbmap us dvorak
11279 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
11280 console. However, note that @code{loadkeys} does @emph{not} use the XKB
11281 keyboard layout categorization described above. The command below loads the
11282 French bépo layout:
11293 A @dfn{locale} defines cultural conventions for a particular language
11294 and region of the world (@pxref{Locales,,, libc, The GNU C Library
11295 Reference Manual}). Each locale has a name that typically has the form
11296 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
11297 @code{fr_LU.utf8} designates the locale for the French language, with
11298 cultural conventions from Luxembourg, and using the UTF-8 encoding.
11300 @cindex locale definition
11301 Usually, you will want to specify the default locale for the machine
11302 using the @code{locale} field of the @code{operating-system} declaration
11303 (@pxref{operating-system Reference, @code{locale}}).
11305 The selected locale is automatically added to the @dfn{locale
11306 definitions} known to the system if needed, with its codeset inferred
11307 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
11308 @code{UTF-8} codeset. Additional locale definitions can be specified in
11309 the @code{locale-definitions} slot of @code{operating-system}---this is
11310 useful, for instance, if the codeset could not be inferred from the
11311 locale name. The default set of locale definitions includes some widely
11312 used locales, but not all the available locales, in order to save space.
11314 For instance, to add the North Frisian locale for Germany, the value of
11318 (cons (locale-definition
11319 (name "fy_DE.utf8") (source "fy_DE"))
11320 %default-locale-definitions)
11323 Likewise, to save space, one might want @code{locale-definitions} to
11324 list only the locales that are actually used, as in:
11327 (list (locale-definition
11328 (name "ja_JP.eucjp") (source "ja_JP")
11329 (charset "EUC-JP")))
11333 The compiled locale definitions are available at
11334 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
11335 version, which is the default location where the GNU@tie{}libc provided
11336 by Guix looks for locale data. This can be overridden using the
11337 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
11338 @code{LOCPATH} and locale packages}).
11340 The @code{locale-definition} form is provided by the @code{(gnu system
11341 locale)} module. Details are given below.
11343 @deftp {Data Type} locale-definition
11344 This is the data type of a locale definition.
11349 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
11350 Reference Manual}, for more information on locale names.
11352 @item @code{source}
11353 The name of the source for that locale. This is typically the
11354 @code{@var{language}_@var{territory}} part of the locale name.
11356 @item @code{charset} (default: @code{"UTF-8"})
11357 The ``character set'' or ``code set'' for that locale,
11358 @uref{https://www.iana.org/assignments/character-sets, as defined by
11364 @defvr {Scheme Variable} %default-locale-definitions
11365 A list of commonly used UTF-8 locales, used as the default
11366 value of the @code{locale-definitions} field of @code{operating-system}
11369 @cindex locale name
11370 @cindex normalized codeset in locale names
11371 These locale definitions use the @dfn{normalized codeset} for the part
11372 that follows the dot in the name (@pxref{Using gettextized software,
11373 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
11374 instance it has @code{uk_UA.utf8} but @emph{not}, say,
11375 @code{uk_UA.UTF-8}.
11378 @subsection Locale Data Compatibility Considerations
11380 @cindex incompatibility, of locale data
11381 @code{operating-system} declarations provide a @code{locale-libcs} field
11382 to specify the GNU@tie{}libc packages that are used to compile locale
11383 declarations (@pxref{operating-system Reference}). ``Why would I
11384 care?'', you may ask. Well, it turns out that the binary format of
11385 locale data is occasionally incompatible from one libc version to
11388 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
11389 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
11390 For instance, a program linked against libc version 2.21 is unable to
11391 read locale data produced with libc 2.22; worse, that program
11392 @emph{aborts} instead of simply ignoring the incompatible locale
11393 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
11394 the incompatible locale data, which is already an improvement.}.
11395 Similarly, a program linked against libc 2.22 can read most, but not
11396 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
11397 data is incompatible); thus calls to @code{setlocale} may fail, but
11398 programs will not abort.
11400 The ``problem'' with Guix is that users have a lot of freedom: They can
11401 choose whether and when to upgrade software in their profiles, and might
11402 be using a libc version different from the one the system administrator
11403 used to build the system-wide locale data.
11405 Fortunately, unprivileged users can also install their own locale data
11406 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
11407 @code{GUIX_LOCPATH} and locale packages}).
11409 Still, it is best if the system-wide locale data at
11410 @file{/run/current-system/locale} is built for all the libc versions
11411 actually in use on the system, so that all the programs can access
11412 it---this is especially crucial on a multi-user system. To do that, the
11413 administrator can specify several libc packages in the
11414 @code{locale-libcs} field of @code{operating-system}:
11417 (use-package-modules base)
11421 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
11424 This example would lead to a system containing locale definitions for
11425 both libc 2.21 and the current version of libc in
11426 @file{/run/current-system/locale}.
11432 @cindex system services
11433 An important part of preparing an @code{operating-system} declaration is
11434 listing @dfn{system services} and their configuration (@pxref{Using the
11435 Configuration System}). System services are typically daemons launched
11436 when the system boots, or other actions needed at that time---e.g.,
11437 configuring network access.
11439 Guix has a broad definition of ``service'' (@pxref{Service
11440 Composition}), but many services are managed by the GNU@tie{}Shepherd
11441 (@pxref{Shepherd Services}). On a running system, the @command{herd}
11442 command allows you to list the available services, show their status,
11443 start and stop them, or do other specific operations (@pxref{Jump
11444 Start,,, shepherd, The GNU Shepherd Manual}). For example:
11450 The above command, run as @code{root}, lists the currently defined
11451 services. The @command{herd doc} command shows a synopsis of the given
11452 service and its associated actions:
11456 Run libc's name service cache daemon (nscd).
11458 # herd doc nscd action invalidate
11459 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
11462 The @command{start}, @command{stop}, and @command{restart} sub-commands
11463 have the effect you would expect. For instance, the commands below stop
11464 the nscd service and restart the Xorg display server:
11468 Service nscd has been stopped.
11469 # herd restart xorg-server
11470 Service xorg-server has been stopped.
11471 Service xorg-server has been started.
11474 The following sections document the available services, starting with
11475 the core services, that may be used in an @code{operating-system}
11479 * Base Services:: Essential system services.
11480 * Scheduled Job Execution:: The mcron service.
11481 * Log Rotation:: The rottlog service.
11482 * Networking Services:: Network setup, SSH daemon, etc.
11483 * X Window:: Graphical display.
11484 * Printing Services:: Local and remote printer support.
11485 * Desktop Services:: D-Bus and desktop services.
11486 * Sound Services:: ALSA and Pulseaudio services.
11487 * Database Services:: SQL databases, key-value stores, etc.
11488 * Mail Services:: IMAP, POP3, SMTP, and all that.
11489 * Messaging Services:: Messaging services.
11490 * Telephony Services:: Telephony services.
11491 * Monitoring Services:: Monitoring services.
11492 * Kerberos Services:: Kerberos services.
11493 * LDAP Services:: LDAP services.
11494 * Web Services:: Web servers.
11495 * Certificate Services:: TLS certificates via Let's Encrypt.
11496 * DNS Services:: DNS daemons.
11497 * VPN Services:: VPN daemons.
11498 * Network File System:: NFS related services.
11499 * Continuous Integration:: The Cuirass service.
11500 * Power Management Services:: Extending battery life.
11501 * Audio Services:: The MPD.
11502 * Virtualization Services:: Virtualization services.
11503 * Version Control Services:: Providing remote access to Git repositories.
11504 * Game Services:: Game servers.
11505 * Miscellaneous Services:: Other services.
11508 @node Base Services
11509 @subsection Base Services
11511 The @code{(gnu services base)} module provides definitions for the basic
11512 services that one expects from the system. The services exported by
11513 this module are listed below.
11515 @defvr {Scheme Variable} %base-services
11516 This variable contains a list of basic services (@pxref{Service Types
11517 and Services}, for more information on service objects) one would
11518 expect from the system: a login service (mingetty) on each tty, syslogd,
11519 the libc name service cache daemon (nscd), the udev device manager, and
11522 This is the default value of the @code{services} field of
11523 @code{operating-system} declarations. Usually, when customizing a
11524 system, you will want to append services to @var{%base-services}, like
11528 (append (list (service avahi-service-type)
11529 (service openssh-service-type))
11534 @defvr {Scheme Variable} special-files-service-type
11535 This is the service that sets up ``special files'' such as
11536 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
11538 The value associated with @code{special-files-service-type} services
11539 must be a list of tuples where the first element is the ``special file''
11540 and the second element is its target. By default it is:
11542 @cindex @file{/bin/sh}
11543 @cindex @file{sh}, in @file{/bin}
11545 `(("/bin/sh" ,(file-append @var{bash} "/bin/sh")))
11548 @cindex @file{/usr/bin/env}
11549 @cindex @file{env}, in @file{/usr/bin}
11550 If you want to add, say, @code{/usr/bin/env} to your system, you can
11554 `(("/bin/sh" ,(file-append @var{bash} "/bin/sh"))
11555 ("/usr/bin/env" ,(file-append @var{coreutils} "/bin/env")))
11558 Since this is part of @code{%base-services}, you can use
11559 @code{modify-services} to customize the set of special files
11560 (@pxref{Service Reference, @code{modify-services}}). But the simple way
11561 to add a special file is @i{via} the @code{extra-special-file} procedure
11565 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
11566 Use @var{target} as the ``special file'' @var{file}.
11568 For example, adding the following lines to the @code{services} field of
11569 your operating system declaration leads to a @file{/usr/bin/env}
11573 (extra-special-file "/usr/bin/env"
11574 (file-append coreutils "/bin/env"))
11578 @deffn {Scheme Procedure} host-name-service @var{name}
11579 Return a service that sets the host name to @var{name}.
11582 @deffn {Scheme Procedure} login-service @var{config}
11583 Return a service to run login according to @var{config}, a
11584 @code{<login-configuration>} object, which specifies the message of the day,
11585 among other things.
11588 @deftp {Data Type} login-configuration
11589 This is the data type representing the configuration of login.
11594 @cindex message of the day
11595 A file-like object containing the ``message of the day''.
11597 @item @code{allow-empty-passwords?} (default: @code{#t})
11598 Allow empty passwords by default so that first-time users can log in when
11599 the 'root' account has just been created.
11604 @deffn {Scheme Procedure} mingetty-service @var{config}
11605 Return a service to run mingetty according to @var{config}, a
11606 @code{<mingetty-configuration>} object, which specifies the tty to run, among
11610 @deftp {Data Type} mingetty-configuration
11611 This is the data type representing the configuration of Mingetty, which
11612 provides the default implementation of virtual console log-in.
11617 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
11619 @item @code{auto-login} (default: @code{#f})
11620 When true, this field must be a string denoting the user name under
11621 which the system automatically logs in. When it is @code{#f}, a
11622 user name and password must be entered to log in.
11624 @item @code{login-program} (default: @code{#f})
11625 This must be either @code{#f}, in which case the default log-in program
11626 is used (@command{login} from the Shadow tool suite), or a gexp denoting
11627 the name of the log-in program.
11629 @item @code{login-pause?} (default: @code{#f})
11630 When set to @code{#t} in conjunction with @var{auto-login}, the user
11631 will have to press a key before the log-in shell is launched.
11633 @item @code{mingetty} (default: @var{mingetty})
11634 The Mingetty package to use.
11639 @deffn {Scheme Procedure} agetty-service @var{config}
11640 Return a service to run agetty according to @var{config}, an
11641 @code{<agetty-configuration>} object, which specifies the tty to run,
11642 among other things.
11645 @deftp {Data Type} agetty-configuration
11646 This is the data type representing the configuration of agetty, which
11647 implements virtual and serial console log-in. See the @code{agetty(8)}
11648 man page for more information.
11653 The name of the console this agetty runs on, as a string---e.g.,
11654 @code{"ttyS0"}. This argument is optional, it will default to
11655 a reasonable default serial port used by the kernel Linux.
11657 For this, if there is a value for an option @code{agetty.tty} in the kernel
11658 command line, agetty will extract the device name of the serial port
11659 from it and use that.
11661 If not and if there is a value for an option @code{console} with a tty in
11662 the Linux command line, agetty will extract the device name of the
11663 serial port from it and use that.
11665 In both cases, agetty will leave the other serial device settings
11666 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
11669 @item @code{baud-rate} (default: @code{#f})
11670 A string containing a comma-separated list of one or more baud rates, in
11673 @item @code{term} (default: @code{#f})
11674 A string containing the value used for the @code{TERM} environment
11677 @item @code{eight-bits?} (default: @code{#f})
11678 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
11681 @item @code{auto-login} (default: @code{#f})
11682 When passed a login name, as a string, the specified user will be logged
11683 in automatically without prompting for their login name or password.
11685 @item @code{no-reset?} (default: @code{#f})
11686 When @code{#t}, don't reset terminal cflags (control modes).
11688 @item @code{host} (default: @code{#f})
11689 This accepts a string containing the "login_host", which will be written
11690 into the @file{/var/run/utmpx} file.
11692 @item @code{remote?} (default: @code{#f})
11693 When set to @code{#t} in conjunction with @var{host}, this will add an
11694 @code{-r} fakehost option to the command line of the login program
11695 specified in @var{login-program}.
11697 @item @code{flow-control?} (default: @code{#f})
11698 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
11700 @item @code{no-issue?} (default: @code{#f})
11701 When set to @code{#t}, the contents of the @file{/etc/issue} file will
11702 not be displayed before presenting the login prompt.
11704 @item @code{init-string} (default: @code{#f})
11705 This accepts a string that will be sent to the tty or modem before
11706 sending anything else. It can be used to initialize a modem.
11708 @item @code{no-clear?} (default: @code{#f})
11709 When set to @code{#t}, agetty will not clear the screen before showing
11712 @item @code{login-program} (default: (file-append shadow "/bin/login"))
11713 This must be either a gexp denoting the name of a log-in program, or
11714 unset, in which case the default value is the @command{login} from the
11717 @item @code{local-line} (default: @code{#f})
11718 Control the CLOCAL line flag. This accepts one of three symbols as
11719 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
11720 the default value chosen by agetty is @code{'auto}.
11722 @item @code{extract-baud?} (default: @code{#f})
11723 When set to @code{#t}, instruct agetty to try to extract the baud rate
11724 from the status messages produced by certain types of modems.
11726 @item @code{skip-login?} (default: @code{#f})
11727 When set to @code{#t}, do not prompt the user for a login name. This
11728 can be used with @var{login-program} field to use non-standard login
11731 @item @code{no-newline?} (default: @code{#f})
11732 When set to @code{#t}, do not print a newline before printing the
11733 @file{/etc/issue} file.
11735 @c Is this dangerous only when used with login-program, or always?
11736 @item @code{login-options} (default: @code{#f})
11737 This option accepts a string containing options that are passed to the
11738 login program. When used with the @var{login-program}, be aware that a
11739 malicious user could try to enter a login name containing embedded
11740 options that could be parsed by the login program.
11742 @item @code{login-pause} (default: @code{#f})
11743 When set to @code{#t}, wait for any key before showing the login prompt.
11744 This can be used in conjunction with @var{auto-login} to save memory by
11745 lazily spawning shells.
11747 @item @code{chroot} (default: @code{#f})
11748 Change root to the specified directory. This option accepts a directory
11751 @item @code{hangup?} (default: @code{#f})
11752 Use the Linux system call @code{vhangup} to do a virtual hangup of the
11753 specified terminal.
11755 @item @code{keep-baud?} (default: @code{#f})
11756 When set to @code{#t}, try to keep the existing baud rate. The baud
11757 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
11760 @item @code{timeout} (default: @code{#f})
11761 When set to an integer value, terminate if no user name could be read
11762 within @var{timeout} seconds.
11764 @item @code{detect-case?} (default: @code{#f})
11765 When set to @code{#t}, turn on support for detecting an uppercase-only
11766 terminal. This setting will detect a login name containing only
11767 uppercase letters as indicating an uppercase-only terminal and turn on
11768 some upper-to-lower case conversions. Note that this will not support
11769 Unicode characters.
11771 @item @code{wait-cr?} (default: @code{#f})
11772 When set to @code{#t}, wait for the user or modem to send a
11773 carriage-return or linefeed character before displaying
11774 @file{/etc/issue} or login prompt. This is typically used with the
11775 @var{init-string} option.
11777 @item @code{no-hints?} (default: @code{#f})
11778 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
11781 @item @code{no-hostname?} (default: @code{#f})
11782 By default, the hostname is printed. When this option is set to
11783 @code{#t}, no hostname will be shown at all.
11785 @item @code{long-hostname?} (default: @code{#f})
11786 By default, the hostname is only printed until the first dot. When this
11787 option is set to @code{#t}, the fully qualified hostname by
11788 @code{gethostname} or @code{getaddrinfo} is shown.
11790 @item @code{erase-characters} (default: @code{#f})
11791 This option accepts a string of additional characters that should be
11792 interpreted as backspace when the user types their login name.
11794 @item @code{kill-characters} (default: @code{#f})
11795 This option accepts a string that should be interpreted to mean "ignore
11796 all previous characters" (also called a "kill" character) when the user
11797 types their login name.
11799 @item @code{chdir} (default: @code{#f})
11800 This option accepts, as a string, a directory path that will be changed
11803 @item @code{delay} (default: @code{#f})
11804 This options accepts, as an integer, the number of seconds to sleep
11805 before opening the tty and displaying the login prompt.
11807 @item @code{nice} (default: @code{#f})
11808 This option accepts, as an integer, the nice value with which to run the
11809 @command{login} program.
11811 @item @code{extra-options} (default: @code{'()})
11812 This option provides an "escape hatch" for the user to provide arbitrary
11813 command-line arguments to @command{agetty} as a list of strings.
11818 @deffn {Scheme Procedure} kmscon-service-type @var{config}
11819 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
11820 according to @var{config}, a @code{<kmscon-configuration>} object, which
11821 specifies the tty to run, among other things.
11824 @deftp {Data Type} kmscon-configuration
11825 This is the data type representing the configuration of Kmscon, which
11826 implements virtual console log-in.
11830 @item @code{virtual-terminal}
11831 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
11833 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
11834 A gexp denoting the name of the log-in program. The default log-in program is
11835 @command{login} from the Shadow tool suite.
11837 @item @code{login-arguments} (default: @code{'("-p")})
11838 A list of arguments to pass to @command{login}.
11840 @item @code{auto-login} (default: @code{#f})
11841 When passed a login name, as a string, the specified user will be logged
11842 in automatically without prompting for their login name or password.
11844 @item @code{hardware-acceleration?} (default: #f)
11845 Whether to use hardware acceleration.
11847 @item @code{kmscon} (default: @var{kmscon})
11848 The Kmscon package to use.
11853 @cindex name service cache daemon
11855 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
11856 [#:name-services '()]
11857 Return a service that runs the libc name service cache daemon (nscd) with the
11858 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
11859 Service Switch}, for an example.
11861 For convenience, the Shepherd service for nscd provides the following actions:
11865 @cindex cache invalidation, nscd
11866 @cindex nscd, cache invalidation
11867 This invalidate the given cache. For instance, running:
11870 herd invalidate nscd hosts
11874 invalidates the host name lookup cache of nscd.
11877 Running @command{herd statistics nscd} displays information about nscd usage
11883 @defvr {Scheme Variable} %nscd-default-configuration
11884 This is the default @code{<nscd-configuration>} value (see below) used
11885 by @code{nscd-service}. It uses the caches defined by
11886 @var{%nscd-default-caches}; see below.
11889 @deftp {Data Type} nscd-configuration
11890 This is the data type representing the name service cache daemon (nscd)
11895 @item @code{name-services} (default: @code{'()})
11896 List of packages denoting @dfn{name services} that must be visible to
11897 the nscd---e.g., @code{(list @var{nss-mdns})}.
11899 @item @code{glibc} (default: @var{glibc})
11900 Package object denoting the GNU C Library providing the @command{nscd}
11903 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
11904 Name of the nscd log file. This is where debugging output goes when
11905 @code{debug-level} is strictly positive.
11907 @item @code{debug-level} (default: @code{0})
11908 Integer denoting the debugging levels. Higher numbers mean that more
11909 debugging output is logged.
11911 @item @code{caches} (default: @var{%nscd-default-caches})
11912 List of @code{<nscd-cache>} objects denoting things to be cached; see
11918 @deftp {Data Type} nscd-cache
11919 Data type representing a cache database of nscd and its parameters.
11923 @item @code{database}
11924 This is a symbol representing the name of the database to be cached.
11925 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
11926 @code{services}, which designate the corresponding NSS database
11927 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
11929 @item @code{positive-time-to-live}
11930 @itemx @code{negative-time-to-live} (default: @code{20})
11931 A number representing the number of seconds during which a positive or
11932 negative lookup result remains in cache.
11934 @item @code{check-files?} (default: @code{#t})
11935 Whether to check for updates of the files corresponding to
11938 For instance, when @var{database} is @code{hosts}, setting this flag
11939 instructs nscd to check for updates in @file{/etc/hosts} and to take
11942 @item @code{persistent?} (default: @code{#t})
11943 Whether the cache should be stored persistently on disk.
11945 @item @code{shared?} (default: @code{#t})
11946 Whether the cache should be shared among users.
11948 @item @code{max-database-size} (default: 32@tie{}MiB)
11949 Maximum size in bytes of the database cache.
11951 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
11952 @c settings, so leave them out.
11957 @defvr {Scheme Variable} %nscd-default-caches
11958 List of @code{<nscd-cache>} objects used by default by
11959 @code{nscd-configuration} (see above).
11961 It enables persistent and aggressive caching of service and host name
11962 lookups. The latter provides better host name lookup performance,
11963 resilience in the face of unreliable name servers, and also better
11964 privacy---often the result of host name lookups is in local cache, so
11965 external name servers do not even need to be queried.
11968 @anchor{syslog-configuration-type}
11971 @deftp {Data Type} syslog-configuration
11972 This data type represents the configuration of the syslog daemon.
11975 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
11976 The syslog daemon to use.
11978 @item @code{config-file} (default: @code{%default-syslog.conf})
11979 The syslog configuration file to use.
11984 @anchor{syslog-service}
11986 @deffn {Scheme Procedure} syslog-service @var{config}
11987 Return a service that runs a syslog daemon according to @var{config}.
11989 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
11990 information on the configuration file syntax.
11993 @defvr {Scheme Variable} guix-service-type
11994 This is the type of the service that runs the build daemon,
11995 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
11996 @code{guix-configuration} record as described below.
11999 @anchor{guix-configuration-type}
12000 @deftp {Data Type} guix-configuration
12001 This data type represents the configuration of the Guix build daemon.
12002 @xref{Invoking guix-daemon}, for more information.
12005 @item @code{guix} (default: @var{guix})
12006 The Guix package to use.
12008 @item @code{build-group} (default: @code{"guixbuild"})
12009 Name of the group for build user accounts.
12011 @item @code{build-accounts} (default: @code{10})
12012 Number of build user accounts to create.
12014 @item @code{authorize-key?} (default: @code{#t})
12015 @cindex substitutes, authorization thereof
12016 Whether to authorize the substitute keys listed in
12017 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12018 (@pxref{Substitutes}).
12020 @vindex %default-authorized-guix-keys
12021 @item @code{authorized-keys} (default: @var{%default-authorized-guix-keys})
12022 The list of authorized key files for archive imports, as a list of
12023 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12024 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12026 @item @code{use-substitutes?} (default: @code{#t})
12027 Whether to use substitutes.
12029 @item @code{substitute-urls} (default: @var{%default-substitute-urls})
12030 The list of URLs where to look for substitutes by default.
12032 @item @code{max-silent-time} (default: @code{0})
12033 @itemx @code{timeout} (default: @code{0})
12034 The number of seconds of silence and the number of seconds of activity,
12035 respectively, after which a build process times out. A value of zero
12036 disables the timeout.
12038 @item @code{log-compression} (default: @code{'bzip2})
12039 The type of compression used for build logs---one of @code{gzip},
12040 @code{bzip2}, or @code{none}.
12042 @item @code{extra-options} (default: @code{'()})
12043 List of extra command-line options for @command{guix-daemon}.
12045 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12046 File where @command{guix-daemon}'s standard output and standard error
12049 @item @code{http-proxy} (default: @code{#f})
12050 The HTTP proxy used for downloading fixed-output derivations and
12053 @item @code{tmpdir} (default: @code{#f})
12054 A directory path where the @command{guix-daemon} will perform builds.
12059 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12060 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12061 udev rules can be provided as a list of files through the @var{rules}
12062 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12063 @code{(gnu services base)} simplify the creation of such rule files.
12066 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12067 Return a udev-rule file named @var{file-name} containing the rules
12068 defined by the @var{contents} literal.
12070 In the following example, a rule for a USB device is defined to be
12071 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12072 upon detecting a USB device with a given product identifier.
12075 (define %example-udev-rule
12077 "90-usb-thing.rules"
12078 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12079 "ATTR@{product@}==\"Example\", "
12080 "RUN+=\"/path/to/script\"")))
12083 The @command{herd rules udev} command, as root, returns the name of the
12084 directory containing all the active udev rules.
12087 Here we show how the default @var{udev-service} can be extended with it.
12093 (modify-services %desktop-services
12094 (udev-service-type config =>
12095 (udev-configuration (inherit config)
12096 (rules (append (udev-configuration-rules config)
12097 (list %example-udev-rule))))))))
12100 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12101 Return a udev file named @var{file-name} containing the rules defined
12102 within @var{file}, a file-like object.
12104 The following example showcases how we can use an existing rule file.
12107 (use-modules (guix download) ;for url-fetch
12108 (guix packages) ;for origin
12111 (define %android-udev-rules
12113 "51-android-udev.rules"
12114 (let ((version "20170910"))
12117 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12118 "android-udev-rules/" version "/51-android.rules"))
12120 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12124 Additionally, Guix package definitions can be included in @var{rules} in
12125 order to extend the udev rules with the definitions found under their
12126 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12127 @var{file->udev-rule} example, we could have used the
12128 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12129 packages android)} module.
12131 The following example shows how to use the @var{android-udev-rules}
12132 package so that the Android tool @command{adb} can detect devices
12133 without root privileges. It also details how to create the
12134 @code{adbusers} group, which is required for the proper functioning of
12135 the rules defined within the @var{android-udev-rules} package. To
12136 create such a group, we must define it both as part of the
12137 @var{supplementary-groups} of our @var{user-account} declaration, as
12138 well as in the @var{groups} field of the @var{operating-system} record.
12141 (use-modules (gnu packages android) ;for android-udev-rules
12142 (gnu system shadow) ;for user-group
12147 (users (cons (user-acount
12149 (supplementary-groups
12150 '("adbusers" ;for adb
12151 "wheel" "netdev" "audio" "video"))
12154 (groups (cons (user-group (system? #t) (name "adbusers"))
12160 (modify-services %desktop-services
12163 (udev-configuration (inherit config)
12164 (rules (cons android-udev-rules
12165 (udev-configuration-rules config))))))))
12168 @defvr {Scheme Variable} urandom-seed-service-type
12169 Save some entropy in @var{%random-seed-file} to seed @file{/dev/urandom}
12170 when rebooting. It also tries to seed @file{/dev/urandom} from
12171 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12175 @defvr {Scheme Variable} %random-seed-file
12176 This is the name of the file where some random bytes are saved by
12177 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12178 It defaults to @file{/var/lib/random-seed}.
12183 @defvr {Scheme Variable} gpm-service-type
12184 This is the type of the service that runs GPM, the @dfn{general-purpose
12185 mouse daemon}, which provides mouse support to the Linux console. GPM
12186 allows users to use the mouse in the console, notably to select, copy,
12189 The value for services of this type must be a @code{gpm-configuration}
12190 (see below). This service is not part of @var{%base-services}.
12193 @deftp {Data Type} gpm-configuration
12194 Data type representing the configuration of GPM.
12197 @item @code{options} (default: @code{%default-gpm-options})
12198 Command-line options passed to @command{gpm}. The default set of
12199 options instruct @command{gpm} to listen to mouse events on
12200 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12203 @item @code{gpm} (default: @code{gpm})
12204 The GPM package to use.
12209 @anchor{guix-publish-service-type}
12210 @deffn {Scheme Variable} guix-publish-service-type
12211 This is the service type for @command{guix publish} (@pxref{Invoking
12212 guix publish}). Its value must be a @code{guix-configuration}
12213 object, as described below.
12215 This assumes that @file{/etc/guix} already contains a signing key pair as
12216 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12217 archive}). If that is not the case, the service will fail to start.
12220 @deftp {Data Type} guix-publish-configuration
12221 Data type representing the configuration of the @code{guix publish}
12225 @item @code{guix} (default: @code{guix})
12226 The Guix package to use.
12228 @item @code{port} (default: @code{80})
12229 The TCP port to listen for connections.
12231 @item @code{host} (default: @code{"localhost"})
12232 The host (and thus, network interface) to listen to. Use
12233 @code{"0.0.0.0"} to listen on all the network interfaces.
12235 @item @code{compression-level} (default: @code{3})
12236 The gzip compression level at which substitutes are compressed. Use
12237 @code{0} to disable compression altogether, and @code{9} to get the best
12238 compression ratio at the expense of increased CPU usage.
12240 @item @code{nar-path} (default: @code{"nar"})
12241 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
12242 publish, @code{--nar-path}}, for details.
12244 @item @code{cache} (default: @code{#f})
12245 When it is @code{#f}, disable caching and instead generate archives on
12246 demand. Otherwise, this should be the name of a directory---e.g.,
12247 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
12248 archives and meta-data ready to be sent. @xref{Invoking guix publish,
12249 @option{--cache}}, for more information on the tradeoffs involved.
12251 @item @code{workers} (default: @code{#f})
12252 When it is an integer, this is the number of worker threads used for
12253 caching; when @code{#f}, the number of processors is used.
12254 @xref{Invoking guix publish, @option{--workers}}, for more information.
12256 @item @code{ttl} (default: @code{#f})
12257 When it is an integer, this denotes the @dfn{time-to-live} in seconds
12258 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
12259 for more information.
12263 @anchor{rngd-service}
12264 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
12265 [#:device "/dev/hwrng"]
12266 Return a service that runs the @command{rngd} program from @var{rng-tools}
12267 to add @var{device} to the kernel's entropy pool. The service will fail if
12268 @var{device} does not exist.
12271 @anchor{pam-limits-service}
12272 @cindex session limits
12277 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
12279 Return a service that installs a configuration file for the
12280 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
12281 @code{pam_limits} module}. The procedure optionally takes a list of
12282 @code{pam-limits-entry} values, which can be used to specify
12283 @code{ulimit} limits and nice priority limits to user sessions.
12285 The following limits definition sets two hard and soft limits for all
12286 login sessions of users in the @code{realtime} group:
12289 (pam-limits-service
12291 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
12292 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
12295 The first entry increases the maximum realtime priority for
12296 non-privileged processes; the second entry lifts any restriction of the
12297 maximum address space that can be locked in memory. These settings are
12298 commonly used for real-time audio systems.
12301 @node Scheduled Job Execution
12302 @subsection Scheduled Job Execution
12306 @cindex scheduling jobs
12307 The @code{(gnu services mcron)} module provides an interface to
12308 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
12309 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
12310 Unix @command{cron} daemon; the main difference is that it is
12311 implemented in Guile Scheme, which provides a lot of flexibility when
12312 specifying the scheduling of jobs and their actions.
12314 The example below defines an operating system that runs the
12315 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
12316 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
12317 well as the @command{mkid} command on behalf of an unprivileged user
12318 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
12319 gexps to introduce job definitions that are passed to mcron
12320 (@pxref{G-Expressions}).
12323 (use-modules (guix) (gnu) (gnu services mcron))
12324 (use-package-modules base idutils)
12326 (define updatedb-job
12327 ;; Run 'updatedb' at 3AM every day. Here we write the
12328 ;; job's action as a Scheme procedure.
12329 #~(job '(next-hour '(3))
12331 (execl (string-append #$findutils "/bin/updatedb")
12333 "--prunepaths=/tmp /var/tmp /gnu/store"))))
12335 (define garbage-collector-job
12336 ;; Collect garbage 5 minutes after midnight every day.
12337 ;; The job's action is a shell command.
12338 #~(job "5 0 * * *" ;Vixie cron syntax
12341 (define idutils-job
12342 ;; Update the index database as user "charlie" at 12:15PM
12343 ;; and 19:15PM. This runs from the user's home directory.
12344 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
12345 (string-append #$idutils "/bin/mkid src")
12350 (services (cons (service mcron-service-type
12351 (mcron-configuration
12352 (jobs (list garbage-collector-job
12358 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
12359 for more information on mcron job specifications. Below is the
12360 reference of the mcron service.
12362 On a running system, you can use the @code{schedule} action of the service to
12363 visualize the mcron jobs that will be executed next:
12366 # herd schedule mcron
12370 The example above lists the next five tasks that will be executed, but you can
12371 also specify the number of tasks to display:
12374 # herd schedule mcron 10
12377 @defvr {Scheme Variable} mcron-service-type
12378 This is the type of the @code{mcron} service, whose value is an
12379 @code{mcron-configuration} object.
12381 This service type can be the target of a service extension that provides
12382 it additional job specifications (@pxref{Service Composition}). In
12383 other words, it is possible to define services that provide additional
12387 @deftp {Data Type} mcron-configuration
12388 Data type representing the configuration of mcron.
12391 @item @code{mcron} (default: @var{mcron})
12392 The mcron package to use.
12395 This is a list of gexps (@pxref{G-Expressions}), where each gexp
12396 corresponds to an mcron job specification (@pxref{Syntax, mcron job
12397 specifications,, mcron, GNU@tie{}mcron}).
12403 @subsection Log Rotation
12406 @cindex log rotation
12408 Log files such as those found in @file{/var/log} tend to grow endlessly,
12409 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
12410 their contents in separate files, possibly compressed. The @code{(gnu
12411 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
12412 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
12414 The example below defines an operating system that provides log rotation
12415 with the default settings, for commonly encountered log files.
12418 (use-modules (guix) (gnu))
12419 (use-service-modules admin mcron)
12420 (use-package-modules base idutils)
12424 (services (cons (service rottlog-service-type)
12428 @defvr {Scheme Variable} rottlog-service-type
12429 This is the type of the Rottlog service, whose value is a
12430 @code{rottlog-configuration} object.
12432 Other services can extend this one with new @code{log-rotation} objects
12433 (see below), thereby augmenting the set of files to be rotated.
12435 This service type can define mcron jobs (@pxref{Scheduled Job
12436 Execution}) to run the rottlog service.
12439 @deftp {Data Type} rottlog-configuration
12440 Data type representing the configuration of rottlog.
12443 @item @code{rottlog} (default: @code{rottlog})
12444 The Rottlog package to use.
12446 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
12447 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
12448 rottlog, GNU Rot[t]log Manual}).
12450 @item @code{rotations} (default: @code{%default-rotations})
12451 A list of @code{log-rotation} objects as defined below.
12454 This is a list of gexps where each gexp corresponds to an mcron job
12455 specification (@pxref{Scheduled Job Execution}).
12459 @deftp {Data Type} log-rotation
12460 Data type representing the rotation of a group of log files.
12462 Taking an example from the Rottlog manual (@pxref{Period Related File
12463 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
12469 (files '("/var/log/apache/*"))
12470 (options '("storedir apache-archives"
12476 The list of fields is as follows:
12479 @item @code{frequency} (default: @code{'weekly})
12480 The log rotation frequency, a symbol.
12483 The list of files or file glob patterns to rotate.
12485 @item @code{options} (default: @code{'()})
12486 The list of rottlog options for this rotation (@pxref{Configuration
12487 parameters,,, rottlog, GNU Rot[t]lg Manual}).
12489 @item @code{post-rotate} (default: @code{#f})
12490 Either @code{#f} or a gexp to execute once the rotation has completed.
12494 @defvr {Scheme Variable} %default-rotations
12495 Specifies weekly rotation of @var{%rotated-files} and
12496 a couple of other files.
12499 @defvr {Scheme Variable} %rotated-files
12500 The list of syslog-controlled files to be rotated. By default it is:
12501 @code{'("/var/log/messages" "/var/log/secure")}.
12504 @node Networking Services
12505 @subsection Networking Services
12507 The @code{(gnu services networking)} module provides services to configure
12508 the network interface.
12510 @cindex DHCP, networking service
12511 @defvr {Scheme Variable} dhcp-client-service-type
12512 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
12513 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
12514 is the DHCP client package to use, @code{isc-dhcp} by default.
12517 @deffn {Scheme Procedure} dhcpd-service-type
12518 This type defines a service that runs a DHCP daemon. To create a
12519 service of this type, you must supply a @code{<dhcpd-configuration>}.
12523 (service dhcpd-service-type
12524 (dhcpd-configuration
12525 (config-file (local-file "my-dhcpd.conf"))
12526 (interfaces '("enp0s25"))))
12530 @deftp {Data Type} dhcpd-configuration
12532 @item @code{package} (default: @code{isc-dhcp})
12533 The package that provides the DHCP daemon. This package is expected to
12534 provide the daemon at @file{sbin/dhcpd} relative to its output
12535 directory. The default package is the
12536 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
12537 @item @code{config-file} (default: @code{#f})
12538 The configuration file to use. This is required. It will be passed to
12539 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
12540 object (@pxref{G-Expressions, file-like objects}). See @code{man
12541 dhcpd.conf} for details on the configuration file syntax.
12542 @item @code{version} (default: @code{"4"})
12543 The DHCP version to use. The ISC DHCP server supports the values ``4'',
12544 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
12545 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
12547 @item @code{run-directory} (default: @code{"/run/dhcpd"})
12548 The run directory to use. At service activation time, this directory
12549 will be created if it does not exist.
12550 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
12551 The PID file to use. This corresponds to the @code{-pf} option of
12552 @code{dhcpd}. See @code{man dhcpd} for details.
12553 @item @code{interfaces} (default: @code{'()})
12554 The names of the network interfaces on which dhcpd should listen for
12555 broadcasts. If this list is not empty, then its elements (which must be
12556 strings) will be appended to the @code{dhcpd} invocation when starting
12557 the daemon. It may not be necessary to explicitly specify any
12558 interfaces here; see @code{man dhcpd} for details.
12562 @defvr {Scheme Variable} static-networking-service-type
12563 This is the type for statically-configured network interfaces.
12564 @c TODO Document <static-networking> data structures.
12567 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
12568 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
12569 [#:requirement @code{'(udev)}]
12570 Return a service that starts @var{interface} with address @var{ip}. If
12571 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
12572 it must be a string specifying the default network gateway. @var{requirement}
12573 can be used to declare a dependency on another service before configuring the
12576 This procedure can be called several times, one for each network
12577 interface of interest. Behind the scenes what it does is extend
12578 @code{static-networking-service-type} with additional network interfaces
12584 (static-networking-service "eno1" "192.168.1.82"
12585 #:gateway "192.168.1.2"
12586 #:name-servers '("192.168.1.2"))
12593 @cindex network management
12594 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
12595 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
12596 management daemon that aims to simplify wired and wireless networking.
12598 This service adds the @var{wicd} package to the global profile, providing
12599 several commands to interact with the daemon and configure networking:
12600 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
12601 and @command{wicd-curses} user interfaces.
12604 @cindex ModemManager
12606 @defvr {Scheme Variable} modem-manager-service-type
12607 This is the service type for the
12608 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
12609 service. The value for this service type is a
12610 @code{modem-manager-configuration} record.
12612 This service is part of @code{%desktop-services} (@pxref{Desktop
12616 @deftp {Data Type} modem-manager-configuration
12617 Data type representing the configuration of ModemManager.
12620 @item @code{modem-manager} (default: @code{modem-manager})
12621 The ModemManager package to use.
12626 @cindex NetworkManager
12628 @defvr {Scheme Variable} network-manager-service-type
12629 This is the service type for the
12630 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
12631 service. The value for this service type is a
12632 @code{network-manager-configuration} record.
12634 This service is part of @code{%desktop-services} (@pxref{Desktop
12638 @deftp {Data Type} network-manager-configuration
12639 Data type representing the configuration of NetworkManager.
12642 @item @code{network-manager} (default: @code{network-manager})
12643 The NetworkManager package to use.
12645 @item @code{dns} (default: @code{"default"})
12646 Processing mode for DNS, which affects how NetworkManager uses the
12647 @code{resolv.conf} configuration file.
12651 NetworkManager will update @code{resolv.conf} to reflect the nameservers
12652 provided by currently active connections.
12655 NetworkManager will run @code{dnsmasq} as a local caching nameserver,
12656 using a "split DNS" configuration if you are connected to a VPN, and
12657 then update @code{resolv.conf} to point to the local nameserver.
12660 NetworkManager will not modify @code{resolv.conf}.
12663 @item @code{vpn-plugins} (default: @code{'()})
12664 This is the list of available plugins for virtual private networks
12665 (VPNs). An example of this is the @code{network-manager-openvpn}
12666 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
12672 @deffn {Scheme Variable} connman-service-type
12673 This is the service type to run @url{https://01.org/connman,Connman},
12674 a network connection manager.
12676 Its value must be an
12677 @code{connman-configuration} record as in this example:
12680 (service connman-service-type
12681 (connman-configuration
12682 (disable-vpn? #t)))
12685 See below for details about @code{connman-configuration}.
12688 @deftp {Data Type} connman-configuration
12689 Data Type representing the configuration of connman.
12692 @item @code{connman} (default: @var{connman})
12693 The connman package to use.
12695 @item @code{disable-vpn?} (default: @code{#f})
12696 When true, disable connman's vpn plugin.
12700 @cindex WPA Supplicant
12701 @defvr {Scheme Variable} wpa-supplicant-service-type
12702 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
12703 supplicant}, an authentication daemon required to authenticate against
12704 encrypted WiFi or ethernet networks.
12707 @deftp {Data Type} wpa-supplicant-configuration
12708 Data type representing the configuration of WPA Supplicant.
12710 It takes the following parameters:
12713 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
12714 The WPA Supplicant package to use.
12716 @item @code{dbus?} (default: @code{#t})
12717 Whether to listen for requests on D-Bus.
12719 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
12720 Where to store the PID file.
12722 @item @code{interface} (default: @code{#f})
12723 If this is set, it must specify the name of a network interface that
12724 WPA supplicant will control.
12726 @item @code{config-file} (default: @code{#f})
12727 Optional configuration file to use.
12729 @item @code{extra-options} (default: @code{'()})
12730 List of additional command-line arguments to pass to the daemon.
12735 @defvr {Scheme Variable} iptables-service-type
12736 This is the service type to set up an iptables configuration. iptables is a
12737 packet filtering framework supported by the Linux kernel. This service
12738 supports configuring iptables for both IPv4 and IPv6. A simple example
12739 configuration rejecting all incoming connections except those to the ssh port
12743 (service iptables-service-type
12744 (iptables-configuration
12745 (ipv4-rules (plain-file "iptables.rules" "*filter
12749 -A INPUT -p tcp --dport 22 -j ACCEPT
12750 -A INPUT -j REJECT --reject-with icmp-port-unreachable
12753 (ipv6-rules (plain-file "ip6tables.rules" "*filter
12757 -A INPUT -p tcp --dport 22 -j ACCEPT
12758 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
12764 @deftp {Data Type} iptables-configuration
12765 The data type representing the configuration of iptables.
12768 @item @code{iptables} (default: @code{iptables})
12769 The iptables package that provides @code{iptables-restore} and
12770 @code{ip6tables-restore}.
12771 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
12772 The iptables rules to use. It will be passed to @code{iptables-restore}.
12773 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
12775 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
12776 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
12777 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
12782 @cindex NTP (Network Time Protocol), service
12783 @cindex real time clock
12784 @defvr {Scheme Variable} ntp-service-type
12785 This is the type of the service running the @uref{http://www.ntp.org,
12786 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
12787 system clock synchronized with that of the specified NTP servers.
12789 The value of this service is an @code{ntpd-configuration} object, as described
12793 @deftp {Data Type} ntp-configuration
12794 This is the data type for the NTP service configuration.
12797 @item @code{servers} (default: @code{%ntp-servers})
12798 This is the list of servers (host names) with which @command{ntpd} will be
12801 @item @code{allow-large-adjustment?} (default: @code{#f})
12802 This determines whether @command{ntpd} is allowed to make an initial
12803 adjustment of more than 1,000 seconds.
12805 @item @code{ntp} (default: @code{ntp})
12806 The NTP package to use.
12810 @defvr {Scheme Variable} %ntp-servers
12811 List of host names used as the default NTP servers. These are servers of the
12812 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
12816 @deffn {Scheme Procedure} openntpd-service-type
12817 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
12818 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
12819 clock synchronized with that of the given servers.
12823 openntpd-service-type
12824 (openntpd-configuration
12825 (listen-on '("127.0.0.1" "::1"))
12826 (sensor '("udcf0 correction 70000"))
12827 (constraint-from '("www.gnu.org"))
12828 (constraints-from '("https://www.google.com/"))
12829 (allow-large-adjustment? #t)))
12834 @deftp {Data Type} openntpd-configuration
12836 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
12837 The openntpd executable to use.
12838 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
12839 A list of local IP addresses or hostnames the ntpd daemon should listen on.
12840 @item @code{query-from} (default: @code{'()})
12841 A list of local IP address the ntpd daemon should use for outgoing queries.
12842 @item @code{sensor} (default: @code{'()})
12843 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
12844 will listen to each sensor that actually exists and ignore non-existent ones.
12845 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
12847 @item @code{server} (default: @var{%ntp-servers})
12848 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
12849 @item @code{servers} (default: @code{'()})
12850 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
12851 @item @code{constraint-from} (default: @code{'()})
12852 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
12853 This time information is not used for precision but acts as an authenticated
12854 constraint, thereby reducing the impact of unauthenticated NTP
12855 man-in-the-middle attacks.
12856 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
12858 @item @code{constraints-from} (default: @code{'()})
12859 As with constraint from, specify a list of URLs, IP addresses or hostnames of
12860 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
12861 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
12862 @item @code{allow-large-adjustment?} (default: @code{#f})
12863 Determines if @code{ntpd} is allowed to make an initial adjustment of more
12869 @deffn {Scheme variable} inetd-service-type
12870 This service runs the @command{inetd} (@pxref{inetd invocation,,,
12871 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
12872 connections on internet sockets, and lazily starts the specified server
12873 program when a connection is made on one of these sockets.
12875 The value of this service is an @code{inetd-configuration} object. The
12876 following example configures the @command{inetd} daemon to provide the
12877 built-in @command{echo} service, as well as an smtp service which
12878 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
12879 gateway @code{hostname}:
12884 (inetd-configuration
12888 (socket-type 'stream)
12895 (socket-type 'stream)
12899 (program (file-append openssh "/bin/ssh"))
12901 '("ssh" "-qT" "-i" "/path/to/ssh_key"
12902 "-W" "smtp-server:25" "user@@hostname")))))
12905 See below for more details about @code{inetd-configuration}.
12908 @deftp {Data Type} inetd-configuration
12909 Data type representing the configuration of @command{inetd}.
12912 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
12913 The @command{inetd} executable to use.
12915 @item @code{entries} (default: @code{'()})
12916 A list of @command{inetd} service entries. Each entry should be created
12917 by the @code{inetd-entry} constructor.
12921 @deftp {Data Type} inetd-entry
12922 Data type representing an entry in the @command{inetd} configuration.
12923 Each entry corresponds to a socket where @command{inetd} will listen for
12927 @item @code{node} (default: @code{#f})
12928 Optional string, a comma-separated list of local addresses
12929 @command{inetd} should use when listening for this service.
12930 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
12931 description of all options.
12933 A string, the name must correspond to an entry in @code{/etc/services}.
12934 @item @code{socket-type}
12935 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
12937 @item @code{protocol}
12938 A string, must correspond to an entry in @code{/etc/protocols}.
12939 @item @code{wait?} (default: @code{#t})
12940 Whether @command{inetd} should wait for the server to exit before
12941 listening to new service requests.
12943 A string containing the user (and, optionally, group) name of the user
12944 as whom the server should run. The group name can be specified in a
12945 suffix, separated by a colon or period, i.e.@: @code{"user"},
12946 @code{"user:group"} or @code{"user.group"}.
12947 @item @code{program} (default: @code{"internal"})
12948 The server program which will serve the requests, or @code{"internal"}
12949 if @command{inetd} should use a built-in service.
12950 @item @code{arguments} (default: @code{'()})
12951 A list strings or file-like objects, which are the server program's
12952 arguments, starting with the zeroth argument, i.e.@: the name of the
12953 program itself. For @command{inetd}'s internal services, this entry
12954 must be @code{'()} or @code{'("internal")}.
12957 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
12958 detailed discussion of each configuration field.
12962 @defvr {Scheme Variable} tor-service-type
12963 This is the type for a service that runs the @uref{https://torproject.org,
12964 Tor} anonymous networking daemon. The service is configured using a
12965 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
12966 @code{tor} unprivileged user, which is a member of the @code{tor} group.
12970 @deftp {Data Type} tor-configuration
12972 @item @code{tor} (default: @code{tor})
12973 The package that provides the Tor daemon. This package is expected to provide
12974 the daemon at @file{bin/tor} relative to its output directory. The default
12975 package is the @uref{https://www.torproject.org, Tor Project's}
12978 @item @code{config-file} (default: @code{(plain-file "empty" "")})
12979 The configuration file to use. It will be appended to a default configuration
12980 file, and the final configuration file will be passed to @code{tor} via its
12981 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
12982 file-like objects}). See @code{man tor} for details on the configuration file
12985 @item @code{hidden-services} (default: @code{'()})
12986 The list of @code{<hidden-service>} records to use. For any hidden service
12987 you include in this list, appropriate configuration to enable the hidden
12988 service will be automatically added to the default configuration file. You
12989 may conveniently create @code{<hidden-service>} records using the
12990 @code{tor-hidden-service} procedure described below.
12992 @item @code{socks-socket-type} (default: @code{'tcp})
12993 The default socket type that Tor should use for its SOCKS socket. This must
12994 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
12995 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
12996 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
12997 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13000 If you want to customize the SOCKS socket in more detail, leave
13001 @code{socks-socket-type} at its default value of @code{'tcp} and use
13002 @code{config-file} to override the default by providing your own
13003 @code{SocksPort} option.
13007 @cindex hidden service
13008 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13009 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13010 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13013 '((22 "127.0.0.1:22")
13014 (80 "127.0.0.1:8080"))
13017 In this example, port 22 of the hidden service is mapped to local port 22, and
13018 port 80 is mapped to local port 8080.
13020 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13021 the @file{hostname} file contains the @code{.onion} host name for the hidden
13024 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13025 project's documentation} for more information.
13028 The @code{(gnu services rsync)} module provides the following services:
13030 You might want an rsync daemon if you have files that you want available
13031 so anyone (or just yourself) can download existing files or upload new
13034 @deffn {Scheme Variable} rsync-service-type
13035 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13036 The value for this service type is a
13037 @command{rsync-configuration} record as in this example:
13040 (service rsync-service-type)
13043 See below for details about @code{rsync-configuration}.
13046 @deftp {Data Type} rsync-configuration
13047 Data type representing the configuration for @code{rsync-service}.
13050 @item @code{package} (default: @var{rsync})
13051 @code{rsync} package to use.
13053 @item @code{port-number} (default: @code{873})
13054 TCP port on which @command{rsync} listens for incoming connections. If port
13055 is less than @code{1024} @command{rsync} needs to be started as the
13056 @code{root} user and group.
13058 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
13059 Name of the file where @command{rsync} writes its PID.
13061 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
13062 Name of the file where @command{rsync} writes its lock file.
13064 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
13065 Name of the file where @command{rsync} writes its log file.
13067 @item @code{use-chroot?} (default: @var{#t})
13068 Whether to use chroot for @command{rsync} shared directory.
13070 @item @code{share-path} (default: @file{/srv/rsync})
13071 Location of the @command{rsync} shared directory.
13073 @item @code{share-comment} (default: @code{"Rsync share"})
13074 Comment of the @command{rsync} shared directory.
13076 @item @code{read-only?} (default: @var{#f})
13077 Read-write permissions to shared directory.
13079 @item @code{timeout} (default: @code{300})
13080 I/O timeout in seconds.
13082 @item @code{user} (default: @var{"root"})
13083 Owner of the @code{rsync} process.
13085 @item @code{group} (default: @var{"root"})
13086 Group of the @code{rsync} process.
13088 @item @code{uid} (default: @var{"rsyncd"})
13089 User name or user ID that file transfers to and from that module should take
13090 place as when the daemon was run as @code{root}.
13092 @item @code{gid} (default: @var{"rsyncd"})
13093 Group name or group ID that will be used when accessing the module.
13098 Furthermore, @code{(gnu services ssh)} provides the following services.
13102 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
13103 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
13104 [#:allow-empty-passwords? #f] [#:root-login? #f] @
13105 [#:syslog-output? #t] [#:x11-forwarding? #t] @
13106 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
13107 [#:public-key-authentication? #t] [#:initialize? #t]
13108 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
13109 @var{host-key} must designate a file containing the host key, and readable
13112 When @var{daemonic?} is true, @command{lshd} will detach from the
13113 controlling terminal and log its output to syslogd, unless one sets
13114 @var{syslog-output?} to false. Obviously, it also makes lsh-service
13115 depend on existence of syslogd service. When @var{pid-file?} is true,
13116 @command{lshd} writes its PID to the file called @var{pid-file}.
13118 When @var{initialize?} is true, automatically create the seed and host key
13119 upon service activation if they do not exist yet. This may take long and
13120 require interaction.
13122 When @var{initialize?} is false, it is up to the user to initialize the
13123 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
13124 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
13125 basics,,, lsh, LSH Manual}).
13127 When @var{interfaces} is empty, lshd listens for connections on all the
13128 network interfaces; otherwise, @var{interfaces} must be a list of host names
13131 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
13132 passwords, and @var{root-login?} specifies whether to accept log-ins as
13135 The other options should be self-descriptive.
13140 @deffn {Scheme Variable} openssh-service-type
13141 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
13142 shell daemon, @command{sshd}. Its value must be an
13143 @code{openssh-configuration} record as in this example:
13146 (service openssh-service-type
13147 (openssh-configuration
13148 (x11-forwarding? #t)
13149 (permit-root-login 'without-password)
13151 `(("alice" ,(local-file "alice.pub"))
13152 ("bob" ,(local-file "bob.pub"))))))
13155 See below for details about @code{openssh-configuration}.
13157 This service can be extended with extra authorized keys, as in this
13161 (service-extension openssh-service-type
13162 (const `(("charlie"
13163 ,(local-file "charlie.pub")))))
13167 @deftp {Data Type} openssh-configuration
13168 This is the configuration record for OpenSSH's @command{sshd}.
13171 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
13172 Name of the file where @command{sshd} writes its PID.
13174 @item @code{port-number} (default: @code{22})
13175 TCP port on which @command{sshd} listens for incoming connections.
13177 @item @code{permit-root-login} (default: @code{#f})
13178 This field determines whether and when to allow logins as root. If
13179 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
13180 If it's the symbol @code{'without-password}, then root logins are
13181 permitted but not with password-based authentication.
13183 @item @code{allow-empty-passwords?} (default: @code{#f})
13184 When true, users with empty passwords may log in. When false, they may
13187 @item @code{password-authentication?} (default: @code{#t})
13188 When true, users may log in with their password. When false, they have
13189 other authentication methods.
13191 @item @code{public-key-authentication?} (default: @code{#t})
13192 When true, users may log in using public key authentication. When
13193 false, users have to use other authentication method.
13195 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
13196 This is used only by protocol version 2.
13198 @item @code{x11-forwarding?} (default: @code{#f})
13199 When true, forwarding of X11 graphical client connections is
13200 enabled---in other words, @command{ssh} options @option{-X} and
13201 @option{-Y} will work.
13203 @item @code{allow-agent-forwarding?} (default: @code{#t})
13204 Whether to allow agent forwarding.
13206 @item @code{allow-tcp-forwarding?} (default: @code{#t})
13207 Whether to allow TCP forwarding.
13209 @item @code{gateway-ports?} (default: @code{#f})
13210 Whether to allow gateway ports.
13212 @item @code{challenge-response-authentication?} (default: @code{#f})
13213 Specifies whether challenge response authentication is allowed (e.g.@: via
13216 @item @code{use-pam?} (default: @code{#t})
13217 Enables the Pluggable Authentication Module interface. If set to
13218 @code{#t}, this will enable PAM authentication using
13219 @code{challenge-response-authentication?} and
13220 @code{password-authentication?}, in addition to PAM account and session
13221 module processing for all authentication types.
13223 Because PAM challenge response authentication usually serves an
13224 equivalent role to password authentication, you should disable either
13225 @code{challenge-response-authentication?} or
13226 @code{password-authentication?}.
13228 @item @code{print-last-log?} (default: @code{#t})
13229 Specifies whether @command{sshd} should print the date and time of the
13230 last user login when a user logs in interactively.
13232 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
13233 Configures external subsystems (e.g.@: file transfer daemon).
13235 This is a list of two-element lists, each of which containing the
13236 subsystem name and a command (with optional arguments) to execute upon
13239 The command @command{internal-sftp} implements an in-process SFTP
13240 server. Alternately, one can specify the @command{sftp-server} command:
13242 (service openssh-service-type
13243 (openssh-configuration
13245 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
13248 @item @code{accepted-environment} (default: @code{'()})
13249 List of strings describing which environment variables may be exported.
13251 Each string gets on its own line. See the @code{AcceptEnv} option in
13252 @code{man sshd_config}.
13254 This example allows ssh-clients to export the @code{COLORTERM} variable.
13255 It is set by terminal emulators, which support colors. You can use it in
13256 your shell's ressource file to enable colors for the prompt and commands
13257 if this variable is set.
13260 (service openssh-service-type
13261 (openssh-configuration
13262 (accepted-environment '("COLORTERM"))))
13265 @item @code{authorized-keys} (default: @code{'()})
13266 @cindex authorized keys, SSH
13267 @cindex SSH authorized keys
13268 This is the list of authorized keys. Each element of the list is a user
13269 name followed by one or more file-like objects that represent SSH public
13273 (openssh-configuration
13275 `(("rekado" ,(local-file "rekado.pub"))
13276 ("chris" ,(local-file "chris.pub"))
13277 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
13281 registers the specified public keys for user accounts @code{rekado},
13282 @code{chris}, and @code{root}.
13284 Additional authorized keys can be specified @i{via}
13285 @code{service-extension}.
13287 Note that this does @emph{not} interfere with the use of
13288 @file{~/.ssh/authorized_keys}.
13290 @item @code{log-level} (default: @code{'info})
13291 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
13292 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
13293 page for @file{sshd_config} for the full list of level names.
13295 @item @code{extra-content} (default: @code{""})
13296 This field can be used to append arbitrary text to the configuration file. It
13297 is especially useful for elaborate configurations that cannot be expressed
13298 otherwise. This configuration, for example, would generally disable root
13299 logins, but permit them from one specific IP address:
13302 (openssh-configuration
13304 Match Address 192.168.0.1
13305 PermitRootLogin yes"))
13311 @deffn {Scheme Procedure} dropbear-service [@var{config}]
13312 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
13313 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
13316 For example, to specify a Dropbear service listening on port 1234, add
13317 this call to the operating system's @code{services} field:
13320 (dropbear-service (dropbear-configuration
13321 (port-number 1234)))
13325 @deftp {Data Type} dropbear-configuration
13326 This data type represents the configuration of a Dropbear SSH daemon.
13329 @item @code{dropbear} (default: @var{dropbear})
13330 The Dropbear package to use.
13332 @item @code{port-number} (default: 22)
13333 The TCP port where the daemon waits for incoming connections.
13335 @item @code{syslog-output?} (default: @code{#t})
13336 Whether to enable syslog output.
13338 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
13339 File name of the daemon's PID file.
13341 @item @code{root-login?} (default: @code{#f})
13342 Whether to allow @code{root} logins.
13344 @item @code{allow-empty-passwords?} (default: @code{#f})
13345 Whether to allow empty passwords.
13347 @item @code{password-authentication?} (default: @code{#t})
13348 Whether to enable password-based authentication.
13352 @defvr {Scheme Variable} %facebook-host-aliases
13353 This variable contains a string for use in @file{/etc/hosts}
13354 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
13355 line contains a entry that maps a known server name of the Facebook
13356 on-line service---e.g., @code{www.facebook.com}---to the local
13357 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
13359 This variable is typically used in the @code{hosts-file} field of an
13360 @code{operating-system} declaration (@pxref{operating-system Reference,
13361 @file{/etc/hosts}}):
13364 (use-modules (gnu) (guix))
13367 (host-name "mymachine")
13370 ;; Create a /etc/hosts file with aliases for "localhost"
13371 ;; and "mymachine", as well as for Facebook servers.
13372 (plain-file "hosts"
13373 (string-append (local-host-aliases host-name)
13374 %facebook-host-aliases))))
13377 This mechanism can prevent programs running locally, such as Web
13378 browsers, from accessing Facebook.
13381 The @code{(gnu services avahi)} provides the following definition.
13383 @defvr {Scheme Variable} avahi-service-type
13384 This is the service that runs @command{avahi-daemon}, a system-wide
13385 mDNS/DNS-SD responder that allows for service discovery and
13386 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
13387 Its value must be a @code{zero-configuration} record---see below.
13389 This service extends the name service cache daemon (nscd) so that it can
13390 resolve @code{.local} host names using
13391 @uref{http://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
13392 Service Switch}, for information on host name resolution.
13394 Additionally, add the @var{avahi} package to the system profile so that
13395 commands such as @command{avahi-browse} are directly usable.
13398 @deftp {Data Type} avahi-configuration
13399 Data type representation the configuration for Avahi.
13403 @item @code{host-name} (default: @code{#f})
13404 If different from @code{#f}, use that as the host name to
13405 publish for this machine; otherwise, use the machine's actual host name.
13407 @item @code{publish?} (default: @code{#t})
13408 When true, allow host names and services to be published (broadcast) over the
13411 @item @code{publish-workstation?} (default: @code{#t})
13412 When true, @command{avahi-daemon} publishes the machine's host name and IP
13413 address via mDNS on the local network. To view the host names published on
13414 your local network, you can run:
13417 avahi-browse _workstation._tcp
13420 @item @code{wide-area?} (default: @code{#f})
13421 When true, DNS-SD over unicast DNS is enabled.
13423 @item @code{ipv4?} (default: @code{#t})
13424 @itemx @code{ipv6?} (default: @code{#t})
13425 These fields determine whether to use IPv4/IPv6 sockets.
13427 @item @code{domains-to-browse} (default: @code{'()})
13428 This is a list of domains to browse.
13432 @deffn {Scheme Variable} openvswitch-service-type
13433 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
13434 service, whose value should be an @code{openvswitch-configuration}
13438 @deftp {Data Type} openvswitch-configuration
13439 Data type representing the configuration of Open vSwitch, a multilayer
13440 virtual switch which is designed to enable massive network automation
13441 through programmatic extension.
13444 @item @code{package} (default: @var{openvswitch})
13445 Package object of the Open vSwitch.
13451 @subsection X Window
13454 @cindex X Window System
13455 @cindex login manager
13456 Support for the X Window graphical display system---specifically
13457 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
13458 there is no @code{xorg-service} procedure. Instead, the X server is
13459 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
13462 @cindex GNOME, login manager
13463 GDM of course allows users to log in into window managers and desktop
13464 environments other than GNOME; for those using GNOME, GDM is required for
13465 features such as automatic screen locking.
13467 @cindex window manager
13468 To use X11, you must install at least one @dfn{window manager}---for
13469 example the @code{windowmaker} or @code{openbox} packages---preferably
13470 by adding it to the @code{packages} field of your operating system
13471 definition (@pxref{operating-system Reference, system-wide packages}).
13473 @defvr {Scheme Variable} gdm-service-type
13474 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
13475 Desktop Manager} (GDM), a program that manages graphical display servers and
13476 handles graphical user logins. Its value must be a @code{gdm-configuration}
13479 @cindex session types (X11)
13480 @cindex X11 session types
13481 GDM looks for @dfn{session types} described by the @file{.desktop} files in
13482 @file{/run/current-system/profile/share/xsessions} and allows users to choose
13483 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
13484 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
13485 set of packages automatically makes them available at the log-in screen.
13487 In addition, @file{~/.xsession} files are honored. When available,
13488 @file{~/.xsession} must be an executable that starts a window manager
13489 and/or other X clients.
13492 @deftp {Data Type} gdm-configuration
13494 @item @code{auto-login?} (default: @code{#f})
13495 @itemx @code{default-user} (default: @code{#f})
13496 When @code{auto-login?} is false, GDM presents a log-in screen.
13498 When @code{auto-login?} is true, GDM logs in directly as
13499 @code{default-user}.
13501 @item @code{gnome-shell-assets} (default: ...)
13502 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
13504 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
13505 Configuration of the Xorg graphical server.
13507 @item @code{xsession} (default: @code{(xinitrc)})
13508 Script to run before starting a X session.
13510 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
13511 File name of the @code{dbus-daemon} executable.
13513 @item @code{gdm} (default: @code{gdm})
13514 The GDM package to use.
13518 @defvr {Scheme Variable} slim-service-type
13519 This is the type for the SLiM graphical login manager for X11.
13521 Like GDM, SLiM looks for session types described by @file{.desktop} files and
13522 allows users to choose a session from the log-in screen using @kbd{F1}. It
13523 also honors @file{~/.xsession} files.
13525 Unlike GDM, SLiM does not spawn the user session on a different VT after
13526 logging in, which means that you can only start one graphical session. If you
13527 want to be able to run multiple graphical sessions at the same time you have
13528 to add multiple SLiM services to your system services. The following example
13529 shows how to replace the default GDM service with two SLiM services on tty7
13533 (use-modules (gnu services)
13534 (gnu services desktop)
13535 (gnu services xorg)
13536 (srfi srfi-1)) ;for 'remove'
13540 (services (cons* (service slim-service-type (slim-configuration
13543 (service slim-service-type (slim-configuration
13546 (remove (lambda (service)
13547 (eq? (service-kind service) gdm-service-type))
13548 %desktop-services))))
13553 @deftp {Data Type} slim-configuration
13554 Data type representing the configuration of @code{slim-service-type}.
13557 @item @code{allow-empty-passwords?} (default: @code{#t})
13558 Whether to allow logins with empty passwords.
13560 @item @code{auto-login?} (default: @code{#f})
13561 @itemx @code{default-user} (default: @code{""})
13562 When @code{auto-login?} is false, SLiM presents a log-in screen.
13564 When @code{auto-login?} is true, SLiM logs in directly as
13565 @code{default-user}.
13567 @item @code{theme} (default: @code{%default-slim-theme})
13568 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
13569 The graphical theme to use and its name.
13571 @item @code{auto-login-session} (default: @code{#f})
13572 If true, this must be the name of the executable to start as the default
13573 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
13575 If false, a session described by one of the available @file{.desktop}
13576 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
13580 You must install at least one window manager in the system profile or in
13581 your user profile. Failing to do that, if @code{auto-login-session} is
13582 false, you will be unable to log in.
13585 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13586 Configuration of the Xorg graphical server.
13588 @item @code{display} (default @code{":0"})
13589 The display on which to start the Xorg graphical server.
13591 @item @code{vt} (default @code{"vt7"})
13592 The VT on which to start the Xorg graphical server.
13594 @item @code{xauth} (default: @code{xauth})
13595 The XAuth package to use.
13597 @item @code{shepherd} (default: @code{shepherd})
13598 The Shepherd package used when invoking @command{halt} and
13601 @item @code{sessreg} (default: @code{sessreg})
13602 The sessreg package used in order to register the session.
13604 @item @code{slim} (default: @code{slim})
13605 The SLiM package to use.
13609 @defvr {Scheme Variable} %default-theme
13610 @defvrx {Scheme Variable} %default-theme-name
13611 The default SLiM theme and its name.
13615 @deftp {Data Type} sddm-configuration
13616 This is the data type representing the sddm service configuration.
13619 @item @code{display-server} (default: "x11")
13620 Select display server to use for the greeter. Valid values are "x11"
13623 @item @code{numlock} (default: "on")
13624 Valid values are "on", "off" or "none".
13626 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
13627 Command to run when halting.
13629 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
13630 Command to run when rebooting.
13632 @item @code{theme} (default "maldives")
13633 Theme to use. Default themes provided by SDDM are "elarun" or "maldives".
13635 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
13636 Directory to look for themes.
13638 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
13639 Directory to look for faces.
13641 @item @code{default-path} (default "/run/current-system/profile/bin")
13642 Default PATH to use.
13644 @item @code{minimum-uid} (default: 1000)
13645 Minimum UID displayed in SDDM and allowed for log-in.
13647 @item @code{maximum-uid} (default: 2000)
13648 Maximum UID to display in SDDM.
13650 @item @code{remember-last-user?} (default #t)
13651 Remember last user.
13653 @item @code{remember-last-session?} (default #t)
13654 Remember last session.
13656 @item @code{hide-users} (default "")
13657 Usernames to hide from SDDM greeter.
13659 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
13660 Users with shells listed will be hidden from the SDDM greeter.
13662 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
13663 Script to run before starting a wayland session.
13665 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
13666 Directory to look for desktop files starting wayland sessions.
13668 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13669 Configuration of the Xorg graphical server.
13671 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
13674 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
13677 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
13678 Script to run after starting xorg-server.
13680 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
13681 Script to run before stopping xorg-server.
13683 @item @code{xsession-command} (default: @code{xinitrc})
13684 Script to run before starting a X session.
13686 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
13687 Directory to look for desktop files starting X sessions.
13689 @item @code{minimum-vt} (default: 7)
13692 @item @code{auto-login-user} (default "")
13693 User to use for auto-login.
13695 @item @code{auto-login-session} (default "")
13696 Desktop file to use for auto-login.
13698 @item @code{relogin?} (default #f)
13699 Relogin after logout.
13704 @cindex login manager
13706 @deffn {Scheme Procedure} sddm-service config
13707 Return a service that spawns the SDDM graphical login manager for config of
13708 type @code{<sddm-configuration>}.
13711 (sddm-service (sddm-configuration
13712 (auto-login-user "Alice")
13713 (auto-login-session "xfce.desktop")))
13717 @cindex Xorg, configuration
13718 @deftp {Data Type} xorg-configuration
13719 This data type represents the configuration of the Xorg graphical display
13720 server. Note that there is not Xorg service; instead, the X server is started
13721 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
13722 of these display managers aggregates an @code{xorg-configuration} record.
13725 @item @code{modules} (default: @code{%default-xorg-modules})
13726 This is a list of @dfn{module packages} loaded by the Xorg
13727 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
13729 @item @code{fonts} (default: @code{%default-xorg-fonts})
13730 This is a list of font directories to add to the server's @dfn{font path}.
13732 @item @code{drivers} (default: @code{'()})
13733 This must be either the empty list, in which case Xorg chooses a graphics
13734 driver automatically, or a list of driver names that will be tried in this
13735 order---e.g., @code{("modesetting" "vesa")}.
13737 @item @code{resolutions} (default: @code{'()})
13738 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
13739 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
13742 @cindex keyboard layout, for Xorg
13743 @cindex keymap, for Xorg
13744 @item @code{keyboard-layout} (default: @code{#f})
13745 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
13746 English (``qwerty'') for a 105-key PC keyboard.
13748 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
13749 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
13750 information on how to specify the keyboard layout.
13752 @item @code{extra-config} (default: @code{'()})
13753 This is a list of strings or objects appended to the configuration file. It
13754 is used to pass extra text to be added verbatim to the configuration file.
13756 @item @code{server} (default: @code{xorg-server})
13757 This is the package providing the Xorg server.
13759 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
13760 This is the list of command-line arguments to pass to the X server. The
13761 default is @code{-nolisten tcp}.
13765 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
13766 [@var{login-manager-service-type}]
13767 Tell the log-in manager (of type @var{login-manager-service-type}) to use
13768 @var{config}, an @code{<xorg-configuration>} record.
13770 Since the Xorg configuration is embedded in the log-in manager's
13771 configuration---e.g., @code{gdm-configuration}---this procedure provides a
13772 shorthand to set the Xorg configuration.
13775 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
13776 Return a @code{startx} script in which the modules, fonts, etc. specified
13777 in @var{config}, are available. The result should be used in place of
13780 Usually the X server is started by a login manager.
13784 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
13785 Add @var{package}, a package for a screen locker or screen saver whose
13786 command is @var{program}, to the set of setuid programs and add a PAM entry
13787 for it. For example:
13790 (screen-locker-service xlockmore "xlock")
13793 makes the good ol' XlockMore usable.
13797 @node Printing Services
13798 @subsection Printing Services
13800 @cindex printer support with CUPS
13801 The @code{(gnu services cups)} module provides a Guix service definition
13802 for the CUPS printing service. To add printer support to a Guix
13803 system, add a @code{cups-service} to the operating system definition:
13805 @deffn {Scheme Variable} cups-service-type
13806 The service type for the CUPS print server. Its value should be a valid
13807 CUPS configuration (see below). To use the default settings, simply
13810 (service cups-service-type)
13814 The CUPS configuration controls the basic things about your CUPS
13815 installation: what interfaces it listens on, what to do if a print job
13816 fails, how much logging to do, and so on. To actually add a printer,
13817 you have to visit the @url{http://localhost:631} URL, or use a tool such
13818 as GNOME's printer configuration services. By default, configuring a
13819 CUPS service will generate a self-signed certificate if needed, for
13820 secure connections to the print server.
13822 Suppose you want to enable the Web interface of CUPS and also add
13823 support for Epson printers @i{via} the @code{escpr} package and for HP
13824 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
13825 like this (you need to use the @code{(gnu packages cups)} module):
13828 (service cups-service-type
13829 (cups-configuration
13830 (web-interface? #t)
13832 (list cups-filters escpr hplip-minimal))))
13835 Note: If you wish to use the Qt5 based GUI which comes with the hplip
13836 package then it is suggested that you install the @code{hplip} package,
13837 either in your OS configuration file or as your user.
13839 The available configuration parameters follow. Each parameter
13840 definition is preceded by its type; for example, @samp{string-list foo}
13841 indicates that the @code{foo} parameter should be specified as a list of
13842 strings. There is also a way to specify the configuration as a string,
13843 if you have an old @code{cupsd.conf} file that you want to port over
13844 from some other system; see the end for more details.
13846 @c The following documentation was initially generated by
13847 @c (generate-documentation) in (gnu services cups). Manually maintained
13848 @c documentation is better, so we shouldn't hesitate to edit below as
13849 @c needed. However if the change you want to make to this documentation
13850 @c can be done in an automated way, it's probably easier to change
13851 @c (generate-documentation) than to make it below and have to deal with
13852 @c the churn as CUPS updates.
13855 Available @code{cups-configuration} fields are:
13857 @deftypevr {@code{cups-configuration} parameter} package cups
13861 @deftypevr {@code{cups-configuration} parameter} package-list extensions
13862 Drivers and other extensions to the CUPS package.
13865 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
13866 Configuration of where to write logs, what directories to use for print
13867 spools, and related privileged configuration parameters.
13869 Available @code{files-configuration} fields are:
13871 @deftypevr {@code{files-configuration} parameter} log-location access-log
13872 Defines the access log filename. Specifying a blank filename disables
13873 access log generation. The value @code{stderr} causes log entries to be
13874 sent to the standard error file when the scheduler is running in the
13875 foreground, or to the system log daemon when run in the background. The
13876 value @code{syslog} causes log entries to be sent to the system log
13877 daemon. The server name may be included in filenames using the string
13878 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
13880 Defaults to @samp{"/var/log/cups/access_log"}.
13883 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
13884 Where CUPS should cache data.
13886 Defaults to @samp{"/var/cache/cups"}.
13889 @deftypevr {@code{files-configuration} parameter} string config-file-perm
13890 Specifies the permissions for all configuration files that the scheduler
13893 Note that the permissions for the printers.conf file are currently
13894 masked to only allow access from the scheduler user (typically root).
13895 This is done because printer device URIs sometimes contain sensitive
13896 authentication information that should not be generally known on the
13897 system. There is no way to disable this security feature.
13899 Defaults to @samp{"0640"}.
13902 @deftypevr {@code{files-configuration} parameter} log-location error-log
13903 Defines the error log filename. Specifying a blank filename disables
13904 error log generation. The value @code{stderr} causes log entries to be
13905 sent to the standard error file when the scheduler is running in the
13906 foreground, or to the system log daemon when run in the background. The
13907 value @code{syslog} causes log entries to be sent to the system log
13908 daemon. The server name may be included in filenames using the string
13909 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
13911 Defaults to @samp{"/var/log/cups/error_log"}.
13914 @deftypevr {@code{files-configuration} parameter} string fatal-errors
13915 Specifies which errors are fatal, causing the scheduler to exit. The
13920 No errors are fatal.
13923 All of the errors below are fatal.
13926 Browsing initialization errors are fatal, for example failed connections
13927 to the DNS-SD daemon.
13930 Configuration file syntax errors are fatal.
13933 Listen or Port errors are fatal, except for IPv6 failures on the
13934 loopback or @code{any} addresses.
13937 Log file creation or write errors are fatal.
13940 Bad startup file permissions are fatal, for example shared TLS
13941 certificate and key files with world-read permissions.
13944 Defaults to @samp{"all -browse"}.
13947 @deftypevr {@code{files-configuration} parameter} boolean file-device?
13948 Specifies whether the file pseudo-device can be used for new printer
13949 queues. The URI @uref{file:///dev/null} is always allowed.
13951 Defaults to @samp{#f}.
13954 @deftypevr {@code{files-configuration} parameter} string group
13955 Specifies the group name or ID that will be used when executing external
13958 Defaults to @samp{"lp"}.
13961 @deftypevr {@code{files-configuration} parameter} string log-file-perm
13962 Specifies the permissions for all log files that the scheduler writes.
13964 Defaults to @samp{"0644"}.
13967 @deftypevr {@code{files-configuration} parameter} log-location page-log
13968 Defines the page log filename. Specifying a blank filename disables
13969 page log generation. The value @code{stderr} causes log entries to be
13970 sent to the standard error file when the scheduler is running in the
13971 foreground, or to the system log daemon when run in the background. The
13972 value @code{syslog} causes log entries to be sent to the system log
13973 daemon. The server name may be included in filenames using the string
13974 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
13976 Defaults to @samp{"/var/log/cups/page_log"}.
13979 @deftypevr {@code{files-configuration} parameter} string remote-root
13980 Specifies the username that is associated with unauthenticated accesses
13981 by clients claiming to be the root user. The default is @code{remroot}.
13983 Defaults to @samp{"remroot"}.
13986 @deftypevr {@code{files-configuration} parameter} file-name request-root
13987 Specifies the directory that contains print jobs and other HTTP request
13990 Defaults to @samp{"/var/spool/cups"}.
13993 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
13994 Specifies the level of security sandboxing that is applied to print
13995 filters, backends, and other child processes of the scheduler; either
13996 @code{relaxed} or @code{strict}. This directive is currently only
13997 used/supported on macOS.
13999 Defaults to @samp{strict}.
14002 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
14003 Specifies the location of TLS certificates and private keys. CUPS will
14004 look for public and private keys in this directory: a @code{.crt} files
14005 for PEM-encoded certificates and corresponding @code{.key} files for
14006 PEM-encoded private keys.
14008 Defaults to @samp{"/etc/cups/ssl"}.
14011 @deftypevr {@code{files-configuration} parameter} file-name server-root
14012 Specifies the directory containing the server configuration files.
14014 Defaults to @samp{"/etc/cups"}.
14017 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
14018 Specifies whether the scheduler calls fsync(2) after writing
14019 configuration or state files.
14021 Defaults to @samp{#f}.
14024 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
14025 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
14028 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
14029 Specifies the directory where temporary files are stored.
14031 Defaults to @samp{"/var/spool/cups/tmp"}.
14034 @deftypevr {@code{files-configuration} parameter} string user
14035 Specifies the user name or ID that is used when running external
14038 Defaults to @samp{"lp"}.
14042 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
14043 Specifies the logging level for the AccessLog file. The @code{config}
14044 level logs when printers and classes are added, deleted, or modified and
14045 when configuration files are accessed or updated. The @code{actions}
14046 level logs when print jobs are submitted, held, released, modified, or
14047 canceled, and any of the conditions for @code{config}. The @code{all}
14048 level logs all requests.
14050 Defaults to @samp{actions}.
14053 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
14054 Specifies whether to purge job history data automatically when it is no
14055 longer required for quotas.
14057 Defaults to @samp{#f}.
14060 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
14061 Specifies which protocols to use for local printer sharing.
14063 Defaults to @samp{dnssd}.
14066 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
14067 Specifies whether the CUPS web interface is advertised.
14069 Defaults to @samp{#f}.
14072 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
14073 Specifies whether shared printers are advertised.
14075 Defaults to @samp{#f}.
14078 @deftypevr {@code{cups-configuration} parameter} string classification
14079 Specifies the security classification of the server. Any valid banner
14080 name can be used, including "classified", "confidential", "secret",
14081 "topsecret", and "unclassified", or the banner can be omitted to disable
14082 secure printing functions.
14084 Defaults to @samp{""}.
14087 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
14088 Specifies whether users may override the classification (cover page) of
14089 individual print jobs using the @code{job-sheets} option.
14091 Defaults to @samp{#f}.
14094 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
14095 Specifies the default type of authentication to use.
14097 Defaults to @samp{Basic}.
14100 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
14101 Specifies whether encryption will be used for authenticated requests.
14103 Defaults to @samp{Required}.
14106 @deftypevr {@code{cups-configuration} parameter} string default-language
14107 Specifies the default language to use for text and web content.
14109 Defaults to @samp{"en"}.
14112 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
14113 Specifies the default paper size for new print queues. @samp{"Auto"}
14114 uses a locale-specific default, while @samp{"None"} specifies there is
14115 no default paper size. Specific size names are typically
14116 @samp{"Letter"} or @samp{"A4"}.
14118 Defaults to @samp{"Auto"}.
14121 @deftypevr {@code{cups-configuration} parameter} string default-policy
14122 Specifies the default access policy to use.
14124 Defaults to @samp{"default"}.
14127 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
14128 Specifies whether local printers are shared by default.
14130 Defaults to @samp{#t}.
14133 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
14134 Specifies the delay for updating of configuration and state files, in
14135 seconds. A value of 0 causes the update to happen as soon as possible,
14136 typically within a few milliseconds.
14138 Defaults to @samp{30}.
14141 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
14142 Specifies what to do when an error occurs. Possible values are
14143 @code{abort-job}, which will discard the failed print job;
14144 @code{retry-job}, which will retry the job at a later time;
14145 @code{retry-this-job}, which retries the failed job immediately; and
14146 @code{stop-printer}, which stops the printer.
14148 Defaults to @samp{stop-printer}.
14151 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
14152 Specifies the maximum cost of filters that are run concurrently, which
14153 can be used to minimize disk, memory, and CPU resource problems. A
14154 limit of 0 disables filter limiting. An average print to a
14155 non-PostScript printer needs a filter limit of about 200. A PostScript
14156 printer needs about half that (100). Setting the limit below these
14157 thresholds will effectively limit the scheduler to printing a single job
14160 Defaults to @samp{0}.
14163 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
14164 Specifies the scheduling priority of filters that are run to print a
14165 job. The nice value ranges from 0, the highest priority, to 19, the
14168 Defaults to @samp{0}.
14171 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
14172 Specifies whether to do reverse lookups on connecting clients. The
14173 @code{double} setting causes @code{cupsd} to verify that the hostname
14174 resolved from the address matches one of the addresses returned for that
14175 hostname. Double lookups also prevent clients with unregistered
14176 addresses from connecting to your server. Only set this option to
14177 @code{#t} or @code{double} if absolutely required.
14179 Defaults to @samp{#f}.
14182 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
14183 Specifies the number of seconds to wait before killing the filters and
14184 backend associated with a canceled or held job.
14186 Defaults to @samp{30}.
14189 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
14190 Specifies the interval between retries of jobs in seconds. This is
14191 typically used for fax queues but can also be used with normal print
14192 queues whose error policy is @code{retry-job} or
14193 @code{retry-current-job}.
14195 Defaults to @samp{30}.
14198 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
14199 Specifies the number of retries that are done for jobs. This is
14200 typically used for fax queues but can also be used with normal print
14201 queues whose error policy is @code{retry-job} or
14202 @code{retry-current-job}.
14204 Defaults to @samp{5}.
14207 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
14208 Specifies whether to support HTTP keep-alive connections.
14210 Defaults to @samp{#t}.
14213 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
14214 Specifies how long an idle client connection remains open, in seconds.
14216 Defaults to @samp{30}.
14219 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
14220 Specifies the maximum size of print files, IPP requests, and HTML form
14221 data. A limit of 0 disables the limit check.
14223 Defaults to @samp{0}.
14226 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
14227 Listens on the specified interfaces for connections. Valid values are
14228 of the form @var{address}:@var{port}, where @var{address} is either an
14229 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
14230 indicate all addresses. Values can also be file names of local UNIX
14231 domain sockets. The Listen directive is similar to the Port directive
14232 but allows you to restrict access to specific interfaces or networks.
14235 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
14236 Specifies the number of pending connections that will be allowed. This
14237 normally only affects very busy servers that have reached the MaxClients
14238 limit, but can also be triggered by large numbers of simultaneous
14239 connections. When the limit is reached, the operating system will
14240 refuse additional connections until the scheduler can accept the pending
14243 Defaults to @samp{128}.
14246 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
14247 Specifies a set of additional access controls.
14249 Available @code{location-access-controls} fields are:
14251 @deftypevr {@code{location-access-controls} parameter} file-name path
14252 Specifies the URI path to which the access control applies.
14255 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
14256 Access controls for all access to this path, in the same format as the
14257 @code{access-controls} of @code{operation-access-control}.
14259 Defaults to @samp{()}.
14262 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
14263 Access controls for method-specific access to this path.
14265 Defaults to @samp{()}.
14267 Available @code{method-access-controls} fields are:
14269 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
14270 If @code{#t}, apply access controls to all methods except the listed
14271 methods. Otherwise apply to only the listed methods.
14273 Defaults to @samp{#f}.
14276 @deftypevr {@code{method-access-controls} parameter} method-list methods
14277 Methods to which this access control applies.
14279 Defaults to @samp{()}.
14282 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
14283 Access control directives, as a list of strings. Each string should be
14284 one directive, such as "Order allow,deny".
14286 Defaults to @samp{()}.
14291 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
14292 Specifies the number of debugging messages that are retained for logging
14293 if an error occurs in a print job. Debug messages are logged regardless
14294 of the LogLevel setting.
14296 Defaults to @samp{100}.
14299 @deftypevr {@code{cups-configuration} parameter} log-level log-level
14300 Specifies the level of logging for the ErrorLog file. The value
14301 @code{none} stops all logging while @code{debug2} logs everything.
14303 Defaults to @samp{info}.
14306 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
14307 Specifies the format of the date and time in the log files. The value
14308 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
14310 Defaults to @samp{standard}.
14313 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
14314 Specifies the maximum number of simultaneous clients that are allowed by
14317 Defaults to @samp{100}.
14320 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
14321 Specifies the maximum number of simultaneous clients that are allowed
14322 from a single address.
14324 Defaults to @samp{100}.
14327 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
14328 Specifies the maximum number of copies that a user can print of each
14331 Defaults to @samp{9999}.
14334 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
14335 Specifies the maximum time a job may remain in the @code{indefinite}
14336 hold state before it is canceled. A value of 0 disables cancellation of
14339 Defaults to @samp{0}.
14342 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
14343 Specifies the maximum number of simultaneous jobs that are allowed. Set
14344 to 0 to allow an unlimited number of jobs.
14346 Defaults to @samp{500}.
14349 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
14350 Specifies the maximum number of simultaneous jobs that are allowed per
14351 printer. A value of 0 allows up to MaxJobs jobs per printer.
14353 Defaults to @samp{0}.
14356 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
14357 Specifies the maximum number of simultaneous jobs that are allowed per
14358 user. A value of 0 allows up to MaxJobs jobs per user.
14360 Defaults to @samp{0}.
14363 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
14364 Specifies the maximum time a job may take to print before it is
14365 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
14367 Defaults to @samp{10800}.
14370 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
14371 Specifies the maximum size of the log files before they are rotated, in
14372 bytes. The value 0 disables log rotation.
14374 Defaults to @samp{1048576}.
14377 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
14378 Specifies the maximum amount of time to allow between files in a
14379 multiple file print job, in seconds.
14381 Defaults to @samp{300}.
14384 @deftypevr {@code{cups-configuration} parameter} string page-log-format
14385 Specifies the format of PageLog lines. Sequences beginning with percent
14386 (@samp{%}) characters are replaced with the corresponding information,
14387 while all other characters are copied literally. The following percent
14388 sequences are recognized:
14392 insert a single percent character
14395 insert the value of the specified IPP attribute
14398 insert the number of copies for the current page
14401 insert the current page number
14404 insert the current date and time in common log format
14410 insert the printer name
14413 insert the username
14416 A value of the empty string disables page logging. The string @code{%p
14417 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
14418 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
14421 Defaults to @samp{""}.
14424 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
14425 Passes the specified environment variable(s) to child processes; a list
14428 Defaults to @samp{()}.
14431 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
14432 Specifies named access control policies.
14434 Available @code{policy-configuration} fields are:
14436 @deftypevr {@code{policy-configuration} parameter} string name
14437 Name of the policy.
14440 @deftypevr {@code{policy-configuration} parameter} string job-private-access
14441 Specifies an access list for a job's private values. @code{@@ACL} maps
14442 to the printer's requesting-user-name-allowed or
14443 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14444 owner. @code{@@SYSTEM} maps to the groups listed for the
14445 @code{system-group} field of the @code{files-config} configuration,
14446 which is reified into the @code{cups-files.conf(5)} file. Other
14447 possible elements of the access list include specific user names, and
14448 @code{@@@var{group}} to indicate members of a specific group. The
14449 access list may also be simply @code{all} or @code{default}.
14451 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14454 @deftypevr {@code{policy-configuration} parameter} string job-private-values
14455 Specifies the list of job values to make private, or @code{all},
14456 @code{default}, or @code{none}.
14458 Defaults to @samp{"job-name job-originating-host-name
14459 job-originating-user-name phone"}.
14462 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
14463 Specifies an access list for a subscription's private values.
14464 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
14465 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14466 owner. @code{@@SYSTEM} maps to the groups listed for the
14467 @code{system-group} field of the @code{files-config} configuration,
14468 which is reified into the @code{cups-files.conf(5)} file. Other
14469 possible elements of the access list include specific user names, and
14470 @code{@@@var{group}} to indicate members of a specific group. The
14471 access list may also be simply @code{all} or @code{default}.
14473 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14476 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
14477 Specifies the list of job values to make private, or @code{all},
14478 @code{default}, or @code{none}.
14480 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
14481 notify-subscriber-user-name notify-user-data"}.
14484 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
14485 Access control by IPP operation.
14487 Defaults to @samp{()}.
14491 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
14492 Specifies whether job files (documents) are preserved after a job is
14493 printed. If a numeric value is specified, job files are preserved for
14494 the indicated number of seconds after printing. Otherwise a boolean
14495 value applies indefinitely.
14497 Defaults to @samp{86400}.
14500 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
14501 Specifies whether the job history is preserved after a job is printed.
14502 If a numeric value is specified, the job history is preserved for the
14503 indicated number of seconds after printing. If @code{#t}, the job
14504 history is preserved until the MaxJobs limit is reached.
14506 Defaults to @samp{#t}.
14509 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
14510 Specifies the amount of time to wait for job completion before
14511 restarting the scheduler.
14513 Defaults to @samp{30}.
14516 @deftypevr {@code{cups-configuration} parameter} string rip-cache
14517 Specifies the maximum amount of memory to use when converting documents
14518 into bitmaps for a printer.
14520 Defaults to @samp{"128m"}.
14523 @deftypevr {@code{cups-configuration} parameter} string server-admin
14524 Specifies the email address of the server administrator.
14526 Defaults to @samp{"root@@localhost.localdomain"}.
14529 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
14530 The ServerAlias directive is used for HTTP Host header validation when
14531 clients connect to the scheduler from external interfaces. Using the
14532 special name @code{*} can expose your system to known browser-based DNS
14533 rebinding attacks, even when accessing sites through a firewall. If the
14534 auto-discovery of alternate names does not work, we recommend listing
14535 each alternate name with a ServerAlias directive instead of using
14538 Defaults to @samp{*}.
14541 @deftypevr {@code{cups-configuration} parameter} string server-name
14542 Specifies the fully-qualified host name of the server.
14544 Defaults to @samp{"localhost"}.
14547 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
14548 Specifies what information is included in the Server header of HTTP
14549 responses. @code{None} disables the Server header. @code{ProductOnly}
14550 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
14551 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
14552 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
14553 the output of the @code{uname} command. @code{Full} reports @code{CUPS
14554 2.0.0 (@var{uname}) IPP/2.0}.
14556 Defaults to @samp{Minimal}.
14559 @deftypevr {@code{cups-configuration} parameter} string set-env
14560 Set the specified environment variable to be passed to child processes.
14562 Defaults to @samp{"variable value"}.
14565 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
14566 Listens on the specified interfaces for encrypted connections. Valid
14567 values are of the form @var{address}:@var{port}, where @var{address} is
14568 either an IPv6 address enclosed in brackets, an IPv4 address, or
14569 @code{*} to indicate all addresses.
14571 Defaults to @samp{()}.
14574 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
14575 Sets encryption options. By default, CUPS only supports encryption
14576 using TLS v1.0 or higher using known secure cipher suites. The
14577 @code{AllowRC4} option enables the 128-bit RC4 cipher suites, which are
14578 required for some older clients that do not implement newer ones. The
14579 @code{AllowSSL3} option enables SSL v3.0, which is required for some
14580 older clients that do not support TLS v1.0.
14582 Defaults to @samp{()}.
14585 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
14586 Specifies whether the scheduler requires clients to strictly adhere to
14587 the IPP specifications.
14589 Defaults to @samp{#f}.
14592 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
14593 Specifies the HTTP request timeout, in seconds.
14595 Defaults to @samp{300}.
14599 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
14600 Specifies whether the web interface is enabled.
14602 Defaults to @samp{#f}.
14605 At this point you're probably thinking ``oh dear, Guix manual, I like
14606 you but you can stop already with the configuration options''. Indeed.
14607 However, one more point: it could be that you have an existing
14608 @code{cupsd.conf} that you want to use. In that case, you can pass an
14609 @code{opaque-cups-configuration} as the configuration of a
14610 @code{cups-service-type}.
14612 Available @code{opaque-cups-configuration} fields are:
14614 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
14618 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
14619 The contents of the @code{cupsd.conf}, as a string.
14622 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
14623 The contents of the @code{cups-files.conf} file, as a string.
14626 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
14627 strings of the same name, you could instantiate a CUPS service like
14631 (service cups-service-type
14632 (opaque-cups-configuration
14633 (cupsd.conf cupsd.conf)
14634 (cups-files.conf cups-files.conf)))
14638 @node Desktop Services
14639 @subsection Desktop Services
14641 The @code{(gnu services desktop)} module provides services that are
14642 usually useful in the context of a ``desktop'' setup---that is, on a
14643 machine running a graphical display server, possibly with graphical user
14644 interfaces, etc. It also defines services that provide specific desktop
14645 environments like GNOME, Xfce or MATE.
14647 To simplify things, the module defines a variable containing the set of
14648 services that users typically expect on a machine with a graphical
14649 environment and networking:
14651 @defvr {Scheme Variable} %desktop-services
14652 This is a list of services that builds upon @var{%base-services} and
14653 adds or adjusts services for a typical ``desktop'' setup.
14655 In particular, it adds a graphical login manager (@pxref{X Window,
14656 @code{gdm-service-type}}), screen lockers, a network management tool
14657 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
14658 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
14659 energy and color management services, the @code{elogind} login and seat
14660 manager, the Polkit privilege service, the GeoClue location service, the
14661 AccountsService daemon that allows authorized users change system passwords,
14662 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
14663 name service switch service configured to be able to use @code{nss-mdns}
14664 (@pxref{Name Service Switch, mDNS}).
14667 The @var{%desktop-services} variable can be used as the @code{services}
14668 field of an @code{operating-system} declaration (@pxref{operating-system
14669 Reference, @code{services}}).
14671 Additionally, the @code{gnome-desktop-service-type},
14672 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
14673 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
14674 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
14675 services like the backlight adjustment helpers and the power management
14676 utilities are added to the system, extending @code{polkit} and @code{dbus}
14677 appropriately, allowing GNOME to operate with elevated privileges on a
14678 limited number of special-purpose system interfaces. Additionally,
14679 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
14680 metapackage to the system profile. Likewise, adding the Xfce service
14681 not only adds the @code{xfce} metapackage to the system profile, but it
14682 also gives the Thunar file manager the ability to open a ``root-mode''
14683 file management window, if the user authenticates using the
14684 administrator's password via the standard polkit graphical interface.
14685 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
14686 appropriately, allowing MATE to operate with elevated privileges on a
14687 limited number of special-purpose system interfaces. Additionally,
14688 adding a service of type @code{mate-desktop-service-type} adds the MATE
14689 metapackage to the system profile. ``Adding Enlightenment'' means that
14690 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
14691 are set as setuid, allowing Enlightenment's screen locker and other
14692 functionality to work as expetected.
14694 The desktop environments in Guix use the Xorg display server by
14695 default. If you'd like to use the newer display server protocol
14696 called Wayland, you need to use the @code{sddm-service} instead of
14697 GDM as the graphical login manager. You should then
14698 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
14699 also try starting GNOME on Wayland manually from a TTY with the
14700 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
14701 gnome-session``. Currently only GNOME has support for Wayland.
14703 @defvr {Scheme Variable} gnome-desktop-service-type
14704 This is the type of the service that adds the @uref{https://www.gnome.org,
14705 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
14706 object (see below.)
14708 This service adds the @code{gnome} package to the system profile, and extends
14709 polkit with the actions from @code{gnome-settings-daemon}.
14712 @deftp {Data Type} gnome-desktop-configuration
14713 Configuration record for the GNOME desktop environment.
14716 @item @code{gnome} (default: @code{gnome})
14717 The GNOME package to use.
14721 @defvr {Scheme Variable} xfce-desktop-service-type
14722 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
14723 desktop environment. Its value is an @code{xfce-desktop-configuration} object
14726 This service adds the @code{xfce} package to the system profile, and
14727 extends polkit with the ability for @code{thunar} to manipulate the file
14728 system as root from within a user session, after the user has authenticated
14729 with the administrator's password.
14732 @deftp {Data Type} xfce-desktop-configuration
14733 Configuration record for the Xfce desktop environment.
14736 @item @code{xfce} (default: @code{xfce})
14737 The Xfce package to use.
14741 @deffn {Scheme Variable} mate-desktop-service-type
14742 This is the type of the service that runs the @uref{https://mate-desktop.org/,
14743 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
14744 object (see below.)
14746 This service adds the @code{mate} package to the system
14747 profile, and extends polkit with the actions from
14748 @code{mate-settings-daemon}.
14751 @deftp {Data Type} mate-desktop-configuration
14752 Configuration record for the MATE desktop environment.
14755 @item @code{mate} (default: @code{mate})
14756 The MATE package to use.
14760 @deffn {Scheme Variable} enlightenment-desktop-service-type
14761 Return a service that adds the @code{enlightenment} package to the system
14762 profile, and extends dbus with actions from @code{efl}.
14765 @deftp {Data Type} enlightenment-desktop-service-configuration
14767 @item @code{enlightenment} (default: @code{enlightenment})
14768 The enlightenment package to use.
14772 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
14773 the default @code{%desktop-services} variable doesn't include any of
14774 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
14775 @code{%desktop-services} in the @code{services} field of your
14776 @code{operating-system}:
14779 (use-modules (gnu))
14780 (use-service-modules desktop)
14783 ;; cons* adds items to the list given as its last argument.
14784 (services (cons* (service gnome-desktop-service-type)
14785 (service xfce-desktop-service)
14786 %desktop-services))
14790 These desktop environments will then be available as options in the
14791 graphical login window.
14793 The actual service definitions included in @code{%desktop-services} and
14794 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
14795 are described below.
14797 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
14798 Return a service that runs the ``system bus'', using @var{dbus}, with
14799 support for @var{services}.
14801 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
14802 facility. Its system bus is used to allow system services to communicate
14803 and to be notified of system-wide events.
14805 @var{services} must be a list of packages that provide an
14806 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
14807 and policy files. For example, to allow avahi-daemon to use the system bus,
14808 @var{services} must be equal to @code{(list avahi)}.
14811 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
14812 Return a service that runs the @code{elogind} login and
14813 seat management daemon. @uref{https://github.com/elogind/elogind,
14814 Elogind} exposes a D-Bus interface that can be used to know which users
14815 are logged in, know what kind of sessions they have open, suspend the
14816 system, inhibit system suspend, reboot the system, and other tasks.
14818 Elogind handles most system-level power events for a computer, for
14819 example suspending the system when a lid is closed, or shutting it down
14820 when the power button is pressed.
14822 The @var{config} keyword argument specifies the configuration for
14823 elogind, and should be the result of an @code{(elogind-configuration
14824 (@var{parameter} @var{value})...)} invocation. Available parameters and
14825 their default values are:
14828 @item kill-user-processes?
14830 @item kill-only-users
14832 @item kill-exclude-users
14834 @item inhibit-delay-max-seconds
14836 @item handle-power-key
14838 @item handle-suspend-key
14840 @item handle-hibernate-key
14842 @item handle-lid-switch
14844 @item handle-lid-switch-docked
14846 @item power-key-ignore-inhibited?
14848 @item suspend-key-ignore-inhibited?
14850 @item hibernate-key-ignore-inhibited?
14852 @item lid-switch-ignore-inhibited?
14854 @item holdoff-timeout-seconds
14858 @item idle-action-seconds
14860 @item runtime-directory-size-percent
14862 @item runtime-directory-size
14866 @item suspend-state
14867 @code{("mem" "standby" "freeze")}
14870 @item hibernate-state
14872 @item hibernate-mode
14873 @code{("platform" "shutdown")}
14874 @item hybrid-sleep-state
14876 @item hybrid-sleep-mode
14877 @code{("suspend" "platform" "shutdown")}
14881 @deffn {Scheme Procedure} accountsservice-service @
14882 [#:accountsservice @var{accountsservice}]
14883 Return a service that runs AccountsService, a system service that can
14884 list available accounts, change their passwords, and so on.
14885 AccountsService integrates with PolicyKit to enable unprivileged users
14886 to acquire the capability to modify their system configuration.
14887 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
14888 accountsservice web site} for more information.
14890 The @var{accountsservice} keyword argument is the @code{accountsservice}
14891 package to expose as a service.
14894 @deffn {Scheme Procedure} polkit-service @
14895 [#:polkit @var{polkit}]
14896 Return a service that runs the
14897 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
14898 management service}, which allows system administrators to grant access to
14899 privileged operations in a structured way. By querying the Polkit service, a
14900 privileged system component can know when it should grant additional
14901 capabilities to ordinary users. For example, an ordinary user can be granted
14902 the capability to suspend the system if the user is logged in locally.
14905 @defvr {Scheme Variable} upower-service-type
14906 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
14907 system-wide monitor for power consumption and battery levels, with the given
14908 configuration settings.
14910 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
14911 notably used by GNOME.
14914 @deftp {Data Type} upower-configuration
14915 Data type representation the configuration for UPower.
14919 @item @code{upower} (default: @var{upower})
14920 Package to use for @code{upower}.
14922 @item @code{watts-up-pro?} (default: @code{#f})
14923 Enable the Watts Up Pro device.
14925 @item @code{poll-batteries?} (default: @code{#t})
14926 Enable polling the kernel for battery level changes.
14928 @item @code{ignore-lid?} (default: @code{#f})
14929 Ignore the lid state, this can be useful if it's incorrect on a device.
14931 @item @code{use-percentage-for-policy?} (default: @code{#f})
14932 Whether battery percentage based policy should be used. The default is to use
14933 the time left, change to @code{#t} to use the percentage.
14935 @item @code{percentage-low} (default: @code{10})
14936 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
14937 at which the battery is considered low.
14939 @item @code{percentage-critical} (default: @code{3})
14940 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
14941 at which the battery is considered critical.
14943 @item @code{percentage-action} (default: @code{2})
14944 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
14945 at which action will be taken.
14947 @item @code{time-low} (default: @code{1200})
14948 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
14949 seconds at which the battery is considered low.
14951 @item @code{time-critical} (default: @code{300})
14952 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
14953 seconds at which the battery is considered critical.
14955 @item @code{time-action} (default: @code{120})
14956 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
14957 seconds at which action will be taken.
14959 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
14960 The action taken when @code{percentage-action} or @code{time-action} is
14961 reached (depending on the configuration of @code{use-percentage-for-policy?}).
14963 Possible values are:
14973 @code{'hybrid-sleep}.
14979 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
14980 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
14981 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
14982 notifications and ways to mount/unmount disks. Programs that talk to UDisks
14983 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
14986 @deffn {Scheme Procedure} colord-service [#:colord @var{colord}]
14987 Return a service that runs @command{colord}, a system service with a D-Bus
14988 interface to manage the color profiles of input and output devices such as
14989 screens and scanners. It is notably used by the GNOME Color Manager graphical
14990 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
14991 site} for more information.
14994 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
14995 Return a configuration allowing an application to access GeoClue
14996 location data. @var{name} is the Desktop ID of the application, without
14997 the @code{.desktop} part. If @var{allowed?} is true, the application
14998 will have access to location information by default. The boolean
14999 @var{system?} value indicates whether an application is a system component
15000 or not. Finally @var{users} is a list of UIDs of all users for which
15001 this application is allowed location info access. An empty users list
15002 means that all users are allowed.
15005 @defvr {Scheme Variable} %standard-geoclue-applications
15006 The standard list of well-known GeoClue application configurations,
15007 granting authority to the GNOME date-and-time utility to ask for the
15008 current location in order to set the time zone, and allowing the
15009 IceCat and Epiphany web browsers to request location information.
15010 IceCat and Epiphany both query the user before allowing a web page to
15011 know the user's location.
15014 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
15015 [#:whitelist '()] @
15016 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
15017 [#:submit-data? #f]
15018 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
15019 [#:submission-nick "geoclue"] @
15020 [#:applications %standard-geoclue-applications]
15021 Return a service that runs the GeoClue location service. This service
15022 provides a D-Bus interface to allow applications to request access to a
15023 user's physical location, and optionally to add information to online
15024 location databases. See
15025 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
15026 web site} for more information.
15029 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
15030 [@w{#:auto-enable? #f}]
15031 Return a service that runs the @command{bluetoothd} daemon, which
15032 manages all the Bluetooth devices and provides a number of D-Bus
15033 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
15034 powered automatically at boot, which can be useful when using a
15035 bluetooth keyboard or mouse.
15037 Users need to be in the @code{lp} group to access the D-Bus service.
15040 @node Sound Services
15041 @subsection Sound Services
15043 @cindex sound support
15045 @cindex PulseAudio, sound support
15047 The @code{(gnu services sound)} module provides a service to configure the
15048 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
15049 preferred ALSA output driver.
15051 @deffn {Scheme Variable} alsa-service-type
15052 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
15053 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
15054 configuration file. The value for this type is a @command{alsa-configuration}
15055 record as in this example:
15058 (service alsa-service-type)
15061 See below for details about @code{alsa-configuration}.
15064 @deftp {Data Type} alsa-configuration
15065 Data type representing the configuration for @code{alsa-service}.
15068 @item @code{alsa-plugins} (default: @var{alsa-plugins})
15069 @code{alsa-plugins} package to use.
15071 @item @code{pulseaudio?} (default: @var{#t})
15072 Whether ALSA applications should transparently be made to use the
15073 @uref{http://www.pulseaudio.org/, PulseAudio} sound server.
15075 Using PulseAudio allows you to run several sound-producing applications
15076 at the same time and to individual control them @i{via}
15077 @command{pavucontrol}, among other things.
15079 @item @code{extra-options} (default: @var{""})
15080 String to append to the @file{/etc/asound.conf} file.
15085 Individual users who want to override the system configuration of ALSA can do
15086 it with the @file{~/.asoundrc} file:
15089 # In guix, we have to specify the absolute path for plugins.
15091 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
15094 # Routing ALSA to jack:
15095 # <http://jackaudio.org/faq/routing_alsa.html>.
15099 0 system:playback_1
15100 1 system:playback_2
15117 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
15121 @node Database Services
15122 @subsection Database Services
15126 The @code{(gnu services databases)} module provides the following services.
15128 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
15129 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
15130 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
15131 Return a service that runs @var{postgresql}, the PostgreSQL database
15134 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
15135 creates a database cluster with @var{locale} as the default
15136 locale, stored in @var{data-directory}. It then listens on @var{port}.
15138 @cindex postgresql extension-packages
15139 Additional extensions are loaded from packages listed in
15140 @var{extension-packages}. Extensions are available at runtime. For instance,
15141 to create a geographic database using the @code{postgis} extension, a user can
15142 configure the postgresql-service as in this example:
15146 (use-package-modules databases geo)
15150 ;; postgresql is required to run `psql' but postgis is not required for
15151 ;; proper operation.
15152 (packages (cons* postgresql %base-packages))
15155 (postgresql-service #:extension-packages (list postgis))
15159 Then the extension becomes visible and you can initialise an empty geographic
15160 database in this way:
15164 > create database postgistest;
15165 > \connect postgistest;
15166 > create extension postgis;
15167 > create extension postgis_topology;
15170 There is no need to add this field for contrib extensions such as hstore or
15171 dblink as they are already loadable by postgresql. This field is only
15172 required to add extensions provided by other packages.
15175 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
15176 Return a service that runs @command{mysqld}, the MySQL or MariaDB
15179 The optional @var{config} argument specifies the configuration for
15180 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
15183 @deftp {Data Type} mysql-configuration
15184 Data type representing the configuration of @var{mysql-service}.
15187 @item @code{mysql} (default: @var{mariadb})
15188 Package object of the MySQL database server, can be either @var{mariadb}
15191 For MySQL, a temporary root password will be displayed at activation time.
15192 For MariaDB, the root password is empty.
15194 @item @code{port} (default: @code{3306})
15195 TCP port on which the database server listens for incoming connections.
15199 @defvr {Scheme Variable} memcached-service-type
15200 This is the service type for the @uref{https://memcached.org/,
15201 Memcached} service, which provides a distributed in memory cache. The
15202 value for the service type is a @code{memcached-configuration} object.
15206 (service memcached-service-type)
15209 @deftp {Data Type} memcached-configuration
15210 Data type representing the configuration of memcached.
15213 @item @code{memcached} (default: @code{memcached})
15214 The Memcached package to use.
15216 @item @code{interfaces} (default: @code{'("0.0.0.0")})
15217 Network interfaces on which to listen.
15219 @item @code{tcp-port} (default: @code{11211})
15220 Port on which to accept connections on,
15222 @item @code{udp-port} (default: @code{11211})
15223 Port on which to accept UDP connections on, a value of 0 will disable
15224 listening on a UDP socket.
15226 @item @code{additional-options} (default: @code{'()})
15227 Additional command line options to pass to @code{memcached}.
15231 @defvr {Scheme Variable} mongodb-service-type
15232 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
15233 The value for the service type is a @code{mongodb-configuration} object.
15237 (service mongodb-service-type)
15240 @deftp {Data Type} mongodb-configuration
15241 Data type representing the configuration of mongodb.
15244 @item @code{mongodb} (default: @code{mongodb})
15245 The MongoDB package to use.
15247 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
15248 The configuration file for MongoDB.
15250 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
15251 This value is used to create the directory, so that it exists and is
15252 owned by the mongodb user. It should match the data-directory which
15253 MongoDB is configured to use through the configuration file.
15257 @defvr {Scheme Variable} redis-service-type
15258 This is the service type for the @uref{https://redis.io/, Redis}
15259 key/value store, whose value is a @code{redis-configuration} object.
15262 @deftp {Data Type} redis-configuration
15263 Data type representing the configuration of redis.
15266 @item @code{redis} (default: @code{redis})
15267 The Redis package to use.
15269 @item @code{bind} (default: @code{"127.0.0.1"})
15270 Network interface on which to listen.
15272 @item @code{port} (default: @code{6379})
15273 Port on which to accept connections on, a value of 0 will disable
15274 listening on a TCP socket.
15276 @item @code{working-directory} (default: @code{"/var/lib/redis"})
15277 Directory in which to store the database and related files.
15281 @node Mail Services
15282 @subsection Mail Services
15286 The @code{(gnu services mail)} module provides Guix service definitions
15287 for email services: IMAP, POP3, and LMTP servers, as well as mail
15288 transport agents (MTAs). Lots of acronyms! These services are detailed
15289 in the subsections below.
15291 @subsubheading Dovecot Service
15293 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
15294 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
15297 By default, Dovecot does not need much configuration; the default
15298 configuration object created by @code{(dovecot-configuration)} will
15299 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
15300 certificate will be generated for TLS-protected connections, though
15301 Dovecot will also listen on cleartext ports by default. There are a
15302 number of options, though, which mail administrators might need to change,
15303 and as is the case with other services, Guix allows the system
15304 administrator to specify these parameters via a uniform Scheme interface.
15306 For example, to specify that mail is located at @code{maildir~/.mail},
15307 one would instantiate the Dovecot service like this:
15310 (dovecot-service #:config
15311 (dovecot-configuration
15312 (mail-location "maildir:~/.mail")))
15315 The available configuration parameters follow. Each parameter
15316 definition is preceded by its type; for example, @samp{string-list foo}
15317 indicates that the @code{foo} parameter should be specified as a list of
15318 strings. There is also a way to specify the configuration as a string,
15319 if you have an old @code{dovecot.conf} file that you want to port over
15320 from some other system; see the end for more details.
15322 @c The following documentation was initially generated by
15323 @c (generate-documentation) in (gnu services mail). Manually maintained
15324 @c documentation is better, so we shouldn't hesitate to edit below as
15325 @c needed. However if the change you want to make to this documentation
15326 @c can be done in an automated way, it's probably easier to change
15327 @c (generate-documentation) than to make it below and have to deal with
15328 @c the churn as dovecot updates.
15330 Available @code{dovecot-configuration} fields are:
15332 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
15333 The dovecot package.
15336 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
15337 A list of IPs or hosts where to listen for connections. @samp{*}
15338 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
15339 interfaces. If you want to specify non-default ports or anything more
15340 complex, customize the address and port fields of the
15341 @samp{inet-listener} of the specific services you are interested in.
15344 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
15345 List of protocols we want to serve. Available protocols include
15346 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
15348 Available @code{protocol-configuration} fields are:
15350 @deftypevr {@code{protocol-configuration} parameter} string name
15351 The name of the protocol.
15354 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
15355 UNIX socket path to the master authentication server to find users.
15356 This is used by imap (for shared users) and lda.
15357 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
15360 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
15361 Space separated list of plugins to load.
15364 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
15365 Maximum number of IMAP connections allowed for a user from each IP
15366 address. NOTE: The username is compared case-sensitively.
15367 Defaults to @samp{10}.
15372 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
15373 List of services to enable. Available services include @samp{imap},
15374 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
15377 Available @code{service-configuration} fields are:
15379 @deftypevr {@code{service-configuration} parameter} string kind
15380 The service kind. Valid values include @code{director},
15381 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
15382 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
15383 @code{tcpwrap}, @code{quota-warning}, or anything else.
15386 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
15387 Listeners for the service. A listener is either a
15388 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
15389 an @code{inet-listener-configuration}.
15390 Defaults to @samp{()}.
15392 Available @code{unix-listener-configuration} fields are:
15394 @deftypevr {@code{unix-listener-configuration} parameter} string path
15395 Path to the file, relative to @code{base-dir} field. This is also used as
15399 @deftypevr {@code{unix-listener-configuration} parameter} string mode
15400 The access mode for the socket.
15401 Defaults to @samp{"0600"}.
15404 @deftypevr {@code{unix-listener-configuration} parameter} string user
15405 The user to own the socket.
15406 Defaults to @samp{""}.
15409 @deftypevr {@code{unix-listener-configuration} parameter} string group
15410 The group to own the socket.
15411 Defaults to @samp{""}.
15415 Available @code{fifo-listener-configuration} fields are:
15417 @deftypevr {@code{fifo-listener-configuration} parameter} string path
15418 Path to the file, relative to @code{base-dir} field. This is also used as
15422 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
15423 The access mode for the socket.
15424 Defaults to @samp{"0600"}.
15427 @deftypevr {@code{fifo-listener-configuration} parameter} string user
15428 The user to own the socket.
15429 Defaults to @samp{""}.
15432 @deftypevr {@code{fifo-listener-configuration} parameter} string group
15433 The group to own the socket.
15434 Defaults to @samp{""}.
15438 Available @code{inet-listener-configuration} fields are:
15440 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
15441 The protocol to listen for.
15444 @deftypevr {@code{inet-listener-configuration} parameter} string address
15445 The address on which to listen, or empty for all addresses.
15446 Defaults to @samp{""}.
15449 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
15450 The port on which to listen.
15453 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
15454 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
15456 Defaults to @samp{#t}.
15461 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
15462 Maximum number of simultaneous client connections per process. Once
15463 this number of connections is received, the next incoming connection
15464 will prompt Dovecot to spawn another process. If set to 0,
15465 @code{default-client-limit} is used instead.
15467 Defaults to @samp{0}.
15471 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
15472 Number of connections to handle before starting a new process.
15473 Typically the only useful values are 0 (unlimited) or 1. 1 is more
15474 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
15475 Defaults to @samp{1}.
15479 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
15480 Maximum number of processes that can exist for this service. If set to
15481 0, @code{default-process-limit} is used instead.
15483 Defaults to @samp{0}.
15487 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
15488 Number of processes to always keep waiting for more connections.
15489 Defaults to @samp{0}.
15492 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
15493 If you set @samp{service-count 0}, you probably need to grow
15495 Defaults to @samp{256000000}.
15500 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
15501 Dict configuration, as created by the @code{dict-configuration}
15504 Available @code{dict-configuration} fields are:
15506 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
15507 A list of key-value pairs that this dict should hold.
15508 Defaults to @samp{()}.
15513 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
15514 A list of passdb configurations, each one created by the
15515 @code{passdb-configuration} constructor.
15517 Available @code{passdb-configuration} fields are:
15519 @deftypevr {@code{passdb-configuration} parameter} string driver
15520 The driver that the passdb should use. Valid values include
15521 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
15523 Defaults to @samp{"pam"}.
15526 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
15527 Space separated list of arguments to the passdb driver.
15528 Defaults to @samp{""}.
15533 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
15534 List of userdb configurations, each one created by the
15535 @code{userdb-configuration} constructor.
15537 Available @code{userdb-configuration} fields are:
15539 @deftypevr {@code{userdb-configuration} parameter} string driver
15540 The driver that the userdb should use. Valid values include
15541 @samp{passwd} and @samp{static}.
15542 Defaults to @samp{"passwd"}.
15545 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
15546 Space separated list of arguments to the userdb driver.
15547 Defaults to @samp{""}.
15550 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
15551 Override fields from passwd.
15552 Defaults to @samp{()}.
15557 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
15558 Plug-in configuration, created by the @code{plugin-configuration}
15562 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
15563 List of namespaces. Each item in the list is created by the
15564 @code{namespace-configuration} constructor.
15566 Available @code{namespace-configuration} fields are:
15568 @deftypevr {@code{namespace-configuration} parameter} string name
15569 Name for this namespace.
15572 @deftypevr {@code{namespace-configuration} parameter} string type
15573 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
15574 Defaults to @samp{"private"}.
15577 @deftypevr {@code{namespace-configuration} parameter} string separator
15578 Hierarchy separator to use. You should use the same separator for
15579 all namespaces or some clients get confused. @samp{/} is usually a good
15580 one. The default however depends on the underlying mail storage
15582 Defaults to @samp{""}.
15585 @deftypevr {@code{namespace-configuration} parameter} string prefix
15586 Prefix required to access this namespace. This needs to be
15587 different for all namespaces. For example @samp{Public/}.
15588 Defaults to @samp{""}.
15591 @deftypevr {@code{namespace-configuration} parameter} string location
15592 Physical location of the mailbox. This is in the same format as
15593 mail_location, which is also the default for it.
15594 Defaults to @samp{""}.
15597 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
15598 There can be only one INBOX, and this setting defines which
15600 Defaults to @samp{#f}.
15603 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
15604 If namespace is hidden, it's not advertised to clients via NAMESPACE
15605 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
15606 useful when converting from another server with different namespaces
15607 which you want to deprecate but still keep working. For example you can
15608 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
15610 Defaults to @samp{#f}.
15613 @deftypevr {@code{namespace-configuration} parameter} boolean list?
15614 Show the mailboxes under this namespace with the LIST command. This
15615 makes the namespace visible for clients that do not support the NAMESPACE
15616 extension. The special @code{children} value lists child mailboxes, but
15617 hides the namespace prefix.
15618 Defaults to @samp{#t}.
15621 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
15622 Namespace handles its own subscriptions. If set to @code{#f}, the
15623 parent namespace handles them. The empty prefix should always have this
15625 Defaults to @samp{#t}.
15628 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
15629 List of predefined mailboxes in this namespace.
15630 Defaults to @samp{()}.
15632 Available @code{mailbox-configuration} fields are:
15634 @deftypevr {@code{mailbox-configuration} parameter} string name
15635 Name for this mailbox.
15638 @deftypevr {@code{mailbox-configuration} parameter} string auto
15639 @samp{create} will automatically create this mailbox.
15640 @samp{subscribe} will both create and subscribe to the mailbox.
15641 Defaults to @samp{"no"}.
15644 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
15645 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
15646 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
15647 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
15648 Defaults to @samp{()}.
15655 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
15656 Base directory where to store runtime data.
15657 Defaults to @samp{"/var/run/dovecot/"}.
15660 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
15661 Greeting message for clients.
15662 Defaults to @samp{"Dovecot ready."}.
15665 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
15666 List of trusted network ranges. Connections from these IPs are
15667 allowed to override their IP addresses and ports (for logging and for
15668 authentication checks). @samp{disable-plaintext-auth} is also ignored
15669 for these networks. Typically you would specify your IMAP proxy servers
15671 Defaults to @samp{()}.
15674 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
15675 List of login access check sockets (e.g.@: tcpwrap).
15676 Defaults to @samp{()}.
15679 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
15680 Show more verbose process titles (in ps). Currently shows user name
15681 and IP address. Useful for seeing who is actually using the IMAP
15682 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
15684 Defaults to @samp{#f}.
15687 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
15688 Should all processes be killed when Dovecot master process shuts down.
15689 Setting this to @code{#f} means that Dovecot can be upgraded without
15690 forcing existing client connections to close (although that could also
15691 be a problem if the upgrade is e.g.@: due to a security fix).
15692 Defaults to @samp{#t}.
15695 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
15696 If non-zero, run mail commands via this many connections to doveadm
15697 server, instead of running them directly in the same process.
15698 Defaults to @samp{0}.
15701 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
15702 UNIX socket or host:port used for connecting to doveadm server.
15703 Defaults to @samp{"doveadm-server"}.
15706 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
15707 List of environment variables that are preserved on Dovecot startup
15708 and passed down to all of its child processes. You can also give
15709 key=value pairs to always set specific settings.
15712 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
15713 Disable LOGIN command and all other plaintext authentications unless
15714 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
15715 matches the local IP (i.e.@: you're connecting from the same computer),
15716 the connection is considered secure and plaintext authentication is
15717 allowed. See also ssl=required setting.
15718 Defaults to @samp{#t}.
15721 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
15722 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
15723 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
15724 for caching to be used.
15725 Defaults to @samp{0}.
15728 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
15729 Time to live for cached data. After TTL expires the cached record
15730 is no longer used, *except* if the main database lookup returns internal
15731 failure. We also try to handle password changes automatically: If
15732 user's previous authentication was successful, but this one wasn't, the
15733 cache isn't used. For now this works only with plaintext
15735 Defaults to @samp{"1 hour"}.
15738 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
15739 TTL for negative hits (user not found, password mismatch).
15740 0 disables caching them completely.
15741 Defaults to @samp{"1 hour"}.
15744 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
15745 List of realms for SASL authentication mechanisms that need them.
15746 You can leave it empty if you don't want to support multiple realms.
15747 Many clients simply use the first one listed here, so keep the default
15749 Defaults to @samp{()}.
15752 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
15753 Default realm/domain to use if none was specified. This is used for
15754 both SASL realms and appending @@domain to username in plaintext
15756 Defaults to @samp{""}.
15759 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
15760 List of allowed characters in username. If the user-given username
15761 contains a character not listed in here, the login automatically fails.
15762 This is just an extra check to make sure user can't exploit any
15763 potential quote escaping vulnerabilities with SQL/LDAP databases. If
15764 you want to allow all characters, set this value to empty.
15765 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
15768 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
15769 Username character translations before it's looked up from
15770 databases. The value contains series of from -> to characters. For
15771 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
15772 translated to @samp{@@}.
15773 Defaults to @samp{""}.
15776 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
15777 Username formatting before it's looked up from databases. You can
15778 use the standard variables here, e.g.@: %Lu would lowercase the username,
15779 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
15780 change the @samp{@@} into @samp{-AT-}. This translation is done after
15781 @samp{auth-username-translation} changes.
15782 Defaults to @samp{"%Lu"}.
15785 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
15786 If you want to allow master users to log in by specifying the master
15787 username within the normal username string (i.e.@: not using SASL
15788 mechanism's support for it), you can specify the separator character
15789 here. The format is then <username><separator><master username>.
15790 UW-IMAP uses @samp{*} as the separator, so that could be a good
15792 Defaults to @samp{""}.
15795 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
15796 Username to use for users logging in with ANONYMOUS SASL
15798 Defaults to @samp{"anonymous"}.
15801 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
15802 Maximum number of dovecot-auth worker processes. They're used to
15803 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
15804 They're automatically created and destroyed as needed.
15805 Defaults to @samp{30}.
15808 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
15809 Host name to use in GSSAPI principal names. The default is to use
15810 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
15811 allow all keytab entries.
15812 Defaults to @samp{""}.
15815 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
15816 Kerberos keytab to use for the GSSAPI mechanism. Will use the
15817 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
15818 need to change the auth service to run as root to be able to read this
15820 Defaults to @samp{""}.
15823 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
15824 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
15825 and @samp{ntlm-auth} helper.
15826 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
15827 Defaults to @samp{#f}.
15830 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
15831 Path for Samba's @samp{ntlm-auth} helper binary.
15832 Defaults to @samp{"/usr/bin/ntlm_auth"}.
15835 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
15836 Time to delay before replying to failed authentications.
15837 Defaults to @samp{"2 secs"}.
15840 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
15841 Require a valid SSL client certificate or the authentication
15843 Defaults to @samp{#f}.
15846 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
15847 Take the username from client's SSL certificate, using
15848 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
15850 Defaults to @samp{#f}.
15853 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
15854 List of wanted authentication mechanisms. Supported mechanisms are:
15855 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
15856 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
15857 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
15858 @samp{disable-plaintext-auth} setting.
15861 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
15862 List of IPs or hostnames to all director servers, including ourself.
15863 Ports can be specified as ip:port. The default port is the same as what
15864 director service's @samp{inet-listener} is using.
15865 Defaults to @samp{()}.
15868 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
15869 List of IPs or hostnames to all backend mail servers. Ranges are
15870 allowed too, like 10.0.0.10-10.0.0.30.
15871 Defaults to @samp{()}.
15874 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
15875 How long to redirect users to a specific server after it no longer
15876 has any connections.
15877 Defaults to @samp{"15 min"}.
15880 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
15881 How the username is translated before being hashed. Useful values
15882 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
15883 are shared within domain.
15884 Defaults to @samp{"%Lu"}.
15887 @deftypevr {@code{dovecot-configuration} parameter} string log-path
15888 Log file to use for error messages. @samp{syslog} logs to syslog,
15889 @samp{/dev/stderr} logs to stderr.
15890 Defaults to @samp{"syslog"}.
15893 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
15894 Log file to use for informational messages. Defaults to
15896 Defaults to @samp{""}.
15899 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
15900 Log file to use for debug messages. Defaults to
15901 @samp{info-log-path}.
15902 Defaults to @samp{""}.
15905 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
15906 Syslog facility to use if you're logging to syslog. Usually if you
15907 don't want to use @samp{mail}, you'll use local0..local7. Also other
15908 standard facilities are supported.
15909 Defaults to @samp{"mail"}.
15912 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
15913 Log unsuccessful authentication attempts and the reasons why they
15915 Defaults to @samp{#f}.
15918 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
15919 In case of password mismatches, log the attempted password. Valid
15920 values are no, plain and sha1. sha1 can be useful for detecting brute
15921 force password attempts vs. user simply trying the same password over
15922 and over again. You can also truncate the value to n chars by appending
15923 ":n" (e.g.@: sha1:6).
15924 Defaults to @samp{"no"}.
15927 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
15928 Even more verbose logging for debugging purposes. Shows for example
15930 Defaults to @samp{#f}.
15933 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
15934 In case of password mismatches, log the passwords and used scheme so
15935 the problem can be debugged. Enabling this also enables
15937 Defaults to @samp{#f}.
15940 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
15941 Enable mail process debugging. This can help you figure out why
15942 Dovecot isn't finding your mails.
15943 Defaults to @samp{#f}.
15946 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
15947 Show protocol level SSL errors.
15948 Defaults to @samp{#f}.
15951 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
15952 Prefix for each line written to log file. % codes are in
15953 strftime(3) format.
15954 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
15957 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
15958 List of elements we want to log. The elements which have a
15959 non-empty variable value are joined together to form a comma-separated
15963 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
15964 Login log format. %s contains @samp{login-log-format-elements}
15965 string, %$ contains the data we want to log.
15966 Defaults to @samp{"%$: %s"}.
15969 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
15970 Log prefix for mail processes. See doc/wiki/Variables.txt for list
15971 of possible variables you can use.
15972 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
15975 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
15976 Format to use for logging mail deliveries. You can use variables:
15979 Delivery status message (e.g.@: @samp{saved to INBOX})
15991 Defaults to @samp{"msgid=%m: %$"}.
15994 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
15995 Location for users' mailboxes. The default is empty, which means
15996 that Dovecot tries to find the mailboxes automatically. This won't work
15997 if the user doesn't yet have any mail, so you should explicitly tell
15998 Dovecot the full location.
16000 If you're using mbox, giving a path to the INBOX
16001 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
16002 where the other mailboxes are kept. This is called the "root mail
16003 directory", and it must be the first path given in the
16004 @samp{mail-location} setting.
16006 There are a few special variables you can use, eg.:
16012 user part in user@@domain, same as %u if there's no domain
16014 domain part in user@@domain, empty if there's no domain
16019 See doc/wiki/Variables.txt for full list. Some examples:
16021 @item maildir:~/Maildir
16022 @item mbox:~/mail:INBOX=/var/mail/%u
16023 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
16025 Defaults to @samp{""}.
16028 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
16029 System user and group used to access mails. If you use multiple,
16030 userdb can override these by returning uid or gid fields. You can use
16031 either numbers or names. <doc/wiki/UserIds.txt>.
16032 Defaults to @samp{""}.
16035 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
16037 Defaults to @samp{""}.
16040 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
16041 Group to enable temporarily for privileged operations. Currently
16042 this is used only with INBOX when either its initial creation or
16043 dotlocking fails. Typically this is set to "mail" to give access to
16045 Defaults to @samp{""}.
16048 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
16049 Grant access to these supplementary groups for mail processes.
16050 Typically these are used to set up access to shared mailboxes. Note
16051 that it may be dangerous to set these if users can create
16052 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
16053 could allow a user to delete others' mailboxes, or ln -s
16054 /secret/shared/box ~/mail/mybox would allow reading it).
16055 Defaults to @samp{""}.
16058 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
16059 Allow full file system access to clients. There's no access checks
16060 other than what the operating system does for the active UID/GID. It
16061 works with both maildir and mboxes, allowing you to prefix mailboxes
16062 names with e.g.@: /path/ or ~user/.
16063 Defaults to @samp{#f}.
16066 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
16067 Don't use mmap() at all. This is required if you store indexes to
16068 shared file systems (NFS or clustered file system).
16069 Defaults to @samp{#f}.
16072 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
16073 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
16074 supports @samp{O_EXCL} since version 3, so this should be safe to use
16075 nowadays by default.
16076 Defaults to @samp{#t}.
16079 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
16080 When to use fsync() or fdatasync() calls:
16083 Whenever necessary to avoid losing important data
16085 Useful with e.g.@: NFS when write()s are delayed
16087 Never use it (best performance, but crashes can lose data).
16089 Defaults to @samp{"optimized"}.
16092 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
16093 Mail storage exists in NFS. Set this to yes to make Dovecot flush
16094 NFS caches whenever needed. If you're using only a single mail server
16096 Defaults to @samp{#f}.
16099 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
16100 Mail index files also exist in NFS. Setting this to yes requires
16101 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
16102 Defaults to @samp{#f}.
16105 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
16106 Locking method for index files. Alternatives are fcntl, flock and
16107 dotlock. Dotlocking uses some tricks which may create more disk I/O
16108 than other locking methods. NFS users: flock doesn't work, remember to
16109 change @samp{mmap-disable}.
16110 Defaults to @samp{"fcntl"}.
16113 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
16114 Directory in which LDA/LMTP temporarily stores incoming mails >128
16116 Defaults to @samp{"/tmp"}.
16119 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
16120 Valid UID range for users. This is mostly to make sure that users can't
16121 log in as daemons or other system users. Note that denying root logins is
16122 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
16124 Defaults to @samp{500}.
16127 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
16129 Defaults to @samp{0}.
16132 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
16133 Valid GID range for users. Users having non-valid GID as primary group ID
16134 aren't allowed to log in. If user belongs to supplementary groups with
16135 non-valid GIDs, those groups are not set.
16136 Defaults to @samp{1}.
16139 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
16141 Defaults to @samp{0}.
16144 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
16145 Maximum allowed length for mail keyword name. It's only forced when
16146 trying to create new keywords.
16147 Defaults to @samp{50}.
16150 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
16151 List of directories under which chrooting is allowed for mail
16152 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
16153 too). This setting doesn't affect @samp{login-chroot}
16154 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
16155 "/./" in home dirs are ignored. WARNING: Never add directories here
16156 which local users can modify, that may lead to root exploit. Usually
16157 this should be done only if you don't allow shell access for users.
16158 <doc/wiki/Chrooting.txt>.
16159 Defaults to @samp{()}.
16162 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
16163 Default chroot directory for mail processes. This can be overridden
16164 for specific users in user database by giving /./ in user's home
16165 directory (e.g.@: /home/./user chroots into /home). Note that usually
16166 there is no real need to do chrooting, Dovecot doesn't allow users to
16167 access files outside their mail directory anyway. If your home
16168 directories are prefixed with the chroot directory, append "/."@: to
16169 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
16170 Defaults to @samp{""}.
16173 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
16174 UNIX socket path to master authentication server to find users.
16175 This is used by imap (for shared users) and lda.
16176 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16179 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
16180 Directory where to look up mail plugins.
16181 Defaults to @samp{"/usr/lib/dovecot"}.
16184 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
16185 List of plugins to load for all services. Plugins specific to IMAP,
16186 LDA, etc.@: are added to this list in their own .conf files.
16187 Defaults to @samp{()}.
16190 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
16191 The minimum number of mails in a mailbox before updates are done to
16192 cache file. This allows optimizing Dovecot's behavior to do less disk
16193 writes at the cost of more disk reads.
16194 Defaults to @samp{0}.
16197 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
16198 When IDLE command is running, mailbox is checked once in a while to
16199 see if there are any new mails or other changes. This setting defines
16200 the minimum time to wait between those checks. Dovecot can also use
16201 dnotify, inotify and kqueue to find out immediately when changes
16203 Defaults to @samp{"30 secs"}.
16206 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
16207 Save mails with CR+LF instead of plain LF. This makes sending those
16208 mails take less CPU, especially with sendfile() syscall with Linux and
16209 FreeBSD. But it also creates a bit more disk I/O which may just make it
16210 slower. Also note that if other software reads the mboxes/maildirs,
16211 they may handle the extra CRs wrong and cause problems.
16212 Defaults to @samp{#f}.
16215 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
16216 By default LIST command returns all entries in maildir beginning
16217 with a dot. Enabling this option makes Dovecot return only entries
16218 which are directories. This is done by stat()ing each entry, so it
16219 causes more disk I/O.
16220 (For systems setting struct @samp{dirent->d_type} this check is free
16221 and it's done always regardless of this setting).
16222 Defaults to @samp{#f}.
16225 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
16226 When copying a message, do it with hard links whenever possible.
16227 This makes the performance much better, and it's unlikely to have any
16229 Defaults to @samp{#t}.
16232 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
16233 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
16234 directory only when its mtime changes unexpectedly or when we can't find
16235 the mail otherwise.
16236 Defaults to @samp{#f}.
16239 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
16240 Which locking methods to use for locking mbox. There are four
16245 Create <mailbox>.lock file. This is the oldest and most NFS-safe
16246 solution. If you want to use /var/mail/ like directory, the users will
16247 need write access to that directory.
16249 Same as dotlock, but if it fails because of permissions or because there
16250 isn't enough disk space, just skip it.
16252 Use this if possible. Works with NFS too if lockd is used.
16254 May not exist in all systems. Doesn't work with NFS.
16256 May not exist in all systems. Doesn't work with NFS.
16259 You can use multiple locking methods; if you do the order they're declared
16260 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
16261 locking methods as well. Some operating systems don't allow using some of
16262 them simultaneously.
16265 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
16269 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
16270 Maximum time to wait for lock (all of them) before aborting.
16271 Defaults to @samp{"5 mins"}.
16274 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
16275 If dotlock exists but the mailbox isn't modified in any way,
16276 override the lock file after this much time.
16277 Defaults to @samp{"2 mins"}.
16280 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
16281 When mbox changes unexpectedly we have to fully read it to find out
16282 what changed. If the mbox is large this can take a long time. Since
16283 the change is usually just a newly appended mail, it'd be faster to
16284 simply read the new mails. If this setting is enabled, Dovecot does
16285 this but still safely fallbacks to re-reading the whole mbox file
16286 whenever something in mbox isn't how it's expected to be. The only real
16287 downside to this setting is that if some other MUA changes message
16288 flags, Dovecot doesn't notice it immediately. Note that a full sync is
16289 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
16290 Defaults to @samp{#t}.
16293 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
16294 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
16295 EXAMINE, EXPUNGE or CHECK commands. If this is set,
16296 @samp{mbox-dirty-syncs} is ignored.
16297 Defaults to @samp{#f}.
16300 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
16301 Delay writing mbox headers until doing a full write sync (EXPUNGE
16302 and CHECK commands and when closing the mailbox). This is especially
16303 useful for POP3 where clients often delete all mails. The downside is
16304 that our changes aren't immediately visible to other MUAs.
16305 Defaults to @samp{#t}.
16308 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
16309 If mbox size is smaller than this (e.g.@: 100k), don't write index
16310 files. If an index file already exists it's still read, just not
16312 Defaults to @samp{0}.
16315 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
16316 Maximum dbox file size until it's rotated.
16317 Defaults to @samp{10000000}.
16320 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
16321 Maximum dbox file age until it's rotated. Typically in days. Day
16322 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
16324 Defaults to @samp{"1d"}.
16327 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
16328 When creating new mdbox files, immediately preallocate their size to
16329 @samp{mdbox-rotate-size}. This setting currently works only in Linux
16330 with some file systems (ext4, xfs).
16331 Defaults to @samp{#f}.
16334 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
16335 sdbox and mdbox support saving mail attachments to external files,
16336 which also allows single instance storage for them. Other backends
16337 don't support this for now.
16339 WARNING: This feature hasn't been tested much yet. Use at your own risk.
16341 Directory root where to store mail attachments. Disabled, if empty.
16342 Defaults to @samp{""}.
16345 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
16346 Attachments smaller than this aren't saved externally. It's also
16347 possible to write a plugin to disable saving specific attachments
16349 Defaults to @samp{128000}.
16352 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
16353 File system backend to use for saving attachments:
16356 No SiS done by Dovecot (but this might help FS's own deduplication)
16358 SiS with immediate byte-by-byte comparison during saving
16359 @item sis-queue posix
16360 SiS with delayed comparison and deduplication.
16362 Defaults to @samp{"sis posix"}.
16365 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
16366 Hash format to use in attachment filenames. You can add any text and
16367 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
16368 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
16369 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
16370 Defaults to @samp{"%@{sha1@}"}.
16373 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
16375 Defaults to @samp{100}.
16378 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
16380 Defaults to @samp{1000}.
16383 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
16384 Default VSZ (virtual memory size) limit for service processes.
16385 This is mainly intended to catch and kill processes that leak memory
16386 before they eat up everything.
16387 Defaults to @samp{256000000}.
16390 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
16391 Login user is internally used by login processes. This is the most
16392 untrusted user in Dovecot system. It shouldn't have access to anything
16394 Defaults to @samp{"dovenull"}.
16397 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
16398 Internal user is used by unprivileged processes. It should be
16399 separate from login user, so that login processes can't disturb other
16401 Defaults to @samp{"dovecot"}.
16404 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
16405 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
16406 Defaults to @samp{"required"}.
16409 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
16410 PEM encoded X.509 SSL/TLS certificate (public key).
16411 Defaults to @samp{"</etc/dovecot/default.pem"}.
16414 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
16415 PEM encoded SSL/TLS private key. The key is opened before
16416 dropping root privileges, so keep the key file unreadable by anyone but
16418 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
16421 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
16422 If key file is password protected, give the password here.
16423 Alternatively give it when starting dovecot with -p parameter. Since
16424 this file is often world-readable, you may want to place this setting
16425 instead to a different.
16426 Defaults to @samp{""}.
16429 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
16430 PEM encoded trusted certificate authority. Set this only if you
16431 intend to use @samp{ssl-verify-client-cert? #t}. The file should
16432 contain the CA certificate(s) followed by the matching
16433 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
16434 Defaults to @samp{""}.
16437 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
16438 Require that CRL check succeeds for client certificates.
16439 Defaults to @samp{#t}.
16442 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
16443 Request client to send a certificate. If you also want to require
16444 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
16445 Defaults to @samp{#f}.
16448 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
16449 Which field from certificate to use for username. commonName and
16450 x500UniqueIdentifier are the usual choices. You'll also need to set
16451 @samp{auth-ssl-username-from-cert? #t}.
16452 Defaults to @samp{"commonName"}.
16455 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
16456 Minimum SSL protocol version to accept.
16457 Defaults to @samp{"TLSv1"}.
16460 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
16461 SSL ciphers to use.
16462 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
16465 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
16466 SSL crypto device to use, for valid values run "openssl engine".
16467 Defaults to @samp{""}.
16470 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
16471 Address to use when sending rejection mails.
16472 %d expands to recipient domain.
16473 Defaults to @samp{"postmaster@@%d"}.
16476 @deftypevr {@code{dovecot-configuration} parameter} string hostname
16477 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
16478 and in LMTP replies. Default is the system's real hostname@@domain.
16479 Defaults to @samp{""}.
16482 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
16483 If user is over quota, return with temporary failure instead of
16485 Defaults to @samp{#f}.
16488 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
16489 Binary to use for sending mails.
16490 Defaults to @samp{"/usr/sbin/sendmail"}.
16493 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
16494 If non-empty, send mails via this SMTP host[:port] instead of
16496 Defaults to @samp{""}.
16499 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
16500 Subject: header to use for rejection mails. You can use the same
16501 variables as for @samp{rejection-reason} below.
16502 Defaults to @samp{"Rejected: %s"}.
16505 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
16506 Human readable error message for rejection mails. You can use
16519 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
16522 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
16523 Delimiter character between local-part and detail in email
16525 Defaults to @samp{"+"}.
16528 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
16529 Header where the original recipient address (SMTP's RCPT TO:
16530 address) is taken from if not available elsewhere. With dovecot-lda -a
16531 parameter overrides this. A commonly used header for this is
16533 Defaults to @samp{""}.
16536 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
16537 Should saving a mail to a nonexistent mailbox automatically create
16539 Defaults to @samp{#f}.
16542 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
16543 Should automatically created mailboxes be also automatically
16545 Defaults to @samp{#f}.
16548 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
16549 Maximum IMAP command line length. Some clients generate very long
16550 command lines with huge mailboxes, so you may need to raise this if you
16551 get "Too long argument" or "IMAP command line too large" errors
16553 Defaults to @samp{64000}.
16556 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
16557 IMAP logout format string:
16560 total number of bytes read from client
16562 total number of bytes sent to client.
16564 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
16565 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@}"}.
16568 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
16569 Override the IMAP CAPABILITY response. If the value begins with '+',
16570 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
16571 Defaults to @samp{""}.
16574 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
16575 How long to wait between "OK Still here" notifications when client
16577 Defaults to @samp{"2 mins"}.
16580 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
16581 ID field names and values to send to clients. Using * as the value
16582 makes Dovecot use the default value. The following fields have default
16583 values currently: name, version, os, os-version, support-url,
16585 Defaults to @samp{""}.
16588 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
16589 ID fields sent by client to log. * means everything.
16590 Defaults to @samp{""}.
16593 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
16594 Workarounds for various client bugs:
16597 @item delay-newmail
16598 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
16599 CHECK commands. Some clients ignore them otherwise, for example OSX
16600 Mail (<v2.1). Outlook Express breaks more badly though, without this it
16601 may show user "Message no longer in server" errors. Note that OE6
16602 still breaks even with this workaround if synchronization is set to
16605 @item tb-extra-mailbox-sep
16606 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
16607 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
16608 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
16610 @item tb-lsub-flags
16611 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
16612 This makes Thunderbird realize they aren't selectable and show them
16613 greyed out, instead of only later giving "not selectable" popup error.
16615 Defaults to @samp{()}.
16618 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
16619 Host allowed in URLAUTH URLs sent by client. "*" allows all.
16620 Defaults to @samp{""}.
16624 Whew! Lots of configuration options. The nice thing about it though is
16625 that Guix has a complete interface to Dovecot's configuration
16626 language. This allows not only a nice way to declare configurations,
16627 but also offers reflective capabilities as well: users can write code to
16628 inspect and transform configurations from within Scheme.
16630 However, it could be that you just want to get a @code{dovecot.conf} up
16631 and running. In that case, you can pass an
16632 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
16633 @code{dovecot-service}. As its name indicates, an opaque configuration
16634 does not have easy reflective capabilities.
16636 Available @code{opaque-dovecot-configuration} fields are:
16638 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
16639 The dovecot package.
16642 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
16643 The contents of the @code{dovecot.conf}, as a string.
16646 For example, if your @code{dovecot.conf} is just the empty string, you
16647 could instantiate a dovecot service like this:
16650 (dovecot-service #:config
16651 (opaque-dovecot-configuration
16655 @subsubheading OpenSMTPD Service
16657 @deffn {Scheme Variable} opensmtpd-service-type
16658 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
16659 service, whose value should be an @code{opensmtpd-configuration} object
16660 as in this example:
16663 (service opensmtpd-service-type
16664 (opensmtpd-configuration
16665 (config-file (local-file "./my-smtpd.conf"))))
16669 @deftp {Data Type} opensmtpd-configuration
16670 Data type representing the configuration of opensmtpd.
16673 @item @code{package} (default: @var{opensmtpd})
16674 Package object of the OpenSMTPD SMTP server.
16676 @item @code{config-file} (default: @var{%default-opensmtpd-file})
16677 File-like object of the OpenSMTPD configuration file to use. By default
16678 it listens on the loopback network interface, and allows for mail from
16679 users and daemons on the local machine, as well as permitting email to
16680 remote servers. Run @command{man smtpd.conf} for more information.
16685 @subsubheading Exim Service
16687 @cindex mail transfer agent (MTA)
16688 @cindex MTA (mail transfer agent)
16691 @deffn {Scheme Variable} exim-service-type
16692 This is the type of the @uref{https://exim.org, Exim} mail transfer
16693 agent (MTA), whose value should be an @code{exim-configuration} object
16694 as in this example:
16697 (service exim-service-type
16698 (exim-configuration
16699 (config-file (local-file "./my-exim.conf"))))
16703 In order to use an @code{exim-service-type} service you must also have a
16704 @code{mail-aliases-service-type} service present in your
16705 @code{operating-system} (even if it has no aliases).
16707 @deftp {Data Type} exim-configuration
16708 Data type representing the configuration of exim.
16711 @item @code{package} (default: @var{exim})
16712 Package object of the Exim server.
16714 @item @code{config-file} (default: @code{#f})
16715 File-like object of the Exim configuration file to use. If its value is
16716 @code{#f} then use the default configuration file from the package
16717 provided in @code{package}. The resulting configuration file is loaded
16718 after setting the @code{exim_user} and @code{exim_group} configuration
16724 @subsubheading Getmail service
16729 @deffn {Scheme Variable} getmail-service-type
16730 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
16731 mail retriever, whose value should be an @code{getmail-configuration}.
16734 Available @code{getmail-configuration} fields are:
16736 @deftypevr {@code{getmail-configuration} parameter} symbol name
16737 A symbol to identify the getmail service.
16739 Defaults to @samp{"unset"}.
16743 @deftypevr {@code{getmail-configuration} parameter} package package
16744 The getmail package to use.
16748 @deftypevr {@code{getmail-configuration} parameter} string user
16749 The user to run getmail as.
16751 Defaults to @samp{"getmail"}.
16755 @deftypevr {@code{getmail-configuration} parameter} string group
16756 The group to run getmail as.
16758 Defaults to @samp{"getmail"}.
16762 @deftypevr {@code{getmail-configuration} parameter} string directory
16763 The getmail directory to use.
16765 Defaults to @samp{"/var/lib/getmail/default"}.
16769 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
16770 The getmail configuration file to use.
16772 Available @code{getmail-configuration-file} fields are:
16774 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
16775 What mail account to retrieve mail from, and how to access that account.
16777 Available @code{getmail-retriever-configuration} fields are:
16779 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
16780 The type of mail retriever to use. Valid values include @samp{passwd}
16783 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
16787 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
16788 Space separated list of arguments to the userdb driver.
16790 Defaults to @samp{unset}.
16794 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
16795 Space separated list of arguments to the userdb driver.
16797 Defaults to @samp{unset}.
16801 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
16802 Space separated list of arguments to the userdb driver.
16804 Defaults to @samp{#f}.
16808 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
16809 Override fields from passwd.
16811 Defaults to @samp{""}.
16815 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
16816 Override fields from passwd.
16818 Defaults to @samp{()}.
16822 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
16823 PEM-formatted key file to use for the TLS negotiation
16825 Defaults to @samp{""}.
16829 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
16830 PEM-formatted certificate file to use for the TLS negotiation
16832 Defaults to @samp{""}.
16836 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
16837 CA certificates to use
16839 Defaults to @samp{""}.
16843 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
16844 Extra retriever parameters
16846 Defaults to @samp{()}.
16852 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
16853 What to do with retrieved messages.
16855 Available @code{getmail-destination-configuration} fields are:
16857 @deftypevr {@code{getmail-destination-configuration} parameter} string type
16858 The type of mail destination. Valid values include @samp{Maildir},
16859 @samp{Mboxrd} and @samp{MDA_external}.
16861 Defaults to @samp{unset}.
16865 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
16866 The path option for the mail destination. The behaviour depends on the
16869 Defaults to @samp{""}.
16873 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
16874 Extra destination parameters
16876 Defaults to @samp{()}.
16882 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
16885 Available @code{getmail-options-configuration} fields are:
16887 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
16888 If set to @samp{0}, getmail will only print warnings and errors. A
16889 value of @samp{1} means that messages will be printed about retrieving
16890 and deleting messages. If set to @samp{2}, getmail will print messages
16891 about each of it's actions.
16893 Defaults to @samp{1}.
16897 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
16898 If true, getmail will retrieve all available messages. Otherwise it
16899 will only retrieve messages it hasn't seen previously.
16901 Defaults to @samp{#t}.
16905 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
16906 If set to true, messages will be deleted from the server after
16907 retrieving and successfully delivering them. Otherwise, messages will
16908 be left on the server.
16910 Defaults to @samp{#f}.
16914 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
16915 Getmail will delete messages this number of days after seeing them, if
16916 they have not been delivered. This means messages will be left on the
16917 server this number of days after delivering them. A value of @samp{0}
16918 disabled this feature.
16920 Defaults to @samp{0}.
16924 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
16925 Delete messages larger than this of bytes after retrieving them, even if
16926 the delete and delete-after options are disabled. A value of @samp{0}
16927 disables this feature.
16929 Defaults to @samp{0}.
16933 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
16934 Retrieve messages totalling up to this number of bytes before closing
16935 the session with the server. A value of @samp{0} disables this feature.
16937 Defaults to @samp{0}.
16941 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
16942 Don't retrieve messages larger than this number of bytes. A value of
16943 @samp{0} disables this feature.
16945 Defaults to @samp{0}.
16949 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
16950 If true, getmail will add a Delivered-To header to messages.
16952 Defaults to @samp{#t}.
16956 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
16957 If set, getmail adds a Received header to the messages.
16959 Defaults to @samp{#t}.
16963 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
16964 Getmail will record a log of its actions to the named file. A value of
16965 @samp{""} disables this feature.
16967 Defaults to @samp{""}.
16971 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
16972 If true, getmail will record a log of its actions using the system
16975 Defaults to @samp{#t}.
16979 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
16980 If true, getmail will log information about messages not retrieved and
16981 the reason for not retrieving them, as well as starting and ending
16984 Defaults to @samp{#t}.
16988 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
16989 Extra options to include.
16991 Defaults to @samp{()}.
16999 @deftypevr {@code{getmail-configuration} parameter} list idle
17000 A list of mailboxes that getmail should wait on the server for new mail
17001 notifications. This depends on the server supporting the IDLE
17004 Defaults to @samp{()}.
17008 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
17009 Environment variables to set for getmail.
17011 Defaults to @samp{()}.
17015 @subsubheading Mail Aliases Service
17017 @cindex email aliases
17018 @cindex aliases, for email addresses
17020 @deffn {Scheme Variable} mail-aliases-service-type
17021 This is the type of the service which provides @code{/etc/aliases},
17022 specifying how to deliver mail to users on this system.
17025 (service mail-aliases-service-type
17026 '(("postmaster" "bob")
17027 ("bob" "bob@@example.com" "bob@@example2.com")))
17031 The configuration for a @code{mail-aliases-service-type} service is an
17032 association list denoting how to deliver mail that comes to this
17033 system. Each entry is of the form @code{(alias addresses ...)}, with
17034 @code{alias} specifying the local alias and @code{addresses} specifying
17035 where to deliver this user's mail.
17037 The aliases aren't required to exist as users on the local system. In
17038 the above example, there doesn't need to be a @code{postmaster} entry in
17039 the @code{operating-system}'s @code{user-accounts} in order to deliver
17040 the @code{postmaster} mail to @code{bob} (which subsequently would
17041 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
17043 @subsubheading GNU Mailutils IMAP4 Daemon
17044 @cindex GNU Mailutils IMAP4 Daemon
17046 @deffn {Scheme Variable} imap4d-service-type
17047 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
17048 mailutils, GNU Mailutils Manual}), whose value should be an
17049 @code{imap4d-configuration} object as in this example:
17052 (service imap4d-service-type
17053 (imap4d-configuration
17054 (config-file (local-file "imap4d.conf"))))
17058 @deftp {Data Type} imap4d-configuration
17059 Data type representing the configuration of @command{imap4d}.
17062 @item @code{package} (default: @code{mailutils})
17063 The package that provides @command{imap4d}.
17065 @item @code{config-file} (default: @code{%default-imap4d-config-file})
17066 File-like object of the configuration file to use, by default it will listen
17067 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
17068 Mailutils Manual}, for details.
17073 @node Messaging Services
17074 @subsection Messaging Services
17079 The @code{(gnu services messaging)} module provides Guix service
17080 definitions for messaging services: currently only Prosody is supported.
17082 @subsubheading Prosody Service
17084 @deffn {Scheme Variable} prosody-service-type
17085 This is the type for the @uref{https://prosody.im, Prosody XMPP
17086 communication server}. Its value must be a @code{prosody-configuration}
17087 record as in this example:
17090 (service prosody-service-type
17091 (prosody-configuration
17092 (modules-enabled (cons "groups" "mam" %default-modules-enabled))
17095 (int-component-configuration
17096 (hostname "conference.example.net")
17098 (mod-muc (mod-muc-configuration)))))
17101 (virtualhost-configuration
17102 (domain "example.net"))))))
17105 See below for details about @code{prosody-configuration}.
17109 By default, Prosody does not need much configuration. Only one
17110 @code{virtualhosts} field is needed: it specifies the domain you wish
17113 You can perform various sanity checks on the generated configuration
17114 with the @code{prosodyctl check} command.
17116 Prosodyctl will also help you to import certificates from the
17117 @code{letsencrypt} directory so that the @code{prosody} user can access
17118 them. See @url{https://prosody.im/doc/letsencrypt}.
17121 prosodyctl --root cert import /etc/letsencrypt/live
17124 The available configuration parameters follow. Each parameter
17125 definition is preceded by its type; for example, @samp{string-list foo}
17126 indicates that the @code{foo} parameter should be specified as a list of
17127 strings. Types starting with @code{maybe-} denote parameters that won't
17128 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
17130 There is also a way to specify the configuration as a string, if you
17131 have an old @code{prosody.cfg.lua} file that you want to port over from
17132 some other system; see the end for more details.
17134 The @code{file-object} type designates either a file-like object
17135 (@pxref{G-Expressions, file-like objects}) or a file name.
17137 @c The following documentation was initially generated by
17138 @c (generate-documentation) in (gnu services messaging). Manually maintained
17139 @c documentation is better, so we shouldn't hesitate to edit below as
17140 @c needed. However if the change you want to make to this documentation
17141 @c can be done in an automated way, it's probably easier to change
17142 @c (generate-documentation) than to make it below and have to deal with
17143 @c the churn as Prosody updates.
17145 Available @code{prosody-configuration} fields are:
17147 @deftypevr {@code{prosody-configuration} parameter} package prosody
17148 The Prosody package.
17151 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
17152 Location of the Prosody data storage directory. See
17153 @url{https://prosody.im/doc/configure}.
17154 Defaults to @samp{"/var/lib/prosody"}.
17157 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
17158 Additional plugin directories. They are searched in all the specified
17159 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
17160 Defaults to @samp{()}.
17163 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
17164 Every virtual host and component needs a certificate so that clients and
17165 servers can securely verify its identity. Prosody will automatically load
17166 certificates/keys from the directory specified here.
17167 Defaults to @samp{"/etc/prosody/certs"}.
17170 @deftypevr {@code{prosody-configuration} parameter} string-list admins
17171 This is a list of accounts that are admins for the server. Note that you
17172 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
17173 @url{https://prosody.im/doc/creating_accounts}.
17174 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
17175 Defaults to @samp{()}.
17178 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
17179 Enable use of libevent for better performance under high load. See
17180 @url{https://prosody.im/doc/libevent}.
17181 Defaults to @samp{#f}.
17184 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
17185 This is the list of modules Prosody will load on startup. It looks for
17186 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
17187 Documentation on modules can be found at:
17188 @url{https://prosody.im/doc/modules}.
17189 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
17192 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
17193 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
17194 should you want to disable them then add them to this list.
17195 Defaults to @samp{()}.
17198 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
17199 Path to a text file where the shared groups are defined. If this path is
17200 empty then @samp{mod_groups} does nothing. See
17201 @url{https://prosody.im/doc/modules/mod_groups}.
17202 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
17205 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
17206 Disable account creation by default, for security. See
17207 @url{https://prosody.im/doc/creating_accounts}.
17208 Defaults to @samp{#f}.
17211 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
17212 These are the SSL/TLS-related settings. Most of them are disabled so to
17213 use Prosody's defaults. If you do not completely understand these options, do
17214 not add them to your config, it is easy to lower the security of your server
17215 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
17217 Available @code{ssl-configuration} fields are:
17219 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
17220 This determines what handshake to use.
17223 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
17224 Path to your private key file.
17227 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
17228 Path to your certificate file.
17231 @deftypevr {@code{ssl-configuration} parameter} file-object capath
17232 Path to directory containing root certificates that you wish Prosody to
17233 trust when verifying the certificates of remote servers.
17234 Defaults to @samp{"/etc/ssl/certs"}.
17237 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
17238 Path to a file containing root certificates that you wish Prosody to trust.
17239 Similar to @code{capath} but with all certificates concatenated together.
17242 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
17243 A list of verification options (these mostly map to OpenSSL's
17244 @code{set_verify()} flags).
17247 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
17248 A list of general options relating to SSL/TLS. These map to OpenSSL's
17249 @code{set_options()}. For a full list of options available in LuaSec, see the
17253 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
17254 How long a chain of certificate authorities to check when looking for a
17255 trusted root certificate.
17258 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
17259 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
17260 clients, and in what order.
17263 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
17264 A path to a file containing parameters for Diffie-Hellman key exchange. You
17265 can create such a file with:
17266 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
17269 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
17270 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
17271 @samp{"secp384r1"}.
17274 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
17275 A list of "extra" verification options.
17278 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
17279 Password for encrypted private keys.
17284 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
17285 Whether to force all client-to-server connections to be encrypted or not.
17286 See @url{https://prosody.im/doc/modules/mod_tls}.
17287 Defaults to @samp{#f}.
17290 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
17291 Set of mechanisms that will never be offered. See
17292 @url{https://prosody.im/doc/modules/mod_saslauth}.
17293 Defaults to @samp{("DIGEST-MD5")}.
17296 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
17297 Whether to force all server-to-server connections to be encrypted or not.
17298 See @url{https://prosody.im/doc/modules/mod_tls}.
17299 Defaults to @samp{#f}.
17302 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
17303 Whether to require encryption and certificate authentication. This
17304 provides ideal security, but requires servers you communicate with to support
17305 encryption AND present valid, trusted certificates. See
17306 @url{https://prosody.im/doc/s2s#security}.
17307 Defaults to @samp{#f}.
17310 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
17311 Many servers don't support encryption or have invalid or self-signed
17312 certificates. You can list domains here that will not be required to
17313 authenticate using certificates. They will be authenticated using DNS. See
17314 @url{https://prosody.im/doc/s2s#security}.
17315 Defaults to @samp{()}.
17318 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
17319 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
17320 valid certificates for some domains by specifying a list here. See
17321 @url{https://prosody.im/doc/s2s#security}.
17322 Defaults to @samp{()}.
17325 @deftypevr {@code{prosody-configuration} parameter} string authentication
17326 Select the authentication backend to use. The default provider stores
17327 passwords in plaintext and uses Prosody's configured data storage to store the
17328 authentication data. If you do not trust your server please see
17329 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
17330 about using the hashed backend. See also
17331 @url{https://prosody.im/doc/authentication}
17332 Defaults to @samp{"internal_plain"}.
17335 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
17336 Set logging options. Advanced logging configuration is not yet supported
17337 by the Prosody service. See @url{https://prosody.im/doc/logging}.
17338 Defaults to @samp{"*syslog"}.
17341 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
17342 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
17343 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
17346 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
17347 Maximum allowed size of the HTTP body (in bytes).
17350 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
17351 Some modules expose their own URL in various ways. This URL is built
17352 from the protocol, host and port used. If Prosody sits behind a proxy, the
17353 public URL will be @code{http-external-url} instead. See
17354 @url{https://prosody.im/doc/http#external_url}.
17357 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
17358 A host in Prosody is a domain on which user accounts can be created. For
17359 example if you want your users to have addresses like
17360 @samp{"john.smith@@example.com"} then you need to add a host
17361 @samp{"example.com"}. All options in this list will apply only to this host.
17363 Note: the name "virtual" host is used in configuration to avoid confusion with
17364 the actual physical host that Prosody is installed on. A single Prosody
17365 instance can serve many domains, each one defined as a VirtualHost entry in
17366 Prosody's configuration. Conversely a server that hosts a single domain would
17367 have just one VirtualHost entry.
17369 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
17371 Available @code{virtualhost-configuration} fields are:
17373 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:
17374 @deftypevr {@code{virtualhost-configuration} parameter} string domain
17375 Domain you wish Prosody to serve.
17380 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
17381 Components are extra services on a server which are available to clients,
17382 usually on a subdomain of the main server (such as
17383 @samp{"mycomponent.example.com"}). Example components might be chatroom
17384 servers, user directories, or gateways to other protocols.
17386 Internal components are implemented with Prosody-specific plugins. To add an
17387 internal component, you simply fill the hostname field, and the plugin you wish
17388 to use for the component.
17390 See @url{https://prosody.im/doc/components}.
17391 Defaults to @samp{()}.
17393 Available @code{int-component-configuration} fields are:
17395 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:
17396 @deftypevr {@code{int-component-configuration} parameter} string hostname
17397 Hostname of the component.
17400 @deftypevr {@code{int-component-configuration} parameter} string plugin
17401 Plugin you wish to use for the component.
17404 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
17405 Multi-user chat (MUC) is Prosody's module for allowing you to create
17406 hosted chatrooms/conferences for XMPP users.
17408 General information on setting up and using multi-user chatrooms can be found
17409 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
17410 which you should read if you are new to XMPP chatrooms.
17412 See also @url{https://prosody.im/doc/modules/mod_muc}.
17414 Available @code{mod-muc-configuration} fields are:
17416 @deftypevr {@code{mod-muc-configuration} parameter} string name
17417 The name to return in service discovery responses.
17418 Defaults to @samp{"Prosody Chatrooms"}.
17421 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
17422 If @samp{#t}, this will only allow admins to create new chatrooms.
17423 Otherwise anyone can create a room. The value @samp{"local"} restricts room
17424 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
17425 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
17426 restricts to service administrators only.
17427 Defaults to @samp{#f}.
17430 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
17431 Maximum number of history messages that will be sent to the member that has
17432 just joined the room.
17433 Defaults to @samp{20}.
17440 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
17441 External components use XEP-0114, which most standalone components
17442 support. To add an external component, you simply fill the hostname field. See
17443 @url{https://prosody.im/doc/components}.
17444 Defaults to @samp{()}.
17446 Available @code{ext-component-configuration} fields are:
17448 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:
17449 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
17450 Password which the component will use to log in.
17453 @deftypevr {@code{ext-component-configuration} parameter} string hostname
17454 Hostname of the component.
17459 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
17460 Port(s) Prosody listens on for component connections.
17461 Defaults to @samp{(5347)}.
17464 @deftypevr {@code{prosody-configuration} parameter} string component-interface
17465 Interface Prosody listens on for component connections.
17466 Defaults to @samp{"127.0.0.1"}.
17469 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
17470 Raw content that will be added to the configuration file.
17473 It could be that you just want to get a @code{prosody.cfg.lua}
17474 up and running. In that case, you can pass an
17475 @code{opaque-prosody-configuration} record as the value of
17476 @code{prosody-service-type}. As its name indicates, an opaque configuration
17477 does not have easy reflective capabilities.
17478 Available @code{opaque-prosody-configuration} fields are:
17480 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
17481 The prosody package.
17484 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
17485 The contents of the @code{prosody.cfg.lua} to use.
17488 For example, if your @code{prosody.cfg.lua} is just the empty
17489 string, you could instantiate a prosody service like this:
17492 (service prosody-service-type
17493 (opaque-prosody-configuration
17494 (prosody.cfg.lua "")))
17497 @c end of Prosody auto-generated documentation
17499 @subsubheading BitlBee Service
17501 @cindex IRC (Internet Relay Chat)
17502 @cindex IRC gateway
17503 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
17504 interface to a variety of messaging protocols such as XMPP.
17506 @defvr {Scheme Variable} bitlbee-service-type
17507 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
17508 gateway daemon. Its value is a @code{bitlbee-configuration} (see
17511 To have BitlBee listen on port 6667 on localhost, add this line to your
17515 (service bitlbee-service-type)
17519 @deftp {Data Type} bitlbee-configuration
17520 This is the configuration for BitlBee, with the following fields:
17523 @item @code{interface} (default: @code{"127.0.0.1"})
17524 @itemx @code{port} (default: @code{6667})
17525 Listen on the network interface corresponding to the IP address
17526 specified in @var{interface}, on @var{port}.
17528 When @var{interface} is @code{127.0.0.1}, only local clients can
17529 connect; when it is @code{0.0.0.0}, connections can come from any
17530 networking interface.
17532 @item @code{package} (default: @code{bitlbee})
17533 The BitlBee package to use.
17535 @item @code{plugins} (default: @code{'()})
17536 List of plugin packages to use---e.g., @code{bitlbee-discord}.
17538 @item @code{extra-settings} (default: @code{""})
17539 Configuration snippet added as-is to the BitlBee configuration file.
17543 @subsubheading Quassel Service
17545 @cindex IRC (Internet Relay Chat)
17546 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
17547 meaning that one or more clients can attach to and detach from the
17550 @defvr {Scheme Variable} quassel-service-type
17551 This is the service type for the @url{https://quassel-irc.org/,Quassel}
17552 IRC backend daemon. Its value is a @code{quassel-configuration}
17556 @deftp {Data Type} quassel-configuration
17557 This is the configuration for Quassel, with the following fields:
17560 @item @code{quassel} (default: @code{quassel})
17561 The Quassel package to use.
17563 @item @code{interface} (default: @code{"::,0.0.0.0"})
17564 @item @code{port} (default: @code{4242})
17565 Listen on the network interface(s) corresponding to the IPv4 or IPv6
17566 interfaces specified in the comma delimited @var{interface}, on
17569 @item @code{loglevel} (default: @code{"Info"})
17570 The level of logging desired. Accepted values are Debug, Info, Warning
17575 @node Telephony Services
17576 @subsection Telephony Services
17578 @cindex Murmur (VoIP server)
17579 @cindex VoIP server
17580 This section describes how to set up and run a Murmur server. Murmur is
17581 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
17584 @deftp {Data Type} murmur-configuration
17585 The service type for the Murmur server. An example configuration can
17589 (service murmur-service-type
17590 (murmur-configuration
17592 "Welcome to this Mumble server running on Guix!")
17593 (cert-required? #t) ;disallow text password logins
17594 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
17595 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
17598 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
17599 password with the command that is printed during the activation phase.
17601 It is recommended to register a normal Mumble user account
17602 and grant it admin or moderator rights.
17603 You can use the @code{mumble} client to
17604 login as new normal user, register yourself, and log out.
17605 For the next step login with the name @code{SuperUser} use
17606 the @code{SuperUser} password that you set previously,
17607 and grant your newly registered mumble user administrator or moderator
17608 rights and create some channels.
17610 Available @code{murmur-configuration} fields are:
17613 @item @code{package} (default: @code{mumble})
17614 Package that contains @code{bin/murmurd}.
17616 @item @code{user} (default: @code{"murmur"})
17617 User who will run the Murmur server.
17619 @item @code{group} (default: @code{"murmur"})
17620 Group of the user who will run the murmur server.
17622 @item @code{port} (default: @code{64738})
17623 Port on which the server will listen.
17625 @item @code{welcome-text} (default: @code{""})
17626 Welcome text sent to clients when they connect.
17628 @item @code{server-password} (default: @code{""})
17629 Password the clients have to enter in order to connect.
17631 @item @code{max-users} (default: @code{100})
17632 Maximum of users that can be connected to the server at once.
17634 @item @code{max-user-bandwidth} (default: @code{#f})
17635 Maximum voice traffic a user can send per second.
17637 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
17638 File name of the sqlite database.
17639 The service's user will become the owner of the directory.
17641 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
17642 File name of the log file.
17643 The service's user will become the owner of the directory.
17645 @item @code{autoban-attempts} (default: @code{10})
17646 Maximum number of logins a user can make in @code{autoban-timeframe}
17647 without getting auto banned for @code{autoban-time}.
17649 @item @code{autoban-timeframe} (default: @code{120})
17650 Timeframe for autoban in seconds.
17652 @item @code{autoban-time} (default: @code{300})
17653 Amount of time in seconds for which a client gets banned
17654 when violating the autoban limits.
17656 @item @code{opus-threshold} (default: @code{100})
17657 Percentage of clients that need to support opus
17658 before switching over to opus audio codec.
17660 @item @code{channel-nesting-limit} (default: @code{10})
17661 How deep channels can be nested at maximum.
17663 @item @code{channelname-regex} (default: @code{#f})
17664 A string in form of a Qt regular expression that channel names must conform to.
17666 @item @code{username-regex} (default: @code{#f})
17667 A string in form of a Qt regular expression that user names must conform to.
17669 @item @code{text-message-length} (default: @code{5000})
17670 Maximum size in bytes that a user can send in one text chat message.
17672 @item @code{image-message-length} (default: @code{(* 128 1024)})
17673 Maximum size in bytes that a user can send in one image message.
17675 @item @code{cert-required?} (default: @code{#f})
17676 If it is set to @code{#t} clients that use weak password authentication
17677 will not be accepted. Users must have completed the certificate wizard to join.
17679 @item @code{remember-channel?} (default: @code{#f})
17680 Should murmur remember the last channel each user was in when they disconnected
17681 and put them into the remembered channel when they rejoin.
17683 @item @code{allow-html?} (default: @code{#f})
17684 Should html be allowed in text messages, user comments, and channel descriptions.
17686 @item @code{allow-ping?} (default: @code{#f})
17687 Setting to true exposes the current user count, the maximum user count, and
17688 the server's maximum bandwidth per client to unauthenticated users. In the
17689 Mumble client, this information is shown in the Connect dialog.
17691 Disabling this setting will prevent public listing of the server.
17693 @item @code{bonjour?} (default: @code{#f})
17694 Should the server advertise itself in the local network through the bonjour protocol.
17696 @item @code{send-version?} (default: @code{#f})
17697 Should the murmur server version be exposed in ping requests.
17699 @item @code{log-days} (default: @code{31})
17700 Murmur also stores logs in the database, which are accessible via RPC.
17701 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
17702 or -1 to disable logging to the database.
17704 @item @code{obfuscate-ips?} (default: @code{#t})
17705 Should logged ips be obfuscated to protect the privacy of users.
17707 @item @code{ssl-cert} (default: @code{#f})
17708 File name of the SSL/TLS certificate used for encrypted connections.
17711 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
17713 @item @code{ssl-key} (default: @code{#f})
17714 Filepath to the ssl private key used for encrypted connections.
17716 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
17719 @item @code{ssl-dh-params} (default: @code{#f})
17720 File name of a PEM-encoded file with Diffie-Hellman parameters
17721 for the SSL/TLS encryption. Alternatively you set it to
17722 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
17723 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
17725 @item @code{ssl-ciphers} (default: @code{#f})
17726 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
17729 This option is specified using
17730 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
17731 OpenSSL cipher list notation}.
17733 It is recommended that you try your cipher string using 'openssl ciphers <string>'
17734 before setting it here, to get a feel for which cipher suites you will get.
17735 After setting this option, it is recommend that you inspect your Murmur log
17736 to ensure that Murmur is using the cipher suites that you expected it to.
17738 Note: Changing this option may impact the backwards compatibility of your
17739 Murmur server, and can remove the ability for older Mumble clients to be able
17742 @item @code{public-registration} (default: @code{#f})
17743 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
17745 You can optionally register your server in the public server list that the
17746 @code{mumble} client shows on startup.
17747 You cannot register your server if you have set a @code{server-password},
17748 or set @code{allow-ping} to @code{#f}.
17750 It might take a few hours until it shows up in the public list.
17752 @item @code{file} (default: @code{#f})
17753 Optional alternative override for this configuration.
17757 @deftp {Data Type} murmur-public-registration-configuration
17758 Configuration for public registration of a murmur service.
17762 This is a display name for your server. Not to be confused with the hostname.
17764 @item @code{password}
17765 A password to identify your registration.
17766 Subsequent updates will need the same password. Don't lose your password.
17769 This should be a @code{http://} or @code{https://} link to your web
17772 @item @code{hostname} (default: @code{#f})
17773 By default your server will be listed by its IP address.
17774 If it is set your server will be linked by this host name instead.
17780 @node Monitoring Services
17781 @subsection Monitoring Services
17783 @subsubheading Tailon Service
17785 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
17786 viewing and searching log files.
17788 The following example will configure the service with default values.
17789 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
17792 (service tailon-service-type)
17795 The following example customises more of the Tailon configuration,
17796 adding @command{sed} to the list of allowed commands.
17799 (service tailon-service-type
17800 (tailon-configuration
17802 (tailon-configuration-file
17803 (allowed-commands '("tail" "grep" "awk" "sed"))))))
17807 @deftp {Data Type} tailon-configuration
17808 Data type representing the configuration of Tailon.
17809 This type has the following parameters:
17812 @item @code{config-file} (default: @code{(tailon-configuration-file)})
17813 The configuration file to use for Tailon. This can be set to a
17814 @dfn{tailon-configuration-file} record value, or any gexp
17815 (@pxref{G-Expressions}).
17817 For example, to instead use a local file, the @code{local-file} function
17821 (service tailon-service-type
17822 (tailon-configuration
17823 (config-file (local-file "./my-tailon.conf"))))
17826 @item @code{package} (default: @code{tailon})
17827 The tailon package to use.
17832 @deftp {Data Type} tailon-configuration-file
17833 Data type representing the configuration options for Tailon.
17834 This type has the following parameters:
17837 @item @code{files} (default: @code{(list "/var/log")})
17838 List of files to display. The list can include strings for a single file
17839 or directory, or a list, where the first item is the name of a
17840 subsection, and the remaining items are the files or directories in that
17843 @item @code{bind} (default: @code{"localhost:8080"})
17844 Address and port to which Tailon should bind on.
17846 @item @code{relative-root} (default: @code{#f})
17847 URL path to use for Tailon, set to @code{#f} to not use a path.
17849 @item @code{allow-transfers?} (default: @code{#t})
17850 Allow downloading the log files in the web interface.
17852 @item @code{follow-names?} (default: @code{#t})
17853 Allow tailing of not-yet existent files.
17855 @item @code{tail-lines} (default: @code{200})
17856 Number of lines to read initially from each file.
17858 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
17859 Commands to allow running. By default, @code{sed} is disabled.
17861 @item @code{debug?} (default: @code{#f})
17862 Set @code{debug?} to @code{#t} to show debug messages.
17864 @item @code{wrap-lines} (default: @code{#t})
17865 Initial line wrapping state in the web interface. Set to @code{#t} to
17866 initially wrap lines (the default), or to @code{#f} to initially not
17869 @item @code{http-auth} (default: @code{#f})
17870 HTTP authentication type to use. Set to @code{#f} to disable
17871 authentication (the default). Supported values are @code{"digest"} or
17874 @item @code{users} (default: @code{#f})
17875 If HTTP authentication is enabled (see @code{http-auth}), access will be
17876 restricted to the credentials provided here. To configure users, use a
17877 list of pairs, where the first element of the pair is the username, and
17878 the 2nd element of the pair is the password.
17881 (tailon-configuration-file
17882 (http-auth "basic")
17883 (users '(("user1" . "password1")
17884 ("user2" . "password2"))))
17891 @subsubheading Darkstat Service
17893 Darkstat is a packet sniffer that captures network traffic, calculates
17894 statistics about usage, and serves reports over HTTP.
17896 @defvar {Scheme Variable} darkstat-service-type
17897 This is the service type for the
17898 @uref{https://unix4lyfe.org/darkstat/, darkstat}
17899 service, its value must be a @code{darkstat-configuration} record as in
17903 (service darkstat-service-type
17904 (darkstat-configuration
17905 (interface "eno1")))
17909 @deftp {Data Type} darkstat-configuration
17910 Data type representing the configuration of @command{darkstat}.
17913 @item @code{package} (default: @code{darkstat})
17914 The darkstat package to use.
17916 @item @code{interface}
17917 Capture traffic on the specified network interface.
17919 @item @code{port} (default: @code{"667"})
17920 Bind the web interface to the specified port.
17922 @item @code{bind-address} (default: @code{"127.0.0.1"})
17923 Bind the web interface to the specified address.
17925 @item @code{base} (default: @code{"/"})
17926 Specify the path of the base URL. This can be useful if
17927 @command{darkstat} is accessed via a reverse proxy.
17932 @subsubheading Prometheus Node Exporter Service
17934 @cindex prometheus-node-exporter
17935 The Prometheus ``node exporter'' makes hardware and operating system statistics
17936 provided by the Linux kernel available for the Prometheus monitoring system.
17937 This service should be deployed on all physical nodes and virtual machines,
17938 where monitoring these statistics is desirable.
17940 @defvar {Scheme variable} prometheus-node-exporter-service-type
17941 This is the service type for the
17942 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
17943 service, its value must be a @code{prometheus-node-exporter-configuration}
17944 record as in this example:
17947 (service prometheus-node-exporter-service-type
17948 (prometheus-node-exporter-configuration
17949 (web-listen-address ":9100")))
17953 @deftp {Data Type} prometheus-node-exporter-configuration
17954 Data type representing the configuration of @command{node_exporter}.
17957 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
17958 The prometheus-node-exporter package to use.
17960 @item @code{web-listen-address} (default: @code{":9100"})
17961 Bind the web interface to the specified address.
17966 @subsubheading Zabbix server
17967 @cindex zabbix zabbix-server
17968 Zabbix provides monitoring metrics, among others network utilization, CPU load
17969 and disk space consumption:
17972 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
17973 @item Auto-discovery of servers and network devices and interfaces.
17974 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
17975 @item Distributed monitoring with centralized web administration.
17976 @item Native high performance agents.
17977 @item SLA, and ITIL KPI metrics on reporting.
17978 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
17979 @item Remote command execution through Zabbix proxies.
17982 @c %start of fragment
17984 Available @code{zabbix-server-configuration} fields are:
17986 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
17987 The zabbix-server package.
17991 @deftypevr {@code{zabbix-server-configuration} parameter} string user
17992 User who will run the Zabbix server.
17994 Defaults to @samp{"zabbix"}.
17998 @deftypevr {@code{zabbix-server-configuration} parameter} group group
17999 Group who will run the Zabbix server.
18001 Defaults to @samp{"zabbix"}.
18005 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
18006 Database host name.
18008 Defaults to @samp{"127.0.0.1"}.
18012 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
18015 Defaults to @samp{"zabbix"}.
18019 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
18022 Defaults to @samp{"zabbix"}.
18026 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
18027 Database password. Please, use @code{include-files} with
18028 @code{DBPassword=SECRET} inside a specified file instead.
18030 Defaults to @samp{""}.
18034 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
18037 Defaults to @samp{5432}.
18041 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
18042 Specifies where log messages are written to:
18046 @code{system} - syslog.
18049 @code{file} - file specified with @code{log-file} parameter.
18052 @code{console} - standard output.
18056 Defaults to @samp{""}.
18060 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
18061 Log file name for @code{log-type} @code{file} parameter.
18063 Defaults to @samp{"/var/log/zabbix/server.log"}.
18067 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
18070 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
18074 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
18075 The location of certificate authority (CA) files for SSL server
18076 certificate verification.
18078 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
18082 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
18083 Location of SSL client certificates.
18085 Defaults to @samp{"/etc/ssl/certs"}.
18089 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
18090 Extra options will be appended to Zabbix server configuration file.
18092 Defaults to @samp{""}.
18096 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
18097 You may include individual files or all files in a directory in the
18098 configuration file.
18100 Defaults to @samp{()}.
18104 @c %end of fragment
18106 @subsubheading Zabbix agent
18107 @cindex zabbix zabbix-agent
18109 Zabbix agent gathers information for Zabbix server.
18111 @c %start of fragment
18113 Available @code{zabbix-agent-configuration} fields are:
18115 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
18116 The zabbix-agent package.
18120 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
18121 User who will run the Zabbix agent.
18123 Defaults to @samp{"zabbix"}.
18127 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
18128 Group who will run the Zabbix agent.
18130 Defaults to @samp{"zabbix"}.
18134 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
18135 Unique, case sensitive hostname which is required for active checks and
18136 must match hostname as configured on the server.
18138 Defaults to @samp{"Zabbix server"}.
18142 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
18143 Specifies where log messages are written to:
18147 @code{system} - syslog.
18150 @code{file} - file specified with @code{log-file} parameter.
18153 @code{console} - standard output.
18157 Defaults to @samp{""}.
18161 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
18162 Log file name for @code{log-type} @code{file} parameter.
18164 Defaults to @samp{"/var/log/zabbix/agent.log"}.
18168 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
18171 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
18175 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
18176 List of IP addresses, optionally in CIDR notation, or hostnames of
18177 Zabbix servers and Zabbix proxies. Incoming connections will be
18178 accepted only from the hosts listed here.
18180 Defaults to @samp{("127.0.0.1")}.
18184 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
18185 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
18186 proxies for active checks. If port is not specified, default port is
18187 used. If this parameter is not specified, active checks are disabled.
18189 Defaults to @samp{("127.0.0.1")}.
18193 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
18194 Extra options will be appended to Zabbix server configuration file.
18196 Defaults to @samp{""}.
18200 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
18201 You may include individual files or all files in a directory in the
18202 configuration file.
18204 Defaults to @samp{()}.
18208 @c %end of fragment
18210 @subsubheading Zabbix front-end
18211 @cindex zabbix zabbix-front-end
18213 This service provides a WEB interface to Zabbix server.
18215 @c %start of fragment
18217 Available @code{zabbix-front-end-configuration} fields are:
18219 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
18220 NGINX configuration.
18224 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
18225 Database host name.
18227 Defaults to @samp{"localhost"}.
18231 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
18234 Defaults to @samp{5432}.
18238 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
18241 Defaults to @samp{"zabbix"}.
18245 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
18248 Defaults to @samp{"zabbix"}.
18252 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
18253 Database password. Please, use @code{db-secret-file} instead.
18255 Defaults to @samp{""}.
18259 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
18260 Secret file which will be appended to @file{zabbix.conf.php} file. This
18261 file contains credentials for use by Zabbix front-end. You are expected
18262 to create it manually.
18264 Defaults to @samp{""}.
18268 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
18269 Zabbix server hostname.
18271 Defaults to @samp{"localhost"}.
18275 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
18276 Zabbix server port.
18278 Defaults to @samp{10051}.
18283 @c %end of fragment
18285 @node Kerberos Services
18286 @subsection Kerberos Services
18289 The @code{(gnu services kerberos)} module provides services relating to
18290 the authentication protocol @dfn{Kerberos}.
18292 @subsubheading Krb5 Service
18294 Programs using a Kerberos client library normally
18295 expect a configuration file in @file{/etc/krb5.conf}.
18296 This service generates such a file from a definition provided in the
18297 operating system declaration.
18298 It does not cause any daemon to be started.
18300 No ``keytab'' files are provided by this service---you must explicitly create them.
18301 This service is known to work with the MIT client library, @code{mit-krb5}.
18302 Other implementations have not been tested.
18304 @defvr {Scheme Variable} krb5-service-type
18305 A service type for Kerberos 5 clients.
18309 Here is an example of its use:
18311 (service krb5-service-type
18312 (krb5-configuration
18313 (default-realm "EXAMPLE.COM")
18314 (allow-weak-crypto? #t)
18317 (name "EXAMPLE.COM")
18318 (admin-server "groucho.example.com")
18319 (kdc "karl.example.com"))
18322 (admin-server "kerb-admin.argrx.edu")
18323 (kdc "keys.argrx.edu"))))))
18327 This example provides a Kerberos@tie{}5 client configuration which:
18329 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
18330 of which have distinct administration servers and key distribution centers;
18331 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
18332 specified by clients;
18333 @item Accepts services which only support encryption types known to be weak.
18336 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
18337 Only the most commonly used ones are described here.
18338 For a full list, and more detailed explanation of each, see the MIT
18339 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
18343 @deftp {Data Type} krb5-realm
18344 @cindex realm, kerberos
18347 This field is a string identifying the name of the realm.
18348 A common convention is to use the fully qualified DNS name of your organization,
18349 converted to upper case.
18351 @item @code{admin-server}
18352 This field is a string identifying the host where the administration server is
18356 This field is a string identifying the key distribution center
18361 @deftp {Data Type} krb5-configuration
18364 @item @code{allow-weak-crypto?} (default: @code{#f})
18365 If this flag is @code{#t} then services which only offer encryption algorithms
18366 known to be weak will be accepted.
18368 @item @code{default-realm} (default: @code{#f})
18369 This field should be a string identifying the default Kerberos
18370 realm for the client.
18371 You should set this field to the name of your Kerberos realm.
18372 If this value is @code{#f}
18373 then a realm must be specified with every Kerberos principal when invoking programs
18374 such as @command{kinit}.
18376 @item @code{realms}
18377 This should be a non-empty list of @code{krb5-realm} objects, which clients may
18379 Normally, one of them will have a @code{name} field matching the @code{default-realm}
18385 @subsubheading PAM krb5 Service
18388 The @code{pam-krb5} service allows for login authentication and password
18389 management via Kerberos.
18390 You will need this service if you want PAM enabled applications to authenticate
18391 users using Kerberos.
18393 @defvr {Scheme Variable} pam-krb5-service-type
18394 A service type for the Kerberos 5 PAM module.
18397 @deftp {Data Type} pam-krb5-configuration
18398 Data type representing the configuration of the Kerberos 5 PAM module.
18399 This type has the following parameters:
18401 @item @code{pam-krb5} (default: @code{pam-krb5})
18402 The pam-krb5 package to use.
18404 @item @code{minimum-uid} (default: @code{1000})
18405 The smallest user ID for which Kerberos authentications should be attempted.
18406 Local accounts with lower values will silently fail to authenticate.
18411 @node LDAP Services
18412 @subsection LDAP Services
18414 @cindex nslcd, LDAP service
18416 The @code{(gnu services authentication)} module provides the
18417 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
18418 server. In addition to configuring the service itself, you may want to add
18419 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
18420 Switch} for detailed information.
18422 Here is a simple operating system declaration with a default configuration of
18423 the @code{nslcd-service-type} and a Name Service Switch configuration that
18424 consults the @code{ldap} name service last:
18427 (use-service-modules authentication)
18428 (use-modules (gnu system nss))
18434 (service nslcd-service-type)
18435 (service dhcp-client-service-type)
18437 (name-service-switch
18438 (let ((services (list (name-service (name "db"))
18439 (name-service (name "files"))
18440 (name-service (name "ldap")))))
18441 (name-service-switch
18442 (inherit %mdns-host-lookup-nss)
18443 (password services)
18446 (netgroup services)
18447 (gshadow services)))))
18450 @c %start of generated documentation for nslcd-configuration
18452 Available @code{nslcd-configuration} fields are:
18454 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
18455 The @code{nss-pam-ldapd} package to use.
18459 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
18460 The number of threads to start that can handle requests and perform LDAP
18461 queries. Each thread opens a separate connection to the LDAP server.
18462 The default is to start 5 threads.
18464 Defaults to @samp{disabled}.
18468 @deftypevr {@code{nslcd-configuration} parameter} string uid
18469 This specifies the user id with which the daemon should be run.
18471 Defaults to @samp{"nslcd"}.
18475 @deftypevr {@code{nslcd-configuration} parameter} string gid
18476 This specifies the group id with which the daemon should be run.
18478 Defaults to @samp{"nslcd"}.
18482 @deftypevr {@code{nslcd-configuration} parameter} log-option log
18483 This option controls the way logging is done via a list containing
18484 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
18485 or "syslog", or an absolute file name. The LEVEL argument is optional
18486 and specifies the log level. The log level may be one of the following
18487 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
18488 messages with the specified log level or higher are logged.
18490 Defaults to @samp{("/var/log/nslcd" info)}.
18494 @deftypevr {@code{nslcd-configuration} parameter} list uri
18495 The list of LDAP server URIs. Normally, only the first server will be
18496 used with the following servers as fall-back.
18498 Defaults to @samp{("ldap://localhost:389/")}.
18502 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
18503 The version of the LDAP protocol to use. The default is to use the
18504 maximum version supported by the LDAP library.
18506 Defaults to @samp{disabled}.
18510 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
18511 Specifies the distinguished name with which to bind to the directory
18512 server for lookups. The default is to bind anonymously.
18514 Defaults to @samp{disabled}.
18518 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
18519 Specifies the credentials with which to bind. This option is only
18520 applicable when used with binddn.
18522 Defaults to @samp{disabled}.
18526 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
18527 Specifies the distinguished name to use when the root user tries to
18528 modify a user's password using the PAM module.
18530 Defaults to @samp{disabled}.
18534 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
18535 Specifies the credentials with which to bind if the root user tries to
18536 change a user's password. This option is only applicable when used with
18539 Defaults to @samp{disabled}.
18543 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
18544 Specifies the SASL mechanism to be used when performing SASL
18547 Defaults to @samp{disabled}.
18551 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
18552 Specifies the SASL realm to be used when performing SASL authentication.
18554 Defaults to @samp{disabled}.
18558 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
18559 Specifies the authentication identity to be used when performing SASL
18562 Defaults to @samp{disabled}.
18566 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
18567 Specifies the authorization identity to be used when performing SASL
18570 Defaults to @samp{disabled}.
18574 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
18575 Determines whether the LDAP server host name should be canonicalised. If
18576 this is enabled the LDAP library will do a reverse host name lookup. By
18577 default, it is left up to the LDAP library whether this check is
18580 Defaults to @samp{disabled}.
18584 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
18585 Set the name for the GSS-API Kerberos credentials cache.
18587 Defaults to @samp{disabled}.
18591 @deftypevr {@code{nslcd-configuration} parameter} string base
18592 The directory search base.
18594 Defaults to @samp{"dc=example,dc=com"}.
18598 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
18599 Specifies the search scope (subtree, onelevel, base or children). The
18600 default scope is subtree; base scope is almost never useful for name
18601 service lookups; children scope is not supported on all servers.
18603 Defaults to @samp{(subtree)}.
18607 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
18608 Specifies the policy for dereferencing aliases. The default policy is
18609 to never dereference aliases.
18611 Defaults to @samp{disabled}.
18615 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
18616 Specifies whether automatic referral chasing should be enabled. The
18617 default behaviour is to chase referrals.
18619 Defaults to @samp{disabled}.
18623 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
18624 This option allows for custom attributes to be looked up instead of the
18625 default RFC 2307 attributes. It is a list of maps, each consisting of
18626 the name of a map, the RFC 2307 attribute to match and the query
18627 expression for the attribute as it is available in the directory.
18629 Defaults to @samp{()}.
18633 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
18634 A list of filters consisting of the name of a map to which the filter
18635 applies and an LDAP search filter expression.
18637 Defaults to @samp{()}.
18641 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
18642 Specifies the time limit in seconds to use when connecting to the
18643 directory server. The default value is 10 seconds.
18645 Defaults to @samp{disabled}.
18649 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
18650 Specifies the time limit (in seconds) to wait for a response from the
18651 LDAP server. A value of zero, which is the default, is to wait
18652 indefinitely for searches to be completed.
18654 Defaults to @samp{disabled}.
18658 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
18659 Specifies the period if inactivity (in seconds) after which the con‐
18660 nection to the LDAP server will be closed. The default is not to time
18663 Defaults to @samp{disabled}.
18667 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
18668 Specifies the number of seconds to sleep when connecting to all LDAP
18669 servers fails. By default one second is waited between the first
18670 failure and the first retry.
18672 Defaults to @samp{disabled}.
18676 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
18677 Specifies the time after which the LDAP server is considered to be
18678 permanently unavailable. Once this time is reached retries will be done
18679 only once per this time period. The default value is 10 seconds.
18681 Defaults to @samp{disabled}.
18685 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
18686 Specifies whether to use SSL/TLS or not (the default is not to). If
18687 'start-tls is specified then StartTLS is used rather than raw LDAP over
18690 Defaults to @samp{disabled}.
18694 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
18695 Specifies what checks to perform on a server-supplied certificate. The
18696 meaning of the values is described in the ldap.conf(5) manual page.
18698 Defaults to @samp{disabled}.
18702 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
18703 Specifies the directory containing X.509 certificates for peer authen‐
18704 tication. This parameter is ignored when using GnuTLS.
18706 Defaults to @samp{disabled}.
18710 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
18711 Specifies the path to the X.509 certificate for peer authentication.
18713 Defaults to @samp{disabled}.
18717 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
18718 Specifies the path to an entropy source. This parameter is ignored when
18721 Defaults to @samp{disabled}.
18725 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
18726 Specifies the ciphers to use for TLS as a string.
18728 Defaults to @samp{disabled}.
18732 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
18733 Specifies the path to the file containing the local certificate for
18734 client TLS authentication.
18736 Defaults to @samp{disabled}.
18740 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
18741 Specifies the path to the file containing the private key for client TLS
18744 Defaults to @samp{disabled}.
18748 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
18749 Set this to a number greater than 0 to request paged results from the
18750 LDAP server in accordance with RFC2696. The default (0) is to not
18751 request paged results.
18753 Defaults to @samp{disabled}.
18757 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
18758 This option prevents group membership lookups through LDAP for the
18759 specified users. Alternatively, the value 'all-local may be used. With
18760 that value nslcd builds a full list of non-LDAP users on startup.
18762 Defaults to @samp{disabled}.
18766 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
18767 This option ensures that LDAP users with a numeric user id lower than
18768 the specified value are ignored.
18770 Defaults to @samp{disabled}.
18774 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
18775 This option specifies an offset that is added to all LDAP numeric user
18776 ids. This can be used to avoid user id collisions with local users.
18778 Defaults to @samp{disabled}.
18782 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
18783 This option specifies an offset that is added to all LDAP numeric group
18784 ids. This can be used to avoid user id collisions with local groups.
18786 Defaults to @samp{disabled}.
18790 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
18791 If this option is set, the member attribute of a group may point to
18792 another group. Members of nested groups are also returned in the higher
18793 level group and parent groups are returned when finding groups for a
18794 specific user. The default is not to perform extra searches for nested
18797 Defaults to @samp{disabled}.
18801 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
18802 If this option is set, the group member list is not retrieved when
18803 looking up groups. Lookups for finding which groups a user belongs to
18804 will remain functional so the user will likely still get the correct
18805 groups assigned on login.
18807 Defaults to @samp{disabled}.
18811 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
18812 If this option is set, functions which cause all user/group entries to
18813 be loaded from the directory will not succeed in doing so. This can
18814 dramatically reduce LDAP server load in situations where there are a
18815 great number of users and/or groups. This option is not recommended for
18816 most configurations.
18818 Defaults to @samp{disabled}.
18822 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
18823 This option can be used to specify how user and group names are verified
18824 within the system. This pattern is used to check all user and group
18825 names that are requested and returned from LDAP.
18827 Defaults to @samp{disabled}.
18831 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
18832 This specifies whether or not to perform searches using case-insensitive
18833 matching. Enabling this could open up the system to authorization
18834 bypass vulnerabilities and introduce nscd cache poisoning
18835 vulnerabilities which allow denial of service.
18837 Defaults to @samp{disabled}.
18841 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
18842 This option specifies whether password policy controls are requested and
18843 handled from the LDAP server when performing user authentication.
18845 Defaults to @samp{disabled}.
18849 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
18850 By default nslcd performs an LDAP search with the user's credentials
18851 after BIND (authentication) to ensure that the BIND operation was
18852 successful. The default search is a simple check to see if the user's
18853 DN exists. A search filter can be specified that will be used instead.
18854 It should return at least one entry.
18856 Defaults to @samp{disabled}.
18860 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
18861 This option allows flexible fine tuning of the authorisation check that
18862 should be performed. The search filter specified is executed and if any
18863 entries match, access is granted, otherwise access is denied.
18865 Defaults to @samp{disabled}.
18869 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
18870 If this option is set password modification using pam_ldap will be
18871 denied and the specified message will be presented to the user instead.
18872 The message can be used to direct the user to an alternative means of
18873 changing their password.
18875 Defaults to @samp{disabled}.
18879 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
18880 List of pam service names for which LDAP authentication should suffice.
18882 Defaults to @samp{()}.
18886 @c %end of generated documentation for nslcd-configuration
18890 @subsection Web Services
18895 The @code{(gnu services web)} module provides the Apache HTTP Server,
18896 the nginx web server, and also a fastcgi wrapper daemon.
18898 @subsubheading Apache HTTP Server
18900 @deffn {Scheme Variable} httpd-service-type
18901 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
18902 (@dfn{httpd}). The value for this service type is a
18903 @code{httpd-configuration} record.
18905 A simple example configuration is given below.
18908 (service httpd-service-type
18909 (httpd-configuration
18912 (server-name "www.example.com")
18913 (document-root "/srv/http/www.example.com")))))
18916 Other services can also extend the @code{httpd-service-type} to add to
18920 (simple-service 'my-extra-server httpd-service-type
18924 (list (string-append
18925 "ServerName "www.example.com
18926 DocumentRoot \"/srv/http/www.example.com\"")))))
18930 The details for the @code{httpd-configuration}, @code{httpd-module},
18931 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
18934 @deffn {Data Type} httpd-configuration
18935 This data type represents the configuration for the httpd service.
18938 @item @code{package} (default: @code{httpd})
18939 The httpd package to use.
18941 @item @code{pid-file} (default: @code{"/var/run/httpd"})
18942 The pid file used by the shepherd-service.
18944 @item @code{config} (default: @code{(httpd-config-file)})
18945 The configuration file to use with the httpd service. The default value
18946 is a @code{httpd-config-file} record, but this can also be a different
18947 G-expression that generates a file, for example a @code{plain-file}. A
18948 file outside of the store can also be specified through a string.
18953 @deffn {Data Type} httpd-module
18954 This data type represents a module for the httpd service.
18958 The name of the module.
18961 The file for the module. This can be relative to the httpd package being
18962 used, the absolute location of a file, or a G-expression for a file
18963 within the store, for example @code{(file-append mod-wsgi
18964 "/modules/mod_wsgi.so")}.
18969 @defvr {Scheme Variable} %default-httpd-modules
18970 A default list of @code{httpd-module} objects.
18973 @deffn {Data Type} httpd-config-file
18974 This data type represents a configuration file for the httpd service.
18977 @item @code{modules} (default: @code{%default-httpd-modules})
18978 The modules to load. Additional modules can be added here, or loaded by
18979 additional configuration.
18981 For example, in order to handle requests for PHP files, you can use Apache’s
18982 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
18985 (service httpd-service-type
18986 (httpd-configuration
18991 (name "proxy_module")
18992 (file "modules/mod_proxy.so"))
18994 (name "proxy_fcgi_module")
18995 (file "modules/mod_proxy_fcgi.so"))
18996 %default-httpd-modules))
18997 (extra-config (list "\
18998 <FilesMatch \\.php$>
18999 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
19000 </FilesMatch>"))))))
19001 (service php-fpm-service-type
19002 (php-fpm-configuration
19003 (socket "/var/run/php-fpm.sock")
19004 (socket-group "httpd")))
19007 @item @code{server-root} (default: @code{httpd})
19008 The @code{ServerRoot} in the configuration file, defaults to the httpd
19009 package. Directives including @code{Include} and @code{LoadModule} are
19010 taken as relative to the server root.
19012 @item @code{server-name} (default: @code{#f})
19013 The @code{ServerName} in the configuration file, used to specify the
19014 request scheme, hostname and port that the server uses to identify
19017 This doesn't need to be set in the server config, and can be specifyed
19018 in virtual hosts. The default is @code{#f} to not specify a
19021 @item @code{document-root} (default: @code{"/srv/http"})
19022 The @code{DocumentRoot} from which files will be served.
19024 @item @code{listen} (default: @code{'("80")})
19025 The list of values for the @code{Listen} directives in the config
19026 file. The value should be a list of strings, when each string can
19027 specify the port number to listen on, and optionally the IP address and
19030 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19031 The @code{PidFile} to use. This should match the @code{pid-file} set in
19032 the @code{httpd-configuration} so that the Shepherd service is
19033 configured correctly.
19035 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
19036 The @code{ErrorLog} to which the server will log errors.
19038 @item @code{user} (default: @code{"httpd"})
19039 The @code{User} which the server will answer requests as.
19041 @item @code{group} (default: @code{"httpd"})
19042 The @code{Group} which the server will answer requests as.
19044 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
19045 A flat list of strings and G-expressions which will be added to the end
19046 of the configuration file.
19048 Any values which the service is extended with will be appended to this
19054 @deffn {Data Type} httpd-virtualhost
19055 This data type represents a virtualhost configuration block for the httpd service.
19057 These should be added to the extra-config for the httpd-service.
19060 (simple-service 'my-extra-server httpd-service-type
19064 (list (string-append
19065 "ServerName "www.example.com
19066 DocumentRoot \"/srv/http/www.example.com\"")))))
19070 @item @code{addresses-and-ports}
19071 The addresses and ports for the @code{VirtualHost} directive.
19073 @item @code{contents}
19074 The contents of the @code{VirtualHost} directive, this should be a list
19075 of strings and G-expressions.
19080 @subsubheading NGINX
19082 @deffn {Scheme Variable} nginx-service-type
19083 Service type for the @uref{https://nginx.org/,NGinx} web server. The
19084 value for this service type is a @code{<nginx-configuration>} record.
19086 A simple example configuration is given below.
19089 (service nginx-service-type
19090 (nginx-configuration
19092 (list (nginx-server-configuration
19093 (server-name '("www.example.com"))
19094 (root "/srv/http/www.example.com"))))))
19097 In addition to adding server blocks to the service configuration
19098 directly, this service can be extended by other services to add server
19099 blocks, as in this example:
19102 (simple-service 'my-extra-server nginx-service-type
19103 (list (nginx-server-configuration
19104 (root "/srv/http/extra-website")
19105 (try-files (list "$uri" "$uri/index.html")))))
19109 At startup, @command{nginx} has not yet read its configuration file, so
19110 it uses a default file to log error messages. If it fails to load its
19111 configuration file, that is where error messages are logged. After the
19112 configuration file is loaded, the default error log file changes as per
19113 configuration. In our case, startup error messages can be found in
19114 @file{/var/run/nginx/logs/error.log}, and after configuration in
19115 @file{/var/log/nginx/error.log}. The second location can be changed
19116 with the @var{log-directory} configuration option.
19118 @deffn {Data Type} nginx-configuration
19119 This data type represents the configuration for NGinx. Some
19120 configuration can be done through this and the other provided record
19121 types, or alternatively, a config file can be provided.
19124 @item @code{nginx} (default: @code{nginx})
19125 The nginx package to use.
19127 @item @code{log-directory} (default: @code{"/var/log/nginx"})
19128 The directory to which NGinx will write log files.
19130 @item @code{run-directory} (default: @code{"/var/run/nginx"})
19131 The directory in which NGinx will create a pid file, and write temporary
19134 @item @code{server-blocks} (default: @code{'()})
19135 A list of @dfn{server blocks} to create in the generated configuration
19136 file, the elements should be of type
19137 @code{<nginx-server-configuration>}.
19139 The following example would setup NGinx to serve @code{www.example.com}
19140 from the @code{/srv/http/www.example.com} directory, without using
19143 (service nginx-service-type
19144 (nginx-configuration
19146 (list (nginx-server-configuration
19147 (server-name '("www.example.com"))
19148 (root "/srv/http/www.example.com"))))))
19151 @item @code{upstream-blocks} (default: @code{'()})
19152 A list of @dfn{upstream blocks} to create in the generated configuration
19153 file, the elements should be of type
19154 @code{<nginx-upstream-configuration>}.
19156 Configuring upstreams through the @code{upstream-blocks} can be useful
19157 when combined with @code{locations} in the
19158 @code{<nginx-server-configuration>} records. The following example
19159 creates a server configuration with one location configuration, that
19160 will proxy requests to a upstream configuration, which will handle
19161 requests with two servers.
19166 (nginx-configuration
19168 (list (nginx-server-configuration
19169 (server-name '("www.example.com"))
19170 (root "/srv/http/www.example.com")
19173 (nginx-location-configuration
19175 (body '("proxy_pass http://server-proxy;"))))))))
19177 (list (nginx-upstream-configuration
19178 (name "server-proxy")
19179 (servers (list "server1.example.com"
19180 "server2.example.com")))))))
19183 @item @code{file} (default: @code{#f})
19184 If a configuration @var{file} is provided, this will be used, rather than
19185 generating a configuration file from the provided @code{log-directory},
19186 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
19187 proper operation, these arguments should match what is in @var{file} to ensure
19188 that the directories are created when the service is activated.
19190 This can be useful if you have an existing configuration file, or it's
19191 not possible to do what is required through the other parts of the
19192 nginx-configuration record.
19194 @item @code{server-names-hash-bucket-size} (default: @code{#f})
19195 Bucket size for the server names hash tables, defaults to @code{#f} to
19196 use the size of the processors cache line.
19198 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
19199 Maximum bucket size for the server names hash tables.
19201 @item @code{extra-content} (default: @code{""})
19202 Extra content for the @code{http} block. Should be string or a string
19203 valued G-expression.
19208 @deftp {Data Type} nginx-server-configuration
19209 Data type representing the configuration of an nginx server block.
19210 This type has the following parameters:
19213 @item @code{listen} (default: @code{'("80" "443 ssl")})
19214 Each @code{listen} directive sets the address and port for IP, or the
19215 path for a UNIX-domain socket on which the server will accept requests.
19216 Both address and port, or only address or only port can be specified.
19217 An address may also be a hostname, for example:
19220 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
19223 @item @code{server-name} (default: @code{(list 'default)})
19224 A list of server names this server represents. @code{'default} represents the
19225 default server for connections matching no other server.
19227 @item @code{root} (default: @code{"/srv/http"})
19228 Root of the website nginx will serve.
19230 @item @code{locations} (default: @code{'()})
19231 A list of @dfn{nginx-location-configuration} or
19232 @dfn{nginx-named-location-configuration} records to use within this
19235 @item @code{index} (default: @code{(list "index.html")})
19236 Index files to look for when clients ask for a directory. If it cannot be found,
19237 Nginx will send the list of files in the directory.
19239 @item @code{try-files} (default: @code{'()})
19240 A list of files whose existence is checked in the specified order.
19241 @code{nginx} will use the first file it finds to process the request.
19243 @item @code{ssl-certificate} (default: @code{#f})
19244 Where to find the certificate for secure connections. Set it to @code{#f} if
19245 you don't have a certificate or you don't want to use HTTPS.
19247 @item @code{ssl-certificate-key} (default: @code{#f})
19248 Where to find the private key for secure connections. Set it to @code{#f} if
19249 you don't have a key or you don't want to use HTTPS.
19251 @item @code{server-tokens?} (default: @code{#f})
19252 Whether the server should add its configuration to response.
19254 @item @code{raw-content} (default: @code{'()})
19255 A list of raw lines added to the server block.
19260 @deftp {Data Type} nginx-upstream-configuration
19261 Data type representing the configuration of an nginx @code{upstream}
19262 block. This type has the following parameters:
19266 Name for this group of servers.
19268 @item @code{servers}
19269 Specify the addresses of the servers in the group. The address can be
19270 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
19271 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
19272 prefix @samp{unix:}. For addresses using an IP address or domain name,
19273 the default port is 80, and a different port can be specified
19279 @deftp {Data Type} nginx-location-configuration
19280 Data type representing the configuration of an nginx @code{location}
19281 block. This type has the following parameters:
19285 URI which this location block matches.
19287 @anchor{nginx-location-configuration body}
19289 Body of the location block, specified as a list of strings. This can contain
19291 configuration directives. For example, to pass requests to a upstream
19292 server group defined using an @code{nginx-upstream-configuration} block,
19293 the following directive would be specified in the body @samp{(list "proxy_pass
19294 http://upstream-name;")}.
19299 @deftp {Data Type} nginx-named-location-configuration
19300 Data type representing the configuration of an nginx named location
19301 block. Named location blocks are used for request redirection, and not
19302 used for regular request processing. This type has the following
19307 Name to identify this location block.
19310 @xref{nginx-location-configuration body}, as the body for named location
19311 blocks can be used in a similar way to the
19312 @code{nginx-location-configuration body}. One restriction is that the
19313 body of a named location block cannot contain location blocks.
19318 @subsubheading Varnish Cache
19320 Varnish is a fast cache server that sits in between web applications
19321 and end users. It proxies requests from clients and caches the
19322 accessed URLs such that multiple requests for the same resource only
19323 creates one request to the back-end.
19325 @defvr {Scheme Variable} varnish-service-type
19326 Service type for the Varnish daemon.
19329 @deftp {Data Type} varnish-configuration
19330 Data type representing the @code{varnish} service configuration.
19331 This type has the following parameters:
19334 @item @code{package} (default: @code{varnish})
19335 The Varnish package to use.
19337 @item @code{name} (default: @code{"default"})
19338 A name for this Varnish instance. Varnish will create a directory in
19339 @file{/var/varnish/} with this name and keep temporary files there. If
19340 the name starts with a forward slash, it is interpreted as an absolute
19343 Pass the @code{-n} argument to other Varnish programs to connect to the
19344 named instance, e.g.@: @command{varnishncsa -n default}.
19346 @item @code{backend} (default: @code{"localhost:8080"})
19347 The backend to use. This option has no effect if @code{vcl} is set.
19349 @item @code{vcl} (default: #f)
19350 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
19351 is @code{#f}, Varnish will proxy @code{backend} using the default
19352 configuration. Otherwise this must be a file-like object with valid
19355 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
19356 For example, to mirror @url{http://www.gnu.org,www.gnu.org} with VCL you
19357 can do something along these lines:
19360 (define %gnu-mirror
19364 backend gnu @{ .host = "www.gnu.org"; @}"))
19368 (services (cons (service varnish-service-type
19369 (varnish-configuration
19371 (vcl %gnu-mirror)))
19375 The configuration of an already running Varnish instance can be inspected
19376 and changed using the @command{varnishadm} program.
19378 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
19379 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
19380 comprehensive documentation on Varnish and its configuration language.
19382 @item @code{listen} (default: @code{'("localhost:80")})
19383 List of addresses Varnish will listen on.
19385 @item @code{storage} (default: @code{'("malloc,128m")})
19386 List of storage backends that will be available in VCL.
19388 @item @code{parameters} (default: @code{'()})
19389 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
19391 @item @code{extra-options} (default: @code{'()})
19392 Additional arguments to pass to the @command{varnishd} process.
19397 @subsubheading Patchwork
19399 Patchwork is a patch tracking system. It can collect patches sent to a
19400 mailing list, and display them in a web interface.
19402 @defvr {Scheme Variable} patchwork-service-type
19403 Service type for Patchwork.
19406 The following example is an example of a minimal service for Patchwork, for
19407 the @code{patchwork.example.com} domain.
19410 (service patchwork-service-type
19411 (patchwork-configuration
19412 (domain "patchwork.example.com")
19414 (patchwork-settings-module
19415 (allowed-hosts (list domain))
19416 (default-from-email "patchwork@@patchwork.example.com")))
19417 (getmail-retriever-config
19418 (getmail-retriever-configuration
19419 (type "SimpleIMAPSSLRetriever")
19420 (server "imap.example.com")
19422 (username "patchwork")
19424 (list (file-append coreutils "/bin/cat")
19425 "/etc/getmail-patchwork-imap-password"))
19427 '((mailboxes . ("Patches"))))))))
19431 There are three records for configuring the Patchwork service. The
19432 @code{<patchwork-configuration>} relates to the configuration for Patchwork
19433 within the HTTPD service.
19435 The @code{settings-module} field within the @code{<patchwork-configuration>}
19436 record can be populated with the @code{<patchwork-settings-module>} record,
19437 which describes a settings module that is generated within the Guix store.
19439 For the @code{database-configuration} field within the
19440 @code{<patchwork-settings-module>}, the
19441 @code{<patchwork-database-configuration>} must be used.
19443 @deftp {Data Type} patchwork-configuration
19444 Data type representing the Patchwork service configuration. This type has the
19445 following parameters:
19448 @item @code{patchwork} (default: @code{patchwork})
19449 The Patchwork package to use.
19451 @item @code{domain}
19452 The domain to use for Patchwork, this is used in the HTTPD service virtual
19455 @item @code{settings-module}
19456 The settings module to use for Patchwork. As a Django application, Patchwork
19457 is configured with a Python module containing the settings. This can either be
19458 an instance of the @code{<patchwork-settings-module>} record, any other record
19459 that represents the settings in the store, or a directory outside of the
19462 @item @code{static-path} (default: @code{"/static/"})
19463 The path under which the HTTPD service should serve the static files.
19465 @item @code{getmail-retriever-config}
19466 The getmail-retriever-configuration record value to use with
19467 Patchwork. Getmail will be configured with this value, the messages will be
19468 delivered to Patchwork.
19473 @deftp {Data Type} patchwork-settings-module
19474 Data type representing a settings module for Patchwork. Some of these
19475 settings relate directly to Patchwork, but others relate to Django, the web
19476 framework used by Patchwork, or the Django Rest Framework library. This type
19477 has the following parameters:
19480 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
19481 The database connection settings used for Patchwork. See the
19482 @code{<patchwork-database-configuration>} record type for more information.
19484 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
19485 Patchwork, as a Django web application uses a secret key for cryptographically
19486 signing values. This file should contain a unique unpredictable value.
19488 If this file does not exist, it will be created and populated with a random
19489 value by the patchwork-setup shepherd service.
19491 This setting relates to Django.
19493 @item @code{allowed-hosts}
19494 A list of valid hosts for this Patchwork service. This should at least include
19495 the domain specified in the @code{<patchwork-configuration>} record.
19497 This is a Django setting.
19499 @item @code{default-from-email}
19500 The email address from which Patchwork should send email by default.
19502 This is a Patchwork setting.
19504 @item @code{static-url} (default: @code{#f})
19505 The URL to use when serving static assets. It can be part of a URL, or a full
19506 URL, but must end in a @code{/}.
19508 If the default value is used, the @code{static-path} value from the
19509 @code{<patchwork-configuration>} record will be used.
19511 This is a Django setting.
19513 @item @code{admins} (default: @code{'()})
19514 Email addresses to send the details of errors that occur. Each value should
19515 be a list containing two elements, the name and then the email address.
19517 This is a Django setting.
19519 @item @code{debug?} (default: @code{#f})
19520 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
19521 messages will be shown.
19523 This is a Django setting.
19525 @item @code{enable-rest-api?} (default: @code{#t})
19526 Whether to enable the Patchwork REST API.
19528 This is a Patchwork setting.
19530 @item @code{enable-xmlrpc?} (default: @code{#t})
19531 Whether to enable the XML RPC API.
19533 This is a Patchwork setting.
19535 @item @code{force-https-links?} (default: @code{#t})
19536 Whether to use HTTPS links on Patchwork pages.
19538 This is a Patchwork setting.
19540 @item @code{extra-settings} (default: @code{""})
19541 Extra code to place at the end of the Patchwork settings module.
19546 @deftp {Data Type} patchwork-database-configuration
19547 Data type representing the database configuration for Patchwork.
19550 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
19551 The database engine to use.
19553 @item @code{name} (default: @code{"patchwork"})
19554 The name of the database to use.
19556 @item @code{user} (default: @code{"httpd"})
19557 The user to connect to the database as.
19559 @item @code{password} (default: @code{""})
19560 The password to use when connecting to the database.
19562 @item @code{host} (default: @code{""})
19563 The host to make the database connection to.
19565 @item @code{port} (default: @code{""})
19566 The port on which to connect to the database.
19571 @subsubheading FastCGI
19574 FastCGI is an interface between the front-end and the back-end of a web
19575 service. It is a somewhat legacy facility; new web services should
19576 generally just talk HTTP between the front-end and the back-end.
19577 However there are a number of back-end services such as PHP or the
19578 optimized HTTP Git repository access that use FastCGI, so we have
19579 support for it in Guix.
19581 To use FastCGI, you configure the front-end web server (e.g., nginx) to
19582 dispatch some subset of its requests to the fastcgi backend, which
19583 listens on a local TCP or UNIX socket. There is an intermediary
19584 @code{fcgiwrap} program that sits between the actual backend process and
19585 the web server. The front-end indicates which backend program to run,
19586 passing that information to the @code{fcgiwrap} process.
19588 @defvr {Scheme Variable} fcgiwrap-service-type
19589 A service type for the @code{fcgiwrap} FastCGI proxy.
19592 @deftp {Data Type} fcgiwrap-configuration
19593 Data type representing the configuration of the @code{fcgiwrap} service.
19594 This type has the following parameters:
19596 @item @code{package} (default: @code{fcgiwrap})
19597 The fcgiwrap package to use.
19599 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
19600 The socket on which the @code{fcgiwrap} process should listen, as a
19601 string. Valid @var{socket} values include
19602 @code{unix:@var{/path/to/unix/socket}},
19603 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
19604 @code{tcp6:[@var{ipv6_addr}]:port}.
19606 @item @code{user} (default: @code{fcgiwrap})
19607 @itemx @code{group} (default: @code{fcgiwrap})
19608 The user and group names, as strings, under which to run the
19609 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
19610 the user asks for the specific user or group names @code{fcgiwrap} that
19611 the corresponding user and/or group is present on the system.
19613 It is possible to configure a FastCGI-backed web service to pass HTTP
19614 authentication information from the front-end to the back-end, and to
19615 allow @code{fcgiwrap} to run the back-end process as a corresponding
19616 local user. To enable this capability on the back-end., run
19617 @code{fcgiwrap} as the @code{root} user and group. Note that this
19618 capability also has to be configured on the front-end as well.
19623 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
19624 with some additional features useful for sites of any size.
19626 These features include:
19628 @item Adaptive process spawning
19629 @item Basic statistics (similar to Apache's mod_status)
19630 @item Advanced process management with graceful stop/start
19631 @item Ability to start workers with different uid/gid/chroot/environment
19632 and different php.ini (replaces safe_mode)
19633 @item Stdout & stderr logging
19634 @item Emergency restart in case of accidental opcode cache destruction
19635 @item Accelerated upload support
19636 @item Support for a "slowlog"
19637 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
19638 a special function to finish request & flush all data while continuing to do
19639 something time-consuming (video converting, stats processing, etc.)
19641 ...@: and much more.
19643 @defvr {Scheme Variable} php-fpm-service-type
19644 A Service type for @code{php-fpm}.
19647 @deftp {Data Type} php-fpm-configuration
19648 Data Type for php-fpm service configuration.
19650 @item @code{php} (default: @code{php})
19651 The php package to use.
19652 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
19653 The address on which to accept FastCGI requests. Valid syntaxes are:
19655 @item @code{"ip.add.re.ss:port"}
19656 Listen on a TCP socket to a specific address on a specific port.
19657 @item @code{"port"}
19658 Listen on a TCP socket to all addresses on a specific port.
19659 @item @code{"/path/to/unix/socket"}
19660 Listen on a unix socket.
19663 @item @code{user} (default: @code{php-fpm})
19664 User who will own the php worker processes.
19665 @item @code{group} (default: @code{php-fpm})
19666 Group of the worker processes.
19667 @item @code{socket-user} (default: @code{php-fpm})
19668 User who can speak to the php-fpm socket.
19669 @item @code{socket-group} (default: @code{php-fpm})
19670 Group that can speak to the php-fpm socket.
19671 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
19672 The process id of the php-fpm process is written to this file
19673 once the service has started.
19674 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
19675 Log for the php-fpm master process.
19676 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
19677 Detailed settings for the php-fpm process manager.
19680 @item @code{<php-fpm-dynamic-process-manager-configuration>}
19681 @item @code{<php-fpm-static-process-manager-configuration>}
19682 @item @code{<php-fpm-on-demand-process-manager-configuration>}
19684 @item @code{display-errors} (default @code{#f})
19685 Determines whether php errors and warning should be sent to clients
19686 and displayed in their browsers.
19687 This is useful for local php development, but a security risk for public sites,
19688 as error messages can reveal passwords and personal data.
19689 @item @code{timezone} (default @code{#f})
19690 Specifies @code{php_admin_value[date.timezone]} parameter.
19691 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
19692 This file will log the @code{stderr} outputs of php worker processes.
19693 Can be set to @code{#f} to disable logging.
19694 @item @code{file} (default @code{#f})
19695 An optional override of the whole configuration.
19696 You can use the @code{mixed-text-file} function or an absolute filepath for it.
19700 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
19701 Data Type for the @code{dynamic} php-fpm process manager. With the
19702 @code{dynamic} process manager, spare worker processes are kept around
19703 based on it's configured limits.
19705 @item @code{max-children} (default: @code{5})
19706 Maximum of worker processes.
19707 @item @code{start-servers} (default: @code{2})
19708 How many worker processes should be started on start-up.
19709 @item @code{min-spare-servers} (default: @code{1})
19710 How many spare worker processes should be kept around at minimum.
19711 @item @code{max-spare-servers} (default: @code{3})
19712 How many spare worker processes should be kept around at maximum.
19716 @deftp {Data type} php-fpm-static-process-manager-configuration
19717 Data Type for the @code{static} php-fpm process manager. With the
19718 @code{static} process manager, an unchanging number of worker processes
19721 @item @code{max-children} (default: @code{5})
19722 Maximum of worker processes.
19726 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
19727 Data Type for the @code{on-demand} php-fpm process manager. With the
19728 @code{on-demand} process manager, worker processes are only created as
19731 @item @code{max-children} (default: @code{5})
19732 Maximum of worker processes.
19733 @item @code{process-idle-timeout} (default: @code{10})
19734 The time in seconds after which a process with no requests is killed.
19739 @deffn {Scheme Procedure} nginx-php-fpm-location @
19740 [#:nginx-package nginx] @
19741 [socket (string-append "/var/run/php" @
19742 (version-major (package-version php)) @
19744 A helper function to quickly add php to an @code{nginx-server-configuration}.
19747 A simple services setup for nginx with php can look like this:
19749 (services (cons* (service dhcp-client-service-type)
19750 (service php-fpm-service-type)
19751 (service nginx-service-type
19752 (nginx-server-configuration
19753 (server-name '("example.com"))
19754 (root "/srv/http/")
19756 (list (nginx-php-location)))
19758 (ssl-certificate #f)
19759 (ssl-certificate-key #f)))
19763 @cindex cat-avatar-generator
19764 The cat avatar generator is a simple service to demonstrate the use of php-fpm
19765 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
19766 the hash of a user's email address.
19768 @deffn {Scheme Procedure} cat-avatar-generator-service @
19769 [#:cache-dir "/var/cache/cat-avatar-generator"] @
19770 [#:package cat-avatar-generator] @
19771 [#:configuration (nginx-server-configuration)]
19772 Returns an nginx-server-configuration that inherits @code{configuration}. It
19773 extends the nginx configuration to add a server block that serves @code{package},
19774 a version of cat-avatar-generator. During execution, cat-avatar-generator will
19775 be able to use @code{cache-dir} as its cache directory.
19778 A simple setup for cat-avatar-generator can look like this:
19780 (services (cons* (cat-avatar-generator-service
19782 (nginx-server-configuration
19783 (server-name '("example.com"))))
19788 @subsubheading Hpcguix-web
19790 @cindex hpcguix-web
19791 The @uref{hpcguix-web, https://github.com/UMCUGenetics/hpcguix-web/}
19792 program is a customizable web interface to browse Guix packages,
19793 initially designed for users of high-performance computing (HPC)
19796 @defvr {Scheme Variable} hpcguix-web-service-type
19797 The service type for @code{hpcguix-web}.
19800 @deftp {Data Type} hpcguix-web-configuration
19801 Data type for the hpcguix-web service configuration.
19805 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
19806 configuration. The main items available in this spec are:
19809 @item @code{title-prefix} (default: @code{"hpcguix | "})
19810 The page title prefix.
19812 @item @code{guix-command} (default: @code{"guix"})
19813 The @command{guix} command.
19815 @item @code{package-filter-proc} (default: @code{(const #t)})
19816 A procedure specifying how to filter packages that are displayed.
19818 @item @code{package-page-extension-proc} (default: @code{(const '())})
19819 Extension package for @code{hpcguix-web}.
19821 @item @code{menu} (default: @code{'()})
19822 Additional entry in page @code{menu}.
19824 @item @code{channels} (default: @code{%default-channels})
19825 List of channels from which the package list is built (@pxref{Channels}).
19827 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
19828 The expiration time, in seconds, after which the package list is rebuilt from
19829 the latest instances of the given channels.
19832 See the hpcguix-web repository for a
19833 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
19836 @item @code{package} (default: @code{hpcguix-web})
19837 The hpcguix-web package to use.
19841 A typical hpcguix-web service declaration looks like this:
19844 (service hpcguix-web-service-type
19845 (hpcguix-web-configuration
19847 #~(define site-config
19848 (hpcweb-configuration
19849 (title-prefix "Guix-HPC - ")
19850 (menu '(("/about" "ABOUT"))))))))
19854 The hpcguix-web service periodically updates the package list it publishes by
19855 pulling channels from Git. To that end, it needs to access X.509 certificates
19856 so that it can authenticate Git servers when communicating over HTTPS, and it
19857 assumes that @file{/etc/ssl/certs} contains those certificates.
19859 Thus, make sure to add @code{nss-certs} or another certificate package to the
19860 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
19861 more information on X.509 certificates.
19864 @node Certificate Services
19865 @subsection Certificate Services
19868 @cindex HTTP, HTTPS
19869 @cindex Let's Encrypt
19870 @cindex TLS certificates
19871 The @code{(gnu services certbot)} module provides a service to
19872 automatically obtain a valid TLS certificate from the Let's Encrypt
19873 certificate authority. These certificates can then be used to serve
19874 content securely over HTTPS or other TLS-based protocols, with the
19875 knowledge that the client will be able to verify the server's
19878 @url{https://letsencrypt.org/, Let's Encrypt} provides the
19879 @code{certbot} tool to automate the certification process. This tool
19880 first securely generates a key on the server. It then makes a request
19881 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
19882 checks that the request originates from the host in question by using a
19883 challenge-response protocol, requiring the server to provide its
19884 response over HTTP. If that protocol completes successfully, the CA
19885 signs the key, resulting in a certificate. That certificate is valid
19886 for a limited period of time, and therefore to continue to provide TLS
19887 services, the server needs to periodically ask the CA to renew its
19890 The certbot service automates this process: the initial key
19891 generation, the initial certification request to the Let's Encrypt
19892 service, the web server challenge/response integration, writing the
19893 certificate to disk, the automated periodic renewals, and the deployment
19894 tasks associated with the renewal (e.g.@: reloading services, copying keys
19895 with different permissions).
19897 Certbot is run twice a day, at a random minute within the hour. It
19898 won't do anything until your certificates are due for renewal or
19899 revoked, but running it regularly would give your service a chance of
19900 staying online in case a Let's Encrypt-initiated revocation happened for
19903 By using this service, you agree to the ACME Subscriber Agreement, which
19904 can be found there:
19905 @url{https://acme-v01.api.letsencrypt.org/directory}.
19907 @defvr {Scheme Variable} certbot-service-type
19908 A service type for the @code{certbot} Let's Encrypt client. Its value
19909 must be a @code{certbot-configuration} record as in this example:
19912 (define %nginx-deploy-hook
19914 "nginx-deploy-hook"
19915 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
19916 (kill pid SIGHUP))))
19918 (service certbot-service-type
19919 (certbot-configuration
19920 (email "foo@@example.net")
19923 (certificate-configuration
19924 (domains '("example.net" "www.example.net"))
19925 (deploy-hook %nginx-deploy-hook))
19926 (certificate-configuration
19927 (domains '("bar.example.net")))))))
19930 See below for details about @code{certbot-configuration}.
19933 @deftp {Data Type} certbot-configuration
19934 Data type representing the configuration of the @code{certbot} service.
19935 This type has the following parameters:
19938 @item @code{package} (default: @code{certbot})
19939 The certbot package to use.
19941 @item @code{webroot} (default: @code{/var/www})
19942 The directory from which to serve the Let's Encrypt challenge/response
19945 @item @code{certificates} (default: @code{()})
19946 A list of @code{certificates-configuration}s for which to generate
19947 certificates and request signatures. Each certificate has a @code{name}
19948 and several @code{domains}.
19951 Mandatory email used for registration, recovery contact, and important
19952 account notifications.
19954 @item @code{rsa-key-size} (default: @code{2048})
19955 Size of the RSA key.
19957 @item @code{default-location} (default: @i{see below})
19958 The default @code{nginx-location-configuration}. Because @code{certbot}
19959 needs to be able to serve challenges and responses, it needs to be able
19960 to run a web server. It does so by extending the @code{nginx} web
19961 service with an @code{nginx-server-configuration} listening on the
19962 @var{domains} on port 80, and which has a
19963 @code{nginx-location-configuration} for the @code{/.well-known/} URI
19964 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
19965 these nginx configuration data types.
19967 Requests to other URL paths will be matched by the
19968 @code{default-location}, which if present is added to all
19969 @code{nginx-server-configuration}s.
19971 By default, the @code{default-location} will issue a redirect from
19972 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
19973 you to define what to serve on your site via @code{https}.
19975 Pass @code{#f} to not issue a default location.
19979 @deftp {Data Type} certificate-configuration
19980 Data type representing the configuration of a certificate.
19981 This type has the following parameters:
19984 @item @code{name} (default: @i{see below})
19985 This name is used by Certbot for housekeeping and in file paths; it
19986 doesn't affect the content of the certificate itself. To see
19987 certificate names, run @code{certbot certificates}.
19989 Its default is the first provided domain.
19991 @item @code{domains} (default: @code{()})
19992 The first domain provided will be the subject CN of the certificate, and
19993 all domains will be Subject Alternative Names on the certificate.
19995 @item @code{challenge} (default: @code{#f})
19996 The challenge type that has to be run by certbot. If @code{#f} is specified,
19997 default to the HTTP challenge. If a value is specified, defaults to the
19998 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
19999 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}).
20001 @item @code{authentication-hook} (default: @code{#f})
20002 Command to be run in a shell once for each certificate challenge to be
20003 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
20004 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
20005 contains the validation string and @code{$CERTBOT_TOKEN} contains the
20006 file name of the resource requested when performing an HTTP-01 challenge.
20008 @item @code{cleanup-hook} (default: @code{#f})
20009 Command to be run in a shell once for each certificate challenge that
20010 have been answered by the @code{auth-hook}. For this command, the shell
20011 variables available in the @code{auth-hook} script are still available, and
20012 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
20013 of the @code{auth-hook} script.
20015 @item @code{deploy-hook} (default: @code{#f})
20016 Command to be run in a shell once for each successfully issued
20017 certificate. For this command, the shell variable
20018 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
20019 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
20020 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
20021 contain a space-delimited list of renewed certificate domains (for
20022 example, @samp{"example.com www.example.com"}.
20027 For each @code{certificate-configuration}, the certificate is saved to
20028 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
20029 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
20031 @subsection DNS Services
20032 @cindex DNS (domain name system)
20033 @cindex domain name system (DNS)
20035 The @code{(gnu services dns)} module provides services related to the
20036 @dfn{domain name system} (DNS). It provides a server service for hosting
20037 an @emph{authoritative} DNS server for multiple zones, slave or master.
20038 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
20039 caching and forwarding DNS server for the LAN, which uses
20040 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
20042 @subsubheading Knot Service
20044 An example configuration of an authoritative server for two zones, one master
20048 (define-zone-entries example.org.zone
20049 ;; Name TTL Class Type Data
20050 ("@@" "" "IN" "A" "127.0.0.1")
20051 ("@@" "" "IN" "NS" "ns")
20052 ("ns" "" "IN" "A" "127.0.0.1"))
20054 (define master-zone
20055 (knot-zone-configuration
20056 (domain "example.org")
20058 (origin "example.org")
20059 (entries example.org.zone)))))
20062 (knot-zone-configuration
20063 (domain "plop.org")
20064 (dnssec-policy "default")
20065 (master (list "plop-master"))))
20067 (define plop-master
20068 (knot-remote-configuration
20070 (address (list "208.76.58.171"))))
20074 (services (cons* (service knot-service-type
20075 (knot-configuration
20076 (remotes (list plop-master))
20077 (zones (list master-zone slave-zone))))
20082 @deffn {Scheme Variable} knot-service-type
20083 This is the type for the Knot DNS server.
20085 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
20086 zones, that is to say domain names you would buy from a registrar. This server
20087 is not a resolver, meaning that it can only resolve names for which it is
20088 authoritative. This server can be configured to serve zones as a master server
20089 or a slave server as a per-zone basis. Slave zones will get their data from
20090 masters, and will serve it as an authoritative server. From the point of view
20091 of a resolver, there is no difference between master and slave.
20093 The following data types are used to configure the Knot DNS server:
20096 @deftp {Data Type} knot-key-configuration
20097 Data type representing a key.
20098 This type has the following parameters:
20101 @item @code{id} (default: @code{""})
20102 An identifier for other configuration fields to refer to this key. IDs must
20103 be unique and must not be empty.
20105 @item @code{algorithm} (default: @code{#f})
20106 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
20107 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
20108 and @code{'hmac-sha512}.
20110 @item @code{secret} (default: @code{""})
20111 The secret key itself.
20116 @deftp {Data Type} knot-acl-configuration
20117 Data type representing an Access Control List (ACL) configuration.
20118 This type has the following parameters:
20121 @item @code{id} (default: @code{""})
20122 An identifier for ether configuration fields to refer to this key. IDs must be
20123 unique and must not be empty.
20125 @item @code{address} (default: @code{'()})
20126 An ordered list of IP addresses, network subnets, or network ranges represented
20127 with strings. The query must match one of them. Empty value means that
20128 address match is not required.
20130 @item @code{key} (default: @code{'()})
20131 An ordered list of references to keys represented with strings. The string
20132 must match a key ID defined in a @code{knot-key-configuration}. No key means
20133 that a key is not require to match that ACL.
20135 @item @code{action} (default: @code{'()})
20136 An ordered list of actions that are permitted or forbidden by this ACL. Possible
20137 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
20138 and @code{'update}.
20140 @item @code{deny?} (default: @code{#f})
20141 When true, the ACL defines restrictions. Listed actions are forbidden. When
20142 false, listed actions are allowed.
20147 @deftp {Data Type} zone-entry
20148 Data type represnting a record entry in a zone file.
20149 This type has the following parameters:
20152 @item @code{name} (default: @code{"@@"})
20153 The name of the record. @code{"@@"} refers to the origin of the zone. Names
20154 are relative to the origin of the zone. For example, in the @code{example.org}
20155 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
20156 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
20157 refers to @code{ns.example.org}.
20159 @item @code{ttl} (default: @code{""})
20160 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
20162 @item @code{class} (default: @code{"IN"})
20163 The class of the record. Knot currently supports only @code{"IN"} and
20164 partially @code{"CH"}.
20166 @item @code{type} (default: @code{"A"})
20167 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
20168 address), NS (Name Server) and MX (Mail eXchange). Many other types are
20171 @item @code{data} (default: @code{""})
20172 The data contained in the record. For instance an IP address associated with
20173 an A record, or a domain name associated with an NS record. Remember that
20174 domain names are relative to the origin unless they end with a dot.
20179 @deftp {Data Type} zone-file
20180 Data type representing the content of a zone file.
20181 This type has the following parameters:
20184 @item @code{entries} (default: @code{'()})
20185 The list of entries. The SOA record is taken care of, so you don't need to
20186 put it in the list of entries. This list should probably contain an entry
20187 for your primary authoritative DNS server. Other than using a list of entries
20188 directly, you can use @code{define-zone-entries} to define a object containing
20189 the list of entries more easily, that you can later pass to the @code{entries}
20190 field of the @code{zone-file}.
20192 @item @code{origin} (default: @code{""})
20193 The name of your zone. This parameter cannot be empty.
20195 @item @code{ns} (default: @code{"ns"})
20196 The domain of your primary authoritative DNS server. The name is relative to
20197 the origin, unless it ends with a dot. It is mandatory that this primary
20198 DNS server corresponds to an NS record in the zone and that it is associated
20199 to an IP address in the list of entries.
20201 @item @code{mail} (default: @code{"hostmaster"})
20202 An email address people can contact you at, as the owner of the zone. This
20203 is translated as @code{<mail>@@<origin>}.
20205 @item @code{serial} (default: @code{1})
20206 The serial number of the zone. As this is used to keep track of changes by
20207 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
20208 Always increment it when you make a change in your zone.
20210 @item @code{refresh} (default: @code{(* 2 24 3600)})
20211 The frequency at which slaves will do a zone transfer. This value is a number
20212 of seconds. It can be computed by multiplications or with
20213 @code{(string->duration)}.
20215 @item @code{retry} (default: @code{(* 15 60)})
20216 The period after which a slave will retry to contact its master when it fails
20217 to do so a first time.
20219 @item @code{expiry} (default: @code{(* 14 24 3600)})
20220 Default TTL of records. Existing records are considered correct for at most
20221 this amount of time. After this period, resolvers will invalidate their cache
20222 and check again that it still exists.
20224 @item @code{nx} (default: @code{3600})
20225 Default TTL of inexistant records. This delay is usually short because you want
20226 your new domains to reach everyone quickly.
20231 @deftp {Data Type} knot-remote-configuration
20232 Data type representing a remote configuration.
20233 This type has the following parameters:
20236 @item @code{id} (default: @code{""})
20237 An identifier for other configuration fields to refer to this remote. IDs must
20238 be unique and must not be empty.
20240 @item @code{address} (default: @code{'()})
20241 An ordered list of destination IP addresses. Addresses are tried in sequence.
20242 An optional port can be given with the @@ separator. For instance:
20243 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
20245 @item @code{via} (default: @code{'()})
20246 An ordered list of source IP addresses. An empty list will have Knot choose
20247 an appropriate source IP. An optional port can be given with the @@ separator.
20248 The default is to choose at random.
20250 @item @code{key} (default: @code{#f})
20251 A reference to a key, that is a string containing the identifier of a key
20252 defined in a @code{knot-key-configuration} field.
20257 @deftp {Data Type} knot-keystore-configuration
20258 Data type representing a keystore to hold dnssec keys.
20259 This type has the following parameters:
20262 @item @code{id} (default: @code{""})
20263 The id of the keystore. It must not be empty.
20265 @item @code{backend} (default: @code{'pem})
20266 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
20268 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
20269 The configuration string of the backend. An example for the PKCS#11 is:
20270 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
20271 For the pem backend, the string reprensents a path in the file system.
20276 @deftp {Data Type} knot-policy-configuration
20277 Data type representing a dnssec policy. Knot DNS is able to automatically
20278 sign your zones. It can either generate and manage your keys automatically or
20279 use keys that you generate.
20281 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
20282 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
20283 zone. In order to be trusted, the KSK needs to be present in the parent zone
20284 (usually a top-level domain). If your registrar supports dnssec, you will
20285 have to send them your KSK's hash so they can add a DS record in their zone.
20286 This is not automated and need to be done each time you change your KSK.
20288 The policy also defines the lifetime of keys. Usually, ZSK can be changed
20289 easily and use weaker cryptographic functions (they use lower parameters) in
20290 order to sign records quickly, so they are changed often. The KSK however
20291 requires manual interaction with the registrar, so they are changed less often
20292 and use stronger parameters because they sign only one record.
20294 This type has the following parameters:
20297 @item @code{id} (default: @code{""})
20298 The id of the policy. It must not be empty.
20300 @item @code{keystore} (default: @code{"default"})
20301 A reference to a keystore, that is a string containing the identifier of a
20302 keystore defined in a @code{knot-keystore-configuration} field. The
20303 @code{"default"} identifier means the default keystore (a kasp database that
20304 was setup by this service).
20306 @item @code{manual?} (default: @code{#f})
20307 Whether the key management is manual or automatic.
20309 @item @code{single-type-signing?} (default: @code{#f})
20310 When @code{#t}, use the Single-Type Signing Scheme.
20312 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
20313 An algorithm of signing keys and issued signatures.
20315 @item @code{ksk-size} (default: @code{256})
20316 The length of the KSK. Note that this value is correct for the default
20317 algorithm, but would be unsecure for other algorithms.
20319 @item @code{zsk-size} (default: @code{256})
20320 The length of the ZSK. Note that this value is correct for the default
20321 algorithm, but would be unsecure for other algorithms.
20323 @item @code{dnskey-ttl} (default: @code{'default})
20324 The TTL value for DNSKEY records added into zone apex. The special
20325 @code{'default} value means same as the zone SOA TTL.
20327 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
20328 The period between ZSK publication and the next rollover initiation.
20330 @item @code{propagation-delay} (default: @code{(* 24 3600)})
20331 An extra delay added for each key rollover step. This value should be high
20332 enough to cover propagation of data from the master server to all slaves.
20334 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
20335 A validity period of newly issued signatures.
20337 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
20338 A period how long before a signature expiration the signature will be refreshed.
20340 @item @code{nsec3?} (default: @code{#f})
20341 When @code{#t}, NSEC3 will be used instead of NSEC.
20343 @item @code{nsec3-iterations} (default: @code{5})
20344 The number of additional times the hashing is performed.
20346 @item @code{nsec3-salt-length} (default: @code{8})
20347 The length of a salt field in octets, which is appended to the original owner
20348 name before hashing.
20350 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
20351 The validity period of newly issued salt field.
20356 @deftp {Data Type} knot-zone-configuration
20357 Data type representing a zone served by Knot.
20358 This type has the following parameters:
20361 @item @code{domain} (default: @code{""})
20362 The domain served by this configuration. It must not be empty.
20364 @item @code{file} (default: @code{""})
20365 The file where this zone is saved. This parameter is ignored by master zones.
20366 Empty means default location that depends on the domain name.
20368 @item @code{zone} (default: @code{(zone-file)})
20369 The content of the zone file. This parameter is ignored by slave zones. It
20370 must contain a zone-file record.
20372 @item @code{master} (default: @code{'()})
20373 A list of master remotes. When empty, this zone is a master. When set, this
20374 zone is a slave. This is a list of remotes identifiers.
20376 @item @code{ddns-master} (default: @code{#f})
20377 The main master. When empty, it defaults to the first master in the list of
20380 @item @code{notify} (default: @code{'()})
20381 A list of slave remote identifiers.
20383 @item @code{acl} (default: @code{'()})
20384 A list of acl identifiers.
20386 @item @code{semantic-checks?} (default: @code{#f})
20387 When set, this adds more semantic checks to the zone.
20389 @item @code{disable-any?} (default: @code{#f})
20390 When set, this forbids queries of the ANY type.
20392 @item @code{zonefile-sync} (default: @code{0})
20393 The delay between a modification in memory and on disk. 0 means immediate
20396 @item @code{zonefile-load} (default: @code{#f})
20397 The way the zone file contents are applied during zone load. Possible values
20401 @item @code{#f} for using the default value from Knot,
20402 @item @code{'none} for not using the zone file at all,
20403 @item @code{'difference} for computing the difference between already available
20404 contents and zone contents and applying it to the current zone contents,
20405 @item @code{'difference-no-serial} for the same as @code{'difference}, but
20406 ignoring the SOA serial in the zone file, while the server takes care of it
20408 @item @code{'whole} for loading zone contents from the zone file.
20411 @item @code{journal-content} (default: @code{#f})
20412 The way the journal is used to store zone and its changes. Possible values
20413 are @code{'none} to not use it at all, @code{'changes} to store changes and
20414 @code{'all} to store contents. @code{#f} does not set this option, so the
20415 default value from Knot is used.
20417 @item @code{max-journal-usage} (default: @code{#f})
20418 The maximum size for the journal on disk. @code{#f} does not set this option,
20419 so the default value from Knot is used.
20421 @item @code{max-journal-depth} (default: @code{#f})
20422 The maximum size of the history. @code{#f} does not set this option, so the
20423 default value from Knot is used.
20425 @item @code{max-zone-size} (default: @code{#f})
20426 The maximum size of the zone file. This limit is enforced for incoming
20427 transfer and updates. @code{#f} does not set this option, so the default
20428 value from Knot is used.
20430 @item @code{dnssec-policy} (default: @code{#f})
20431 A reference to a @code{knot-policy-configuration} record, or the special
20432 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
20435 @item @code{serial-policy} (default: @code{'increment})
20436 A policy between @code{'increment} and @code{'unixtime}.
20441 @deftp {Data Type} knot-configuration
20442 Data type representing the Knot configuration.
20443 This type has the following parameters:
20446 @item @code{knot} (default: @code{knot})
20449 @item @code{run-directory} (default: @code{"/var/run/knot"})
20450 The run directory. This directory will be used for pid file and sockets.
20452 @item @code{includes} (default: @code{'()})
20453 A list of strings or file-like objects denoting other files that must be
20454 included at the top of the configuration file.
20456 @cindex secrets, Knot service
20457 This can be used to manage secrets out-of-band. For example, secret
20458 keys may be stored in an out-of-band file not managed by Guix, and
20459 thus not visible in @file{/gnu/store}---e.g., you could store secret
20460 key configuration in @file{/etc/knot/secrets.conf} and add this file
20461 to the @code{includes} list.
20463 It can also be used to add configuration not supported by this interface.
20465 @item @code{listen-v4} (default: @code{"0.0.0.0"})
20466 An ip address on which to listen.
20468 @item @code{listen-v6} (default: @code{"::"})
20469 An ip address on which to listen.
20471 @item @code{listen-port} (default: @code{53})
20472 A port on which to listen.
20474 @item @code{keys} (default: @code{'()})
20475 The list of knot-key-configuration used by this configuration.
20477 @item @code{acls} (default: @code{'()})
20478 The list of knot-acl-configuration used by this configuration.
20480 @item @code{remotes} (default: @code{'()})
20481 The list of knot-remote-configuration used by this configuration.
20483 @item @code{zones} (default: @code{'()})
20484 The list of knot-zone-configuration used by this configuration.
20489 @subsubheading Dnsmasq Service
20491 @deffn {Scheme Variable} dnsmasq-service-type
20492 This is the type of the dnsmasq service, whose value should be an
20493 @code{dnsmasq-configuration} object as in this example:
20496 (service dnsmasq-service-type
20497 (dnsmasq-configuration
20499 (servers '("192.168.1.1"))))
20503 @deftp {Data Type} dnsmasq-configuration
20504 Data type representing the configuration of dnsmasq.
20507 @item @code{package} (default: @var{dnsmasq})
20508 Package object of the dnsmasq server.
20510 @item @code{no-hosts?} (default: @code{#f})
20511 When true, don't read the hostnames in /etc/hosts.
20513 @item @code{port} (default: @code{53})
20514 The port to listen on. Setting this to zero completely disables DNS
20515 responses, leaving only DHCP and/or TFTP functions.
20517 @item @code{local-service?} (default: @code{#t})
20518 Accept DNS queries only from hosts whose address is on a local subnet,
20519 ie a subnet for which an interface exists on the server.
20521 @item @code{listen-addresses} (default: @code{'()})
20522 Listen on the given IP addresses.
20524 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
20525 The file to read the IP address of the upstream nameservers from.
20527 @item @code{no-resolv?} (default: @code{#f})
20528 When true, don't read @var{resolv-file}.
20530 @item @code{servers} (default: @code{'()})
20531 Specify IP address of upstream servers directly.
20533 @item @code{cache-size} (default: @code{150})
20534 Set the size of dnsmasq's cache. Setting the cache size to zero
20537 @item @code{negative-cache?} (default: @code{#t})
20538 When false, disable negative caching.
20543 @subsubheading ddclient Service
20546 The ddclient service described below runs the ddclient daemon, which takes
20547 care of automatically updating DNS entries for service providers such as
20548 @uref{https://dyn.com/dns/, Dyn}.
20550 The following example show instantiates the service with its default
20554 (service ddclient-service-type)
20557 Note that ddclient needs to access credentials that are stored in a
20558 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
20559 @code{secret-file} below.) You are expected to create this file manually, in
20560 an ``out-of-band'' fashion (you @emph{could} make this file part of the
20561 service configuration, for instance by using @code{plain-file}, but it will be
20562 world-readable @i{via} @file{/gnu/store}.) See the examples in the
20563 @file{share/ddclient} directory of the @code{ddclient} package.
20565 @c %start of fragment
20567 Available @code{ddclient-configuration} fields are:
20569 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
20570 The ddclient package.
20574 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
20575 The period after which ddclient will retry to check IP and domain name.
20577 Defaults to @samp{300}.
20581 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
20582 Use syslog for the output.
20584 Defaults to @samp{#t}.
20588 @deftypevr {@code{ddclient-configuration} parameter} string mail
20591 Defaults to @samp{"root"}.
20595 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
20596 Mail failed update to user.
20598 Defaults to @samp{"root"}.
20602 @deftypevr {@code{ddclient-configuration} parameter} string pid
20603 The ddclient PID file.
20605 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
20609 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
20610 Enable SSL support.
20612 Defaults to @samp{#t}.
20616 @deftypevr {@code{ddclient-configuration} parameter} string user
20617 Specifies the user name or ID that is used when running ddclient
20620 Defaults to @samp{"ddclient"}.
20624 @deftypevr {@code{ddclient-configuration} parameter} string group
20625 Group of the user who will run the ddclient program.
20627 Defaults to @samp{"ddclient"}.
20631 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
20632 Secret file which will be appended to @file{ddclient.conf} file. This
20633 file contains credentials for use by ddclient. You are expected to
20634 create it manually.
20636 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
20640 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
20641 Extra options will be appended to @file{ddclient.conf} file.
20643 Defaults to @samp{()}.
20648 @c %end of fragment
20652 @subsection VPN Services
20653 @cindex VPN (virtual private network)
20654 @cindex virtual private network (VPN)
20656 The @code{(gnu services vpn)} module provides services related to
20657 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
20658 your machine to connect to a VPN, and a @emph{server} service for your machine
20659 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
20661 @deffn {Scheme Procedure} openvpn-client-service @
20662 [#:config (openvpn-client-configuration)]
20664 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
20667 @deffn {Scheme Procedure} openvpn-server-service @
20668 [#:config (openvpn-server-configuration)]
20670 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
20672 Both can be run simultaneously.
20675 @c %automatically generated documentation
20677 Available @code{openvpn-client-configuration} fields are:
20679 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
20680 The OpenVPN package.
20684 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
20685 The OpenVPN pid file.
20687 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
20691 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
20692 The protocol (UDP or TCP) used to open a channel between clients and
20695 Defaults to @samp{udp}.
20699 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
20700 The device type used to represent the VPN connection.
20702 Defaults to @samp{tun}.
20706 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
20707 The certificate authority to check connections against.
20709 Defaults to @samp{"/etc/openvpn/ca.crt"}.
20713 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
20714 The certificate of the machine the daemon is running on. It should be
20715 signed by the authority given in @code{ca}.
20717 Defaults to @samp{"/etc/openvpn/client.crt"}.
20721 @deftypevr {@code{openvpn-client-configuration} parameter} string key
20722 The key of the machine the daemon is running on. It must be the key whose
20723 certificate is @code{cert}.
20725 Defaults to @samp{"/etc/openvpn/client.key"}.
20729 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
20730 Whether to use the lzo compression algorithm.
20732 Defaults to @samp{#t}.
20736 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
20737 Don't re-read key files across SIGUSR1 or --ping-restart.
20739 Defaults to @samp{#t}.
20743 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
20744 Don't close and reopen TUN/TAP device or run up/down scripts across
20745 SIGUSR1 or --ping-restart restarts.
20747 Defaults to @samp{#t}.
20751 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
20754 Defaults to @samp{3}.
20758 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
20759 Add an additional layer of HMAC authentication on top of the TLS control
20760 channel to protect against DoS attacks.
20762 Defaults to @samp{#f}.
20766 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
20767 Whether to check the server certificate has server usage extension.
20769 Defaults to @samp{#t}.
20773 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
20774 Bind to a specific local port number.
20776 Defaults to @samp{#f}.
20780 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
20781 Retry resolving server address.
20783 Defaults to @samp{#t}.
20787 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
20788 A list of remote servers to connect to.
20790 Defaults to @samp{()}.
20792 Available @code{openvpn-remote-configuration} fields are:
20794 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
20797 Defaults to @samp{"my-server"}.
20801 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
20802 Port number the server listens to.
20804 Defaults to @samp{1194}.
20809 @c %end of automatic openvpn-client documentation
20811 @c %automatically generated documentation
20813 Available @code{openvpn-server-configuration} fields are:
20815 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
20816 The OpenVPN package.
20820 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
20821 The OpenVPN pid file.
20823 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
20827 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
20828 The protocol (UDP or TCP) used to open a channel between clients and
20831 Defaults to @samp{udp}.
20835 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
20836 The device type used to represent the VPN connection.
20838 Defaults to @samp{tun}.
20842 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
20843 The certificate authority to check connections against.
20845 Defaults to @samp{"/etc/openvpn/ca.crt"}.
20849 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
20850 The certificate of the machine the daemon is running on. It should be
20851 signed by the authority given in @code{ca}.
20853 Defaults to @samp{"/etc/openvpn/client.crt"}.
20857 @deftypevr {@code{openvpn-server-configuration} parameter} string key
20858 The key of the machine the daemon is running on. It must be the key whose
20859 certificate is @code{cert}.
20861 Defaults to @samp{"/etc/openvpn/client.key"}.
20865 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
20866 Whether to use the lzo compression algorithm.
20868 Defaults to @samp{#t}.
20872 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
20873 Don't re-read key files across SIGUSR1 or --ping-restart.
20875 Defaults to @samp{#t}.
20879 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
20880 Don't close and reopen TUN/TAP device or run up/down scripts across
20881 SIGUSR1 or --ping-restart restarts.
20883 Defaults to @samp{#t}.
20887 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
20890 Defaults to @samp{3}.
20894 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
20895 Add an additional layer of HMAC authentication on top of the TLS control
20896 channel to protect against DoS attacks.
20898 Defaults to @samp{#f}.
20902 @deftypevr {@code{openvpn-server-configuration} parameter} number port
20903 Specifies the port number on which the server listens.
20905 Defaults to @samp{1194}.
20909 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
20910 An ip and mask specifying the subnet inside the virtual network.
20912 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
20916 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
20917 A CIDR notation specifying the IPv6 subnet inside the virtual network.
20919 Defaults to @samp{#f}.
20923 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
20924 The Diffie-Hellman parameters file.
20926 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
20930 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
20931 The file that records client IPs.
20933 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
20937 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
20938 When true, the server will act as a gateway for its clients.
20940 Defaults to @samp{#f}.
20944 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
20945 When true, clients are allowed to talk to each other inside the VPN.
20947 Defaults to @samp{#f}.
20951 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
20952 Causes ping-like messages to be sent back and forth over the link so
20953 that each side knows when the other side has gone down. @code{keepalive}
20954 requires a pair. The first element is the period of the ping sending,
20955 and the second element is the timeout before considering the other side
20960 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
20961 The maximum number of clients.
20963 Defaults to @samp{100}.
20967 @deftypevr {@code{openvpn-server-configuration} parameter} string status
20968 The status file. This file shows a small report on current connection.
20969 It is truncated and rewritten every minute.
20971 Defaults to @samp{"/var/run/openvpn/status"}.
20975 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
20976 The list of configuration for some clients.
20978 Defaults to @samp{()}.
20980 Available @code{openvpn-ccd-configuration} fields are:
20982 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
20985 Defaults to @samp{"client"}.
20989 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
20992 Defaults to @samp{#f}.
20996 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
20999 Defaults to @samp{#f}.
21006 @c %end of automatic openvpn-server documentation
21009 @node Network File System
21010 @subsection Network File System
21013 The @code{(gnu services nfs)} module provides the following services,
21014 which are most commonly used in relation to mounting or exporting
21015 directory trees as @dfn{network file systems} (NFS).
21017 @subsubheading RPC Bind Service
21020 The RPC Bind service provides a facility to map program numbers into
21021 universal addresses.
21022 Many NFS related services use this facility. Hence it is automatically
21023 started when a dependent service starts.
21025 @defvr {Scheme Variable} rpcbind-service-type
21026 A service type for the RPC portmapper daemon.
21030 @deftp {Data Type} rpcbind-configuration
21031 Data type representing the configuration of the RPC Bind Service.
21032 This type has the following parameters:
21034 @item @code{rpcbind} (default: @code{rpcbind})
21035 The rpcbind package to use.
21037 @item @code{warm-start?} (default: @code{#t})
21038 If this parameter is @code{#t}, then the daemon will read a
21039 state file on startup thus reloading state information saved by a previous
21045 @subsubheading Pipefs Pseudo File System
21049 The pipefs file system is used to transfer NFS related data
21050 between the kernel and user space programs.
21052 @defvr {Scheme Variable} pipefs-service-type
21053 A service type for the pipefs pseudo file system.
21056 @deftp {Data Type} pipefs-configuration
21057 Data type representing the configuration of the pipefs pseudo file system service.
21058 This type has the following parameters:
21060 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21061 The directory to which the file system is to be attached.
21066 @subsubheading GSS Daemon Service
21069 @cindex global security system
21071 The @dfn{global security system} (GSS) daemon provides strong security for RPC
21073 Before exchanging RPC requests an RPC client must establish a security
21074 context. Typically this is done using the Kerberos command @command{kinit}
21075 or automatically at login time using PAM services (@pxref{Kerberos Services}).
21077 @defvr {Scheme Variable} gss-service-type
21078 A service type for the Global Security System (GSS) daemon.
21081 @deftp {Data Type} gss-configuration
21082 Data type representing the configuration of the GSS daemon service.
21083 This type has the following parameters:
21085 @item @code{nfs-utils} (default: @code{nfs-utils})
21086 The package in which the @command{rpc.gssd} command is to be found.
21088 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21089 The directory where the pipefs file system is mounted.
21095 @subsubheading IDMAP Daemon Service
21097 @cindex name mapper
21099 The idmap daemon service provides mapping between user IDs and user names.
21100 Typically it is required in order to access file systems mounted via NFSv4.
21102 @defvr {Scheme Variable} idmap-service-type
21103 A service type for the Identity Mapper (IDMAP) daemon.
21106 @deftp {Data Type} idmap-configuration
21107 Data type representing the configuration of the IDMAP daemon service.
21108 This type has the following parameters:
21110 @item @code{nfs-utils} (default: @code{nfs-utils})
21111 The package in which the @command{rpc.idmapd} command is to be found.
21113 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21114 The directory where the pipefs file system is mounted.
21116 @item @code{domain} (default: @code{#f})
21117 The local NFSv4 domain name.
21118 This must be a string or @code{#f}.
21119 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
21124 @node Continuous Integration
21125 @subsection Continuous Integration
21127 @cindex continuous integration
21128 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
21129 continuous integration tool for Guix. It can be used both for development and
21130 for providing substitutes to others (@pxref{Substitutes}).
21132 The @code{(gnu services cuirass)} module provides the following service.
21134 @defvr {Scheme Procedure} cuirass-service-type
21135 The type of the Cuirass service. Its value must be a
21136 @code{cuirass-configuration} object, as described below.
21139 To add build jobs, you have to set the @code{specifications} field of the
21140 configuration. Here is an example of a service that polls the Guix repository
21141 and builds the packages from a manifest. Some of the packages are defined in
21142 the @code{"custom-packages"} input, which is the equivalent of
21143 @code{GUIX_PACKAGE_PATH}.
21146 (define %cuirass-specs
21148 '((#:name . "my-manifest")
21149 (#:load-path-inputs . ("guix"))
21150 (#:package-path-inputs . ("custom-packages"))
21151 (#:proc-input . "guix")
21152 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
21153 (#:proc . cuirass-jobs)
21154 (#:proc-args . ((subset . "manifests")
21155 (systems . ("x86_64-linux"))
21156 (manifests . (("config" . "guix/manifest.scm")))))
21157 (#:inputs . (((#:name . "guix")
21158 (#:url . "git://git.savannah.gnu.org/guix.git")
21159 (#:load-path . ".")
21160 (#:branch . "master")
21161 (#:no-compile? . #t))
21162 ((#:name . "config")
21163 (#:url . "git://git.example.org/config.git")
21164 (#:load-path . ".")
21165 (#:branch . "master")
21166 (#:no-compile? . #t))
21167 ((#:name . "custom-packages")
21168 (#:url . "git://git.example.org/custom-packages.git")
21169 (#:load-path . ".")
21170 (#:branch . "master")
21171 (#:no-compile? . #t)))))))
21173 (service cuirass-service-type
21174 (cuirass-configuration
21175 (specifications %cuirass-specs)))
21178 While information related to build jobs is located directly in the
21179 specifications, global settings for the @command{cuirass} process are
21180 accessible in other @code{cuirass-configuration} fields.
21182 @deftp {Data Type} cuirass-configuration
21183 Data type representing the configuration of Cuirass.
21186 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
21187 Location of the log file.
21189 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
21190 Location of the repository cache.
21192 @item @code{user} (default: @code{"cuirass"})
21193 Owner of the @code{cuirass} process.
21195 @item @code{group} (default: @code{"cuirass"})
21196 Owner's group of the @code{cuirass} process.
21198 @item @code{interval} (default: @code{60})
21199 Number of seconds between the poll of the repositories followed by the
21202 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
21203 Location of sqlite database which contains the build results and previously
21204 added specifications.
21206 @item @code{ttl} (default: @code{(* 30 24 3600)})
21207 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
21208 are registered for build results. This means that build results are protected
21209 from garbage collection for at least @var{ttl} seconds.
21211 @item @code{port} (default: @code{8081})
21212 Port number used by the HTTP server.
21214 @item --listen=@var{host}
21215 Listen on the network interface for @var{host}. The default is to
21216 accept connections from localhost.
21218 @item @code{specifications} (default: @code{#~'()})
21219 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
21220 where a specification is an association list
21221 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
21222 keys are keywords (@code{#:keyword-example}) as shown in the example
21225 @item @code{use-substitutes?} (default: @code{#f})
21226 This allows using substitutes to avoid building every dependencies of a job
21229 @item @code{one-shot?} (default: @code{#f})
21230 Only evaluate specifications and build derivations once.
21232 @item @code{fallback?} (default: @code{#f})
21233 When substituting a pre-built binary fails, fall back to building
21236 @item @code{cuirass} (default: @code{cuirass})
21237 The Cuirass package to use.
21241 @node Power Management Services
21242 @subsection Power Management Services
21245 @cindex power management with TLP
21246 @subsubheading TLP daemon
21248 The @code{(gnu services pm)} module provides a Guix service definition
21249 for the Linux power management tool TLP.
21251 TLP enables various powersaving modes in userspace and kernel.
21252 Contrary to @code{upower-service}, it is not a passive,
21253 monitoring tool, as it will apply custom settings each time a new power
21254 source is detected. More information can be found at
21255 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
21257 @deffn {Scheme Variable} tlp-service-type
21258 The service type for the TLP tool. Its value should be a valid
21259 TLP configuration (see below). To use the default settings, simply
21262 (service tlp-service-type)
21266 By default TLP does not need much configuration but most TLP parameters
21267 can be tweaked using @code{tlp-configuration}.
21269 Each parameter definition is preceded by its type; for example,
21270 @samp{boolean foo} indicates that the @code{foo} parameter
21271 should be specified as a boolean. Types starting with
21272 @code{maybe-} denote parameters that won't show up in TLP config file
21273 when their value is @code{'disabled}.
21275 @c The following documentation was initially generated by
21276 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
21277 @c documentation is better, so we shouldn't hesitate to edit below as
21278 @c needed. However if the change you want to make to this documentation
21279 @c can be done in an automated way, it's probably easier to change
21280 @c (generate-documentation) than to make it below and have to deal with
21281 @c the churn as TLP updates.
21283 Available @code{tlp-configuration} fields are:
21285 @deftypevr {@code{tlp-configuration} parameter} package tlp
21290 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
21291 Set to true if you wish to enable TLP.
21293 Defaults to @samp{#t}.
21297 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
21298 Default mode when no power supply can be detected. Alternatives are AC
21301 Defaults to @samp{"AC"}.
21305 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
21306 Number of seconds Linux kernel has to wait after the disk goes idle,
21307 before syncing on AC.
21309 Defaults to @samp{0}.
21313 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
21314 Same as @code{disk-idle-ac} but on BAT mode.
21316 Defaults to @samp{2}.
21320 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
21321 Dirty pages flushing periodicity, expressed in seconds.
21323 Defaults to @samp{15}.
21327 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
21328 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
21330 Defaults to @samp{60}.
21334 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
21335 CPU frequency scaling governor on AC mode. With intel_pstate driver,
21336 alternatives are powersave and performance. With acpi-cpufreq driver,
21337 alternatives are ondemand, powersave, performance and conservative.
21339 Defaults to @samp{disabled}.
21343 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
21344 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
21346 Defaults to @samp{disabled}.
21350 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
21351 Set the min available frequency for the scaling governor on AC.
21353 Defaults to @samp{disabled}.
21357 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
21358 Set the max available frequency for the scaling governor on AC.
21360 Defaults to @samp{disabled}.
21364 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
21365 Set the min available frequency for the scaling governor on BAT.
21367 Defaults to @samp{disabled}.
21371 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
21372 Set the max available frequency for the scaling governor on BAT.
21374 Defaults to @samp{disabled}.
21378 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
21379 Limit the min P-state to control the power dissipation of the CPU, in AC
21380 mode. Values are stated as a percentage of the available performance.
21382 Defaults to @samp{disabled}.
21386 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
21387 Limit the max P-state to control the power dissipation of the CPU, in AC
21388 mode. Values are stated as a percentage of the available performance.
21390 Defaults to @samp{disabled}.
21394 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
21395 Same as @code{cpu-min-perf-on-ac} on BAT mode.
21397 Defaults to @samp{disabled}.
21401 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
21402 Same as @code{cpu-max-perf-on-ac} on BAT mode.
21404 Defaults to @samp{disabled}.
21408 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
21409 Enable CPU turbo boost feature on AC mode.
21411 Defaults to @samp{disabled}.
21415 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
21416 Same as @code{cpu-boost-on-ac?} on BAT mode.
21418 Defaults to @samp{disabled}.
21422 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
21423 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
21424 used under light load conditions.
21426 Defaults to @samp{#f}.
21430 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
21431 Same as @code{sched-powersave-on-ac?} but on BAT mode.
21433 Defaults to @samp{#t}.
21437 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
21438 Enable Linux kernel NMI watchdog.
21440 Defaults to @samp{#f}.
21444 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
21445 For Linux kernels with PHC patch applied, change CPU voltages. An
21446 example value would be @samp{"F:V F:V F:V F:V"}.
21448 Defaults to @samp{disabled}.
21452 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
21453 Set CPU performance versus energy saving policy on AC. Alternatives are
21454 performance, normal, powersave.
21456 Defaults to @samp{"performance"}.
21460 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
21461 Same as @code{energy-perf-policy-ac} but on BAT mode.
21463 Defaults to @samp{"powersave"}.
21467 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
21472 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
21473 Hard disk advanced power management level.
21477 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
21478 Same as @code{disk-apm-bat} but on BAT mode.
21482 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
21483 Hard disk spin down timeout. One value has to be specified for each
21484 declared hard disk.
21486 Defaults to @samp{disabled}.
21490 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
21491 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
21493 Defaults to @samp{disabled}.
21497 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
21498 Select IO scheduler for disk devices. One value has to be specified for
21499 each declared hard disk. Example alternatives are cfq, deadline and
21502 Defaults to @samp{disabled}.
21506 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
21507 SATA aggressive link power management (ALPM) level. Alternatives are
21508 min_power, medium_power, max_performance.
21510 Defaults to @samp{"max_performance"}.
21514 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
21515 Same as @code{sata-linkpwr-ac} but on BAT mode.
21517 Defaults to @samp{"min_power"}.
21521 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
21522 Exclude specified SATA host devices for link power management.
21524 Defaults to @samp{disabled}.
21528 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
21529 Enable Runtime Power Management for AHCI controller and disks on AC
21532 Defaults to @samp{disabled}.
21536 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
21537 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
21539 Defaults to @samp{disabled}.
21543 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
21544 Seconds of inactivity before disk is suspended.
21546 Defaults to @samp{15}.
21550 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
21551 PCI Express Active State Power Management level. Alternatives are
21552 default, performance, powersave.
21554 Defaults to @samp{"performance"}.
21558 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
21559 Same as @code{pcie-aspm-ac} but on BAT mode.
21561 Defaults to @samp{"powersave"}.
21565 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
21566 Radeon graphics clock speed level. Alternatives are low, mid, high,
21569 Defaults to @samp{"high"}.
21573 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
21574 Same as @code{radeon-power-ac} but on BAT mode.
21576 Defaults to @samp{"low"}.
21580 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
21581 Radeon dynamic power management method (DPM). Alternatives are battery,
21584 Defaults to @samp{"performance"}.
21588 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
21589 Same as @code{radeon-dpm-state-ac} but on BAT mode.
21591 Defaults to @samp{"battery"}.
21595 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
21596 Radeon DPM performance level. Alternatives are auto, low, high.
21598 Defaults to @samp{"auto"}.
21602 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
21603 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
21605 Defaults to @samp{"auto"}.
21609 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
21610 Wifi power saving mode.
21612 Defaults to @samp{#f}.
21616 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
21617 Same as @code{wifi-power-ac?} but on BAT mode.
21619 Defaults to @samp{#t}.
21623 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
21624 Disable wake on LAN.
21626 Defaults to @samp{#t}.
21630 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
21631 Timeout duration in seconds before activating audio power saving on
21632 Intel HDA and AC97 devices. A value of 0 disables power saving.
21634 Defaults to @samp{0}.
21638 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
21639 Same as @code{sound-powersave-ac} but on BAT mode.
21641 Defaults to @samp{1}.
21645 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
21646 Disable controller in powersaving mode on Intel HDA devices.
21648 Defaults to @samp{#t}.
21652 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
21653 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
21654 powered on again by releasing (and reinserting) the eject lever or by
21655 pressing the disc eject button on newer models.
21657 Defaults to @samp{#f}.
21661 @deftypevr {@code{tlp-configuration} parameter} string bay-device
21662 Name of the optical drive device to power off.
21664 Defaults to @samp{"sr0"}.
21668 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
21669 Runtime Power Management for PCI(e) bus devices. Alternatives are on
21672 Defaults to @samp{"on"}.
21676 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
21677 Same as @code{runtime-pm-ac} but on BAT mode.
21679 Defaults to @samp{"auto"}.
21683 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
21684 Runtime Power Management for all PCI(e) bus devices, except blacklisted
21687 Defaults to @samp{#t}.
21691 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
21692 Exclude specified PCI(e) device addresses from Runtime Power Management.
21694 Defaults to @samp{disabled}.
21698 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
21699 Exclude PCI(e) devices assigned to the specified drivers from Runtime
21704 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
21705 Enable USB autosuspend feature.
21707 Defaults to @samp{#t}.
21711 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
21712 Exclude specified devices from USB autosuspend.
21714 Defaults to @samp{disabled}.
21718 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
21719 Exclude WWAN devices from USB autosuspend.
21721 Defaults to @samp{#t}.
21725 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
21726 Include specified devices into USB autosuspend, even if they are already
21727 excluded by the driver or via @code{usb-blacklist-wwan?}.
21729 Defaults to @samp{disabled}.
21733 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
21734 Enable USB autosuspend before shutdown.
21736 Defaults to @samp{disabled}.
21740 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
21741 Restore radio device state (bluetooth, wifi, wwan) from previous
21742 shutdown on system startup.
21744 Defaults to @samp{#f}.
21749 @cindex CPU frequency scaling with thermald
21750 @subsubheading Thermald daemon
21752 The @code{(gnu services pm)} module provides an interface to
21753 thermald, a CPU frequency scaling service which helps prevent overheating.
21755 @defvr {Scheme Variable} thermald-service-type
21756 This is the service type for
21757 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
21758 Thermal Daemon, which is responsible for controlling the thermal state
21759 of processors and preventing overheating.
21762 @deftp {Data Type} thermald-configuration
21763 Data type representing the configuration of @code{thermald-service-type}.
21766 @item @code{ignore-cpuid-check?} (default: @code{#f})
21767 Ignore cpuid check for supported CPU models.
21769 @item @code{thermald} (default: @var{thermald})
21770 Package object of thermald.
21775 @node Audio Services
21776 @subsection Audio Services
21778 The @code{(gnu services audio)} module provides a service to start MPD
21779 (the Music Player Daemon).
21782 @subsubheading Music Player Daemon
21784 The Music Player Daemon (MPD) is a service that can play music while
21785 being controlled from the local machine or over the network by a variety
21788 The following example shows how one might run @code{mpd} as user
21789 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
21792 (service mpd-service-type
21798 @defvr {Scheme Variable} mpd-service-type
21799 The service type for @command{mpd}
21802 @deftp {Data Type} mpd-configuration
21803 Data type representing the configuration of @command{mpd}.
21806 @item @code{user} (default: @code{"mpd"})
21807 The user to run mpd as.
21809 @item @code{music-dir} (default: @code{"~/Music"})
21810 The directory to scan for music files.
21812 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
21813 The directory to store playlists.
21815 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
21816 The location of the music database.
21818 @item @code{state-file} (default: @code{"~/.mpd/state"})
21819 The location of the file that stores current MPD's state.
21821 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
21822 The location of the sticker database.
21824 @item @code{port} (default: @code{"6600"})
21825 The port to run mpd on.
21827 @item @code{address} (default: @code{"any"})
21828 The address that mpd will bind to. To use a Unix domain socket,
21829 an absolute path can be specified here.
21834 @node Virtualization Services
21835 @subsection Virtualization services
21837 The @code{(gnu services virtualization)} module provides services for
21838 the libvirt and virtlog daemons, as well as other virtualization-related
21841 @subsubheading Libvirt daemon
21842 @code{libvirtd} is the server side daemon component of the libvirt
21843 virtualization management system. This daemon runs on host servers
21844 and performs required management tasks for virtualized guests.
21846 @deffn {Scheme Variable} libvirt-service-type
21847 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
21848 Its value must be a @code{libvirt-configuration}.
21851 (service libvirt-service-type
21852 (libvirt-configuration
21853 (unix-sock-group "libvirt")
21854 (tls-port "16555")))
21858 @c Auto-generated with (generate-libvirt-documentation)
21859 Available @code{libvirt-configuration} fields are:
21861 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
21866 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
21867 Flag listening for secure TLS connections on the public TCP/IP port.
21868 must set @code{listen} for this to have any effect.
21870 It is necessary to setup a CA and issue server certificates before using
21873 Defaults to @samp{#t}.
21877 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
21878 Listen for unencrypted TCP connections on the public TCP/IP port. must
21879 set @code{listen} for this to have any effect.
21881 Using the TCP socket requires SASL authentication by default. Only SASL
21882 mechanisms which support data encryption are allowed. This is
21883 DIGEST_MD5 and GSSAPI (Kerberos5)
21885 Defaults to @samp{#f}.
21889 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
21890 Port for accepting secure TLS connections This can be a port number, or
21893 Defaults to @samp{"16514"}.
21897 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
21898 Port for accepting insecure TCP connections This can be a port number,
21901 Defaults to @samp{"16509"}.
21905 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
21906 IP address or hostname used for client connections.
21908 Defaults to @samp{"0.0.0.0"}.
21912 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
21913 Flag toggling mDNS advertisement of the libvirt service.
21915 Alternatively can disable for all services on a host by stopping the
21918 Defaults to @samp{#f}.
21922 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
21923 Default mDNS advertisement name. This must be unique on the immediate
21926 Defaults to @samp{"Virtualization Host <hostname>"}.
21930 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
21931 UNIX domain socket group ownership. This can be used to allow a
21932 'trusted' set of users access to management capabilities without
21935 Defaults to @samp{"root"}.
21939 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
21940 UNIX socket permissions for the R/O socket. This is used for monitoring
21943 Defaults to @samp{"0777"}.
21947 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
21948 UNIX socket permissions for the R/W socket. Default allows only root.
21949 If PolicyKit is enabled on the socket, the default will change to allow
21950 everyone (eg, 0777)
21952 Defaults to @samp{"0770"}.
21956 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
21957 UNIX socket permissions for the admin socket. Default allows only owner
21958 (root), do not change it unless you are sure to whom you are exposing
21961 Defaults to @samp{"0777"}.
21965 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
21966 The directory in which sockets will be found/created.
21968 Defaults to @samp{"/var/run/libvirt"}.
21972 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
21973 Authentication scheme for UNIX read-only sockets. By default socket
21974 permissions allow anyone to connect
21976 Defaults to @samp{"polkit"}.
21980 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
21981 Authentication scheme for UNIX read-write sockets. By default socket
21982 permissions only allow root. If PolicyKit support was compiled into
21983 libvirt, the default will be to use 'polkit' auth.
21985 Defaults to @samp{"polkit"}.
21989 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
21990 Authentication scheme for TCP sockets. If you don't enable SASL, then
21991 all TCP traffic is cleartext. Don't do this outside of a dev/test
21994 Defaults to @samp{"sasl"}.
21998 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
21999 Authentication scheme for TLS sockets. TLS sockets already have
22000 encryption provided by the TLS layer, and limited authentication is done
22003 It is possible to make use of any SASL authentication mechanism as well,
22004 by using 'sasl' for this option
22006 Defaults to @samp{"none"}.
22010 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
22011 API access control scheme.
22013 By default an authenticated user is allowed access to all APIs. Access
22014 drivers can place restrictions on this.
22016 Defaults to @samp{()}.
22020 @deftypevr {@code{libvirt-configuration} parameter} string key-file
22021 Server key file path. If set to an empty string, then no private key is
22024 Defaults to @samp{""}.
22028 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
22029 Server key file path. If set to an empty string, then no certificate is
22032 Defaults to @samp{""}.
22036 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
22037 Server key file path. If set to an empty string, then no CA certificate
22040 Defaults to @samp{""}.
22044 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
22045 Certificate revocation list path. If set to an empty string, then no
22048 Defaults to @samp{""}.
22052 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
22053 Disable verification of our own server certificates.
22055 When libvirtd starts it performs some sanity checks against its own
22058 Defaults to @samp{#f}.
22062 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
22063 Disable verification of client certificates.
22065 Client certificate verification is the primary authentication mechanism.
22066 Any client which does not present a certificate signed by the CA will be
22069 Defaults to @samp{#f}.
22073 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
22074 Whitelist of allowed x509 Distinguished Name.
22076 Defaults to @samp{()}.
22080 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
22081 Whitelist of allowed SASL usernames. The format for username depends on
22082 the SASL authentication mechanism.
22084 Defaults to @samp{()}.
22088 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
22089 Override the compile time default TLS priority string. The default is
22090 usually "NORMAL" unless overridden at build time. Only set this is it
22091 is desired for libvirt to deviate from the global default settings.
22093 Defaults to @samp{"NORMAL"}.
22097 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
22098 Maximum number of concurrent client connections to allow over all
22101 Defaults to @samp{5000}.
22105 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
22106 Maximum length of queue of connections waiting to be accepted by the
22107 daemon. Note, that some protocols supporting retransmission may obey
22108 this so that a later reattempt at connection succeeds.
22110 Defaults to @samp{1000}.
22114 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
22115 Maximum length of queue of accepted but not yet authenticated clients.
22116 Set this to zero to turn this feature off
22118 Defaults to @samp{20}.
22122 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
22123 Number of workers to start up initially.
22125 Defaults to @samp{5}.
22129 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
22130 Maximum number of worker threads.
22132 If the number of active clients exceeds @code{min-workers}, then more
22133 threads are spawned, up to max_workers limit. Typically you'd want
22134 max_workers to equal maximum number of clients allowed.
22136 Defaults to @samp{20}.
22140 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
22141 Number of priority workers. If all workers from above pool are stuck,
22142 some calls marked as high priority (notably domainDestroy) can be
22143 executed in this pool.
22145 Defaults to @samp{5}.
22149 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
22150 Total global limit on concurrent RPC calls.
22152 Defaults to @samp{20}.
22156 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
22157 Limit on concurrent requests from a single client connection. To avoid
22158 one client monopolizing the server this should be a small fraction of
22159 the global max_requests and max_workers parameter.
22161 Defaults to @samp{5}.
22165 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
22166 Same as @code{min-workers} but for the admin interface.
22168 Defaults to @samp{1}.
22172 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
22173 Same as @code{max-workers} but for the admin interface.
22175 Defaults to @samp{5}.
22179 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
22180 Same as @code{max-clients} but for the admin interface.
22182 Defaults to @samp{5}.
22186 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
22187 Same as @code{max-queued-clients} but for the admin interface.
22189 Defaults to @samp{5}.
22193 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
22194 Same as @code{max-client-requests} but for the admin interface.
22196 Defaults to @samp{5}.
22200 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
22201 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22203 Defaults to @samp{3}.
22207 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
22210 A filter allows to select a different logging level for a given category
22211 of logs The format for a filter is one of:
22222 where @code{name} is a string which is matched against the category
22223 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22224 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22225 be a substring of the full category name, in order to match multiple
22226 similar categories), the optional "+" prefix tells libvirt to log stack
22227 trace for each message matching name, and @code{x} is the minimal level
22228 where matching messages should be logged:
22245 Multiple filters can be defined in a single filters statement, they just
22246 need to be separated by spaces.
22248 Defaults to @samp{"3:remote 4:event"}.
22252 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
22255 An output is one of the places to save logging information. The format
22256 for an output can be:
22260 output goes to stderr
22262 @item x:syslog:name
22263 use syslog for the output and use the given name as the ident
22265 @item x:file:file_path
22266 output to a file, with the given filepath
22269 output to journald logging system
22273 In all case the x prefix is the minimal level, acting as a filter
22290 Multiple outputs can be defined, they just need to be separated by
22293 Defaults to @samp{"3:stderr"}.
22297 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
22298 Allows usage of the auditing subsystem to be altered
22302 0: disable all auditing
22305 1: enable auditing, only if enabled on host
22308 2: enable auditing, and exit if disabled on host.
22312 Defaults to @samp{1}.
22316 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
22317 Send audit messages via libvirt logging infrastructure.
22319 Defaults to @samp{#f}.
22323 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
22324 Host UUID. UUID must not have all digits be the same.
22326 Defaults to @samp{""}.
22330 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
22331 Source to read host UUID.
22335 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
22338 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
22342 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
22345 Defaults to @samp{"smbios"}.
22349 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
22350 A keepalive message is sent to a client after @code{keepalive_interval}
22351 seconds of inactivity to check if the client is still responding. If
22352 set to -1, libvirtd will never send keepalive requests; however clients
22353 can still send them and the daemon will send responses.
22355 Defaults to @samp{5}.
22359 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
22360 Maximum number of keepalive messages that are allowed to be sent to the
22361 client without getting any response before the connection is considered
22364 In other words, the connection is automatically closed approximately
22365 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
22366 the last message received from the client. When @code{keepalive-count}
22367 is set to 0, connections will be automatically closed after
22368 @code{keepalive-interval} seconds of inactivity without sending any
22369 keepalive messages.
22371 Defaults to @samp{5}.
22375 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
22376 Same as above but for admin interface.
22378 Defaults to @samp{5}.
22382 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
22383 Same as above but for admin interface.
22385 Defaults to @samp{5}.
22389 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
22390 Timeout for Open vSwitch calls.
22392 The @code{ovs-vsctl} utility is used for the configuration and its
22393 timeout option is set by default to 5 seconds to avoid potential
22394 infinite waits blocking libvirt.
22396 Defaults to @samp{5}.
22400 @c %end of autogenerated docs
22402 @subsubheading Virtlog daemon
22403 The virtlogd service is a server side daemon component of libvirt that is
22404 used to manage logs from virtual machine consoles.
22406 This daemon is not used directly by libvirt client applications, rather it
22407 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
22408 standalone daemon, the main @code{libvirtd} daemon can be restarted without
22409 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
22410 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
22412 @deffn {Scheme Variable} virtlog-service-type
22413 This is the type of the virtlog daemon.
22414 Its value must be a @code{virtlog-configuration}.
22417 (service virtlog-service-type
22418 (virtlog-configuration
22419 (max-clients 1000)))
22423 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
22424 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22426 Defaults to @samp{3}.
22430 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
22433 A filter allows to select a different logging level for a given category
22434 of logs The format for a filter is one of:
22445 where @code{name} is a string which is matched against the category
22446 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22447 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22448 be a substring of the full category name, in order to match multiple
22449 similar categories), the optional "+" prefix tells libvirt to log stack
22450 trace for each message matching name, and @code{x} is the minimal level
22451 where matching messages should be logged:
22468 Multiple filters can be defined in a single filters statement, they just
22469 need to be separated by spaces.
22471 Defaults to @samp{"3:remote 4:event"}.
22475 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
22478 An output is one of the places to save logging information The format
22479 for an output can be:
22483 output goes to stderr
22485 @item x:syslog:name
22486 use syslog for the output and use the given name as the ident
22488 @item x:file:file_path
22489 output to a file, with the given filepath
22492 output to journald logging system
22496 In all case the x prefix is the minimal level, acting as a filter
22513 Multiple outputs can be defined, they just need to be separated by
22516 Defaults to @samp{"3:stderr"}.
22520 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
22521 Maximum number of concurrent client connections to allow over all
22524 Defaults to @samp{1024}.
22528 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
22529 Maximum file size before rolling over.
22531 Defaults to @samp{2MB}
22535 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
22536 Maximum number of backup files to keep.
22538 Defaults to @samp{3}
22542 @subsubheading Transparent Emulation with QEMU
22545 @cindex @code{binfmt_misc}
22546 @code{qemu-binfmt-service-type} provides support for transparent
22547 emulation of program binaries built for different architectures---e.g.,
22548 it allows you to transparently execute an ARMv7 program on an x86_64
22549 machine. It achieves this by combining the @uref{https://www.qemu.org,
22550 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
22552 @defvr {Scheme Variable} qemu-binfmt-service-type
22553 This is the type of the QEMU/binfmt service for transparent emulation.
22554 Its value must be a @code{qemu-binfmt-configuration} object, which
22555 specifies the QEMU package to use as well as the architecture we want to
22559 (service qemu-binfmt-service-type
22560 (qemu-binfmt-configuration
22561 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
22564 In this example, we enable transparent emulation for the ARM and aarch64
22565 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
22566 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
22567 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
22570 @deftp {Data Type} qemu-binfmt-configuration
22571 This is the configuration for the @code{qemu-binfmt} service.
22574 @item @code{platforms} (default: @code{'()})
22575 The list of emulated QEMU platforms. Each item must be a @dfn{platform
22576 object} as returned by @code{lookup-qemu-platforms} (see below).
22578 @item @code{guix-support?} (default: @code{#f})
22579 When it is true, QEMU and all its dependencies are added to the build
22580 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
22581 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
22582 handlers to be used within the build environment, which in turn means
22583 that you can transparently build programs for another architecture.
22585 For example, let's suppose you're on an x86_64 machine and you have this
22589 (service qemu-binfmt-service-type
22590 (qemu-binfmt-configuration
22591 (platforms (lookup-qemu-platforms "arm"))
22592 (guix-support? #t)))
22598 guix build -s armhf-linux inkscape
22602 and it will build Inkscape for ARMv7 @emph{as if it were a native
22603 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
22604 if you'd like to test a package build for an architecture you don't have
22607 @item @code{qemu} (default: @code{qemu})
22608 The QEMU package to use.
22612 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
22613 Return the list of QEMU platform objects corresponding to
22614 @var{platforms}@dots{}. @var{platforms} must be a list of strings
22615 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
22616 @code{"mips64el"}, and so on.
22619 @deffn {Scheme Procedure} qemu-platform? @var{obj}
22620 Return true if @var{obj} is a platform object.
22623 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
22624 Return the name of @var{platform}---a string such as @code{"arm"}.
22627 @node Version Control Services
22628 @subsection Version Control Services
22630 The @code{(gnu services version-control)} module provides a service to
22631 allow remote access to local Git repositories. There are three options:
22632 the @code{git-daemon-service}, which provides access to repositories via
22633 the @code{git://} unsecured TCP-based protocol, extending the
22634 @code{nginx} web server to proxy some requests to
22635 @code{git-http-backend}, or providing a web interface with
22636 @code{cgit-service-type}.
22638 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
22640 Return a service that runs @command{git daemon}, a simple TCP server to
22641 expose repositories over the Git protocol for anonymous access.
22643 The optional @var{config} argument should be a
22644 @code{<git-daemon-configuration>} object, by default it allows read-only
22645 access to exported@footnote{By creating the magic file
22646 "git-daemon-export-ok" in the repository directory.} repositories under
22651 @deftp {Data Type} git-daemon-configuration
22652 Data type representing the configuration for @code{git-daemon-service}.
22655 @item @code{package} (default: @var{git})
22656 Package object of the Git distributed version control system.
22658 @item @code{export-all?} (default: @var{#f})
22659 Whether to allow access for all Git repositories, even if they do not
22660 have the @file{git-daemon-export-ok} file.
22662 @item @code{base-path} (default: @file{/srv/git})
22663 Whether to remap all the path requests as relative to the given path.
22664 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
22665 then if you later try to pull @code{git://example.com/hello.git}, git
22666 daemon will interpret the path as @code{/srv/git/hello.git}.
22668 @item @code{user-path} (default: @var{#f})
22669 Whether to allow @code{~user} notation to be used in requests. When
22670 specified with empty string, requests to @code{git://host/~alice/foo} is
22671 taken as a request to access @code{foo} repository in the home directory
22672 of user @code{alice}. If @var{(user-path "path")} is specified, the
22673 same request is taken as a request to access @code{path/foo} repository
22674 in the home directory of user @code{alice}.
22676 @item @code{listen} (default: @var{'()})
22677 Whether to listen on specific IP addresses or hostnames, defaults to
22680 @item @code{port} (default: @var{#f})
22681 Whether to listen on an alternative port, which defaults to 9418.
22683 @item @code{whitelist} (default: @var{'()})
22684 If not empty, only allow access to this list of directories.
22686 @item @code{extra-options} (default: @var{'()})
22687 Extra options will be passed to @code{git daemon}, please run
22688 @command{man git-daemon} for more information.
22693 The @code{git://} protocol lacks authentication. When you pull from a
22694 repository fetched via @code{git://}, you don't know that the data you
22695 receive was modified is really coming from the specified host, and you
22696 have your connection is subject to eavesdropping. It's better to use an
22697 authenticated and encrypted transport, such as @code{https}. Although Git allows you
22698 to serve repositories using unsophisticated file-based web servers,
22699 there is a faster protocol implemented by the @code{git-http-backend}
22700 program. This program is the back-end of a proper Git web service. It
22701 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
22702 on running the necessary @code{fcgiwrap} daemon.
22704 Guix has a separate configuration data type for serving Git repositories
22707 @deftp {Data Type} git-http-configuration
22708 Data type representing the configuration for @code{git-http-service}.
22711 @item @code{package} (default: @var{git})
22712 Package object of the Git distributed version control system.
22714 @item @code{git-root} (default: @file{/srv/git})
22715 Directory containing the Git repositories to expose to the world.
22717 @item @code{export-all?} (default: @var{#f})
22718 Whether to expose access for all Git repositories in @var{git-root},
22719 even if they do not have the @file{git-daemon-export-ok} file.
22721 @item @code{uri-path} (default: @file{/git/})
22722 Path prefix for Git access. With the default @code{/git/} prefix, this
22723 will map @code{http://@var{server}/git/@var{repo}.git} to
22724 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
22725 with this prefix are not passed on to this Git instance.
22727 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
22728 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
22733 There is no @code{git-http-service-type}, currently; instead you can
22734 create an @code{nginx-location-configuration} from a
22735 @code{git-http-configuration} and then add that location to a web
22738 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
22739 [config=(git-http-configuration)]
22740 Compute an @code{nginx-location-configuration} that corresponds to the
22741 given Git http configuration. An example nginx service definition to
22742 serve the default @file{/srv/git} over HTTPS might be:
22745 (service nginx-service-type
22746 (nginx-configuration
22749 (nginx-server-configuration
22750 (listen '("443 ssl"))
22751 (server-name "git.my-host.org")
22753 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
22754 (ssl-certificate-key
22755 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
22758 (git-http-nginx-location-configuration
22759 (git-http-configuration (uri-path "/"))))))))))
22762 This example assumes that you are using Let's Encrypt to get your TLS
22763 certificate. @xref{Certificate Services}. The default @code{certbot}
22764 service will redirect all HTTP traffic on @code{git.my-host.org} to
22765 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
22766 system services. @xref{Web Services}.
22769 @subsubheading Cgit Service
22771 @cindex Cgit service
22772 @cindex Git, web interface
22773 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
22774 repositories written in C.
22776 The following example will configure the service with default values.
22777 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
22780 (service cgit-service-type)
22783 The @code{file-object} type designates either a file-like object
22784 (@pxref{G-Expressions, file-like objects}) or a string.
22786 @c %start of fragment
22788 Available @code{cgit-configuration} fields are:
22790 @deftypevr {@code{cgit-configuration} parameter} package package
22795 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
22796 NGINX configuration.
22800 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
22801 Specifies a command which will be invoked to format the content of about
22802 pages (both top-level and for each repository).
22804 Defaults to @samp{""}.
22808 @deftypevr {@code{cgit-configuration} parameter} string agefile
22809 Specifies a path, relative to each repository path, which can be used to
22810 specify the date and time of the youngest commit in the repository.
22812 Defaults to @samp{""}.
22816 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
22817 Specifies a command that will be invoked for authenticating repository
22820 Defaults to @samp{""}.
22824 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
22825 Flag which, when set to @samp{age}, enables date ordering in the branch
22826 ref list, and when set @samp{name} enables ordering by branch name.
22828 Defaults to @samp{"name"}.
22832 @deftypevr {@code{cgit-configuration} parameter} string cache-root
22833 Path used to store the cgit cache entries.
22835 Defaults to @samp{"/var/cache/cgit"}.
22839 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
22840 Number which specifies the time-to-live, in minutes, for the cached
22841 version of repository pages accessed with a fixed SHA1.
22843 Defaults to @samp{-1}.
22847 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
22848 Number which specifies the time-to-live, in minutes, for the cached
22849 version of repository pages accessed without a fixed SHA1.
22851 Defaults to @samp{5}.
22855 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
22856 Number which specifies the time-to-live, in minutes, for the cached
22857 version of the repository summary page.
22859 Defaults to @samp{5}.
22863 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
22864 Number which specifies the time-to-live, in minutes, for the cached
22865 version of the repository index page.
22867 Defaults to @samp{5}.
22871 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
22872 Number which specifies the time-to-live, in minutes, for the result of
22873 scanning a path for Git repositories.
22875 Defaults to @samp{15}.
22879 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
22880 Number which specifies the time-to-live, in minutes, for the cached
22881 version of the repository about page.
22883 Defaults to @samp{15}.
22887 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
22888 Number which specifies the time-to-live, in minutes, for the cached
22889 version of snapshots.
22891 Defaults to @samp{5}.
22895 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
22896 The maximum number of entries in the cgit cache. When set to @samp{0},
22897 caching is disabled.
22899 Defaults to @samp{0}.
22903 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
22904 Sort items in the repo list case sensitively.
22906 Defaults to @samp{#t}.
22910 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
22911 List of common prefixes which, when combined with a repository URL,
22912 generates valid clone URLs for the repository.
22914 Defaults to @samp{()}.
22918 @deftypevr {@code{cgit-configuration} parameter} list clone-url
22919 List of @code{clone-url} templates.
22921 Defaults to @samp{()}.
22925 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
22926 Command which will be invoked to format commit messages.
22928 Defaults to @samp{""}.
22932 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
22933 Flag which, when set to @samp{date}, enables strict date ordering in the
22934 commit log, and when set to @samp{topo} enables strict topological
22937 Defaults to @samp{"git log"}.
22941 @deftypevr {@code{cgit-configuration} parameter} file-object css
22942 URL which specifies the css document to include in all cgit pages.
22944 Defaults to @samp{"/share/cgit/cgit.css"}.
22948 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
22949 Specifies a command which will be invoked to format names and email
22950 address of committers, authors, and taggers, as represented in various
22951 places throughout the cgit interface.
22953 Defaults to @samp{""}.
22957 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
22958 Flag which, when set to @samp{#t}, will make cgit generate a HTML
22959 fragment suitable for embedding in other HTML pages.
22961 Defaults to @samp{#f}.
22965 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
22966 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
22967 commit history graph to the left of the commit messages in the
22968 repository log page.
22970 Defaults to @samp{#f}.
22974 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
22975 Flag which, when set to @samp{#t}, allows all filter settings to be
22976 overridden in repository-specific cgitrc files.
22978 Defaults to @samp{#f}.
22982 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
22983 Flag which, when set to @samp{#t}, allows users to follow a file in the
22986 Defaults to @samp{#f}.
22990 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
22991 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
22994 Defaults to @samp{#t}.
22998 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
22999 Flag which, when set to @samp{#t}, will make cgit generate extra links
23000 "summary", "commit", "tree" for each repo in the repository index.
23002 Defaults to @samp{#f}.
23006 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
23007 Flag which, when set to @samp{#t}, will make cgit display the owner of
23008 each repo in the repository index.
23010 Defaults to @samp{#t}.
23014 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
23015 Flag which, when set to @samp{#t}, will make cgit print the number of
23016 modified files for each commit on the repository log page.
23018 Defaults to @samp{#f}.
23022 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
23023 Flag which, when set to @samp{#t}, will make cgit print the number of
23024 added and removed lines for each commit on the repository log page.
23026 Defaults to @samp{#f}.
23030 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
23031 Flag which, when set to @code{#t}, will make cgit display remote
23032 branches in the summary and refs views.
23034 Defaults to @samp{#f}.
23038 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
23039 Flag which, when set to @code{1}, will make cgit use the subject of the
23040 parent commit as link text when generating links to parent commits in
23043 Defaults to @samp{#f}.
23047 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
23048 Flag which, when set to @samp{#t}, will make cgit use the subject of the
23049 parent commit as link text when generating links to parent commits in
23052 Defaults to @samp{#f}.
23056 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
23057 Flag which, when set to @samp{#t}, will make cgit generate linenumber
23058 links for plaintext blobs printed in the tree view.
23060 Defaults to @samp{#t}.
23064 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
23065 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
23066 set any repo specific settings.
23068 Defaults to @samp{#f}.
23072 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
23073 URL used as link to a shortcut icon for cgit.
23075 Defaults to @samp{"/favicon.ico"}.
23079 @deftypevr {@code{cgit-configuration} parameter} string footer
23080 The content of the file specified with this option will be included
23081 verbatim at the bottom of all pages (i.e.@: it replaces the standard
23082 "generated by..."@: message).
23084 Defaults to @samp{""}.
23088 @deftypevr {@code{cgit-configuration} parameter} string head-include
23089 The content of the file specified with this option will be included
23090 verbatim in the HTML HEAD section on all pages.
23092 Defaults to @samp{""}.
23096 @deftypevr {@code{cgit-configuration} parameter} string header
23097 The content of the file specified with this option will be included
23098 verbatim at the top of all pages.
23100 Defaults to @samp{""}.
23104 @deftypevr {@code{cgit-configuration} parameter} file-object include
23105 Name of a configfile to include before the rest of the current config-
23108 Defaults to @samp{""}.
23112 @deftypevr {@code{cgit-configuration} parameter} string index-header
23113 The content of the file specified with this option will be included
23114 verbatim above the repository index.
23116 Defaults to @samp{""}.
23120 @deftypevr {@code{cgit-configuration} parameter} string index-info
23121 The content of the file specified with this option will be included
23122 verbatim below the heading on the repository index page.
23124 Defaults to @samp{""}.
23128 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
23129 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
23130 in the servers timezone.
23132 Defaults to @samp{#f}.
23136 @deftypevr {@code{cgit-configuration} parameter} file-object logo
23137 URL which specifies the source of an image which will be used as a logo
23140 Defaults to @samp{"/share/cgit/cgit.png"}.
23144 @deftypevr {@code{cgit-configuration} parameter} string logo-link
23145 URL loaded when clicking on the cgit logo image.
23147 Defaults to @samp{""}.
23151 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
23152 Command which will be invoked to format the Owner column of the main
23155 Defaults to @samp{""}.
23159 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
23160 Number of items to display in atom feeds view.
23162 Defaults to @samp{10}.
23166 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
23167 Number of entries to list per page in "log" view.
23169 Defaults to @samp{50}.
23173 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
23174 Number of commit message characters to display in "log" view.
23176 Defaults to @samp{80}.
23180 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
23181 Specifies the number of entries to list per page on the repository index
23184 Defaults to @samp{50}.
23188 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
23189 Specifies the maximum number of repo description characters to display
23190 on the repository index page.
23192 Defaults to @samp{80}.
23196 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
23197 Specifies the maximum size of a blob to display HTML for in KBytes.
23199 Defaults to @samp{0}.
23203 @deftypevr {@code{cgit-configuration} parameter} string max-stats
23204 Maximum statistics period. Valid values are @samp{week},@samp{month},
23205 @samp{quarter} and @samp{year}.
23207 Defaults to @samp{""}.
23211 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
23212 Mimetype for the specified filename extension.
23214 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
23215 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
23216 "image/png") (svg "image/svg+xml"))}.
23220 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
23221 Specifies the file to use for automatic mimetype lookup.
23223 Defaults to @samp{""}.
23227 @deftypevr {@code{cgit-configuration} parameter} string module-link
23228 Text which will be used as the formatstring for a hyperlink when a
23229 submodule is printed in a directory listing.
23231 Defaults to @samp{""}.
23235 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
23236 If set to the value @samp{#t} caching will be disabled.
23238 Defaults to @samp{#f}.
23242 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
23243 If set to @samp{#t} showing full author email addresses will be
23246 Defaults to @samp{#f}.
23250 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
23251 Flag which, when set to @samp{#t}, will make cgit omit the standard
23252 header on all pages.
23254 Defaults to @samp{#f}.
23258 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
23259 A list of subdirectories inside of @code{repository-directory}, relative
23260 to it, that should loaded as Git repositories. An empty list means that
23261 all subdirectories will be loaded.
23263 Defaults to @samp{()}.
23267 @deftypevr {@code{cgit-configuration} parameter} file-object readme
23268 Text which will be used as default value for @code{cgit-repo-readme}.
23270 Defaults to @samp{""}.
23274 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
23275 If set to @code{#t} and @code{repository-directory} is enabled, if any
23276 repositories are found with a suffix of @code{.git}, this suffix will be
23277 removed for the URL and name.
23279 Defaults to @samp{#f}.
23283 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
23284 Maximum number of files to consider when detecting renames.
23286 Defaults to @samp{-1}.
23290 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
23291 The way in which repositories in each section are sorted.
23293 Defaults to @samp{""}.
23297 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
23298 Text used as content for the @code{robots} meta-tag.
23300 Defaults to @samp{("noindex" "nofollow")}.
23304 @deftypevr {@code{cgit-configuration} parameter} string root-desc
23305 Text printed below the heading on the repository index page.
23307 Defaults to @samp{"a fast webinterface for the git dscm"}.
23311 @deftypevr {@code{cgit-configuration} parameter} string root-readme
23312 The content of the file specified with this option will be included
23313 verbatim below thef "about" link on the repository index page.
23315 Defaults to @samp{""}.
23319 @deftypevr {@code{cgit-configuration} parameter} string root-title
23320 Text printed as heading on the repository index page.
23322 Defaults to @samp{""}.
23326 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
23327 If set to @samp{#t} and repository-directory is enabled,
23328 repository-directory will recurse into directories whose name starts
23329 with a period. Otherwise, repository-directory will stay away from such
23330 directories, considered as "hidden". Note that this does not apply to
23331 the ".git" directory in non-bare repos.
23333 Defaults to @samp{#f}.
23337 @deftypevr {@code{cgit-configuration} parameter} list snapshots
23338 Text which specifies the default set of snapshot formats that cgit
23339 generates links for.
23341 Defaults to @samp{()}.
23345 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
23346 Name of the directory to scan for repositories (represents
23349 Defaults to @samp{"/srv/git"}.
23353 @deftypevr {@code{cgit-configuration} parameter} string section
23354 The name of the current repository section - all repositories defined
23355 after this option will inherit the current section name.
23357 Defaults to @samp{""}.
23361 @deftypevr {@code{cgit-configuration} parameter} string section-sort
23362 Flag which, when set to @samp{1}, will sort the sections on the
23363 repository listing by name.
23365 Defaults to @samp{""}.
23369 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
23370 A number which, if defined prior to repository-directory, specifies how
23371 many path elements from each repo path to use as a default section name.
23373 Defaults to @samp{0}.
23377 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
23378 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
23381 Defaults to @samp{#f}.
23385 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
23386 Specifies a command which will be invoked to format plaintext blobs in
23389 Defaults to @samp{""}.
23393 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
23394 Specifies the number of branches to display in the repository "summary"
23397 Defaults to @samp{10}.
23401 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
23402 Specifies the number of log entries to display in the repository
23405 Defaults to @samp{10}.
23409 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
23410 Specifies the number of tags to display in the repository "summary"
23413 Defaults to @samp{10}.
23417 @deftypevr {@code{cgit-configuration} parameter} string strict-export
23418 Filename which, if specified, needs to be present within the repository
23419 for cgit to allow access to that repository.
23421 Defaults to @samp{""}.
23425 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
23426 URL which, if specified, will be used as root for all cgit links.
23428 Defaults to @samp{"/"}.
23432 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
23433 A list of @dfn{cgit-repo} records to use with config.
23435 Defaults to @samp{()}.
23437 Available @code{repository-cgit-configuration} fields are:
23439 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
23440 A mask of snapshot formats for this repo that cgit generates links for,
23441 restricted by the global @code{snapshots} setting.
23443 Defaults to @samp{()}.
23447 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
23448 Override the default @code{source-filter}.
23450 Defaults to @samp{""}.
23454 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
23455 The relative URL used to access the repository.
23457 Defaults to @samp{""}.
23461 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
23462 Override the default @code{about-filter}.
23464 Defaults to @samp{""}.
23468 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
23469 Flag which, when set to @samp{age}, enables date ordering in the branch
23470 ref list, and when set to @samp{name} enables ordering by branch name.
23472 Defaults to @samp{""}.
23476 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
23477 A list of URLs which can be used to clone repo.
23479 Defaults to @samp{()}.
23483 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
23484 Override the default @code{commit-filter}.
23486 Defaults to @samp{""}.
23490 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
23491 Flag which, when set to @samp{date}, enables strict date ordering in the
23492 commit log, and when set to @samp{topo} enables strict topological
23495 Defaults to @samp{""}.
23499 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
23500 The name of the default branch for this repository. If no such branch
23501 exists in the repository, the first branch name (when sorted) is used as
23502 default instead. By default branch pointed to by HEAD, or "master" if
23503 there is no suitable HEAD.
23505 Defaults to @samp{""}.
23509 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
23510 The value to show as repository description.
23512 Defaults to @samp{""}.
23516 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
23517 The value to show as repository homepage.
23519 Defaults to @samp{""}.
23523 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
23524 Override the default @code{email-filter}.
23526 Defaults to @samp{""}.
23530 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
23531 A flag which can be used to disable the global setting
23532 @code{enable-commit-graph?}.
23534 Defaults to @samp{disabled}.
23538 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
23539 A flag which can be used to disable the global setting
23540 @code{enable-log-filecount?}.
23542 Defaults to @samp{disabled}.
23546 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
23547 A flag which can be used to disable the global setting
23548 @code{enable-log-linecount?}.
23550 Defaults to @samp{disabled}.
23554 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
23555 Flag which, when set to @code{#t}, will make cgit display remote
23556 branches in the summary and refs views.
23558 Defaults to @samp{disabled}.
23562 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
23563 A flag which can be used to override the global setting
23564 @code{enable-subject-links?}.
23566 Defaults to @samp{disabled}.
23570 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
23571 A flag which can be used to override the global setting
23572 @code{enable-html-serving?}.
23574 Defaults to @samp{disabled}.
23578 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
23579 Flag which, when set to @code{#t}, hides the repository from the
23582 Defaults to @samp{#f}.
23586 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
23587 Flag which, when set to @samp{#t}, ignores the repository.
23589 Defaults to @samp{#f}.
23593 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
23594 URL which specifies the source of an image which will be used as a logo
23595 on this repo’s pages.
23597 Defaults to @samp{""}.
23601 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
23602 URL loaded when clicking on the cgit logo image.
23604 Defaults to @samp{""}.
23608 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
23609 Override the default @code{owner-filter}.
23611 Defaults to @samp{""}.
23615 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
23616 Text which will be used as the formatstring for a hyperlink when a
23617 submodule is printed in a directory listing. The arguments for the
23618 formatstring are the path and SHA1 of the submodule commit.
23620 Defaults to @samp{""}.
23624 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
23625 Text which will be used as the formatstring for a hyperlink when a
23626 submodule with the specified subdirectory path is printed in a directory
23629 Defaults to @samp{()}.
23633 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
23634 Override the default maximum statistics period.
23636 Defaults to @samp{""}.
23640 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
23641 The value to show as repository name.
23643 Defaults to @samp{""}.
23647 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
23648 A value used to identify the owner of the repository.
23650 Defaults to @samp{""}.
23654 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
23655 An absolute path to the repository directory.
23657 Defaults to @samp{""}.
23661 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
23662 A path (relative to repo) which specifies a file to include verbatim as
23663 the "About" page for this repo.
23665 Defaults to @samp{""}.
23669 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
23670 The name of the current repository section - all repositories defined
23671 after this option will inherit the current section name.
23673 Defaults to @samp{""}.
23677 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
23678 Extra options will be appended to cgitrc file.
23680 Defaults to @samp{()}.
23686 @deftypevr {@code{cgit-configuration} parameter} list extra-options
23687 Extra options will be appended to cgitrc file.
23689 Defaults to @samp{()}.
23694 @c %end of fragment
23696 However, it could be that you just want to get a @code{cgitrc} up and
23697 running. In that case, you can pass an @code{opaque-cgit-configuration}
23698 as a record to @code{cgit-service-type}. As its name indicates, an
23699 opaque configuration does not have easy reflective capabilities.
23701 Available @code{opaque-cgit-configuration} fields are:
23703 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
23707 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
23708 The contents of the @code{cgitrc}, as a string.
23711 For example, if your @code{cgitrc} is just the empty string, you
23712 could instantiate a cgit service like this:
23715 (service cgit-service-type
23716 (opaque-cgit-configuration
23720 @subsubheading Gitolite Service
23722 @cindex Gitolite service
23723 @cindex Git, hosting
23724 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
23725 repositories on a central server.
23727 Gitolite can handle multiple repositories and users, and supports flexible
23728 configuration of the permissions for the users on the repositories.
23730 The following example will configure Gitolite using the default @code{git}
23731 user, and the provided SSH public key.
23734 (service gitolite-service-type
23735 (gitolite-configuration
23736 (admin-pubkey (plain-file
23738 "ssh-rsa AAAA... guix@@example.com"))))
23741 Gitolite is configured through a special admin repository which you can clone,
23742 for example, if you setup Gitolite on @code{example.com}, you would run the
23743 following command to clone the admin repository.
23746 git clone git@@example.com:gitolite-admin
23749 When the Gitolite service is activated, the provided @code{admin-pubkey} will
23750 be inserted in to the @file{keydir} directory in the gitolite-admin
23751 repository. If this results in a change in the repository, it will be
23752 committed using the message ``gitolite setup by GNU Guix''.
23754 @deftp {Data Type} gitolite-configuration
23755 Data type representing the configuration for @code{gitolite-service-type}.
23758 @item @code{package} (default: @var{gitolite})
23759 Gitolite package to use.
23761 @item @code{user} (default: @var{git})
23762 User to use for Gitolite. This will be user that you use when accessing
23765 @item @code{group} (default: @var{git})
23766 Group to use for Gitolite.
23768 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
23769 Directory in which to store the Gitolite configuration and repositories.
23771 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
23772 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
23773 representing the configuration for Gitolite.
23775 @item @code{admin-pubkey} (default: @var{#f})
23776 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
23777 setup Gitolite. This will be inserted in to the @file{keydir} directory
23778 within the gitolite-admin repository.
23780 To specify the SSH key as a string, use the @code{plain-file} function.
23783 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
23789 @deftp {Data Type} gitolite-rc-file
23790 Data type representing the Gitolite RC file.
23793 @item @code{umask} (default: @code{#o0077})
23794 This controls the permissions Gitolite sets on the repositories and their
23797 A value like @code{#o0027} will give read access to the group used by Gitolite
23798 (by default: @code{git}). This is necessary when using Gitolite with software
23799 like cgit or gitweb.
23801 @item @code{git-config-keys} (default: @code{""})
23802 Gitolite allows you to set git config values using the "config" keyword. This
23803 setting allows control over the config keys to accept.
23805 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
23806 Set the role names allowed to be used by users running the perms command.
23808 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
23809 This setting controls the commands and features to enable within Gitolite.
23815 @node Game Services
23816 @subsection Game Services
23818 @subsubheading The Battle for Wesnoth Service
23820 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
23821 based tactical strategy game, with several single player campaigns, and
23822 multiplayer games (both networked and local).
23824 @defvar {Scheme Variable} wesnothd-service-type
23825 Service type for the wesnothd service. Its value must be a
23826 @code{wesnothd-configuration} object. To run wesnothd in the default
23827 configuration, instantiate it as:
23830 (service wesnothd-service-type)
23834 @deftp {Data Type} wesnothd-configuration
23835 Data type representing the configuration of @command{wesnothd}.
23838 @item @code{package} (default: @code{wesnoth-server})
23839 The wesnoth server package to use.
23841 @item @code{port} (default: @code{15000})
23842 The port to bind the server to.
23846 @node Miscellaneous Services
23847 @subsection Miscellaneous Services
23849 @cindex fingerprint
23850 @subsubheading Fingerprint Service
23852 The @code{(gnu services authentication)} module provides a DBus service to
23853 read and identify fingerprints via a fingerprint sensor.
23855 @defvr {Scheme Variable} fprintd-service-type
23856 The service type for @command{fprintd}, which provides the fingerprint
23857 reading capability.
23860 (service fprintd-service-type)
23865 @subsubheading System Control Service
23867 The @code{(gnu services sysctl)} provides a service to configure kernel
23868 parameters at boot.
23870 @defvr {Scheme Variable} sysctl-service-type
23871 The service type for @command{sysctl}, which modifies kernel parameters
23872 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
23876 (service sysctl-service-type
23877 (sysctl-configuration
23878 (settings '(("net.ipv4.ip_forward" . "1")))))
23882 @deftp {Data Type} sysctl-configuration
23883 The data type representing the configuration of @command{sysctl}.
23886 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
23887 The @command{sysctl} executable to use.
23889 @item @code{settings} (default: @code{'()})
23890 An association list specifies kernel parameters and their values.
23895 @subsubheading PC/SC Smart Card Daemon Service
23897 The @code{(gnu services security-token)} module provides the following service
23898 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
23899 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
23900 manager that coordinates communications with smart card readers, smart cards
23901 and cryptographic tokens that are connected to the system.
23903 @defvr {Scheme Variable} pcscd-service-type
23904 Service type for the @command{pcscd} service. Its value must be a
23905 @code{pcscd-configuration} object. To run pcscd in the default
23906 configuration, instantiate it as:
23909 (service pcscd-service-type)
23913 @deftp {Data Type} pcscd-configuration
23914 The data type representing the configuration of @command{pcscd}.
23917 @item @code{pcsc-lite} (default: @code{pcsc-lite})
23918 The pcsc-lite package that provides pcscd.
23919 @item @code{usb-drivers} (default: @code{(list ccid)})
23920 List of packages that provide USB drivers to pcscd. Drivers are expected to be
23921 under @file{pcsc/drivers} in the store directory of the package.
23926 @subsubheading Lirc Service
23928 The @code{(gnu services lirc)} module provides the following service.
23930 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
23931 [#:device #f] [#:driver #f] [#:config-file #f] @
23932 [#:extra-options '()]
23933 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
23934 decodes infrared signals from remote controls.
23936 Optionally, @var{device}, @var{driver} and @var{config-file}
23937 (configuration file name) may be specified. See @command{lircd} manual
23940 Finally, @var{extra-options} is a list of additional command-line options
23941 passed to @command{lircd}.
23945 @subsubheading Spice Service
23947 The @code{(gnu services spice)} module provides the following service.
23949 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
23950 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
23951 that enables sharing the clipboard with a vm and setting the guest display
23952 resolution when the graphical console window resizes.
23955 @cindex inputattach
23956 @subsubheading inputattach Service
23958 @cindex tablet input, for Xorg
23959 @cindex touchscreen input, for Xorg
23960 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
23961 use input devices such as Wacom tablets, touchscreens, or joysticks with the
23962 Xorg display server.
23964 @deffn {Scheme Variable} inputattach-service-type
23965 Type of a service that runs @command{inputattach} on a device and
23966 dispatches events from it.
23969 @deftp {Data Type} inputattach-configuration
23971 @item @code{device-type} (default: @code{"wacom"})
23972 The type of device to connect to. Run @command{inputattach --help}, from the
23973 @code{inputattach} package, to see the list of supported device types.
23975 @item @code{device} (default: @code{"/dev/ttyS0"})
23976 The device file to connect to the device.
23978 @item @code{log-file} (default: @code{#f})
23979 If true, this must be the name of a file to log messages to.
23983 @subsection Dictionary Services
23985 The @code{(gnu services dict)} module provides the following service:
23987 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
23988 Return a service that runs the @command{dicod} daemon, an implementation
23989 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
23991 The optional @var{config} argument specifies the configuration for
23992 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
23993 default it serves the GNU Collaborative International Dictonary of English.
23995 You can add @command{open localhost} to your @file{~/.dico} file to make
23996 @code{localhost} the default server for @command{dico} client
23997 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
24000 @deftp {Data Type} dicod-configuration
24001 Data type representing the configuration of dicod.
24004 @item @code{dico} (default: @var{dico})
24005 Package object of the GNU Dico dictionary server.
24007 @item @code{interfaces} (default: @var{'("localhost")})
24008 This is the list of IP addresses and ports and possibly socket file
24009 names to listen to (@pxref{Server Settings, @code{listen} directive,,
24010 dico, GNU Dico Manual}).
24012 @item @code{handlers} (default: @var{'()})
24013 List of @code{<dicod-handler>} objects denoting handlers (module instances).
24015 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
24016 List of @code{<dicod-database>} objects denoting dictionaries to be served.
24020 @deftp {Data Type} dicod-handler
24021 Data type representing a dictionary handler (module instance).
24025 Name of the handler (module instance).
24027 @item @code{module} (default: @var{#f})
24028 Name of the dicod module of the handler (instance). If it is @code{#f},
24029 the module has the same name as the handler.
24030 (@pxref{Modules,,, dico, GNU Dico Manual}).
24032 @item @code{options}
24033 List of strings or gexps representing the arguments for the module handler
24037 @deftp {Data Type} dicod-database
24038 Data type representing a dictionary database.
24042 Name of the database, will be used in DICT commands.
24044 @item @code{handler}
24045 Name of the dicod handler (module instance) used by this database
24046 (@pxref{Handlers,,, dico, GNU Dico Manual}).
24048 @item @code{complex?} (default: @var{#f})
24049 Whether the database configuration complex. The complex configuration
24050 will need a corresponding @code{<dicod-handler>} object, otherwise not.
24052 @item @code{options}
24053 List of strings or gexps representing the arguments for the database
24054 (@pxref{Databases,,, dico, GNU Dico Manual}).
24058 @defvr {Scheme Variable} %dicod-database:gcide
24059 A @code{<dicod-database>} object serving the GNU Collaborative International
24060 Dictionary of English using the @code{gcide} package.
24063 The following is an example @code{dicod-service} configuration.
24066 (dicod-service #:config
24067 (dicod-configuration
24068 (handlers (list (dicod-handler
24072 (list #~(string-append "dbdir=" #$wordnet))))))
24073 (databases (list (dicod-database
24076 (handler "wordnet")
24077 (options '("database=wn")))
24078 %dicod-database:gcide))))
24082 @subsubheading Docker Service
24084 The @code{(gnu services docker)} module provides the following service.
24086 @defvr {Scheme Variable} docker-service-type
24088 This is the type of the service that runs @url{https://www.docker.com,Docker},
24089 a daemon that can execute application bundles (sometimes referred to as
24090 ``containers'') in isolated environments.
24094 @deftp {Data Type} docker-configuration
24095 This is the data type representing the configuration of Docker and Containerd.
24099 @item @code{package} (default: @code{docker})
24100 The Docker package to use.
24102 @item @code{containerd} (default: @var{containerd})
24103 The Containerd package to use.
24108 @node Setuid Programs
24109 @section Setuid Programs
24111 @cindex setuid programs
24112 Some programs need to run with ``root'' privileges, even when they are
24113 launched by unprivileged users. A notorious example is the
24114 @command{passwd} program, which users can run to change their
24115 password, and which needs to access the @file{/etc/passwd} and
24116 @file{/etc/shadow} files---something normally restricted to root, for
24117 obvious security reasons. To address that, these executables are
24118 @dfn{setuid-root}, meaning that they always run with root privileges
24119 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
24120 for more info about the setuid mechanism.)
24122 The store itself @emph{cannot} contain setuid programs: that would be a
24123 security issue since any user on the system can write derivations that
24124 populate the store (@pxref{The Store}). Thus, a different mechanism is
24125 used: instead of changing the setuid bit directly on files that are in
24126 the store, we let the system administrator @emph{declare} which programs
24127 should be setuid root.
24129 The @code{setuid-programs} field of an @code{operating-system}
24130 declaration contains a list of G-expressions denoting the names of
24131 programs to be setuid-root (@pxref{Using the Configuration System}).
24132 For instance, the @command{passwd} program, which is part of the Shadow
24133 package, can be designated by this G-expression (@pxref{G-Expressions}):
24136 #~(string-append #$shadow "/bin/passwd")
24139 A default set of setuid programs is defined by the
24140 @code{%setuid-programs} variable of the @code{(gnu system)} module.
24142 @defvr {Scheme Variable} %setuid-programs
24143 A list of G-expressions denoting common programs that are setuid-root.
24145 The list includes commands such as @command{passwd}, @command{ping},
24146 @command{su}, and @command{sudo}.
24149 Under the hood, the actual setuid programs are created in the
24150 @file{/run/setuid-programs} directory at system activation time. The
24151 files in this directory refer to the ``real'' binaries, which are in the
24154 @node X.509 Certificates
24155 @section X.509 Certificates
24157 @cindex HTTPS, certificates
24158 @cindex X.509 certificates
24160 Web servers available over HTTPS (that is, HTTP over the transport-layer
24161 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
24162 that the client can then use to @emph{authenticate} the server. To do
24163 that, clients verify that the server's certificate is signed by a
24164 so-called @dfn{certificate authority} (CA). But to verify the CA's
24165 signature, clients must have first acquired the CA's certificate.
24167 Web browsers such as GNU@tie{}IceCat include their own set of CA
24168 certificates, such that they are able to verify CA signatures
24171 However, most other programs that can talk HTTPS---@command{wget},
24172 @command{git}, @command{w3m}, etc.---need to be told where CA
24173 certificates can be found.
24175 @cindex @code{nss-certs}
24176 In Guix, this is done by adding a package that provides certificates
24177 to the @code{packages} field of the @code{operating-system} declaration
24178 (@pxref{operating-system Reference}). Guix includes one such package,
24179 @code{nss-certs}, which is a set of CA certificates provided as part of
24180 Mozilla's Network Security Services.
24182 Note that it is @emph{not} part of @var{%base-packages}, so you need to
24183 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
24184 most applications and libraries look for certificates by default, points
24185 to the certificates installed globally.
24187 Unprivileged users, including users of Guix on a foreign distro,
24188 can also install their own certificate package in
24189 their profile. A number of environment variables need to be defined so
24190 that applications and libraries know where to find them. Namely, the
24191 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
24192 variables. Some applications add their own environment variables; for
24193 instance, the Git version control system honors the certificate bundle
24194 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
24195 would typically run something like:
24198 $ guix install nss-certs
24199 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
24200 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24201 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
24204 As another example, R requires the @code{CURL_CA_BUNDLE} environment
24205 variable to point to a certificate bundle, so you would have to run
24206 something like this:
24209 $ guix install nss-certs
24210 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24213 For other applications you may want to look up the required environment
24214 variable in the relevant documentation.
24217 @node Name Service Switch
24218 @section Name Service Switch
24220 @cindex name service switch
24222 The @code{(gnu system nss)} module provides bindings to the
24223 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
24224 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
24225 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
24226 extended with new ``name'' lookup methods for system databases, which
24227 includes host names, service names, user accounts, and more (@pxref{Name
24228 Service Switch, System Databases and Name Service Switch,, libc, The GNU
24229 C Library Reference Manual}).
24231 The NSS configuration specifies, for each system database, which lookup
24232 method is to be used, and how the various methods are chained
24233 together---for instance, under which circumstances NSS should try the
24234 next method in the list. The NSS configuration is given in the
24235 @code{name-service-switch} field of @code{operating-system} declarations
24236 (@pxref{operating-system Reference, @code{name-service-switch}}).
24239 @cindex .local, host name lookup
24240 As an example, the declaration below configures the NSS to use the
24241 @uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
24242 back-end}, which supports host name lookups over multicast DNS (mDNS)
24243 for host names ending in @code{.local}:
24246 (name-service-switch
24247 (hosts (list %files ;first, check /etc/hosts
24249 ;; If the above did not succeed, try
24250 ;; with 'mdns_minimal'.
24252 (name "mdns_minimal")
24254 ;; 'mdns_minimal' is authoritative for
24255 ;; '.local'. When it returns "not found",
24256 ;; no need to try the next methods.
24257 (reaction (lookup-specification
24258 (not-found => return))))
24260 ;; Then fall back to DNS.
24264 ;; Finally, try with the "full" 'mdns'.
24269 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
24270 contains this configuration, so you will not have to type it if all you
24271 want is to have @code{.local} host lookup working.
24273 Note that, in this case, in addition to setting the
24274 @code{name-service-switch} of the @code{operating-system} declaration,
24275 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
24276 @code{avahi-service-type}}), or @var{%desktop-services}, which includes it
24277 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
24278 to the name service cache daemon (@pxref{Base Services,
24279 @code{nscd-service}}).
24281 For convenience, the following variables provide typical NSS
24284 @defvr {Scheme Variable} %default-nss
24285 This is the default name service switch configuration, a
24286 @code{name-service-switch} object.
24289 @defvr {Scheme Variable} %mdns-host-lookup-nss
24290 This is the name service switch configuration with support for host name
24291 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
24294 The reference for name service switch configuration is given below. It
24295 is a direct mapping of the configuration file format of the C library , so
24296 please refer to the C library manual for more information (@pxref{NSS
24297 Configuration File,,, libc, The GNU C Library Reference Manual}).
24298 Compared to the configuration file format of libc NSS, it has the advantage
24299 not only of adding this warm parenthetic feel that we like, but also
24300 static checks: you will know about syntax errors and typos as soon as you
24301 run @command{guix system}.
24303 @deftp {Data Type} name-service-switch
24305 This is the data type representation the configuration of libc's name
24306 service switch (NSS). Each field below represents one of the supported
24323 The system databases handled by the NSS. Each of these fields must be a
24324 list of @code{<name-service>} objects (see below).
24328 @deftp {Data Type} name-service
24330 This is the data type representing an actual name service and the
24331 associated lookup action.
24335 A string denoting the name service (@pxref{Services in the NSS
24336 configuration,,, libc, The GNU C Library Reference Manual}).
24338 Note that name services listed here must be visible to nscd. This is
24339 achieved by passing the @code{#:name-services} argument to
24340 @code{nscd-service} the list of packages providing the needed name
24341 services (@pxref{Base Services, @code{nscd-service}}).
24344 An action specified using the @code{lookup-specification} macro
24345 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
24346 Reference Manual}). For example:
24349 (lookup-specification (unavailable => continue)
24350 (success => return))
24355 @node Initial RAM Disk
24356 @section Initial RAM Disk
24359 @cindex initial RAM disk
24360 For bootstrapping purposes, the Linux-Libre kernel is passed an
24361 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
24362 root file system as well as an initialization script. The latter is
24363 responsible for mounting the real root file system, and for loading any
24364 kernel modules that may be needed to achieve that.
24366 The @code{initrd-modules} field of an @code{operating-system}
24367 declaration allows you to specify Linux-libre kernel modules that must
24368 be available in the initrd. In particular, this is where you would list
24369 modules needed to actually drive the hard disk where your root partition
24370 is---although the default value of @code{initrd-modules} should cover
24371 most use cases. For example, assuming you need the @code{megaraid_sas}
24372 module in addition to the default modules to be able to access your root
24373 file system, you would write:
24378 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
24381 @defvr {Scheme Variable} %base-initrd-modules
24382 This is the list of kernel modules included in the initrd by default.
24385 Furthermore, if you need lower-level customization, the @code{initrd}
24386 field of an @code{operating-system} declaration allows
24387 you to specify which initrd you would like to use. The @code{(gnu
24388 system linux-initrd)} module provides three ways to build an initrd: the
24389 high-level @code{base-initrd} procedure and the low-level
24390 @code{raw-initrd} and @code{expression->initrd} procedures.
24392 The @code{base-initrd} procedure is intended to cover most common uses.
24393 For example, if you want to add a bunch of kernel modules to be loaded
24394 at boot time, you can define the @code{initrd} field of the operating
24395 system declaration like this:
24398 (initrd (lambda (file-systems . rest)
24399 ;; Create a standard initrd but set up networking
24400 ;; with the parameters QEMU expects by default.
24401 (apply base-initrd file-systems
24402 #:qemu-networking? #t
24406 The @code{base-initrd} procedure also handles common use cases that
24407 involves using the system as a QEMU guest, or as a ``live'' system with
24408 volatile root file system.
24410 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
24411 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
24412 such as trying to guess which kernel modules and packages should be included
24413 to the initrd. An example use of @code{raw-initrd} is when a user has
24414 a custom Linux kernel configuration and default kernel modules included by
24415 @code{base-initrd} are not available.
24417 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
24418 honors several options passed on the Linux kernel command line
24419 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
24420 @code{-append} option of QEMU), notably:
24423 @item --load=@var{boot}
24424 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
24425 program, once it has mounted the root file system.
24427 Guix uses this option to yield control to a boot program that runs the
24428 service activation programs and then spawns the GNU@tie{}Shepherd, the
24429 initialization system.
24431 @item --root=@var{root}
24432 Mount @var{root} as the root file system. @var{root} can be a
24433 device name like @code{/dev/sda1}, a file system label, or a file system
24436 @item --system=@var{system}
24437 Have @file{/run/booted-system} and @file{/run/current-system} point to
24440 @item modprobe.blacklist=@var{modules}@dots{}
24441 @cindex module, black-listing
24442 @cindex black list, of kernel modules
24443 Instruct the initial RAM disk as well as the @command{modprobe} command
24444 (from the kmod package) to refuse to load @var{modules}. @var{modules}
24445 must be a comma-separated list of module names---e.g.,
24446 @code{usbkbd,9pnet}.
24449 Start a read-eval-print loop (REPL) from the initial RAM disk before it
24450 tries to load kernel modules and to mount the root file system. Our
24451 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
24452 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
24453 Manual}, for more information on Guile's REPL.
24457 Now that you know all the features that initial RAM disks produced by
24458 @code{base-initrd} and @code{raw-initrd} provide,
24459 here is how to use it and customize it further.
24462 @cindex initial RAM disk
24463 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
24464 [#:linux-modules '()] [#:mapped-devices '()] @
24465 [#:keyboard-layout #f] @
24466 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
24467 Return a derivation that builds a raw initrd. @var{file-systems} is
24468 a list of file systems to be mounted by the initrd, possibly in addition to
24469 the root file system specified on the kernel command line via @code{--root}.
24470 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
24471 @var{mapped-devices} is a list of device mappings to realize before
24472 @var{file-systems} are mounted (@pxref{Mapped Devices}).
24473 @var{helper-packages} is a list of packages to be copied in the initrd. It may
24474 include @code{e2fsck/static} or other packages needed by the initrd to check
24475 the root file system.
24477 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24478 the desired console keyboard layout. This is done before @var{mapped-devices}
24479 are set up and before @var{file-systems} are mounted such that, should the
24480 user need to enter a passphrase or use the REPL, this happens using the
24481 intended keyboard layout.
24483 When @var{qemu-networking?} is true, set up networking with the standard QEMU
24484 parameters. When @var{virtio?} is true, load additional modules so that the
24485 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
24487 When @var{volatile-root?} is true, the root file system is writable but any changes
24491 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
24492 [#:mapped-devices '()] [#:keyboard-layout #f] @
24493 [#:qemu-networking? #f] [#:volatile-root? #f] @
24494 [#:linux-modules '()]
24495 Return as a file-like object a generic initrd, with kernel
24496 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
24497 mounted by the initrd, possibly in addition to the root file system specified
24498 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
24499 mappings to realize before @var{file-systems} are mounted.
24501 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24502 the desired console keyboard layout. This is done before @var{mapped-devices}
24503 are set up and before @var{file-systems} are mounted such that, should the
24504 user need to enter a passphrase or use the REPL, this happens using the
24505 intended keyboard layout.
24507 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
24509 The initrd is automatically populated with all the kernel modules necessary
24510 for @var{file-systems} and for the given options. Additional kernel
24511 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
24512 loaded at boot time in the order in which they appear.
24515 Needless to say, the initrds we produce and use embed a
24516 statically-linked Guile, and the initialization program is a Guile
24517 program. That gives a lot of flexibility. The
24518 @code{expression->initrd} procedure builds such an initrd, given the
24519 program to run in that initrd.
24521 @deffn {Scheme Procedure} expression->initrd @var{exp} @
24522 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
24523 Return as a file-like object a Linux initrd (a gzipped cpio archive)
24524 containing @var{guile} and that evaluates @var{exp}, a G-expression,
24525 upon booting. All the derivations referenced by @var{exp} are
24526 automatically copied to the initrd.
24529 @node Bootloader Configuration
24530 @section Bootloader Configuration
24533 @cindex boot loader
24535 The operating system supports multiple bootloaders. The bootloader is
24536 configured using @code{bootloader-configuration} declaration. All the
24537 fields of this structure are bootloader agnostic except for one field,
24538 @code{bootloader} that indicates the bootloader to be configured and
24541 Some of the bootloaders do not honor every field of
24542 @code{bootloader-configuration}. For instance, the extlinux
24543 bootloader does not support themes and thus ignores the @code{theme}
24546 @deftp {Data Type} bootloader-configuration
24547 The type of a bootloader configuration declaration.
24551 @item @code{bootloader}
24552 @cindex EFI, bootloader
24553 @cindex UEFI, bootloader
24554 @cindex BIOS, bootloader
24555 The bootloader to use, as a @code{bootloader} object. For now
24556 @code{grub-bootloader}, @code{grub-efi-bootloader},
24557 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
24559 @vindex grub-efi-bootloader
24560 @code{grub-efi-bootloader} allows to boot on modern systems using the
24561 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
24562 use if the installation image contains a @file{/sys/firmware/efi} directory
24563 when you boot it on your system.
24565 @vindex grub-bootloader
24566 @code{grub-bootloader} allows you to boot in particular Intel-based machines
24567 in ``legacy'' BIOS mode.
24569 @cindex ARM, bootloaders
24570 @cindex AArch64, bootloaders
24571 Available bootloaders are described in @code{(gnu bootloader @dots{})}
24572 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
24573 of bootloaders for a wide range of ARM and AArch64 systems, using the
24574 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
24576 @item @code{target}
24577 This is a string denoting the target onto which to install the
24580 The interpretation depends on the bootloader in question. For
24581 @code{grub-bootloader}, for example, it should be a device name understood by
24582 the bootloader @command{installer} command, such as @code{/dev/sda} or
24583 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
24584 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
24585 system, usually @file{/boot/efi}.
24587 @item @code{menu-entries} (default: @code{()})
24588 A possibly empty list of @code{menu-entry} objects (see below), denoting
24589 entries to appear in the bootloader menu, in addition to the current
24590 system entry and the entry pointing to previous system generations.
24592 @item @code{default-entry} (default: @code{0})
24593 The index of the default boot menu entry. Index 0 is for the entry of the
24596 @item @code{timeout} (default: @code{5})
24597 The number of seconds to wait for keyboard input before booting. Set to
24598 0 to boot immediately, and to -1 to wait indefinitely.
24600 @cindex keyboard layout, for the bootloader
24601 @item @code{keyboard-layout} (default: @code{#f})
24602 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
24603 layout, usually US@tie{}English (``qwerty'').
24605 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
24609 This option is currently ignored by bootloaders other than @code{grub} and
24613 @item @code{theme} (default: @var{#f})
24614 The bootloader theme object describing the theme to use. If no theme
24615 is provided, some bootloaders might use a default theme, that's true
24618 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
24619 The output terminals used for the bootloader boot menu, as a list of
24620 symbols. GRUB accepts the values: @code{console}, @code{serial},
24621 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
24622 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
24623 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
24624 configuration,,, grub,GNU GRUB manual}).
24626 @item @code{terminal-inputs} (default: @code{'()})
24627 The input terminals used for the bootloader boot menu, as a list of
24628 symbols. For GRUB, the default is the native platform terminal as
24629 determined at run-time. GRUB accepts the values: @code{console},
24630 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
24631 @code{usb_keyboard}. This field corresponds to the GRUB variable
24632 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
24635 @item @code{serial-unit} (default: @code{#f})
24636 The serial unit used by the bootloader, as an integer from 0 to 3.
24637 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
24638 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
24640 @item @code{serial-speed} (default: @code{#f})
24641 The speed of the serial interface, as an integer. For GRUB, the
24642 default value is chosen at run-time; currently GRUB chooses
24643 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
24650 Should you want to list additional boot menu entries @i{via} the
24651 @code{menu-entries} field above, you will need to create them with the
24652 @code{menu-entry} form. For example, imagine you want to be able to
24653 boot another distro (hard to imagine!), you can define a menu entry
24658 (label "The Other Distro")
24659 (linux "/boot/old/vmlinux-2.6.32")
24660 (linux-arguments '("root=/dev/sda2"))
24661 (initrd "/boot/old/initrd"))
24666 @deftp {Data Type} menu-entry
24667 The type of an entry in the bootloader menu.
24672 The label to show in the menu---e.g., @code{"GNU"}.
24675 The Linux kernel image to boot, for example:
24678 (file-append linux-libre "/bzImage")
24681 For GRUB, it is also possible to specify a device explicitly in the
24682 file path using GRUB's device naming convention (@pxref{Naming
24683 convention,,, grub, GNU GRUB manual}), for example:
24686 "(hd0,msdos1)/boot/vmlinuz"
24689 If the device is specified explicitly as above, then the @code{device}
24690 field is ignored entirely.
24692 @item @code{linux-arguments} (default: @code{()})
24693 The list of extra Linux kernel command-line arguments---e.g.,
24694 @code{("console=ttyS0")}.
24696 @item @code{initrd}
24697 A G-Expression or string denoting the file name of the initial RAM disk
24698 to use (@pxref{G-Expressions}).
24699 @item @code{device} (default: @code{#f})
24700 The device where the kernel and initrd are to be found---i.e., for GRUB,
24701 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
24703 This may be a file system label (a string), a file system UUID (a
24704 bytevector, @pxref{File Systems}), or @code{#f}, in which case
24705 the bootloader will search the device containing the file specified by
24706 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
24707 must @emph{not} be an OS device name such as @file{/dev/sda1}.
24712 @c FIXME: Write documentation once it's stable.
24713 For now only GRUB has theme support. GRUB themes are created using
24714 the @code{grub-theme} form, which is not documented yet.
24716 @defvr {Scheme Variable} %default-theme
24717 This is the default GRUB theme used by the operating system if no
24718 @code{theme} field is specified in @code{bootloader-configuration}
24721 It comes with a fancy background image displaying the GNU and Guix
24726 @node Invoking guix system
24727 @section Invoking @code{guix system}
24729 Once you have written an operating system declaration as seen in the
24730 previous section, it can be @dfn{instantiated} using the @command{guix
24731 system} command. The synopsis is:
24734 guix system @var{options}@dots{} @var{action} @var{file}
24737 @var{file} must be the name of a file containing an
24738 @code{operating-system} declaration. @var{action} specifies how the
24739 operating system is instantiated. Currently the following values are
24744 Display available service type definitions that match the given regular
24745 expressions, sorted by relevance:
24748 $ guix system search console font
24749 name: console-fonts
24750 location: gnu/services/base.scm:729:2
24751 extends: shepherd-root
24752 description: Install the given fonts on the specified ttys (fonts are
24753 + per virtual console on GNU/Linux). The value of this service is a list
24754 + of tty/font pairs like:
24756 + '(("tty1" . "LatGrkCyr-8x16"))
24760 location: gnu/services/base.scm:1048:2
24761 extends: shepherd-root
24762 description: Provide console login using the `mingetty' program.
24766 location: gnu/services/base.scm:775:2
24768 description: Provide a console log-in service as specified by its
24769 + configuration value, a `login-configuration' object.
24775 As for @command{guix package --search}, the result is written in
24776 @code{recutils} format, which makes it easy to filter the output
24777 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
24780 Build the operating system described in @var{file}, activate it, and
24781 switch to it@footnote{This action (and the related actions
24782 @code{switch-generation} and @code{roll-back}) are usable only on
24783 systems already running Guix System.}.
24785 This effects all the configuration specified in @var{file}: user
24786 accounts, system services, global package list, setuid programs, etc.
24787 The command starts system services specified in @var{file} that are not
24788 currently running; if a service is currently running this command will
24789 arrange for it to be upgraded the next time it is stopped (e.g.@: by
24790 @code{herd stop X} or @code{herd restart X}).
24792 This command creates a new generation whose number is one greater than
24793 the current generation (as reported by @command{guix system
24794 list-generations}). If that generation already exists, it will be
24795 overwritten. This behavior mirrors that of @command{guix package}
24796 (@pxref{Invoking guix package}).
24798 It also adds a bootloader menu entry for the new OS configuration,
24799 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
24800 entries for older configurations to a submenu, allowing you to choose
24801 an older system generation at boot time should you need it.
24804 @c The paragraph below refers to the problem discussed at
24805 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
24806 It is highly recommended to run @command{guix pull} once before you run
24807 @command{guix system reconfigure} for the first time (@pxref{Invoking
24808 guix pull}). Failing to do that you would see an older version of Guix
24809 once @command{reconfigure} has completed.
24812 @item switch-generation
24813 @cindex generations
24814 Switch to an existing system generation. This action atomically
24815 switches the system profile to the specified system generation. It
24816 also rearranges the system's existing bootloader menu entries. It
24817 makes the menu entry for the specified system generation the default,
24818 and it moves the entries for the other generatiors to a submenu, if
24819 supported by the bootloader being used. The next time the system
24820 boots, it will use the specified system generation.
24822 The bootloader itself is not being reinstalled when using this
24823 command. Thus, the installed bootloader is used with an updated
24824 configuration file.
24826 The target generation can be specified explicitly by its generation
24827 number. For example, the following invocation would switch to system
24831 guix system switch-generation 7
24834 The target generation can also be specified relative to the current
24835 generation with the form @code{+N} or @code{-N}, where @code{+3} means
24836 ``3 generations ahead of the current generation,'' and @code{-1} means
24837 ``1 generation prior to the current generation.'' When specifying a
24838 negative value such as @code{-1}, you must precede it with @code{--} to
24839 prevent it from being parsed as an option. For example:
24842 guix system switch-generation -- -1
24845 Currently, the effect of invoking this action is @emph{only} to switch
24846 the system profile to an existing generation and rearrange the
24847 bootloader menu entries. To actually start using the target system
24848 generation, you must reboot after running this action. In the future,
24849 it will be updated to do the same things as @command{reconfigure},
24850 like activating and deactivating services.
24852 This action will fail if the specified generation does not exist.
24855 @cindex rolling back
24856 Switch to the preceding system generation. The next time the system
24857 boots, it will use the preceding system generation. This is the inverse
24858 of @command{reconfigure}, and it is exactly the same as invoking
24859 @command{switch-generation} with an argument of @code{-1}.
24861 Currently, as with @command{switch-generation}, you must reboot after
24862 running this action to actually start using the preceding system
24865 @item delete-generations
24866 @cindex deleting system generations
24867 @cindex saving space
24868 Delete system generations, making them candidates for garbage collection
24869 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
24872 This works in the same way as @command{guix package --delete-generations}
24873 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
24874 arguments, all system generations but the current one are deleted:
24877 guix system delete-generations
24880 You can also select the generations you want to delete. The example below
24881 deletes all the system generations that are more than two month old:
24884 guix system delete-generations 2m
24887 Running this command automatically reinstalls the bootloader with an updated
24888 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
24889 longer lists the generations that have been deleted.
24892 Build the derivation of the operating system, which includes all the
24893 configuration files and programs needed to boot and run the system.
24894 This action does not actually install anything.
24897 Populate the given directory with all the files necessary to run the
24898 operating system specified in @var{file}. This is useful for first-time
24899 installations of Guix System. For instance:
24902 guix system init my-os-config.scm /mnt
24905 copies to @file{/mnt} all the store items required by the configuration
24906 specified in @file{my-os-config.scm}. This includes configuration
24907 files, packages, and so on. It also creates other essential files
24908 needed for the system to operate correctly---e.g., the @file{/etc},
24909 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
24911 This command also installs bootloader on the target specified in
24912 @file{my-os-config}, unless the @option{--no-bootloader} option was
24916 @cindex virtual machine
24918 @anchor{guix system vm}
24919 Build a virtual machine that contains the operating system declared in
24920 @var{file}, and return a script to run that virtual machine (VM).
24923 The @code{vm} action and others below
24924 can use KVM support in the Linux-libre kernel. Specifically, if the
24925 machine has hardware virtualization support, the corresponding
24926 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
24927 must exist and be readable and writable by the user and by the
24928 build users of the daemon (@pxref{Build Environment Setup}).
24931 Arguments given to the script are passed to QEMU as in the example
24932 below, which enables networking and requests 1@tie{}GiB of RAM for the
24936 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -net user
24939 The VM shares its store with the host system.
24941 Additional file systems can be shared between the host and the VM using
24942 the @code{--share} and @code{--expose} command-line options: the former
24943 specifies a directory to be shared with write access, while the latter
24944 provides read-only access to the shared directory.
24946 The example below creates a VM in which the user's home directory is
24947 accessible read-only, and where the @file{/exchange} directory is a
24948 read-write mapping of @file{$HOME/tmp} on the host:
24951 guix system vm my-config.scm \
24952 --expose=$HOME --share=$HOME/tmp=/exchange
24955 On GNU/Linux, the default is to boot directly to the kernel; this has
24956 the advantage of requiring only a very tiny root disk image since the
24957 store of the host can then be mounted.
24959 The @code{--full-boot} option forces a complete boot sequence, starting
24960 with the bootloader. This requires more disk space since a root image
24961 containing at least the kernel, initrd, and bootloader data files must
24962 be created. The @code{--image-size} option can be used to specify the
24965 @cindex System images, creation in various formats
24966 @cindex Creating system images in various formats
24969 @itemx docker-image
24970 Return a virtual machine, disk image, or Docker image of the operating
24971 system declared in @var{file} that stands alone. By default,
24972 @command{guix system} estimates the size of the image needed to store
24973 the system, but you can use the @option{--image-size} option to specify
24974 a value. Docker images are built to contain exactly what they need, so
24975 the @option{--image-size} option is ignored in the case of
24976 @code{docker-image}.
24978 You can specify the root file system type by using the
24979 @option{--file-system-type} option. It defaults to @code{ext4}.
24981 When using @code{vm-image}, the returned image is in qcow2 format, which
24982 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
24983 for more information on how to run the image in a virtual machine.
24985 When using @code{disk-image}, a raw disk image is produced; it can be
24986 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
24987 the device corresponding to a USB stick, one can copy the image to it
24988 using the following command:
24991 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
24994 When using @code{docker-image}, a Docker image is produced. Guix builds
24995 the image from scratch, not from a pre-existing Docker base image. As a
24996 result, it contains @emph{exactly} what you define in the operating
24997 system configuration file. You can then load the image and launch a
24998 Docker container using commands like the following:
25001 image_id="`docker load < guix-system-docker-image.tar.gz`"
25002 container_id="`docker create $image_id`"
25003 docker start $container_id
25006 This command starts a new Docker container from the specified image. It
25007 will boot the Guix system in the usual manner, which means it will
25008 start any services you have defined in the operating system
25009 configuration. You can get an interactive shell running in the container
25010 using @command{docker exec}:
25013 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
25016 Depending on what you run in the Docker container, it
25017 may be necessary to give the container additional permissions. For
25018 example, if you intend to build software using Guix inside of the Docker
25019 container, you may need to pass the @option{--privileged} option to
25020 @code{docker create}.
25023 Return a script to run the operating system declared in @var{file}
25024 within a container. Containers are a set of lightweight isolation
25025 mechanisms provided by the kernel Linux-libre. Containers are
25026 substantially less resource-demanding than full virtual machines since
25027 the kernel, shared objects, and other resources can be shared with the
25028 host system; this also means they provide thinner isolation.
25030 Currently, the script must be run as root in order to support more than
25031 a single user and group. The container shares its store with the host
25034 As with the @code{vm} action (@pxref{guix system vm}), additional file
25035 systems to be shared between the host and container can be specified
25036 using the @option{--share} and @option{--expose} options:
25039 guix system container my-config.scm \
25040 --expose=$HOME --share=$HOME/tmp=/exchange
25044 This option requires Linux-libre 3.19 or newer.
25049 @var{options} can contain any of the common build options (@pxref{Common
25050 Build Options}). In addition, @var{options} can contain one of the
25054 @item --expression=@var{expr}
25055 @itemx -e @var{expr}
25056 Consider the operating-system @var{expr} evaluates to.
25057 This is an alternative to specifying a file which evaluates to an
25059 This is used to generate the Guix system installer @pxref{Building the
25060 Installation Image}).
25062 @item --system=@var{system}
25063 @itemx -s @var{system}
25064 Attempt to build for @var{system} instead of the host system type.
25065 This works as per @command{guix build} (@pxref{Invoking guix build}).
25069 Return the derivation file name of the given operating system without
25072 @item --file-system-type=@var{type}
25073 @itemx -t @var{type}
25074 For the @code{disk-image} action, create a file system of the given
25075 @var{type} on the image.
25077 When this option is omitted, @command{guix system} uses @code{ext4}.
25079 @cindex ISO-9660 format
25080 @cindex CD image format
25081 @cindex DVD image format
25082 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
25083 for burning on CDs and DVDs.
25085 @item --image-size=@var{size}
25086 For the @code{vm-image} and @code{disk-image} actions, create an image
25087 of the given @var{size}. @var{size} may be a number of bytes, or it may
25088 include a unit as a suffix (@pxref{Block size, size specifications,,
25089 coreutils, GNU Coreutils}).
25091 When this option is omitted, @command{guix system} computes an estimate
25092 of the image size as a function of the size of the system declared in
25097 For the @code{container} action, allow containers to access the host network,
25098 that is, do not create a network namespace.
25100 @item --root=@var{file}
25101 @itemx -r @var{file}
25102 Make @var{file} a symlink to the result, and register it as a garbage
25105 @item --skip-checks
25106 Skip pre-installation safety checks.
25108 By default, @command{guix system init} and @command{guix system
25109 reconfigure} perform safety checks: they make sure the file systems that
25110 appear in the @code{operating-system} declaration actually exist
25111 (@pxref{File Systems}), and that any Linux kernel modules that may be
25112 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
25113 RAM Disk}). Passing this option skips these tests altogether.
25116 @cindex on-error strategy
25117 @cindex error strategy
25118 @item --on-error=@var{strategy}
25119 Apply @var{strategy} when an error occurs when reading @var{file}.
25120 @var{strategy} may be one of the following:
25123 @item nothing-special
25124 Report the error concisely and exit. This is the default strategy.
25127 Likewise, but also display a backtrace.
25130 Report the error and enter Guile's debugger. From there, you can run
25131 commands such as @code{,bt} to get a backtrace, @code{,locals} to
25132 display local variable values, and more generally inspect the state of the
25133 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
25134 a list of available debugging commands.
25138 Once you have built, configured, re-configured, and re-re-configured
25139 your Guix installation, you may find it useful to list the operating
25140 system generations available on disk---and that you can choose from the
25141 bootloader boot menu:
25145 @item list-generations
25146 List a summary of each generation of the operating system available on
25147 disk, in a human-readable way. This is similar to the
25148 @option{--list-generations} option of @command{guix package}
25149 (@pxref{Invoking guix package}).
25151 Optionally, one can specify a pattern, with the same syntax that is used
25152 in @command{guix package --list-generations}, to restrict the list of
25153 generations displayed. For instance, the following command displays
25154 generations that are up to 10 days old:
25157 $ guix system list-generations 10d
25162 The @command{guix system} command has even more to offer! The following
25163 sub-commands allow you to visualize how your system services relate to
25166 @anchor{system-extension-graph}
25169 @item extension-graph
25170 Emit in Dot/Graphviz format to standard output the @dfn{service
25171 extension graph} of the operating system defined in @var{file}
25172 (@pxref{Service Composition}, for more information on service
25178 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
25181 produces a PDF file showing the extension relations among services.
25183 @anchor{system-shepherd-graph}
25184 @item shepherd-graph
25185 Emit in Dot/Graphviz format to standard output the @dfn{dependency
25186 graph} of shepherd services of the operating system defined in
25187 @var{file}. @xref{Shepherd Services}, for more information and for an
25192 @node Running Guix in a VM
25193 @section Running Guix in a Virtual Machine
25195 @cindex virtual machine
25196 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
25198 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
25199 This image is a compressed image in QCOW format. You will first need to
25200 decompress with @command{xz -d}, and then you can pass it to an emulator such
25201 as QEMU (see below for details).
25203 This image boots the Xfce graphical environment and it contains some
25204 commonly-used tools. You can install more software in the image by running
25205 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
25206 also reconfigure the system based on its initial configuration file available
25207 as @file{/etc/config.scm} (@pxref{Using the Configuration System}).
25209 Instead of using this pre-built image, one can also build their own virtual
25210 machine image using @command{guix system vm-image} (@pxref{Invoking guix
25211 system}). The returned image is in qcow2 format, which the
25212 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
25215 If you built your own image, you must copy it out of the store
25216 (@pxref{The Store}) and give yourself permission to write to the copy
25217 before you can use it. When invoking QEMU, you must choose a system
25218 emulator that is suitable for your hardware platform. Here is a minimal
25219 QEMU invocation that will boot the result of @command{guix system
25220 vm-image} on x86_64 hardware:
25223 $ qemu-system-x86_64 \
25224 -net user -net nic,model=virtio \
25225 -enable-kvm -m 512 \
25226 -device virtio-blk,drive=myhd \
25227 -drive if=none,file=/tmp/qemu-image,id=myhd
25230 Here is what each of these options means:
25233 @item qemu-system-x86_64
25234 This specifies the hardware platform to emulate. This should match the
25238 Enable the unprivileged user-mode network stack. The guest OS can
25239 access the host but not vice versa. This is the simplest way to get the
25242 @item -net nic,model=virtio
25243 You must create a network interface of a given model. If you do not
25244 create a NIC, the boot will fail. Assuming your hardware platform is
25245 x86_64, you can get a list of available NIC models by running
25246 @command{qemu-system-x86_64 -net nic,model=help}.
25249 If your system has hardware virtualization extensions, enabling the
25250 virtual machine support (KVM) of the Linux kernel will make things run
25253 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
25255 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
25256 which may be insufficient for some operations.
25258 @item -device virtio-blk,drive=myhd
25259 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
25260 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
25261 better performance than if it were emulating a complete disk drive. See the
25262 QEMU and KVM documentation for more info.
25264 @item -drive if=none,file=/tmp/qemu-image,id=myhd
25265 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
25266 the ``myhd'' drive.
25269 The default @command{run-vm.sh} script that is returned by an invocation of
25270 @command{guix system vm} does not add a @command{-net user} flag by default.
25271 To get network access from within the vm add the @code{(dhcp-client-service)}
25272 to your system definition and start the VM using
25273 @command{`guix system vm config.scm` -net user}. An important caveat of using
25274 @command{-net user} for networking is that @command{ping} will not work, because
25275 it uses the ICMP protocol. You'll have to use a different command to check for
25276 network connectivity, for example @command{guix download}.
25278 @subsection Connecting Through SSH
25282 To enable SSH inside a VM you need to add an SSH server like
25283 @code{openssh-service-type} to your VM (@pxref{Networking Services,
25284 @code{openssh-service-type}}). In addition you need to forward the SSH port,
25285 22 by default, to the host. You can do this with
25288 `guix system vm config.scm` -net user,hostfwd=tcp::10022-:22
25291 To connect to the VM you can run
25294 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
25297 The @command{-p} tells @command{ssh} the port you want to connect to.
25298 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
25299 every time you modify your @command{config.scm} file and the
25300 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
25301 connection to an unknown host every time you connect.
25303 @subsection Using @command{virt-viewer} with Spice
25305 As an alternative to the default @command{qemu} graphical client you can
25306 use the @command{remote-viewer} from the @command{virt-viewer} package. To
25307 connect pass the @command{-spice port=5930,disable-ticketing} flag to
25308 @command{qemu}. See previous section for further information on how to do this.
25310 Spice also allows you to do some nice stuff like share your clipboard with your
25311 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
25314 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
25315 -chardev spicevmc,name=vdagent,id=vdagent
25316 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
25317 name=com.redhat.spice.0
25320 You'll also need to add the @pxref{Miscellaneous Services, Spice service}.
25322 @node Defining Services
25323 @section Defining Services
25325 The previous sections show the available services and how one can combine
25326 them in an @code{operating-system} declaration. But how do we define
25327 them in the first place? And what is a service anyway?
25330 * Service Composition:: The model for composing services.
25331 * Service Types and Services:: Types and services.
25332 * Service Reference:: API reference.
25333 * Shepherd Services:: A particular type of service.
25336 @node Service Composition
25337 @subsection Service Composition
25341 Here we define a @dfn{service} as, broadly, something that extends the
25342 functionality of the operating system. Often a service is a process---a
25343 @dfn{daemon}---started when the system boots: a secure shell server, a
25344 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
25345 whose execution can be triggered by another daemon---e.g., an FTP server
25346 started by @command{inetd} or a D-Bus service activated by
25347 @command{dbus-daemon}. Occasionally, a service does not map to a
25348 daemon. For instance, the ``account'' service collects user accounts
25349 and makes sure they exist when the system runs; the ``udev'' service
25350 collects device management rules and makes them available to the eudev
25351 daemon; the @file{/etc} service populates the @file{/etc} directory
25354 @cindex service extensions
25355 Guix system services are connected by @dfn{extensions}. For instance, the
25356 secure shell service @emph{extends} the Shepherd---the
25357 initialization system, running as PID@tie{}1---by giving it the command
25358 lines to start and stop the secure shell daemon (@pxref{Networking
25359 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
25360 service by passing it its @file{.service} specification, and extends the
25361 udev service by passing it device management rules (@pxref{Desktop
25362 Services, @code{upower-service}}); the Guix daemon service extends the
25363 Shepherd by passing it the command lines to start and stop the daemon,
25364 and extends the account service by passing it a list of required build
25365 user accounts (@pxref{Base Services}).
25367 All in all, services and their ``extends'' relations form a directed
25368 acyclic graph (DAG). If we represent services as boxes and extensions
25369 as arrows, a typical system might provide something like this:
25371 @image{images/service-graph,,5in,Typical service extension graph.}
25373 @cindex system service
25374 At the bottom, we see the @dfn{system service}, which produces the
25375 directory containing everything to run and boot the system, as returned
25376 by the @command{guix system build} command. @xref{Service Reference},
25377 to learn about the other service types shown here.
25378 @xref{system-extension-graph, the @command{guix system extension-graph}
25379 command}, for information on how to generate this representation for a
25380 particular operating system definition.
25382 @cindex service types
25383 Technically, developers can define @dfn{service types} to express these
25384 relations. There can be any number of services of a given type on the
25385 system---for instance, a system running two instances of the GNU secure
25386 shell server (lsh) has two instances of @code{lsh-service-type}, with
25387 different parameters.
25389 The following section describes the programming interface for service
25390 types and services.
25392 @node Service Types and Services
25393 @subsection Service Types and Services
25395 A @dfn{service type} is a node in the DAG described above. Let us start
25396 with a simple example, the service type for the Guix build daemon
25397 (@pxref{Invoking guix-daemon}):
25400 (define guix-service-type
25404 (list (service-extension shepherd-root-service-type guix-shepherd-service)
25405 (service-extension account-service-type guix-accounts)
25406 (service-extension activation-service-type guix-activation)))
25407 (default-value (guix-configuration))))
25411 It defines three things:
25415 A name, whose sole purpose is to make inspection and debugging easier.
25418 A list of @dfn{service extensions}, where each extension designates the
25419 target service type and a procedure that, given the parameters of the
25420 service, returns a list of objects to extend the service of that type.
25422 Every service type has at least one service extension. The only
25423 exception is the @dfn{boot service type}, which is the ultimate service.
25426 Optionally, a default value for instances of this type.
25429 In this example, @code{guix-service-type} extends three services:
25432 @item shepherd-root-service-type
25433 The @code{guix-shepherd-service} procedure defines how the Shepherd
25434 service is extended. Namely, it returns a @code{<shepherd-service>}
25435 object that defines how @command{guix-daemon} is started and stopped
25436 (@pxref{Shepherd Services}).
25438 @item account-service-type
25439 This extension for this service is computed by @code{guix-accounts},
25440 which returns a list of @code{user-group} and @code{user-account}
25441 objects representing the build user accounts (@pxref{Invoking
25444 @item activation-service-type
25445 Here @code{guix-activation} is a procedure that returns a gexp, which is
25446 a code snippet to run at ``activation time''---e.g., when the service is
25450 A service of this type is instantiated like this:
25453 (service guix-service-type
25454 (guix-configuration
25456 (use-substitutes? #f)))
25459 The second argument to the @code{service} form is a value representing
25460 the parameters of this specific service instance.
25461 @xref{guix-configuration-type, @code{guix-configuration}}, for
25462 information about the @code{guix-configuration} data type. When the
25463 value is omitted, the default value specified by
25464 @code{guix-service-type} is used:
25467 (service guix-service-type)
25470 @code{guix-service-type} is quite simple because it extends other
25471 services but is not extensible itself.
25473 @c @subsubsubsection Extensible Service Types
25475 The service type for an @emph{extensible} service looks like this:
25478 (define udev-service-type
25479 (service-type (name 'udev)
25481 (list (service-extension shepherd-root-service-type
25482 udev-shepherd-service)))
25484 (compose concatenate) ;concatenate the list of rules
25485 (extend (lambda (config rules)
25487 (($ <udev-configuration> udev initial-rules)
25488 (udev-configuration
25489 (udev udev) ;the udev package to use
25490 (rules (append initial-rules rules)))))))))
25493 This is the service type for the
25494 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
25495 management daemon}. Compared to the previous example, in addition to an
25496 extension of @code{shepherd-root-service-type}, we see two new fields:
25500 This is the procedure to @dfn{compose} the list of extensions to
25501 services of this type.
25503 Services can extend the udev service by passing it lists of rules; we
25504 compose those extensions simply by concatenating them.
25507 This procedure defines how the value of the service is @dfn{extended} with
25508 the composition of the extensions.
25510 Udev extensions are composed into a list of rules, but the udev service
25511 value is itself a @code{<udev-configuration>} record. So here, we
25512 extend that record by appending the list of rules it contains to the
25513 list of contributed rules.
25516 This is a string giving an overview of the service type. The string can
25517 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
25518 @command{guix system search} command searches these strings and displays
25519 them (@pxref{Invoking guix system}).
25522 There can be only one instance of an extensible service type such as
25523 @code{udev-service-type}. If there were more, the
25524 @code{service-extension} specifications would be ambiguous.
25526 Still here? The next section provides a reference of the programming
25527 interface for services.
25529 @node Service Reference
25530 @subsection Service Reference
25532 We have seen an overview of service types (@pxref{Service Types and
25533 Services}). This section provides a reference on how to manipulate
25534 services and service types. This interface is provided by the
25535 @code{(gnu services)} module.
25537 @deffn {Scheme Procedure} service @var{type} [@var{value}]
25538 Return a new service of @var{type}, a @code{<service-type>} object (see
25539 below.) @var{value} can be any object; it represents the parameters of
25540 this particular service instance.
25542 When @var{value} is omitted, the default value specified by @var{type}
25543 is used; if @var{type} does not specify a default value, an error is
25546 For instance, this:
25549 (service openssh-service-type)
25553 is equivalent to this:
25556 (service openssh-service-type
25557 (openssh-configuration))
25560 In both cases the result is an instance of @code{openssh-service-type}
25561 with the default configuration.
25564 @deffn {Scheme Procedure} service? @var{obj}
25565 Return true if @var{obj} is a service.
25568 @deffn {Scheme Procedure} service-kind @var{service}
25569 Return the type of @var{service}---i.e., a @code{<service-type>} object.
25572 @deffn {Scheme Procedure} service-value @var{service}
25573 Return the value associated with @var{service}. It represents its
25577 Here is an example of how a service is created and manipulated:
25581 (service nginx-service-type
25582 (nginx-configuration
25584 (log-directory log-directory)
25585 (run-directory run-directory)
25586 (file config-file))))
25591 (eq? (service-kind s) nginx-service-type)
25595 The @code{modify-services} form provides a handy way to change the
25596 parameters of some of the services of a list such as
25597 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
25598 evaluates to a list of services. Of course, you could always use
25599 standard list combinators such as @code{map} and @code{fold} to do that
25600 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
25601 @code{modify-services} simply provides a more concise form for this
25604 @deffn {Scheme Syntax} modify-services @var{services} @
25605 (@var{type} @var{variable} => @var{body}) @dots{}
25607 Modify the services listed in @var{services} according to the given
25608 clauses. Each clause has the form:
25611 (@var{type} @var{variable} => @var{body})
25614 where @var{type} is a service type---e.g.,
25615 @code{guix-service-type}---and @var{variable} is an identifier that is
25616 bound within the @var{body} to the service parameters---e.g., a
25617 @code{guix-configuration} instance---of the original service of that
25620 The @var{body} should evaluate to the new service parameters, which will
25621 be used to configure the new service. This new service will replace the
25622 original in the resulting list. Because a service's service parameters
25623 are created using @code{define-record-type*}, you can write a succinct
25624 @var{body} that evaluates to the new service parameters by using the
25625 @code{inherit} feature that @code{define-record-type*} provides.
25627 @xref{Using the Configuration System}, for example usage.
25631 Next comes the programming interface for service types. This is
25632 something you want to know when writing new service definitions, but not
25633 necessarily when simply looking for ways to customize your
25634 @code{operating-system} declaration.
25636 @deftp {Data Type} service-type
25637 @cindex service type
25638 This is the representation of a @dfn{service type} (@pxref{Service Types
25643 This is a symbol, used only to simplify inspection and debugging.
25645 @item @code{extensions}
25646 A non-empty list of @code{<service-extension>} objects (see below).
25648 @item @code{compose} (default: @code{#f})
25649 If this is @code{#f}, then the service type denotes services that cannot
25650 be extended---i.e., services that do not receive ``values'' from other
25653 Otherwise, it must be a one-argument procedure. The procedure is called
25654 by @code{fold-services} and is passed a list of values collected from
25655 extensions. It may return any single value.
25657 @item @code{extend} (default: @code{#f})
25658 If this is @code{#f}, services of this type cannot be extended.
25660 Otherwise, it must be a two-argument procedure: @code{fold-services}
25661 calls it, passing it the initial value of the service as the first
25662 argument and the result of applying @code{compose} to the extension
25663 values as the second argument. It must return a value that is a valid
25664 parameter value for the service instance.
25667 @xref{Service Types and Services}, for examples.
25670 @deffn {Scheme Procedure} service-extension @var{target-type} @
25672 Return a new extension for services of type @var{target-type}.
25673 @var{compute} must be a one-argument procedure: @code{fold-services}
25674 calls it, passing it the value associated with the service that provides
25675 the extension; it must return a valid value for the target service.
25678 @deffn {Scheme Procedure} service-extension? @var{obj}
25679 Return true if @var{obj} is a service extension.
25682 Occasionally, you might want to simply extend an existing service. This
25683 involves creating a new service type and specifying the extension of
25684 interest, which can be verbose; the @code{simple-service} procedure
25685 provides a shorthand for this.
25687 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
25688 Return a service that extends @var{target} with @var{value}. This works
25689 by creating a singleton service type @var{name}, of which the returned
25690 service is an instance.
25692 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
25696 (simple-service 'my-mcron-job mcron-service-type
25697 #~(job '(next-hour (3)) "guix gc -F 2G"))
25701 At the core of the service abstraction lies the @code{fold-services}
25702 procedure, which is responsible for ``compiling'' a list of services
25703 down to a single directory that contains everything needed to boot and
25704 run the system---the directory shown by the @command{guix system build}
25705 command (@pxref{Invoking guix system}). In essence, it propagates
25706 service extensions down the service graph, updating each node parameters
25707 on the way, until it reaches the root node.
25709 @deffn {Scheme Procedure} fold-services @var{services} @
25710 [#:target-type @var{system-service-type}]
25711 Fold @var{services} by propagating their extensions down to the root of
25712 type @var{target-type}; return the root service adjusted accordingly.
25715 Lastly, the @code{(gnu services)} module also defines several essential
25716 service types, some of which are listed below.
25718 @defvr {Scheme Variable} system-service-type
25719 This is the root of the service graph. It produces the system directory
25720 as returned by the @command{guix system build} command.
25723 @defvr {Scheme Variable} boot-service-type
25724 The type of the ``boot service'', which produces the @dfn{boot script}.
25725 The boot script is what the initial RAM disk runs when booting.
25728 @defvr {Scheme Variable} etc-service-type
25729 The type of the @file{/etc} service. This service is used to create
25730 files under @file{/etc} and can be extended by
25731 passing it name/file tuples such as:
25734 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
25737 In this example, the effect would be to add an @file{/etc/issue} file
25738 pointing to the given file.
25741 @defvr {Scheme Variable} setuid-program-service-type
25742 Type for the ``setuid-program service''. This service collects lists of
25743 executable file names, passed as gexps, and adds them to the set of
25744 setuid-root programs on the system (@pxref{Setuid Programs}).
25747 @defvr {Scheme Variable} profile-service-type
25748 Type of the service that populates the @dfn{system profile}---i.e., the
25749 programs under @file{/run/current-system/profile}. Other services can
25750 extend it by passing it lists of packages to add to the system profile.
25754 @node Shepherd Services
25755 @subsection Shepherd Services
25757 @cindex shepherd services
25759 @cindex init system
25760 The @code{(gnu services shepherd)} module provides a way to define
25761 services managed by the GNU@tie{}Shepherd, which is the
25762 initialization system---the first process that is started when the
25763 system boots, also known as PID@tie{}1
25764 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
25766 Services in the Shepherd can depend on each other. For instance, the
25767 SSH daemon may need to be started after the syslog daemon has been
25768 started, which in turn can only happen once all the file systems have
25769 been mounted. The simple operating system defined earlier (@pxref{Using
25770 the Configuration System}) results in a service graph like this:
25772 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
25774 You can actually generate such a graph for any operating system
25775 definition using the @command{guix system shepherd-graph} command
25776 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
25778 The @code{%shepherd-root-service} is a service object representing
25779 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
25780 by passing it lists of @code{<shepherd-service>} objects.
25782 @deftp {Data Type} shepherd-service
25783 The data type representing a service managed by the Shepherd.
25786 @item @code{provision}
25787 This is a list of symbols denoting what the service provides.
25789 These are the names that may be passed to @command{herd start},
25790 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
25791 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
25792 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
25794 @item @code{requirement} (default: @code{'()})
25795 List of symbols denoting the Shepherd services this one depends on.
25797 @cindex one-shot services, for the Shepherd
25798 @item @code{one-shot?} (default: @code{#f})
25799 Whether this service is @dfn{one-shot}. One-shot services stop immediately
25800 after their @code{start} action has completed. @xref{Slots of services,,,
25801 shepherd, The GNU Shepherd Manual}, for more info.
25803 @item @code{respawn?} (default: @code{#t})
25804 Whether to restart the service when it stops, for instance when the
25805 underlying process dies.
25808 @itemx @code{stop} (default: @code{#~(const #f)})
25809 The @code{start} and @code{stop} fields refer to the Shepherd's
25810 facilities to start and stop processes (@pxref{Service De- and
25811 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
25812 G-expressions that get expanded in the Shepherd configuration file
25813 (@pxref{G-Expressions}).
25815 @item @code{actions} (default: @code{'()})
25816 @cindex actions, of Shepherd services
25817 This is a list of @code{shepherd-action} objects (see below) defining
25818 @dfn{actions} supported by the service, in addition to the standard
25819 @code{start} and @code{stop} actions. Actions listed here become available as
25820 @command{herd} sub-commands:
25823 herd @var{action} @var{service} [@var{arguments}@dots{}]
25826 @item @code{auto-start?} (default: @code{#t})
25827 Whether this service should be started automatically by the Shepherd. If it
25828 is @code{#f} the service has to be started manually with @code{herd start}.
25830 @item @code{documentation}
25831 A documentation string, as shown when running:
25834 herd doc @var{service-name}
25837 where @var{service-name} is one of the symbols in @code{provision}
25838 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
25840 @item @code{modules} (default: @code{%default-modules})
25841 This is the list of modules that must be in scope when @code{start} and
25842 @code{stop} are evaluated.
25847 @deftp {Data Type} shepherd-action
25848 This is the data type that defines additional actions implemented by a
25849 Shepherd service (see above).
25853 Symbol naming the action.
25855 @item documentation
25856 This is a documentation string for the action. It can be viewed by running:
25859 herd doc @var{service} action @var{action}
25863 This should be a gexp that evaluates to a procedure of at least one argument,
25864 which is the ``running value'' of the service (@pxref{Slots of services,,,
25865 shepherd, The GNU Shepherd Manual}).
25868 The following example defines an action called @code{say-hello} that kindly
25874 (documentation "Say hi!")
25875 (procedure #~(lambda (running . args)
25876 (format #t "Hello, friend! arguments: ~s\n"
25881 Assuming this action is added to the @code{example} service, then you can do:
25884 # herd say-hello example
25885 Hello, friend! arguments: ()
25886 # herd say-hello example a b c
25887 Hello, friend! arguments: ("a" "b" "c")
25890 This, as you can see, is a fairly sophisticated way to say hello.
25891 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
25895 @defvr {Scheme Variable} shepherd-root-service-type
25896 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
25898 This is the service type that extensions target when they want to create
25899 shepherd services (@pxref{Service Types and Services}, for an example).
25900 Each extension must pass a list of @code{<shepherd-service>}.
25903 @defvr {Scheme Variable} %shepherd-root-service
25904 This service represents PID@tie{}1.
25908 @node Documentation
25909 @chapter Documentation
25911 @cindex documentation, searching for
25912 @cindex searching for documentation
25913 @cindex Info, documentation format
25915 @cindex manual pages
25916 In most cases packages installed with Guix come with documentation.
25917 There are two main documentation formats: ``Info'', a browseable
25918 hypertext format used for GNU software, and ``manual pages'' (or ``man
25919 pages''), the linear documentation format traditionally found on Unix.
25920 Info manuals are accessed with the @command{info} command or with Emacs,
25921 and man pages are accessed using @command{man}.
25923 You can look for documentation of software installed on your system by
25924 keyword. For example, the following command searches for information
25925 about ``TLS'' in Info manuals:
25929 "(emacs)Network Security" -- STARTTLS
25930 "(emacs)Network Security" -- TLS
25931 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
25932 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
25937 The command below searches for the same keyword in man pages:
25941 SSL (7) - OpenSSL SSL/TLS library
25942 certtool (1) - GnuTLS certificate tool
25946 These searches are purely local to your computer so you have the
25947 guarantee that documentation you find corresponds to what you have
25948 actually installed, you can access it off-line, and your privacy is
25951 Once you have these results, you can view the relevant documentation by
25955 $ info "(gnutls)Core TLS API"
25965 Info manuals contain sections and indices as well as hyperlinks like
25966 those found in Web pages. The @command{info} reader (@pxref{Top, Info
25967 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
25968 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
25969 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
25970 Introduction}, for an introduction to Info navigation.
25972 @node Installing Debugging Files
25973 @chapter Installing Debugging Files
25975 @cindex debugging files
25976 Program binaries, as produced by the GCC compilers for instance, are
25977 typically written in the ELF format, with a section containing
25978 @dfn{debugging information}. Debugging information is what allows the
25979 debugger, GDB, to map binary code to source code; it is required to
25980 debug a compiled program in good conditions.
25982 The problem with debugging information is that is takes up a fair amount
25983 of disk space. For example, debugging information for the GNU C Library
25984 weighs in at more than 60 MiB. Thus, as a user, keeping all the
25985 debugging info of all the installed programs is usually not an option.
25986 Yet, space savings should not come at the cost of an impediment to
25987 debugging---especially in the GNU system, which should make it easier
25988 for users to exert their computing freedom (@pxref{GNU Distribution}).
25990 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
25991 mechanism that allows users to get the best of both worlds: debugging
25992 information can be stripped from the binaries and stored in separate
25993 files. GDB is then able to load debugging information from those files,
25994 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
25997 The GNU distribution takes advantage of this by storing debugging
25998 information in the @code{lib/debug} sub-directory of a separate package
25999 output unimaginatively called @code{debug} (@pxref{Packages with
26000 Multiple Outputs}). Users can choose to install the @code{debug} output
26001 of a package when they need it. For instance, the following command
26002 installs the debugging information for the GNU C Library and for GNU
26006 guix install glibc:debug guile:debug
26009 GDB must then be told to look for debug files in the user's profile, by
26010 setting the @code{debug-file-directory} variable (consider setting it
26011 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
26015 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
26018 From there on, GDB will pick up debugging information from the
26019 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
26021 In addition, you will most likely want GDB to be able to show the source
26022 code being debugged. To do that, you will have to unpack the source
26023 code of the package of interest (obtained with @code{guix build
26024 --source}, @pxref{Invoking guix build}), and to point GDB to that source
26025 directory using the @code{directory} command (@pxref{Source Path,
26026 @code{directory},, gdb, Debugging with GDB}).
26028 @c XXX: keep me up-to-date
26029 The @code{debug} output mechanism in Guix is implemented by the
26030 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
26031 opt-in---debugging information is available only for the packages
26032 with definitions explicitly declaring a @code{debug} output. This may be
26033 changed to opt-out in the future if our build farm servers can handle
26034 the load. To check whether a package has a @code{debug} output, use
26035 @command{guix package --list-available} (@pxref{Invoking guix package}).
26038 @node Security Updates
26039 @chapter Security Updates
26041 @cindex security updates
26042 @cindex security vulnerabilities
26043 Occasionally, important security vulnerabilities are discovered in software
26044 packages and must be patched. Guix developers try hard to keep track of
26045 known vulnerabilities and to apply fixes as soon as possible in the
26046 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
26047 containing only security updates.) The @command{guix lint} tool helps
26048 developers find out about vulnerable versions of software packages in the
26053 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
26054 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
26055 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
26059 @xref{Invoking guix lint}, for more information.
26062 As of version @value{VERSION}, the feature described below is considered
26066 Guix follows a functional
26067 package management discipline (@pxref{Introduction}), which implies
26068 that, when a package is changed, @emph{every package that depends on it}
26069 must be rebuilt. This can significantly slow down the deployment of
26070 fixes in core packages such as libc or Bash, since basically the whole
26071 distribution would need to be rebuilt. Using pre-built binaries helps
26072 (@pxref{Substitutes}), but deployment may still take more time than
26076 To address this, Guix implements @dfn{grafts}, a mechanism that allows
26077 for fast deployment of critical updates without the costs associated
26078 with a whole-distribution rebuild. The idea is to rebuild only the
26079 package that needs to be patched, and then to ``graft'' it onto packages
26080 explicitly installed by the user and that were previously referring to
26081 the original package. The cost of grafting is typically very low, and
26082 order of magnitudes lower than a full rebuild of the dependency chain.
26084 @cindex replacements of packages, for grafts
26085 For instance, suppose a security update needs to be applied to Bash.
26086 Guix developers will provide a package definition for the ``fixed''
26087 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
26088 Packages}). Then, the original package definition is augmented with a
26089 @code{replacement} field pointing to the package containing the bug fix:
26096 (replacement bash-fixed)))
26099 From there on, any package depending directly or indirectly on Bash---as
26100 reported by @command{guix gc --requisites} (@pxref{Invoking guix
26101 gc})---that is installed is automatically ``rewritten'' to refer to
26102 @code{bash-fixed} instead of @code{bash}. This grafting process takes
26103 time proportional to the size of the package, usually less than a
26104 minute for an ``average'' package on a recent machine. Grafting is
26105 recursive: when an indirect dependency requires grafting, then grafting
26106 ``propagates'' up to the package that the user is installing.
26108 Currently, the length of the name and version of the graft and that of
26109 the package it replaces (@code{bash-fixed} and @code{bash} in the example
26110 above) must be equal. This restriction mostly comes from the fact that
26111 grafting works by patching files, including binary files, directly.
26112 Other restrictions may apply: for instance, when adding a graft to a
26113 package providing a shared library, the original shared library and its
26114 replacement must have the same @code{SONAME} and be binary-compatible.
26116 The @option{--no-grafts} command-line option allows you to forcefully
26117 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
26121 guix build bash --no-grafts
26125 returns the store file name of the original Bash, whereas:
26132 returns the store file name of the ``fixed'', replacement Bash. This
26133 allows you to distinguish between the two variants of Bash.
26135 To verify which Bash your whole profile refers to, you can run
26136 (@pxref{Invoking guix gc}):
26139 guix gc -R `readlink -f ~/.guix-profile` | grep bash
26143 @dots{} and compare the store file names that you get with those above.
26144 Likewise for a complete Guix system generation:
26147 guix gc -R `guix system build my-config.scm` | grep bash
26150 Lastly, to check which Bash running processes are using, you can use the
26151 @command{lsof} command:
26154 lsof | grep /gnu/store/.*bash
26158 @node Bootstrapping
26159 @chapter Bootstrapping
26161 @c Adapted from the ELS 2013 paper.
26163 @cindex bootstrapping
26165 Bootstrapping in our context refers to how the distribution gets built
26166 ``from nothing''. Remember that the build environment of a derivation
26167 contains nothing but its declared inputs (@pxref{Introduction}). So
26168 there's an obvious chicken-and-egg problem: how does the first package
26169 get built? How does the first compiler get compiled? Note that this is
26170 a question of interest only to the curious hacker, not to the regular
26171 user, so you can shamelessly skip this section if you consider yourself
26172 a ``regular user''.
26174 @cindex bootstrap binaries
26175 The GNU system is primarily made of C code, with libc at its core. The
26176 GNU build system itself assumes the availability of a Bourne shell and
26177 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
26178 `grep'. Furthermore, build programs---programs that run
26179 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
26180 (@pxref{Derivations}). Consequently, to be able to build anything at
26181 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
26182 Binutils, libc, and the other packages mentioned above---the
26183 @dfn{bootstrap binaries}.
26185 These bootstrap binaries are ``taken for granted'', though we can also
26186 re-create them if needed (more on that later).
26188 @unnumberedsec Preparing to Use the Bootstrap Binaries
26190 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
26191 @c large image, it's hard to scroll. Oh well.
26192 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
26194 The figure above shows the very beginning of the dependency graph of the
26195 distribution, corresponding to the package definitions of the @code{(gnu
26196 packages bootstrap)} module. A similar figure can be generated with
26197 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
26200 guix graph -t derivation \
26201 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
26205 At this level of detail, things are
26206 slightly complex. First, Guile itself consists of an ELF executable,
26207 along with many source and compiled Scheme files that are dynamically
26208 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
26209 tarball shown in this graph. This tarball is part of Guix's ``source''
26210 distribution, and gets inserted into the store with @code{add-to-store}
26211 (@pxref{The Store}).
26213 But how do we write a derivation that unpacks this tarball and adds it
26214 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
26215 derivation---the first one that gets built---uses @code{bash} as its
26216 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
26217 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
26218 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
26219 the Guix source distribution, whose sole purpose is to allow the Guile
26220 tarball to be unpacked.
26222 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
26223 Guile that can be used to run subsequent build programs. Its first task
26224 is to download tarballs containing the other pre-built binaries---this
26225 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
26226 @code{ftp-client.scm} are used for this purpose. The
26227 @code{module-import.drv} derivations import those modules in a directory
26228 in the store, using the original layout. The
26229 @code{module-import-compiled.drv} derivations compile those modules, and
26230 write them in an output directory with the right layout. This
26231 corresponds to the @code{#:modules} argument of
26232 @code{build-expression->derivation} (@pxref{Derivations}).
26234 Finally, the various tarballs are unpacked by the
26235 derivations @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv},
26236 etc., at which point we have a working C tool chain.
26239 @unnumberedsec Building the Build Tools
26241 Bootstrapping is complete when we have a full tool chain that does not
26242 depend on the pre-built bootstrap tools discussed above. This
26243 no-dependency requirement is verified by checking whether the files of
26244 the final tool chain contain references to the @file{/gnu/store}
26245 directories of the bootstrap inputs. The process that leads to this
26246 ``final'' tool chain is described by the package definitions found in
26247 the @code{(gnu packages commencement)} module.
26249 The @command{guix graph} command allows us to ``zoom out'' compared to
26250 the graph above, by looking at the level of package objects instead of
26251 individual derivations---remember that a package may translate to
26252 several derivations, typically one derivation to download its source,
26253 one to build the Guile modules it needs, and one to actually build the
26254 package from source. The command:
26257 guix graph -t bag \
26258 -e '(@@@@ (gnu packages commencement)
26259 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
26263 produces the dependency graph leading to the ``final'' C
26264 library@footnote{You may notice the @code{glibc-intermediate} label,
26265 suggesting that it is not @emph{quite} final, but as a good
26266 approximation, we will consider it final.}, depicted below.
26268 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
26270 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
26271 The first tool that gets built with the bootstrap binaries is
26272 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
26273 for all the following packages. From there Findutils and Diffutils get
26276 Then come the first-stage Binutils and GCC, built as pseudo cross
26277 tools---i.e., with @code{--target} equal to @code{--host}. They are
26278 used to build libc. Thanks to this cross-build trick, this libc is
26279 guaranteed not to hold any reference to the initial tool chain.
26281 From there the final Binutils and GCC (not shown above) are built.
26283 from the final Binutils, and links programs against the just-built libc.
26284 This tool chain is used to build the other packages used by Guix and by
26285 the GNU Build System: Guile, Bash, Coreutils, etc.
26287 And voilà! At this point we have the complete set of build tools that
26288 the GNU Build System expects. These are in the @code{%final-inputs}
26289 variable of the @code{(gnu packages commencement)} module, and are
26290 implicitly used by any package that uses @code{gnu-build-system}
26291 (@pxref{Build Systems, @code{gnu-build-system}}).
26294 @unnumberedsec Building the Bootstrap Binaries
26296 @cindex bootstrap binaries
26297 Because the final tool chain does not depend on the bootstrap binaries,
26298 those rarely need to be updated. Nevertheless, it is useful to have an
26299 automated way to produce them, should an update occur, and this is what
26300 the @code{(gnu packages make-bootstrap)} module provides.
26302 The following command builds the tarballs containing the bootstrap
26303 binaries (Guile, Binutils, GCC, libc, and a tarball containing a mixture
26304 of Coreutils and other basic command-line tools):
26307 guix build bootstrap-tarballs
26310 The generated tarballs are those that should be referred to in the
26311 @code{(gnu packages bootstrap)} module mentioned at the beginning of
26314 Still here? Then perhaps by now you've started to wonder: when do we
26315 reach a fixed point? That is an interesting question! The answer is
26316 unknown, but if you would like to investigate further (and have
26317 significant computational and storage resources to do so), then let us
26320 @unnumberedsec Reducing the Set of Bootstrap Binaries
26322 Our bootstrap binaries currently include GCC, Guile, etc. That's a lot
26323 of binary code! Why is that a problem? It's a problem because these
26324 big chunks of binary code are practically non-auditable, which makes it
26325 hard to establish what source code produced them. Every unauditable
26326 binary also leaves us vulnerable to compiler backdoors as described by
26327 Ken Thompson in the 1984 paper @emph{Reflections on Trusting Trust}.
26329 This is mitigated by the fact that our bootstrap binaries were generated
26330 from an earlier Guix revision. Nevertheless it lacks the level of
26331 transparency that we get in the rest of the package dependency graph,
26332 where Guix always gives us a source-to-binary mapping. Thus, our goal
26333 is to reduce the set of bootstrap binaries to the bare minimum.
26335 The @uref{http://bootstrappable.org, Bootstrappable.org web site} lists
26336 on-going projects to do that. One of these is about replacing the
26337 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
26338 of increasing complexity, which could be built from source starting from
26339 a simple and auditable assembler. Your help is welcome!
26343 @chapter Porting to a New Platform
26345 As discussed above, the GNU distribution is self-contained, and
26346 self-containment is achieved by relying on pre-built ``bootstrap
26347 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
26348 operating system kernel, CPU architecture, and application binary
26349 interface (ABI). Thus, to port the distribution to a platform that is
26350 not yet supported, one must build those bootstrap binaries, and update
26351 the @code{(gnu packages bootstrap)} module to use them on that platform.
26353 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
26354 When everything goes well, and assuming the GNU tool chain supports the
26355 target platform, this can be as simple as running a command like this
26359 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
26362 For this to work, the @code{glibc-dynamic-linker} procedure in
26363 @code{(gnu packages bootstrap)} must be augmented to return the right
26364 file name for libc's dynamic linker on that platform; likewise,
26365 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
26366 taught about the new platform.
26368 Once these are built, the @code{(gnu packages bootstrap)} module needs
26369 to be updated to refer to these binaries on the target platform. That
26370 is, the hashes and URLs of the bootstrap tarballs for the new platform
26371 must be added alongside those of the currently supported platforms. The
26372 bootstrap Guile tarball is treated specially: it is expected to be
26373 available locally, and @file{gnu/local.mk} has rules to download it for
26374 the supported architectures; a rule for the new platform must be added
26377 In practice, there may be some complications. First, it may be that the
26378 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
26379 above) is not recognized by all the GNU tools. Typically, glibc
26380 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
26381 configure flag (see @code{gcc.scm} for examples of how to handle this).
26382 Second, some of the required packages could fail to build for that
26383 platform. Lastly, the generated binaries could be broken for some
26386 @c *********************************************************************
26387 @include contributing.texi
26389 @c *********************************************************************
26390 @node Acknowledgments
26391 @chapter Acknowledgments
26393 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
26394 which was designed and
26395 implemented by Eelco Dolstra, with contributions from other people (see
26396 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
26397 management, and promoted unprecedented features, such as transactional
26398 package upgrades and rollbacks, per-user profiles, and referentially
26399 transparent build processes. Without this work, Guix would not exist.
26401 The Nix-based software distributions, Nixpkgs and NixOS, have also been
26402 an inspiration for Guix.
26404 GNU@tie{}Guix itself is a collective work with contributions from a
26405 number of people. See the @file{AUTHORS} file in Guix for more
26406 information on these fine people. The @file{THANKS} file lists people
26407 who have helped by reporting bugs, taking care of the infrastructure,
26408 providing artwork and themes, making suggestions, and more---thank you!
26411 @c *********************************************************************
26412 @node GNU Free Documentation License
26413 @appendix GNU Free Documentation License
26414 @cindex license, GNU Free Documentation License
26415 @include fdl-1.3.texi
26417 @c *********************************************************************
26418 @node Concept Index
26419 @unnumbered Concept Index
26422 @node Programming Index
26423 @unnumbered Programming Index
26424 @syncodeindex tp fn
26425 @syncodeindex vr fn
26430 @c Local Variables:
26431 @c ispell-local-dictionary: "american";