6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
14 @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=15145
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER ci.guix.gnu.org
21 @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
24 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès@*
25 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
26 Copyright @copyright{} 2013 Nikita Karetnikov@*
27 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
28 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
29 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
30 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
31 Copyright @copyright{} 2015, 2016, 2017, 2019, 2020 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018, 2019 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017 Christopher Allan Webber@*
49 Copyright @copyright{} 2017, 2018, 2019, 2020 Marius Bakke@*
50 Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
51 Copyright @copyright{} 2017, 2019, 2020 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018, 2019, 2020 Tobias Geerinckx-Rice@*
53 Copyright @copyright{} 2017 George Clemmer@*
54 Copyright @copyright{} 2017 Andy Wingo@*
55 Copyright @copyright{} 2017, 2018, 2019 Arun Isaac@*
56 Copyright @copyright{} 2017 nee@*
57 Copyright @copyright{} 2018 Rutger Helling@*
58 Copyright @copyright{} 2018 Oleg Pykhalov@*
59 Copyright @copyright{} 2018 Mike Gerwitz@*
60 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
61 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
62 Copyright @copyright{} 2018, 2019 Florian Pelz@*
63 Copyright @copyright{} 2018 Laura Lazzati@*
64 Copyright @copyright{} 2018 Alex Vong@*
65 Copyright @copyright{} 2019 Josh Holland@*
66 Copyright @copyright{} 2019, 2020 Diego Nicola Barbato@*
67 Copyright @copyright{} 2019 Ivan Petkov@*
68 Copyright @copyright{} 2019 Jakob L. Kreuze@*
69 Copyright @copyright{} 2019 Kyle Andrews@*
70 Copyright @copyright{} 2019 Alex Griffin@*
71 Copyright @copyright{} 2019 Guillaume Le Vaillant@*
72 Copyright @copyright{} 2020 Leo Prikler@*
73 Copyright @copyright{} 2019, 2020 Simon Tournier@*
74 Copyright @copyright{} 2020 Wiktor Żelazny@*
75 Copyright @copyright{} 2020 Damien Cassou@*
76 Copyright @copyright{} 2020 Jakub Kądziołka@*
77 Copyright @copyright{} 2020 Jack Hill@*
78 Copyright @copyright{} 2020 Naga Malleswari@*
79 Copyright @copyright{} 2020 Brice Waegeneire@*
80 Copyright @copyright{} 2020 R Veera Kumar@*
81 Copyright @copyright{} 2020 Pierre Langlois@*
82 Copyright @copyright{} 2020 pinoaffe@*
84 Permission is granted to copy, distribute and/or modify this document
85 under the terms of the GNU Free Documentation License, Version 1.3 or
86 any later version published by the Free Software Foundation; with no
87 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
88 copy of the license is included in the section entitled ``GNU Free
89 Documentation License''.
92 @dircategory System administration
94 * Guix: (guix). Manage installed software and system configuration.
95 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
96 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
97 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
98 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
99 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
102 @dircategory Software development
104 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
105 * guix build: (guix)Invoking guix build. Building packages.
106 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
110 @title GNU Guix Reference Manual
111 @subtitle Using the GNU Guix Functional Package Manager
112 @author The GNU Guix Developers
115 @vskip 0pt plus 1filll
116 Edition @value{EDITION} @*
124 @c *********************************************************************
128 This document describes GNU Guix version @value{VERSION}, a functional
129 package management tool written for the GNU system.
131 @c TRANSLATORS: You can replace the following paragraph with information on
132 @c how to join your own translation team and how to report issues with the
134 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
135 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
136 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
137 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
138 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
139 would like to translate it in your native language, consider joining the
140 @uref{https://translationproject.org/domain/guix-manual.html, Translation
144 * Introduction:: What is Guix about?
145 * Installation:: Installing Guix.
146 * System Installation:: Installing the whole operating system.
147 * Package Management:: Package installation, upgrade, etc.
148 * Development:: Guix-aided software development.
149 * Programming Interface:: Using Guix in Scheme.
150 * Utilities:: Package management commands.
151 * System Configuration:: Configuring the operating system.
152 * Documentation:: Browsing software user manuals.
153 * Installing Debugging Files:: Feeding the debugger.
154 * Security Updates:: Deploying security fixes quickly.
155 * Bootstrapping:: GNU/Linux built from scratch.
156 * Porting:: Targeting another platform or kernel.
157 * Contributing:: Your help needed!
159 * Acknowledgments:: Thanks!
160 * GNU Free Documentation License:: The license of this manual.
161 * Concept Index:: Concepts.
162 * Programming Index:: Data types, functions, and variables.
165 --- The Detailed Node Listing ---
169 * Managing Software the Guix Way:: What's special.
170 * GNU Distribution:: The packages and tools.
174 * Binary Installation:: Getting Guix running in no time!
175 * Requirements:: Software needed to build and run Guix.
176 * Running the Test Suite:: Testing Guix.
177 * Setting Up the Daemon:: Preparing the build daemon's environment.
178 * Invoking guix-daemon:: Running the build daemon.
179 * Application Setup:: Application-specific setup.
181 Setting Up the Daemon
183 * Build Environment Setup:: Preparing the isolated build environment.
184 * Daemon Offload Setup:: Offloading builds to remote machines.
185 * SELinux Support:: Using an SELinux policy for the daemon.
189 * Limitations:: What you can expect.
190 * Hardware Considerations:: Supported hardware.
191 * USB Stick and DVD Installation:: Preparing the installation medium.
192 * Preparing for Installation:: Networking, partitioning, etc.
193 * Guided Graphical Installation:: Easy graphical installation.
194 * Manual Installation:: Manual installation for wizards.
195 * After System Installation:: When installation succeeded.
196 * Installing Guix in a VM:: Guix System playground.
197 * Building the Installation Image:: How this comes to be.
201 * Keyboard Layout and Networking and Partitioning:: Initial setup.
202 * Proceeding with the Installation:: Installing.
206 * Features:: How Guix will make your life brighter.
207 * Invoking guix package:: Package installation, removal, etc.
208 * Substitutes:: Downloading pre-built binaries.
209 * Packages with Multiple Outputs:: Single source package, multiple outputs.
210 * Invoking guix gc:: Running the garbage collector.
211 * Invoking guix pull:: Fetching the latest Guix and distribution.
212 * Channels:: Customizing the package collection.
213 * Invoking guix time-machine:: Running an older revision of Guix.
214 * Inferiors:: Interacting with another revision of Guix.
215 * Invoking guix describe:: Display information about your Guix revision.
216 * Invoking guix archive:: Exporting and importing store files.
220 * Official Substitute Server:: One particular source of substitutes.
221 * Substitute Server Authorization:: How to enable or disable substitutes.
222 * Substitute Authentication:: How Guix verifies substitutes.
223 * Proxy Settings:: How to get substitutes via proxy.
224 * Substitution Failure:: What happens when substitution fails.
225 * On Trusting Binaries:: How can you trust that binary blob?
229 * Invoking guix environment:: Setting up development environments.
230 * Invoking guix pack:: Creating software bundles.
231 * The GCC toolchain:: Working with languages supported by GCC.
233 Programming Interface
235 * Package Modules:: Packages from the programmer's viewpoint.
236 * Defining Packages:: Defining new packages.
237 * Build Systems:: Specifying how packages are built.
238 * The Store:: Manipulating the package store.
239 * Derivations:: Low-level interface to package derivations.
240 * The Store Monad:: Purely functional interface to the store.
241 * G-Expressions:: Manipulating build expressions.
242 * Invoking guix repl:: Programming Guix in Guile
246 * package Reference:: The package data type.
247 * origin Reference:: The origin data type.
251 * Invoking guix build:: Building packages from the command line.
252 * Invoking guix edit:: Editing package definitions.
253 * Invoking guix download:: Downloading a file and printing its hash.
254 * Invoking guix hash:: Computing the cryptographic hash of a file.
255 * Invoking guix import:: Importing package definitions.
256 * Invoking guix refresh:: Updating package definitions.
257 * Invoking guix lint:: Finding errors in package definitions.
258 * Invoking guix size:: Profiling disk usage.
259 * Invoking guix graph:: Visualizing the graph of packages.
260 * Invoking guix publish:: Sharing substitutes.
261 * Invoking guix challenge:: Challenging substitute servers.
262 * Invoking guix copy:: Copying to and from a remote store.
263 * Invoking guix container:: Process isolation.
264 * Invoking guix weather:: Assessing substitute availability.
265 * Invoking guix processes:: Listing client processes.
267 Invoking @command{guix build}
269 * Common Build Options:: Build options for most commands.
270 * Package Transformation Options:: Creating variants of packages.
271 * Additional Build Options:: Options specific to 'guix build'.
272 * Debugging Build Failures:: Real life packaging experience.
276 * Using the Configuration System:: Customizing your GNU system.
277 * operating-system Reference:: Detail of operating-system declarations.
278 * File Systems:: Configuring file system mounts.
279 * Mapped Devices:: Block device extra processing.
280 * User Accounts:: Specifying user accounts.
281 * Keyboard Layout:: How the system interprets key strokes.
282 * Locales:: Language and cultural convention settings.
283 * Services:: Specifying system services.
284 * Setuid Programs:: Programs running with root privileges.
285 * X.509 Certificates:: Authenticating HTTPS servers.
286 * Name Service Switch:: Configuring libc's name service switch.
287 * Initial RAM Disk:: Linux-Libre bootstrapping.
288 * Bootloader Configuration:: Configuring the boot loader.
289 * Invoking guix system:: Instantiating a system configuration.
290 * Invoking guix deploy:: Deploying a system configuration to a remote host.
291 * Running Guix in a VM:: How to run Guix System in a virtual machine.
292 * Defining Services:: Adding new service definitions.
296 * Base Services:: Essential system services.
297 * Scheduled Job Execution:: The mcron service.
298 * Log Rotation:: The rottlog service.
299 * Networking Services:: Network setup, SSH daemon, etc.
300 * X Window:: Graphical display.
301 * Printing Services:: Local and remote printer support.
302 * Desktop Services:: D-Bus and desktop services.
303 * Sound Services:: ALSA and Pulseaudio services.
304 * Database Services:: SQL databases, key-value stores, etc.
305 * Mail Services:: IMAP, POP3, SMTP, and all that.
306 * Messaging Services:: Messaging services.
307 * Telephony Services:: Telephony services.
308 * Monitoring Services:: Monitoring services.
309 * Kerberos Services:: Kerberos services.
310 * Web Services:: Web servers.
311 * Certificate Services:: TLS certificates via Let's Encrypt.
312 * DNS Services:: DNS daemons.
313 * VPN Services:: VPN daemons.
314 * Network File System:: NFS related services.
315 * Continuous Integration:: The Cuirass service.
316 * Power Management Services:: Extending battery life.
317 * Audio Services:: The MPD.
318 * Virtualization Services:: Virtualization services.
319 * Version Control Services:: Providing remote access to Git repositories.
320 * Game Services:: Game servers.
321 * PAM Mount Service:: Service to mount volumes when logging in.
322 * Guix Services:: Services relating specifically to Guix.
323 * Linux Services:: Services tied to the Linux kernel.
324 * Hurd Services:: Services specific to a Hurd System.
325 * Miscellaneous Services:: Other services.
329 * Service Composition:: The model for composing services.
330 * Service Types and Services:: Types and services.
331 * Service Reference:: API reference.
332 * Shepherd Services:: A particular type of service.
337 @c *********************************************************************
339 @chapter Introduction
342 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
343 using the international phonetic alphabet (IPA).} is a package
344 management tool for and distribution of the GNU system.
345 Guix makes it easy for unprivileged
346 users to install, upgrade, or remove software packages, to roll back to a
347 previous package set, to build packages from source, and generally
348 assists with the creation and maintenance of software environments.
351 @cindex GuixSD, now Guix System
352 @cindex Guix System Distribution, now Guix System
353 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
354 complements the available tools without interference (@pxref{Installation}),
355 or you can use it as a standalone operating system distribution,
356 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
357 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
358 group everything under the ``Guix'' banner since, after all, Guix System is
359 readily available through the @command{guix system} command, even if you're
360 using a different distro underneath!}. @xref{GNU Distribution}.
363 * Managing Software the Guix Way:: What's special.
364 * GNU Distribution:: The packages and tools.
367 @node Managing Software the Guix Way
368 @section Managing Software the Guix Way
370 @cindex user interfaces
371 Guix provides a command-line package management interface
372 (@pxref{Package Management}), tools to help with software development
373 (@pxref{Development}), command-line utilities for more advanced usage,
374 (@pxref{Utilities}), as well as Scheme programming interfaces
375 (@pxref{Programming Interface}).
377 Its @dfn{build daemon} is responsible for building packages on behalf of
378 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
379 binaries from authorized sources (@pxref{Substitutes}).
381 @cindex extensibility of the distribution
382 @cindex customization, of packages
383 Guix includes package definitions for many GNU and non-GNU packages, all
384 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
385 user's computing freedom}. It is @emph{extensible}: users can write
386 their own package definitions (@pxref{Defining Packages}) and make them
387 available as independent package modules (@pxref{Package Modules}). It
388 is also @emph{customizable}: users can @emph{derive} specialized package
389 definitions from existing ones, including from the command line
390 (@pxref{Package Transformation Options}).
392 @cindex functional package management
394 Under the hood, Guix implements the @dfn{functional package management}
395 discipline pioneered by Nix (@pxref{Acknowledgments}).
396 In Guix, the package build and installation process is seen
397 as a @emph{function}, in the mathematical sense. That function takes inputs,
398 such as build scripts, a compiler, and libraries, and
399 returns an installed package. As a pure function, its result depends
400 solely on its inputs---for instance, it cannot refer to software or
401 scripts that were not explicitly passed as inputs. A build function
402 always produces the same result when passed a given set of inputs. It
403 cannot alter the environment of the running system in
404 any way; for instance, it cannot create, modify, or delete files outside
405 of its build and installation directories. This is achieved by running
406 build processes in isolated environments (or @dfn{containers}), where only their
407 explicit inputs are visible.
410 The result of package build functions is @dfn{cached} in the file
411 system, in a special directory called @dfn{the store} (@pxref{The
412 Store}). Each package is installed in a directory of its own in the
413 store---by default under @file{/gnu/store}. The directory name contains
414 a hash of all the inputs used to build that package; thus, changing an
415 input yields a different directory name.
417 This approach is the foundation for the salient features of Guix: support
418 for transactional package upgrade and rollback, per-user installation, and
419 garbage collection of packages (@pxref{Features}).
422 @node GNU Distribution
423 @section GNU Distribution
426 Guix comes with a distribution of the GNU system consisting entirely of
427 free software@footnote{The term ``free'' here refers to the
428 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
429 users of that software}.}. The
430 distribution can be installed on its own (@pxref{System Installation}),
431 but it is also possible to install Guix as a package manager on top of
432 an installed GNU/Linux system (@pxref{Installation}). When we need to
433 distinguish between the two, we refer to the standalone distribution as
436 The distribution provides core GNU packages such as GNU libc, GCC, and
437 Binutils, as well as many GNU and non-GNU applications. The complete
438 list of available packages can be browsed
439 @url{https://www.gnu.org/software/guix/packages,on-line} or by
440 running @command{guix package} (@pxref{Invoking guix package}):
443 guix package --list-available
446 Our goal is to provide a practical 100% free software distribution of
447 Linux-based and other variants of GNU, with a focus on the promotion and
448 tight integration of GNU components, and an emphasis on programs and
449 tools that help users exert that freedom.
451 Packages are currently available on the following platforms:
456 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
459 Intel 32-bit architecture (IA32), Linux-Libre kernel;
462 ARMv7-A architecture with hard float, Thumb-2 and NEON,
463 using the EABI hard-float application binary interface (ABI),
464 and Linux-Libre kernel.
467 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
469 @item mips64el-linux (deprecated)
470 little-endian 64-bit MIPS processors, specifically the Loongson series,
471 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
472 supported; in particular, there is no ongoing work to ensure that this
473 architecture still works. Should someone decide they wish to revive this
474 architecture then the code is still available.
478 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
479 configuration and Guix takes care of instantiating the configuration in a
480 transactional, reproducible, and stateless fashion (@pxref{System
481 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
482 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
483 Manual}), the well-known GNU utilities and tool chain, as well as the
484 graphical environment or system services of your choice.
486 Guix System is available on all the above platforms except
487 @code{mips64el-linux}.
490 For information on porting to other architectures or kernels,
493 Building this distribution is a cooperative effort, and you are invited
494 to join! @xref{Contributing}, for information about how you can help.
497 @c *********************************************************************
499 @chapter Installation
501 @cindex installing Guix
504 We recommend the use of this
505 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
506 shell installer script} to install Guix on top of a running GNU/Linux system,
507 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
508 with the installation of the package manager, which can be done on top of a
509 running GNU/Linux system. If, instead, you want to install the complete GNU
510 operating system, @pxref{System Installation}.} The script automates the
511 download, installation, and initial configuration of Guix. It should be run
515 @cindex foreign distro
516 @cindex directories related to foreign distro
517 When installed on a foreign distro, GNU@tie{}Guix complements the available
518 tools without interference. Its data lives exclusively in two directories,
519 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
520 such as @file{/etc}, are left untouched.
522 Once installed, Guix can be updated by running @command{guix pull}
523 (@pxref{Invoking guix pull}).
525 If you prefer to perform the installation steps manually or want to tweak
526 them, you may find the following subsections useful. They describe the
527 software requirements of Guix, as well as how to install it manually and get
531 * Binary Installation:: Getting Guix running in no time!
532 * Requirements:: Software needed to build and run Guix.
533 * Running the Test Suite:: Testing Guix.
534 * Setting Up the Daemon:: Preparing the build daemon's environment.
535 * Invoking guix-daemon:: Running the build daemon.
536 * Application Setup:: Application-specific setup.
537 * Upgrading Guix:: Upgrading Guix and its build daemon.
540 @node Binary Installation
541 @section Binary Installation
543 @cindex installing Guix from binaries
544 @cindex installer script
545 This section describes how to install Guix on an arbitrary system from a
546 self-contained tarball providing binaries for Guix and for all its
547 dependencies. This is often quicker than installing from source, which
548 is described in the next sections. The only requirement is to have
551 @c Note duplicated from the ``Installation'' node.
553 We recommend the use of this
554 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
555 shell installer script}. The script automates the download, installation, and
556 initial configuration steps described below. It should be run as the root
557 user. As root, you can thus run this:
561 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
562 chmod +x guix-install.sh
567 Installing goes along these lines:
571 @cindex downloading Guix binary
572 Download the binary tarball from
573 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
574 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
575 @code{i686} (32-bits) machine already running the kernel Linux, and so on
576 (@pxref{GNU Distribution}).
578 @c The following is somewhat duplicated in ``System Installation''.
579 Make sure to download the associated @file{.sig} file and to verify the
580 authenticity of the tarball against it, along these lines:
583 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
584 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
587 If that command fails because you do not have the required public key,
588 then run this command to import it:
591 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
592 -qO - | gpg --import -
596 and rerun the @code{gpg --verify} command.
598 Take note that a warning like ``This key is not certified with a trusted
599 signature!'' is normal.
601 @c end authentication part
604 Now, you need to become the @code{root} user. Depending on your distribution,
605 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
609 # tar --warning=no-timestamp -xf \
610 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
611 # mv var/guix /var/ && mv gnu /
614 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
615 The latter contains a ready-to-use profile for @code{root} (see next
618 Do @emph{not} unpack the tarball on a working Guix system since that
619 would overwrite its own essential files.
621 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
622 not emit warnings about ``implausibly old time stamps'' (such
623 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
625 They stem from the fact that all the
626 files in the archive have their modification time set to zero (which
627 means January 1st, 1970). This is done on purpose to make sure the
628 archive content is independent of its creation time, thus making it
632 Make the profile available under @file{~root/.config/guix/current}, which is
633 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
636 # mkdir -p ~root/.config/guix
637 # ln -sf /var/guix/profiles/per-user/root/current-guix \
638 ~root/.config/guix/current
641 Source @file{etc/profile} to augment @env{PATH} and other relevant
642 environment variables:
645 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
646 source $GUIX_PROFILE/etc/profile
650 Create the group and user accounts for build users as explained below
651 (@pxref{Build Environment Setup}).
654 Run the daemon, and set it to automatically start on boot.
656 If your host distro uses the systemd init system, this can be achieved
659 @c Versions of systemd that supported symlinked service files are not
660 @c yet widely deployed, so we should suggest that users copy the service
663 @c See this thread for more information:
664 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
667 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
668 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
670 # systemctl enable --now gnu-store.mount guix-daemon
673 If your host distro uses the Upstart init system:
676 # initctl reload-configuration
677 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
682 Otherwise, you can still start the daemon manually with:
685 # ~root/.config/guix/current/bin/guix-daemon \
686 --build-users-group=guixbuild
690 Make the @command{guix} command available to other users on the machine,
694 # mkdir -p /usr/local/bin
696 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
699 It is also a good idea to make the Info version of this manual available
703 # mkdir -p /usr/local/share/info
704 # cd /usr/local/share/info
705 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
709 That way, assuming @file{/usr/local/share/info} is in the search path,
710 running @command{info guix} will open this manual (@pxref{Other Info
711 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
715 @cindex substitutes, authorization thereof
716 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
717 (@pxref{Substitutes}), authorize them:
720 # guix archive --authorize < \
721 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
725 Each user may need to perform a few additional steps to make their Guix
726 environment ready for use, @pxref{Application Setup}.
729 Voilà, the installation is complete!
731 You can confirm that Guix is working by installing a sample package into
738 The binary installation tarball can be (re)produced and verified simply
739 by running the following command in the Guix source tree:
742 make guix-binary.@var{system}.tar.xz
746 ...@: which, in turn, runs:
749 guix pack -s @var{system} --localstatedir \
750 --profile-name=current-guix guix
753 @xref{Invoking guix pack}, for more info on this handy tool.
756 @section Requirements
758 This section lists requirements when building Guix from source. The
759 build procedure for Guix is the same as for other GNU software, and is
760 not covered here. Please see the files @file{README} and @file{INSTALL}
761 in the Guix source tree for additional details.
763 @cindex official website
764 GNU Guix is available for download from its website at
765 @url{https://www.gnu.org/software/guix/}.
767 GNU Guix depends on the following packages:
770 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
772 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
775 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
776 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
777 Guile,, gnutls-guile, GnuTLS-Guile});
779 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
782 @c FIXME: Specify a version number once a release has been made.
783 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
785 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON} 3.x;
786 @item @url{https://zlib.net, zlib};
787 @item @url{https://www.gnu.org/software/make/, GNU Make}.
790 The following dependencies are optional:
794 @c Note: We need at least 0.12.0 for 'userauth-gssapi!'.
795 Support for build offloading (@pxref{Daemon Offload Setup}) and
796 @command{guix copy} (@pxref{Invoking guix copy}) depends on
797 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
798 version 0.12.0 or later.
801 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
802 substitutes can be used and @command{guix publish} can compress substitutes
806 When @url{http://www.bzip.org, libbz2} is available,
807 @command{guix-daemon} can use it to compress build logs.
810 Unless @option{--disable-daemon} was passed to @command{configure}, the
811 following packages are also needed:
814 @item @url{https://gnupg.org/, GNU libgcrypt};
815 @item @url{https://sqlite.org, SQLite 3};
816 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
820 @cindex state directory
821 When configuring Guix on a system that already has a Guix installation,
822 be sure to specify the same state directory as the existing installation
823 using the @option{--localstatedir} option of the @command{configure}
824 script (@pxref{Directory Variables, @code{localstatedir},, standards,
825 GNU Coding Standards}). Usually, this @var{localstatedir} option is
826 set to the value @file{/var}. The @command{configure} script protects
827 against unintended misconfiguration of @var{localstatedir} so you do not
828 inadvertently corrupt your store (@pxref{The Store}).
830 @node Running the Test Suite
831 @section Running the Test Suite
834 After a successful @command{configure} and @code{make} run, it is a good
835 idea to run the test suite. It can help catch issues with the setup or
836 environment, or bugs in Guix itself---and really, reporting test
837 failures is a good way to help improve the software. To run the test
844 Test cases can run in parallel: you can use the @code{-j} option of
845 GNU@tie{}make to speed things up. The first run may take a few minutes
846 on a recent machine; subsequent runs will be faster because the store
847 that is created for test purposes will already have various things in
850 It is also possible to run a subset of the tests by defining the
851 @code{TESTS} makefile variable as in this example:
854 make check TESTS="tests/store.scm tests/cpio.scm"
857 By default, tests results are displayed at a file level. In order to
858 see the details of every individual test cases, it is possible to define
859 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
862 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
865 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
866 @file{test-suite.log} file. Please specify the Guix version being used
867 as well as version numbers of the dependencies (@pxref{Requirements}) in
870 Guix also comes with a whole-system test suite that tests complete
871 Guix System instances. It can only run on systems where
872 Guix is already installed, using:
879 or, again, by defining @code{TESTS} to select a subset of tests to run:
882 make check-system TESTS="basic mcron"
885 These system tests are defined in the @code{(gnu tests @dots{})}
886 modules. They work by running the operating systems under test with
887 lightweight instrumentation in a virtual machine (VM). They can be
888 computationally intensive or rather cheap, depending on whether
889 substitutes are available for their dependencies (@pxref{Substitutes}).
890 Some of them require a lot of storage space to hold VM images.
892 Again in case of test failures, please send @email{bug-guix@@gnu.org}
895 @node Setting Up the Daemon
896 @section Setting Up the Daemon
899 Operations such as building a package or running the garbage collector
900 are all performed by a specialized process, the @dfn{build daemon}, on
901 behalf of clients. Only the daemon may access the store and its
902 associated database. Thus, any operation that manipulates the store
903 goes through the daemon. For instance, command-line tools such as
904 @command{guix package} and @command{guix build} communicate with the
905 daemon (@i{via} remote procedure calls) to instruct it what to do.
907 The following sections explain how to prepare the build daemon's
908 environment. See also @ref{Substitutes}, for information on how to allow
909 the daemon to download pre-built binaries.
912 * Build Environment Setup:: Preparing the isolated build environment.
913 * Daemon Offload Setup:: Offloading builds to remote machines.
914 * SELinux Support:: Using an SELinux policy for the daemon.
917 @node Build Environment Setup
918 @subsection Build Environment Setup
920 @cindex build environment
921 In a standard multi-user setup, Guix and its daemon---the
922 @command{guix-daemon} program---are installed by the system
923 administrator; @file{/gnu/store} is owned by @code{root} and
924 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
925 Guix tools to build packages or otherwise access the store, and the
926 daemon will do it on their behalf, ensuring that the store is kept in a
927 consistent state, and allowing built packages to be shared among users.
930 When @command{guix-daemon} runs as @code{root}, you may not want package
931 build processes themselves to run as @code{root} too, for obvious
932 security reasons. To avoid that, a special pool of @dfn{build users}
933 should be created for use by build processes started by the daemon.
934 These build users need not have a shell and a home directory: they will
935 just be used when the daemon drops @code{root} privileges in build
936 processes. Having several such users allows the daemon to launch
937 distinct build processes under separate UIDs, which guarantees that they
938 do not interfere with each other---an essential feature since builds are
939 regarded as pure functions (@pxref{Introduction}).
941 On a GNU/Linux system, a build user pool may be created like this (using
942 Bash syntax and the @code{shadow} commands):
944 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
945 @c for why `-G' is needed.
947 # groupadd --system guixbuild
948 # for i in `seq -w 1 10`;
950 useradd -g guixbuild -G guixbuild \
951 -d /var/empty -s `which nologin` \
952 -c "Guix build user $i" --system \
958 The number of build users determines how many build jobs may run in
959 parallel, as specified by the @option{--max-jobs} option
960 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
961 @command{guix system vm} and related commands, you may need to add the
962 build users to the @code{kvm} group so they can access @file{/dev/kvm},
963 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
964 (@pxref{Invoking guix system}).
966 The @code{guix-daemon} program may then be run as @code{root} with the
967 following command@footnote{If your machine uses the systemd init system,
968 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
969 file in @file{/etc/systemd/system} will ensure that
970 @command{guix-daemon} is automatically started. Similarly, if your
971 machine uses the Upstart init system, drop the
972 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
973 file in @file{/etc/init}.}:
976 # guix-daemon --build-users-group=guixbuild
981 This way, the daemon starts build processes in a chroot, under one of
982 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
983 environment contains nothing but:
985 @c Keep this list in sync with libstore/build.cc! -----------------------
988 a minimal @code{/dev} directory, created mostly independently from the
989 host @code{/dev}@footnote{``Mostly'', because while the set of files
990 that appear in the chroot's @code{/dev} is fixed, most of these files
991 can only be created if the host has them.};
994 the @code{/proc} directory; it only shows the processes of the container
995 since a separate PID name space is used;
998 @file{/etc/passwd} with an entry for the current user and an entry for
1002 @file{/etc/group} with an entry for the user's group;
1005 @file{/etc/hosts} with an entry that maps @code{localhost} to
1009 a writable @file{/tmp} directory.
1012 You can influence the directory where the daemon stores build trees
1013 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1014 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1015 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1016 This way, the value of @env{TMPDIR} does not leak inside build
1017 environments, which avoids discrepancies in cases where build processes
1018 capture the name of their build tree.
1022 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1023 environment variables for HTTP and HTTPS downloads it performs, be it
1024 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1025 (@pxref{Substitutes}).
1027 If you are installing Guix as an unprivileged user, it is still possible
1028 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1029 However, build processes will not be isolated from one another, and not
1030 from the rest of the system. Thus, build processes may interfere with
1031 each other, and may access programs, libraries, and other files
1032 available on the system---making it much harder to view them as
1033 @emph{pure} functions.
1036 @node Daemon Offload Setup
1037 @subsection Using the Offload Facility
1041 When desired, the build daemon can @dfn{offload} derivation builds to
1042 other machines running Guix, using the @code{offload} @dfn{build
1043 hook}@footnote{This feature is available only when
1044 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1045 present.}. When that
1046 feature is enabled, a list of user-specified build machines is read from
1047 @file{/etc/guix/machines.scm}; every time a build is requested, for
1048 instance via @code{guix build}, the daemon attempts to offload it to one
1049 of the machines that satisfy the constraints of the derivation, in
1050 particular its system type---e.g., @file{x86_64-linux}. Missing
1051 prerequisites for the build are copied over SSH to the target machine,
1052 which then proceeds with the build; upon success the output(s) of the
1053 build are copied back to the initial machine.
1055 The @file{/etc/guix/machines.scm} file typically looks like this:
1058 (list (build-machine
1059 (name "eightysix.example.org")
1060 (system "x86_64-linux")
1061 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1063 (speed 2.)) ;incredibly fast!
1066 (name "armeight.example.org")
1067 (system "aarch64-linux")
1068 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1071 (string-append (getenv "HOME")
1072 "/.ssh/identity-for-guix"))))
1076 In the example above we specify a list of two build machines, one for
1077 the @code{x86_64} architecture and one for the @code{aarch64}
1080 In fact, this file is---not surprisingly!---a Scheme file that is
1081 evaluated when the @code{offload} hook is started. Its return value
1082 must be a list of @code{build-machine} objects. While this example
1083 shows a fixed list of build machines, one could imagine, say, using
1084 DNS-SD to return a list of potential build machines discovered in the
1085 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1086 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1089 @deftp {Data Type} build-machine
1090 This data type represents build machines to which the daemon may offload
1091 builds. The important fields are:
1096 The host name of the remote machine.
1099 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1102 The user account to use when connecting to the remote machine over SSH.
1103 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1104 allow non-interactive logins.
1107 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1108 This is used to authenticate the machine when we connect to it. It is a
1109 long string that looks like this:
1112 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1115 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1116 key can be found in a file such as
1117 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1119 If the machine is running the SSH daemon of GNU@tie{}lsh,
1120 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1121 similar file. It can be converted to the OpenSSH format using
1122 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1125 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1126 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1131 A number of optional fields may be specified:
1135 @item @code{port} (default: @code{22})
1136 Port number of SSH server on the machine.
1138 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1139 The SSH private key file to use when connecting to the machine, in
1140 OpenSSH format. This key must not be protected with a passphrase.
1142 Note that the default value is the private key @emph{of the root
1143 account}. Make sure it exists if you use the default.
1145 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1146 @itemx @code{compression-level} (default: @code{3})
1147 The SSH-level compression methods and compression level requested.
1149 Note that offloading relies on SSH compression to reduce bandwidth usage
1150 when transferring files to and from build machines.
1152 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1153 File name of the Unix-domain socket @command{guix-daemon} is listening
1156 @item @code{parallel-builds} (default: @code{1})
1157 The number of builds that may run in parallel on the machine.
1159 @item @code{speed} (default: @code{1.0})
1160 A ``relative speed factor''. The offload scheduler will tend to prefer
1161 machines with a higher speed factor.
1163 @item @code{features} (default: @code{'()})
1164 A list of strings denoting specific features supported by the machine.
1165 An example is @code{"kvm"} for machines that have the KVM Linux modules
1166 and corresponding hardware support. Derivations can request features by
1167 name, and they will be scheduled on matching build machines.
1172 The @command{guix} command must be in the search path on the build
1173 machines. You can check whether this is the case by running:
1176 ssh build-machine guix repl --version
1179 There is one last thing to do once @file{machines.scm} is in place. As
1180 explained above, when offloading, files are transferred back and forth
1181 between the machine stores. For this to work, you first need to
1182 generate a key pair on each machine to allow the daemon to export signed
1183 archives of files from the store (@pxref{Invoking guix archive}):
1186 # guix archive --generate-key
1190 Each build machine must authorize the key of the master machine so that
1191 it accepts store items it receives from the master:
1194 # guix archive --authorize < master-public-key.txt
1198 Likewise, the master machine must authorize the key of each build machine.
1200 All the fuss with keys is here to express pairwise mutual trust
1201 relations between the master and the build machines. Concretely, when
1202 the master receives files from a build machine (and @i{vice versa}), its
1203 build daemon can make sure they are genuine, have not been tampered
1204 with, and that they are signed by an authorized key.
1206 @cindex offload test
1207 To test whether your setup is operational, run this command on the
1214 This will attempt to connect to each of the build machines specified in
1215 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1216 available on each machine, attempt to export to the machine and import
1217 from it, and report any error in the process.
1219 If you want to test a different machine file, just specify it on the
1223 # guix offload test machines-qualif.scm
1226 Last, you can test the subset of the machines whose name matches a
1227 regular expression like this:
1230 # guix offload test machines.scm '\.gnu\.org$'
1233 @cindex offload status
1234 To display the current load of all build hosts, run this command on the
1238 # guix offload status
1242 @node SELinux Support
1243 @subsection SELinux Support
1245 @cindex SELinux, daemon policy
1246 @cindex mandatory access control, SELinux
1247 @cindex security, guix-daemon
1248 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1249 can be installed on a system where SELinux is enabled, in order to label
1250 Guix files and to specify the expected behavior of the daemon. Since
1251 Guix System does not provide an SELinux base policy, the daemon policy cannot
1252 be used on Guix System.
1254 @subsubsection Installing the SELinux policy
1255 @cindex SELinux, policy installation
1256 To install the policy run this command as root:
1259 semodule -i etc/guix-daemon.cil
1262 Then relabel the file system with @code{restorecon} or by a different
1263 mechanism provided by your system.
1265 Once the policy is installed, the file system has been relabeled, and
1266 the daemon has been restarted, it should be running in the
1267 @code{guix_daemon_t} context. You can confirm this with the following
1271 ps -Zax | grep guix-daemon
1274 Monitor the SELinux log files as you run a command like @code{guix build
1275 hello} to convince yourself that SELinux permits all necessary
1278 @subsubsection Limitations
1279 @cindex SELinux, limitations
1281 This policy is not perfect. Here is a list of limitations or quirks
1282 that should be considered when deploying the provided SELinux policy for
1287 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1288 operations involve contexts that have anything to do with
1289 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1290 but it would be preferrable to define socket rules for only this label.
1293 @code{guix gc} cannot access arbitrary links to profiles. By design,
1294 the file label of the destination of a symlink is independent of the
1295 file label of the link itself. Although all profiles under
1296 $localstatedir are labelled, the links to these profiles inherit the
1297 label of the directory they are in. For links in the user’s home
1298 directory this will be @code{user_home_t}. But for links from the root
1299 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1300 directory, etc, this won’t work. @code{guix gc} would be prevented from
1301 reading and following these links.
1304 The daemon’s feature to listen for TCP connections might no longer work.
1305 This might require extra rules, because SELinux treats network sockets
1306 differently from files.
1309 Currently all files with a name matching the regular expression
1310 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1311 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1312 that name in any profile would be permitted to run in the
1313 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1314 build a package that provides this executable and convince a user to
1315 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1316 At that point SELinux could not prevent it from accessing files that are
1317 allowed for processes in that domain.
1319 We could generate a much more restrictive policy at installation time,
1320 so that only the @emph{exact} file name of the currently installed
1321 @code{guix-daemon} executable would be labelled with
1322 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1323 The downside is that root would have to install or upgrade the policy at
1324 installation time whenever the Guix package that provides the
1325 effectively running @code{guix-daemon} executable is upgraded.
1328 @node Invoking guix-daemon
1329 @section Invoking @command{guix-daemon}
1331 The @command{guix-daemon} program implements all the functionality to
1332 access the store. This includes launching build processes, running the
1333 garbage collector, querying the availability of a build result, etc. It
1334 is normally run as @code{root} like this:
1337 # guix-daemon --build-users-group=guixbuild
1341 For details on how to set it up, @pxref{Setting Up the Daemon}.
1344 @cindex container, build environment
1345 @cindex build environment
1346 @cindex reproducible builds
1347 By default, @command{guix-daemon} launches build processes under
1348 different UIDs, taken from the build group specified with
1349 @option{--build-users-group}. In addition, each build process is run in a
1350 chroot environment that only contains the subset of the store that the
1351 build process depends on, as specified by its derivation
1352 (@pxref{Programming Interface, derivation}), plus a set of specific
1353 system directories. By default, the latter contains @file{/dev} and
1354 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1355 @dfn{container}: in addition to having its own file system tree, it has
1356 a separate mount name space, its own PID name space, network name space,
1357 etc. This helps achieve reproducible builds (@pxref{Features}).
1359 When the daemon performs a build on behalf of the user, it creates a
1360 build directory under @file{/tmp} or under the directory specified by
1361 its @env{TMPDIR} environment variable. This directory is shared with
1362 the container for the duration of the build, though within the container,
1363 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1365 The build directory is automatically deleted upon completion, unless the
1366 build failed and the client specified @option{--keep-failed}
1367 (@pxref{Invoking guix build, @option{--keep-failed}}).
1369 The daemon listens for connections and spawns one sub-process for each session
1370 started by a client (one of the @command{guix} sub-commands). The
1371 @command{guix processes} command allows you to get an overview of the activity
1372 on your system by viewing each of the active sessions and clients.
1373 @xref{Invoking guix processes}, for more information.
1375 The following command-line options are supported:
1378 @item --build-users-group=@var{group}
1379 Take users from @var{group} to run build processes (@pxref{Setting Up
1380 the Daemon, build users}).
1382 @item --no-substitutes
1384 Do not use substitutes for build products. That is, always build things
1385 locally instead of allowing downloads of pre-built binaries
1386 (@pxref{Substitutes}).
1388 When the daemon runs with @option{--no-substitutes}, clients can still
1389 explicitly enable substitution @i{via} the @code{set-build-options}
1390 remote procedure call (@pxref{The Store}).
1392 @item --substitute-urls=@var{urls}
1393 @anchor{daemon-substitute-urls}
1394 Consider @var{urls} the default whitespace-separated list of substitute
1395 source URLs. When this option is omitted,
1396 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1398 This means that substitutes may be downloaded from @var{urls}, as long
1399 as they are signed by a trusted signature (@pxref{Substitutes}).
1403 Do not use offload builds to other machines (@pxref{Daemon Offload
1404 Setup}). That is, always build things locally instead of offloading
1405 builds to remote machines.
1407 @item --cache-failures
1408 Cache build failures. By default, only successful builds are cached.
1410 When this option is used, @command{guix gc --list-failures} can be used
1411 to query the set of store items marked as failed; @command{guix gc
1412 --clear-failures} removes store items from the set of cached failures.
1413 @xref{Invoking guix gc}.
1415 @item --cores=@var{n}
1417 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1420 The default value is @code{0}, but it may be overridden by clients, such
1421 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1424 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1425 in the build process, which can then use it to exploit internal
1426 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1428 @item --max-jobs=@var{n}
1430 Allow at most @var{n} build jobs in parallel. The default value is
1431 @code{1}. Setting it to @code{0} means that no builds will be performed
1432 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1433 Setup}), or simply fail.
1435 @item --max-silent-time=@var{seconds}
1436 When the build or substitution process remains silent for more than
1437 @var{seconds}, terminate it and report a build failure.
1439 The default value is @code{0}, which disables the timeout.
1441 The value specified here can be overridden by clients (@pxref{Common
1442 Build Options, @option{--max-silent-time}}).
1444 @item --timeout=@var{seconds}
1445 Likewise, when the build or substitution process lasts for more than
1446 @var{seconds}, terminate it and report a build failure.
1448 The default value is @code{0}, which disables the timeout.
1450 The value specified here can be overridden by clients (@pxref{Common
1451 Build Options, @option{--timeout}}).
1453 @item --rounds=@var{N}
1454 Build each derivation @var{n} times in a row, and raise an error if
1455 consecutive build results are not bit-for-bit identical. Note that this
1456 setting can be overridden by clients such as @command{guix build}
1457 (@pxref{Invoking guix build}).
1459 When used in conjunction with @option{--keep-failed}, the differing
1460 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1461 This makes it easy to look for differences between the two results.
1464 Produce debugging output.
1466 This is useful to debug daemon start-up issues, but then it may be
1467 overridden by clients, for example the @option{--verbosity} option of
1468 @command{guix build} (@pxref{Invoking guix build}).
1470 @item --chroot-directory=@var{dir}
1471 Add @var{dir} to the build chroot.
1473 Doing this may change the result of build processes---for instance if
1474 they use optional dependencies found in @var{dir} when it is available,
1475 and not otherwise. For that reason, it is not recommended to do so.
1476 Instead, make sure that each derivation declares all the inputs that it
1479 @item --disable-chroot
1480 Disable chroot builds.
1482 Using this option is not recommended since, again, it would allow build
1483 processes to gain access to undeclared dependencies. It is necessary,
1484 though, when @command{guix-daemon} is running under an unprivileged user
1487 @item --log-compression=@var{type}
1488 Compress build logs according to @var{type}, one of @code{gzip},
1489 @code{bzip2}, or @code{none}.
1491 Unless @option{--lose-logs} is used, all the build logs are kept in the
1492 @var{localstatedir}. To save space, the daemon automatically compresses
1493 them with Bzip2 by default.
1495 @item --disable-deduplication
1496 @cindex deduplication
1497 Disable automatic file ``deduplication'' in the store.
1499 By default, files added to the store are automatically ``deduplicated'':
1500 if a newly added file is identical to another one found in the store,
1501 the daemon makes the new file a hard link to the other file. This can
1502 noticeably reduce disk usage, at the expense of slightly increased
1503 input/output load at the end of a build process. This option disables
1506 @item --gc-keep-outputs[=yes|no]
1507 Tell whether the garbage collector (GC) must keep outputs of live
1511 @cindex garbage collector roots
1512 When set to @code{yes}, the GC will keep the outputs of any live
1513 derivation available in the store---the @file{.drv} files. The default
1514 is @code{no}, meaning that derivation outputs are kept only if they are
1515 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1518 @item --gc-keep-derivations[=yes|no]
1519 Tell whether the garbage collector (GC) must keep derivations
1520 corresponding to live outputs.
1522 When set to @code{yes}, as is the case by default, the GC keeps
1523 derivations---i.e., @file{.drv} files---as long as at least one of their
1524 outputs is live. This allows users to keep track of the origins of
1525 items in their store. Setting it to @code{no} saves a bit of disk
1528 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1529 liveness to flow from outputs to derivations, and setting
1530 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1531 derivations to outputs. When both are set to @code{yes}, the effect is
1532 to keep all the build prerequisites (the sources, compiler, libraries,
1533 and other build-time tools) of live objects in the store, regardless of
1534 whether these prerequisites are reachable from a GC root. This is
1535 convenient for developers since it saves rebuilds or downloads.
1537 @item --impersonate-linux-2.6
1538 On Linux-based systems, impersonate Linux 2.6. This means that the
1539 kernel's @command{uname} system call will report 2.6 as the release number.
1541 This might be helpful to build programs that (usually wrongfully) depend
1542 on the kernel version number.
1545 Do not keep build logs. By default they are kept under
1546 @file{@var{localstatedir}/guix/log}.
1548 @item --system=@var{system}
1549 Assume @var{system} as the current system type. By default it is the
1550 architecture/kernel pair found at configure time, such as
1551 @code{x86_64-linux}.
1553 @item --listen=@var{endpoint}
1554 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1555 as the file name of a Unix-domain socket if it starts with
1556 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1557 host name or host name and port to listen to. Here are a few examples:
1560 @item --listen=/gnu/var/daemon
1561 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1562 creating it if needed.
1564 @item --listen=localhost
1565 @cindex daemon, remote access
1566 @cindex remote access to the daemon
1567 @cindex daemon, cluster setup
1568 @cindex clusters, daemon setup
1569 Listen for TCP connections on the network interface corresponding to
1570 @code{localhost}, on port 44146.
1572 @item --listen=128.0.0.42:1234
1573 Listen for TCP connections on the network interface corresponding to
1574 @code{128.0.0.42}, on port 1234.
1577 This option can be repeated multiple times, in which case
1578 @command{guix-daemon} accepts connections on all the specified
1579 endpoints. Users can tell client commands what endpoint to connect to
1580 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1581 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1584 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1585 @option{--listen=@var{host}} is suitable on local networks, such as
1586 clusters, where only trusted nodes may connect to the build daemon. In
1587 other cases where remote access to the daemon is needed, we recommend
1588 using Unix-domain sockets along with SSH.
1591 When @option{--listen} is omitted, @command{guix-daemon} listens for
1592 connections on the Unix-domain socket located at
1593 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1597 @node Application Setup
1598 @section Application Setup
1600 @cindex foreign distro
1601 When using Guix on top of GNU/Linux distribution other than Guix System---a
1602 so-called @dfn{foreign distro}---a few additional steps are needed to
1603 get everything in place. Here are some of them.
1607 @anchor{locales-and-locpath}
1608 @cindex locales, when not on Guix System
1610 @vindex GUIX_LOCPATH
1611 Packages installed @i{via} Guix will not use the locale data of the
1612 host system. Instead, you must first install one of the locale packages
1613 available with Guix and then define the @env{GUIX_LOCPATH} environment
1617 $ guix install glibc-locales
1618 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1621 Note that the @code{glibc-locales} package contains data for all the
1622 locales supported by the GNU@tie{}libc and weighs in at around
1623 917@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1624 limited to a few UTF-8 locales.
1626 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1627 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1628 Manual}). There are two important differences though:
1632 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1633 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1634 to make sure the programs of the foreign distro will not end up loading
1635 incompatible locale data.
1638 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1639 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1640 should your Guix profile contain a mixture of programs linked against
1641 different libc version, each libc version will only try to load locale
1642 data in the right format.
1645 This is important because the locale data format used by different libc
1646 versions may be incompatible.
1648 @subsection Name Service Switch
1650 @cindex name service switch, glibc
1651 @cindex NSS (name service switch), glibc
1652 @cindex nscd (name service caching daemon)
1653 @cindex name service caching daemon (nscd)
1654 When using Guix on a foreign distro, we @emph{strongly recommend} that
1655 the system run the GNU C library's @dfn{name service cache daemon},
1656 @command{nscd}, which should be listening on the
1657 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1658 installed with Guix may fail to look up host names or user accounts, or
1659 may even crash. The next paragraphs explain why.
1661 @cindex @file{nsswitch.conf}
1662 The GNU C library implements a @dfn{name service switch} (NSS), which is
1663 an extensible mechanism for ``name lookups'' in general: host name
1664 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1665 The GNU C Library Reference Manual}).
1667 @cindex Network information service (NIS)
1668 @cindex NIS (Network information service)
1669 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1670 lookup implementations: for example, the @code{nss-mdns} plugin allow
1671 resolution of @code{.local} host names, the @code{nis} plugin allows
1672 user account lookup using the Network information service (NIS), and so
1673 on. These extra ``lookup services'' are configured system-wide in
1674 @file{/etc/nsswitch.conf}, and all the programs running on the system
1675 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1678 When they perform a name lookup---for instance by calling the
1679 @code{getaddrinfo} function in C---applications first try to connect to
1680 the nscd; on success, nscd performs name lookups on their behalf. If
1681 the nscd is not running, then they perform the name lookup by
1682 themselves, by loading the name lookup services into their own address
1683 space and running it. These name lookup services---the
1684 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1685 the host system's C library, rather than from the C library the
1686 application is linked against (the C library coming from Guix).
1688 And this is where the problem is: if your application is linked against
1689 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1690 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1691 likely crash or have its name lookups fail unexpectedly.
1693 Running @command{nscd} on the system, among other advantages, eliminates
1694 this binary incompatibility problem because those @code{libnss_*.so}
1695 files are loaded in the @command{nscd} process, not in applications
1698 @subsection X11 Fonts
1701 The majority of graphical applications use Fontconfig to locate and
1702 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1703 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1704 by default. Thus, to allow graphical applications installed with Guix
1705 to display fonts, you have to install fonts with Guix as well.
1706 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1707 @code{font-gnu-freefont}.
1709 @cindex @code{fc-cache}
1711 Once you have installed or removed fonts, or when you notice an
1712 application that does not find fonts, you may need to install Fontconfig
1713 and to force an update of its font cache by running:
1716 guix install fontconfig
1720 To display text written in Chinese languages, Japanese, or Korean in
1721 graphical applications, consider installing
1722 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1723 has multiple outputs, one per language family (@pxref{Packages with
1724 Multiple Outputs}). For instance, the following command installs fonts
1725 for Chinese languages:
1728 guix install font-adobe-source-han-sans:cn
1731 @cindex @code{xterm}
1732 Older programs such as @command{xterm} do not use Fontconfig and instead
1733 rely on server-side font rendering. Such programs require to specify a
1734 full name of a font using XLFD (X Logical Font Description), like this:
1737 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1740 To be able to use such full names for the TrueType fonts installed in
1741 your Guix profile, you need to extend the font path of the X server:
1743 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1744 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1746 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1749 @cindex @code{xlsfonts}
1750 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1751 to make sure your TrueType fonts are listed there.
1754 @subsection X.509 Certificates
1756 @cindex @code{nss-certs}
1757 The @code{nss-certs} package provides X.509 certificates, which allow
1758 programs to authenticate Web servers accessed over HTTPS.
1760 When using Guix on a foreign distro, you can install this package and
1761 define the relevant environment variables so that packages know where to
1762 look for certificates. @xref{X.509 Certificates}, for detailed
1765 @subsection Emacs Packages
1767 @cindex @code{emacs}
1768 When you install Emacs packages with Guix, the Elisp files are placed
1769 under the @file{share/emacs/site-lisp/} directory of the profile in
1770 which they are installed. The Elisp libraries are made available to
1771 Emacs through the @env{EMACSLOADPATH} environment variable, which is
1772 set when installing Emacs itself.
1774 Additionally, autoload definitions are automatically evaluated at the
1775 initialization of Emacs, by the Guix-specific
1776 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1777 want to avoid auto-loading the Emacs packages installed with Guix, you
1778 can do so by running Emacs with the @option{--no-site-file} option
1779 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1782 @node Upgrading Guix
1783 @section Upgrading Guix
1785 @cindex Upgrading Guix, on a foreign distro
1787 To upgrade Guix, run:
1793 @xref{Invoking guix pull}, for more information.
1795 @cindex upgrading Guix for the root user, on a foreign distro
1796 @cindex upgrading the Guix daemon, on a foreign distro
1797 @cindex @command{guix pull} for the root user, on a foreign distro
1799 On a foreign distro, you can upgrade the build daemon by running:
1806 followed by (assuming your distro uses the systemd service management
1810 systemctl restart guix-daemon.service
1813 On Guix System, upgrading the daemon is achieved by reconfiguring the
1814 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1818 @c *********************************************************************
1819 @node System Installation
1820 @chapter System Installation
1822 @cindex installing Guix System
1823 @cindex Guix System, installation
1824 This section explains how to install Guix System
1825 on a machine. Guix, as a package manager, can
1826 also be installed on top of a running GNU/Linux system,
1827 @pxref{Installation}.
1831 @c This paragraph is for people reading this from tty2 of the
1832 @c installation image.
1833 You are reading this documentation with an Info reader. For details on
1834 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1835 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1836 Info}. Hit @kbd{l} afterwards to come back here.
1838 Alternatively, run @command{info info} in another tty to keep the manual
1844 * Limitations:: What you can expect.
1845 * Hardware Considerations:: Supported hardware.
1846 * USB Stick and DVD Installation:: Preparing the installation medium.
1847 * Preparing for Installation:: Networking, partitioning, etc.
1848 * Guided Graphical Installation:: Easy graphical installation.
1849 * Manual Installation:: Manual installation for wizards.
1850 * After System Installation:: When installation succeeded.
1851 * Installing Guix in a VM:: Guix System playground.
1852 * Building the Installation Image:: How this comes to be.
1856 @section Limitations
1858 We consider Guix System to be ready for a wide range of ``desktop'' and server
1859 use cases. The reliability guarantees it provides---transactional upgrades
1860 and rollbacks, reproducibility---make it a solid foundation.
1862 Nevertheless, before you proceed with the installation, be aware of the
1863 following noteworthy limitations applicable to version @value{VERSION}:
1867 Support for the Logical Volume Manager (LVM) is missing.
1870 More and more system services are provided (@pxref{Services}), but some
1874 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1875 as well as a number of X11 window managers. However, KDE is currently
1879 More than a disclaimer, this is an invitation to report issues (and success
1880 stories!), and to join us in improving it. @xref{Contributing}, for more
1884 @node Hardware Considerations
1885 @section Hardware Considerations
1887 @cindex hardware support on Guix System
1888 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1889 builds around the kernel Linux-libre, which means that only hardware for
1890 which free software drivers and firmware exist is supported. Nowadays,
1891 a wide range of off-the-shelf hardware is supported on
1892 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1893 Ethernet controllers. Unfortunately, there are still areas where
1894 hardware vendors deny users control over their own computing, and such
1895 hardware is not supported on Guix System.
1897 @cindex WiFi, hardware support
1898 One of the main areas where free drivers or firmware are lacking is WiFi
1899 devices. WiFi devices known to work include those using Atheros chips
1900 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1901 driver, and those using Broadcom/AirForce chips (BCM43xx with
1902 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1903 Linux-libre driver. Free firmware exists for both and is available
1904 out-of-the-box on Guix System, as part of @code{%base-firmware}
1905 (@pxref{operating-system Reference, @code{firmware}}).
1907 @cindex RYF, Respects Your Freedom
1908 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1909 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1910 certification program for hardware products that respect your freedom
1911 and your privacy and ensure that you have control over your device. We
1912 encourage you to check the list of RYF-certified devices.
1914 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1915 web site. It contains a catalog of hardware devices with information
1916 about their support in GNU/Linux.
1919 @node USB Stick and DVD Installation
1920 @section USB Stick and DVD Installation
1922 An ISO-9660 installation image that can be written to a USB stick or
1923 burnt to a DVD can be downloaded from
1924 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz},
1925 where you can replace @code{x86_64-linux} with one of:
1929 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1932 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1935 @c start duplication of authentication part from ``Binary Installation''
1936 Make sure to download the associated @file{.sig} file and to verify the
1937 authenticity of the image against it, along these lines:
1940 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
1941 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
1944 If that command fails because you do not have the required public key,
1945 then run this command to import it:
1948 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1949 -qO - | gpg --import -
1953 and rerun the @code{gpg --verify} command.
1955 Take note that a warning like ``This key is not certified with a trusted
1956 signature!'' is normal.
1960 This image contains the tools necessary for an installation.
1961 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1963 @unnumberedsubsec Copying to a USB Stick
1965 To copy the image to a USB stick, follow these steps:
1969 Decompress the image using the @command{xz} command:
1972 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
1976 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1977 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1978 copy the image with:
1981 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX
1985 Access to @file{/dev/sdX} usually requires root privileges.
1988 @unnumberedsubsec Burning on a DVD
1990 To copy the image to a DVD, follow these steps:
1994 Decompress the image using the @command{xz} command:
1997 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
2001 Insert a blank DVD into your machine, and determine
2002 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2003 copy the image with:
2006 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2009 Access to @file{/dev/srX} usually requires root privileges.
2012 @unnumberedsubsec Booting
2014 Once this is done, you should be able to reboot the system and boot from
2015 the USB stick or DVD. The latter usually requires you to get in the
2016 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2017 In order to boot from Libreboot, switch to the command mode by pressing
2018 the @kbd{c} key and type @command{search_grub usb}.
2020 @xref{Installing Guix in a VM}, if, instead, you would like to install
2021 Guix System in a virtual machine (VM).
2024 @node Preparing for Installation
2025 @section Preparing for Installation
2027 Once you have booted, you can use the guided graphical installer, which makes
2028 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2029 if you are already familiar with GNU/Linux and if you want more control than
2030 what the graphical installer provides, you can choose the ``manual''
2031 installation process (@pxref{Manual Installation}).
2033 The graphical installer is available on TTY1. You can obtain root shells on
2034 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2035 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2036 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2037 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2038 which allows you to select text with the left mouse button and to paste it
2039 with the middle button.
2042 Installation requires access to the Internet so that any missing
2043 dependencies of your system configuration can be downloaded. See the
2044 ``Networking'' section below.
2047 @node Guided Graphical Installation
2048 @section Guided Graphical Installation
2050 The graphical installer is a text-based user interface. It will guide you,
2051 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2053 The first dialog boxes allow you to set up the system as you use it during the
2054 installation: you can choose the language, keyboard layout, and set up
2055 networking, which will be used during the installation. The image below shows
2056 the networking dialog.
2058 @image{images/installer-network,5in,, networking setup with the graphical installer}
2060 Later steps allow you to partition your hard disk, as shown in the image
2061 below, to choose whether or not to use encrypted file systems, to enter the
2062 host name and root password, and to create an additional account, among other
2065 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2067 Note that, at any time, the installer allows you to exit the current
2068 installation step and resume at a previous step, as show in the image below.
2070 @image{images/installer-resume,5in,, resuming the installation process}
2072 Once you're done, the installer produces an operating system configuration and
2073 displays it (@pxref{Using the Configuration System}). At that point you can
2074 hit ``OK'' and installation will proceed. On success, you can reboot into the
2075 new system and enjoy. @xref{After System Installation}, for what's next!
2078 @node Manual Installation
2079 @section Manual Installation
2081 This section describes how you would ``manually'' install GNU@tie{}Guix System
2082 on your machine. This option requires familiarity with GNU/Linux, with the
2083 shell, and with common administration tools. If you think this is not for
2084 you, consider using the guided graphical installer (@pxref{Guided Graphical
2087 The installation system provides root shells on TTYs 3 to 6; press
2088 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2089 many common tools needed to install the system. But it is also a full-blown
2090 Guix System, which means that you can install additional packages, should you
2091 need it, using @command{guix package} (@pxref{Invoking guix package}).
2094 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2095 * Proceeding with the Installation:: Installing.
2098 @node Keyboard Layout and Networking and Partitioning
2099 @subsection Keyboard Layout, Networking, and Partitioning
2101 Before you can install the system, you may want to adjust the keyboard layout,
2102 set up networking, and partition your target hard disk. This section will
2103 guide you through this.
2105 @subsubsection Keyboard Layout
2107 @cindex keyboard layout
2108 The installation image uses the US qwerty keyboard layout. If you want
2109 to change it, you can use the @command{loadkeys} command. For example,
2110 the following command selects the Dvorak keyboard layout:
2116 See the files under @file{/run/current-system/profile/share/keymaps} for
2117 a list of available keyboard layouts. Run @command{man loadkeys} for
2120 @subsubsection Networking
2122 Run the following command to see what your network interfaces are called:
2129 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2135 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2136 Wired interfaces have a name starting with @samp{e}; for example, the
2137 interface corresponding to the first on-board Ethernet controller is
2138 called @samp{eno1}. Wireless interfaces have a name starting with
2139 @samp{w}, like @samp{w1p2s0}.
2142 @item Wired connection
2143 To configure a wired network run the following command, substituting
2144 @var{interface} with the name of the wired interface you want to use.
2147 ifconfig @var{interface} up
2151 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2154 ip link set @var{interface} up
2157 @item Wireless connection
2160 To configure wireless networking, you can create a configuration file
2161 for the @command{wpa_supplicant} configuration tool (its location is not
2162 important) using one of the available text editors such as
2166 nano wpa_supplicant.conf
2169 As an example, the following stanza can go to this file and will work
2170 for many wireless networks, provided you give the actual SSID and
2171 passphrase for the network you are connecting to:
2175 ssid="@var{my-ssid}"
2177 psk="the network's secret passphrase"
2181 Start the wireless service and run it in the background with the
2182 following command (substitute @var{interface} with the name of the
2183 network interface you want to use):
2186 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2189 Run @command{man wpa_supplicant} for more information.
2193 At this point, you need to acquire an IP address. On a network where IP
2194 addresses are automatically assigned @i{via} DHCP, you can run:
2197 dhclient -v @var{interface}
2200 Try to ping a server to see if networking is up and running:
2206 Setting up network access is almost always a requirement because the
2207 image does not contain all the software and tools that may be needed.
2209 @cindex proxy, during system installation
2210 If you need HTTP and HTTPS access to go through a proxy, run the
2214 herd set-http-proxy guix-daemon @var{URL}
2218 where @var{URL} is the proxy URL, for example
2219 @code{http://example.org:8118}.
2221 @cindex installing over SSH
2222 If you want to, you can continue the installation remotely by starting
2226 herd start ssh-daemon
2229 Make sure to either set a password with @command{passwd}, or configure
2230 OpenSSH public key authentication before logging in.
2232 @subsubsection Disk Partitioning
2234 Unless this has already been done, the next step is to partition, and
2235 then format the target partition(s).
2237 The installation image includes several partitioning tools, including
2238 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2239 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2240 the partition layout you want:
2246 If your disk uses the GUID Partition Table (GPT) format and you plan to
2247 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2248 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2251 @cindex EFI, installation
2252 @cindex UEFI, installation
2253 @cindex ESP, EFI system partition
2254 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2255 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2256 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2259 parted /dev/sda set 1 esp on
2263 @vindex grub-bootloader
2264 @vindex grub-efi-bootloader
2265 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2266 @file{/sys/firmware/efi} exists in the installation image, then you should
2267 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2268 Otherwise you should use the BIOS-based GRUB, known as
2269 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2273 Once you are done partitioning the target hard disk drive, you have to
2274 create a file system on the relevant partition(s)@footnote{Currently
2275 Guix System only supports ext4, btrfs, and JFS file systems. In particular,
2276 code that reads file system UUIDs and labels only works for these file system
2277 types.}. For the ESP, if you have one and assuming it is
2278 @file{/dev/sda1}, run:
2281 mkfs.fat -F32 /dev/sda1
2284 For the root file system, ext4 is the most widely used format. Other
2285 file systems, such as Btrfs, support compression, which is reported to
2286 nicely complement file deduplication that the daemon performs
2287 independently of the file system (@pxref{Invoking guix-daemon,
2290 Preferably, assign file systems a label so that you can easily and
2291 reliably refer to them in @code{file-system} declarations (@pxref{File
2292 Systems}). This is typically done using the @code{-L} option of
2293 @command{mkfs.ext4} and related commands. So, assuming the target root
2294 partition lives at @file{/dev/sda2}, a file system with the label
2295 @code{my-root} can be created with:
2298 mkfs.ext4 -L my-root /dev/sda2
2301 @cindex encrypted disk
2302 If you are instead planning to encrypt the root partition, you can use
2303 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2304 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2305 @code{man cryptsetup}} for more information). Assuming you want to
2306 store the root partition on @file{/dev/sda2}, the command sequence would
2307 be along these lines:
2310 cryptsetup luksFormat /dev/sda2
2311 cryptsetup open --type luks /dev/sda2 my-partition
2312 mkfs.ext4 -L my-root /dev/mapper/my-partition
2315 Once that is done, mount the target file system under @file{/mnt}
2316 with a command like (again, assuming @code{my-root} is the label of the
2320 mount LABEL=my-root /mnt
2323 Also mount any other file systems you would like to use on the target
2324 system relative to this path. If you have opted for @file{/boot/efi} as an
2325 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2326 found by @code{guix system init} afterwards.
2328 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2329 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2330 sure to initialize them with @command{mkswap}. Assuming you have one
2331 swap partition on @file{/dev/sda3}, you would run:
2338 Alternatively, you may use a swap file. For example, assuming that in
2339 the new system you want to use the file @file{/swapfile} as a swap file,
2340 you would run@footnote{This example will work for many types of file
2341 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2342 btrfs), the required steps may be different. For details, see the
2343 manual pages for @command{mkswap} and @command{swapon}.}:
2346 # This is 10 GiB of swap space. Adjust "count" to change the size.
2347 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2348 # For security, make the file readable and writable only by root.
2349 chmod 600 /mnt/swapfile
2350 mkswap /mnt/swapfile
2351 swapon /mnt/swapfile
2354 Note that if you have encrypted the root partition and created a swap
2355 file in its file system as described above, then the encryption also
2356 protects the swap file, just like any other file in that file system.
2358 @node Proceeding with the Installation
2359 @subsection Proceeding with the Installation
2361 With the target partitions ready and the target root mounted on
2362 @file{/mnt}, we're ready to go. First, run:
2365 herd start cow-store /mnt
2368 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2369 during the installation phase are written to the target disk on @file{/mnt}
2370 rather than kept in memory. This is necessary because the first phase of
2371 the @command{guix system init} command (see below) entails downloads or
2372 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2374 Next, you have to edit a file and
2375 provide the declaration of the operating system to be installed. To
2376 that end, the installation system comes with three text editors. We
2377 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2378 supports syntax highlighting and parentheses matching; other editors
2379 include GNU Zile (an Emacs clone), and
2380 nvi (a clone of the original BSD @command{vi} editor).
2381 We strongly recommend storing that file on the target root file system, say,
2382 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2383 configuration file once you have rebooted into the newly-installed system.
2385 @xref{Using the Configuration System}, for an overview of the
2386 configuration file. The example configurations discussed in that
2387 section are available under @file{/etc/configuration} in the
2388 installation image. Thus, to get started with a system configuration
2389 providing a graphical display server (a ``desktop'' system), you can run
2390 something along these lines:
2394 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2395 # nano /mnt/etc/config.scm
2398 You should pay attention to what your configuration file contains, and
2403 Make sure the @code{bootloader-configuration} form refers to the target
2404 you want to install GRUB on. It should mention @code{grub-bootloader} if
2405 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2406 for newer UEFI systems. For legacy systems, the @code{target} field
2407 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2408 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2409 currently mounted and a @code{file-system} entry is specified in your
2413 Be sure that your file system labels match the value of their respective
2414 @code{device} fields in your @code{file-system} configuration, assuming
2415 your @code{file-system} configuration uses the @code{file-system-label}
2416 procedure in its @code{device} field.
2419 If there are encrypted or RAID partitions, make sure to add a
2420 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2423 Once you are done preparing the configuration file, the new system must
2424 be initialized (remember that the target root file system is mounted
2428 guix system init /mnt/etc/config.scm /mnt
2432 This copies all the necessary files and installs GRUB on
2433 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2434 more information, @pxref{Invoking guix system}. This command may trigger
2435 downloads or builds of missing packages, which can take some time.
2437 Once that command has completed---and hopefully succeeded!---you can run
2438 @command{reboot} and boot into the new system. The @code{root} password
2439 in the new system is initially empty; other users' passwords need to be
2440 initialized by running the @command{passwd} command as @code{root},
2441 unless your configuration specifies otherwise
2442 (@pxref{user-account-password, user account passwords}).
2443 @xref{After System Installation}, for what's next!
2446 @node After System Installation
2447 @section After System Installation
2449 Success, you've now booted into Guix System! From then on, you can update the
2450 system whenever you want by running, say:
2454 sudo guix system reconfigure /etc/config.scm
2458 This builds a new system generation with the latest packages and services
2459 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2460 your system includes the latest security updates (@pxref{Security Updates}).
2462 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2464 @cindex sudo vs. @command{guix pull}
2465 Note that @command{sudo guix} runs your user's @command{guix} command and
2466 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2467 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2469 The difference matters here, because @command{guix pull} updates
2470 the @command{guix} command and package definitions only for the user it is ran
2471 as. This means that if you choose to use @command{guix system reconfigure} in
2472 root's login shell, you'll need to @command{guix pull} separately.
2475 Join us on @code{#guix} on the Freenode IRC network or on
2476 @email{guix-devel@@gnu.org} to share your experience!
2479 @node Installing Guix in a VM
2480 @section Installing Guix in a Virtual Machine
2482 @cindex virtual machine, Guix System installation
2483 @cindex virtual private server (VPS)
2484 @cindex VPS (virtual private server)
2485 If you'd like to install Guix System in a virtual machine (VM) or on a
2486 virtual private server (VPS) rather than on your beloved machine, this
2489 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2490 disk image, follow these steps:
2494 First, retrieve and decompress the Guix system installation image as
2495 described previously (@pxref{USB Stick and DVD Installation}).
2498 Create a disk image that will hold the installed system. To make a
2499 qcow2-formatted disk image, use the @command{qemu-img} command:
2502 qemu-img create -f qcow2 guix-system.img 50G
2505 The resulting file will be much smaller than 50 GB (typically less than
2506 1 MB), but it will grow as the virtualized storage device is filled up.
2509 Boot the USB installation image in an VM:
2512 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2513 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2514 -drive file=guix-system.img \
2515 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2518 @code{-enable-kvm} is optional, but significantly improves performance,
2519 @pxref{Running Guix in a VM}.
2522 You're now root in the VM, proceed with the installation process.
2523 @xref{Preparing for Installation}, and follow the instructions.
2526 Once installation is complete, you can boot the system that's on your
2527 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2530 @node Building the Installation Image
2531 @section Building the Installation Image
2533 @cindex installation image
2534 The installation image described above was built using the @command{guix
2535 system} command, specifically:
2538 guix system disk-image --file-system-type=iso9660 \
2539 gnu/system/install.scm
2542 Have a look at @file{gnu/system/install.scm} in the source tree,
2543 and see also @ref{Invoking guix system} for more information
2544 about the installation image.
2546 @section Building the Installation Image for ARM Boards
2548 Many ARM boards require a specific variant of the
2549 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2551 If you build a disk image and the bootloader is not available otherwise
2552 (on another boot drive etc), it's advisable to build an image that
2553 includes the bootloader, specifically:
2556 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2559 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2560 board, a list of possible boards will be printed.
2562 @c *********************************************************************
2563 @node Package Management
2564 @chapter Package Management
2567 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2568 remove software packages, without having to know about their build
2569 procedures or dependencies. Guix also goes beyond this obvious set of
2572 This chapter describes the main features of Guix, as well as the
2573 package management tools it provides. Along with the command-line
2574 interface described below (@pxref{Invoking guix package, @code{guix
2575 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2576 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2577 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2581 guix install emacs-guix
2585 * Features:: How Guix will make your life brighter.
2586 * Invoking guix package:: Package installation, removal, etc.
2587 * Substitutes:: Downloading pre-built binaries.
2588 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2589 * Invoking guix gc:: Running the garbage collector.
2590 * Invoking guix pull:: Fetching the latest Guix and distribution.
2591 * Channels:: Customizing the package collection.
2592 * Invoking guix time-machine:: Running an older revision of Guix.
2593 * Inferiors:: Interacting with another revision of Guix.
2594 * Invoking guix describe:: Display information about your Guix revision.
2595 * Invoking guix archive:: Exporting and importing store files.
2601 When using Guix, each package ends up in the @dfn{package store}, in its
2602 own directory---something that resembles
2603 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2605 Instead of referring to these directories, users have their own
2606 @dfn{profile}, which points to the packages that they actually want to
2607 use. These profiles are stored within each user's home directory, at
2608 @code{$HOME/.guix-profile}.
2610 For example, @code{alice} installs GCC 4.7.2. As a result,
2611 @file{/home/alice/.guix-profile/bin/gcc} points to
2612 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2613 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2614 simply continues to point to
2615 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2616 coexist on the same system without any interference.
2618 The @command{guix package} command is the central tool to manage
2619 packages (@pxref{Invoking guix package}). It operates on the per-user
2620 profiles, and can be used @emph{with normal user privileges}.
2622 @cindex transactions
2623 The command provides the obvious install, remove, and upgrade
2624 operations. Each invocation is actually a @emph{transaction}: either
2625 the specified operation succeeds, or nothing happens. Thus, if the
2626 @command{guix package} process is terminated during the transaction,
2627 or if a power outage occurs during the transaction, then the user's
2628 profile remains in its previous state, and remains usable.
2630 In addition, any package transaction may be @emph{rolled back}. So, if,
2631 for example, an upgrade installs a new version of a package that turns
2632 out to have a serious bug, users may roll back to the previous instance
2633 of their profile, which was known to work well. Similarly, the global
2634 system configuration on Guix is subject to
2635 transactional upgrades and roll-back
2636 (@pxref{Using the Configuration System}).
2638 All packages in the package store may be @emph{garbage-collected}.
2639 Guix can determine which packages are still referenced by user
2640 profiles, and remove those that are provably no longer referenced
2641 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2642 generations of their profile so that the packages they refer to can be
2645 @cindex reproducibility
2646 @cindex reproducible builds
2647 Guix takes a @dfn{purely functional} approach to package
2648 management, as described in the introduction (@pxref{Introduction}).
2649 Each @file{/gnu/store} package directory name contains a hash of all the
2650 inputs that were used to build that package---compiler, libraries, build
2651 scripts, etc. This direct correspondence allows users to make sure a
2652 given package installation matches the current state of their
2653 distribution. It also helps maximize @dfn{build reproducibility}:
2654 thanks to the isolated build environments that are used, a given build
2655 is likely to yield bit-identical files when performed on different
2656 machines (@pxref{Invoking guix-daemon, container}).
2659 This foundation allows Guix to support @dfn{transparent binary/source
2660 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2661 available from an external source---a @dfn{substitute}, Guix just
2662 downloads it and unpacks it;
2663 otherwise, it builds the package from source, locally
2664 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2665 reproducible, users do not have to trust servers that provide
2666 substitutes: they can force a local build and @emph{challenge} providers
2667 (@pxref{Invoking guix challenge}).
2669 Control over the build environment is a feature that is also useful for
2670 developers. The @command{guix environment} command allows developers of
2671 a package to quickly set up the right development environment for their
2672 package, without having to manually install the dependencies of the
2673 package into their profile (@pxref{Invoking guix environment}).
2675 @cindex replication, of software environments
2676 @cindex provenance tracking, of software artifacts
2677 All of Guix and its package definitions is version-controlled, and
2678 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2679 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2680 Guix instance on a different machine or at a later point in time, which in
2681 turn allows you to @emph{replicate complete software environments}, while
2682 retaining precise @dfn{provenance tracking} of the software.
2684 @node Invoking guix package
2685 @section Invoking @command{guix package}
2687 @cindex installing packages
2688 @cindex removing packages
2689 @cindex package installation
2690 @cindex package removal
2691 The @command{guix package} command is the tool that allows users to
2692 install, upgrade, and remove packages, as well as rolling back to
2693 previous configurations. It operates only on the user's own profile,
2694 and works with normal user privileges (@pxref{Features}). Its syntax
2698 guix package @var{options}
2701 @cindex transactions
2702 Primarily, @var{options} specifies the operations to be performed during
2703 the transaction. Upon completion, a new profile is created, but
2704 previous @dfn{generations} of the profile remain available, should the user
2707 For example, to remove @code{lua} and install @code{guile} and
2708 @code{guile-cairo} in a single transaction:
2711 guix package -r lua -i guile guile-cairo
2714 @cindex aliases, for @command{guix package}
2715 For your convenience, we also provide the following aliases:
2719 @command{guix search} is an alias for @command{guix package -s},
2721 @command{guix install} is an alias for @command{guix package -i},
2723 @command{guix remove} is an alias for @command{guix package -r},
2725 @command{guix upgrade} is an alias for @command{guix package -u},
2727 and @command{guix show} is an alias for @command{guix package --show=}.
2730 These aliases are less expressive than @command{guix package} and provide
2731 fewer options, so in some cases you'll probably want to use @command{guix
2734 @command{guix package} also supports a @dfn{declarative approach}
2735 whereby the user specifies the exact set of packages to be available and
2736 passes it @i{via} the @option{--manifest} option
2737 (@pxref{profile-manifest, @option{--manifest}}).
2740 For each user, a symlink to the user's default profile is automatically
2741 created in @file{$HOME/.guix-profile}. This symlink always points to the
2742 current generation of the user's default profile. Thus, users can add
2743 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
2744 variable, and so on.
2745 @cindex search paths
2746 If you are not using Guix System, consider adding the
2747 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2748 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2749 shells get all the right environment variable definitions:
2752 GUIX_PROFILE="$HOME/.guix-profile" ; \
2753 source "$HOME/.guix-profile/etc/profile"
2756 In a multi-user setup, user profiles are stored in a place registered as
2757 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2758 to (@pxref{Invoking guix gc}). That directory is normally
2759 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2760 @var{localstatedir} is the value passed to @code{configure} as
2761 @option{--localstatedir}, and @var{user} is the user name. The
2762 @file{per-user} directory is created when @command{guix-daemon} is
2763 started, and the @var{user} sub-directory is created by @command{guix
2766 The @var{options} can be among the following:
2770 @item --install=@var{package} @dots{}
2771 @itemx -i @var{package} @dots{}
2772 Install the specified @var{package}s.
2774 Each @var{package} may specify either a simple package name, such as
2775 @code{guile}, or a package name followed by an at-sign and version number,
2776 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2777 case, the newest version prefixed by @code{1.8} is selected).
2779 If no version number is specified, the
2780 newest available version will be selected. In addition, @var{package}
2781 may contain a colon, followed by the name of one of the outputs of the
2782 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2783 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2784 name (and optionally version) are searched for among the GNU
2785 distribution modules (@pxref{Package Modules}).
2787 @cindex propagated inputs
2788 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2789 that automatically get installed along with the required package
2790 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2791 @code{package} objects}, for information about propagated inputs in
2792 package definitions).
2794 @anchor{package-cmd-propagated-inputs}
2795 An example is the GNU MPC library: its C header files refer to those of
2796 the GNU MPFR library, which in turn refer to those of the GMP library.
2797 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2798 in the profile; removing MPC also removes MPFR and GMP---unless they had
2799 also been explicitly installed by the user.
2801 Besides, packages sometimes rely on the definition of environment
2802 variables for their search paths (see explanation of
2803 @option{--search-paths} below). Any missing or possibly incorrect
2804 environment variable definitions are reported here.
2806 @item --install-from-expression=@var{exp}
2808 Install the package @var{exp} evaluates to.
2810 @var{exp} must be a Scheme expression that evaluates to a
2811 @code{<package>} object. This option is notably useful to disambiguate
2812 between same-named variants of a package, with expressions such as
2813 @code{(@@ (gnu packages base) guile-final)}.
2815 Note that this option installs the first output of the specified
2816 package, which may be insufficient when needing a specific output of a
2817 multiple-output package.
2819 @item --install-from-file=@var{file}
2820 @itemx -f @var{file}
2821 Install the package that the code within @var{file} evaluates to.
2823 As an example, @var{file} might contain a definition like this
2824 (@pxref{Defining Packages}):
2827 @include package-hello.scm
2830 Developers may find it useful to include such a @file{guix.scm} file
2831 in the root of their project source tree that can be used to test
2832 development snapshots and create reproducible development environments
2833 (@pxref{Invoking guix environment}).
2835 The @var{file} may also contain a JSON representation of one or more
2836 package definitions. Running @code{guix package -f} on
2837 @file{hello.json} with the following contents would result in installing
2838 the package @code{greeter} after building @code{myhello}:
2841 @verbatiminclude package-hello.json
2844 @item --remove=@var{package} @dots{}
2845 @itemx -r @var{package} @dots{}
2846 Remove the specified @var{package}s.
2848 As for @option{--install}, each @var{package} may specify a version number
2849 and/or output name in addition to the package name. For instance,
2850 @samp{-r glibc:debug} would remove the @code{debug} output of
2853 @item --upgrade[=@var{regexp} @dots{}]
2854 @itemx -u [@var{regexp} @dots{}]
2855 @cindex upgrading packages
2856 Upgrade all the installed packages. If one or more @var{regexp}s are
2857 specified, upgrade only installed packages whose name matches a
2858 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
2860 Note that this upgrades package to the latest version of packages found
2861 in the distribution currently installed. To update your distribution,
2862 you should regularly run @command{guix pull} (@pxref{Invoking guix
2865 @item --do-not-upgrade[=@var{regexp} @dots{}]
2866 When used together with the @option{--upgrade} option, do @emph{not}
2867 upgrade any packages whose name matches a @var{regexp}. For example, to
2868 upgrade all packages in the current profile except those containing the
2869 substring ``emacs'':
2872 $ guix package --upgrade . --do-not-upgrade emacs
2875 @item @anchor{profile-manifest}--manifest=@var{file}
2876 @itemx -m @var{file}
2877 @cindex profile declaration
2878 @cindex profile manifest
2879 Create a new generation of the profile from the manifest object
2880 returned by the Scheme code in @var{file}. This option can be repeated
2881 several times, in which case the manifests are concatenated.
2883 This allows you to @emph{declare} the profile's contents rather than
2884 constructing it through a sequence of @option{--install} and similar
2885 commands. The advantage is that @var{file} can be put under version
2886 control, copied to different machines to reproduce the same profile, and
2889 @c FIXME: Add reference to (guix profile) documentation when available.
2890 @var{file} must return a @dfn{manifest} object, which is roughly a list
2893 @findex packages->manifest
2895 (use-package-modules guile emacs)
2900 ;; Use a specific package output.
2901 (list guile-2.0 "debug")))
2904 @findex specifications->manifest
2905 In this example we have to know which modules define the @code{emacs}
2906 and @code{guile-2.0} variables to provide the right
2907 @code{use-package-modules} line, which can be cumbersome. We can
2908 instead provide regular package specifications and let
2909 @code{specifications->manifest} look up the corresponding package
2913 (specifications->manifest
2914 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2918 @cindex rolling back
2919 @cindex undoing transactions
2920 @cindex transactions, undoing
2921 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2922 the last transaction.
2924 When combined with options such as @option{--install}, roll back occurs
2925 before any other actions.
2927 When rolling back from the first generation that actually contains
2928 installed packages, the profile is made to point to the @dfn{zeroth
2929 generation}, which contains no files apart from its own metadata.
2931 After having rolled back, installing, removing, or upgrading packages
2932 overwrites previous future generations. Thus, the history of the
2933 generations in a profile is always linear.
2935 @item --switch-generation=@var{pattern}
2936 @itemx -S @var{pattern}
2938 Switch to a particular generation defined by @var{pattern}.
2940 @var{pattern} may be either a generation number or a number prefixed
2941 with ``+'' or ``-''. The latter means: move forward/backward by a
2942 specified number of generations. For example, if you want to return to
2943 the latest generation after @option{--roll-back}, use
2944 @option{--switch-generation=+1}.
2946 The difference between @option{--roll-back} and
2947 @option{--switch-generation=-1} is that @option{--switch-generation} will
2948 not make a zeroth generation, so if a specified generation does not
2949 exist, the current generation will not be changed.
2951 @item --search-paths[=@var{kind}]
2952 @cindex search paths
2953 Report environment variable definitions, in Bash syntax, that may be
2954 needed in order to use the set of installed packages. These environment
2955 variables are used to specify @dfn{search paths} for files used by some
2956 of the installed packages.
2958 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
2959 environment variables to be defined so it can look for headers and
2960 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2961 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2962 library are installed in the profile, then @option{--search-paths} will
2963 suggest setting these variables to @file{@var{profile}/include} and
2964 @file{@var{profile}/lib}, respectively.
2966 The typical use case is to define these environment variables in the
2970 $ eval `guix package --search-paths`
2973 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2974 meaning that the returned environment variable definitions will either
2975 be exact settings, or prefixes or suffixes of the current value of these
2976 variables. When omitted, @var{kind} defaults to @code{exact}.
2978 This option can also be used to compute the @emph{combined} search paths
2979 of several profiles. Consider this example:
2982 $ guix package -p foo -i guile
2983 $ guix package -p bar -i guile-json
2984 $ guix package -p foo -p bar --search-paths
2987 The last command above reports about the @env{GUILE_LOAD_PATH}
2988 variable, even though, taken individually, neither @file{foo} nor
2989 @file{bar} would lead to that recommendation.
2992 @item --profile=@var{profile}
2993 @itemx -p @var{profile}
2994 Use @var{profile} instead of the user's default profile.
2996 @var{profile} must be the name of a file that will be created upon
2997 completion. Concretely, @var{profile} will be a mere symbolic link
2998 (``symlink'') pointing to the actual profile where packages are
3002 $ guix install hello -p ~/code/my-profile
3004 $ ~/code/my-profile/bin/hello
3008 All it takes to get rid of the profile is to remove this symlink and its
3009 siblings that point to specific generations:
3012 $ rm ~/code/my-profile ~/code/my-profile-*-link
3015 @item --list-profiles
3016 List all the user's profiles:
3019 $ guix package --list-profiles
3020 /home/charlie/.guix-profile
3021 /home/charlie/code/my-profile
3022 /home/charlie/code/devel-profile
3023 /home/charlie/tmp/test
3026 When running as root, list all the profiles of all the users.
3028 @cindex collisions, in a profile
3029 @cindex colliding packages in profiles
3030 @cindex profile collisions
3031 @item --allow-collisions
3032 Allow colliding packages in the new profile. Use at your own risk!
3034 By default, @command{guix package} reports as an error @dfn{collisions}
3035 in the profile. Collisions happen when two or more different versions
3036 or variants of a given package end up in the profile.
3039 Use the bootstrap Guile to build the profile. This option is only
3040 useful to distribution developers.
3044 In addition to these actions, @command{guix package} supports the
3045 following options to query the current state of a profile, or the
3046 availability of packages:
3050 @item --search=@var{regexp}
3051 @itemx -s @var{regexp}
3052 @anchor{guix-search}
3053 @cindex searching for packages
3054 List the available packages whose name, synopsis, or description matches
3055 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3056 Print all the metadata of matching packages in
3057 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3058 GNU recutils manual}).
3060 This allows specific fields to be extracted using the @command{recsel}
3061 command, for instance:
3064 $ guix package -s malloc | recsel -p name,version,relevance
3078 Similarly, to show the name of all the packages available under the
3079 terms of the GNU@tie{}LGPL version 3:
3082 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3089 It is also possible to refine search results using several @code{-s} flags to
3090 @command{guix package}, or several arguments to @command{guix search}. For
3091 example, the following command returns a list of board games (this time using
3092 the @command{guix search} alias):
3095 $ guix search '\<board\>' game | recsel -p name
3100 If we were to omit @code{-s game}, we would also get software packages
3101 that deal with printed circuit boards; removing the angle brackets
3102 around @code{board} would further add packages that have to do with
3105 And now for a more elaborate example. The following command searches
3106 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3107 libraries, and prints the name and synopsis of the matching packages:
3110 $ guix search crypto library | \
3111 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3115 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3116 information on @dfn{selection expressions} for @code{recsel -e}.
3118 @item --show=@var{package}
3119 Show details about @var{package}, taken from the list of available packages, in
3120 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3124 $ guix package --show=python | recsel -p name,version
3132 You may also specify the full name of a package to only get details about a
3133 specific version of it (this time using the @command{guix show} alias):
3135 $ guix show python@@3.4 | recsel -p name,version
3142 @item --list-installed[=@var{regexp}]
3143 @itemx -I [@var{regexp}]
3144 List the currently installed packages in the specified profile, with the
3145 most recently installed packages shown last. When @var{regexp} is
3146 specified, list only installed packages whose name matches @var{regexp}.
3148 For each installed package, print the following items, separated by
3149 tabs: the package name, its version string, the part of the package that
3150 is installed (for instance, @code{out} for the default output,
3151 @code{include} for its headers, etc.), and the path of this package in
3154 @item --list-available[=@var{regexp}]
3155 @itemx -A [@var{regexp}]
3156 List packages currently available in the distribution for this system
3157 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3158 available packages whose name matches @var{regexp}.
3160 For each package, print the following items separated by tabs: its name,
3161 its version string, the parts of the package (@pxref{Packages with
3162 Multiple Outputs}), and the source location of its definition.
3164 @item --list-generations[=@var{pattern}]
3165 @itemx -l [@var{pattern}]
3167 Return a list of generations along with their creation dates; for each
3168 generation, show the installed packages, with the most recently
3169 installed packages shown last. Note that the zeroth generation is never
3172 For each installed package, print the following items, separated by
3173 tabs: the name of a package, its version string, the part of the package
3174 that is installed (@pxref{Packages with Multiple Outputs}), and the
3175 location of this package in the store.
3177 When @var{pattern} is used, the command returns only matching
3178 generations. Valid patterns include:
3181 @item @emph{Integers and comma-separated integers}. Both patterns denote
3182 generation numbers. For instance, @option{--list-generations=1} returns
3185 And @option{--list-generations=1,8,2} outputs three generations in the
3186 specified order. Neither spaces nor trailing commas are allowed.
3188 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3189 specified generations and everything in between. Note that the start of
3190 a range must be smaller than its end.
3192 It is also possible to omit the endpoint. For example,
3193 @option{--list-generations=2..}, returns all generations starting from the
3196 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3197 or months by passing an integer along with the first letter of the
3198 duration. For example, @option{--list-generations=20d} lists generations
3199 that are up to 20 days old.
3202 @item --delete-generations[=@var{pattern}]
3203 @itemx -d [@var{pattern}]
3204 When @var{pattern} is omitted, delete all generations except the current
3207 This command accepts the same patterns as @option{--list-generations}.
3208 When @var{pattern} is specified, delete the matching generations. When
3209 @var{pattern} specifies a duration, generations @emph{older} than the
3210 specified duration match. For instance, @option{--delete-generations=1m}
3211 deletes generations that are more than one month old.
3213 If the current generation matches, it is @emph{not} deleted. Also, the
3214 zeroth generation is never deleted.
3216 Note that deleting generations prevents rolling back to them.
3217 Consequently, this command must be used with care.
3221 Finally, since @command{guix package} may actually start build
3222 processes, it supports all the common build options (@pxref{Common Build
3223 Options}). It also supports package transformation options, such as
3224 @option{--with-source} (@pxref{Package Transformation Options}).
3225 However, note that package transformations are lost when upgrading; to
3226 preserve transformations across upgrades, you should define your own
3227 package variant in a Guile module and add it to @env{GUIX_PACKAGE_PATH}
3228 (@pxref{Defining Packages}).
3231 @section Substitutes
3234 @cindex pre-built binaries
3235 Guix supports transparent source/binary deployment, which means that it
3236 can either build things locally, or download pre-built items from a
3237 server, or both. We call these pre-built items @dfn{substitutes}---they
3238 are substitutes for local build results. In many cases, downloading a
3239 substitute is much faster than building things locally.
3241 Substitutes can be anything resulting from a derivation build
3242 (@pxref{Derivations}). Of course, in the common case, they are
3243 pre-built package binaries, but source tarballs, for instance, which
3244 also result from derivation builds, can be available as substitutes.
3247 * Official Substitute Server:: One particular source of substitutes.
3248 * Substitute Server Authorization:: How to enable or disable substitutes.
3249 * Substitute Authentication:: How Guix verifies substitutes.
3250 * Proxy Settings:: How to get substitutes via proxy.
3251 * Substitution Failure:: What happens when substitution fails.
3252 * On Trusting Binaries:: How can you trust that binary blob?
3255 @node Official Substitute Server
3256 @subsection Official Substitute Server
3259 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3260 that builds packages from Guix continuously for some
3261 architectures, and makes them available as substitutes. This is the
3262 default source of substitutes; it can be overridden by passing the
3263 @option{--substitute-urls} option either to @command{guix-daemon}
3264 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3265 or to client tools such as @command{guix package}
3266 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3269 Substitute URLs can be either HTTP or HTTPS.
3270 HTTPS is recommended because communications are encrypted; conversely,
3271 using HTTP makes all communications visible to an eavesdropper, who
3272 could use the information gathered to determine, for instance, whether
3273 your system has unpatched security vulnerabilities.
3275 Substitutes from the official build farm are enabled by default when
3276 using Guix System (@pxref{GNU Distribution}). However,
3277 they are disabled by default when using Guix on a foreign distribution,
3278 unless you have explicitly enabled them via one of the recommended
3279 installation steps (@pxref{Installation}). The following paragraphs
3280 describe how to enable or disable substitutes for the official build
3281 farm; the same procedure can also be used to enable substitutes for any
3282 other substitute server.
3284 @node Substitute Server Authorization
3285 @subsection Substitute Server Authorization
3288 @cindex substitutes, authorization thereof
3289 @cindex access control list (ACL), for substitutes
3290 @cindex ACL (access control list), for substitutes
3291 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3293 must add its public key to the access control list (ACL) of archive
3294 imports, using the @command{guix archive} command (@pxref{Invoking guix
3295 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3296 be compromised and to serve genuine substitutes.
3298 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3299 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3300 the installation prefix of Guix. If you installed Guix from source,
3301 make sure you checked the GPG signature of
3302 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3303 Then, you can run something like this:
3306 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3309 Once this is in place, the output of a command like @code{guix build}
3310 should change from something like:
3313 $ guix build emacs --dry-run
3314 The following derivations would be built:
3315 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3316 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3317 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3318 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3326 $ guix build emacs --dry-run
3327 112.3 MB would be downloaded:
3328 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3329 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3330 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3331 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3336 The text changed from ``The following derivations would be built'' to
3337 ``112.3 MB would be downloaded''. This indicates that substitutes from
3338 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3339 possible, for future builds.
3341 @cindex substitutes, how to disable
3342 The substitute mechanism can be disabled globally by running
3343 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
3344 guix-daemon}). It can also be disabled temporarily by passing the
3345 @option{--no-substitutes} option to @command{guix package},
3346 @command{guix build}, and other command-line tools.
3348 @node Substitute Authentication
3349 @subsection Substitute Authentication
3351 @cindex digital signatures
3352 Guix detects and raises an error when attempting to use a substitute
3353 that has been tampered with. Likewise, it ignores substitutes that are
3354 not signed, or that are not signed by one of the keys listed in the ACL.
3356 There is one exception though: if an unauthorized server provides
3357 substitutes that are @emph{bit-for-bit identical} to those provided by
3358 an authorized server, then the unauthorized server becomes eligible for
3359 downloads. For example, assume we have chosen two substitute servers
3363 --substitute-urls="https://a.example.org https://b.example.org"
3367 @cindex reproducible builds
3368 If the ACL contains only the key for @samp{b.example.org}, and if
3369 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
3370 then Guix will download substitutes from @samp{a.example.org} because it
3371 comes first in the list and can be considered a mirror of
3372 @samp{b.example.org}. In practice, independent build machines usually
3373 produce the same binaries, thanks to bit-reproducible builds (see
3376 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3377 (in other words, the server is not authenticated), contrary to what
3378 HTTPS clients such as Web browsers usually do. This is because Guix
3379 authenticates substitute information itself, as explained above, which
3380 is what we care about (whereas X.509 certificates are about
3381 authenticating bindings between domain names and public keys).
3383 @node Proxy Settings
3384 @subsection Proxy Settings
3388 Substitutes are downloaded over HTTP or HTTPS. The @env{http_proxy} and
3389 @env{https_proxy} environment variables can be set in the environment of
3390 @command{guix-daemon} and are honored for downloads of substitutes.
3391 Note that the value of those environment variables in the environment
3392 where @command{guix build}, @command{guix package}, and other client
3393 commands are run has @emph{absolutely no effect}.
3395 @node Substitution Failure
3396 @subsection Substitution Failure
3398 Even when a substitute for a derivation is available, sometimes the
3399 substitution attempt will fail. This can happen for a variety of
3400 reasons: the substitute server might be offline, the substitute may
3401 recently have been deleted, the connection might have been interrupted,
3404 When substitutes are enabled and a substitute for a derivation is
3405 available, but the substitution attempt fails, Guix will attempt to
3406 build the derivation locally depending on whether or not
3407 @option{--fallback} was given (@pxref{fallback-option,, common build
3408 option @option{--fallback}}). Specifically, if @option{--fallback} was
3409 omitted, then no local build will be performed, and the derivation is
3410 considered to have failed. However, if @option{--fallback} was given,
3411 then Guix will attempt to build the derivation locally, and the success
3412 or failure of the derivation depends on the success or failure of the
3413 local build. Note that when substitutes are disabled or no substitute
3414 is available for the derivation in question, a local build will
3415 @emph{always} be performed, regardless of whether or not
3416 @option{--fallback} was given.
3418 To get an idea of how many substitutes are available right now, you can
3419 try running the @command{guix weather} command (@pxref{Invoking guix
3420 weather}). This command provides statistics on the substitutes provided
3423 @node On Trusting Binaries
3424 @subsection On Trusting Binaries
3426 @cindex trust, of pre-built binaries
3427 Today, each individual's control over their own computing is at the
3428 mercy of institutions, corporations, and groups with enough power and
3429 determination to subvert the computing infrastructure and exploit its
3430 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3431 convenient, we encourage users to also build on their own, or even run
3432 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3433 interesting target. One way to help is by publishing the software you
3434 build using @command{guix publish} so that others have one more choice
3435 of server to download substitutes from (@pxref{Invoking guix publish}).
3437 Guix has the foundations to maximize build reproducibility
3438 (@pxref{Features}). In most cases, independent builds of a given
3439 package or derivation should yield bit-identical results. Thus, through
3440 a diverse set of independent package builds, we can strengthen the
3441 integrity of our systems. The @command{guix challenge} command aims to
3442 help users assess substitute servers, and to assist developers in
3443 finding out about non-deterministic package builds (@pxref{Invoking guix
3444 challenge}). Similarly, the @option{--check} option of @command{guix
3445 build} allows users to check whether previously-installed substitutes
3446 are genuine by rebuilding them locally (@pxref{build-check,
3447 @command{guix build --check}}).
3449 In the future, we want Guix to have support to publish and retrieve
3450 binaries to/from other users, in a peer-to-peer fashion. If you would
3451 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3453 @node Packages with Multiple Outputs
3454 @section Packages with Multiple Outputs
3456 @cindex multiple-output packages
3457 @cindex package outputs
3460 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3461 source package leads to exactly one directory in the store. When running
3462 @command{guix install glibc}, one installs the default output of the
3463 GNU libc package; the default output is called @code{out}, but its name
3464 can be omitted as shown in this command. In this particular case, the
3465 default output of @code{glibc} contains all the C header files, shared
3466 libraries, static libraries, Info documentation, and other supporting
3469 Sometimes it is more appropriate to separate the various types of files
3470 produced from a single source package into separate outputs. For
3471 instance, the GLib C library (used by GTK+ and related packages)
3472 installs more than 20 MiB of reference documentation as HTML pages.
3473 To save space for users who do not need it, the documentation goes to a
3474 separate output, called @code{doc}. To install the main GLib output,
3475 which contains everything but the documentation, one would run:
3481 @cindex documentation
3482 The command to install its documentation is:
3485 guix install glib:doc
3488 Some packages install programs with different ``dependency footprints''.
3489 For instance, the WordNet package installs both command-line tools and
3490 graphical user interfaces (GUIs). The former depend solely on the C
3491 library, whereas the latter depend on Tcl/Tk and the underlying X
3492 libraries. In this case, we leave the command-line tools in the default
3493 output, whereas the GUIs are in a separate output. This allows users
3494 who do not need the GUIs to save space. The @command{guix size} command
3495 can help find out about such situations (@pxref{Invoking guix size}).
3496 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3498 There are several such multiple-output packages in the GNU distribution.
3499 Other conventional output names include @code{lib} for libraries and
3500 possibly header files, @code{bin} for stand-alone programs, and
3501 @code{debug} for debugging information (@pxref{Installing Debugging
3502 Files}). The outputs of a packages are listed in the third column of
3503 the output of @command{guix package --list-available} (@pxref{Invoking
3507 @node Invoking guix gc
3508 @section Invoking @command{guix gc}
3510 @cindex garbage collector
3512 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3513 The @command{guix gc} command allows users to explicitly run the garbage
3514 collector to reclaim space from the @file{/gnu/store} directory. It is
3515 the @emph{only} way to remove files from @file{/gnu/store}---removing
3516 files or directories manually may break it beyond repair!
3519 @cindex garbage collector roots
3520 The garbage collector has a set of known @dfn{roots}: any file under
3521 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3522 cannot be deleted; any other file is considered @dfn{dead} and may be
3523 deleted. The set of garbage collector roots (``GC roots'' for short)
3524 includes default user profiles; by default, the symlinks under
3525 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3526 added with @command{guix build --root}, for example (@pxref{Invoking
3527 guix build}). The @command{guix gc --list-roots} command lists them.
3529 Prior to running @code{guix gc --collect-garbage} to make space, it is
3530 often useful to remove old generations from user profiles; that way, old
3531 package builds referenced by those generations can be reclaimed. This
3532 is achieved by running @code{guix package --delete-generations}
3533 (@pxref{Invoking guix package}).
3535 Our recommendation is to run a garbage collection periodically, or when
3536 you are short on disk space. For instance, to guarantee that at least
3537 5@tie{}GB are available on your disk, simply run:
3543 It is perfectly safe to run as a non-interactive periodic job
3544 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3545 Running @command{guix gc} with no arguments will collect as
3546 much garbage as it can, but that is often inconvenient: you may find
3547 yourself having to rebuild or re-download software that is ``dead'' from
3548 the GC viewpoint but that is necessary to build other pieces of
3549 software---e.g., the compiler tool chain.
3551 The @command{guix gc} command has three modes of operation: it can be
3552 used to garbage-collect any dead files (the default), to delete specific
3553 files (the @option{--delete} option), to print garbage-collector
3554 information, or for more advanced queries. The garbage collection
3555 options are as follows:
3558 @item --collect-garbage[=@var{min}]
3559 @itemx -C [@var{min}]
3560 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3561 sub-directories. This is the default operation when no option is
3564 When @var{min} is given, stop once @var{min} bytes have been collected.
3565 @var{min} may be a number of bytes, or it may include a unit as a
3566 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3567 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3569 When @var{min} is omitted, collect all the garbage.
3571 @item --free-space=@var{free}
3572 @itemx -F @var{free}
3573 Collect garbage until @var{free} space is available under
3574 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3575 as @code{500MiB}, as described above.
3577 When @var{free} or more is already available in @file{/gnu/store}, do
3578 nothing and exit immediately.
3580 @item --delete-generations[=@var{duration}]
3581 @itemx -d [@var{duration}]
3582 Before starting the garbage collection process, delete all the generations
3583 older than @var{duration}, for all the user profiles; when run as root, this
3584 applies to all the profiles @emph{of all the users}.
3586 For example, this command deletes all the generations of all your profiles
3587 that are older than 2 months (except generations that are current), and then
3588 proceeds to free space until at least 10 GiB are available:
3591 guix gc -d 2m -F 10G
3596 Attempt to delete all the store files and directories specified as
3597 arguments. This fails if some of the files are not in the store, or if
3598 they are still live.
3600 @item --list-failures
3601 List store items corresponding to cached build failures.
3603 This prints nothing unless the daemon was started with
3604 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3605 @option{--cache-failures}}).
3608 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3612 List store items in use by currently running processes. These store
3613 items are effectively considered GC roots: they cannot be deleted.
3615 @item --clear-failures
3616 Remove the specified store items from the failed-build cache.
3618 Again, this option only makes sense when the daemon is started with
3619 @option{--cache-failures}. Otherwise, it does nothing.
3622 Show the list of dead files and directories still present in the
3623 store---i.e., files and directories no longer reachable from any root.
3626 Show the list of live store files and directories.
3630 In addition, the references among existing store files can be queried:
3636 @cindex package dependencies
3637 List the references (respectively, the referrers) of store files given
3643 List the requisites of the store files passed as arguments. Requisites
3644 include the store files themselves, their references, and the references
3645 of these, recursively. In other words, the returned list is the
3646 @dfn{transitive closure} of the store files.
3648 @xref{Invoking guix size}, for a tool to profile the size of the closure
3649 of an element. @xref{Invoking guix graph}, for a tool to visualize
3650 the graph of references.
3654 Return the derivation(s) leading to the given store items
3655 (@pxref{Derivations}).
3657 For example, this command:
3660 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3664 returns the @file{.drv} file(s) leading to the @code{emacs} package
3665 installed in your profile.
3667 Note that there may be zero matching @file{.drv} files, for instance
3668 because these files have been garbage-collected. There can also be more
3669 than one matching @file{.drv} due to fixed-output derivations.
3672 Lastly, the following options allow you to check the integrity of the
3673 store and to control disk usage.
3677 @item --verify[=@var{options}]
3678 @cindex integrity, of the store
3679 @cindex integrity checking
3680 Verify the integrity of the store.
3682 By default, make sure that all the store items marked as valid in the
3683 database of the daemon actually exist in @file{/gnu/store}.
3685 When provided, @var{options} must be a comma-separated list containing one
3686 or more of @code{contents} and @code{repair}.
3688 When passing @option{--verify=contents}, the daemon computes the
3689 content hash of each store item and compares it against its hash in the
3690 database. Hash mismatches are reported as data corruptions. Because it
3691 traverses @emph{all the files in the store}, this command can take a
3692 long time, especially on systems with a slow disk drive.
3694 @cindex repairing the store
3695 @cindex corruption, recovering from
3696 Using @option{--verify=repair} or @option{--verify=contents,repair}
3697 causes the daemon to try to repair corrupt store items by fetching
3698 substitutes for them (@pxref{Substitutes}). Because repairing is not
3699 atomic, and thus potentially dangerous, it is available only to the
3700 system administrator. A lightweight alternative, when you know exactly
3701 which items in the store are corrupt, is @command{guix build --repair}
3702 (@pxref{Invoking guix build}).
3705 @cindex deduplication
3706 Optimize the store by hard-linking identical files---this is
3707 @dfn{deduplication}.
3709 The daemon performs deduplication after each successful build or archive
3710 import, unless it was started with @option{--disable-deduplication}
3711 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
3712 this option is primarily useful when the daemon was running with
3713 @option{--disable-deduplication}.
3717 @node Invoking guix pull
3718 @section Invoking @command{guix pull}
3720 @cindex upgrading Guix
3721 @cindex updating Guix
3722 @cindex @command{guix pull}
3724 Packages are installed or upgraded to the latest version available in
3725 the distribution currently available on your local machine. To update
3726 that distribution, along with the Guix tools, you must run @command{guix
3727 pull}: the command downloads the latest Guix source code and package
3728 descriptions, and deploys it. Source code is downloaded from a
3729 @uref{https://git-scm.com, Git} repository, by default the official
3730 GNU@tie{}Guix repository, though this can be customized.
3732 Specifically, @command{guix pull} downloads code from the @dfn{channels}
3733 (@pxref{Channels}) specified by one of the followings, in this order:
3737 the @option{--channels} option;
3739 the user's @file{~/.config/guix/channels.scm} file;
3741 the system-wide @file{/etc/guix/channels.scm} file;
3743 the built-in default channels specified in the @code{%default-channels}
3747 On completion, @command{guix package} will use packages and package
3748 versions from this just-retrieved copy of Guix. Not only that, but all
3749 the Guix commands and Scheme modules will also be taken from that latest
3750 version. New @command{guix} sub-commands added by the update also
3753 Any user can update their Guix copy using @command{guix pull}, and the
3754 effect is limited to the user who ran @command{guix pull}. For
3755 instance, when user @code{root} runs @command{guix pull}, this has no
3756 effect on the version of Guix that user @code{alice} sees, and vice
3759 The result of running @command{guix pull} is a @dfn{profile} available
3760 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3761 make sure to add it to the beginning of your search path so that you use
3762 the latest version, and similarly for the Info manual
3763 (@pxref{Documentation}):
3766 export PATH="$HOME/.config/guix/current/bin:$PATH"
3767 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3770 The @option{--list-generations} or @option{-l} option lists past generations
3771 produced by @command{guix pull}, along with details about their provenance:
3775 Generation 1 Jun 10 2018 00:18:18
3777 repository URL: https://git.savannah.gnu.org/git/guix.git
3778 branch: origin/master
3779 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3781 Generation 2 Jun 11 2018 11:02:49
3783 repository URL: https://git.savannah.gnu.org/git/guix.git
3784 branch: origin/master
3785 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3786 2 new packages: keepalived, libnfnetlink
3787 6 packages upgraded: emacs-nix-mode@@2.0.4,
3788 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3789 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3791 Generation 3 Jun 13 2018 23:31:07 (current)
3793 repository URL: https://git.savannah.gnu.org/git/guix.git
3794 branch: origin/master
3795 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3796 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3797 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3800 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3801 describe the current status of Guix.
3803 This @code{~/.config/guix/current} profile works exactly like the profiles
3804 created by @command{guix package} (@pxref{Invoking guix package}). That
3805 is, you can list generations, roll back to the previous
3806 generation---i.e., the previous Guix---and so on:
3809 $ guix pull --roll-back
3810 switched from generation 3 to 2
3811 $ guix pull --delete-generations=1
3812 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3815 You can also use @command{guix package} (@pxref{Invoking guix package})
3816 to manage the profile by naming it explicitly:
3818 $ guix package -p ~/.config/guix/current --roll-back
3819 switched from generation 3 to 2
3820 $ guix package -p ~/.config/guix/current --delete-generations=1
3821 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3824 The @command{guix pull} command is usually invoked with no arguments,
3825 but it supports the following options:
3828 @item --url=@var{url}
3829 @itemx --commit=@var{commit}
3830 @itemx --branch=@var{branch}
3831 Download code for the @code{guix} channel from the specified @var{url}, at the
3832 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3833 string), or @var{branch}.
3835 @cindex @file{channels.scm}, configuration file
3836 @cindex configuration file for channels
3837 These options are provided for convenience, but you can also specify your
3838 configuration in the @file{~/.config/guix/channels.scm} file or using the
3839 @option{--channels} option (see below).
3841 @item --channels=@var{file}
3842 @itemx -C @var{file}
3843 Read the list of channels from @var{file} instead of
3844 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
3845 @var{file} must contain Scheme code that
3846 evaluates to a list of channel objects. @xref{Channels}, for more
3849 @cindex channel news
3852 Display the list of packages added or upgraded since the previous
3853 generation, as well as, occasionally, news written by channel authors
3854 for their users (@pxref{Channels, Writing Channel News}).
3856 The package information is the same as displayed upon @command{guix
3857 pull} completion, but without ellipses; it is also similar to the output
3858 of @command{guix pull -l} for the last generation (see below).
3860 @item --list-generations[=@var{pattern}]
3861 @itemx -l [@var{pattern}]
3862 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3863 is provided, the subset of generations that match @var{pattern}.
3864 The syntax of @var{pattern} is the same as with @code{guix package
3865 --list-generations} (@pxref{Invoking guix package}).
3868 @cindex rolling back
3869 @cindex undoing transactions
3870 @cindex transactions, undoing
3871 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
3872 undo the last transaction.
3874 @item --switch-generation=@var{pattern}
3875 @itemx -S @var{pattern}
3877 Switch to a particular generation defined by @var{pattern}.
3879 @var{pattern} may be either a generation number or a number prefixed
3880 with ``+'' or ``-''. The latter means: move forward/backward by a
3881 specified number of generations. For example, if you want to return to
3882 the latest generation after @option{--roll-back}, use
3883 @option{--switch-generation=+1}.
3885 @item --delete-generations[=@var{pattern}]
3886 @itemx -d [@var{pattern}]
3887 When @var{pattern} is omitted, delete all generations except the current
3890 This command accepts the same patterns as @option{--list-generations}.
3891 When @var{pattern} is specified, delete the matching generations. When
3892 @var{pattern} specifies a duration, generations @emph{older} than the
3893 specified duration match. For instance, @option{--delete-generations=1m}
3894 deletes generations that are more than one month old.
3896 If the current generation matches, it is @emph{not} deleted.
3898 Note that deleting generations prevents rolling back to them.
3899 Consequently, this command must be used with care.
3901 @xref{Invoking guix describe}, for a way to display information about the
3902 current generation only.
3904 @item --profile=@var{profile}
3905 @itemx -p @var{profile}
3906 Use @var{profile} instead of @file{~/.config/guix/current}.
3910 Show which channel commit(s) would be used and what would be built or
3911 substituted but do not actually do it.
3913 @item --allow-downgrades
3914 Allow pulling older or unrelated revisions of channels than those
3917 @cindex downgrade attacks, protection against
3918 By default, @command{guix pull} protects against so-called ``downgrade
3919 attacks'' whereby the Git repository of a channel would be reset to an
3920 earlier or unrelated revision of itself, potentially leading you to
3921 install older, known-vulnerable versions of software packages.
3924 Make sure you understand its security implications before using
3925 @option{--allow-downgrades}.
3928 @item --system=@var{system}
3929 @itemx -s @var{system}
3930 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3931 the system type of the build host.
3934 Produce verbose output, writing build logs to the standard error output.
3937 Use the bootstrap Guile to build the latest Guix. This option is only
3938 useful to Guix developers.
3941 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3942 repository and branch to pull from, as well as @emph{additional} repositories
3943 containing package modules that should be deployed. @xref{Channels}, for more
3946 In addition, @command{guix pull} supports all the common build options
3947 (@pxref{Common Build Options}).
3953 @cindex @file{channels.scm}, configuration file
3954 @cindex configuration file for channels
3955 @cindex @command{guix pull}, configuration file
3956 @cindex configuration of @command{guix pull}
3957 Guix and its package collection are updated by running @command{guix pull}
3958 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3959 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3960 customized by defining @dfn{channels} in the
3961 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3962 of a Git repository to be deployed, and @command{guix pull} can be instructed
3963 to pull from one or more channels. In other words, channels can be used to
3964 @emph{customize} and to @emph{extend} Guix, as we will see below.
3966 @subsection Using a Custom Guix Channel
3968 The channel called @code{guix} specifies where Guix itself---its command-line
3969 tools as well as its package collection---should be downloaded. For instance,
3970 suppose you want to update from your own copy of the Guix repository at
3971 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3972 write in @code{~/.config/guix/channels.scm} this specification:
3975 ;; Tell 'guix pull' to use my own repo.
3978 (url "https://example.org/my-guix.git")
3979 (branch "super-hacks")))
3983 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3984 branch of the repository at @code{example.org}.
3986 @subsection Specifying Additional Channels
3988 @cindex extending the package collection (channels)
3989 @cindex personal packages (channels)
3990 @cindex channels, for personal packages
3991 You can also specify @emph{additional channels} to pull from. Let's say you
3992 have a bunch of custom package variants or personal packages that you think
3993 would make little sense to contribute to the Guix project, but would like to
3994 have these packages transparently available to you at the command line. You
3995 would first write modules containing those package definitions (@pxref{Package
3996 Modules}), maintain them in a Git repository, and then you and anyone else can
3997 use it as an additional channel to get packages from. Neat, no?
3999 @c What follows stems from discussions at
4000 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
4001 @c earlier discussions on guix-devel@gnu.org.
4003 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
4004 publish your personal channel to the world, we would like to share a few words
4009 Before publishing a channel, please consider contributing your package
4010 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
4011 to free software of all sorts, and packages in Guix proper are readily
4012 available to all Guix users and benefit from the project's quality assurance
4016 When you maintain package definitions outside Guix, we, Guix developers,
4017 consider that @emph{the compatibility burden is on you}. Remember that
4018 package modules and package definitions are just Scheme code that uses various
4019 programming interfaces (APIs). We want to remain free to change these APIs to
4020 keep improving Guix, possibly in ways that break your channel. We never
4021 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
4025 Corollary: if you're using an external channel and that channel breaks, please
4026 @emph{report the issue to the channel authors}, not to the Guix project.
4029 You've been warned! Having said this, we believe external channels are a
4030 practical way to exert your freedom to augment Guix' package collection and to
4031 share your improvements, which are basic tenets of
4032 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
4033 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
4036 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
4037 @command{guix pull} to pull from it @emph{in addition} to the default Guix
4040 @vindex %default-channels
4042 ;; Add my personal packages to those Guix provides.
4044 (name 'my-personal-packages)
4045 (url "https://example.org/personal-packages.git"))
4050 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4051 add a channel the list of channels that the variable @code{%default-channels}
4052 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4053 Manual}). With this file in place, @command{guix pull} builds not only Guix
4054 but also the package modules from your own repository. The result in
4055 @file{~/.config/guix/current} is the union of Guix with your own package
4059 $ guix pull --list-generations
4061 Generation 19 Aug 27 2018 16:20:48
4063 repository URL: https://git.savannah.gnu.org/git/guix.git
4065 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4066 my-personal-packages dd3df5e
4067 repository URL: https://example.org/personal-packages.git
4069 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4070 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
4071 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4075 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4076 both Guix and packages from the @code{my-personal-packages} channel. Among
4077 the new and upgraded packages that are listed, some like @code{my-gimp} and
4078 @code{my-emacs-with-cool-features} might come from
4079 @code{my-personal-packages}, while others come from the Guix default channel.
4081 To create a channel, create a Git repository containing your own package
4082 modules and make it available. The repository can contain anything, but a
4083 useful channel will contain Guile modules that export packages. Once you
4084 start using a channel, Guix will behave as if the root directory of that
4085 channel's Git repository has been added to the Guile load path (@pxref{Load
4086 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
4087 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
4088 module, then the module will be available under the name @code{(my-packages
4089 my-tools)}, and you will be able to use it like any other module
4090 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
4092 @cindex dependencies, channels
4093 @cindex meta-data, channels
4094 @subsection Declaring Channel Dependencies
4096 Channel authors may decide to augment a package collection provided by other
4097 channels. They can declare their channel to be dependent on other channels in
4098 a meta-data file @file{.guix-channel}, which is to be placed in the root of
4099 the channel repository.
4101 The meta-data file should contain a simple S-expression like this:
4108 (name some-collection)
4109 (url "https://example.org/first-collection.git"))
4111 (name some-other-collection)
4112 (url "https://example.org/second-collection.git")
4113 (branch "testing"))))
4116 In the above example this channel is declared to depend on two other channels,
4117 which will both be fetched automatically. The modules provided by the channel
4118 will be compiled in an environment where the modules of all these declared
4119 channels are available.
4121 For the sake of reliability and maintainability, you should avoid dependencies
4122 on channels that you don't control, and you should aim to keep the number of
4123 dependencies to a minimum.
4125 @cindex subdirectory, channels
4126 @subsection Package Modules in a Sub-directory
4128 As a channel author, you may want to keep your channel modules in a
4129 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4130 add a meta-data file @file{.guix-channel} that contains:
4138 @cindex news, for channels
4139 @subsection Writing Channel News
4141 Channel authors may occasionally want to communicate to their users
4142 information about important changes in the channel. You'd send them all
4143 an email, but that's not convenient.
4145 Instead, channels can provide a @dfn{news file}; when the channel users
4146 run @command{guix pull}, that news file is automatically read and
4147 @command{guix pull --news} can display the announcements that correspond
4148 to the new commits that have been pulled, if any.
4150 To do that, channel authors must first declare the name of the news file
4151 in their @file{.guix-channel} file:
4156 (news-file "etc/news.txt"))
4159 The news file itself, @file{etc/news.txt} in this example, must look
4160 something like this:
4165 (entry (tag "the-bug-fix")
4166 (title (en "Fixed terrible bug")
4168 (body (en "@@emph@{Good news@}! It's fixed!")
4169 (eo "Certe ĝi pli bone funkcias nun!")))
4170 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4171 (title (en "Added a great package")
4172 (ca "Què vol dir guix?"))
4173 (body (en "Don't miss the @@code@{hello@} package!"))))
4176 The file consists of a list of @dfn{news entries}. Each entry is
4177 associated with a commit or tag: it describes changes made in this
4178 commit, possibly in preceding commits as well. Users see entries only
4179 the first time they obtain the commit the entry refers to.
4181 The @code{title} field should be a one-line summary while @code{body}
4182 can be arbitrarily long, and both can contain Texinfo markup
4183 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4184 a list of language tag/message tuples, which allows @command{guix pull}
4185 to display news in the language that corresponds to the user's locale.
4187 If you want to translate news using a gettext-based workflow, you can
4188 extract translatable strings with @command{xgettext} (@pxref{xgettext
4189 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4190 you write news entries in English first, the command below creates a PO
4191 file containing the strings to translate:
4194 xgettext -o news.po -l scheme -ken etc/news.scm
4197 To sum up, yes, you could use your channel as a blog. But beware, this
4198 is @emph{not quite} what your users might expect.
4200 @subsection Replicating Guix
4202 @cindex pinning, channels
4203 @cindex replicating Guix
4204 @cindex reproducibility, of Guix
4205 The @command{guix pull --list-generations} output above shows precisely which
4206 commits were used to build this instance of Guix. We can thus replicate it,
4207 say, on another machine, by providing a channel specification in
4208 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4211 ;; Deploy specific commits of my channels of interest.
4214 (url "https://git.savannah.gnu.org/git/guix.git")
4215 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
4217 (name 'my-personal-packages)
4218 (url "https://example.org/personal-packages.git")
4219 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4222 The @command{guix describe --format=channels} command can even generate this
4223 list of channels directly (@pxref{Invoking guix describe}). The resulting
4224 file can be used with the -C options of @command{guix pull}
4225 (@pxref{Invoking guix pull}) or @command{guix time-machine}
4226 (@pxref{Invoking guix time-machine}).
4228 At this point the two machines run the @emph{exact same Guix}, with access to
4229 the @emph{exact same packages}. The output of @command{guix build gimp} on
4230 one machine will be exactly the same, bit for bit, as the output of the same
4231 command on the other machine. It also means both machines have access to all
4232 the source code of Guix and, transitively, to all the source code of every
4235 This gives you super powers, allowing you to track the provenance of binary
4236 artifacts with very fine grain, and to reproduce software environments at
4237 will---some sort of ``meta reproducibility'' capabilities, if you will.
4238 @xref{Inferiors}, for another way to take advantage of these super powers.
4240 @node Invoking guix time-machine
4241 @section Invoking @command{guix time-machine}
4243 @cindex @command{guix time-machine}
4244 @cindex pinning, channels
4245 @cindex replicating Guix
4246 @cindex reproducibility, of Guix
4248 The @command{guix time-machine} command provides access to other
4249 revisions of Guix, for example to install older versions of packages,
4250 or to reproduce a computation in an identical environment. The revision
4251 of Guix to be used is defined by a commit or by a channel
4252 description file created by @command{guix describe}
4253 (@pxref{Invoking guix describe}).
4255 The general syntax is:
4258 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4261 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4262 @command{guix} command of the specified revision. The @var{options} that define
4263 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4266 @item --url=@var{url}
4267 @itemx --commit=@var{commit}
4268 @itemx --branch=@var{branch}
4269 Use the @code{guix} channel from the specified @var{url}, at the
4270 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4271 string), or @var{branch}.
4273 @item --channels=@var{file}
4274 @itemx -C @var{file}
4275 Read the list of channels from @var{file}. @var{file} must contain
4276 Scheme code that evaluates to a list of channel objects.
4277 @xref{Channels} for more information.
4280 As for @command{guix pull}, the absence of any options means that the
4281 the latest commit on the master branch will be used. The command
4284 guix time-machine -- build hello
4287 will thus build the package @code{hello} as defined in the master branch,
4288 which is in general a newer revision of Guix than you have installed.
4289 Time travel works in both directions!
4291 Note that @command{guix time-machine} can trigger builds of channels and
4292 their dependencies, and these are controlled by the standard build
4293 options (@pxref{Common Build Options}).
4298 @c TODO: Remove this once we're more confident about API stability.
4300 The functionality described here is a ``technology preview'' as of version
4301 @value{VERSION}. As such, the interface is subject to change.
4305 @cindex composition of Guix revisions
4306 Sometimes you might need to mix packages from the revision of Guix you're
4307 currently running with packages available in a different revision of Guix.
4308 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4309 revisions in arbitrary ways.
4311 @cindex inferior packages
4312 Technically, an ``inferior'' is essentially a separate Guix process connected
4313 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4314 @code{(guix inferior)} module allows you to create inferiors and to
4315 communicate with them. It also provides a high-level interface to browse and
4316 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4318 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4319 to interact with a separate revision of Guix. For example, let's assume you
4320 want to install in your profile the current @code{guile} package, along with
4321 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4322 because the newer @code{guile-json} has an incompatible API and you want to
4323 run your code against the old API@. To do that, you could write a manifest for
4324 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4325 manifest, you would create an inferior for that old Guix revision you care
4326 about, and you would look up the @code{guile-json} package in the inferior:
4329 (use-modules (guix inferior) (guix channels)
4330 (srfi srfi-1)) ;for 'first'
4333 ;; This is the old revision from which we want to
4334 ;; extract guile-json.
4337 (url "https://git.savannah.gnu.org/git/guix.git")
4339 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4342 ;; An inferior representing the above revision.
4343 (inferior-for-channels channels))
4345 ;; Now create a manifest with the current "guile" package
4346 ;; and the old "guile-json" package.
4348 (list (first (lookup-inferior-packages inferior "guile-json"))
4349 (specification->package "guile")))
4352 On its first run, @command{guix package --manifest} might have to build the
4353 channel you specified before it can create the inferior; subsequent runs will
4354 be much faster because the Guix revision will be cached.
4356 The @code{(guix inferior)} module provides the following procedures to open an
4359 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4360 [#:cache-directory] [#:ttl]
4361 Return an inferior for @var{channels}, a list of channels. Use the cache at
4362 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4363 This procedure opens a new connection to the build daemon.
4365 As a side effect, this procedure may build or substitute binaries for
4366 @var{channels}, which can take time.
4369 @deffn {Scheme Procedure} open-inferior @var{directory} @
4370 [#:command "bin/guix"]
4371 Open the inferior Guix in @var{directory}, running
4372 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4373 the inferior could not be launched.
4376 @cindex inferior packages
4377 The procedures listed below allow you to obtain and manipulate inferior
4380 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4381 Return the list of packages known to @var{inferior}.
4384 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4386 Return the sorted list of inferior packages matching @var{name} in
4387 @var{inferior}, with highest version numbers first. If @var{version} is true,
4388 return only packages with a version number prefixed by @var{version}.
4391 @deffn {Scheme Procedure} inferior-package? @var{obj}
4392 Return true if @var{obj} is an inferior package.
4395 @deffn {Scheme Procedure} inferior-package-name @var{package}
4396 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4397 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4398 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4399 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4400 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4401 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4402 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4403 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4404 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4405 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4406 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4407 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4408 These procedures are the counterpart of package record accessors
4409 (@pxref{package Reference}). Most of them work by querying the inferior
4410 @var{package} comes from, so the inferior must still be live when you call
4414 Inferior packages can be used transparently like any other package or
4415 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4416 transparently handled by the @code{packages->manifest} procedure, which is
4417 commonly use in manifests (@pxref{Invoking guix package, the
4418 @option{--manifest} option of @command{guix package}}). Thus you can insert
4419 an inferior package pretty much anywhere you would insert a regular package:
4420 in manifests, in the @code{packages} field of your @code{operating-system}
4421 declaration, and so on.
4423 @node Invoking guix describe
4424 @section Invoking @command{guix describe}
4426 @cindex reproducibility
4427 @cindex replicating Guix
4428 Often you may want to answer questions like: ``Which revision of Guix am I
4429 using?'' or ``Which channels am I using?'' This is useful information in many
4430 situations: if you want to @emph{replicate} an environment on a different
4431 machine or user account, if you want to report a bug or to determine what
4432 change in the channels you are using caused it, or if you want to record your
4433 system state for reproducibility purposes. The @command{guix describe}
4434 command answers these questions.
4436 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4437 displays the channel(s) that it was built from, including their repository URL
4438 and commit IDs (@pxref{Channels}):
4442 Generation 10 Sep 03 2018 17:32:44 (current)
4444 repository URL: https://git.savannah.gnu.org/git/guix.git
4446 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4449 If you're familiar with the Git version control system, this is similar in
4450 spirit to @command{git describe}; the output is also similar to that of
4451 @command{guix pull --list-generations}, but limited to the current generation
4452 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4453 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4454 information is all it takes to describe the revision of Guix you're using, and
4455 also to replicate it.
4457 To make it easier to replicate Guix, @command{guix describe} can also be asked
4458 to return a list of channels instead of the human-readable description above:
4461 $ guix describe -f channels
4464 (url "https://git.savannah.gnu.org/git/guix.git")
4466 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4470 You can save this to a file and feed it to @command{guix pull -C} on some
4471 other machine or at a later point in time, which will instantiate @emph{this
4472 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4473 From there on, since you're able to deploy the same revision of Guix, you can
4474 just as well @emph{replicate a complete software environment}. We humbly
4475 think that this is @emph{awesome}, and we hope you'll like it too!
4477 The details of the options supported by @command{guix describe} are as
4481 @item --format=@var{format}
4482 @itemx -f @var{format}
4483 Produce output in the specified @var{format}, one of:
4487 produce human-readable output;
4489 produce a list of channel specifications that can be passed to @command{guix
4490 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4494 produce a list of channel specifications in JSON format;
4496 produce a list of channel specifications in Recutils format.
4499 @item --list-formats
4500 Display available formats for @option{--format} option.
4502 @item --profile=@var{profile}
4503 @itemx -p @var{profile}
4504 Display information about @var{profile}.
4507 @node Invoking guix archive
4508 @section Invoking @command{guix archive}
4510 @cindex @command{guix archive}
4512 The @command{guix archive} command allows users to @dfn{export} files
4513 from the store into a single archive, and to later @dfn{import} them on
4514 a machine that runs Guix.
4515 In particular, it allows store files to be transferred from one machine
4516 to the store on another machine.
4519 If you're looking for a way to produce archives in a format suitable for
4520 tools other than Guix, @pxref{Invoking guix pack}.
4523 @cindex exporting store items
4524 To export store files as an archive to standard output, run:
4527 guix archive --export @var{options} @var{specifications}...
4530 @var{specifications} may be either store file names or package
4531 specifications, as for @command{guix package} (@pxref{Invoking guix
4532 package}). For instance, the following command creates an archive
4533 containing the @code{gui} output of the @code{git} package and the main
4534 output of @code{emacs}:
4537 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4540 If the specified packages are not built yet, @command{guix archive}
4541 automatically builds them. The build process may be controlled with the
4542 common build options (@pxref{Common Build Options}).
4544 To transfer the @code{emacs} package to a machine connected over SSH,
4548 guix archive --export -r emacs | ssh the-machine guix archive --import
4552 Similarly, a complete user profile may be transferred from one machine
4553 to another like this:
4556 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4557 ssh the-machine guix archive --import
4561 However, note that, in both examples, all of @code{emacs} and the
4562 profile as well as all of their dependencies are transferred (due to
4563 @option{-r}), regardless of what is already available in the store on
4564 the target machine. The @option{--missing} option can help figure out
4565 which items are missing from the target store. The @command{guix copy}
4566 command simplifies and optimizes this whole process, so this is probably
4567 what you should use in this case (@pxref{Invoking guix copy}).
4569 @cindex nar, archive format
4570 @cindex normalized archive (nar)
4571 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4572 comparable in spirit to `tar', but with differences
4573 that make it more appropriate for our purposes. First, rather than
4574 recording all Unix metadata for each file, the nar format only mentions
4575 the file type (regular, directory, or symbolic link); Unix permissions
4576 and owner/group are dismissed. Second, the order in which directory
4577 entries are stored always follows the order of file names according to
4578 the C locale collation order. This makes archive production fully
4581 When exporting, the daemon digitally signs the contents of the archive,
4582 and that digital signature is appended. When importing, the daemon
4583 verifies the signature and rejects the import in case of an invalid
4584 signature or if the signing key is not authorized.
4585 @c FIXME: Add xref to daemon doc about signatures.
4587 The main options are:
4591 Export the specified store files or packages (see below). Write the
4592 resulting archive to the standard output.
4594 Dependencies are @emph{not} included in the output, unless
4595 @option{--recursive} is passed.
4599 When combined with @option{--export}, this instructs @command{guix archive}
4600 to include dependencies of the given items in the archive. Thus, the
4601 resulting archive is self-contained: it contains the closure of the
4602 exported store items.
4605 Read an archive from the standard input, and import the files listed
4606 therein into the store. Abort if the archive has an invalid digital
4607 signature, or if it is signed by a public key not among the authorized
4608 keys (see @option{--authorize} below).
4611 Read a list of store file names from the standard input, one per line,
4612 and write on the standard output the subset of these files missing from
4615 @item --generate-key[=@var{parameters}]
4616 @cindex signing, archives
4617 Generate a new key pair for the daemon. This is a prerequisite before
4618 archives can be exported with @option{--export}. Note that this
4619 operation usually takes time, because it needs to gather enough entropy
4620 to generate the key pair.
4622 The generated key pair is typically stored under @file{/etc/guix}, in
4623 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4624 key, which must be kept secret). When @var{parameters} is omitted,
4625 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4626 versions before 1.6.0, it is a 4096-bit RSA key.
4627 Alternatively, @var{parameters} can specify
4628 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4629 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4630 Libgcrypt Reference Manual}).
4633 @cindex authorizing, archives
4634 Authorize imports signed by the public key passed on standard input.
4635 The public key must be in ``s-expression advanced format''---i.e., the
4636 same format as the @file{signing-key.pub} file.
4638 The list of authorized keys is kept in the human-editable file
4639 @file{/etc/guix/acl}. The file contains
4640 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4641 s-expressions''} and is structured as an access-control list in the
4642 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4645 @item --extract=@var{directory}
4646 @itemx -x @var{directory}
4647 Read a single-item archive as served by substitute servers
4648 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4649 low-level operation needed in only very narrow use cases; see below.
4651 For example, the following command extracts the substitute for Emacs
4652 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4656 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4657 | gunzip | guix archive -x /tmp/emacs
4660 Single-item archives are different from multiple-item archives produced
4661 by @command{guix archive --export}; they contain a single store item,
4662 and they do @emph{not} embed a signature. Thus this operation does
4663 @emph{no} signature verification and its output should be considered
4666 The primary purpose of this operation is to facilitate inspection of
4667 archive contents coming from possibly untrusted substitute servers
4668 (@pxref{Invoking guix challenge}).
4672 Read a single-item archive as served by substitute servers
4673 (@pxref{Substitutes}) and print the list of files it contains, as in
4678 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4679 | lzip -d | guix archive -t
4685 @c *********************************************************************
4687 @chapter Development
4689 @cindex software development
4690 If you are a software developer, Guix provides tools that you should find
4691 helpful---independently of the language you're developing in. This is what
4692 this chapter is about.
4694 The @command{guix environment} command provides a convenient way to set up
4695 @dfn{development environments} containing all the dependencies and tools
4696 necessary to work on the software package of your choice. The @command{guix
4697 pack} command allows you to create @dfn{application bundles} that can be
4698 easily distributed to users who do not run Guix.
4701 * Invoking guix environment:: Setting up development environments.
4702 * Invoking guix pack:: Creating software bundles.
4703 * The GCC toolchain:: Working with languages supported by GCC.
4706 @node Invoking guix environment
4707 @section Invoking @command{guix environment}
4709 @cindex reproducible build environments
4710 @cindex development environments
4711 @cindex @command{guix environment}
4712 @cindex environment, package build environment
4713 The purpose of @command{guix environment} is to assist hackers in
4714 creating reproducible development environments without polluting their
4715 package profile. The @command{guix environment} tool takes one or more
4716 packages, builds all of their inputs, and creates a shell
4717 environment to use them.
4719 The general syntax is:
4722 guix environment @var{options} @var{package}@dots{}
4725 The following example spawns a new shell set up for the development of
4729 guix environment guile
4732 If the needed dependencies are not built yet, @command{guix environment}
4733 automatically builds them. The environment of the new shell is an
4734 augmented version of the environment that @command{guix environment} was
4735 run in. It contains the necessary search paths for building the given
4736 package added to the existing environment variables. To create
4737 a ``pure'' environment, in which the original environment variables have
4738 been unset, use the @option{--pure} option@footnote{Users sometimes
4739 wrongfully augment environment variables such as @env{PATH} in their
4740 @file{~/.bashrc} file. As a consequence, when @command{guix
4741 environment} launches it, Bash may read @file{~/.bashrc}, thereby
4742 introducing ``impurities'' in these environment variables. It is an
4743 error to define such environment variables in @file{.bashrc}; instead,
4744 they should be defined in @file{.bash_profile}, which is sourced only by
4745 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
4746 Manual}, for details on Bash start-up files.}.
4748 @vindex GUIX_ENVIRONMENT
4749 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
4750 variable in the shell it spawns; its value is the file name of the
4751 profile of this environment. This allows users to, say, define a
4752 specific prompt for development environments in their @file{.bashrc}
4753 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4756 if [ -n "$GUIX_ENVIRONMENT" ]
4758 export PS1="\u@@\h \w [dev]\$ "
4763 ...@: or to browse the profile:
4766 $ ls "$GUIX_ENVIRONMENT/bin"
4769 Additionally, more than one package may be specified, in which case the
4770 union of the inputs for the given packages are used. For example, the
4771 command below spawns a shell where all of the dependencies of both Guile
4772 and Emacs are available:
4775 guix environment guile emacs
4778 Sometimes an interactive shell session is not desired. An arbitrary
4779 command may be invoked by placing the @code{--} token to separate the
4780 command from the rest of the arguments:
4783 guix environment guile -- make -j4
4786 In other situations, it is more convenient to specify the list of
4787 packages needed in the environment. For example, the following command
4788 runs @command{python} from an environment containing Python@tie{}2.7 and
4792 guix environment --ad-hoc python2-numpy python-2.7 -- python
4795 Furthermore, one might want the dependencies of a package and also some
4796 additional packages that are not build-time or runtime dependencies, but
4797 are useful when developing nonetheless. Because of this, the
4798 @option{--ad-hoc} flag is positional. Packages appearing before
4799 @option{--ad-hoc} are interpreted as packages whose dependencies will be
4800 added to the environment. Packages appearing after are interpreted as
4801 packages that will be added to the environment directly. For example,
4802 the following command creates a Guix development environment that
4803 additionally includes Git and strace:
4806 guix environment --pure guix --ad-hoc git strace
4810 Sometimes it is desirable to isolate the environment as much as
4811 possible, for maximal purity and reproducibility. In particular, when
4812 using Guix on a host distro that is not Guix System, it is desirable to
4813 prevent access to @file{/usr/bin} and other system-wide resources from
4814 the development environment. For example, the following command spawns
4815 a Guile REPL in a ``container'' where only the store and the current
4816 working directory are mounted:
4819 guix environment --ad-hoc --container guile -- guile
4823 The @option{--container} option requires Linux-libre 3.19 or newer.
4826 @cindex certificates
4827 Another typical use case for containers is to run security-sensitive
4828 applications such as a web browser. To run Eolie, we must expose and
4829 share some files and directories; we include @code{nss-certs} and expose
4830 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
4831 the @env{DISPLAY} environment variable since containerized graphical
4832 applications won't display without it.
4835 guix environment --preserve='^DISPLAY$' --container --network \
4836 --expose=/etc/machine-id \
4837 --expose=/etc/ssl/certs/ \
4838 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
4839 --ad-hoc eolie nss-certs dbus -- eolie
4842 The available options are summarized below.
4845 @item --root=@var{file}
4846 @itemx -r @var{file}
4847 @cindex persistent environment
4848 @cindex garbage collector root, for environments
4849 Make @var{file} a symlink to the profile for this environment, and
4850 register it as a garbage collector root.
4852 This is useful if you want to protect your environment from garbage
4853 collection, to make it ``persistent''.
4855 When this option is omitted, the environment is protected from garbage
4856 collection only for the duration of the @command{guix environment}
4857 session. This means that next time you recreate the same environment,
4858 you could have to rebuild or re-download packages. @xref{Invoking guix
4859 gc}, for more on GC roots.
4861 @item --expression=@var{expr}
4862 @itemx -e @var{expr}
4863 Create an environment for the package or list of packages that
4864 @var{expr} evaluates to.
4866 For example, running:
4869 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4872 starts a shell with the environment for this specific variant of the
4878 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4881 starts a shell with all the base system packages available.
4883 The above commands only use the default output of the given packages.
4884 To select other outputs, two element tuples can be specified:
4887 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4890 @item --load=@var{file}
4891 @itemx -l @var{file}
4892 Create an environment for the package or list of packages that the code
4893 within @var{file} evaluates to.
4895 As an example, @var{file} might contain a definition like this
4896 (@pxref{Defining Packages}):
4899 @verbatiminclude environment-gdb.scm
4902 @item --manifest=@var{file}
4903 @itemx -m @var{file}
4904 Create an environment for the packages contained in the manifest object
4905 returned by the Scheme code in @var{file}. This option can be repeated
4906 several times, in which case the manifests are concatenated.
4908 This is similar to the same-named option in @command{guix package}
4909 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4913 Include all specified packages in the resulting environment, as if an
4914 @i{ad hoc} package were defined with them as inputs. This option is
4915 useful for quickly creating an environment without having to write a
4916 package expression to contain the desired inputs.
4918 For instance, the command:
4921 guix environment --ad-hoc guile guile-sdl -- guile
4924 runs @command{guile} in an environment where Guile and Guile-SDL are
4927 Note that this example implicitly asks for the default output of
4928 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4929 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4930 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4932 This option may be composed with the default behavior of @command{guix
4933 environment}. Packages appearing before @option{--ad-hoc} are
4934 interpreted as packages whose dependencies will be added to the
4935 environment, the default behavior. Packages appearing after are
4936 interpreted as packages that will be added to the environment directly.
4939 Unset existing environment variables when building the new environment, except
4940 those specified with @option{--preserve} (see below). This has the effect of
4941 creating an environment in which search paths only contain package inputs.
4943 @item --preserve=@var{regexp}
4944 @itemx -E @var{regexp}
4945 When used alongside @option{--pure}, preserve the environment variables
4946 matching @var{regexp}---in other words, put them on a ``white list'' of
4947 environment variables that must be preserved. This option can be repeated
4951 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4955 This example runs @command{mpirun} in a context where the only environment
4956 variables defined are @env{PATH}, environment variables whose name starts
4957 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
4960 @item --search-paths
4961 Display the environment variable definitions that make up the
4964 @item --system=@var{system}
4965 @itemx -s @var{system}
4966 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4971 Run @var{command} within an isolated container. The current working
4972 directory outside the container is mapped inside the container.
4973 Additionally, unless overridden with @option{--user}, a dummy home
4974 directory is created that matches the current user's home directory, and
4975 @file{/etc/passwd} is configured accordingly.
4977 The spawned process runs as the current user outside the container. Inside
4978 the container, it has the same UID and GID as the current user, unless
4979 @option{--user} is passed (see below).
4983 For containers, share the network namespace with the host system.
4984 Containers created without this flag only have access to the loopback
4987 @item --link-profile
4989 For containers, link the environment profile to @file{~/.guix-profile}
4990 within the container. This is equivalent to running the command
4991 @samp{ln -s $GUIX_ENVIRONMENT ~/.guix-profile} within the container.
4992 Linking will fail and abort the environment if the directory already
4993 exists, which will certainly be the case if @command{guix environment}
4994 was invoked in the user's home directory.
4996 Certain packages are configured to look in @file{~/.guix-profile} for
4997 configuration files and data;@footnote{For example, the
4998 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
4999 for additional fonts.} @option{--link-profile} allows these programs to
5000 behave as expected within the environment.
5002 @item --user=@var{user}
5003 @itemx -u @var{user}
5004 For containers, use the username @var{user} in place of the current
5005 user. The generated @file{/etc/passwd} entry within the container will
5006 contain the name @var{user}, the home directory will be
5007 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5008 the UID and GID inside the container are 1000. @var{user}
5009 need not exist on the system.
5011 Additionally, any shared or exposed path (see @option{--share} and
5012 @option{--expose} respectively) whose target is within the current user's
5013 home directory will be remapped relative to @file{/home/USER}; this
5014 includes the automatic mapping of the current working directory.
5017 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5019 guix environment --container --user=foo \
5020 --expose=$HOME/test \
5021 --expose=/tmp/target=$HOME/target
5024 While this will limit the leaking of user identity through home paths
5025 and each of the user fields, this is only one useful component of a
5026 broader privacy/anonymity solution---not one in and of itself.
5029 For containers, the default behavior is to share the current working
5030 directory with the isolated container and immediately change to that
5031 directory within the container. If this is undesirable,
5032 @option{--no-cwd} will cause the current working directory to @emph{not}
5033 be automatically shared and will change to the user's home directory
5034 within the container instead. See also @option{--user}.
5036 @item --expose=@var{source}[=@var{target}]
5037 @itemx --share=@var{source}[=@var{target}]
5038 For containers, @option{--expose} (resp. @option{--share}) exposes the
5039 file system @var{source} from the host system as the read-only
5040 (resp. writable) file system @var{target} within the container. If
5041 @var{target} is not specified, @var{source} is used as the target mount
5042 point in the container.
5044 The example below spawns a Guile REPL in a container in which the user's
5045 home directory is accessible read-only via the @file{/exchange}
5049 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5054 @command{guix environment}
5055 also supports all of the common build options that @command{guix
5056 build} supports (@pxref{Common Build Options}) as well as package
5057 transformation options (@pxref{Package Transformation Options}).
5059 @node Invoking guix pack
5060 @section Invoking @command{guix pack}
5062 Occasionally you want to pass software to people who are not (yet!)
5063 lucky enough to be using Guix. You'd tell them to run @command{guix
5064 package -i @var{something}}, but that's not possible in this case. This
5065 is where @command{guix pack} comes in.
5068 If you are looking for ways to exchange binaries among machines that
5069 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5070 publish}, and @ref{Invoking guix archive}.
5075 @cindex application bundle
5076 @cindex software bundle
5077 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5078 @dfn{software bundle}: it creates a tarball or some other archive
5079 containing the binaries of the software you're interested in, and all
5080 its dependencies. The resulting archive can be used on any machine that
5081 does not have Guix, and people can run the exact same binaries as those
5082 you have with Guix. The pack itself is created in a bit-reproducible
5083 fashion, so anyone can verify that it really contains the build results
5084 that you pretend to be shipping.
5086 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5087 their dependencies, you can run:
5090 $ guix pack guile emacs geiser
5092 /gnu/store/@dots{}-pack.tar.gz
5095 The result here is a tarball containing a @file{/gnu/store} directory
5096 with all the relevant packages. The resulting tarball contains a
5097 @dfn{profile} with the three packages of interest; the profile is the
5098 same as would be created by @command{guix package -i}. It is this
5099 mechanism that is used to create Guix's own standalone binary tarball
5100 (@pxref{Binary Installation}).
5102 Users of this pack would have to run
5103 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5104 find inconvenient. To work around it, you can create, say, a
5105 @file{/opt/gnu/bin} symlink to the profile:
5108 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5112 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5114 @cindex relocatable binaries, with @command{guix pack}
5115 What if the recipient of your pack does not have root privileges on
5116 their machine, and thus cannot unpack it in the root file system? In
5117 that case, you will want to use the @option{--relocatable} option (see
5118 below). This option produces @dfn{relocatable binaries}, meaning they
5119 they can be placed anywhere in the file system hierarchy: in the example
5120 above, users can unpack your tarball in their home directory and
5121 directly run @file{./opt/gnu/bin/guile}.
5123 @cindex Docker, build an image with guix pack
5124 Alternatively, you can produce a pack in the Docker image format using
5125 the following command:
5128 guix pack -f docker -S /bin=bin guile guile-readline
5132 The result is a tarball that can be passed to the @command{docker load}
5133 command, followed by @code{docker run}:
5136 docker load < @var{file}
5137 docker run -ti guile-guile-readline /bin/guile
5141 where @var{file} is the image returned by @var{guix pack}, and
5142 @code{guile-guile-readline} is its ``image tag''. See the
5143 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5144 documentation} for more information.
5146 @cindex Singularity, build an image with guix pack
5147 @cindex SquashFS, build an image with guix pack
5148 Yet another option is to produce a SquashFS image with the following
5152 guix pack -f squashfs bash guile emacs geiser
5156 The result is a SquashFS file system image that can either be mounted or
5157 directly be used as a file system container image with the
5158 @uref{https://www.sylabs.io/docs/, Singularity container execution
5159 environment}, using commands like @command{singularity shell} or
5160 @command{singularity exec}.
5162 Several command-line options allow you to customize your pack:
5165 @item --format=@var{format}
5166 @itemx -f @var{format}
5167 Produce a pack in the given @var{format}.
5169 The available formats are:
5173 This is the default format. It produces a tarball containing all the
5174 specified binaries and symlinks.
5177 This produces a tarball that follows the
5178 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5179 Docker Image Specification}. The ``repository name'' as it appears in
5180 the output of the @command{docker images} command is computed from
5181 package names passed on the command line or in the manifest file.
5184 This produces a SquashFS image containing all the specified binaries and
5185 symlinks, as well as empty mount points for virtual file systems like
5189 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5190 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5191 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5192 with something like:
5195 guix pack -f squashfs bash @dots{}
5198 If you forget the @code{bash} (or similar) package, @command{singularity
5199 run} and @command{singularity exec} will fail with an unhelpful ``no
5200 such file or directory'' message.
5204 @cindex relocatable binaries
5207 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5208 anywhere in the file system hierarchy and run from there.
5210 When this option is passed once, the resulting binaries require support for
5211 @dfn{user namespaces} in the kernel Linux; when passed
5212 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5213 PRoot support, can be thought of as the abbreviation of ``Really
5214 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
5215 other techniques if user namespaces are unavailable, and essentially
5216 work anywhere---see below for the implications.
5218 For example, if you create a pack containing Bash with:
5221 guix pack -RR -S /mybin=bin bash
5225 ...@: you can copy that pack to a machine that lacks Guix, and from your
5226 home directory as a normal user, run:
5234 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5235 @file{/gnu/store} shows up and contains all the dependencies of
5236 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5237 altogether! That is probably the simplest way to deploy Guix-built
5238 software on a non-Guix machine.
5241 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5242 the kernel Linux, which allows unprivileged users to mount or change root.
5243 Old versions of Linux did not support it, and some GNU/Linux distributions
5246 To produce relocatable binaries that work even in the absence of user
5247 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5248 case, binaries will try user namespace support and fall back to another
5249 @dfn{execution engine} if user namespaces are not supported. The
5250 following execution engines are supported:
5254 Try user namespaces and fall back to PRoot if user namespaces are not
5255 supported (see below).
5258 Try user namespaces and fall back to Fakechroot if user namespaces are
5259 not supported (see below).
5262 Run the program through user namespaces and abort if they are not
5266 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
5267 provides the necessary
5268 support for file system virtualization. It achieves that by using the
5269 @code{ptrace} system call on the running program. This approach has the
5270 advantage to work without requiring special kernel support, but it incurs
5271 run-time overhead every time a system call is made.
5274 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
5275 Fakechroot} virtualizes file system accesses by intercepting calls to C
5276 library functions such as @code{open}, @code{stat}, @code{exec}, and so
5277 on. Unlike PRoot, it incurs very little overhead. However, it does not
5278 always work: for example, some file system accesses made from within the
5279 C library are not intercepted, and file system accesses made @i{via}
5280 direct syscalls are not intercepted either, leading to erratic behavior.
5283 @vindex GUIX_EXECUTION_ENGINE
5284 When running a wrapped program, you can explicitly request one of the
5285 execution engines listed above by setting the
5286 @code{GUIX_EXECUTION_ENGINE} environment variable accordingly.
5289 @cindex entry point, for Docker images
5290 @item --entry-point=@var{command}
5291 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5292 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5293 support it. @var{command} must be relative to the profile contained in the
5296 The entry point specifies the command that tools like @code{docker run} or
5297 @code{singularity run} automatically start by default. For example, you can
5301 guix pack -f docker --entry-point=bin/guile guile
5304 The resulting pack can easily be loaded and @code{docker run} with no extra
5305 arguments will spawn @code{bin/guile}:
5308 docker load -i pack.tar.gz
5309 docker run @var{image-id}
5312 @item --expression=@var{expr}
5313 @itemx -e @var{expr}
5314 Consider the package @var{expr} evaluates to.
5316 This has the same purpose as the same-named option in @command{guix
5317 build} (@pxref{Additional Build Options, @option{--expression} in
5318 @command{guix build}}).
5320 @item --manifest=@var{file}
5321 @itemx -m @var{file}
5322 Use the packages contained in the manifest object returned by the Scheme
5323 code in @var{file}. This option can be repeated several times, in which
5324 case the manifests are concatenated.
5326 This has a similar purpose as the same-named option in @command{guix
5327 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5328 same manifest files. It allows you to define a collection of packages
5329 once and use it both for creating profiles and for creating archives
5330 for use on machines that do not have Guix installed. Note that you can
5331 specify @emph{either} a manifest file @emph{or} a list of packages,
5334 @item --system=@var{system}
5335 @itemx -s @var{system}
5336 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5337 the system type of the build host.
5339 @item --target=@var{triplet}
5340 @cindex cross-compilation
5341 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5342 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
5343 configuration triplets,, autoconf, Autoconf}).
5345 @item --compression=@var{tool}
5346 @itemx -C @var{tool}
5347 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5348 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
5351 @item --symlink=@var{spec}
5352 @itemx -S @var{spec}
5353 Add the symlinks specified by @var{spec} to the pack. This option can
5354 appear several times.
5356 @var{spec} has the form @code{@var{source}=@var{target}}, where
5357 @var{source} is the symlink that will be created and @var{target} is the
5360 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5361 symlink pointing to the @file{bin} sub-directory of the profile.
5363 @item --save-provenance
5364 Save provenance information for the packages passed on the command line.
5365 Provenance information includes the URL and commit of the channels in use
5368 Provenance information is saved in the
5369 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5370 usual package metadata---the name and version of each package, their
5371 propagated inputs, and so on. It is useful information to the recipient of
5372 the pack, who then knows how the pack was (supposedly) obtained.
5374 This option is not enabled by default because, like timestamps, provenance
5375 information contributes nothing to the build process. In other words, there
5376 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5377 Recording such ``silent'' metadata in the output thus potentially breaks the
5378 source-to-binary bitwise reproducibility property.
5380 @item --root=@var{file}
5381 @itemx -r @var{file}
5382 @cindex garbage collector root, for packs
5383 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5386 @item --localstatedir
5387 @itemx --profile-name=@var{name}
5388 Include the ``local state directory'', @file{/var/guix}, in the resulting
5389 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5390 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5391 @file{~root/.guix-profile}.
5393 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5394 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5395 the pack means that the store is ``complete'' and manageable by Guix;
5396 not providing it pack means that the store is ``dead'': items cannot be
5397 added to it or removed from it after extraction of the pack.
5399 One use case for this is the Guix self-contained binary tarball
5400 (@pxref{Binary Installation}).
5404 Print the name of the derivation that builds the pack.
5407 Use the bootstrap binaries to build the pack. This option is only
5408 useful to Guix developers.
5411 In addition, @command{guix pack} supports all the common build options
5412 (@pxref{Common Build Options}) and all the package transformation
5413 options (@pxref{Package Transformation Options}).
5416 @node The GCC toolchain
5417 @section The GCC toolchain
5421 @cindex linker wrapper
5422 @cindex toolchain, for C development
5423 @cindex toolchain, for Fortran development
5425 If you need a complete toolchain for compiling and linking C or C++
5426 source code, use the @code{gcc-toolchain} package. This package
5427 provides a complete GCC toolchain for C/C++ development, including GCC
5428 itself, the GNU C Library (headers and binaries, plus debugging symbols
5429 in the @code{debug} output), Binutils, and a linker wrapper.
5431 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
5432 passed to the linker, add corresponding @code{-rpath} arguments, and
5433 invoke the actual linker with this new set of arguments. You can instruct the
5434 wrapper to refuse to link against libraries not in the store by setting the
5435 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
5437 The package @code{gfortran-toolchain} provides a complete GCC toolchain
5438 for Fortran development. For other languages, please use
5439 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
5441 @c *********************************************************************
5442 @node Programming Interface
5443 @chapter Programming Interface
5445 GNU Guix provides several Scheme programming interfaces (APIs) to
5446 define, build, and query packages. The first interface allows users to
5447 write high-level package definitions. These definitions refer to
5448 familiar packaging concepts, such as the name and version of a package,
5449 its build system, and its dependencies. These definitions can then be
5450 turned into concrete build actions.
5452 Build actions are performed by the Guix daemon, on behalf of users. In a
5453 standard setup, the daemon has write access to the store---the
5454 @file{/gnu/store} directory---whereas users do not. The recommended
5455 setup also has the daemon perform builds in chroots, under a specific
5456 build users, to minimize interference with the rest of the system.
5459 Lower-level APIs are available to interact with the daemon and the
5460 store. To instruct the daemon to perform a build action, users actually
5461 provide it with a @dfn{derivation}. A derivation is a low-level
5462 representation of the build actions to be taken, and the environment in
5463 which they should occur---derivations are to package definitions what
5464 assembly is to C programs. The term ``derivation'' comes from the fact
5465 that build results @emph{derive} from them.
5467 This chapter describes all these APIs in turn, starting from high-level
5468 package definitions.
5471 * Package Modules:: Packages from the programmer's viewpoint.
5472 * Defining Packages:: Defining new packages.
5473 * Build Systems:: Specifying how packages are built.
5474 * The Store:: Manipulating the package store.
5475 * Derivations:: Low-level interface to package derivations.
5476 * The Store Monad:: Purely functional interface to the store.
5477 * G-Expressions:: Manipulating build expressions.
5478 * Invoking guix repl:: Programming Guix in Guile
5481 @node Package Modules
5482 @section Package Modules
5484 From a programming viewpoint, the package definitions of the
5485 GNU distribution are provided by Guile modules in the @code{(gnu packages
5486 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5487 packages @dots{})} module name space are not necessarily ``GNU
5488 packages''. This module naming scheme follows the usual Guile module
5489 naming convention: @code{gnu} means that these modules are distributed
5490 as part of the GNU system, and @code{packages} identifies modules that
5491 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5492 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5493 module exports a variable named @code{emacs}, which is bound to a
5494 @code{<package>} object (@pxref{Defining Packages}).
5496 The @code{(gnu packages @dots{})} module name space is
5497 automatically scanned for packages by the command-line tools. For
5498 instance, when running @code{guix install emacs}, all the @code{(gnu
5499 packages @dots{})} modules are scanned until one that exports a package
5500 object whose name is @code{emacs} is found. This package search
5501 facility is implemented in the @code{(gnu packages)} module.
5503 @cindex customization, of packages
5504 @cindex package module search path
5505 Users can store package definitions in modules with different
5506 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5507 name and module name must match. For instance, the @code{(my-packages
5508 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5509 relative to the load path specified with @option{--load-path} or
5510 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5511 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5512 these package definitions visible to the user interfaces:
5516 By adding the directory containing your package modules to the search path
5517 with the @code{-L} flag of @command{guix package} and other commands
5518 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
5519 environment variable described below.
5522 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5523 pulls from it. A channel is essentially a Git repository containing package
5524 modules. @xref{Channels}, for more information on how to define and use
5528 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5530 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5531 This is a colon-separated list of directories to search for additional
5532 package modules. Directories listed in this variable take precedence
5533 over the own modules of the distribution.
5536 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5537 each package is built based solely on other packages in the
5538 distribution. The root of this dependency graph is a small set of
5539 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5540 bootstrap)} module. For more information on bootstrapping,
5541 @pxref{Bootstrapping}.
5543 @node Defining Packages
5544 @section Defining Packages
5546 The high-level interface to package definitions is implemented in the
5547 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5548 example, the package definition, or @dfn{recipe}, for the GNU Hello
5549 package looks like this:
5552 (define-module (gnu packages hello)
5553 #:use-module (guix packages)
5554 #:use-module (guix download)
5555 #:use-module (guix build-system gnu)
5556 #:use-module (guix licenses)
5557 #:use-module (gnu packages gawk))
5559 (define-public hello
5565 (uri (string-append "mirror://gnu/hello/hello-" version
5569 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5570 (build-system gnu-build-system)
5571 (arguments '(#:configure-flags '("--enable-silent-rules")))
5572 (inputs `(("gawk" ,gawk)))
5573 (synopsis "Hello, GNU world: An example GNU package")
5574 (description "Guess what GNU Hello prints!")
5575 (home-page "https://www.gnu.org/software/hello/")
5580 Without being a Scheme expert, the reader may have guessed the meaning
5581 of the various fields here. This expression binds the variable
5582 @code{hello} to a @code{<package>} object, which is essentially a record
5583 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5584 This package object can be inspected using procedures found in the
5585 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5586 returns---surprise!---@code{"hello"}.
5588 With luck, you may be able to import part or all of the definition of
5589 the package you are interested in from another repository, using the
5590 @code{guix import} command (@pxref{Invoking guix import}).
5592 In the example above, @var{hello} is defined in a module of its own,
5593 @code{(gnu packages hello)}. Technically, this is not strictly
5594 necessary, but it is convenient to do so: all the packages defined in
5595 modules under @code{(gnu packages @dots{})} are automatically known to
5596 the command-line tools (@pxref{Package Modules}).
5598 There are a few points worth noting in the above package definition:
5602 The @code{source} field of the package is an @code{<origin>} object
5603 (@pxref{origin Reference}, for the complete reference).
5604 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5605 meaning that the source is a file to be downloaded over FTP or HTTP.
5607 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5608 the GNU mirrors defined in @code{(guix download)}.
5610 The @code{sha256} field specifies the expected SHA256 hash of the file
5611 being downloaded. It is mandatory, and allows Guix to check the
5612 integrity of the file. The @code{(base32 @dots{})} form introduces the
5613 base32 representation of the hash. You can obtain this information with
5614 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5615 hash} (@pxref{Invoking guix hash}).
5618 When needed, the @code{origin} form can also have a @code{patches} field
5619 listing patches to be applied, and a @code{snippet} field giving a
5620 Scheme expression to modify the source code.
5623 @cindex GNU Build System
5624 The @code{build-system} field specifies the procedure to build the
5625 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5626 represents the familiar GNU Build System, where packages may be
5627 configured, built, and installed with the usual @code{./configure &&
5628 make && make check && make install} command sequence.
5631 The @code{arguments} field specifies options for the build system
5632 (@pxref{Build Systems}). Here it is interpreted by
5633 @var{gnu-build-system} as a request run @file{configure} with the
5634 @option{--enable-silent-rules} flag.
5640 What about these quote (@code{'}) characters? They are Scheme syntax to
5641 introduce a literal list; @code{'} is synonymous with @code{quote}.
5642 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5643 for details. Here the value of the @code{arguments} field is a list of
5644 arguments passed to the build system down the road, as with @code{apply}
5645 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5648 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5649 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5650 @code{#:configure-flags} is a keyword used to pass a keyword argument
5651 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5655 The @code{inputs} field specifies inputs to the build process---i.e.,
5656 build-time or run-time dependencies of the package. Here, we define an
5657 input called @code{"gawk"} whose value is that of the @var{gawk}
5658 variable; @var{gawk} is itself bound to a @code{<package>} object.
5660 @cindex backquote (quasiquote)
5663 @cindex comma (unquote)
5667 @findex unquote-splicing
5668 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5669 us to introduce a literal list in the @code{inputs} field, while
5670 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5671 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5674 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5675 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5676 of ensuring that they are present (@pxref{Build Systems}).
5678 However, any other dependencies need to be specified in the
5679 @code{inputs} field. Any dependency not specified here will simply be
5680 unavailable to the build process, possibly leading to a build failure.
5683 @xref{package Reference}, for a full description of possible fields.
5685 Once a package definition is in place, the
5686 package may actually be built using the @code{guix build} command-line
5687 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5688 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5689 package definition using the @command{guix edit} command
5690 (@pxref{Invoking guix edit}).
5691 @xref{Packaging Guidelines}, for
5692 more information on how to test package definitions, and
5693 @ref{Invoking guix lint}, for information on how to check a definition
5694 for style conformance.
5695 @vindex GUIX_PACKAGE_PATH
5696 Lastly, @pxref{Channels}, for information
5697 on how to extend the distribution by adding your own package definitions
5700 Finally, updating the package definition to a new upstream version
5701 can be partly automated by the @command{guix refresh} command
5702 (@pxref{Invoking guix refresh}).
5704 Behind the scenes, a derivation corresponding to the @code{<package>}
5705 object is first computed by the @code{package-derivation} procedure.
5706 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
5707 The build actions it prescribes may then be realized by using the
5708 @code{build-derivations} procedure (@pxref{The Store}).
5710 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5711 Return the @code{<derivation>} object of @var{package} for @var{system}
5712 (@pxref{Derivations}).
5714 @var{package} must be a valid @code{<package>} object, and @var{system}
5715 must be a string denoting the target system type---e.g.,
5716 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5717 must be a connection to the daemon, which operates on the store
5718 (@pxref{The Store}).
5722 @cindex cross-compilation
5723 Similarly, it is possible to compute a derivation that cross-builds a
5724 package for some other system:
5726 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5727 @var{package} @var{target} [@var{system}]
5728 Return the @code{<derivation>} object of @var{package} cross-built from
5729 @var{system} to @var{target}.
5731 @var{target} must be a valid GNU triplet denoting the target hardware
5732 and operating system, such as @code{"aarch64-linux-gnu"}
5733 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5736 @cindex package transformations
5737 @cindex input rewriting
5738 @cindex dependency tree rewriting
5739 Packages can be manipulated in arbitrary ways. An example of a useful
5740 transformation is @dfn{input rewriting}, whereby the dependency tree of
5741 a package is rewritten by replacing specific inputs by others:
5743 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5744 [@var{rewrite-name}]
5745 Return a procedure that, when passed a package, replaces its direct and
5746 indirect dependencies (but not its implicit inputs) according to
5747 @var{replacements}. @var{replacements} is a list of package pairs; the
5748 first element of each pair is the package to replace, and the second one
5751 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5752 the name of a package and returns its new name after rewrite.
5756 Consider this example:
5759 (define libressl-instead-of-openssl
5760 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5762 (package-input-rewriting `((,openssl . ,libressl))))
5764 (define git-with-libressl
5765 (libressl-instead-of-openssl git))
5769 Here we first define a rewriting procedure that replaces @var{openssl}
5770 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5771 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5772 This is exactly what the @option{--with-input} command-line option does
5773 (@pxref{Package Transformation Options, @option{--with-input}}).
5775 The following variant of @code{package-input-rewriting} can match packages to
5776 be replaced by name rather than by identity.
5778 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5779 Return a procedure that, given a package, applies the given @var{replacements} to
5780 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5781 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5782 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5783 replacement for that package.
5786 The example above could be rewritten this way:
5789 (define libressl-instead-of-openssl
5790 ;; Replace all the packages called "openssl" with LibreSSL.
5791 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5794 The key difference here is that, this time, packages are matched by spec and
5795 not by identity. In other words, any package in the graph that is called
5796 @code{openssl} will be replaced.
5798 A more generic procedure to rewrite a package dependency graph is
5799 @code{package-mapping}: it supports arbitrary changes to nodes in the
5802 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5803 Return a procedure that, given a package, applies @var{proc} to all the packages
5804 depended on and returns the resulting package. The procedure stops recursion
5805 when @var{cut?} returns true for a given package.
5809 * package Reference:: The package data type.
5810 * origin Reference:: The origin data type.
5814 @node package Reference
5815 @subsection @code{package} Reference
5817 This section summarizes all the options available in @code{package}
5818 declarations (@pxref{Defining Packages}).
5820 @deftp {Data Type} package
5821 This is the data type representing a package recipe.
5825 The name of the package, as a string.
5827 @item @code{version}
5828 The version of the package, as a string.
5831 An object telling how the source code for the package should be
5832 acquired. Most of the time, this is an @code{origin} object, which
5833 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5834 can also be any other ``file-like'' object such as a @code{local-file},
5835 which denotes a file from the local file system (@pxref{G-Expressions,
5836 @code{local-file}}).
5838 @item @code{build-system}
5839 The build system that should be used to build the package (@pxref{Build
5842 @item @code{arguments} (default: @code{'()})
5843 The arguments that should be passed to the build system. This is a
5844 list, typically containing sequential keyword-value pairs.
5846 @item @code{inputs} (default: @code{'()})
5847 @itemx @code{native-inputs} (default: @code{'()})
5848 @itemx @code{propagated-inputs} (default: @code{'()})
5849 @cindex inputs, of packages
5850 These fields list dependencies of the package. Each one is a list of
5851 tuples, where each tuple has a label for the input (a string) as its
5852 first element, a package, origin, or derivation as its second element,
5853 and optionally the name of the output thereof that should be used, which
5854 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5855 more on package outputs). For example, the list below specifies three
5859 `(("libffi" ,libffi)
5860 ("libunistring" ,libunistring)
5861 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5864 @cindex cross compilation, package dependencies
5865 The distinction between @code{native-inputs} and @code{inputs} is
5866 necessary when considering cross-compilation. When cross-compiling,
5867 dependencies listed in @code{inputs} are built for the @emph{target}
5868 architecture; conversely, dependencies listed in @code{native-inputs}
5869 are built for the architecture of the @emph{build} machine.
5871 @code{native-inputs} is typically used to list tools needed at
5872 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5873 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5874 this area (@pxref{Invoking guix lint}).
5876 @anchor{package-propagated-inputs}
5877 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5878 specified packages will be automatically installed alongside the package
5879 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5880 package}}, for information on how @command{guix package} deals with
5883 For example this is necessary when a C/C++ library needs headers of
5884 another library to compile, or when a pkg-config file refers to another
5885 one @i{via} its @code{Requires} field.
5887 Another example where @code{propagated-inputs} is useful is for languages
5888 that lack a facility to record the run-time search path akin to the
5889 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5890 more. To ensure that libraries written in those languages can find
5891 library code they depend on at run time, run-time dependencies must be
5892 listed in @code{propagated-inputs} rather than @code{inputs}.
5894 @item @code{outputs} (default: @code{'("out")})
5895 The list of output names of the package. @xref{Packages with Multiple
5896 Outputs}, for typical uses of additional outputs.
5898 @item @code{native-search-paths} (default: @code{'()})
5899 @itemx @code{search-paths} (default: @code{'()})
5900 A list of @code{search-path-specification} objects describing
5901 search-path environment variables honored by the package.
5903 @item @code{replacement} (default: @code{#f})
5904 This must be either @code{#f} or a package object that will be used as a
5905 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5908 @item @code{synopsis}
5909 A one-line description of the package.
5911 @item @code{description}
5912 A more elaborate description of the package.
5914 @item @code{license}
5915 @cindex license, of packages
5916 The license of the package; a value from @code{(guix licenses)},
5917 or a list of such values.
5919 @item @code{home-page}
5920 The URL to the home-page of the package, as a string.
5922 @item @code{supported-systems} (default: @code{%supported-systems})
5923 The list of systems supported by the package, as strings of the form
5924 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5926 @item @code{location} (default: source location of the @code{package} form)
5927 The source location of the package. It is useful to override this when
5928 inheriting from another package, in which case this field is not
5929 automatically corrected.
5933 @deffn {Scheme Syntax} this-package
5934 When used in the @emph{lexical scope} of a package field definition, this
5935 identifier resolves to the package being defined.
5937 The example below shows how to add a package as a native input of itself when
5945 ;; When cross-compiled, Guile, for example, depends on
5946 ;; a native version of itself. Add it here.
5947 (native-inputs (if (%current-target-system)
5948 `(("self" ,this-package))
5952 It is an error to refer to @code{this-package} outside a package definition.
5955 @node origin Reference
5956 @subsection @code{origin} Reference
5958 This section summarizes all the options available in @code{origin}
5959 declarations (@pxref{Defining Packages}).
5961 @deftp {Data Type} origin
5962 This is the data type representing a source code origin.
5966 An object containing the URI of the source. The object type depends on
5967 the @code{method} (see below). For example, when using the
5968 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5969 values are: a URL represented as a string, or a list thereof.
5972 A procedure that handles the URI.
5977 @item @var{url-fetch} from @code{(guix download)}
5978 download a file from the HTTP, HTTPS, or FTP URL specified in the
5982 @item @var{git-fetch} from @code{(guix git-download)}
5983 clone the Git version control repository, and check out the revision
5984 specified in the @code{uri} field as a @code{git-reference} object; a
5985 @code{git-reference} looks like this:
5989 (url "https://git.savannah.gnu.org/git/hello.git")
5995 A bytevector containing the SHA-256 hash of the source. This is
5996 equivalent to providing a @code{content-hash} SHA256 object in the
5997 @code{hash} field described below.
6000 The @code{content-hash} object of the source---see below for how to use
6001 @code{content-hash}.
6003 You can obtain this information using @code{guix download}
6004 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6007 @item @code{file-name} (default: @code{#f})
6008 The file name under which the source code should be saved. When this is
6009 @code{#f}, a sensible default value will be used in most cases. In case
6010 the source is fetched from a URL, the file name from the URL will be
6011 used. For version control checkouts, it is recommended to provide the
6012 file name explicitly because the default is not very descriptive.
6014 @item @code{patches} (default: @code{'()})
6015 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6016 file-like objects}) pointing to patches to be applied to the source.
6018 This list of patches must be unconditional. In particular, it cannot
6019 depend on the value of @code{%current-system} or
6020 @code{%current-target-system}.
6022 @item @code{snippet} (default: @code{#f})
6023 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6024 in the source directory. This is a convenient way to modify the source,
6025 sometimes more convenient than a patch.
6027 @item @code{patch-flags} (default: @code{'("-p1")})
6028 A list of command-line flags that should be passed to the @code{patch}
6031 @item @code{patch-inputs} (default: @code{#f})
6032 Input packages or derivations to the patching process. When this is
6033 @code{#f}, the usual set of inputs necessary for patching are provided,
6034 such as GNU@tie{}Patch.
6036 @item @code{modules} (default: @code{'()})
6037 A list of Guile modules that should be loaded during the patching
6038 process and while running the code in the @code{snippet} field.
6040 @item @code{patch-guile} (default: @code{#f})
6041 The Guile package that should be used in the patching process. When
6042 this is @code{#f}, a sensible default is used.
6046 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6047 Construct a content hash object for the given @var{algorithm}, and with
6048 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6049 it is @code{sha256}.
6051 @var{value} can be a literal string, in which case it is base32-decoded,
6052 or it can be a bytevector.
6054 The following forms are all equivalent:
6057 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6058 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6060 (content-hash (base32
6061 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6062 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6066 Technically, @code{content-hash} is currently implemented as a macro.
6067 It performs sanity checks at macro-expansion time, when possible, such
6068 as ensuring that @var{value} has the right size for @var{algorithm}.
6072 @section Build Systems
6074 @cindex build system
6075 Each package definition specifies a @dfn{build system} and arguments for
6076 that build system (@pxref{Defining Packages}). This @code{build-system}
6077 field represents the build procedure of the package, as well as implicit
6078 dependencies of that build procedure.
6080 Build systems are @code{<build-system>} objects. The interface to
6081 create and manipulate them is provided by the @code{(guix build-system)}
6082 module, and actual build systems are exported by specific modules.
6084 @cindex bag (low-level package representation)
6085 Under the hood, build systems first compile package objects to
6086 @dfn{bags}. A @dfn{bag} is like a package, but with less
6087 ornamentation---in other words, a bag is a lower-level representation of
6088 a package, which includes all the inputs of that package, including some
6089 that were implicitly added by the build system. This intermediate
6090 representation is then compiled to a derivation (@pxref{Derivations}).
6092 Build systems accept an optional list of @dfn{arguments}. In package
6093 definitions, these are passed @i{via} the @code{arguments} field
6094 (@pxref{Defining Packages}). They are typically keyword arguments
6095 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
6096 Guile Reference Manual}). The value of these arguments is usually
6097 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
6098 by the daemon (@pxref{Derivations}).
6100 The main build system is @code{gnu-build-system}, which implements the
6101 standard build procedure for GNU and many other packages. It
6102 is provided by the @code{(guix build-system gnu)} module.
6104 @defvr {Scheme Variable} gnu-build-system
6105 @code{gnu-build-system} represents the GNU Build System, and variants
6106 thereof (@pxref{Configuration, configuration and makefile conventions,,
6107 standards, GNU Coding Standards}).
6109 @cindex build phases
6110 In a nutshell, packages using it are configured, built, and installed with
6111 the usual @code{./configure && make && make check && make install}
6112 command sequence. In practice, a few additional steps are often needed.
6113 All these steps are split up in separate @dfn{phases},
6114 notably@footnote{Please see the @code{(guix build gnu-build-system)}
6115 modules for more details about the build phases.}:
6119 Unpack the source tarball, and change the current directory to the
6120 extracted source tree. If the source is actually a directory, copy it
6121 to the build tree, and enter that directory.
6123 @item patch-source-shebangs
6124 Patch shebangs encountered in source files so they refer to the right
6125 store file names. For instance, this changes @code{#!/bin/sh} to
6126 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
6129 Run the @file{configure} script with a number of default options, such
6130 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
6131 by the @code{#:configure-flags} argument.
6134 Run @code{make} with the list of flags specified with
6135 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
6136 (the default), build with @code{make -j}.
6139 Run @code{make check}, or some other target specified with
6140 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
6141 @code{#:parallel-tests?} argument is true (the default), run @code{make
6145 Run @code{make install} with the flags listed in @code{#:make-flags}.
6147 @item patch-shebangs
6148 Patch shebangs on the installed executable files.
6151 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
6152 is false), copying them to the @code{debug} output when available
6153 (@pxref{Installing Debugging Files}).
6156 @vindex %standard-phases
6157 The build-side module @code{(guix build gnu-build-system)} defines
6158 @code{%standard-phases} as the default list of build phases.
6159 @code{%standard-phases} is a list of symbol/procedure pairs, where the
6160 procedure implements the actual phase.
6162 The list of phases used for a particular package can be changed with the
6163 @code{#:phases} parameter. For instance, passing:
6166 #:phases (modify-phases %standard-phases (delete 'configure))
6169 means that all the phases described above will be used, except the
6170 @code{configure} phase.
6172 In addition, this build system ensures that the ``standard'' environment
6173 for GNU packages is available. This includes tools such as GCC, libc,
6174 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
6175 build-system gnu)} module for a complete list). We call these the
6176 @dfn{implicit inputs} of a package, because package definitions do not
6177 have to mention them.
6180 Other @code{<build-system>} objects are defined to support other
6181 conventions and tools used by free software packages. They inherit most
6182 of @code{gnu-build-system}, and differ mainly in the set of inputs
6183 implicitly added to the build process, and in the list of phases
6184 executed. Some of these build systems are listed below.
6186 @defvr {Scheme Variable} ant-build-system
6187 This variable is exported by @code{(guix build-system ant)}. It
6188 implements the build procedure for Java packages that can be built with
6189 @url{https://ant.apache.org/, Ant build tool}.
6191 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
6192 provided by the @code{icedtea} package to the set of inputs. Different
6193 packages can be specified with the @code{#:ant} and @code{#:jdk}
6194 parameters, respectively.
6196 When the original package does not provide a suitable Ant build file,
6197 the parameter @code{#:jar-name} can be used to generate a minimal Ant
6198 build file @file{build.xml} with tasks to build the specified jar
6199 archive. In this case the parameter @code{#:source-dir} can be used to
6200 specify the source sub-directory, defaulting to ``src''.
6202 The @code{#:main-class} parameter can be used with the minimal ant
6203 buildfile to specify the main class of the resulting jar. This makes the
6204 jar file executable. The @code{#:test-include} parameter can be used to
6205 specify the list of junit tests to run. It defaults to
6206 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
6207 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
6208 because abstract classes cannot be run as tests.
6210 The parameter @code{#:build-target} can be used to specify the Ant task
6211 that should be run during the @code{build} phase. By default the
6212 ``jar'' task will be run.
6216 @defvr {Scheme Variable} android-ndk-build-system
6217 @cindex Android distribution
6218 @cindex Android NDK build system
6219 This variable is exported by @code{(guix build-system android-ndk)}. It
6220 implements a build procedure for Android NDK (native development kit)
6221 packages using a Guix-specific build process.
6223 The build system assumes that packages install their public interface
6224 (header) files to the subdirectory @file{include} of the @code{out} output and
6225 their libraries to the subdirectory @file{lib} the @code{out} output.
6227 It's also assumed that the union of all the dependencies of a package
6228 has no conflicting files.
6230 For the time being, cross-compilation is not supported - so right now
6231 the libraries and header files are assumed to be host tools.
6235 @defvr {Scheme Variable} asdf-build-system/source
6236 @defvrx {Scheme Variable} asdf-build-system/sbcl
6237 @defvrx {Scheme Variable} asdf-build-system/ecl
6239 These variables, exported by @code{(guix build-system asdf)}, implement
6240 build procedures for Common Lisp packages using
6241 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
6242 definition facility for Common Lisp programs and libraries.
6244 The @code{asdf-build-system/source} system installs the packages in
6245 source form, and can be loaded using any common lisp implementation, via
6246 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
6247 systems in the format which a particular implementation understands.
6248 These build systems can also be used to produce executable programs, or
6249 lisp images which contain a set of packages pre-loaded.
6251 The build system uses naming conventions. For binary packages, the
6252 package name should be prefixed with the lisp implementation, such as
6253 @code{sbcl-} for @code{asdf-build-system/sbcl}.
6255 Additionally, the corresponding source package should be labeled using
6256 the same convention as python packages (see @ref{Python Modules}), using
6257 the @code{cl-} prefix.
6259 For binary packages, each system should be defined as a Guix package.
6260 If one package @code{origin} contains several systems, package variants
6261 can be created in order to build all the systems. Source packages,
6262 which use @code{asdf-build-system/source}, may contain several systems.
6264 In order to create executable programs and images, the build-side
6265 procedures @code{build-program} and @code{build-image} can be used.
6266 They should be called in a build phase after the @code{create-symlinks}
6267 phase, so that the system which was just built can be used within the
6268 resulting image. @code{build-program} requires a list of Common Lisp
6269 expressions to be passed as the @code{#:entry-program} argument.
6271 If the system is not defined within its own @file{.asd} file of the same
6272 name, then the @code{#:asd-file} parameter should be used to specify
6273 which file the system is defined in. Furthermore, if the package
6274 defines a system for its tests in a separate file, it will be loaded
6275 before the tests are run if it is specified by the
6276 @code{#:test-asd-file} parameter. If it is not set, the files
6277 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
6278 and @code{test.asd} will be tried if they exist.
6280 If for some reason the package must be named in a different way than the
6281 naming conventions suggest, the @code{#:asd-system-name} parameter can
6282 be used to specify the name of the system.
6286 @defvr {Scheme Variable} cargo-build-system
6287 @cindex Rust programming language
6288 @cindex Cargo (Rust build system)
6289 This variable is exported by @code{(guix build-system cargo)}. It
6290 supports builds of packages using Cargo, the build tool of the
6291 @uref{https://www.rust-lang.org, Rust programming language}.
6293 It adds @code{rustc} and @code{cargo} to the set of inputs.
6294 A different Rust package can be specified with the @code{#:rust} parameter.
6296 Regular cargo dependencies should be added to the package definition via the
6297 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
6298 spec can be a package or a source definition. Note that the spec must
6299 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
6300 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
6301 should be added to the package definition via the
6302 @code{#:cargo-development-inputs} parameter.
6304 In its @code{configure} phase, this build system will make any source inputs
6305 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6306 parameters available to cargo. It will also remove an included
6307 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6308 @code{build} phase. The @code{install} phase installs any crate the binaries
6309 if they are defined by the crate.
6313 @defvr {Scheme Variable} copy-build-system
6314 This variable is exported by @code{(guix build-system copy)}. It
6315 supports builds of simple packages that don't require much compiling,
6316 mostly just moving files around.
6318 It adds much of the @code{gnu-build-system} packages to the set of
6319 inputs. Because of this, the @code{copy-build-system} does not require
6320 all the boilerplate code often needed for the
6321 @code{trivial-build-system}.
6323 To further simplify the file installation process, an
6324 @code{#:install-plan} argument is exposed to let the packager specify
6325 which files go where. The install plan is a list of @code{(@var{source}
6326 @var{target} [@var{filters}])}. @var{filters} are optional.
6329 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
6331 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
6332 @item Otherwise install @var{source} as @var{target}.
6335 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
6336 the trailing slash of @var{target} is implied with the same meaning
6339 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
6340 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
6341 @code{#:exclude-regexp}, only select files are installed depending on
6342 the filters. Each filters is specified by a list of strings.
6344 @item With @code{#:include}, install all the files which the path suffix matches
6345 at least one of the elements in the given list.
6346 @item With @code{#:include-regexp}, install all the files which the
6347 subpaths match at least one of the regular expressions in the given
6349 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
6350 are the complement of their inclusion counterpart. Without @code{#:include} flags,
6351 install all files but those matching the exclusion filters.
6352 If both inclusions and exclusions are specified, the exclusions are done
6353 on top of the inclusions.
6356 In all cases, the paths relative to @var{source} are preserved within
6363 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
6364 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
6365 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
6366 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
6367 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
6368 @file{share/my-app/sub/file}.
6369 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
6370 @file{share/my-app/file}.
6375 @cindex Clojure (programming language)
6376 @cindex simple Clojure build system
6377 @defvr {Scheme Variable} clojure-build-system
6378 This variable is exported by @code{(guix build-system clojure)}. It implements
6379 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6380 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6383 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6384 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6385 @code{#:zip} parameters, respectively.
6387 A list of source directories, test directories and jar names can be specified
6388 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6389 parameters, respectively. Compile directory and main class can be specified
6390 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6391 Other parameters are documented below.
6393 This build system is an extension of @code{ant-build-system}, but with the
6394 following phases changed:
6399 This phase calls @code{compile} in Clojure to compile source files and runs
6400 @command{jar} to create jars from both source files and compiled files
6401 according to the include list and exclude list specified in
6402 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6403 has priority over the include list. These lists consist of symbols
6404 representing Clojure libraries or the special keyword @code{#:all} representing
6405 all Clojure libraries found under the source directories. The parameter
6406 @code{#:omit-source?} decides if source should be included into the jars.
6409 This phase runs tests according to the include list and exclude list specified
6410 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6411 meanings are analogous to that of @code{#:aot-include} and
6412 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6413 stands for all Clojure libraries found under the test directories. The
6414 parameter @code{#:tests?} decides if tests should be run.
6417 This phase installs all jars built previously.
6420 Apart from the above, this build system also contains an additional phase:
6425 This phase installs all top-level files with base name matching
6426 @code{%doc-regex}. A different regex can be specified with the
6427 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6428 directories specified in @code{#:doc-dirs} are installed as well.
6432 @defvr {Scheme Variable} cmake-build-system
6433 This variable is exported by @code{(guix build-system cmake)}. It
6434 implements the build procedure for packages using the
6435 @url{https://www.cmake.org, CMake build tool}.
6437 It automatically adds the @code{cmake} package to the set of inputs.
6438 Which package is used can be specified with the @code{#:cmake}
6441 The @code{#:configure-flags} parameter is taken as a list of flags
6442 passed to the @command{cmake} command. The @code{#:build-type}
6443 parameter specifies in abstract terms the flags passed to the compiler;
6444 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6445 debugging information''), which roughly means that code is compiled with
6446 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6449 @defvr {Scheme Variable} dune-build-system
6450 This variable is exported by @code{(guix build-system dune)}. It
6451 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6452 tool for the OCaml programming language. It is implemented as an extension
6453 of the @code{ocaml-build-system} which is described below. As such, the
6454 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6457 It automatically adds the @code{dune} package to the set of inputs.
6458 Which package is used can be specified with the @code{#:dune}
6461 There is no @code{configure} phase because dune packages typically don't
6462 need to be configured. The @code{#:build-flags} parameter is taken as a
6463 list of flags passed to the @code{dune} command during the build.
6465 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6466 command instead of the more recent @code{dune} command while building
6467 a package. Its default value is @code{#f}.
6469 The @code{#:package} parameter can be passed to specify a package name, which
6470 is useful when a package contains multiple packages and you want to build
6471 only one of them. This is equivalent to passing the @code{-p} argument to
6475 @defvr {Scheme Variable} go-build-system
6476 This variable is exported by @code{(guix build-system go)}. It
6477 implements a build procedure for Go packages using the standard
6478 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6479 Go build mechanisms}.
6481 The user is expected to provide a value for the key @code{#:import-path}
6482 and, in some cases, @code{#:unpack-path}. The
6483 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6484 corresponds to the file system path expected by the package's build
6485 scripts and any referring packages, and provides a unique way to
6486 refer to a Go package. It is typically based on a combination of the
6487 package source code's remote URI and file system hierarchy structure. In
6488 some cases, you will need to unpack the package's source code to a
6489 different directory structure than the one indicated by the import path,
6490 and @code{#:unpack-path} should be used in such cases.
6492 Packages that provide Go libraries should install their source code into
6493 the built output. The key @code{#:install-source?}, which defaults to
6494 @code{#t}, controls whether or not the source code is installed. It can
6495 be set to @code{#f} for packages that only provide executable files.
6498 @defvr {Scheme Variable} glib-or-gtk-build-system
6499 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6500 is intended for use with packages making use of GLib or GTK+.
6502 This build system adds the following two phases to the ones defined by
6503 @code{gnu-build-system}:
6506 @item glib-or-gtk-wrap
6507 The phase @code{glib-or-gtk-wrap} ensures that programs in
6508 @file{bin/} are able to find GLib ``schemas'' and
6509 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6510 modules}. This is achieved by wrapping the programs in launch scripts
6511 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
6512 environment variables.
6514 It is possible to exclude specific package outputs from that wrapping
6515 process by listing their names in the
6516 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6517 when an output is known not to contain any GLib or GTK+ binaries, and
6518 where wrapping would gratuitously add a dependency of that output on
6521 @item glib-or-gtk-compile-schemas
6522 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6523 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6524 GSettings schemas} of GLib are compiled. Compilation is performed by the
6525 @command{glib-compile-schemas} program. It is provided by the package
6526 @code{glib:bin} which is automatically imported by the build system.
6527 The @code{glib} package providing @command{glib-compile-schemas} can be
6528 specified with the @code{#:glib} parameter.
6531 Both phases are executed after the @code{install} phase.
6534 @defvr {Scheme Variable} guile-build-system
6535 This build system is for Guile packages that consist exclusively of Scheme
6536 code and that are so lean that they don't even have a makefile, let alone a
6537 @file{configure} script. It compiles Scheme code using @command{guild
6538 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6539 installs the @file{.scm} and @file{.go} files in the right place. It also
6540 installs documentation.
6542 This build system supports cross-compilation by using the
6543 @option{--target} option of @samp{guild compile}.
6545 Packages built with @code{guile-build-system} must provide a Guile package in
6546 their @code{native-inputs} field.
6549 @defvr {Scheme Variable} julia-build-system
6550 This variable is exported by @code{(guix build-system julia)}. It
6551 implements the build procedure used by @uref{https://julialang.org/,
6552 julia} packages, which essentially is similar to running @samp{julia -e
6553 'using Pkg; Pkg.add(package)'} in an environment where
6554 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
6555 Tests are run not run.
6557 Julia packages require the source @code{file-name} to be the real name of the
6558 package, correctly capitalized.
6560 For packages requiring shared library dependencies, you may need to write the
6561 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6562 variable = /gnu/store/library.so} for each dependency, plus a void function
6563 @code{check_deps() = nothing}.
6565 Some older packages that aren't using @file{Package.toml} yet, will require
6566 this file to be created, too. The function @code{julia-create-package-toml}
6567 helps creating the file. You need to pass the outputs and the source of the
6568 package, it's name (the same as the @code{file-name} parameter), the package
6569 uuid, the package version, and a list of dependencies specified by their name
6573 @defvr {Scheme Variable} minify-build-system
6574 This variable is exported by @code{(guix build-system minify)}. It
6575 implements a minification procedure for simple JavaScript packages.
6577 It adds @code{uglify-js} to the set of inputs and uses it to compress
6578 all JavaScript files in the @file{src} directory. A different minifier
6579 package can be specified with the @code{#:uglify-js} parameter, but it
6580 is expected that the package writes the minified code to the standard
6583 When the input JavaScript files are not all located in the @file{src}
6584 directory, the parameter @code{#:javascript-files} can be used to
6585 specify a list of file names to feed to the minifier.
6588 @defvr {Scheme Variable} ocaml-build-system
6589 This variable is exported by @code{(guix build-system ocaml)}. It implements
6590 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6591 of choosing the correct set of commands to run for each package. OCaml
6592 packages can expect many different commands to be run. This build system will
6595 When the package has a @file{setup.ml} file present at the top-level, it will
6596 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6597 @code{ocaml setup.ml -install}. The build system will assume that this file
6598 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6599 care of setting the prefix and enabling tests if they are not disabled. You
6600 can pass configure and build flags with the @code{#:configure-flags} and
6601 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6602 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6603 bypass this system in the build and install phases.
6605 When the package has a @file{configure} file, it is assumed that it is a
6606 hand-made configure script that requires a different argument format than
6607 in the @code{gnu-build-system}. You can add more flags with the
6608 @code{#:configure-flags} key.
6610 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6611 @code{#t}), it will be used and more flags can be passed to the build and
6612 install phases with the @code{#:make-flags} key.
6614 Finally, some packages do not have these files and use a somewhat standard
6615 location for its build system. In that case, the build system will run
6616 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6617 providing the path to the required findlib module. Additional flags can
6618 be passed via the @code{#:build-flags} key. Install is taken care of by
6619 @command{opam-installer}. In this case, the @code{opam} package must
6620 be added to the @code{native-inputs} field of the package definition.
6622 Note that most OCaml packages assume they will be installed in the same
6623 directory as OCaml, which is not what we want in guix. In particular, they
6624 will install @file{.so} files in their module's directory, which is usually
6625 fine because it is in the OCaml compiler directory. In guix though, these
6626 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
6627 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6628 @file{.so} libraries should be installed.
6631 @defvr {Scheme Variable} python-build-system
6632 This variable is exported by @code{(guix build-system python)}. It
6633 implements the more or less standard build procedure used by Python
6634 packages, which consists in running @code{python setup.py build} and
6635 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6637 For packages that install stand-alone Python programs under @code{bin/},
6638 it takes care of wrapping these programs so that their @env{PYTHONPATH}
6639 environment variable points to all the Python libraries they depend on.
6641 Which Python package is used to perform the build can be specified with
6642 the @code{#:python} parameter. This is a useful way to force a package
6643 to be built for a specific version of the Python interpreter, which
6644 might be necessary if the package is only compatible with a single
6645 interpreter version.
6647 By default guix calls @code{setup.py} under control of
6648 @code{setuptools}, much like @command{pip} does. Some packages are not
6649 compatible with setuptools (and pip), thus you can disable this by
6650 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6653 @defvr {Scheme Variable} perl-build-system
6654 This variable is exported by @code{(guix build-system perl)}. It
6655 implements the standard build procedure for Perl packages, which either
6656 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6657 followed by @code{Build} and @code{Build install}; or in running
6658 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6659 @code{make} and @code{make install}, depending on which of
6660 @code{Build.PL} or @code{Makefile.PL} is present in the package
6661 distribution. Preference is given to the former if both @code{Build.PL}
6662 and @code{Makefile.PL} exist in the package distribution. This
6663 preference can be reversed by specifying @code{#t} for the
6664 @code{#:make-maker?} parameter.
6666 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6667 passes flags specified by the @code{#:make-maker-flags} or
6668 @code{#:module-build-flags} parameter, respectively.
6670 Which Perl package is used can be specified with @code{#:perl}.
6673 @defvr {Scheme Variable} qt-build-system
6674 This variable is exported by @code{(guix build-system qt)}. It
6675 is intended for use with applications using Qt or KDE.
6677 This build system adds the following two phases to the ones defined by
6678 @code{cmake-build-system}:
6682 The phase @code{check-setup} prepares the environment for running
6683 the checks as commonly used by Qt test programs.
6684 For now this only sets some environment variables:
6685 @code{QT_QPA_PLATFORM=offscreen},
6686 @code{DBUS_FATAL_WARNINGS=0} and
6687 @code{CTEST_OUTPUT_ON_FAILURE=1}.
6689 This phase is added before the @code{check} phase.
6690 It's a separate phase to ease adjusting if necessary.
6693 The phase @code{qt-wrap}
6694 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
6695 and output. In case some path is found, all programs in the output's
6696 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
6697 are wrapped in scripts defining the necessary environment variables.
6699 It is possible to exclude specific package outputs from that wrapping process
6700 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
6701 This is useful when an output is known not to contain any Qt binaries, and
6702 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
6705 This phase is added after the @code{install} phase.
6709 @defvr {Scheme Variable} r-build-system
6710 This variable is exported by @code{(guix build-system r)}. It
6711 implements the build procedure used by @uref{https://r-project.org, R}
6712 packages, which essentially is little more than running @samp{R CMD
6713 INSTALL --library=/gnu/store/@dots{}} in an environment where
6714 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
6715 run after installation using the R function
6716 @code{tools::testInstalledPackage}.
6719 @defvr {Scheme Variable} rakudo-build-system
6720 This variable is exported by @code{(guix build-system rakudo)}. It
6721 implements the build procedure used by @uref{https://rakudo.org/,
6722 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6723 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6724 installs the binaries, library files and the resources, as well as wrap
6725 the files under the @code{bin/} directory. Tests can be skipped by
6726 passing @code{#f} to the @code{tests?} parameter.
6728 Which rakudo package is used can be specified with @code{rakudo}.
6729 Which perl6-tap-harness package used for the tests can be specified with
6730 @code{#:prove6} or removed by passing @code{#f} to the
6731 @code{with-prove6?} parameter.
6732 Which perl6-zef package used for tests and installing can be specified
6733 with @code{#:zef} or removed by passing @code{#f} to the
6734 @code{with-zef?} parameter.
6737 @defvr {Scheme Variable} texlive-build-system
6738 This variable is exported by @code{(guix build-system texlive)}. It is
6739 used to build TeX packages in batch mode with a specified engine. The
6740 build system sets the @env{TEXINPUTS} variable to find all TeX source
6741 files in the inputs.
6743 By default it runs @code{luatex} on all files ending on @code{ins}. A
6744 different engine and format can be specified with the
6745 @code{#:tex-format} argument. Different build targets can be specified
6746 with the @code{#:build-targets} argument, which expects a list of file
6747 names. The build system adds only @code{texlive-bin} and
6748 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6749 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6750 and @code{#:texlive-latex-base}, respectively.
6752 The @code{#:tex-directory} parameter tells the build system where to
6753 install the built files under the texmf tree.
6756 @defvr {Scheme Variable} ruby-build-system
6757 This variable is exported by @code{(guix build-system ruby)}. It
6758 implements the RubyGems build procedure used by Ruby packages, which
6759 involves running @code{gem build} followed by @code{gem install}.
6761 The @code{source} field of a package that uses this build system
6762 typically references a gem archive, since this is the format that Ruby
6763 developers use when releasing their software. The build system unpacks
6764 the gem archive, potentially patches the source, runs the test suite,
6765 repackages the gem, and installs it. Additionally, directories and
6766 tarballs may be referenced to allow building unreleased gems from Git or
6767 a traditional source release tarball.
6769 Which Ruby package is used can be specified with the @code{#:ruby}
6770 parameter. A list of additional flags to be passed to the @command{gem}
6771 command can be specified with the @code{#:gem-flags} parameter.
6774 @defvr {Scheme Variable} waf-build-system
6775 This variable is exported by @code{(guix build-system waf)}. It
6776 implements a build procedure around the @code{waf} script. The common
6777 phases---@code{configure}, @code{build}, and @code{install}---are
6778 implemented by passing their names as arguments to the @code{waf}
6781 The @code{waf} script is executed by the Python interpreter. Which
6782 Python package is used to run the script can be specified with the
6783 @code{#:python} parameter.
6786 @defvr {Scheme Variable} scons-build-system
6787 This variable is exported by @code{(guix build-system scons)}. It
6788 implements the build procedure used by the SCons software construction
6789 tool. This build system runs @code{scons} to build the package,
6790 @code{scons test} to run tests, and then @code{scons install} to install
6793 Additional flags to be passed to @code{scons} can be specified with the
6794 @code{#:scons-flags} parameter. The default build and install targets
6795 can be overridden with @code{#:build-targets} and
6796 @code{#:install-targets} respectively. The version of Python used to
6797 run SCons can be specified by selecting the appropriate SCons package
6798 with the @code{#:scons} parameter.
6801 @defvr {Scheme Variable} haskell-build-system
6802 This variable is exported by @code{(guix build-system haskell)}. It
6803 implements the Cabal build procedure used by Haskell packages, which
6804 involves running @code{runhaskell Setup.hs configure
6805 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6806 Instead of installing the package by running @code{runhaskell Setup.hs
6807 install}, to avoid trying to register libraries in the read-only
6808 compiler store directory, the build system uses @code{runhaskell
6809 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6810 addition, the build system generates the package documentation by
6811 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6812 is passed. Optional Haddock parameters can be passed with the help of
6813 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6814 not found, the build system looks for @code{Setup.lhs} instead.
6816 Which Haskell compiler is used can be specified with the @code{#:haskell}
6817 parameter which defaults to @code{ghc}.
6820 @defvr {Scheme Variable} dub-build-system
6821 This variable is exported by @code{(guix build-system dub)}. It
6822 implements the Dub build procedure used by D packages, which
6823 involves running @code{dub build} and @code{dub run}.
6824 Installation is done by copying the files manually.
6826 Which D compiler is used can be specified with the @code{#:ldc}
6827 parameter which defaults to @code{ldc}.
6830 @defvr {Scheme Variable} emacs-build-system
6831 This variable is exported by @code{(guix build-system emacs)}. It
6832 implements an installation procedure similar to the packaging system
6833 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6835 It first creates the @code{@code{package}-autoloads.el} file, then it
6836 byte compiles all Emacs Lisp files. Differently from the Emacs
6837 packaging system, the Info documentation files are moved to the standard
6838 documentation directory and the @file{dir} file is deleted. The Elisp
6839 package files are installed directly under @file{share/emacs/site-lisp}.
6842 @defvr {Scheme Variable} font-build-system
6843 This variable is exported by @code{(guix build-system font)}. It
6844 implements an installation procedure for font packages where upstream
6845 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6846 need to be copied into place. It copies font files to standard
6847 locations in the output directory.
6850 @defvr {Scheme Variable} meson-build-system
6851 This variable is exported by @code{(guix build-system meson)}. It
6852 implements the build procedure for packages that use
6853 @url{https://mesonbuild.com, Meson} as their build system.
6855 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6856 of inputs, and they can be changed with the parameters @code{#:meson}
6857 and @code{#:ninja} if needed. The default Meson is
6858 @code{meson-for-build}, which is special because it doesn't clear the
6859 @code{RUNPATH} of binaries and libraries when they are installed.
6861 This build system is an extension of @code{gnu-build-system}, but with the
6862 following phases changed to some specific for Meson:
6867 The phase runs @code{meson} with the flags specified in
6868 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
6869 @code{debugoptimized} unless something else is specified in
6870 @code{#:build-type}.
6873 The phase runs @code{ninja} to build the package in parallel by default, but
6874 this can be changed with @code{#:parallel-build?}.
6877 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6878 which is @code{"test"} by default.
6881 The phase runs @code{ninja install} and can not be changed.
6884 Apart from that, the build system also adds the following phases:
6889 This phase ensures that all binaries can find the libraries they need.
6890 It searches for required libraries in subdirectories of the package being
6891 built, and adds those to @code{RUNPATH} where needed. It also removes
6892 references to libraries left over from the build phase by
6893 @code{meson-for-build}, such as test dependencies, that aren't actually
6894 required for the program to run.
6896 @item glib-or-gtk-wrap
6897 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6898 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6900 @item glib-or-gtk-compile-schemas
6901 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6902 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6906 @defvr {Scheme Variable} linux-module-build-system
6907 @code{linux-module-build-system} allows building Linux kernel modules.
6909 @cindex build phases
6910 This build system is an extension of @code{gnu-build-system}, but with the
6911 following phases changed:
6916 This phase configures the environment so that the Linux kernel's Makefile
6917 can be used to build the external kernel module.
6920 This phase uses the Linux kernel's Makefile in order to build the external
6924 This phase uses the Linux kernel's Makefile in order to install the external
6928 It is possible and useful to specify the Linux kernel to use for building
6929 the module (in the @code{arguments} form of a package using the
6930 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
6933 @defvr {Scheme Variable} node-build-system
6934 This variable is exported by @code{(guix build-system node)}. It
6935 implements the build procedure used by @uref{https://nodejs.org,
6936 Node.js}, which implements an approximation of the @code{npm install}
6937 command, followed by an @code{npm test} command.
6939 Which Node.js package is used to interpret the @code{npm} commands can
6940 be specified with the @code{#:node} parameter which defaults to
6944 Lastly, for packages that do not need anything as sophisticated, a
6945 ``trivial'' build system is provided. It is trivial in the sense that
6946 it provides basically no support: it does not pull any implicit inputs,
6947 and does not have a notion of build phases.
6949 @defvr {Scheme Variable} trivial-build-system
6950 This variable is exported by @code{(guix build-system trivial)}.
6952 This build system requires a @code{#:builder} argument. This argument
6953 must be a Scheme expression that builds the package output(s)---as
6954 with @code{build-expression->derivation} (@pxref{Derivations,
6955 @code{build-expression->derivation}}).
6965 Conceptually, the @dfn{store} is the place where derivations that have
6966 been built successfully are stored---by default, @file{/gnu/store}.
6967 Sub-directories in the store are referred to as @dfn{store items} or
6968 sometimes @dfn{store paths}. The store has an associated database that
6969 contains information such as the store paths referred to by each store
6970 path, and the list of @emph{valid} store items---results of successful
6971 builds. This database resides in @file{@var{localstatedir}/guix/db},
6972 where @var{localstatedir} is the state directory specified @i{via}
6973 @option{--localstatedir} at configure time, usually @file{/var}.
6975 The store is @emph{always} accessed by the daemon on behalf of its clients
6976 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6977 connect to the daemon over a Unix-domain socket, send requests to it,
6978 and read the result---these are remote procedure calls, or RPCs.
6981 Users must @emph{never} modify files under @file{/gnu/store} directly.
6982 This would lead to inconsistencies and break the immutability
6983 assumptions of Guix's functional model (@pxref{Introduction}).
6985 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6986 how to check the integrity of the store and attempt recovery from
6987 accidental modifications.
6990 The @code{(guix store)} module provides procedures to connect to the
6991 daemon, and to perform RPCs. These are described below. By default,
6992 @code{open-connection}, and thus all the @command{guix} commands,
6993 connect to the local daemon or to the URI specified by the
6994 @env{GUIX_DAEMON_SOCKET} environment variable.
6996 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6997 When set, the value of this variable should be a file name or a URI
6998 designating the daemon endpoint. When it is a file name, it denotes a
6999 Unix-domain socket to connect to. In addition to file names, the
7000 supported URI schemes are:
7005 These are for Unix-domain sockets.
7006 @code{file:///var/guix/daemon-socket/socket} is equivalent to
7007 @file{/var/guix/daemon-socket/socket}.
7010 @cindex daemon, remote access
7011 @cindex remote access to the daemon
7012 @cindex daemon, cluster setup
7013 @cindex clusters, daemon setup
7014 These URIs denote connections over TCP/IP, without encryption nor
7015 authentication of the remote host. The URI must specify the host name
7016 and optionally a port number (by default port 44146 is used):
7019 guix://master.guix.example.org:1234
7022 This setup is suitable on local networks, such as clusters, where only
7023 trusted nodes may connect to the build daemon at
7024 @code{master.guix.example.org}.
7026 The @option{--listen} option of @command{guix-daemon} can be used to
7027 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
7028 @option{--listen}}).
7031 @cindex SSH access to build daemons
7032 These URIs allow you to connect to a remote daemon over SSH. This
7033 feature requires Guile-SSH (@pxref{Requirements}) and a working
7034 @command{guile} binary in @env{PATH} on the destination machine. It
7035 supports public key and GSSAPI authentication. A typical URL might look
7039 ssh://charlie@@guix.example.org:22
7042 As for @command{guix copy}, the usual OpenSSH client configuration files
7043 are honored (@pxref{Invoking guix copy}).
7046 Additional URI schemes may be supported in the future.
7048 @c XXX: Remove this note when the protocol incurs fewer round trips
7049 @c and when (guix derivations) no longer relies on file system access.
7051 The ability to connect to remote build daemons is considered
7052 experimental as of @value{VERSION}. Please get in touch with us to
7053 share any problems or suggestions you may have (@pxref{Contributing}).
7057 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
7058 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
7059 @var{reserve-space?} is true, instruct it to reserve a little bit of
7060 extra space on the file system so that the garbage collector can still
7061 operate should the disk become full. Return a server object.
7063 @var{file} defaults to @code{%default-socket-path}, which is the normal
7064 location given the options that were passed to @command{configure}.
7067 @deffn {Scheme Procedure} close-connection @var{server}
7068 Close the connection to @var{server}.
7071 @defvr {Scheme Variable} current-build-output-port
7072 This variable is bound to a SRFI-39 parameter, which refers to the port
7073 where build and error logs sent by the daemon should be written.
7076 Procedures that make RPCs all take a server object as their first
7079 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
7080 @cindex invalid store items
7081 Return @code{#t} when @var{path} designates a valid store item and
7082 @code{#f} otherwise (an invalid item may exist on disk but still be
7083 invalid, for instance because it is the result of an aborted or failed
7086 A @code{&store-protocol-error} condition is raised if @var{path} is not
7087 prefixed by the store directory (@file{/gnu/store}).
7090 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
7091 Add @var{text} under file @var{name} in the store, and return its store
7092 path. @var{references} is the list of store paths referred to by the
7093 resulting store path.
7096 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
7098 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
7099 file names, or derivation/output pairs, using the specified
7100 @var{mode}---@code{(build-mode normal)} by default.
7103 Note that the @code{(guix monads)} module provides a monad as well as
7104 monadic versions of the above procedures, with the goal of making it
7105 more convenient to work with code that accesses the store (@pxref{The
7109 @i{This section is currently incomplete.}
7112 @section Derivations
7115 Low-level build actions and the environment in which they are performed
7116 are represented by @dfn{derivations}. A derivation contains the
7117 following pieces of information:
7121 The outputs of the derivation---derivations produce at least one file or
7122 directory in the store, but may produce more.
7125 @cindex build-time dependencies
7126 @cindex dependencies, build-time
7127 The inputs of the derivations---i.e., its build-time dependencies---which may
7128 be other derivations or plain files in the store (patches, build scripts,
7132 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
7135 The file name of a build script in the store, along with the arguments
7139 A list of environment variables to be defined.
7143 @cindex derivation path
7144 Derivations allow clients of the daemon to communicate build actions to
7145 the store. They exist in two forms: as an in-memory representation,
7146 both on the client- and daemon-side, and as files in the store whose
7147 name end in @file{.drv}---these files are referred to as @dfn{derivation
7148 paths}. Derivations paths can be passed to the @code{build-derivations}
7149 procedure to perform the build actions they prescribe (@pxref{The
7152 @cindex fixed-output derivations
7153 Operations such as file downloads and version-control checkouts for
7154 which the expected content hash is known in advance are modeled as
7155 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
7156 of a fixed-output derivation are independent of its inputs---e.g., a
7157 source code download produces the same result regardless of the download
7158 method and tools being used.
7161 @cindex run-time dependencies
7162 @cindex dependencies, run-time
7163 The outputs of derivations---i.e., the build results---have a set of
7164 @dfn{references}, as reported by the @code{references} RPC or the
7165 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
7166 are the set of run-time dependencies of the build results. References are a
7167 subset of the inputs of the derivation; this subset is automatically computed
7168 by the build daemon by scanning all the files in the outputs.
7170 The @code{(guix derivations)} module provides a representation of
7171 derivations as Scheme objects, along with procedures to create and
7172 otherwise manipulate derivations. The lowest-level primitive to create
7173 a derivation is the @code{derivation} procedure:
7175 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
7176 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7177 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
7178 [#:system (%current-system)] [#:references-graphs #f] @
7179 [#:allowed-references #f] [#:disallowed-references #f] @
7180 [#:leaked-env-vars #f] [#:local-build? #f] @
7181 [#:substitutable? #t] [#:properties '()]
7182 Build a derivation with the given arguments, and return the resulting
7183 @code{<derivation>} object.
7185 When @var{hash} and @var{hash-algo} are given, a
7186 @dfn{fixed-output derivation} is created---i.e., one whose result is
7187 known in advance, such as a file download. If, in addition,
7188 @var{recursive?} is true, then that fixed output may be an executable
7189 file or a directory and @var{hash} must be the hash of an archive
7190 containing this output.
7192 When @var{references-graphs} is true, it must be a list of file
7193 name/store path pairs. In that case, the reference graph of each store
7194 path is exported in the build environment in the corresponding file, in
7195 a simple text format.
7197 When @var{allowed-references} is true, it must be a list of store items
7198 or outputs that the derivation's output may refer to. Likewise,
7199 @var{disallowed-references}, if true, must be a list of things the
7200 outputs may @emph{not} refer to.
7202 When @var{leaked-env-vars} is true, it must be a list of strings
7203 denoting environment variables that are allowed to ``leak'' from the
7204 daemon's environment to the build environment. This is only applicable
7205 to fixed-output derivations---i.e., when @var{hash} is true. The main
7206 use is to allow variables such as @code{http_proxy} to be passed to
7207 derivations that download files.
7209 When @var{local-build?} is true, declare that the derivation is not a
7210 good candidate for offloading and should rather be built locally
7211 (@pxref{Daemon Offload Setup}). This is the case for small derivations
7212 where the costs of data transfers would outweigh the benefits.
7214 When @var{substitutable?} is false, declare that substitutes of the
7215 derivation's output should not be used (@pxref{Substitutes}). This is
7216 useful, for instance, when building packages that capture details of the
7217 host CPU instruction set.
7219 @var{properties} must be an association list describing ``properties'' of the
7220 derivation. It is kept as-is, uninterpreted, in the derivation.
7224 Here's an example with a shell script as its builder, assuming
7225 @var{store} is an open connection to the daemon, and @var{bash} points
7226 to a Bash executable in the store:
7229 (use-modules (guix utils)
7233 (let ((builder ; add the Bash script to the store
7234 (add-text-to-store store "my-builder.sh"
7235 "echo hello world > $out\n" '())))
7236 (derivation store "foo"
7237 bash `("-e" ,builder)
7238 #:inputs `((,bash) (,builder))
7239 #:env-vars '(("HOME" . "/homeless"))))
7240 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
7243 As can be guessed, this primitive is cumbersome to use directly. A
7244 better approach is to write build scripts in Scheme, of course! The
7245 best course of action for that is to write the build code as a
7246 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
7247 information, @pxref{G-Expressions}.
7249 Once upon a time, @code{gexp->derivation} did not exist and constructing
7250 derivations with build code written in Scheme was achieved with
7251 @code{build-expression->derivation}, documented below. This procedure
7252 is now deprecated in favor of the much nicer @code{gexp->derivation}.
7254 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
7255 @var{name} @var{exp} @
7256 [#:system (%current-system)] [#:inputs '()] @
7257 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7258 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7259 [#:references-graphs #f] [#:allowed-references #f] @
7260 [#:disallowed-references #f] @
7261 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
7262 Return a derivation that executes Scheme expression @var{exp} as a
7263 builder for derivation @var{name}. @var{inputs} must be a list of
7264 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
7265 @code{"out"} is assumed. @var{modules} is a list of names of Guile
7266 modules from the current search path to be copied in the store,
7267 compiled, and made available in the load path during the execution of
7268 @var{exp}---e.g., @code{((guix build utils) (guix build
7269 gnu-build-system))}.
7271 @var{exp} is evaluated in an environment where @code{%outputs} is bound
7272 to a list of output/path pairs, and where @code{%build-inputs} is bound
7273 to a list of string/output-path pairs made from @var{inputs}.
7274 Optionally, @var{env-vars} is a list of string pairs specifying the name
7275 and value of environment variables visible to the builder. The builder
7276 terminates by passing the result of @var{exp} to @code{exit}; thus, when
7277 @var{exp} returns @code{#f}, the build is considered to have failed.
7279 @var{exp} is built using @var{guile-for-build} (a derivation). When
7280 @var{guile-for-build} is omitted or is @code{#f}, the value of the
7281 @code{%guile-for-build} fluid is used instead.
7283 See the @code{derivation} procedure for the meaning of
7284 @var{references-graphs}, @var{allowed-references},
7285 @var{disallowed-references}, @var{local-build?}, and
7286 @var{substitutable?}.
7290 Here's an example of a single-output derivation that creates a directory
7291 containing one file:
7294 (let ((builder '(let ((out (assoc-ref %outputs "out")))
7295 (mkdir out) ; create /gnu/store/@dots{}-goo
7296 (call-with-output-file (string-append out "/test")
7298 (display '(hello guix) p))))))
7299 (build-expression->derivation store "goo" builder))
7301 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
7305 @node The Store Monad
7306 @section The Store Monad
7310 The procedures that operate on the store described in the previous
7311 sections all take an open connection to the build daemon as their first
7312 argument. Although the underlying model is functional, they either have
7313 side effects or depend on the current state of the store.
7315 The former is inconvenient: the connection to the build daemon has to be
7316 carried around in all those functions, making it impossible to compose
7317 functions that do not take that parameter with functions that do. The
7318 latter can be problematic: since store operations have side effects
7319 and/or depend on external state, they have to be properly sequenced.
7321 @cindex monadic values
7322 @cindex monadic functions
7323 This is where the @code{(guix monads)} module comes in. This module
7324 provides a framework for working with @dfn{monads}, and a particularly
7325 useful monad for our uses, the @dfn{store monad}. Monads are a
7326 construct that allows two things: associating ``context'' with values
7327 (in our case, the context is the store), and building sequences of
7328 computations (here computations include accesses to the store). Values
7329 in a monad---values that carry this additional context---are called
7330 @dfn{monadic values}; procedures that return such values are called
7331 @dfn{monadic procedures}.
7333 Consider this ``normal'' procedure:
7336 (define (sh-symlink store)
7337 ;; Return a derivation that symlinks the 'bash' executable.
7338 (let* ((drv (package-derivation store bash))
7339 (out (derivation->output-path drv))
7340 (sh (string-append out "/bin/bash")))
7341 (build-expression->derivation store "sh"
7342 `(symlink ,sh %output))))
7345 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
7346 as a monadic function:
7349 (define (sh-symlink)
7350 ;; Same, but return a monadic value.
7351 (mlet %store-monad ((drv (package->derivation bash)))
7352 (gexp->derivation "sh"
7353 #~(symlink (string-append #$drv "/bin/bash")
7357 There are several things to note in the second version: the @code{store}
7358 parameter is now implicit and is ``threaded'' in the calls to the
7359 @code{package->derivation} and @code{gexp->derivation} monadic
7360 procedures, and the monadic value returned by @code{package->derivation}
7361 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
7363 As it turns out, the call to @code{package->derivation} can even be
7364 omitted since it will take place implicitly, as we will see later
7365 (@pxref{G-Expressions}):
7368 (define (sh-symlink)
7369 (gexp->derivation "sh"
7370 #~(symlink (string-append #$bash "/bin/bash")
7375 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
7376 @c for the funny quote.
7377 Calling the monadic @code{sh-symlink} has no effect. As someone once
7378 said, ``you exit a monad like you exit a building on fire: by running''.
7379 So, to exit the monad and get the desired effect, one must use
7380 @code{run-with-store}:
7383 (run-with-store (open-connection) (sh-symlink))
7384 @result{} /gnu/store/...-sh-symlink
7387 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
7388 new ``meta-commands'' to make it easier to deal with monadic procedures:
7389 @code{run-in-store}, and @code{enter-store-monad}. The former is used
7390 to ``run'' a single monadic value through the store:
7393 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
7394 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7397 The latter enters a recursive REPL, where all the return values are
7398 automatically run through the store:
7401 scheme@@(guile-user)> ,enter-store-monad
7402 store-monad@@(guile-user) [1]> (package->derivation hello)
7403 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7404 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
7405 $3 = "/gnu/store/@dots{}-foo"
7406 store-monad@@(guile-user) [1]> ,q
7407 scheme@@(guile-user)>
7411 Note that non-monadic values cannot be returned in the
7412 @code{store-monad} REPL.
7414 The main syntactic forms to deal with monads in general are provided by
7415 the @code{(guix monads)} module and are described below.
7417 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7418 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7422 @deffn {Scheme Syntax} return @var{val}
7423 Return a monadic value that encapsulates @var{val}.
7426 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7427 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7428 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7429 referred to as ``bind'', but that name denotes an unrelated procedure in
7430 Guile. Thus we use this somewhat cryptic symbol inherited from the
7431 Haskell language.}. There can be one @var{mproc} or several of them, as
7436 (with-monad %state-monad
7438 (lambda (x) (return (+ 1 x)))
7439 (lambda (x) (return (* 2 x)))))
7443 @result{} some-state
7447 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7449 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7451 Bind the variables @var{var} to the monadic values @var{mval} in
7452 @var{body}, which is a sequence of expressions. As with the bind
7453 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7454 value ``contained'' in @var{mval} and making @var{var} refer to that
7455 raw, non-monadic value within the scope of the @var{body}. The form
7456 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7457 @var{val}, as per @code{let}. The binding operations occur in sequence
7458 from left to right. The last expression of @var{body} must be a monadic
7459 expression, and its result will become the result of the @code{mlet} or
7460 @code{mlet*} when run in the @var{monad}.
7462 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7463 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7466 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7467 Bind @var{mexp} and the following monadic expressions in sequence,
7468 returning the result of the last expression. Every expression in the
7469 sequence must be a monadic expression.
7471 This is akin to @code{mlet}, except that the return values of the
7472 monadic expressions are ignored. In that sense, it is analogous to
7473 @code{begin}, but applied to monadic expressions.
7476 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7477 When @var{condition} is true, evaluate the sequence of monadic
7478 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7479 @var{condition} is false, return @code{*unspecified*} in the current
7480 monad. Every expression in the sequence must be a monadic expression.
7483 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7484 When @var{condition} is false, evaluate the sequence of monadic
7485 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7486 @var{condition} is true, return @code{*unspecified*} in the current
7487 monad. Every expression in the sequence must be a monadic expression.
7491 The @code{(guix monads)} module provides the @dfn{state monad}, which
7492 allows an additional value---the state---to be @emph{threaded} through
7493 monadic procedure calls.
7495 @defvr {Scheme Variable} %state-monad
7496 The state monad. Procedures in the state monad can access and change
7497 the state that is threaded.
7499 Consider the example below. The @code{square} procedure returns a value
7500 in the state monad. It returns the square of its argument, but also
7501 increments the current state value:
7505 (mlet %state-monad ((count (current-state)))
7506 (mbegin %state-monad
7507 (set-current-state (+ 1 count))
7510 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7515 When ``run'' through @code{%state-monad}, we obtain that additional state
7516 value, which is the number of @code{square} calls.
7519 @deffn {Monadic Procedure} current-state
7520 Return the current state as a monadic value.
7523 @deffn {Monadic Procedure} set-current-state @var{value}
7524 Set the current state to @var{value} and return the previous state as a
7528 @deffn {Monadic Procedure} state-push @var{value}
7529 Push @var{value} to the current state, which is assumed to be a list,
7530 and return the previous state as a monadic value.
7533 @deffn {Monadic Procedure} state-pop
7534 Pop a value from the current state and return it as a monadic value.
7535 The state is assumed to be a list.
7538 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7539 Run monadic value @var{mval} starting with @var{state} as the initial
7540 state. Return two values: the resulting value, and the resulting state.
7543 The main interface to the store monad, provided by the @code{(guix
7544 store)} module, is as follows.
7546 @defvr {Scheme Variable} %store-monad
7547 The store monad---an alias for @code{%state-monad}.
7549 Values in the store monad encapsulate accesses to the store. When its
7550 effect is needed, a value of the store monad must be ``evaluated'' by
7551 passing it to the @code{run-with-store} procedure (see below).
7554 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7555 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7556 open store connection.
7559 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7560 Return as a monadic value the absolute file name in the store of the file
7561 containing @var{text}, a string. @var{references} is a list of store items that the
7562 resulting text file refers to; it defaults to the empty list.
7565 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7566 Return as a monadic value the absolute file name in the store of the file
7567 containing @var{data}, a bytevector. @var{references} is a list of store
7568 items that the resulting binary file refers to; it defaults to the empty list.
7571 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7572 [#:recursive? #t] [#:select? (const #t)]
7573 Return the name of @var{file} once interned in the store. Use
7574 @var{name} as its store name, or the basename of @var{file} if
7575 @var{name} is omitted.
7577 When @var{recursive?} is true, the contents of @var{file} are added
7578 recursively; if @var{file} designates a flat file and @var{recursive?}
7579 is true, its contents are added, and its permission bits are kept.
7581 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7582 @var{stat})} for each directory entry, where @var{file} is the entry's
7583 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7584 entries for which @var{select?} does not return true.
7586 The example below adds a file to the store, under two different names:
7589 (run-with-store (open-connection)
7590 (mlet %store-monad ((a (interned-file "README"))
7591 (b (interned-file "README" "LEGU-MIN")))
7592 (return (list a b))))
7594 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7599 The @code{(guix packages)} module exports the following package-related
7602 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7603 [#:system (%current-system)] [#:target #f] @
7606 value in the absolute file name of @var{file} within the @var{output}
7607 directory of @var{package}. When @var{file} is omitted, return the name
7608 of the @var{output} directory of @var{package}. When @var{target} is
7609 true, use it as a cross-compilation target triplet.
7611 Note that this procedure does @emph{not} build @var{package}. Thus, the
7612 result might or might not designate an existing file. We recommend not
7613 using this procedure unless you know what you are doing.
7616 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7617 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7618 @var{target} [@var{system}]
7619 Monadic version of @code{package-derivation} and
7620 @code{package-cross-derivation} (@pxref{Defining Packages}).
7625 @section G-Expressions
7627 @cindex G-expression
7628 @cindex build code quoting
7629 So we have ``derivations'', which represent a sequence of build actions
7630 to be performed to produce an item in the store (@pxref{Derivations}).
7631 These build actions are performed when asking the daemon to actually
7632 build the derivations; they are run by the daemon in a container
7633 (@pxref{Invoking guix-daemon}).
7635 @cindex strata of code
7636 It should come as no surprise that we like to write these build actions
7637 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7638 code@footnote{The term @dfn{stratum} in this context was coined by
7639 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7640 Kiselyov, who has written insightful
7641 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7642 on this topic}, refers to this kind of code generation as
7643 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7644 to the daemon, etc.---and the ``build code''---code that actually
7645 performs build actions, such as making directories, invoking
7646 @command{make}, etc.
7648 To describe a derivation and its build actions, one typically needs to
7649 embed build code inside host code. It boils down to manipulating build
7650 code as data, and the homoiconicity of Scheme---code has a direct
7651 representation as data---comes in handy for that. But we need more than
7652 the normal @code{quasiquote} mechanism in Scheme to construct build
7655 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7656 S-expressions adapted to build expressions. G-expressions, or
7657 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7658 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7659 @code{#$}, and @code{#$@@}), which are comparable to
7660 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7661 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7662 GNU Guile Reference Manual}). However, there are major differences:
7666 Gexps are meant to be written to a file and run or manipulated by other
7670 When a high-level object such as a package or derivation is unquoted
7671 inside a gexp, the result is as if its output file name had been
7675 Gexps carry information about the packages or derivations they refer to,
7676 and these dependencies are automatically added as inputs to the build
7677 processes that use them.
7680 @cindex lowering, of high-level objects in gexps
7681 This mechanism is not limited to package and derivation
7682 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7683 derivations or files in the store can be defined,
7684 such that these objects can also be inserted
7685 into gexps. For example, a useful type of high-level objects that can be
7686 inserted in a gexp is ``file-like objects'', which make it easy to
7687 add files to the store and to refer to them in
7688 derivations and such (see @code{local-file} and @code{plain-file}
7691 To illustrate the idea, here is an example of a gexp:
7698 (symlink (string-append #$coreutils "/bin/ls")
7702 This gexp can be passed to @code{gexp->derivation}; we obtain a
7703 derivation that builds a directory containing exactly one symlink to
7704 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7707 (gexp->derivation "the-thing" build-exp)
7710 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7711 substituted to the reference to the @var{coreutils} package in the
7712 actual build code, and @var{coreutils} is automatically made an input to
7713 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7714 output)}) is replaced by a string containing the directory name of the
7715 output of the derivation.
7717 @cindex cross compilation
7718 In a cross-compilation context, it is useful to distinguish between
7719 references to the @emph{native} build of a package---that can run on the
7720 host---versus references to cross builds of a package. To that end, the
7721 @code{#+} plays the same role as @code{#$}, but is a reference to a
7722 native package build:
7725 (gexp->derivation "vi"
7728 (mkdir (string-append #$output "/bin"))
7729 (system* (string-append #+coreutils "/bin/ln")
7731 (string-append #$emacs "/bin/emacs")
7732 (string-append #$output "/bin/vi")))
7733 #:target "aarch64-linux-gnu")
7737 In the example above, the native build of @var{coreutils} is used, so
7738 that @command{ln} can actually run on the host; but then the
7739 cross-compiled build of @var{emacs} is referenced.
7741 @cindex imported modules, for gexps
7742 @findex with-imported-modules
7743 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7744 able to use certain Guile modules from the ``host environment'' in the
7745 gexp, so those modules should be imported in the ``build environment''.
7746 The @code{with-imported-modules} form allows you to express that:
7749 (let ((build (with-imported-modules '((guix build utils))
7751 (use-modules (guix build utils))
7752 (mkdir-p (string-append #$output "/bin"))))))
7753 (gexp->derivation "empty-dir"
7756 (display "success!\n")
7761 In this example, the @code{(guix build utils)} module is automatically
7762 pulled into the isolated build environment of our gexp, such that
7763 @code{(use-modules (guix build utils))} works as expected.
7765 @cindex module closure
7766 @findex source-module-closure
7767 Usually you want the @emph{closure} of the module to be imported---i.e.,
7768 the module itself and all the modules it depends on---rather than just
7769 the module; failing to do that, attempts to use the module will fail
7770 because of missing dependent modules. The @code{source-module-closure}
7771 procedure computes the closure of a module by looking at its source file
7772 headers, which comes in handy in this case:
7775 (use-modules (guix modules)) ;for 'source-module-closure'
7777 (with-imported-modules (source-module-closure
7778 '((guix build utils)
7780 (gexp->derivation "something-with-vms"
7782 (use-modules (guix build utils)
7787 @cindex extensions, for gexps
7788 @findex with-extensions
7789 In the same vein, sometimes you want to import not just pure-Scheme
7790 modules, but also ``extensions'' such as Guile bindings to C libraries
7791 or other ``full-blown'' packages. Say you need the @code{guile-json}
7792 package available on the build side, here's how you would do it:
7795 (use-modules (gnu packages guile)) ;for 'guile-json'
7797 (with-extensions (list guile-json)
7798 (gexp->derivation "something-with-json"
7800 (use-modules (json))
7804 The syntactic form to construct gexps is summarized below.
7806 @deffn {Scheme Syntax} #~@var{exp}
7807 @deffnx {Scheme Syntax} (gexp @var{exp})
7808 Return a G-expression containing @var{exp}. @var{exp} may contain one
7809 or more of the following forms:
7813 @itemx (ungexp @var{obj})
7814 Introduce a reference to @var{obj}. @var{obj} may have one of the
7815 supported types, for example a package or a
7816 derivation, in which case the @code{ungexp} form is replaced by its
7817 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7819 If @var{obj} is a list, it is traversed and references to supported
7820 objects are substituted similarly.
7822 If @var{obj} is another gexp, its contents are inserted and its
7823 dependencies are added to those of the containing gexp.
7825 If @var{obj} is another kind of object, it is inserted as is.
7827 @item #$@var{obj}:@var{output}
7828 @itemx (ungexp @var{obj} @var{output})
7829 This is like the form above, but referring explicitly to the
7830 @var{output} of @var{obj}---this is useful when @var{obj} produces
7831 multiple outputs (@pxref{Packages with Multiple Outputs}).
7834 @itemx #+@var{obj}:output
7835 @itemx (ungexp-native @var{obj})
7836 @itemx (ungexp-native @var{obj} @var{output})
7837 Same as @code{ungexp}, but produces a reference to the @emph{native}
7838 build of @var{obj} when used in a cross compilation context.
7840 @item #$output[:@var{output}]
7841 @itemx (ungexp output [@var{output}])
7842 Insert a reference to derivation output @var{output}, or to the main
7843 output when @var{output} is omitted.
7845 This only makes sense for gexps passed to @code{gexp->derivation}.
7848 @itemx (ungexp-splicing @var{lst})
7849 Like the above, but splices the contents of @var{lst} inside the
7853 @itemx (ungexp-native-splicing @var{lst})
7854 Like the above, but refers to native builds of the objects listed in
7859 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7860 of the @code{gexp?} type (see below).
7863 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7864 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7865 in their execution environment.
7867 Each item in @var{modules} can be the name of a module, such as
7868 @code{(guix build utils)}, or it can be a module name, followed by an
7869 arrow, followed by a file-like object:
7872 `((guix build utils)
7874 ((guix config) => ,(scheme-file "config.scm"
7875 #~(define-module @dots{}))))
7879 In the example above, the first two modules are taken from the search
7880 path, and the last one is created from the given file-like object.
7882 This form has @emph{lexical} scope: it has an effect on the gexps
7883 directly defined in @var{body}@dots{}, but not on those defined, say, in
7884 procedures called from @var{body}@dots{}.
7887 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7888 Mark the gexps defined in @var{body}@dots{} as requiring
7889 @var{extensions} in their build and execution environment.
7890 @var{extensions} is typically a list of package objects such as those
7891 defined in the @code{(gnu packages guile)} module.
7893 Concretely, the packages listed in @var{extensions} are added to the
7894 load path while compiling imported modules in @var{body}@dots{}; they
7895 are also added to the load path of the gexp returned by
7899 @deffn {Scheme Procedure} gexp? @var{obj}
7900 Return @code{#t} if @var{obj} is a G-expression.
7903 G-expressions are meant to be written to disk, either as code building
7904 some derivation, or as plain files in the store. The monadic procedures
7905 below allow you to do that (@pxref{The Store Monad}, for more
7906 information about monads).
7908 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7909 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7910 [#:hash #f] [#:hash-algo #f] @
7911 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7912 [#:module-path @code{%load-path}] @
7913 [#:effective-version "2.2"] @
7914 [#:references-graphs #f] [#:allowed-references #f] @
7915 [#:disallowed-references #f] @
7916 [#:leaked-env-vars #f] @
7917 [#:script-name (string-append @var{name} "-builder")] @
7918 [#:deprecation-warnings #f] @
7919 [#:local-build? #f] [#:substitutable? #t] @
7920 [#:properties '()] [#:guile-for-build #f]
7921 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7922 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7923 stored in a file called @var{script-name}. When @var{target} is true,
7924 it is used as the cross-compilation target triplet for packages referred
7927 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7929 make @var{modules} available in the evaluation context of @var{exp};
7930 @var{modules} is a list of names of Guile modules searched in
7931 @var{module-path} to be copied in the store, compiled, and made available in
7932 the load path during the execution of @var{exp}---e.g., @code{((guix
7933 build utils) (guix build gnu-build-system))}.
7935 @var{effective-version} determines the string to use when adding extensions of
7936 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7938 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7941 When @var{references-graphs} is true, it must be a list of tuples of one of the
7945 (@var{file-name} @var{package})
7946 (@var{file-name} @var{package} @var{output})
7947 (@var{file-name} @var{derivation})
7948 (@var{file-name} @var{derivation} @var{output})
7949 (@var{file-name} @var{store-item})
7952 The right-hand-side of each element of @var{references-graphs} is automatically made
7953 an input of the build process of @var{exp}. In the build environment, each
7954 @var{file-name} contains the reference graph of the corresponding item, in a simple
7957 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7958 In the latter case, the list denotes store items that the result is allowed to
7959 refer to. Any reference to another store item will lead to a build error.
7960 Similarly for @var{disallowed-references}, which can list items that must not be
7961 referenced by the outputs.
7963 @var{deprecation-warnings} determines whether to show deprecation warnings while
7964 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7966 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7969 @cindex file-like objects
7970 The @code{local-file}, @code{plain-file}, @code{computed-file},
7971 @code{program-file}, and @code{scheme-file} procedures below return
7972 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7973 these objects lead to a file in the store. Consider this G-expression:
7976 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7977 #$(local-file "/tmp/my-nscd.conf"))
7980 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7981 to the store. Once expanded, for instance @i{via}
7982 @code{gexp->derivation}, the G-expression refers to that copy under
7983 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7984 does not have any effect on what the G-expression does.
7985 @code{plain-file} can be used similarly; it differs in that the file
7986 content is directly passed as a string.
7988 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7989 [#:recursive? #f] [#:select? (const #t)]
7990 Return an object representing local file @var{file} to add to the store;
7991 this object can be used in a gexp. If @var{file} is a literal string
7992 denoting a relative file name, it is looked up relative to the source
7993 file where it appears; if @var{file} is not a literal string, it is
7994 looked up relative to the current working directory at run time.
7995 @var{file} will be added to the store under @var{name}--by default the
7996 base name of @var{file}.
7998 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7999 designates a flat file and @var{recursive?} is true, its contents are added, and its
8000 permission bits are kept.
8002 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
8003 @var{stat})} for each directory entry, where @var{file} is the entry's
8004 absolute file name and @var{stat} is the result of @code{lstat}; exclude
8005 entries for which @var{select?} does not return true.
8007 This is the declarative counterpart of the @code{interned-file} monadic
8008 procedure (@pxref{The Store Monad, @code{interned-file}}).
8011 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
8012 Return an object representing a text file called @var{name} with the given
8013 @var{content} (a string or a bytevector) to be added to the store.
8015 This is the declarative counterpart of @code{text-file}.
8018 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
8019 [#:options '(#:local-build? #t)]
8020 Return an object representing the store item @var{name}, a file or
8021 directory computed by @var{gexp}. @var{options}
8022 is a list of additional arguments to pass to @code{gexp->derivation}.
8024 This is the declarative counterpart of @code{gexp->derivation}.
8027 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
8028 [#:guile (default-guile)] [#:module-path %load-path] @
8029 [#:system (%current-system)] [#:target #f]
8030 Return an executable script @var{name} that runs @var{exp} using
8031 @var{guile}, with @var{exp}'s imported modules in its search path.
8032 Look up @var{exp}'s modules in @var{module-path}.
8034 The example below builds a script that simply invokes the @command{ls}
8038 (use-modules (guix gexp) (gnu packages base))
8040 (gexp->script "list-files"
8041 #~(execl #$(file-append coreutils "/bin/ls")
8045 When ``running'' it through the store (@pxref{The Store Monad,
8046 @code{run-with-store}}), we obtain a derivation that produces an
8047 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
8050 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
8052 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
8056 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
8057 [#:guile #f] [#:module-path %load-path]
8058 Return an object representing the executable store item @var{name} that
8059 runs @var{gexp}. @var{guile} is the Guile package used to execute that
8060 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
8062 This is the declarative counterpart of @code{gexp->script}.
8065 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
8066 [#:set-load-path? #t] [#:module-path %load-path] @
8068 [#:guile (default-guile)]
8069 Return a derivation that builds a file @var{name} containing @var{exp}.
8070 When @var{splice?} is true, @var{exp} is considered to be a list of
8071 expressions that will be spliced in the resulting file.
8073 When @var{set-load-path?} is true, emit code in the resulting file to
8074 set @code{%load-path} and @code{%load-compiled-path} to honor
8075 @var{exp}'s imported modules. Look up @var{exp}'s modules in
8078 The resulting file holds references to all the dependencies of @var{exp}
8079 or a subset thereof.
8082 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
8083 [#:splice? #f] [#:set-load-path? #t]
8084 Return an object representing the Scheme file @var{name} that contains
8087 This is the declarative counterpart of @code{gexp->file}.
8090 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
8091 Return as a monadic value a derivation that builds a text file
8092 containing all of @var{text}. @var{text} may list, in addition to
8093 strings, objects of any type that can be used in a gexp: packages,
8094 derivations, local file objects, etc. The resulting store file holds
8095 references to all these.
8097 This variant should be preferred over @code{text-file} anytime the file
8098 to create will reference items from the store. This is typically the
8099 case when building a configuration file that embeds store file names,
8103 (define (profile.sh)
8104 ;; Return the name of a shell script in the store that
8105 ;; initializes the 'PATH' environment variable.
8106 (text-file* "profile.sh"
8107 "export PATH=" coreutils "/bin:"
8108 grep "/bin:" sed "/bin\n"))
8111 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
8112 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
8113 preventing them from being garbage-collected during its lifetime.
8116 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
8117 Return an object representing store file @var{name} containing
8118 @var{text}. @var{text} is a sequence of strings and file-like objects,
8122 (mixed-text-file "profile"
8123 "export PATH=" coreutils "/bin:" grep "/bin")
8126 This is the declarative counterpart of @code{text-file*}.
8129 @deffn {Scheme Procedure} file-union @var{name} @var{files}
8130 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
8131 Each item in @var{files} must be a two-element list where the first element is the
8132 file name to use in the new directory, and the second element is a gexp
8133 denoting the target file. Here's an example:
8137 `(("hosts" ,(plain-file "hosts"
8138 "127.0.0.1 localhost"))
8139 ("bashrc" ,(plain-file "bashrc"
8140 "alias ls='ls --color=auto'"))))
8143 This yields an @code{etc} directory containing these two files.
8146 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
8147 Return a directory that is the union of @var{things}, where @var{things} is a list of
8148 file-like objects denoting directories. For example:
8151 (directory-union "guile+emacs" (list guile emacs))
8154 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
8157 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
8158 Return a file-like object that expands to the concatenation of @var{obj}
8159 and @var{suffix}, where @var{obj} is a lowerable object and each
8160 @var{suffix} is a string.
8162 As an example, consider this gexp:
8165 (gexp->script "run-uname"
8166 #~(system* #$(file-append coreutils
8170 The same effect could be achieved with:
8173 (gexp->script "run-uname"
8174 #~(system* (string-append #$coreutils
8178 There is one difference though: in the @code{file-append} case, the
8179 resulting script contains the absolute file name as a string, whereas in
8180 the second case, the resulting script contains a @code{(string-append
8181 @dots{})} expression to construct the file name @emph{at run time}.
8184 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
8185 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
8186 Bind @var{system} to the currently targeted system---e.g.,
8187 @code{"x86_64-linux"}---within @var{body}.
8189 In the second case, additionally bind @var{target} to the current
8190 cross-compilation target---a GNU triplet such as
8191 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
8194 @code{let-system} is useful in the occasional case where the object
8195 spliced into the gexp depends on the target system, as in this example:
8199 #+(let-system system
8200 (cond ((string-prefix? "armhf-" system)
8201 (file-append qemu "/bin/qemu-system-arm"))
8202 ((string-prefix? "x86_64-" system)
8203 (file-append qemu "/bin/qemu-system-x86_64"))
8206 "-net" "user" #$image)
8210 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
8211 This macro is similar to the @code{parameterize} form for
8212 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
8213 Guile Reference Manual}). The key difference is that it takes effect
8214 when the file-like object returned by @var{exp} is lowered to a
8215 derivation or store item.
8217 A typical use of @code{with-parameters} is to force the system in effect
8221 (with-parameters ((%current-system "i686-linux"))
8225 The example above returns an object that corresponds to the i686 build
8226 of Coreutils, regardless of the current value of @code{%current-system}.
8230 Of course, in addition to gexps embedded in ``host'' code, there are
8231 also modules containing build tools. To make it clear that they are
8232 meant to be used in the build stratum, these modules are kept in the
8233 @code{(guix build @dots{})} name space.
8235 @cindex lowering, of high-level objects in gexps
8236 Internally, high-level objects are @dfn{lowered}, using their compiler,
8237 to either derivations or store items. For instance, lowering a package
8238 yields a derivation, and lowering a @code{plain-file} yields a store
8239 item. This is achieved using the @code{lower-object} monadic procedure.
8241 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
8243 Return as a value in @code{%store-monad} the derivation or store item
8244 corresponding to @var{obj} for @var{system}, cross-compiling for
8245 @var{target} if @var{target} is true. @var{obj} must be an object that
8246 has an associated gexp compiler, such as a @code{<package>}.
8249 @node Invoking guix repl
8250 @section Invoking @command{guix repl}
8252 @cindex REPL, read-eval-print loop, script
8253 The @command{guix repl} command makes it easier to program Guix in Guile
8254 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
8255 programming (@pxref{Using Guile Interactively,,, guile,
8256 GNU Guile Reference Manual}), or by running Guile scripts
8257 (@pxref{Running Guile Scripts,,, guile,
8258 GNU Guile Reference Manual}).
8259 Compared to just launching the @command{guile}
8260 command, @command{guix repl} guarantees that all the Guix modules and all its
8261 dependencies are available in the search path.
8263 The general syntax is:
8266 guix repl @var{options} [@var{file} @var{args}]
8269 When a @var{file} argument is provided, @var{file} is
8270 executed as a Guile scripts:
8273 guix repl my-script.scm
8276 To pass arguments to the script, use @code{--} to prevent them from
8277 being interpreted as arguments to @command{guix repl} itself:
8280 guix repl -- my-script.scm --input=foo.txt
8283 To make a script executable directly from the shell, using the guix
8284 executable that is on the user's search path, add the following two
8285 lines at the top of the script:
8288 @code{#!/usr/bin/env -S guix repl --}
8292 Without a file name argument, a Guile REPL is started:
8296 scheme@@(guile-user)> ,use (gnu packages base)
8297 scheme@@(guile-user)> coreutils
8298 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
8302 In addition, @command{guix repl} implements a simple machine-readable REPL
8303 protocol for use by @code{(guix inferior)}, a facility to interact with
8304 @dfn{inferiors}, separate processes running a potentially different revision
8307 The available options are as follows:
8310 @item --type=@var{type}
8311 @itemx -t @var{type}
8312 Start a REPL of the given @var{TYPE}, which can be one of the following:
8316 This is default, and it spawns a standard full-featured Guile REPL.
8318 Spawn a REPL that uses the machine-readable protocol. This is the protocol
8319 that the @code{(guix inferior)} module speaks.
8322 @item --listen=@var{endpoint}
8323 By default, @command{guix repl} reads from standard input and writes to
8324 standard output. When this option is passed, it will instead listen for
8325 connections on @var{endpoint}. Here are examples of valid options:
8328 @item --listen=tcp:37146
8329 Accept connections on localhost on port 37146.
8331 @item --listen=unix:/tmp/socket
8332 Accept connections on the Unix-domain socket @file{/tmp/socket}.
8335 @item --load-path=@var{directory}
8336 @itemx -L @var{directory}
8337 Add @var{directory} to the front of the package module search path
8338 (@pxref{Package Modules}).
8340 This allows users to define their own packages and make them visible to
8344 Inhibit loading of the @file{~/.guile} file. By default, that
8345 configuration file is loaded when spawning a @code{guile} REPL.
8348 @c *********************************************************************
8352 This section describes Guix command-line utilities. Some of them are
8353 primarily targeted at developers and users who write new package
8354 definitions, while others are more generally useful. They complement
8355 the Scheme programming interface of Guix in a convenient way.
8358 * Invoking guix build:: Building packages from the command line.
8359 * Invoking guix edit:: Editing package definitions.
8360 * Invoking guix download:: Downloading a file and printing its hash.
8361 * Invoking guix hash:: Computing the cryptographic hash of a file.
8362 * Invoking guix import:: Importing package definitions.
8363 * Invoking guix refresh:: Updating package definitions.
8364 * Invoking guix lint:: Finding errors in package definitions.
8365 * Invoking guix size:: Profiling disk usage.
8366 * Invoking guix graph:: Visualizing the graph of packages.
8367 * Invoking guix publish:: Sharing substitutes.
8368 * Invoking guix challenge:: Challenging substitute servers.
8369 * Invoking guix copy:: Copying to and from a remote store.
8370 * Invoking guix container:: Process isolation.
8371 * Invoking guix weather:: Assessing substitute availability.
8372 * Invoking guix processes:: Listing client processes.
8375 @node Invoking guix build
8376 @section Invoking @command{guix build}
8378 @cindex package building
8379 @cindex @command{guix build}
8380 The @command{guix build} command builds packages or derivations and
8381 their dependencies, and prints the resulting store paths. Note that it
8382 does not modify the user's profile---this is the job of the
8383 @command{guix package} command (@pxref{Invoking guix package}). Thus,
8384 it is mainly useful for distribution developers.
8386 The general syntax is:
8389 guix build @var{options} @var{package-or-derivation}@dots{}
8392 As an example, the following command builds the latest versions of Emacs
8393 and of Guile, displays their build logs, and finally displays the
8394 resulting directories:
8397 guix build emacs guile
8400 Similarly, the following command builds all the available packages:
8403 guix build --quiet --keep-going \
8404 `guix package -A | cut -f1,2 --output-delimiter=@@`
8407 @var{package-or-derivation} may be either the name of a package found in
8408 the software distribution such as @code{coreutils} or
8409 @code{coreutils@@8.20}, or a derivation such as
8410 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
8411 package with the corresponding name (and optionally version) is searched
8412 for among the GNU distribution modules (@pxref{Package Modules}).
8414 Alternatively, the @option{--expression} option may be used to specify a
8415 Scheme expression that evaluates to a package; this is useful when
8416 disambiguating among several same-named packages or package variants is
8419 There may be zero or more @var{options}. The available options are
8420 described in the subsections below.
8423 * Common Build Options:: Build options for most commands.
8424 * Package Transformation Options:: Creating variants of packages.
8425 * Additional Build Options:: Options specific to 'guix build'.
8426 * Debugging Build Failures:: Real life packaging experience.
8429 @node Common Build Options
8430 @subsection Common Build Options
8432 A number of options that control the build process are common to
8433 @command{guix build} and other commands that can spawn builds, such as
8434 @command{guix package} or @command{guix archive}. These are the
8439 @item --load-path=@var{directory}
8440 @itemx -L @var{directory}
8441 Add @var{directory} to the front of the package module search path
8442 (@pxref{Package Modules}).
8444 This allows users to define their own packages and make them visible to
8445 the command-line tools.
8449 Keep the build tree of failed builds. Thus, if a build fails, its build
8450 tree is kept under @file{/tmp}, in a directory whose name is shown at
8451 the end of the build log. This is useful when debugging build issues.
8452 @xref{Debugging Build Failures}, for tips and tricks on how to debug
8455 This option implies @option{--no-offload}, and it has no effect when
8456 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
8457 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
8461 Keep going when some of the derivations fail to build; return only once
8462 all the builds have either completed or failed.
8464 The default behavior is to stop as soon as one of the specified
8465 derivations has failed.
8469 Do not build the derivations.
8471 @anchor{fallback-option}
8473 When substituting a pre-built binary fails, fall back to building
8474 packages locally (@pxref{Substitution Failure}).
8476 @item --substitute-urls=@var{urls}
8477 @anchor{client-substitute-urls}
8478 Consider @var{urls} the whitespace-separated list of substitute source
8479 URLs, overriding the default list of URLs of @command{guix-daemon}
8480 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
8482 This means that substitutes may be downloaded from @var{urls}, provided
8483 they are signed by a key authorized by the system administrator
8484 (@pxref{Substitutes}).
8486 When @var{urls} is the empty string, substitutes are effectively
8489 @item --no-substitutes
8490 Do not use substitutes for build products. That is, always build things
8491 locally instead of allowing downloads of pre-built binaries
8492 (@pxref{Substitutes}).
8495 Do not ``graft'' packages. In practice, this means that package updates
8496 available as grafts are not applied. @xref{Security Updates}, for more
8497 information on grafts.
8499 @item --rounds=@var{n}
8500 Build each derivation @var{n} times in a row, and raise an error if
8501 consecutive build results are not bit-for-bit identical.
8503 This is a useful way to detect non-deterministic builds processes.
8504 Non-deterministic build processes are a problem because they make it
8505 practically impossible for users to @emph{verify} whether third-party
8506 binaries are genuine. @xref{Invoking guix challenge}, for more.
8508 Note that, currently, the differing build results are not kept around,
8509 so you will have to manually investigate in case of an error---e.g., by
8510 stashing one of the build results with @code{guix archive --export}
8511 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8515 Do not use offload builds to other machines (@pxref{Daemon Offload
8516 Setup}). That is, always build things locally instead of offloading
8517 builds to remote machines.
8519 @item --max-silent-time=@var{seconds}
8520 When the build or substitution process remains silent for more than
8521 @var{seconds}, terminate it and report a build failure.
8523 By default, the daemon's setting is honored (@pxref{Invoking
8524 guix-daemon, @option{--max-silent-time}}).
8526 @item --timeout=@var{seconds}
8527 Likewise, when the build or substitution process lasts for more than
8528 @var{seconds}, terminate it and report a build failure.
8530 By default, the daemon's setting is honored (@pxref{Invoking
8531 guix-daemon, @option{--timeout}}).
8533 @c Note: This option is actually not part of %standard-build-options but
8534 @c most programs honor it.
8535 @cindex verbosity, of the command-line tools
8536 @cindex build logs, verbosity
8537 @item -v @var{level}
8538 @itemx --verbosity=@var{level}
8539 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8540 output is produced, 1 is for quiet output, and 2 shows all the build log
8541 output on standard error.
8543 @item --cores=@var{n}
8545 Allow the use of up to @var{n} CPU cores for the build. The special
8546 value @code{0} means to use as many CPU cores as available.
8548 @item --max-jobs=@var{n}
8550 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8551 guix-daemon, @option{--max-jobs}}, for details about this option and the
8552 equivalent @command{guix-daemon} option.
8554 @item --debug=@var{level}
8555 Produce debugging output coming from the build daemon. @var{level} must be an
8556 integer between 0 and 5; higher means more verbose output. Setting a level of
8557 4 or more may be helpful when debugging setup issues with the build daemon.
8561 Behind the scenes, @command{guix build} is essentially an interface to
8562 the @code{package-derivation} procedure of the @code{(guix packages)}
8563 module, and to the @code{build-derivations} procedure of the @code{(guix
8564 derivations)} module.
8566 In addition to options explicitly passed on the command line,
8567 @command{guix build} and other @command{guix} commands that support
8568 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
8570 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8571 Users can define this variable to a list of command line options that
8572 will automatically be used by @command{guix build} and other
8573 @command{guix} commands that can perform builds, as in the example
8577 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8580 These options are parsed independently, and the result is appended to
8581 the parsed command-line options.
8585 @node Package Transformation Options
8586 @subsection Package Transformation Options
8588 @cindex package variants
8589 Another set of command-line options supported by @command{guix build}
8590 and also @command{guix package} are @dfn{package transformation
8591 options}. These are options that make it possible to define @dfn{package
8592 variants}---for instance, packages built from different source code.
8593 This is a convenient way to create customized packages on the fly
8594 without having to type in the definitions of package variants
8595 (@pxref{Defining Packages}).
8599 @item --with-source=@var{source}
8600 @itemx --with-source=@var{package}=@var{source}
8601 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8602 Use @var{source} as the source of @var{package}, and @var{version} as
8604 @var{source} must be a file name or a URL, as for @command{guix
8605 download} (@pxref{Invoking guix download}).
8607 When @var{package} is omitted,
8608 it is taken to be the package name specified on the
8609 command line that matches the base of @var{source}---e.g.,
8610 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8611 package is @code{guile}.
8613 Likewise, when @var{version} is omitted, the version string is inferred from
8614 @var{source}; in the previous example, it is @code{2.0.10}.
8616 This option allows users to try out versions of packages other than the
8617 one provided by the distribution. The example below downloads
8618 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8619 the @code{ed} package:
8622 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8625 As a developer, @option{--with-source} makes it easy to test release
8629 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8632 @dots{} or to build from a checkout in a pristine environment:
8635 $ git clone git://git.sv.gnu.org/guix.git
8636 $ guix build guix --with-source=guix@@1.0=./guix
8639 @item --with-input=@var{package}=@var{replacement}
8640 Replace dependency on @var{package} by a dependency on
8641 @var{replacement}. @var{package} must be a package name, and
8642 @var{replacement} must be a package specification such as @code{guile}
8643 or @code{guile@@1.8}.
8645 For instance, the following command builds Guix, but replaces its
8646 dependency on the current stable version of Guile with a dependency on
8647 the legacy version of Guile, @code{guile@@2.0}:
8650 guix build --with-input=guile=guile@@2.0 guix
8653 This is a recursive, deep replacement. So in this example, both
8654 @code{guix} and its dependency @code{guile-json} (which also depends on
8655 @code{guile}) get rebuilt against @code{guile@@2.0}.
8657 This is implemented using the @code{package-input-rewriting} Scheme
8658 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8660 @item --with-graft=@var{package}=@var{replacement}
8661 This is similar to @option{--with-input} but with an important difference:
8662 instead of rebuilding the whole dependency chain, @var{replacement} is
8663 built and then @dfn{grafted} onto the binaries that were initially
8664 referring to @var{package}. @xref{Security Updates}, for more
8665 information on grafts.
8667 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8668 and all its dependencies, replacing references to the version of GnuTLS
8669 they currently refer to:
8672 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8675 This has the advantage of being much faster than rebuilding everything.
8676 But there is a caveat: it works if and only if @var{package} and
8677 @var{replacement} are strictly compatible---for example, if they provide
8678 a library, the application binary interface (ABI) of those libraries
8679 must be compatible. If @var{replacement} is somehow incompatible with
8680 @var{package}, then the resulting package may be unusable. Use with
8683 @item --with-git-url=@var{package}=@var{url}
8684 @cindex Git, using the latest commit
8685 @cindex latest commit, building
8686 Build @var{package} from the latest commit of the @code{master} branch of the
8687 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8690 For example, the following command builds the NumPy Python library against the
8691 latest commit of the master branch of Python itself:
8694 guix build python-numpy \
8695 --with-git-url=python=https://github.com/python/cpython
8698 This option can also be combined with @option{--with-branch} or
8699 @option{--with-commit} (see below).
8701 @cindex continuous integration
8702 Obviously, since it uses the latest commit of the given branch, the result of
8703 such a command varies over time. Nevertheless it is a convenient way to
8704 rebuild entire software stacks against the latest commit of one or more
8705 packages. This is particularly useful in the context of continuous
8708 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8709 consecutive accesses to the same repository. You may want to clean it up once
8710 in a while to save disk space.
8712 @item --with-branch=@var{package}=@var{branch}
8713 Build @var{package} from the latest commit of @var{branch}. If the
8714 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8715 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8716 repository URL is taken from that @code{source}. Otherwise you have to use
8717 @option{--with-git-url} to specify the URL of the Git repository.
8719 For instance, the following command builds @code{guile-sqlite3} from the
8720 latest commit of its @code{master} branch, and then builds @code{guix} (which
8721 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8722 specific @code{guile-sqlite3} build:
8725 guix build --with-branch=guile-sqlite3=master cuirass
8728 @item --with-commit=@var{package}=@var{commit}
8729 This is similar to @option{--with-branch}, except that it builds from
8730 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8731 Git commit SHA1 identifier or a tag.
8734 @node Additional Build Options
8735 @subsection Additional Build Options
8737 The command-line options presented below are specific to @command{guix
8744 Build quietly, without displaying the build log; this is equivalent to
8745 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8746 (or similar) and can always be retrieved using the @option{--log-file} option.
8748 @item --file=@var{file}
8749 @itemx -f @var{file}
8750 Build the package, derivation, or other file-like object that the code within
8751 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8753 As an example, @var{file} might contain a package definition like this
8754 (@pxref{Defining Packages}):
8757 @include package-hello.scm
8760 The @var{file} may also contain a JSON representation of one or more
8761 package definitions. Running @code{guix build -f} on @file{hello.json}
8762 with the following contents would result in building the packages
8763 @code{myhello} and @code{greeter}:
8766 @verbatiminclude package-hello.json
8769 @item --manifest=@var{manifest}
8770 @itemx -m @var{manifest}
8771 Build all packages listed in the given @var{manifest}
8772 (@pxref{profile-manifest, @option{--manifest}}).
8774 @item --expression=@var{expr}
8775 @itemx -e @var{expr}
8776 Build the package or derivation @var{expr} evaluates to.
8778 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8779 guile-1.8)}, which unambiguously designates this specific variant of
8780 version 1.8 of Guile.
8782 Alternatively, @var{expr} may be a G-expression, in which case it is used
8783 as a build program passed to @code{gexp->derivation}
8784 (@pxref{G-Expressions}).
8786 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8787 (@pxref{The Store Monad}). The procedure must return a derivation as a
8788 monadic value, which is then passed through @code{run-with-store}.
8792 Build the source derivations of the packages, rather than the packages
8795 For instance, @code{guix build -S gcc} returns something like
8796 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8799 The returned source tarball is the result of applying any patches and
8800 code snippets specified in the package @code{origin} (@pxref{Defining
8803 Note that @command{guix build -S} compiles the sources only of the
8804 specified packages. They do not include the sources of statically
8805 linked dependencies and by themselves are insufficient for reproducing
8809 Fetch and return the source of @var{package-or-derivation} and all their
8810 dependencies, recursively. This is a handy way to obtain a local copy
8811 of all the source code needed to build @var{packages}, allowing you to
8812 eventually build them even without network access. It is an extension
8813 of the @option{--source} option and can accept one of the following
8814 optional argument values:
8818 This value causes the @option{--sources} option to behave in the same way
8819 as the @option{--source} option.
8822 Build the source derivations of all packages, including any source that
8823 might be listed as @code{inputs}. This is the default value.
8826 $ guix build --sources tzdata
8827 The following derivations will be built:
8828 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8829 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8833 Build the source derivations of all packages, as well of all transitive
8834 inputs to the packages. This can be used e.g.@: to
8835 prefetch package source for later offline building.
8838 $ guix build --sources=transitive tzdata
8839 The following derivations will be built:
8840 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8841 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8842 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8843 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8844 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8845 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8851 @item --system=@var{system}
8852 @itemx -s @var{system}
8853 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8854 the system type of the build host. The @command{guix build} command allows
8855 you to repeat this option several times, in which case it builds for all the
8856 specified systems; other commands ignore extraneous @option{-s} options.
8859 The @option{--system} flag is for @emph{native} compilation and must not
8860 be confused with cross-compilation. See @option{--target} below for
8861 information on cross-compilation.
8864 An example use of this is on Linux-based systems, which can emulate
8865 different personalities. For instance, passing
8866 @option{--system=i686-linux} on an @code{x86_64-linux} system or
8867 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
8868 you to build packages in a complete 32-bit environment.
8871 Building for an @code{armhf-linux} system is unconditionally enabled on
8872 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8873 allow for this functionality, notably the ThunderX.
8876 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8877 is enabled (@pxref{Virtualization Services,
8878 @code{qemu-binfmt-service-type}}), you can build for any system for
8879 which a QEMU @code{binfmt_misc} handler is installed.
8881 Builds for a system other than that of the machine you are using can
8882 also be offloaded to a remote machine of the right architecture.
8883 @xref{Daemon Offload Setup}, for more information on offloading.
8885 @item --target=@var{triplet}
8886 @cindex cross-compilation
8887 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8888 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8889 configuration triplets,, autoconf, Autoconf}).
8891 @anchor{build-check}
8893 @cindex determinism, checking
8894 @cindex reproducibility, checking
8895 Rebuild @var{package-or-derivation}, which are already available in the
8896 store, and raise an error if the build results are not bit-for-bit
8899 This mechanism allows you to check whether previously installed
8900 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8901 of a package is deterministic. @xref{Invoking guix challenge}, for more
8902 background information and tools.
8904 When used in conjunction with @option{--keep-failed}, the differing
8905 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8906 This makes it easy to look for differences between the two results.
8909 @cindex repairing store items
8910 @cindex corruption, recovering from
8911 Attempt to repair the specified store items, if they are corrupt, by
8912 re-downloading or rebuilding them.
8914 This operation is not atomic and thus restricted to @code{root}.
8918 Return the derivation paths, not the output paths, of the given
8921 @item --root=@var{file}
8922 @itemx -r @var{file}
8923 @cindex GC roots, adding
8924 @cindex garbage collector roots, adding
8925 Make @var{file} a symlink to the result, and register it as a garbage
8928 Consequently, the results of this @command{guix build} invocation are
8929 protected from garbage collection until @var{file} is removed. When
8930 that option is omitted, build results are eligible for garbage
8931 collection as soon as the build completes. @xref{Invoking guix gc}, for
8935 @cindex build logs, access
8936 Return the build log file names or URLs for the given
8937 @var{package-or-derivation}, or raise an error if build logs are
8940 This works regardless of how packages or derivations are specified. For
8941 instance, the following invocations are equivalent:
8944 guix build --log-file `guix build -d guile`
8945 guix build --log-file `guix build guile`
8946 guix build --log-file guile
8947 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8950 If a log is unavailable locally, and unless @option{--no-substitutes} is
8951 passed, the command looks for a corresponding log on one of the
8952 substitute servers (as specified with @option{--substitute-urls}).
8954 So for instance, imagine you want to see the build log of GDB on MIPS,
8955 but you are actually on an @code{x86_64} machine:
8958 $ guix build --log-file gdb -s aarch64-linux
8959 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8962 You can freely access a huge library of build logs!
8965 @node Debugging Build Failures
8966 @subsection Debugging Build Failures
8968 @cindex build failures, debugging
8969 When defining a new package (@pxref{Defining Packages}), you will
8970 probably find yourself spending some time debugging and tweaking the
8971 build until it succeeds. To do that, you need to operate the build
8972 commands yourself in an environment as close as possible to the one the
8975 To that end, the first thing to do is to use the @option{--keep-failed}
8976 or @option{-K} option of @command{guix build}, which will keep the
8977 failed build tree in @file{/tmp} or whatever directory you specified as
8978 @env{TMPDIR} (@pxref{Invoking guix build, @option{--keep-failed}}).
8980 From there on, you can @command{cd} to the failed build tree and source
8981 the @file{environment-variables} file, which contains all the
8982 environment variable definitions that were in place when the build
8983 failed. So let's say you're debugging a build failure in package
8984 @code{foo}; a typical session would look like this:
8988 @dots{} @i{build fails}
8989 $ cd /tmp/guix-build-foo.drv-0
8990 $ source ./environment-variables
8994 Now, you can invoke commands as if you were the daemon (almost) and
8995 troubleshoot your build process.
8997 Sometimes it happens that, for example, a package's tests pass when you
8998 run them manually but they fail when the daemon runs them. This can
8999 happen because the daemon runs builds in containers where, unlike in our
9000 environment above, network access is missing, @file{/bin/sh} does not
9001 exist, etc. (@pxref{Build Environment Setup}).
9003 In such cases, you may need to run inspect the build process from within
9004 a container similar to the one the build daemon creates:
9009 $ cd /tmp/guix-build-foo.drv-0
9010 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
9011 [env]# source ./environment-variables
9015 Here, @command{guix environment -C} creates a container and spawns a new
9016 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
9017 strace gdb} part adds the @command{strace} and @command{gdb} commands to
9018 the container, which you may find handy while debugging. The
9019 @option{--no-grafts} option makes sure we get the exact same
9020 environment, with ungrafted packages (@pxref{Security Updates}, for more
9023 To get closer to a container like that used by the build daemon, we can
9024 remove @file{/bin/sh}:
9030 (Don't worry, this is harmless: this is all happening in the throw-away
9031 container created by @command{guix environment}.)
9033 The @command{strace} command is probably not in the search path, but we
9037 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
9040 In this way, not only you will have reproduced the environment variables
9041 the daemon uses, you will also be running the build process in a container
9042 similar to the one the daemon uses.
9045 @node Invoking guix edit
9046 @section Invoking @command{guix edit}
9048 @cindex @command{guix edit}
9049 @cindex package definition, editing
9050 So many packages, so many source files! The @command{guix edit} command
9051 facilitates the life of users and packagers by pointing their editor at
9052 the source file containing the definition of the specified packages.
9056 guix edit gcc@@4.9 vim
9060 launches the program specified in the @env{VISUAL} or in the
9061 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
9064 If you are using a Guix Git checkout (@pxref{Building from Git}), or
9065 have created your own packages on @env{GUIX_PACKAGE_PATH}
9066 (@pxref{Package Modules}), you will be able to edit the package
9067 recipes. In other cases, you will be able to examine the read-only recipes
9068 for packages currently in the store.
9070 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
9071 @option{--load-path=@var{directory}} (or in short @option{-L
9072 @var{directory}}) allows you to add @var{directory} to the front of the
9073 package module search path and so make your own packages visible.
9075 @node Invoking guix download
9076 @section Invoking @command{guix download}
9078 @cindex @command{guix download}
9079 @cindex downloading package sources
9080 When writing a package definition, developers typically need to download
9081 a source tarball, compute its SHA256 hash, and write that
9082 hash in the package definition (@pxref{Defining Packages}). The
9083 @command{guix download} tool helps with this task: it downloads a file
9084 from the given URI, adds it to the store, and prints both its file name
9085 in the store and its SHA256 hash.
9087 The fact that the downloaded file is added to the store saves bandwidth:
9088 when the developer eventually tries to build the newly defined package
9089 with @command{guix build}, the source tarball will not have to be
9090 downloaded again because it is already in the store. It is also a
9091 convenient way to temporarily stash files, which may be deleted
9092 eventually (@pxref{Invoking guix gc}).
9094 The @command{guix download} command supports the same URIs as used in
9095 package definitions. In particular, it supports @code{mirror://} URIs.
9096 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
9097 Guile bindings for GnuTLS are available in the user's environment; when
9098 they are not available, an error is raised. @xref{Guile Preparations,
9099 how to install the GnuTLS bindings for Guile,, gnutls-guile,
9100 GnuTLS-Guile}, for more information.
9102 @command{guix download} verifies HTTPS server certificates by loading
9103 the certificates of X.509 authorities from the directory pointed to by
9104 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
9105 Certificates}), unless @option{--no-check-certificate} is used.
9107 The following options are available:
9110 @item --hash=@var{algorithm}
9111 @itemx -H @var{algorithm}
9112 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
9113 hash}, for more information.
9115 @item --format=@var{fmt}
9117 Write the hash in the format specified by @var{fmt}. For more
9118 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
9120 @item --no-check-certificate
9121 Do not validate the X.509 certificates of HTTPS servers.
9123 When using this option, you have @emph{absolutely no guarantee} that you
9124 are communicating with the authentic server responsible for the given
9125 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
9127 @item --output=@var{file}
9128 @itemx -o @var{file}
9129 Save the downloaded file to @var{file} instead of adding it to the
9133 @node Invoking guix hash
9134 @section Invoking @command{guix hash}
9136 @cindex @command{guix hash}
9137 The @command{guix hash} command computes the SHA256 hash of a file.
9138 It is primarily a convenience tool for anyone contributing to the
9139 distribution: it computes the cryptographic hash of a file, which can be
9140 used in the definition of a package (@pxref{Defining Packages}).
9142 The general syntax is:
9145 guix hash @var{option} @var{file}
9148 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
9149 hash of data read from standard input. @command{guix hash} has the
9154 @item --hash=@var{algorithm}
9155 @itemx -H @var{algorithm}
9156 Compute a hash using the specified @var{algorithm}, @code{sha256} by
9159 @var{algorithm} must the name of a cryptographic hash algorithm
9160 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
9161 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
9164 @item --format=@var{fmt}
9166 Write the hash in the format specified by @var{fmt}.
9168 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
9169 (@code{hex} and @code{hexadecimal} can be used as well).
9171 If the @option{--format} option is not specified, @command{guix hash}
9172 will output the hash in @code{nix-base32}. This representation is used
9173 in the definitions of packages.
9177 Compute the hash on @var{file} recursively.
9179 In this case, the hash is computed on an archive containing @var{file},
9180 including its children if it is a directory. Some of the metadata of
9181 @var{file} is part of the archive; for instance, when @var{file} is a
9182 regular file, the hash is different depending on whether @var{file} is
9183 executable or not. Metadata such as time stamps has no impact on the
9184 hash (@pxref{Invoking guix archive}).
9185 @c FIXME: Replace xref above with xref to an ``Archive'' section when
9190 When combined with @option{--recursive}, exclude version control system
9191 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
9194 As an example, here is how you would compute the hash of a Git checkout,
9195 which is useful when using the @code{git-fetch} method (@pxref{origin
9199 $ git clone http://example.org/foo.git
9205 @node Invoking guix import
9206 @section Invoking @command{guix import}
9208 @cindex importing packages
9209 @cindex package import
9210 @cindex package conversion
9211 @cindex Invoking @command{guix import}
9212 The @command{guix import} command is useful for people who would like to
9213 add a package to the distribution with as little work as
9214 possible---a legitimate demand. The command knows of a few
9215 repositories from which it can ``import'' package metadata. The result
9216 is a package definition, or a template thereof, in the format we know
9217 (@pxref{Defining Packages}).
9219 The general syntax is:
9222 guix import @var{importer} @var{options}@dots{}
9225 @var{importer} specifies the source from which to import package
9226 metadata, and @var{options} specifies a package identifier and other
9227 options specific to @var{importer}.
9229 Some of the importers rely on the ability to run the @command{gpgv} command.
9230 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
9233 Currently, the available ``importers'' are:
9237 Import metadata for the given GNU package. This provides a template
9238 for the latest version of that GNU package, including the hash of its
9239 source tarball, and its canonical synopsis and description.
9241 Additional information such as the package dependencies and its
9242 license needs to be figured out manually.
9244 For example, the following command returns a package definition for
9248 guix import gnu hello
9251 Specific command-line options are:
9254 @item --key-download=@var{policy}
9255 As for @command{guix refresh}, specify the policy to handle missing
9256 OpenPGP keys when verifying the package signature. @xref{Invoking guix
9257 refresh, @option{--key-download}}.
9262 Import metadata from the @uref{https://pypi.python.org/, Python Package
9263 Index}. Information is taken from the JSON-formatted description
9264 available at @code{pypi.python.org} and usually includes all the relevant
9265 information, including package dependencies. For maximum efficiency, it
9266 is recommended to install the @command{unzip} utility, so that the
9267 importer can unzip Python wheels and gather data from them.
9269 The command below imports metadata for the @code{itsdangerous} Python
9273 guix import pypi itsdangerous
9279 Traverse the dependency graph of the given upstream package recursively
9280 and generate package expressions for all those packages that are not yet
9286 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
9287 is taken from the JSON-formatted description available at
9288 @code{rubygems.org} and includes most relevant information, including
9289 runtime dependencies. There are some caveats, however. The metadata
9290 doesn't distinguish between synopses and descriptions, so the same string
9291 is used for both fields. Additionally, the details of non-Ruby
9292 dependencies required to build native extensions is unavailable and left
9293 as an exercise to the packager.
9295 The command below imports metadata for the @code{rails} Ruby package:
9298 guix import gem rails
9304 Traverse the dependency graph of the given upstream package recursively
9305 and generate package expressions for all those packages that are not yet
9311 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
9312 Information is taken from the JSON-formatted metadata provided through
9313 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
9314 relevant information, such as module dependencies. License information
9315 should be checked closely. If Perl is available in the store, then the
9316 @code{corelist} utility will be used to filter core modules out of the
9317 list of dependencies.
9319 The command command below imports metadata for the Acme::Boolean Perl
9323 guix import cpan Acme::Boolean
9328 @cindex Bioconductor
9329 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
9330 central repository for the @uref{https://r-project.org, GNU@tie{}R
9331 statistical and graphical environment}.
9333 Information is extracted from the @file{DESCRIPTION} file of the package.
9335 The command command below imports metadata for the Cairo R package:
9338 guix import cran Cairo
9341 When @option{--recursive} is added, the importer will traverse the
9342 dependency graph of the given upstream package recursively and generate
9343 package expressions for all those packages that are not yet in Guix.
9345 When @option{--archive=bioconductor} is added, metadata is imported from
9346 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
9347 packages for for the analysis and comprehension of high-throughput
9348 genomic data in bioinformatics.
9350 Information is extracted from the @file{DESCRIPTION} file contained in the
9353 The command below imports metadata for the GenomicRanges R package:
9356 guix import cran --archive=bioconductor GenomicRanges
9359 Finally, you can also import R packages that have not yet been published on
9360 CRAN or Bioconductor as long as they are in a git repository. Use
9361 @option{--archive=git} followed by the URL of the git repository:
9364 guix import cran --archive=git https://github.com/immunogenomics/harmony
9370 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
9371 comprehensive TeX archive network for TeX packages that are part of the
9372 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
9374 Information about the package is obtained through the XML API provided
9375 by CTAN, while the source code is downloaded from the SVN repository of
9376 the Tex Live project. This is done because the CTAN does not keep
9379 The command command below imports metadata for the @code{fontspec}
9383 guix import texlive fontspec
9386 When @option{--archive=@var{directory}} is added, the source code is
9387 downloaded not from the @file{latex} sub-directory of the
9388 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
9389 the specified sibling @var{directory} under the same root.
9391 The command below imports metadata for the @code{ifxetex} package from
9392 CTAN while fetching the sources from the directory
9393 @file{texmf/source/generic}:
9396 guix import texlive --archive=generic ifxetex
9400 @cindex JSON, import
9401 Import package metadata from a local JSON file. Consider the following
9402 example package definition in JSON format:
9408 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
9409 "build-system": "gnu",
9410 "home-page": "https://www.gnu.org/software/hello/",
9411 "synopsis": "Hello, GNU world: An example GNU package",
9412 "description": "GNU Hello prints a greeting.",
9413 "license": "GPL-3.0+",
9414 "native-inputs": ["gettext"]
9418 The field names are the same as for the @code{<package>} record
9419 (@xref{Defining Packages}). References to other packages are provided
9420 as JSON lists of quoted package specification strings such as
9421 @code{guile} or @code{guile@@2.0}.
9423 The importer also supports a more explicit source definition using the
9424 common fields for @code{<origin>} records:
9430 "method": "url-fetch",
9431 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
9433 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
9440 The command below reads metadata from the JSON file @code{hello.json}
9441 and outputs a package expression:
9444 guix import json hello.json
9448 Import metadata from a local copy of the source of the
9449 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
9450 relies on the @command{nix-instantiate} command of
9451 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
9452 typically written in a mixture of Nix-language and Bash code. This
9453 command only imports the high-level package structure that is written in
9454 the Nix language. It normally includes all the basic fields of a
9457 When importing a GNU package, the synopsis and descriptions are replaced
9458 by their canonical upstream variant.
9460 Usually, you will first need to do:
9463 export NIX_REMOTE=daemon
9467 so that @command{nix-instantiate} does not try to open the Nix database.
9469 As an example, the command below imports the package definition of
9470 LibreOffice (more precisely, it imports the definition of the package
9471 bound to the @code{libreoffice} top-level attribute):
9474 guix import nix ~/path/to/nixpkgs libreoffice
9479 Import metadata from the Haskell community's central package archive
9480 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
9481 Cabal files and includes all the relevant information, including package
9484 Specific command-line options are:
9489 Read a Cabal file from standard input.
9490 @item --no-test-dependencies
9492 Do not include dependencies required only by the test suites.
9493 @item --cabal-environment=@var{alist}
9494 @itemx -e @var{alist}
9495 @var{alist} is a Scheme alist defining the environment in which the
9496 Cabal conditionals are evaluated. The accepted keys are: @code{os},
9497 @code{arch}, @code{impl} and a string representing the name of a flag.
9498 The value associated with a flag has to be either the symbol
9499 @code{true} or @code{false}. The value associated with other keys
9500 has to conform to the Cabal file format definition. The default value
9501 associated with the keys @code{os}, @code{arch} and @code{impl} is
9502 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
9505 Traverse the dependency graph of the given upstream package recursively
9506 and generate package expressions for all those packages that are not yet
9510 The command below imports metadata for the latest version of the
9511 HTTP Haskell package without including test dependencies and
9512 specifying the value of the flag @samp{network-uri} as @code{false}:
9515 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
9518 A specific package version may optionally be specified by following the
9519 package name by an at-sign and a version number as in the following example:
9522 guix import hackage mtl@@2.1.3.1
9527 The @code{stackage} importer is a wrapper around the @code{hackage} one.
9528 It takes a package name, looks up the package version included in a
9529 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
9530 release and uses the @code{hackage} importer to retrieve its metadata.
9531 Note that it is up to you to select an LTS release compatible with the
9532 GHC compiler used by Guix.
9534 Specific command-line options are:
9537 @item --no-test-dependencies
9539 Do not include dependencies required only by the test suites.
9540 @item --lts-version=@var{version}
9541 @itemx -l @var{version}
9542 @var{version} is the desired LTS release version. If omitted the latest
9546 Traverse the dependency graph of the given upstream package recursively
9547 and generate package expressions for all those packages that are not yet
9551 The command below imports metadata for the HTTP Haskell package
9552 included in the LTS Stackage release version 7.18:
9555 guix import stackage --lts-version=7.18 HTTP
9560 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9561 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9563 Specific command-line options are:
9566 @item --archive=@var{repo}
9567 @itemx -a @var{repo}
9568 @var{repo} identifies the archive repository from which to retrieve the
9569 information. Currently the supported repositories and their identifiers
9573 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9574 identifier. This is the default.
9576 Packages from @code{elpa.gnu.org} are signed with one of the keys
9577 contained in the GnuPG keyring at
9578 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9579 @code{emacs} package (@pxref{Package Installation, ELPA package
9580 signatures,, emacs, The GNU Emacs Manual}).
9583 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9584 @code{melpa-stable} identifier.
9587 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9593 Traverse the dependency graph of the given upstream package recursively
9594 and generate package expressions for all those packages that are not yet
9600 Import metadata from the crates.io Rust package repository
9601 @uref{https://crates.io, crates.io}, as in this example:
9604 guix import crate blake2-rfc
9607 The crate importer also allows you to specify a version string:
9610 guix import crate constant-time-eq@@0.1.0
9613 Additional options include:
9618 Traverse the dependency graph of the given upstream package recursively
9619 and generate package expressions for all those packages that are not yet
9626 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9627 repository used by the OCaml community.
9630 The structure of the @command{guix import} code is modular. It would be
9631 useful to have more importers for other package formats, and your help
9632 is welcome here (@pxref{Contributing}).
9634 @node Invoking guix refresh
9635 @section Invoking @command{guix refresh}
9637 @cindex @command {guix refresh}
9638 The primary audience of the @command{guix refresh} command is developers
9639 of the GNU software distribution. By default, it reports any packages
9640 provided by the distribution that are outdated compared to the latest
9641 upstream version, like this:
9645 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9646 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9649 Alternatively, one can specify packages to consider, in which case a
9650 warning is emitted for packages that lack an updater:
9653 $ guix refresh coreutils guile guile-ssh
9654 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9655 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9658 @command{guix refresh} browses the upstream repository of each package and determines
9659 the highest version number of the releases therein. The command
9660 knows how to update specific types of packages: GNU packages, ELPA
9661 packages, etc.---see the documentation for @option{--type} below. There
9662 are many packages, though, for which it lacks a method to determine
9663 whether a new upstream release is available. However, the mechanism is
9664 extensible, so feel free to get in touch with us to add a new method!
9669 Consider the packages specified, and all the packages upon which they depend.
9672 $ guix refresh --recursive coreutils
9673 gnu/packages/acl.scm:35:2: warning: no updater for acl
9674 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9675 gnu/packages/xml.scm:68:2: warning: no updater for expat
9676 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9682 Sometimes the upstream name differs from the package name used in Guix,
9683 and @command{guix refresh} needs a little help. Most updaters honor the
9684 @code{upstream-name} property in package definitions, which can be used
9688 (define-public network-manager
9690 (name "network-manager")
9692 (properties '((upstream-name . "NetworkManager")))))
9695 When passed @option{--update}, it modifies distribution source files to
9696 update the version numbers and source tarball hashes of those package
9697 recipes (@pxref{Defining Packages}). This is achieved by downloading
9698 each package's latest source tarball and its associated OpenPGP
9699 signature, authenticating the downloaded tarball against its signature
9700 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
9701 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
9704 key used to sign the tarball is missing from the user's keyring, an
9705 attempt is made to automatically retrieve it from a public key server;
9706 when this is successful, the key is added to the user's keyring; otherwise,
9707 @command{guix refresh} reports an error.
9709 The following options are supported:
9713 @item --expression=@var{expr}
9714 @itemx -e @var{expr}
9715 Consider the package @var{expr} evaluates to.
9717 This is useful to precisely refer to a package, as in this example:
9720 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9723 This command lists the dependents of the ``final'' libc (essentially all
9728 Update distribution source files (package recipes) in place. This is
9729 usually run from a checkout of the Guix source tree (@pxref{Running
9730 Guix Before It Is Installed}):
9733 $ ./pre-inst-env guix refresh -s non-core -u
9736 @xref{Defining Packages}, for more information on package definitions.
9738 @item --select=[@var{subset}]
9739 @itemx -s @var{subset}
9740 Select all the packages in @var{subset}, one of @code{core} or
9743 The @code{core} subset refers to all the packages at the core of the
9744 distribution---i.e., packages that are used to build ``everything
9745 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9746 changing one of these packages in the distribution entails a rebuild of
9747 all the others. Thus, such updates are an inconvenience to users in
9748 terms of build time or bandwidth used to achieve the upgrade.
9750 The @code{non-core} subset refers to the remaining packages. It is
9751 typically useful in cases where an update of the core packages would be
9754 @item --manifest=@var{file}
9755 @itemx -m @var{file}
9756 Select all the packages from the manifest in @var{file}. This is useful to
9757 check if any packages of the user manifest can be updated.
9759 @item --type=@var{updater}
9760 @itemx -t @var{updater}
9761 Select only packages handled by @var{updater} (may be a comma-separated
9762 list of updaters). Currently, @var{updater} may be one of:
9766 the updater for GNU packages;
9768 the updater for GNOME packages;
9770 the updater for KDE packages;
9772 the updater for X.org packages;
9774 the updater for packages hosted on kernel.org;
9776 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9778 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9780 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9782 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9784 the updater for @uref{https://pypi.python.org, PyPI} packages.
9786 the updater for @uref{https://rubygems.org, RubyGems} packages.
9788 the updater for @uref{https://github.com, GitHub} packages.
9790 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9792 the updater for @uref{https://www.stackage.org, Stackage} packages.
9794 the updater for @uref{https://crates.io, Crates} packages.
9796 the updater for @uref{https://launchpad.net, Launchpad} packages.
9799 For instance, the following command only checks for updates of Emacs
9800 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9803 $ guix refresh --type=elpa,cran
9804 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9805 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9810 In addition, @command{guix refresh} can be passed one or more package
9811 names, as in this example:
9814 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9818 The command above specifically updates the @code{emacs} and
9819 @code{idutils} packages. The @option{--select} option would have no
9820 effect in this case.
9822 When considering whether to upgrade a package, it is sometimes
9823 convenient to know which packages would be affected by the upgrade and
9824 should be checked for compatibility. For this the following option may
9825 be used when passing @command{guix refresh} one or more package names:
9829 @item --list-updaters
9831 List available updaters and exit (see @option{--type} above).
9833 For each updater, display the fraction of packages it covers; at the
9834 end, display the fraction of packages covered by all these updaters.
9836 @item --list-dependent
9838 List top-level dependent packages that would need to be rebuilt as a
9839 result of upgrading one or more packages.
9841 @xref{Invoking guix graph, the @code{reverse-package} type of
9842 @command{guix graph}}, for information on how to visualize the list of
9843 dependents of a package.
9847 Be aware that the @option{--list-dependent} option only
9848 @emph{approximates} the rebuilds that would be required as a result of
9849 an upgrade. More rebuilds might be required under some circumstances.
9852 $ guix refresh --list-dependent flex
9853 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9854 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9857 The command above lists a set of packages that could be built to check
9858 for compatibility with an upgraded @code{flex} package.
9862 @item --list-transitive
9863 List all the packages which one or more packages depend upon.
9866 $ guix refresh --list-transitive flex
9867 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9868 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{}
9873 The command above lists a set of packages which, when changed, would cause
9874 @code{flex} to be rebuilt.
9876 The following options can be used to customize GnuPG operation:
9880 @item --gpg=@var{command}
9881 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9882 for in @code{$PATH}.
9884 @item --keyring=@var{file}
9885 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9886 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9887 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9888 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9889 information on a tool to manipulate keybox files).
9891 When this option is omitted, @command{guix refresh} uses
9892 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9893 signing keys. OpenPGP signatures are checked against keys from this keyring;
9894 missing keys are downloaded to this keyring as well (see
9895 @option{--key-download} below).
9897 You can export keys from your default GPG keyring into a keybox file using
9898 commands like this one:
9901 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9904 Likewise, you can fetch keys to a specific keybox file like this:
9907 gpg --no-default-keyring --keyring mykeyring.kbx \
9908 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9911 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9912 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9914 @item --key-download=@var{policy}
9915 Handle missing OpenPGP keys according to @var{policy}, which may be one
9920 Always download missing OpenPGP keys from the key server, and add them
9921 to the user's GnuPG keyring.
9924 Never try to download missing OpenPGP keys. Instead just bail out.
9927 When a package signed with an unknown OpenPGP key is encountered, ask
9928 the user whether to download it or not. This is the default behavior.
9931 @item --key-server=@var{host}
9932 Use @var{host} as the OpenPGP key server when importing a public key.
9934 @item --load-path=@var{directory}
9935 Add @var{directory} to the front of the package module search path
9936 (@pxref{Package Modules}).
9938 This allows users to define their own packages and make them visible to
9939 the command-line tools.
9943 The @code{github} updater uses the
9944 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9945 releases. When used repeatedly e.g.@: when refreshing all packages,
9946 GitHub will eventually refuse to answer any further API requests. By
9947 default 60 API requests per hour are allowed, and a full refresh on all
9948 GitHub packages in Guix requires more than this. Authentication with
9949 GitHub through the use of an API token alleviates these limits. To use
9950 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
9951 token procured from @uref{https://github.com/settings/tokens} or
9955 @node Invoking guix lint
9956 @section Invoking @command{guix lint}
9958 @cindex @command{guix lint}
9959 @cindex package, checking for errors
9960 The @command{guix lint} command is meant to help package developers avoid
9961 common errors and use a consistent style. It runs a number of checks on
9962 a given set of packages in order to find common mistakes in their
9963 definitions. Available @dfn{checkers} include (see
9964 @option{--list-checkers} for a complete list):
9969 Validate certain typographical and stylistic rules about package
9970 descriptions and synopses.
9972 @item inputs-should-be-native
9973 Identify inputs that should most likely be native inputs.
9979 @itemx source-file-name
9980 Probe @code{home-page} and @code{source} URLs and report those that are
9981 invalid. Suggest a @code{mirror://} URL when applicable. If the
9982 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9983 URL. Check that the source file name is meaningful, e.g.@: is not just a
9984 version number or ``git-checkout'', without a declared @code{file-name}
9985 (@pxref{origin Reference}).
9987 @item source-unstable-tarball
9988 Parse the @code{source} URL to determine if a tarball from GitHub is
9989 autogenerated or if it is a release tarball. Unfortunately GitHub's
9990 autogenerated tarballs are sometimes regenerated.
9993 Check that the derivation of the given packages can be successfully
9994 computed for all the supported systems (@pxref{Derivations}).
9996 @item profile-collisions
9997 Check whether installing the given packages in a profile would lead to
9998 collisions. Collisions occur when several packages with the same name
9999 but a different version or a different store file name are propagated.
10000 @xref{package Reference, @code{propagated-inputs}}, for more information
10001 on propagated inputs.
10004 @cindex Software Heritage, source code archive
10005 @cindex archival of source code, Software Heritage
10006 Checks whether the package's source code is archived at
10007 @uref{https://www.softwareheritage.org, Software Heritage}.
10009 When the source code that is not archived comes from a version-control system
10010 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
10011 ``save'' request so that it eventually archives it. This ensures that the
10012 source will remain available in the long term, and that Guix can fall back to
10013 Software Heritage should the source code disappear from its original host.
10014 The status of recent ``save'' requests can be
10015 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
10017 When source code is a tarball obtained with @code{url-fetch}, simply print a
10018 message when it is not archived. As of this writing, Software Heritage does
10019 not allow requests to save arbitrary tarballs; we are working on ways to
10020 ensure that non-VCS source code is also archived.
10023 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
10024 request rate per IP address}. When the limit is reached, @command{guix lint}
10025 prints a message and the @code{archival} checker stops doing anything until
10026 that limit has been reset.
10029 @cindex security vulnerabilities
10030 @cindex CVE, Common Vulnerabilities and Exposures
10031 Report known vulnerabilities found in the Common Vulnerabilities and
10032 Exposures (CVE) databases of the current and past year
10033 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
10036 To view information about a particular vulnerability, visit pages such as:
10040 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
10042 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
10046 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
10047 @code{CVE-2015-7554}.
10049 Package developers can specify in package recipes the
10050 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
10051 name and version of the package when they differ from the name or version
10052 that Guix uses, as in this example:
10058 ;; CPE calls this package "grub2".
10059 (properties '((cpe-name . "grub2")
10060 (cpe-version . "2.3"))))
10063 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
10064 Some entries in the CVE database do not specify which version of a
10065 package they apply to, and would thus ``stick around'' forever. Package
10066 developers who found CVE alerts and verified they can be ignored can
10067 declare them as in this example:
10073 ;; These CVEs no longer apply and can be safely ignored.
10074 (properties `((lint-hidden-cve . ("CVE-2011-0433"
10077 "CVE-2011-5244")))))
10081 Warn about obvious source code formatting issues: trailing white space,
10082 use of tabulations, etc.
10085 The general syntax is:
10088 guix lint @var{options} @var{package}@dots{}
10091 If no package is given on the command line, then all packages are checked.
10092 The @var{options} may be zero or more of the following:
10095 @item --list-checkers
10097 List and describe all the available checkers that will be run on packages
10102 Only enable the checkers specified in a comma-separated list using the
10103 names returned by @option{--list-checkers}.
10105 @item --load-path=@var{directory}
10106 @itemx -L @var{directory}
10107 Add @var{directory} to the front of the package module search path
10108 (@pxref{Package Modules}).
10110 This allows users to define their own packages and make them visible to
10111 the command-line tools.
10115 @node Invoking guix size
10116 @section Invoking @command{guix size}
10119 @cindex package size
10121 @cindex @command{guix size}
10122 The @command{guix size} command helps package developers profile the
10123 disk usage of packages. It is easy to overlook the impact of an
10124 additional dependency added to a package, or the impact of using a
10125 single output for a package that could easily be split (@pxref{Packages
10126 with Multiple Outputs}). Such are the typical issues that
10127 @command{guix size} can highlight.
10129 The command can be passed one or more package specifications
10130 such as @code{gcc@@4.8}
10131 or @code{guile:debug}, or a file name in the store. Consider this
10135 $ guix size coreutils
10136 store item total self
10137 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
10138 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
10139 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
10140 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
10141 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
10142 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
10143 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
10144 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
10149 The store items listed here constitute the @dfn{transitive closure} of
10150 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
10151 would be returned by:
10154 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
10157 Here the output shows three columns next to store items. The first column,
10158 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
10159 the store item---that is, its own size plus the size of all its
10160 dependencies. The next column, labeled ``self'', shows the size of the
10161 item itself. The last column shows the ratio of the size of the item
10162 itself to the space occupied by all the items listed here.
10164 In this example, we see that the closure of Coreutils weighs in at
10165 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
10166 libraries. (That libc and GCC's libraries represent a large fraction of
10167 the closure is not a problem @i{per se} because they are always available
10168 on the system anyway.)
10170 Since the command also accepts store file names, assessing the size of
10171 a build result is straightforward:
10174 guix size $(guix system build config.scm)
10177 When the package(s) passed to @command{guix size} are available in the
10178 store@footnote{More precisely, @command{guix size} looks for the
10179 @emph{ungrafted} variant of the given package(s), as returned by
10180 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
10181 for information on grafts.}, @command{guix size} queries the daemon to determine its
10182 dependencies, and measures its size in the store, similar to @command{du
10183 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
10186 When the given packages are @emph{not} in the store, @command{guix size}
10187 reports information based on the available substitutes
10188 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
10189 store items that are not even on disk, only available remotely.
10191 You can also specify several package names:
10194 $ guix size coreutils grep sed bash
10195 store item total self
10196 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
10197 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
10198 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
10199 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
10205 In this example we see that the combination of the four packages takes
10206 102.3@tie{}MiB in total, which is much less than the sum of each closure
10207 since they have a lot of dependencies in common.
10209 When looking at the profile returned by @command{guix size}, you may
10210 find yourself wondering why a given package shows up in the profile at
10211 all. To understand it, you can use @command{guix graph --path -t
10212 references} to display the shortest path between the two packages
10213 (@pxref{Invoking guix graph}).
10215 The available options are:
10219 @item --substitute-urls=@var{urls}
10220 Use substitute information from @var{urls}.
10221 @xref{client-substitute-urls, the same option for @code{guix build}}.
10223 @item --sort=@var{key}
10224 Sort lines according to @var{key}, one of the following options:
10228 the size of each item (the default);
10230 the total size of the item's closure.
10233 @item --map-file=@var{file}
10234 Write a graphical map of disk usage in PNG format to @var{file}.
10236 For the example above, the map looks like this:
10238 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
10239 produced by @command{guix size}}
10241 This option requires that
10242 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
10243 installed and visible in Guile's module search path. When that is not
10244 the case, @command{guix size} fails as it tries to load it.
10246 @item --system=@var{system}
10247 @itemx -s @var{system}
10248 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
10250 @item --load-path=@var{directory}
10251 @itemx -L @var{directory}
10252 Add @var{directory} to the front of the package module search path
10253 (@pxref{Package Modules}).
10255 This allows users to define their own packages and make them visible to
10256 the command-line tools.
10259 @node Invoking guix graph
10260 @section Invoking @command{guix graph}
10263 @cindex @command{guix graph}
10264 @cindex package dependencies
10265 Packages and their dependencies form a @dfn{graph}, specifically a
10266 directed acyclic graph (DAG). It can quickly become difficult to have a
10267 mental model of the package DAG, so the @command{guix graph} command
10268 provides a visual representation of the DAG. By default,
10269 @command{guix graph} emits a DAG representation in the input format of
10270 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
10271 directly to the @command{dot} command of Graphviz. It can also emit an
10272 HTML page with embedded JavaScript code to display a ``chord diagram''
10273 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
10274 emit Cypher queries to construct a graph in a graph database supporting
10275 the @uref{https://www.opencypher.org/, openCypher} query language. With
10276 @option{--path}, it simply displays the shortest path between two
10277 packages. The general syntax is:
10280 guix graph @var{options} @var{package}@dots{}
10283 For example, the following command generates a PDF file representing the
10284 package DAG for the GNU@tie{}Core Utilities, showing its build-time
10288 guix graph coreutils | dot -Tpdf > dag.pdf
10291 The output looks like this:
10293 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
10295 Nice little graph, no?
10297 You may find it more pleasant to navigate the graph interactively with
10298 @command{xdot} (from the @code{xdot} package):
10301 guix graph coreutils | xdot -
10304 But there is more than one graph! The one above is concise: it is the
10305 graph of package objects, omitting implicit inputs such as GCC, libc,
10306 grep, etc. It is often useful to have such a concise graph, but
10307 sometimes one may want to see more details. @command{guix graph} supports
10308 several types of graphs, allowing you to choose the level of detail:
10312 This is the default type used in the example above. It shows the DAG of
10313 package objects, excluding implicit dependencies. It is concise, but
10314 filters out many details.
10316 @item reverse-package
10317 This shows the @emph{reverse} DAG of packages. For example:
10320 guix graph --type=reverse-package ocaml
10323 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
10324 you are also interested in cases where OCaml is an implicit dependency, see
10325 @code{reverse-bag} below).
10327 Note that for core packages this can yield huge graphs. If all you want
10328 is to know the number of packages that depend on a given package, use
10329 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
10330 @option{--list-dependent}}).
10333 This is the package DAG, @emph{including} implicit inputs.
10335 For instance, the following command:
10338 guix graph --type=bag-emerged coreutils
10341 ...@: yields this bigger graph:
10343 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
10345 At the bottom of the graph, we see all the implicit inputs of
10346 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
10348 Now, note that the dependencies of these implicit inputs---that is, the
10349 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
10350 here, for conciseness.
10353 Similar to @code{bag-emerged}, but this time including all the bootstrap
10356 @item bag-with-origins
10357 Similar to @code{bag}, but also showing origins and their dependencies.
10360 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
10361 it also takes implicit dependencies into account. For example:
10364 guix graph -t reverse-bag dune
10368 ...@: yields the graph of all packages that depend on Dune, directly or
10369 indirectly. Since Dune is an @emph{implicit} dependency of many packages
10370 @i{via} @code{dune-build-system}, this shows a large number of packages,
10371 whereas @code{reverse-package} would show very few if any.
10374 This is the most detailed representation: It shows the DAG of
10375 derivations (@pxref{Derivations}) and plain store items. Compared to
10376 the above representation, many additional nodes are visible, including
10377 build scripts, patches, Guile modules, etc.
10379 For this type of graph, it is also possible to pass a @file{.drv} file
10380 name instead of a package name, as in:
10383 guix graph -t derivation `guix system build -d my-config.scm`
10387 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
10388 For example, the following command shows the graph for the package
10389 module that defines the @code{guile} package:
10392 guix graph -t module guile | xdot -
10396 All the types above correspond to @emph{build-time dependencies}. The
10397 following graph type represents the @emph{run-time dependencies}:
10401 This is the graph of @dfn{references} of a package output, as returned
10402 by @command{guix gc --references} (@pxref{Invoking guix gc}).
10404 If the given package output is not available in the store, @command{guix
10405 graph} attempts to obtain dependency information from substitutes.
10407 Here you can also pass a store file name instead of a package name. For
10408 example, the command below produces the reference graph of your profile
10409 (which can be big!):
10412 guix graph -t references `readlink -f ~/.guix-profile`
10416 This is the graph of the @dfn{referrers} of a store item, as returned by
10417 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
10419 This relies exclusively on local information from your store. For
10420 instance, let us suppose that the current Inkscape is available in 10
10421 profiles on your machine; @command{guix graph -t referrers inkscape}
10422 will show a graph rooted at Inkscape and with those 10 profiles linked
10425 It can help determine what is preventing a store item from being garbage
10430 @cindex shortest path, between packages
10431 Often, the graph of the package you are interested in does not fit on
10432 your screen, and anyway all you want to know is @emph{why} that package
10433 actually depends on some seemingly unrelated package. The
10434 @option{--path} option instructs @command{guix graph} to display the
10435 shortest path between two packages (or derivations, or store items,
10439 $ guix graph --path emacs libunistring
10442 libunistring@@0.9.10
10443 $ guix graph --path -t derivation emacs libunistring
10444 /gnu/store/@dots{}-emacs-26.3.drv
10445 /gnu/store/@dots{}-mailutils-3.9.drv
10446 /gnu/store/@dots{}-libunistring-0.9.10.drv
10447 $ guix graph --path -t references emacs libunistring
10448 /gnu/store/@dots{}-emacs-26.3
10449 /gnu/store/@dots{}-libidn2-2.2.0
10450 /gnu/store/@dots{}-libunistring-0.9.10
10453 The available options are the following:
10456 @item --type=@var{type}
10457 @itemx -t @var{type}
10458 Produce a graph output of @var{type}, where @var{type} must be one of
10459 the values listed above.
10462 List the supported graph types.
10464 @item --backend=@var{backend}
10465 @itemx -b @var{backend}
10466 Produce a graph using the selected @var{backend}.
10468 @item --list-backends
10469 List the supported graph backends.
10471 Currently, the available backends are Graphviz and d3.js.
10474 Display the shortest path between two nodes of the type specified by
10475 @option{--type}. The example below shows the shortest path between
10476 @code{libreoffice} and @code{llvm} according to the references of
10477 @code{libreoffice}:
10480 $ guix graph --path -t references libreoffice llvm
10481 /gnu/store/@dots{}-libreoffice-6.4.2.2
10482 /gnu/store/@dots{}-libepoxy-1.5.4
10483 /gnu/store/@dots{}-mesa-19.3.4
10484 /gnu/store/@dots{}-llvm-9.0.1
10487 @item --expression=@var{expr}
10488 @itemx -e @var{expr}
10489 Consider the package @var{expr} evaluates to.
10491 This is useful to precisely refer to a package, as in this example:
10494 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
10497 @item --system=@var{system}
10498 @itemx -s @var{system}
10499 Display the graph for @var{system}---e.g., @code{i686-linux}.
10501 The package dependency graph is largely architecture-independent, but there
10502 are some architecture-dependent bits that this option allows you to visualize.
10504 @item --load-path=@var{directory}
10505 @itemx -L @var{directory}
10506 Add @var{directory} to the front of the package module search path
10507 (@pxref{Package Modules}).
10509 This allows users to define their own packages and make them visible to
10510 the command-line tools.
10513 On top of that, @command{guix graph} supports all the usual package
10514 transformation options (@pxref{Package Transformation Options}). This
10515 makes it easy to view the effect of a graph-rewriting transformation
10516 such as @option{--with-input}. For example, the command below outputs
10517 the graph of @code{git} once @code{openssl} has been replaced by
10518 @code{libressl} everywhere in the graph:
10521 guix graph git --with-input=openssl=libressl
10524 So many possibilities, so much fun!
10526 @node Invoking guix publish
10527 @section Invoking @command{guix publish}
10529 @cindex @command{guix publish}
10530 The purpose of @command{guix publish} is to enable users to easily share
10531 their store with others, who can then use it as a substitute server
10532 (@pxref{Substitutes}).
10534 When @command{guix publish} runs, it spawns an HTTP server which allows
10535 anyone with network access to obtain substitutes from it. This means
10536 that any machine running Guix can also act as if it were a build farm,
10537 since the HTTP interface is compatible with Cuirass, the software behind
10538 the @code{@value{SUBSTITUTE-SERVER}} build farm.
10540 For security, each substitute is signed, allowing recipients to check
10541 their authenticity and integrity (@pxref{Substitutes}). Because
10542 @command{guix publish} uses the signing key of the system, which is only
10543 readable by the system administrator, it must be started as root; the
10544 @option{--user} option makes it drop root privileges early on.
10546 The signing key pair must be generated before @command{guix publish} is
10547 launched, using @command{guix archive --generate-key} (@pxref{Invoking
10550 The general syntax is:
10553 guix publish @var{options}@dots{}
10556 Running @command{guix publish} without any additional arguments will
10557 spawn an HTTP server on port 8080:
10563 Once a publishing server has been authorized (@pxref{Invoking guix
10564 archive}), the daemon may download substitutes from it:
10567 guix-daemon --substitute-urls=http://example.org:8080
10570 By default, @command{guix publish} compresses archives on the fly as it
10571 serves them. This ``on-the-fly'' mode is convenient in that it requires
10572 no setup and is immediately available. However, when serving lots of
10573 clients, we recommend using the @option{--cache} option, which enables
10574 caching of the archives before they are sent to clients---see below for
10575 details. The @command{guix weather} command provides a handy way to
10576 check what a server provides (@pxref{Invoking guix weather}).
10578 As a bonus, @command{guix publish} also serves as a content-addressed
10579 mirror for source files referenced in @code{origin} records
10580 (@pxref{origin Reference}). For instance, assuming @command{guix
10581 publish} is running on @code{example.org}, the following URL returns the
10582 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
10583 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
10586 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
10589 Obviously, these URLs only work for files that are in the store; in
10590 other cases, they return 404 (``Not Found'').
10592 @cindex build logs, publication
10593 Build logs are available from @code{/log} URLs like:
10596 http://example.org/log/gwspk@dots{}-guile-2.2.3
10600 When @command{guix-daemon} is configured to save compressed build logs,
10601 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
10602 URLs return the compressed log as-is, with an appropriate
10603 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
10604 running @command{guix-daemon} with @option{--log-compression=gzip} since
10605 Web browsers can automatically decompress it, which is not the case with
10608 The following options are available:
10611 @item --port=@var{port}
10612 @itemx -p @var{port}
10613 Listen for HTTP requests on @var{port}.
10615 @item --listen=@var{host}
10616 Listen on the network interface for @var{host}. The default is to
10617 accept connections from any interface.
10619 @item --user=@var{user}
10620 @itemx -u @var{user}
10621 Change privileges to @var{user} as soon as possible---i.e., once the
10622 server socket is open and the signing key has been read.
10624 @item --compression[=@var{method}[:@var{level}]]
10625 @itemx -C [@var{method}[:@var{level}]]
10626 Compress data using the given @var{method} and @var{level}. @var{method} is
10627 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
10630 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
10631 to different compression levels: 1 is the fastest, and 9 is the best
10632 (CPU-intensive). The default is 3.
10634 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
10635 increase in CPU usage; see
10636 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
10639 Unless @option{--cache} is used, compression occurs on the fly and
10640 the compressed streams are not
10641 cached. Thus, to reduce load on the machine that runs @command{guix
10642 publish}, it may be a good idea to choose a low compression level, to
10643 run @command{guix publish} behind a caching proxy, or to use
10644 @option{--cache}. Using @option{--cache} has the advantage that it
10645 allows @command{guix publish} to add @code{Content-Length} HTTP header
10648 This option can be repeated, in which case every substitute gets compressed
10649 using all the selected methods, and all of them are advertised. This is
10650 useful when users may not support all the compression methods: they can select
10651 the one they support.
10653 @item --cache=@var{directory}
10654 @itemx -c @var{directory}
10655 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
10656 and only serve archives that are in cache.
10658 When this option is omitted, archives and meta-data are created
10659 on-the-fly. This can reduce the available bandwidth, especially when
10660 compression is enabled, since this may become CPU-bound. Another
10661 drawback of the default mode is that the length of archives is not known
10662 in advance, so @command{guix publish} does not add a
10663 @code{Content-Length} HTTP header to its responses, which in turn
10664 prevents clients from knowing the amount of data being downloaded.
10666 Conversely, when @option{--cache} is used, the first request for a store
10667 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10668 background process to @dfn{bake} the archive---computing its
10669 @code{.narinfo} and compressing the archive, if needed. Once the
10670 archive is cached in @var{directory}, subsequent requests succeed and
10671 are served directly from the cache, which guarantees that clients get
10672 the best possible bandwidth.
10674 The ``baking'' process is performed by worker threads. By default, one
10675 thread per CPU core is created, but this can be customized. See
10676 @option{--workers} below.
10678 When @option{--ttl} is used, cached entries are automatically deleted
10679 when they have expired.
10681 @item --workers=@var{N}
10682 When @option{--cache} is used, request the allocation of @var{N} worker
10683 threads to ``bake'' archives.
10685 @item --ttl=@var{ttl}
10686 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10687 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10688 days, @code{1m} means 1 month, and so on.
10690 This allows the user's Guix to keep substitute information in cache for
10691 @var{ttl}. However, note that @code{guix publish} does not itself
10692 guarantee that the store items it provides will indeed remain available
10693 for as long as @var{ttl}.
10695 Additionally, when @option{--cache} is used, cached entries that have
10696 not been accessed for @var{ttl} and that no longer have a corresponding
10697 item in the store, may be deleted.
10699 @item --nar-path=@var{path}
10700 Use @var{path} as the prefix for the URLs of ``nar'' files
10701 (@pxref{Invoking guix archive, normalized archives}).
10703 By default, nars are served at a URL such as
10704 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
10705 change the @code{/nar} part to @var{path}.
10707 @item --public-key=@var{file}
10708 @itemx --private-key=@var{file}
10709 Use the specific @var{file}s as the public/private key pair used to sign
10710 the store items being published.
10712 The files must correspond to the same key pair (the private key is used
10713 for signing and the public key is merely advertised in the signature
10714 metadata). They must contain keys in the canonical s-expression format
10715 as produced by @command{guix archive --generate-key} (@pxref{Invoking
10716 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
10717 @file{/etc/guix/signing-key.sec} are used.
10719 @item --repl[=@var{port}]
10720 @itemx -r [@var{port}]
10721 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
10722 Reference Manual}) on @var{port} (37146 by default). This is used
10723 primarily for debugging a running @command{guix publish} server.
10726 Enabling @command{guix publish} on Guix System is a one-liner: just
10727 instantiate a @code{guix-publish-service-type} service in the @code{services} field
10728 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
10729 @code{guix-publish-service-type}}).
10731 If you are instead running Guix on a ``foreign distro'', follow these
10736 If your host distro uses the systemd init system:
10739 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
10740 /etc/systemd/system/
10741 # systemctl start guix-publish && systemctl enable guix-publish
10745 If your host distro uses the Upstart init system:
10748 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
10749 # start guix-publish
10753 Otherwise, proceed similarly with your distro's init system.
10756 @node Invoking guix challenge
10757 @section Invoking @command{guix challenge}
10759 @cindex reproducible builds
10760 @cindex verifiable builds
10761 @cindex @command{guix challenge}
10763 Do the binaries provided by this server really correspond to the source
10764 code it claims to build? Is a package build process deterministic?
10765 These are the questions the @command{guix challenge} command attempts to
10768 The former is obviously an important question: Before using a substitute
10769 server (@pxref{Substitutes}), one had better @emph{verify} that it
10770 provides the right binaries, and thus @emph{challenge} it. The latter
10771 is what enables the former: If package builds are deterministic, then
10772 independent builds of the package should yield the exact same result,
10773 bit for bit; if a server provides a binary different from the one
10774 obtained locally, it may be either corrupt or malicious.
10776 We know that the hash that shows up in @file{/gnu/store} file names is
10777 the hash of all the inputs of the process that built the file or
10778 directory---compilers, libraries, build scripts,
10779 etc. (@pxref{Introduction}). Assuming deterministic build processes,
10780 one store file name should map to exactly one build output.
10781 @command{guix challenge} checks whether there is, indeed, a single
10782 mapping by comparing the build outputs of several independent builds of
10783 any given store item.
10785 The command output looks like this:
10788 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10789 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
10790 updating list of substitutes from 'https://guix.example.org'... 100.0%
10791 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
10792 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10793 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10794 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
10796 /lib/libcrypto.so.1.1
10799 /gnu/store/@dots{}-git-2.5.0 contents differ:
10800 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
10801 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
10802 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
10804 /libexec/git-core/git-fsck
10806 /gnu/store/@dots{}-pius-2.1.1 contents differ:
10807 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10808 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10809 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
10811 /share/man/man1/pius.1.gz
10815 6,406 store items were analyzed:
10816 - 4,749 (74.1%) were identical
10817 - 525 (8.2%) differed
10818 - 1,132 (17.7%) were inconclusive
10822 In this example, @command{guix challenge} first scans the store to
10823 determine the set of locally-built derivations---as opposed to store
10824 items that were downloaded from a substitute server---and then queries
10825 all the substitute servers. It then reports those store items for which
10826 the servers obtained a result different from the local build.
10828 @cindex non-determinism, in package builds
10829 As an example, @code{guix.example.org} always gets a different answer.
10830 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10831 case of Git. This might indicate that the build process of Git is
10832 non-deterministic, meaning that its output varies as a function of
10833 various things that Guix does not fully control, in spite of building
10834 packages in isolated environments (@pxref{Features}). Most common
10835 sources of non-determinism include the addition of timestamps in build
10836 results, the inclusion of random numbers, and directory listings sorted
10837 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
10840 To find out what is wrong with this Git binary, the easiest approach is
10844 guix challenge git \
10845 --diff=diffoscope \
10846 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10849 This automatically invokes @command{diffoscope}, which displays detailed
10850 information about files that differ.
10852 Alternatively, we can do something along these lines (@pxref{Invoking guix
10856 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
10857 | lzip -d | guix archive -x /tmp/git
10858 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
10861 This command shows the difference between the files resulting from the
10862 local build, and the files resulting from the build on
10863 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
10864 diffutils, Comparing and Merging Files}). The @command{diff} command
10865 works great for text files. When binary files differ, a better option
10866 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
10867 visualize differences for all kinds of files.
10869 Once you have done that work, you can tell whether the differences are due
10870 to a non-deterministic build process or to a malicious server. We try
10871 hard to remove sources of non-determinism in packages to make it easier
10872 to verify substitutes, but of course, this is a process that
10873 involves not just Guix, but a large part of the free software community.
10874 In the meantime, @command{guix challenge} is one tool to help address
10877 If you are writing packages for Guix, you are encouraged to check
10878 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
10879 same build result as you did with:
10882 $ guix challenge @var{package}
10886 where @var{package} is a package specification such as
10887 @code{guile@@2.0} or @code{glibc:debug}.
10889 The general syntax is:
10892 guix challenge @var{options} [@var{packages}@dots{}]
10895 When a difference is found between the hash of a locally-built item and
10896 that of a server-provided substitute, or among substitutes provided by
10897 different servers, the command displays it as in the example above and
10898 its exit code is 2 (other non-zero exit codes denote other kinds of
10901 The one option that matters is:
10905 @item --substitute-urls=@var{urls}
10906 Consider @var{urls} the whitespace-separated list of substitute source
10907 URLs to compare to.
10909 @item --diff=@var{mode}
10910 Upon mismatches, show differences according to @var{mode}, one of:
10913 @item @code{simple} (the default)
10914 Show the list of files that differ.
10916 @item @code{diffoscope}
10917 @itemx @var{command}
10918 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
10919 two directories whose contents do not match.
10921 When @var{command} is an absolute file name, run @var{command} instead
10925 Do not show further details about the differences.
10928 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
10929 downloads the store items from the given substitute servers so that it
10934 Show details about matches (identical contents) in addition to
10935 information about mismatches.
10939 @node Invoking guix copy
10940 @section Invoking @command{guix copy}
10942 @cindex copy, of store items, over SSH
10943 @cindex SSH, copy of store items
10944 @cindex sharing store items across machines
10945 @cindex transferring store items across machines
10946 The @command{guix copy} command copies items from the store of one
10947 machine to that of another machine over a secure shell (SSH)
10948 connection@footnote{This command is available only when Guile-SSH was
10949 found. @xref{Requirements}, for details.}. For example, the following
10950 command copies the @code{coreutils} package, the user's profile, and all
10951 their dependencies over to @var{host}, logged in as @var{user}:
10954 guix copy --to=@var{user}@@@var{host} \
10955 coreutils `readlink -f ~/.guix-profile`
10958 If some of the items to be copied are already present on @var{host},
10959 they are not actually sent.
10961 The command below retrieves @code{libreoffice} and @code{gimp} from
10962 @var{host}, assuming they are available there:
10965 guix copy --from=@var{host} libreoffice gimp
10968 The SSH connection is established using the Guile-SSH client, which is
10969 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10970 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10972 The key used to sign items that are sent must be accepted by the remote
10973 machine. Likewise, the key used by the remote machine to sign items you
10974 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10975 own daemon. @xref{Invoking guix archive}, for more information about
10976 store item authentication.
10978 The general syntax is:
10981 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10984 You must always specify one of the following options:
10987 @item --to=@var{spec}
10988 @itemx --from=@var{spec}
10989 Specify the host to send to or receive from. @var{spec} must be an SSH
10990 spec such as @code{example.org}, @code{charlie@@example.org}, or
10991 @code{charlie@@example.org:2222}.
10994 The @var{items} can be either package names, such as @code{gimp}, or
10995 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10997 When specifying the name of a package to send, it is first built if
10998 needed, unless @option{--dry-run} was specified. Common build options
10999 are supported (@pxref{Common Build Options}).
11002 @node Invoking guix container
11003 @section Invoking @command{guix container}
11005 @cindex @command{guix container}
11007 As of version @value{VERSION}, this tool is experimental. The interface
11008 is subject to radical change in the future.
11011 The purpose of @command{guix container} is to manipulate processes
11012 running within an isolated environment, commonly known as a
11013 ``container'', typically created by the @command{guix environment}
11014 (@pxref{Invoking guix environment}) and @command{guix system container}
11015 (@pxref{Invoking guix system}) commands.
11017 The general syntax is:
11020 guix container @var{action} @var{options}@dots{}
11023 @var{action} specifies the operation to perform with a container, and
11024 @var{options} specifies the context-specific arguments for the action.
11026 The following actions are available:
11030 Execute a command within the context of a running container.
11035 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
11038 @var{pid} specifies the process ID of the running container.
11039 @var{program} specifies an executable file name within the root file
11040 system of the container. @var{arguments} are the additional options that
11041 will be passed to @var{program}.
11043 The following command launches an interactive login shell inside a
11044 Guix system container, started by @command{guix system container}, and whose
11045 process ID is 9001:
11048 guix container exec 9001 /run/current-system/profile/bin/bash --login
11051 Note that the @var{pid} cannot be the parent process of a container. It
11052 must be PID 1 of the container or one of its child processes.
11056 @node Invoking guix weather
11057 @section Invoking @command{guix weather}
11059 Occasionally you're grumpy because substitutes are lacking and you end
11060 up building packages by yourself (@pxref{Substitutes}). The
11061 @command{guix weather} command reports on substitute availability on the
11062 specified servers so you can have an idea of whether you'll be grumpy
11063 today. It can sometimes be useful info as a user, but it is primarily
11064 useful to people running @command{guix publish} (@pxref{Invoking guix
11067 @cindex statistics, for substitutes
11068 @cindex availability of substitutes
11069 @cindex substitute availability
11070 @cindex weather, substitute availability
11071 Here's a sample run:
11074 $ guix weather --substitute-urls=https://guix.example.org
11075 computing 5,872 package derivations for x86_64-linux...
11076 looking for 6,128 store items on https://guix.example.org..
11077 updating list of substitutes from 'https://guix.example.org'... 100.0%
11078 https://guix.example.org
11079 43.4% substitutes available (2,658 out of 6,128)
11080 7,032.5 MiB of nars (compressed)
11081 19,824.2 MiB on disk (uncompressed)
11082 0.030 seconds per request (182.9 seconds in total)
11083 33.5 requests per second
11085 9.8% (342 out of 3,470) of the missing items are queued
11087 x86_64-linux: 518 (59.7%)
11088 i686-linux: 221 (25.5%)
11089 aarch64-linux: 128 (14.8%)
11090 build rate: 23.41 builds per hour
11091 x86_64-linux: 11.16 builds per hour
11092 i686-linux: 6.03 builds per hour
11093 aarch64-linux: 6.41 builds per hour
11096 @cindex continuous integration, statistics
11097 As you can see, it reports the fraction of all the packages for which
11098 substitutes are available on the server---regardless of whether
11099 substitutes are enabled, and regardless of whether this server's signing
11100 key is authorized. It also reports the size of the compressed archives
11101 (``nars'') provided by the server, the size the corresponding store
11102 items occupy in the store (assuming deduplication is turned off), and
11103 the server's throughput. The second part gives continuous integration
11104 (CI) statistics, if the server supports it. In addition, using the
11105 @option{--coverage} option, @command{guix weather} can list ``important''
11106 package substitutes missing on the server (see below).
11108 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
11109 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
11110 challenge}, it ignores signatures on those substitutes, which is
11111 innocuous since the command only gathers statistics and cannot install
11114 The general syntax is:
11117 guix weather @var{options}@dots{} [@var{packages}@dots{}]
11120 When @var{packages} is omitted, @command{guix weather} checks the availability
11121 of substitutes for @emph{all} the packages, or for those specified with
11122 @option{--manifest}; otherwise it only considers the specified packages. It
11123 is also possible to query specific system types with @option{--system}.
11124 @command{guix weather} exits with a non-zero code when the fraction of
11125 available substitutes is below 100%.
11127 The available options are listed below.
11130 @item --substitute-urls=@var{urls}
11131 @var{urls} is the space-separated list of substitute server URLs to
11132 query. When this option is omitted, the default set of substitute
11133 servers is queried.
11135 @item --system=@var{system}
11136 @itemx -s @var{system}
11137 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
11138 option can be repeated, in which case @command{guix weather} will query
11139 substitutes for several system types.
11141 @item --manifest=@var{file}
11142 Instead of querying substitutes for all the packages, only ask for those
11143 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
11144 with the @code{-m} option of @command{guix package} (@pxref{Invoking
11147 This option can be repeated several times, in which case the manifests
11150 @item --coverage[=@var{count}]
11151 @itemx -c [@var{count}]
11152 Report on substitute coverage for packages: list packages with at least
11153 @var{count} dependents (zero by default) for which substitutes are
11154 unavailable. Dependent packages themselves are not listed: if @var{b} depends
11155 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
11156 @var{b} usually lacks substitutes as well. The result looks like this:
11159 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
11160 computing 8,983 package derivations for x86_64-linux...
11161 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
11162 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
11163 @value{SUBSTITUTE-URL}
11164 64.7% substitutes available (6,047 out of 9,343)
11166 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
11167 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
11168 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
11169 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
11173 What this example shows is that @code{kcoreaddons} and presumably the 58
11174 packages that depend on it have no substitutes at @code{ci.guix.info};
11175 likewise for @code{qgpgme} and the 46 packages that depend on it.
11177 If you are a Guix developer, or if you are taking care of this build farm,
11178 you'll probably want to have a closer look at these packages: they may simply
11181 @item --display-missing
11182 Display the list of store items for which substitutes are missing.
11185 @node Invoking guix processes
11186 @section Invoking @command{guix processes}
11188 The @command{guix processes} command can be useful to developers and system
11189 administrators, especially on multi-user machines and on build farms: it lists
11190 the current sessions (connections to the daemon), as well as information about
11191 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
11192 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
11193 listed.}. Here's an example of the information it returns:
11196 $ sudo guix processes
11199 ClientCommand: guix environment --ad-hoc python
11203 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
11207 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
11208 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
11209 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
11210 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
11211 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
11212 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
11213 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
11216 In this example we see that @command{guix-daemon} has three clients:
11217 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
11218 integration tool; their process identifier (PID) is given by the
11219 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
11220 @command{guix-daemon} sub-process of this particular session.
11222 The @code{LockHeld} fields show which store items are currently locked by this
11223 session, which corresponds to store items being built or substituted (the
11224 @code{LockHeld} field is not displayed when @command{guix processes} is not
11225 running as root). Last, by looking at the @code{ChildProcess} field, we
11226 understand that these three builds are being offloaded (@pxref{Daemon Offload
11229 The output is in Recutils format so we can use the handy @command{recsel}
11230 command to select sessions of interest (@pxref{Selection Expressions,,,
11231 recutils, GNU recutils manual}). As an example, the command shows the command
11232 line and PID of the client that triggered the build of a Perl package:
11235 $ sudo guix processes | \
11236 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
11238 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
11241 @node System Configuration
11242 @chapter System Configuration
11244 @cindex system configuration
11245 Guix System supports a consistent whole-system configuration
11246 mechanism. By that we mean that all aspects of the global system
11247 configuration---such as the available system services, timezone and
11248 locale settings, user accounts---are declared in a single place. Such
11249 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
11251 One of the advantages of putting all the system configuration under the
11252 control of Guix is that it supports transactional system upgrades, and
11253 makes it possible to roll back to a previous system instantiation,
11254 should something go wrong with the new one (@pxref{Features}). Another
11255 advantage is that it makes it easy to replicate the exact same configuration
11256 across different machines, or at different points in time, without
11257 having to resort to additional administration tools layered on top of
11258 the own tools of the system.
11259 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
11261 This section describes this mechanism. First we focus on the system
11262 administrator's viewpoint---explaining how the system is configured and
11263 instantiated. Then we show how this mechanism can be extended, for
11264 instance to support new system services.
11267 * Using the Configuration System:: Customizing your GNU system.
11268 * operating-system Reference:: Detail of operating-system declarations.
11269 * File Systems:: Configuring file system mounts.
11270 * Mapped Devices:: Block device extra processing.
11271 * User Accounts:: Specifying user accounts.
11272 * Keyboard Layout:: How the system interprets key strokes.
11273 * Locales:: Language and cultural convention settings.
11274 * Services:: Specifying system services.
11275 * Setuid Programs:: Programs running with root privileges.
11276 * X.509 Certificates:: Authenticating HTTPS servers.
11277 * Name Service Switch:: Configuring libc's name service switch.
11278 * Initial RAM Disk:: Linux-Libre bootstrapping.
11279 * Bootloader Configuration:: Configuring the boot loader.
11280 * Invoking guix system:: Instantiating a system configuration.
11281 * Invoking guix deploy:: Deploying a system configuration to a remote host.
11282 * Running Guix in a VM:: How to run Guix System in a virtual machine.
11283 * Defining Services:: Adding new service definitions.
11286 @node Using the Configuration System
11287 @section Using the Configuration System
11289 The operating system is configured by providing an
11290 @code{operating-system} declaration in a file that can then be passed to
11291 the @command{guix system} command (@pxref{Invoking guix system}). A
11292 simple setup, with the default system services, the default Linux-Libre
11293 kernel, initial RAM disk, and boot loader looks like this:
11295 @findex operating-system
11297 @include os-config-bare-bones.texi
11300 This example should be self-describing. Some of the fields defined
11301 above, such as @code{host-name} and @code{bootloader}, are mandatory.
11302 Others, such as @code{packages} and @code{services}, can be omitted, in
11303 which case they get a default value.
11305 Below we discuss the effect of some of the most important fields
11306 (@pxref{operating-system Reference}, for details about all the available
11307 fields), and how to @dfn{instantiate} the operating system using
11308 @command{guix system}.
11310 @unnumberedsubsec Bootloader
11312 @cindex legacy boot, on Intel machines
11313 @cindex BIOS boot, on Intel machines
11316 The @code{bootloader} field describes the method that will be used to boot
11317 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
11318 mode, as in the example above. However, more recent machines rely instead on
11319 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
11320 the @code{bootloader} field should contain something along these lines:
11323 (bootloader-configuration
11324 (bootloader grub-efi-bootloader)
11325 (target "/boot/efi"))
11328 @xref{Bootloader Configuration}, for more information on the available
11329 configuration options.
11331 @unnumberedsubsec Globally-Visible Packages
11333 @vindex %base-packages
11334 The @code{packages} field lists packages that will be globally visible
11335 on the system, for all user accounts---i.e., in every user's @env{PATH}
11336 environment variable---in addition to the per-user profiles
11337 (@pxref{Invoking guix package}). The @code{%base-packages} variable
11338 provides all the tools one would expect for basic user and administrator
11339 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
11340 the GNU Zile lightweight text editor, @command{find}, @command{grep},
11341 etc. The example above adds GNU@tie{}Screen to those,
11342 taken from the @code{(gnu packages screen)}
11343 module (@pxref{Package Modules}). The
11344 @code{(list package output)} syntax can be used to add a specific output
11348 (use-modules (gnu packages))
11349 (use-modules (gnu packages dns))
11353 (packages (cons (list bind "utils")
11357 @findex specification->package
11358 Referring to packages by variable name, like @code{bind} above, has
11359 the advantage of being unambiguous; it also allows typos and such to be
11360 diagnosed right away as ``unbound variables''. The downside is that one
11361 needs to know which module defines which package, and to augment the
11362 @code{use-package-modules} line accordingly. To avoid that, one can use
11363 the @code{specification->package} procedure of the @code{(gnu packages)}
11364 module, which returns the best package for a given name or name and
11368 (use-modules (gnu packages))
11372 (packages (append (map specification->package
11373 '("tcpdump" "htop" "gnupg@@2.0"))
11377 @unnumberedsubsec System Services
11380 @vindex %base-services
11381 The @code{services} field lists @dfn{system services} to be made
11382 available when the system starts (@pxref{Services}).
11383 The @code{operating-system} declaration above specifies that, in
11384 addition to the basic services, we want the OpenSSH secure shell
11385 daemon listening on port 2222 (@pxref{Networking Services,
11386 @code{openssh-service-type}}). Under the hood,
11387 @code{openssh-service-type} arranges so that @command{sshd} is started with the
11388 right command-line options, possibly with supporting configuration files
11389 generated as needed (@pxref{Defining Services}).
11391 @cindex customization, of services
11392 @findex modify-services
11393 Occasionally, instead of using the base services as is, you will want to
11394 customize them. To do this, use @code{modify-services} (@pxref{Service
11395 Reference, @code{modify-services}}) to modify the list.
11397 For example, suppose you want to modify @code{guix-daemon} and Mingetty
11398 (the console log-in) in the @code{%base-services} list (@pxref{Base
11399 Services, @code{%base-services}}). To do that, you can write the
11400 following in your operating system declaration:
11403 (define %my-services
11404 ;; My very own list of services.
11405 (modify-services %base-services
11406 (guix-service-type config =>
11407 (guix-configuration
11409 (use-substitutes? #f)
11410 (extra-options '("--gc-keep-derivations"))))
11411 (mingetty-service-type config =>
11412 (mingetty-configuration
11413 (inherit config)))))
11417 (services %my-services))
11420 This changes the configuration---i.e., the service parameters---of the
11421 @code{guix-service-type} instance, and that of all the
11422 @code{mingetty-service-type} instances in the @code{%base-services} list.
11423 Observe how this is accomplished: first, we arrange for the original
11424 configuration to be bound to the identifier @code{config} in the
11425 @var{body}, and then we write the @var{body} so that it evaluates to the
11426 desired configuration. In particular, notice how we use @code{inherit}
11427 to create a new configuration which has the same values as the old
11428 configuration, but with a few modifications.
11430 @cindex encrypted disk
11431 The configuration for a typical ``desktop'' usage, with an encrypted
11432 root partition, the X11 display
11433 server, GNOME and Xfce (users can choose which of these desktop
11434 environments to use at the log-in screen by pressing @kbd{F1}), network
11435 management, power management, and more, would look like this:
11438 @include os-config-desktop.texi
11441 A graphical system with a choice of lightweight window managers
11442 instead of full-blown desktop environments would look like this:
11445 @include os-config-lightweight-desktop.texi
11448 This example refers to the @file{/boot/efi} file system by its UUID,
11449 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
11450 as returned by the @command{blkid} command.
11452 @xref{Desktop Services}, for the exact list of services provided by
11453 @code{%desktop-services}. @xref{X.509 Certificates}, for background
11454 information about the @code{nss-certs} package that is used here.
11456 Again, @code{%desktop-services} is just a list of service objects. If
11457 you want to remove services from there, you can do so using the
11458 procedures for list filtering (@pxref{SRFI-1 Filtering and
11459 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
11460 following expression returns a list that contains all the services in
11461 @code{%desktop-services} minus the Avahi service:
11464 (remove (lambda (service)
11465 (eq? (service-kind service) avahi-service-type))
11469 @unnumberedsubsec Instantiating the System
11471 Assuming the @code{operating-system} declaration
11472 is stored in the @file{my-system-config.scm}
11473 file, the @command{guix system reconfigure my-system-config.scm} command
11474 instantiates that configuration, and makes it the default GRUB boot
11475 entry (@pxref{Invoking guix system}).
11477 The normal way to change the system configuration is by updating this
11478 file and re-running @command{guix system reconfigure}. One should never
11479 have to touch files in @file{/etc} or to run commands that modify the
11480 system state such as @command{useradd} or @command{grub-install}. In
11481 fact, you must avoid that since that would not only void your warranty
11482 but also prevent you from rolling back to previous versions of your
11483 system, should you ever need to.
11485 @cindex roll-back, of the operating system
11486 Speaking of roll-back, each time you run @command{guix system
11487 reconfigure}, a new @dfn{generation} of the system is created---without
11488 modifying or deleting previous generations. Old system generations get
11489 an entry in the bootloader boot menu, allowing you to boot them in case
11490 something went wrong with the latest generation. Reassuring, no? The
11491 @command{guix system list-generations} command lists the system
11492 generations available on disk. It is also possible to roll back the
11493 system via the commands @command{guix system roll-back} and
11494 @command{guix system switch-generation}.
11496 Although the @command{guix system reconfigure} command will not modify
11497 previous generations, you must take care when the current generation is not
11498 the latest (e.g., after invoking @command{guix system roll-back}), since
11499 the operation might overwrite a later generation (@pxref{Invoking guix
11502 @unnumberedsubsec The Programming Interface
11504 At the Scheme level, the bulk of an @code{operating-system} declaration
11505 is instantiated with the following monadic procedure (@pxref{The Store
11508 @deffn {Monadic Procedure} operating-system-derivation os
11509 Return a derivation that builds @var{os}, an @code{operating-system}
11510 object (@pxref{Derivations}).
11512 The output of the derivation is a single directory that refers to all
11513 the packages, configuration files, and other supporting files needed to
11514 instantiate @var{os}.
11517 This procedure is provided by the @code{(gnu system)} module. Along
11518 with @code{(gnu services)} (@pxref{Services}), this module contains the
11519 guts of Guix System. Make sure to visit it!
11522 @node operating-system Reference
11523 @section @code{operating-system} Reference
11525 This section summarizes all the options available in
11526 @code{operating-system} declarations (@pxref{Using the Configuration
11529 @deftp {Data Type} operating-system
11530 This is the data type representing an operating system configuration.
11531 By that, we mean all the global system configuration, not per-user
11532 configuration (@pxref{Using the Configuration System}).
11535 @item @code{kernel} (default: @code{linux-libre})
11536 The package object of the operating system kernel to
11537 use@footnote{Currently only the Linux-libre kernel is fully supported.
11538 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
11539 available when building a virtual machine disk image.}.
11542 @item @code{hurd} (default: @code{#f})
11543 The package object of the hurd to be started by the kernel. When this
11544 field is set, produce a GNU/Hurd operating system. In that case,
11545 @code{kernel} must also be set to the @code{gnumach} package---the
11546 microkernel the Hurd runs on.
11549 This feature is experimental and only supported for disk images.
11552 @item @code{kernel-loadable-modules} (default: '())
11553 A list of objects (usually packages) to collect loadable kernel modules
11554 from--e.g. @code{(list ddcci-driver-linux)}.
11556 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
11557 List of strings or gexps representing additional arguments to pass on
11558 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
11560 @item @code{bootloader}
11561 The system bootloader configuration object. @xref{Bootloader Configuration}.
11564 This is the label (a string) as it appears in the bootloader's menu entry.
11565 The default label includes the kernel name and version.
11567 @item @code{keyboard-layout} (default: @code{#f})
11568 This field specifies the keyboard layout to use in the console. It can be
11569 either @code{#f}, in which case the default keyboard layout is used (usually
11570 US English), or a @code{<keyboard-layout>} record.
11572 This keyboard layout is in effect as soon as the kernel has booted. For
11573 instance, it is the keyboard layout in effect when you type a passphrase if
11574 your root file system is on a @code{luks-device-mapping} mapped device
11575 (@pxref{Mapped Devices}).
11578 This does @emph{not} specify the keyboard layout used by the bootloader, nor
11579 that used by the graphical display server. @xref{Bootloader Configuration},
11580 for information on how to specify the bootloader's keyboard layout. @xref{X
11581 Window}, for information on how to specify the keyboard layout used by the X
11585 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
11587 @cindex initial RAM disk
11588 The list of Linux kernel modules that need to be available in the
11589 initial RAM disk. @xref{Initial RAM Disk}.
11591 @item @code{initrd} (default: @code{base-initrd})
11592 A procedure that returns an initial RAM disk for the Linux
11593 kernel. This field is provided to support low-level customization and
11594 should rarely be needed for casual use. @xref{Initial RAM Disk}.
11596 @item @code{firmware} (default: @code{%base-firmware})
11598 List of firmware packages loadable by the operating system kernel.
11600 The default includes firmware needed for Atheros- and Broadcom-based
11601 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
11602 respectively). @xref{Hardware Considerations}, for more info on
11603 supported hardware.
11605 @item @code{host-name}
11608 @item @code{hosts-file}
11610 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
11611 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
11612 Reference Manual}). The default is a file with entries for
11613 @code{localhost} and @var{host-name}.
11615 @item @code{mapped-devices} (default: @code{'()})
11616 A list of mapped devices. @xref{Mapped Devices}.
11618 @item @code{file-systems}
11619 A list of file systems. @xref{File Systems}.
11621 @item @code{swap-devices} (default: @code{'()})
11622 @cindex swap devices
11623 A list of strings identifying devices or files to be used for ``swap
11624 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
11625 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
11626 It is possible to specify a swap file in a file system on a mapped
11627 device, provided that the necessary device mapping and file system are
11628 also specified. @xref{Mapped Devices} and @ref{File Systems}.
11630 @item @code{users} (default: @code{%base-user-accounts})
11631 @itemx @code{groups} (default: @code{%base-groups})
11632 List of user accounts and groups. @xref{User Accounts}.
11634 If the @code{users} list lacks a user account with UID@tie{}0, a
11635 ``root'' account with UID@tie{}0 is automatically added.
11637 @item @code{skeletons} (default: @code{(default-skeletons)})
11638 A list target file name/file-like object tuples (@pxref{G-Expressions,
11639 file-like objects}). These are the skeleton files that will be added to
11640 the home directory of newly-created user accounts.
11642 For instance, a valid value may look like this:
11645 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
11646 (".guile" ,(plain-file "guile"
11647 "(use-modules (ice-9 readline))
11648 (activate-readline)")))
11651 @item @code{issue} (default: @code{%default-issue})
11652 A string denoting the contents of the @file{/etc/issue} file, which is
11653 displayed when users log in on a text console.
11655 @item @code{packages} (default: @code{%base-packages})
11656 The set of packages installed in the global profile, which is accessible
11657 at @file{/run/current-system/profile}.
11659 The default set includes core utilities and it is good practice to
11660 install non-core utilities in user profiles (@pxref{Invoking guix
11663 @item @code{timezone}
11664 A timezone identifying string---e.g., @code{"Europe/Paris"}.
11666 You can run the @command{tzselect} command to find out which timezone
11667 string corresponds to your region. Choosing an invalid timezone name
11668 causes @command{guix system} to fail.
11670 @item @code{locale} (default: @code{"en_US.utf8"})
11671 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
11672 Library Reference Manual}). @xref{Locales}, for more information.
11674 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
11675 The list of locale definitions to be compiled and that may be used at
11676 run time. @xref{Locales}.
11678 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
11679 The list of GNU@tie{}libc packages whose locale data and tools are used
11680 to build the locale definitions. @xref{Locales}, for compatibility
11681 considerations that justify this option.
11683 @item @code{name-service-switch} (default: @code{%default-nss})
11684 Configuration of the libc name service switch (NSS)---a
11685 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
11688 @item @code{services} (default: @code{%base-services})
11689 A list of service objects denoting system services. @xref{Services}.
11691 @cindex essential services
11692 @item @code{essential-services} (default: ...)
11693 The list of ``essential services''---i.e., things like instances of
11694 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
11695 Reference}), which are derived from the operating system definition itself.
11696 As a user you should @emph{never} need to touch this field.
11698 @item @code{pam-services} (default: @code{(base-pam-services)})
11700 @cindex pluggable authentication modules
11701 Linux @dfn{pluggable authentication module} (PAM) services.
11702 @c FIXME: Add xref to PAM services section.
11704 @item @code{setuid-programs} (default: @code{%setuid-programs})
11705 List of string-valued G-expressions denoting setuid programs.
11706 @xref{Setuid Programs}.
11708 @item @code{sudoers-file} (default: @code{%sudoers-specification})
11709 @cindex sudoers file
11710 The contents of the @file{/etc/sudoers} file as a file-like object
11711 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
11713 This file specifies which users can use the @command{sudo} command, what
11714 they are allowed to do, and what privileges they may gain. The default
11715 is that only @code{root} and members of the @code{wheel} group may use
11720 @deffn {Scheme Syntax} this-operating-system
11721 When used in the @emph{lexical scope} of an operating system field definition,
11722 this identifier resolves to the operating system being defined.
11724 The example below shows how to refer to the operating system being defined in
11725 the definition of the @code{label} field:
11728 (use-modules (gnu) (guix))
11732 (label (package-full-name
11733 (operating-system-kernel this-operating-system))))
11736 It is an error to refer to @code{this-operating-system} outside an operating
11743 @section File Systems
11745 The list of file systems to be mounted is specified in the
11746 @code{file-systems} field of the operating system declaration
11747 (@pxref{Using the Configuration System}). Each file system is declared
11748 using the @code{file-system} form, like this:
11752 (mount-point "/home")
11753 (device "/dev/sda3")
11757 As usual, some of the fields are mandatory---those shown in the example
11758 above---while others can be omitted. These are described below.
11760 @deftp {Data Type} file-system
11761 Objects of this type represent file systems to be mounted. They
11762 contain the following members:
11766 This is a string specifying the type of the file system---e.g.,
11769 @item @code{mount-point}
11770 This designates the place where the file system is to be mounted.
11772 @item @code{device}
11773 This names the ``source'' of the file system. It can be one of three
11774 things: a file system label, a file system UUID, or the name of a
11775 @file{/dev} node. Labels and UUIDs offer a way to refer to file
11776 systems without having to hard-code their actual device
11777 name@footnote{Note that, while it is tempting to use
11778 @file{/dev/disk/by-uuid} and similar device names to achieve the same
11779 result, this is not recommended: These special device nodes are created
11780 by the udev daemon and may be unavailable at the time the device is
11783 @findex file-system-label
11784 File system labels are created using the @code{file-system-label}
11785 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
11786 plain strings. Here's an example of a file system referred to by its
11787 label, as shown by the @command{e2label} command:
11791 (mount-point "/home")
11793 (device (file-system-label "my-home")))
11797 UUIDs are converted from their string representation (as shown by the
11798 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
11799 @code{uuid} form expects 16-byte UUIDs as defined in
11800 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
11801 form of UUID used by the ext2 family of file systems and others, but it
11802 is different from ``UUIDs'' found in FAT file systems, for instance.},
11807 (mount-point "/home")
11809 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
11812 When the source of a file system is a mapped device (@pxref{Mapped
11813 Devices}), its @code{device} field @emph{must} refer to the mapped
11814 device name---e.g., @file{"/dev/mapper/root-partition"}.
11815 This is required so that
11816 the system knows that mounting the file system depends on having the
11817 corresponding device mapping established.
11819 @item @code{flags} (default: @code{'()})
11820 This is a list of symbols denoting mount flags. Recognized flags
11821 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
11822 access to special files), @code{no-suid} (ignore setuid and setgid
11823 bits), @code{no-atime} (do not update file access times),
11824 @code{strict-atime} (update file access time), @code{lazy-time} (only
11825 update time on the in-memory version of the file inode), and
11826 @code{no-exec} (disallow program execution).
11827 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
11828 Manual}, for more information on these flags.
11830 @item @code{options} (default: @code{#f})
11831 This is either @code{#f}, or a string denoting mount options passed to
11832 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
11833 Library Reference Manual}, for details and run @command{man 8 mount} for
11834 options for various file systems. Note that the
11835 @code{file-system-options->alist} and @code{alist->file-system-options}
11836 procedures from @code{(gnu system file-systems)} can be used to convert
11837 file system options given as an association list to the string
11838 representation, and vice-versa.
11840 @item @code{mount?} (default: @code{#t})
11841 This value indicates whether to automatically mount the file system when
11842 the system is brought up. When set to @code{#f}, the file system gets
11843 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
11844 is not automatically mounted.
11846 @item @code{needed-for-boot?} (default: @code{#f})
11847 This Boolean value indicates whether the file system is needed when
11848 booting. If that is true, then the file system is mounted when the
11849 initial RAM disk (initrd) is loaded. This is always the case, for
11850 instance, for the root file system.
11852 @item @code{check?} (default: @code{#t})
11853 This Boolean indicates whether the file system needs to be checked for
11854 errors before being mounted.
11856 @item @code{create-mount-point?} (default: @code{#f})
11857 When true, the mount point is created if it does not exist yet.
11859 @item @code{dependencies} (default: @code{'()})
11860 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
11861 representing file systems that must be mounted or mapped devices that
11862 must be opened before (and unmounted or closed after) this one.
11864 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
11865 a dependency of @file{/sys/fs/cgroup/cpu} and
11866 @file{/sys/fs/cgroup/memory}.
11868 Another example is a file system that depends on a mapped device, for
11869 example for an encrypted partition (@pxref{Mapped Devices}).
11873 The @code{(gnu system file-systems)} exports the following useful
11876 @defvr {Scheme Variable} %base-file-systems
11877 These are essential file systems that are required on normal systems,
11878 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
11879 below). Operating system declarations should always contain at least
11883 @defvr {Scheme Variable} %pseudo-terminal-file-system
11884 This is the file system to be mounted as @file{/dev/pts}. It supports
11885 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
11886 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
11887 Manual}). Pseudo-terminals are used by terminal emulators such as
11891 @defvr {Scheme Variable} %shared-memory-file-system
11892 This file system is mounted as @file{/dev/shm} and is used to support
11893 memory sharing across processes (@pxref{Memory-mapped I/O,
11894 @code{shm_open},, libc, The GNU C Library Reference Manual}).
11897 @defvr {Scheme Variable} %immutable-store
11898 This file system performs a read-only ``bind mount'' of
11899 @file{/gnu/store}, making it read-only for all the users including
11900 @code{root}. This prevents against accidental modification by software
11901 running as @code{root} or by system administrators.
11903 The daemon itself is still able to write to the store: it remounts it
11904 read-write in its own ``name space.''
11907 @defvr {Scheme Variable} %binary-format-file-system
11908 The @code{binfmt_misc} file system, which allows handling of arbitrary
11909 executable file types to be delegated to user space. This requires the
11910 @code{binfmt.ko} kernel module to be loaded.
11913 @defvr {Scheme Variable} %fuse-control-file-system
11914 The @code{fusectl} file system, which allows unprivileged users to mount
11915 and unmount user-space FUSE file systems. This requires the
11916 @code{fuse.ko} kernel module to be loaded.
11919 @node Btrfs file system
11920 @subsection Btrfs file system
11922 The Btrfs has special features, such as subvolumes, that merit being
11923 explained in more details. The following section attempts to cover
11924 basic as well as complex uses of a Btrfs file system with the Guix
11927 In its simplest usage, a Btrfs file system can be described, for
11932 (mount-point "/home")
11934 (device (file-system-label "my-home")))
11937 The example below is more complex, as it makes use of a Btrfs
11938 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
11939 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
11940 dependency on @code{mapped-devices}):
11944 (device (file-system-label "my-btrfs-pool"))
11947 (options "subvol=rootfs")
11948 (dependencies mapped-devices))
11951 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
11952 top level during the early boot, and rely on their configuration to
11953 refer to the correct subvolume path within that top level. The
11954 bootloaders operating in this way typically produce their configuration
11955 on a running system where the Btrfs partitions are already mounted and
11956 where the subvolume information is readily available. As an example,
11957 @command{grub-mkconfig}, the configuration generator command shipped
11958 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
11959 path of a subvolume.
11961 The Guix System produces a bootloader configuration using the operating
11962 system configuration as its sole input; it is therefore necessary to
11963 extract the subvolume name on which @file{/gnu/store} lives (if any)
11964 from that operating system configuration. To better illustrate,
11965 consider a subvolume named 'rootfs' which contains the root file system
11966 data. In such situation, the GRUB bootloader would only see the top
11967 level of the root Btrfs partition, e.g.:
11971 ├── rootfs (subvolume directory)
11972 ├── gnu (normal directory)
11973 ├── store (normal directory)
11977 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
11978 of the kernel, initrd binaries and any other files referred to in the
11979 GRUB configuration that must be found during the early boot.
11981 The next example shows a nested hierarchy of subvolumes and
11986 ├── rootfs (subvolume)
11987 ├── gnu (normal directory)
11988 ├── store (subvolume)
11992 This scenario would work without mounting the 'store' subvolume.
11993 Mounting 'rootfs' is sufficient, since the subvolume name matches its
11994 intended mount point in the file system hierarchy. Alternatively, the
11995 'store' subvolume could be referred to by setting the @code{subvol}
11996 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
11998 Finally, a more contrived example of nested subvolumes:
12002 ├── root-snapshots (subvolume)
12003 ├── root-current (subvolume)
12004 ├── guix-store (subvolume)
12008 Here, the 'guix-store' subvolume doesn't match its intended mount point,
12009 so it is necessary to mount it. The subvolume must be fully specified,
12010 by passing its file name to the @code{subvol} option. To illustrate,
12011 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
12012 a file system declaration such as:
12016 (device (file-system-label "btrfs-pool-1"))
12017 (mount-point "/gnu/store")
12019 (options "subvol=root-snapshots/root-current/guix-store,\
12020 compress-force=zstd,space_cache=v2"))
12023 @node Mapped Devices
12024 @section Mapped Devices
12026 @cindex device mapping
12027 @cindex mapped devices
12028 The Linux kernel has a notion of @dfn{device mapping}: a block device,
12029 such as a hard disk partition, can be @dfn{mapped} into another device,
12030 usually in @code{/dev/mapper/},
12031 with additional processing over the data that flows through
12032 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
12033 concept of a ``mapped device'' and that of a file system: both boil down
12034 to @emph{translating} input/output operations made on a file to
12035 operations on its backing store. Thus, the Hurd implements mapped
12036 devices, like file systems, using the generic @dfn{translator} mechanism
12037 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
12038 typical example is encryption device mapping: all writes to the mapped
12039 device are encrypted, and all reads are deciphered, transparently.
12040 Guix extends this notion by considering any device or set of devices that
12041 are @dfn{transformed} in some way to create a new device; for instance,
12042 RAID devices are obtained by @dfn{assembling} several other devices, such
12043 as hard disks or partitions, into a new one that behaves as one partition.
12044 Other examples, not yet implemented, are LVM logical volumes.
12046 Mapped devices are declared using the @code{mapped-device} form,
12047 defined as follows; for examples, see below.
12049 @deftp {Data Type} mapped-device
12050 Objects of this type represent device mappings that will be made when
12051 the system boots up.
12055 This is either a string specifying the name of the block device to be mapped,
12056 such as @code{"/dev/sda3"}, or a list of such strings when several devices
12057 need to be assembled for creating a new one.
12060 This string specifies the name of the resulting mapped device. For
12061 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
12062 specifying @code{"my-partition"} leads to the creation of
12063 the @code{"/dev/mapper/my-partition"} device.
12064 For RAID devices of type @code{raid-device-mapping}, the full device name
12065 such as @code{"/dev/md0"} needs to be given.
12068 This must be a @code{mapped-device-kind} object, which specifies how
12069 @var{source} is mapped to @var{target}.
12073 @defvr {Scheme Variable} luks-device-mapping
12074 This defines LUKS block device encryption using the @command{cryptsetup}
12075 command from the package with the same name. It relies on the
12076 @code{dm-crypt} Linux kernel module.
12079 @defvr {Scheme Variable} raid-device-mapping
12080 This defines a RAID device, which is assembled using the @code{mdadm}
12081 command from the package with the same name. It requires a Linux kernel
12082 module for the appropriate RAID level to be loaded, such as @code{raid456}
12083 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
12086 @cindex disk encryption
12088 The following example specifies a mapping from @file{/dev/sda3} to
12089 @file{/dev/mapper/home} using LUKS---the
12090 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
12091 standard mechanism for disk encryption.
12092 The @file{/dev/mapper/home}
12093 device can then be used as the @code{device} of a @code{file-system}
12094 declaration (@pxref{File Systems}).
12098 (source "/dev/sda3")
12100 (type luks-device-mapping))
12103 Alternatively, to become independent of device numbering, one may obtain
12104 the LUKS UUID (@dfn{unique identifier}) of the source device by a
12108 cryptsetup luksUUID /dev/sda3
12111 and use it as follows:
12115 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
12117 (type luks-device-mapping))
12120 @cindex swap encryption
12121 It is also desirable to encrypt swap space, since swap space may contain
12122 sensitive data. One way to accomplish that is to use a swap file in a
12123 file system on a device mapped via LUKS encryption. In this way, the
12124 swap file is encrypted because the entire device is encrypted.
12125 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
12127 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
12128 may be declared as follows:
12132 (source (list "/dev/sda1" "/dev/sdb1"))
12133 (target "/dev/md0")
12134 (type raid-device-mapping))
12137 The @file{/dev/md0} device can then be used as the @code{device} of a
12138 @code{file-system} declaration (@pxref{File Systems}).
12139 Note that the RAID level need not be given; it is chosen during the
12140 initial creation and formatting of the RAID device and is determined
12141 automatically later.
12144 @node User Accounts
12145 @section User Accounts
12149 @cindex user accounts
12150 User accounts and groups are entirely managed through the
12151 @code{operating-system} declaration. They are specified with the
12152 @code{user-account} and @code{user-group} forms:
12158 (supplementary-groups '("wheel" ;allow use of sudo, etc.
12159 "audio" ;sound card
12160 "video" ;video devices such as webcams
12161 "cdrom")) ;the good ol' CD-ROM
12162 (comment "Bob's sister")
12163 (home-directory "/home/alice"))
12166 When booting or upon completion of @command{guix system reconfigure},
12167 the system ensures that only the user accounts and groups specified in
12168 the @code{operating-system} declaration exist, and with the specified
12169 properties. Thus, account or group creations or modifications made by
12170 directly invoking commands such as @command{useradd} are lost upon
12171 reconfiguration or reboot. This ensures that the system remains exactly
12174 @deftp {Data Type} user-account
12175 Objects of this type represent user accounts. The following members may
12180 The name of the user account.
12184 This is the name (a string) or identifier (a number) of the user group
12185 this account belongs to.
12187 @item @code{supplementary-groups} (default: @code{'()})
12188 Optionally, this can be defined as a list of group names that this
12189 account belongs to.
12191 @item @code{uid} (default: @code{#f})
12192 This is the user ID for this account (a number), or @code{#f}. In the
12193 latter case, a number is automatically chosen by the system when the
12194 account is created.
12196 @item @code{comment} (default: @code{""})
12197 A comment about the account, such as the account owner's full name.
12199 @item @code{home-directory}
12200 This is the name of the home directory for the account.
12202 @item @code{create-home-directory?} (default: @code{#t})
12203 Indicates whether the home directory of this account should be created
12204 if it does not exist yet.
12206 @item @code{shell} (default: Bash)
12207 This is a G-expression denoting the file name of a program to be used as
12208 the shell (@pxref{G-Expressions}).
12210 @item @code{system?} (default: @code{#f})
12211 This Boolean value indicates whether the account is a ``system''
12212 account. System accounts are sometimes treated specially; for instance,
12213 graphical login managers do not list them.
12215 @anchor{user-account-password}
12216 @cindex password, for user accounts
12217 @item @code{password} (default: @code{#f})
12218 You would normally leave this field to @code{#f}, initialize user
12219 passwords as @code{root} with the @command{passwd} command, and then let
12220 users change it with @command{passwd}. Passwords set with
12221 @command{passwd} are of course preserved across reboot and
12224 If you @emph{do} want to set an initial password for an account, then
12225 this field must contain the encrypted password, as a string. You can use the
12226 @code{crypt} procedure for this purpose:
12233 ;; Specify a SHA-512-hashed initial password.
12234 (password (crypt "InitialPassword!" "$6$abc")))
12238 The hash of this initial password will be available in a file in
12239 @file{/gnu/store}, readable by all the users, so this method must be used with
12243 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
12244 more information on password encryption, and @ref{Encryption,,, guile, GNU
12245 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
12251 User group declarations are even simpler:
12254 (user-group (name "students"))
12257 @deftp {Data Type} user-group
12258 This type is for, well, user groups. There are just a few fields:
12262 The name of the group.
12264 @item @code{id} (default: @code{#f})
12265 The group identifier (a number). If @code{#f}, a new number is
12266 automatically allocated when the group is created.
12268 @item @code{system?} (default: @code{#f})
12269 This Boolean value indicates whether the group is a ``system'' group.
12270 System groups have low numerical IDs.
12272 @item @code{password} (default: @code{#f})
12273 What, user groups can have a password? Well, apparently yes. Unless
12274 @code{#f}, this field specifies the password of the group.
12279 For convenience, a variable lists all the basic user groups one may
12282 @defvr {Scheme Variable} %base-groups
12283 This is the list of basic user groups that users and/or packages expect
12284 to be present on the system. This includes groups such as ``root'',
12285 ``wheel'', and ``users'', as well as groups used to control access to
12286 specific devices such as ``audio'', ``disk'', and ``cdrom''.
12289 @defvr {Scheme Variable} %base-user-accounts
12290 This is the list of basic system accounts that programs may expect to
12291 find on a GNU/Linux system, such as the ``nobody'' account.
12293 Note that the ``root'' account is not included here. It is a
12294 special-case and is automatically added whether or not it is specified.
12297 @node Keyboard Layout
12298 @section Keyboard Layout
12300 @cindex keyboard layout
12302 To specify what each key of your keyboard does, you need to tell the operating
12303 system what @dfn{keyboard layout} you want to use. The default, when nothing
12304 is specified, is the US English QWERTY layout for 105-key PC keyboards.
12305 However, German speakers will usually prefer the German QWERTZ layout, French
12306 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
12307 or bépo, and they might even want to further customize the effect of some of
12308 the keys. This section explains how to get that done.
12310 @cindex keyboard layout, definition
12311 There are three components that will want to know about your keyboard layout:
12315 The @emph{bootloader} may want to know what keyboard layout you want to use
12316 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
12317 you want, for instance, to make sure that you can type the passphrase of your
12318 encrypted root partition using the right layout.
12321 The @emph{operating system kernel}, Linux, will need that so that the console
12322 is properly configured (@pxref{operating-system Reference,
12323 @code{keyboard-layout}}).
12326 The @emph{graphical display server}, usually Xorg, also has its own idea of
12327 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
12330 Guix allows you to configure all three separately but, fortunately, it allows
12331 you to share the same keyboard layout for all three components.
12333 @cindex XKB, keyboard layouts
12334 Keyboard layouts are represented by records created by the
12335 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
12336 the X Keyboard extension (XKB), each layout has four attributes: a name (often
12337 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
12338 optional variant name, an optional keyboard model name, and a possibly empty
12339 list of additional options. In most cases the layout name is all you care
12340 about. Here are a few example:
12343 ;; The German QWERTZ layout. Here we assume a standard
12344 ;; "pc105" keyboard model.
12345 (keyboard-layout "de")
12347 ;; The bépo variant of the French layout.
12348 (keyboard-layout "fr" "bepo")
12350 ;; The Catalan layout.
12351 (keyboard-layout "es" "cat")
12353 ;; Arabic layout with "Alt-Shift" to switch to US layout.
12354 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
12356 ;; The Latin American Spanish layout. In addition, the
12357 ;; "Caps Lock" key is used as an additional "Ctrl" key,
12358 ;; and the "Menu" key is used as a "Compose" key to enter
12359 ;; accented letters.
12360 (keyboard-layout "latam"
12361 #:options '("ctrl:nocaps" "compose:menu"))
12363 ;; The Russian layout for a ThinkPad keyboard.
12364 (keyboard-layout "ru" #:model "thinkpad")
12366 ;; The "US international" layout, which is the US layout plus
12367 ;; dead keys to enter accented characters. This is for an
12368 ;; Apple MacBook keyboard.
12369 (keyboard-layout "us" "intl" #:model "macbook78")
12372 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
12373 for a complete list of supported layouts, variants, and models.
12375 @cindex keyboard layout, configuration
12376 Let's say you want your system to use the Turkish keyboard layout throughout
12377 your system---bootloader, console, and Xorg. Here's what your system
12378 configuration would look like:
12380 @findex set-xorg-configuration
12382 ;; Using the Turkish layout for the bootloader, the console,
12387 (keyboard-layout (keyboard-layout "tr")) ;for the console
12388 (bootloader (bootloader-configuration
12389 (bootloader grub-efi-bootloader)
12390 (target "/boot/efi")
12391 (keyboard-layout keyboard-layout))) ;for GRUB
12392 (services (cons (set-xorg-configuration
12393 (xorg-configuration ;for Xorg
12394 (keyboard-layout keyboard-layout)))
12395 %desktop-services)))
12398 In the example above, for GRUB and for Xorg, we just refer to the
12399 @code{keyboard-layout} field defined above, but we could just as well refer to
12400 a different layout. The @code{set-xorg-configuration} procedure communicates
12401 the desired Xorg configuration to the graphical log-in manager, by default
12404 We've discussed how to specify the @emph{default} keyboard layout of your
12405 system when it starts, but you can also adjust it at run time:
12409 If you're using GNOME, its settings panel has a ``Region & Language'' entry
12410 where you can select one or more keyboard layouts.
12413 Under Xorg, the @command{setxkbmap} command (from the same-named package)
12414 allows you to change the current layout. For example, this is how you would
12415 change the layout to US Dvorak:
12418 setxkbmap us dvorak
12422 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
12423 console. However, note that @code{loadkeys} does @emph{not} use the XKB
12424 keyboard layout categorization described above. The command below loads the
12425 French bépo layout:
12436 A @dfn{locale} defines cultural conventions for a particular language
12437 and region of the world (@pxref{Locales,,, libc, The GNU C Library
12438 Reference Manual}). Each locale has a name that typically has the form
12439 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
12440 @code{fr_LU.utf8} designates the locale for the French language, with
12441 cultural conventions from Luxembourg, and using the UTF-8 encoding.
12443 @cindex locale definition
12444 Usually, you will want to specify the default locale for the machine
12445 using the @code{locale} field of the @code{operating-system} declaration
12446 (@pxref{operating-system Reference, @code{locale}}).
12448 The selected locale is automatically added to the @dfn{locale
12449 definitions} known to the system if needed, with its codeset inferred
12450 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
12451 @code{UTF-8} codeset. Additional locale definitions can be specified in
12452 the @code{locale-definitions} slot of @code{operating-system}---this is
12453 useful, for instance, if the codeset could not be inferred from the
12454 locale name. The default set of locale definitions includes some widely
12455 used locales, but not all the available locales, in order to save space.
12457 For instance, to add the North Frisian locale for Germany, the value of
12461 (cons (locale-definition
12462 (name "fy_DE.utf8") (source "fy_DE"))
12463 %default-locale-definitions)
12466 Likewise, to save space, one might want @code{locale-definitions} to
12467 list only the locales that are actually used, as in:
12470 (list (locale-definition
12471 (name "ja_JP.eucjp") (source "ja_JP")
12472 (charset "EUC-JP")))
12476 The compiled locale definitions are available at
12477 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
12478 version, which is the default location where the GNU@tie{}libc provided
12479 by Guix looks for locale data. This can be overridden using the
12480 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
12481 @env{LOCPATH} and locale packages}).
12483 The @code{locale-definition} form is provided by the @code{(gnu system
12484 locale)} module. Details are given below.
12486 @deftp {Data Type} locale-definition
12487 This is the data type of a locale definition.
12492 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
12493 Reference Manual}, for more information on locale names.
12495 @item @code{source}
12496 The name of the source for that locale. This is typically the
12497 @code{@var{language}_@var{territory}} part of the locale name.
12499 @item @code{charset} (default: @code{"UTF-8"})
12500 The ``character set'' or ``code set'' for that locale,
12501 @uref{https://www.iana.org/assignments/character-sets, as defined by
12507 @defvr {Scheme Variable} %default-locale-definitions
12508 A list of commonly used UTF-8 locales, used as the default
12509 value of the @code{locale-definitions} field of @code{operating-system}
12512 @cindex locale name
12513 @cindex normalized codeset in locale names
12514 These locale definitions use the @dfn{normalized codeset} for the part
12515 that follows the dot in the name (@pxref{Using gettextized software,
12516 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
12517 instance it has @code{uk_UA.utf8} but @emph{not}, say,
12518 @code{uk_UA.UTF-8}.
12521 @subsection Locale Data Compatibility Considerations
12523 @cindex incompatibility, of locale data
12524 @code{operating-system} declarations provide a @code{locale-libcs} field
12525 to specify the GNU@tie{}libc packages that are used to compile locale
12526 declarations (@pxref{operating-system Reference}). ``Why would I
12527 care?'', you may ask. Well, it turns out that the binary format of
12528 locale data is occasionally incompatible from one libc version to
12531 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
12532 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
12533 For instance, a program linked against libc version 2.21 is unable to
12534 read locale data produced with libc 2.22; worse, that program
12535 @emph{aborts} instead of simply ignoring the incompatible locale
12536 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
12537 the incompatible locale data, which is already an improvement.}.
12538 Similarly, a program linked against libc 2.22 can read most, but not
12539 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
12540 data is incompatible); thus calls to @code{setlocale} may fail, but
12541 programs will not abort.
12543 The ``problem'' with Guix is that users have a lot of freedom: They can
12544 choose whether and when to upgrade software in their profiles, and might
12545 be using a libc version different from the one the system administrator
12546 used to build the system-wide locale data.
12548 Fortunately, unprivileged users can also install their own locale data
12549 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
12550 @env{GUIX_LOCPATH} and locale packages}).
12552 Still, it is best if the system-wide locale data at
12553 @file{/run/current-system/locale} is built for all the libc versions
12554 actually in use on the system, so that all the programs can access
12555 it---this is especially crucial on a multi-user system. To do that, the
12556 administrator can specify several libc packages in the
12557 @code{locale-libcs} field of @code{operating-system}:
12560 (use-package-modules base)
12564 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
12567 This example would lead to a system containing locale definitions for
12568 both libc 2.21 and the current version of libc in
12569 @file{/run/current-system/locale}.
12575 @cindex system services
12576 An important part of preparing an @code{operating-system} declaration is
12577 listing @dfn{system services} and their configuration (@pxref{Using the
12578 Configuration System}). System services are typically daemons launched
12579 when the system boots, or other actions needed at that time---e.g.,
12580 configuring network access.
12582 Guix has a broad definition of ``service'' (@pxref{Service
12583 Composition}), but many services are managed by the GNU@tie{}Shepherd
12584 (@pxref{Shepherd Services}). On a running system, the @command{herd}
12585 command allows you to list the available services, show their status,
12586 start and stop them, or do other specific operations (@pxref{Jump
12587 Start,,, shepherd, The GNU Shepherd Manual}). For example:
12593 The above command, run as @code{root}, lists the currently defined
12594 services. The @command{herd doc} command shows a synopsis of the given
12595 service and its associated actions:
12599 Run libc's name service cache daemon (nscd).
12601 # herd doc nscd action invalidate
12602 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
12605 The @command{start}, @command{stop}, and @command{restart} sub-commands
12606 have the effect you would expect. For instance, the commands below stop
12607 the nscd service and restart the Xorg display server:
12611 Service nscd has been stopped.
12612 # herd restart xorg-server
12613 Service xorg-server has been stopped.
12614 Service xorg-server has been started.
12617 The following sections document the available services, starting with
12618 the core services, that may be used in an @code{operating-system}
12622 * Base Services:: Essential system services.
12623 * Scheduled Job Execution:: The mcron service.
12624 * Log Rotation:: The rottlog service.
12625 * Networking Services:: Network setup, SSH daemon, etc.
12626 * X Window:: Graphical display.
12627 * Printing Services:: Local and remote printer support.
12628 * Desktop Services:: D-Bus and desktop services.
12629 * Sound Services:: ALSA and Pulseaudio services.
12630 * Database Services:: SQL databases, key-value stores, etc.
12631 * Mail Services:: IMAP, POP3, SMTP, and all that.
12632 * Messaging Services:: Messaging services.
12633 * Telephony Services:: Telephony services.
12634 * Monitoring Services:: Monitoring services.
12635 * Kerberos Services:: Kerberos services.
12636 * LDAP Services:: LDAP services.
12637 * Web Services:: Web servers.
12638 * Certificate Services:: TLS certificates via Let's Encrypt.
12639 * DNS Services:: DNS daemons.
12640 * VPN Services:: VPN daemons.
12641 * Network File System:: NFS related services.
12642 * Continuous Integration:: The Cuirass service.
12643 * Power Management Services:: Extending battery life.
12644 * Audio Services:: The MPD.
12645 * Virtualization Services:: Virtualization services.
12646 * Version Control Services:: Providing remote access to Git repositories.
12647 * Game Services:: Game servers.
12648 * PAM Mount Service:: Service to mount volumes when logging in.
12649 * Guix Services:: Services relating specifically to Guix.
12650 * Linux Services:: Services tied to the Linux kernel.
12651 * Hurd Services:: Services specific for a Hurd System.
12652 * Miscellaneous Services:: Other services.
12655 @node Base Services
12656 @subsection Base Services
12658 The @code{(gnu services base)} module provides definitions for the basic
12659 services that one expects from the system. The services exported by
12660 this module are listed below.
12662 @defvr {Scheme Variable} %base-services
12663 This variable contains a list of basic services (@pxref{Service Types
12664 and Services}, for more information on service objects) one would
12665 expect from the system: a login service (mingetty) on each tty, syslogd,
12666 the libc name service cache daemon (nscd), the udev device manager, and
12669 This is the default value of the @code{services} field of
12670 @code{operating-system} declarations. Usually, when customizing a
12671 system, you will want to append services to @code{%base-services}, like
12675 (append (list (service avahi-service-type)
12676 (service openssh-service-type))
12681 @defvr {Scheme Variable} special-files-service-type
12682 This is the service that sets up ``special files'' such as
12683 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
12685 The value associated with @code{special-files-service-type} services
12686 must be a list of tuples where the first element is the ``special file''
12687 and the second element is its target. By default it is:
12689 @cindex @file{/bin/sh}
12690 @cindex @file{sh}, in @file{/bin}
12692 `(("/bin/sh" ,(file-append bash "/bin/sh")))
12695 @cindex @file{/usr/bin/env}
12696 @cindex @file{env}, in @file{/usr/bin}
12697 If you want to add, say, @code{/usr/bin/env} to your system, you can
12701 `(("/bin/sh" ,(file-append bash "/bin/sh"))
12702 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
12705 Since this is part of @code{%base-services}, you can use
12706 @code{modify-services} to customize the set of special files
12707 (@pxref{Service Reference, @code{modify-services}}). But the simple way
12708 to add a special file is @i{via} the @code{extra-special-file} procedure
12712 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
12713 Use @var{target} as the ``special file'' @var{file}.
12715 For example, adding the following lines to the @code{services} field of
12716 your operating system declaration leads to a @file{/usr/bin/env}
12720 (extra-special-file "/usr/bin/env"
12721 (file-append coreutils "/bin/env"))
12725 @deffn {Scheme Procedure} host-name-service @var{name}
12726 Return a service that sets the host name to @var{name}.
12729 @defvr {Scheme Variable} console-font-service-type
12730 Install the given fonts on the specified ttys (fonts are per
12731 virtual console on the kernel Linux). The value of this service is a list of
12732 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
12733 package or any valid argument to @command{setfont}, as in this example:
12736 `(("tty1" . "LatGrkCyr-8x16")
12737 ("tty2" . ,(file-append
12739 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
12740 ("tty3" . ,(file-append
12742 "/share/consolefonts/ter-132n"))) ; for HDPI
12746 @deffn {Scheme Procedure} login-service @var{config}
12747 Return a service to run login according to @var{config}, a
12748 @code{<login-configuration>} object, which specifies the message of the day,
12749 among other things.
12752 @deftp {Data Type} login-configuration
12753 This is the data type representing the configuration of login.
12758 @cindex message of the day
12759 A file-like object containing the ``message of the day''.
12761 @item @code{allow-empty-passwords?} (default: @code{#t})
12762 Allow empty passwords by default so that first-time users can log in when
12763 the 'root' account has just been created.
12768 @deffn {Scheme Procedure} mingetty-service @var{config}
12769 Return a service to run mingetty according to @var{config}, a
12770 @code{<mingetty-configuration>} object, which specifies the tty to run, among
12774 @deftp {Data Type} mingetty-configuration
12775 This is the data type representing the configuration of Mingetty, which
12776 provides the default implementation of virtual console log-in.
12781 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
12783 @item @code{auto-login} (default: @code{#f})
12784 When true, this field must be a string denoting the user name under
12785 which the system automatically logs in. When it is @code{#f}, a
12786 user name and password must be entered to log in.
12788 @item @code{login-program} (default: @code{#f})
12789 This must be either @code{#f}, in which case the default log-in program
12790 is used (@command{login} from the Shadow tool suite), or a gexp denoting
12791 the name of the log-in program.
12793 @item @code{login-pause?} (default: @code{#f})
12794 When set to @code{#t} in conjunction with @var{auto-login}, the user
12795 will have to press a key before the log-in shell is launched.
12797 @item @code{mingetty} (default: @var{mingetty})
12798 The Mingetty package to use.
12803 @deffn {Scheme Procedure} agetty-service @var{config}
12804 Return a service to run agetty according to @var{config}, an
12805 @code{<agetty-configuration>} object, which specifies the tty to run,
12806 among other things.
12809 @deftp {Data Type} agetty-configuration
12810 This is the data type representing the configuration of agetty, which
12811 implements virtual and serial console log-in. See the @code{agetty(8)}
12812 man page for more information.
12817 The name of the console this agetty runs on, as a string---e.g.,
12818 @code{"ttyS0"}. This argument is optional, it will default to
12819 a reasonable default serial port used by the kernel Linux.
12821 For this, if there is a value for an option @code{agetty.tty} in the kernel
12822 command line, agetty will extract the device name of the serial port
12823 from it and use that.
12825 If not and if there is a value for an option @code{console} with a tty in
12826 the Linux command line, agetty will extract the device name of the
12827 serial port from it and use that.
12829 In both cases, agetty will leave the other serial device settings
12830 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
12833 @item @code{baud-rate} (default: @code{#f})
12834 A string containing a comma-separated list of one or more baud rates, in
12837 @item @code{term} (default: @code{#f})
12838 A string containing the value used for the @env{TERM} environment
12841 @item @code{eight-bits?} (default: @code{#f})
12842 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
12845 @item @code{auto-login} (default: @code{#f})
12846 When passed a login name, as a string, the specified user will be logged
12847 in automatically without prompting for their login name or password.
12849 @item @code{no-reset?} (default: @code{#f})
12850 When @code{#t}, don't reset terminal cflags (control modes).
12852 @item @code{host} (default: @code{#f})
12853 This accepts a string containing the ``login_host'', which will be written
12854 into the @file{/var/run/utmpx} file.
12856 @item @code{remote?} (default: @code{#f})
12857 When set to @code{#t} in conjunction with @var{host}, this will add an
12858 @code{-r} fakehost option to the command line of the login program
12859 specified in @var{login-program}.
12861 @item @code{flow-control?} (default: @code{#f})
12862 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
12864 @item @code{no-issue?} (default: @code{#f})
12865 When set to @code{#t}, the contents of the @file{/etc/issue} file will
12866 not be displayed before presenting the login prompt.
12868 @item @code{init-string} (default: @code{#f})
12869 This accepts a string that will be sent to the tty or modem before
12870 sending anything else. It can be used to initialize a modem.
12872 @item @code{no-clear?} (default: @code{#f})
12873 When set to @code{#t}, agetty will not clear the screen before showing
12876 @item @code{login-program} (default: (file-append shadow "/bin/login"))
12877 This must be either a gexp denoting the name of a log-in program, or
12878 unset, in which case the default value is the @command{login} from the
12881 @item @code{local-line} (default: @code{#f})
12882 Control the CLOCAL line flag. This accepts one of three symbols as
12883 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
12884 the default value chosen by agetty is @code{'auto}.
12886 @item @code{extract-baud?} (default: @code{#f})
12887 When set to @code{#t}, instruct agetty to try to extract the baud rate
12888 from the status messages produced by certain types of modems.
12890 @item @code{skip-login?} (default: @code{#f})
12891 When set to @code{#t}, do not prompt the user for a login name. This
12892 can be used with @var{login-program} field to use non-standard login
12895 @item @code{no-newline?} (default: @code{#f})
12896 When set to @code{#t}, do not print a newline before printing the
12897 @file{/etc/issue} file.
12899 @c Is this dangerous only when used with login-program, or always?
12900 @item @code{login-options} (default: @code{#f})
12901 This option accepts a string containing options that are passed to the
12902 login program. When used with the @var{login-program}, be aware that a
12903 malicious user could try to enter a login name containing embedded
12904 options that could be parsed by the login program.
12906 @item @code{login-pause} (default: @code{#f})
12907 When set to @code{#t}, wait for any key before showing the login prompt.
12908 This can be used in conjunction with @var{auto-login} to save memory by
12909 lazily spawning shells.
12911 @item @code{chroot} (default: @code{#f})
12912 Change root to the specified directory. This option accepts a directory
12915 @item @code{hangup?} (default: @code{#f})
12916 Use the Linux system call @code{vhangup} to do a virtual hangup of the
12917 specified terminal.
12919 @item @code{keep-baud?} (default: @code{#f})
12920 When set to @code{#t}, try to keep the existing baud rate. The baud
12921 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
12924 @item @code{timeout} (default: @code{#f})
12925 When set to an integer value, terminate if no user name could be read
12926 within @var{timeout} seconds.
12928 @item @code{detect-case?} (default: @code{#f})
12929 When set to @code{#t}, turn on support for detecting an uppercase-only
12930 terminal. This setting will detect a login name containing only
12931 uppercase letters as indicating an uppercase-only terminal and turn on
12932 some upper-to-lower case conversions. Note that this will not support
12933 Unicode characters.
12935 @item @code{wait-cr?} (default: @code{#f})
12936 When set to @code{#t}, wait for the user or modem to send a
12937 carriage-return or linefeed character before displaying
12938 @file{/etc/issue} or login prompt. This is typically used with the
12939 @var{init-string} option.
12941 @item @code{no-hints?} (default: @code{#f})
12942 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
12945 @item @code{no-hostname?} (default: @code{#f})
12946 By default, the hostname is printed. When this option is set to
12947 @code{#t}, no hostname will be shown at all.
12949 @item @code{long-hostname?} (default: @code{#f})
12950 By default, the hostname is only printed until the first dot. When this
12951 option is set to @code{#t}, the fully qualified hostname by
12952 @code{gethostname} or @code{getaddrinfo} is shown.
12954 @item @code{erase-characters} (default: @code{#f})
12955 This option accepts a string of additional characters that should be
12956 interpreted as backspace when the user types their login name.
12958 @item @code{kill-characters} (default: @code{#f})
12959 This option accepts a string that should be interpreted to mean ``ignore
12960 all previous characters'' (also called a ``kill'' character) when the user
12961 types their login name.
12963 @item @code{chdir} (default: @code{#f})
12964 This option accepts, as a string, a directory path that will be changed
12967 @item @code{delay} (default: @code{#f})
12968 This options accepts, as an integer, the number of seconds to sleep
12969 before opening the tty and displaying the login prompt.
12971 @item @code{nice} (default: @code{#f})
12972 This option accepts, as an integer, the nice value with which to run the
12973 @command{login} program.
12975 @item @code{extra-options} (default: @code{'()})
12976 This option provides an ``escape hatch'' for the user to provide arbitrary
12977 command-line arguments to @command{agetty} as a list of strings.
12982 @deffn {Scheme Procedure} kmscon-service-type @var{config}
12983 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
12984 according to @var{config}, a @code{<kmscon-configuration>} object, which
12985 specifies the tty to run, among other things.
12988 @deftp {Data Type} kmscon-configuration
12989 This is the data type representing the configuration of Kmscon, which
12990 implements virtual console log-in.
12994 @item @code{virtual-terminal}
12995 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
12997 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
12998 A gexp denoting the name of the log-in program. The default log-in program is
12999 @command{login} from the Shadow tool suite.
13001 @item @code{login-arguments} (default: @code{'("-p")})
13002 A list of arguments to pass to @command{login}.
13004 @item @code{auto-login} (default: @code{#f})
13005 When passed a login name, as a string, the specified user will be logged
13006 in automatically without prompting for their login name or password.
13008 @item @code{hardware-acceleration?} (default: #f)
13009 Whether to use hardware acceleration.
13011 @item @code{kmscon} (default: @var{kmscon})
13012 The Kmscon package to use.
13017 @cindex name service cache daemon
13019 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
13020 [#:name-services '()]
13021 Return a service that runs the libc name service cache daemon (nscd) with the
13022 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
13023 Service Switch}, for an example.
13025 For convenience, the Shepherd service for nscd provides the following actions:
13029 @cindex cache invalidation, nscd
13030 @cindex nscd, cache invalidation
13031 This invalidate the given cache. For instance, running:
13034 herd invalidate nscd hosts
13038 invalidates the host name lookup cache of nscd.
13041 Running @command{herd statistics nscd} displays information about nscd usage
13047 @defvr {Scheme Variable} %nscd-default-configuration
13048 This is the default @code{<nscd-configuration>} value (see below) used
13049 by @code{nscd-service}. It uses the caches defined by
13050 @code{%nscd-default-caches}; see below.
13053 @deftp {Data Type} nscd-configuration
13054 This is the data type representing the name service cache daemon (nscd)
13059 @item @code{name-services} (default: @code{'()})
13060 List of packages denoting @dfn{name services} that must be visible to
13061 the nscd---e.g., @code{(list @var{nss-mdns})}.
13063 @item @code{glibc} (default: @var{glibc})
13064 Package object denoting the GNU C Library providing the @command{nscd}
13067 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
13068 Name of the nscd log file. This is where debugging output goes when
13069 @code{debug-level} is strictly positive.
13071 @item @code{debug-level} (default: @code{0})
13072 Integer denoting the debugging levels. Higher numbers mean that more
13073 debugging output is logged.
13075 @item @code{caches} (default: @code{%nscd-default-caches})
13076 List of @code{<nscd-cache>} objects denoting things to be cached; see
13082 @deftp {Data Type} nscd-cache
13083 Data type representing a cache database of nscd and its parameters.
13087 @item @code{database}
13088 This is a symbol representing the name of the database to be cached.
13089 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
13090 @code{services}, which designate the corresponding NSS database
13091 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
13093 @item @code{positive-time-to-live}
13094 @itemx @code{negative-time-to-live} (default: @code{20})
13095 A number representing the number of seconds during which a positive or
13096 negative lookup result remains in cache.
13098 @item @code{check-files?} (default: @code{#t})
13099 Whether to check for updates of the files corresponding to
13102 For instance, when @var{database} is @code{hosts}, setting this flag
13103 instructs nscd to check for updates in @file{/etc/hosts} and to take
13106 @item @code{persistent?} (default: @code{#t})
13107 Whether the cache should be stored persistently on disk.
13109 @item @code{shared?} (default: @code{#t})
13110 Whether the cache should be shared among users.
13112 @item @code{max-database-size} (default: 32@tie{}MiB)
13113 Maximum size in bytes of the database cache.
13115 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
13116 @c settings, so leave them out.
13121 @defvr {Scheme Variable} %nscd-default-caches
13122 List of @code{<nscd-cache>} objects used by default by
13123 @code{nscd-configuration} (see above).
13125 It enables persistent and aggressive caching of service and host name
13126 lookups. The latter provides better host name lookup performance,
13127 resilience in the face of unreliable name servers, and also better
13128 privacy---often the result of host name lookups is in local cache, so
13129 external name servers do not even need to be queried.
13132 @anchor{syslog-configuration-type}
13135 @deftp {Data Type} syslog-configuration
13136 This data type represents the configuration of the syslog daemon.
13139 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
13140 The syslog daemon to use.
13142 @item @code{config-file} (default: @code{%default-syslog.conf})
13143 The syslog configuration file to use.
13148 @anchor{syslog-service}
13150 @deffn {Scheme Procedure} syslog-service @var{config}
13151 Return a service that runs a syslog daemon according to @var{config}.
13153 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
13154 information on the configuration file syntax.
13157 @defvr {Scheme Variable} guix-service-type
13158 This is the type of the service that runs the build daemon,
13159 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
13160 @code{guix-configuration} record as described below.
13163 @anchor{guix-configuration-type}
13164 @deftp {Data Type} guix-configuration
13165 This data type represents the configuration of the Guix build daemon.
13166 @xref{Invoking guix-daemon}, for more information.
13169 @item @code{guix} (default: @var{guix})
13170 The Guix package to use.
13172 @item @code{build-group} (default: @code{"guixbuild"})
13173 Name of the group for build user accounts.
13175 @item @code{build-accounts} (default: @code{10})
13176 Number of build user accounts to create.
13178 @item @code{authorize-key?} (default: @code{#t})
13179 @cindex substitutes, authorization thereof
13180 Whether to authorize the substitute keys listed in
13181 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
13182 (@pxref{Substitutes}).
13184 @vindex %default-authorized-guix-keys
13185 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
13186 The list of authorized key files for archive imports, as a list of
13187 string-valued gexps (@pxref{Invoking guix archive}). By default, it
13188 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
13190 @item @code{use-substitutes?} (default: @code{#t})
13191 Whether to use substitutes.
13193 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
13194 The list of URLs where to look for substitutes by default.
13196 @item @code{max-silent-time} (default: @code{0})
13197 @itemx @code{timeout} (default: @code{0})
13198 The number of seconds of silence and the number of seconds of activity,
13199 respectively, after which a build process times out. A value of zero
13200 disables the timeout.
13202 @item @code{log-compression} (default: @code{'bzip2})
13203 The type of compression used for build logs---one of @code{gzip},
13204 @code{bzip2}, or @code{none}.
13206 @item @code{extra-options} (default: @code{'()})
13207 List of extra command-line options for @command{guix-daemon}.
13209 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
13210 File where @command{guix-daemon}'s standard output and standard error
13213 @cindex HTTP proxy, for @code{guix-daemon}
13214 @cindex proxy, for @code{guix-daemon} HTTP access
13215 @item @code{http-proxy} (default: @code{#f})
13216 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
13217 derivations and substitutes.
13219 It is also possible to change the daemon's proxy at run time through the
13220 @code{set-http-proxy} action, which restarts it:
13223 herd set-http-proxy guix-daemon http://localhost:8118
13226 To clear the proxy settings, run:
13229 herd set-http-proxy guix-daemon
13232 @item @code{tmpdir} (default: @code{#f})
13233 A directory path where the @command{guix-daemon} will perform builds.
13238 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
13239 Run @var{udev}, which populates the @file{/dev} directory dynamically.
13240 udev rules can be provided as a list of files through the @var{rules}
13241 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
13242 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
13243 creation of such rule files.
13245 The @command{herd rules udev} command, as root, returns the name of the
13246 directory containing all the active udev rules.
13249 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
13250 Return a udev-rule file named @var{file-name} containing the rules
13251 defined by the @var{contents} literal.
13253 In the following example, a rule for a USB device is defined to be
13254 stored in the file @file{90-usb-thing.rules}. The rule runs a script
13255 upon detecting a USB device with a given product identifier.
13258 (define %example-udev-rule
13260 "90-usb-thing.rules"
13261 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
13262 "ATTR@{product@}==\"Example\", "
13263 "RUN+=\"/path/to/script\"")))
13267 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
13268 [#:groups @var{groups}]
13269 Return a service that extends @code{udev-service-type } with @var{rules}
13270 and @code{account-service-type} with @var{groups} as system groups.
13271 This works by creating a singleton service type
13272 @code{@var{name}-udev-rules}, of which the returned service is an
13275 Here we show how it can be used to extend @code{udev-service-type} with the
13276 previously defined rule @code{%example-udev-rule}.
13282 (cons (udev-rules-service 'usb-thing %example-udev-rule)
13283 %desktop-services)))
13287 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
13288 Return a udev file named @var{file-name} containing the rules defined
13289 within @var{file}, a file-like object.
13291 The following example showcases how we can use an existing rule file.
13294 (use-modules (guix download) ;for url-fetch
13295 (guix packages) ;for origin
13298 (define %android-udev-rules
13300 "51-android-udev.rules"
13301 (let ((version "20170910"))
13304 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
13305 "android-udev-rules/" version "/51-android.rules"))
13307 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
13311 Additionally, Guix package definitions can be included in @var{rules} in
13312 order to extend the udev rules with the definitions found under their
13313 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
13314 @var{file->udev-rule} example, we could have used the
13315 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
13316 packages android)} module.
13318 The following example shows how to use the @var{android-udev-rules}
13319 package so that the Android tool @command{adb} can detect devices
13320 without root privileges. It also details how to create the
13321 @code{adbusers} group, which is required for the proper functioning of
13322 the rules defined within the @code{android-udev-rules} package. To
13323 create such a group, we must define it both as part of the
13324 @code{supplementary-groups} of our @code{user-account} declaration, as
13325 well as in the @var{groups} of the @code{udev-rules-service} procedure.
13328 (use-modules (gnu packages android) ;for android-udev-rules
13329 (gnu system shadow) ;for user-group
13334 (users (cons (user-account
13336 (supplementary-groups
13337 '("adbusers" ;for adb
13338 "wheel" "netdev" "audio" "video")))))
13341 (cons (udev-rules-service 'android android-udev-rules
13342 #:groups '("adbusers"))
13343 %desktop-services)))
13346 @defvr {Scheme Variable} urandom-seed-service-type
13347 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
13348 when rebooting. It also tries to seed @file{/dev/urandom} from
13349 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
13353 @defvr {Scheme Variable} %random-seed-file
13354 This is the name of the file where some random bytes are saved by
13355 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
13356 It defaults to @file{/var/lib/random-seed}.
13361 @defvr {Scheme Variable} gpm-service-type
13362 This is the type of the service that runs GPM, the @dfn{general-purpose
13363 mouse daemon}, which provides mouse support to the Linux console. GPM
13364 allows users to use the mouse in the console, notably to select, copy,
13367 The value for services of this type must be a @code{gpm-configuration}
13368 (see below). This service is not part of @code{%base-services}.
13371 @deftp {Data Type} gpm-configuration
13372 Data type representing the configuration of GPM.
13375 @item @code{options} (default: @code{%default-gpm-options})
13376 Command-line options passed to @command{gpm}. The default set of
13377 options instruct @command{gpm} to listen to mouse events on
13378 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
13381 @item @code{gpm} (default: @code{gpm})
13382 The GPM package to use.
13387 @anchor{guix-publish-service-type}
13388 @deffn {Scheme Variable} guix-publish-service-type
13389 This is the service type for @command{guix publish} (@pxref{Invoking
13390 guix publish}). Its value must be a @code{guix-publish-configuration}
13391 object, as described below.
13393 This assumes that @file{/etc/guix} already contains a signing key pair as
13394 created by @command{guix archive --generate-key} (@pxref{Invoking guix
13395 archive}). If that is not the case, the service will fail to start.
13398 @deftp {Data Type} guix-publish-configuration
13399 Data type representing the configuration of the @code{guix publish}
13403 @item @code{guix} (default: @code{guix})
13404 The Guix package to use.
13406 @item @code{port} (default: @code{80})
13407 The TCP port to listen for connections.
13409 @item @code{host} (default: @code{"localhost"})
13410 The host (and thus, network interface) to listen to. Use
13411 @code{"0.0.0.0"} to listen on all the network interfaces.
13413 @item @code{compression} (default: @code{'(("gzip" 3))})
13414 This is a list of compression method/level tuple used when compressing
13415 substitutes. For example, to compress all substitutes with @emph{both} lzip
13416 at level 7 and gzip at level 9, write:
13419 '(("lzip" 7) ("gzip" 9))
13422 Level 9 achieves the best compression ratio at the expense of increased CPU
13423 usage, whereas level 1 achieves fast compression.
13425 An empty list disables compression altogether.
13427 @item @code{nar-path} (default: @code{"nar"})
13428 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
13429 publish, @option{--nar-path}}, for details.
13431 @item @code{cache} (default: @code{#f})
13432 When it is @code{#f}, disable caching and instead generate archives on
13433 demand. Otherwise, this should be the name of a directory---e.g.,
13434 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
13435 archives and meta-data ready to be sent. @xref{Invoking guix publish,
13436 @option{--cache}}, for more information on the tradeoffs involved.
13438 @item @code{workers} (default: @code{#f})
13439 When it is an integer, this is the number of worker threads used for
13440 caching; when @code{#f}, the number of processors is used.
13441 @xref{Invoking guix publish, @option{--workers}}, for more information.
13443 @item @code{ttl} (default: @code{#f})
13444 When it is an integer, this denotes the @dfn{time-to-live} in seconds
13445 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
13446 for more information.
13450 @anchor{rngd-service}
13451 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
13452 [#:device "/dev/hwrng"]
13453 Return a service that runs the @command{rngd} program from @var{rng-tools}
13454 to add @var{device} to the kernel's entropy pool. The service will fail if
13455 @var{device} does not exist.
13458 @anchor{pam-limits-service}
13459 @cindex session limits
13464 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
13466 Return a service that installs a configuration file for the
13467 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
13468 @code{pam_limits} module}. The procedure optionally takes a list of
13469 @code{pam-limits-entry} values, which can be used to specify
13470 @code{ulimit} limits and nice priority limits to user sessions.
13472 The following limits definition sets two hard and soft limits for all
13473 login sessions of users in the @code{realtime} group:
13476 (pam-limits-service
13478 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
13479 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
13482 The first entry increases the maximum realtime priority for
13483 non-privileged processes; the second entry lifts any restriction of the
13484 maximum address space that can be locked in memory. These settings are
13485 commonly used for real-time audio systems.
13488 @node Scheduled Job Execution
13489 @subsection Scheduled Job Execution
13493 @cindex scheduling jobs
13494 The @code{(gnu services mcron)} module provides an interface to
13495 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
13496 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
13497 Unix @command{cron} daemon; the main difference is that it is
13498 implemented in Guile Scheme, which provides a lot of flexibility when
13499 specifying the scheduling of jobs and their actions.
13501 The example below defines an operating system that runs the
13502 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
13503 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
13504 well as the @command{mkid} command on behalf of an unprivileged user
13505 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
13506 gexps to introduce job definitions that are passed to mcron
13507 (@pxref{G-Expressions}).
13510 (use-modules (guix) (gnu) (gnu services mcron))
13511 (use-package-modules base idutils)
13513 (define updatedb-job
13514 ;; Run 'updatedb' at 3AM every day. Here we write the
13515 ;; job's action as a Scheme procedure.
13516 #~(job '(next-hour '(3))
13518 (execl (string-append #$findutils "/bin/updatedb")
13520 "--prunepaths=/tmp /var/tmp /gnu/store"))))
13522 (define garbage-collector-job
13523 ;; Collect garbage 5 minutes after midnight every day.
13524 ;; The job's action is a shell command.
13525 #~(job "5 0 * * *" ;Vixie cron syntax
13528 (define idutils-job
13529 ;; Update the index database as user "charlie" at 12:15PM
13530 ;; and 19:15PM. This runs from the user's home directory.
13531 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
13532 (string-append #$idutils "/bin/mkid src")
13537 (services (cons (service mcron-service-type
13538 (mcron-configuration
13539 (jobs (list garbage-collector-job
13545 For more complex jobs defined in Scheme where you need control over the top
13546 level, for instance to introduce a @code{use-modules} form, you can move your
13547 code to a separate program using the @code{program-file} procedure of the
13548 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
13552 (define %battery-alert-job
13553 ;; Beep when the battery percentage falls below %MIN-LEVEL.
13555 '(next-minute (range 0 60 1))
13557 "battery-alert.scm"
13558 (with-imported-modules (source-module-closure
13559 '((guix build utils)))
13561 (define %min-level 20)
13562 (use-modules (guix build utils)
13565 (ice-9 textual-ports)
13567 (setenv "LC_ALL" "C") ;ensure English output
13568 (and-let* ((input-pipe (open-pipe*
13570 #$(file-append acpi "/bin/acpi")))
13571 (output (get-string-all input-pipe))
13572 (m (string-match "Discharging, ([0-9]+)%" output))
13573 (level (string->number (match:substring m 1)))
13574 ((< level %min-level)))
13575 (format #t "warning: Battery level is low (~a%)~%" level)
13576 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
13579 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
13580 for more information on mcron job specifications. Below is the
13581 reference of the mcron service.
13583 On a running system, you can use the @code{schedule} action of the service to
13584 visualize the mcron jobs that will be executed next:
13587 # herd schedule mcron
13591 The example above lists the next five tasks that will be executed, but you can
13592 also specify the number of tasks to display:
13595 # herd schedule mcron 10
13598 @defvr {Scheme Variable} mcron-service-type
13599 This is the type of the @code{mcron} service, whose value is an
13600 @code{mcron-configuration} object.
13602 This service type can be the target of a service extension that provides
13603 it additional job specifications (@pxref{Service Composition}). In
13604 other words, it is possible to define services that provide additional
13608 @deftp {Data Type} mcron-configuration
13609 Data type representing the configuration of mcron.
13612 @item @code{mcron} (default: @var{mcron})
13613 The mcron package to use.
13616 This is a list of gexps (@pxref{G-Expressions}), where each gexp
13617 corresponds to an mcron job specification (@pxref{Syntax, mcron job
13618 specifications,, mcron, GNU@tie{}mcron}).
13624 @subsection Log Rotation
13627 @cindex log rotation
13629 Log files such as those found in @file{/var/log} tend to grow endlessly,
13630 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
13631 their contents in separate files, possibly compressed. The @code{(gnu
13632 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
13633 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
13635 This service is part of @code{%base-services}, and thus enabled by
13636 default, with the default settings, for commonly encountered log files.
13637 The example below shows how to extend it with an additional
13638 @dfn{rotation}, should you need to do that (usually, services that
13639 produce log files already take care of that):
13642 (use-modules (guix) (gnu))
13643 (use-service-modules admin)
13645 (define my-log-files
13646 ;; Log files that I want to rotate.
13647 '("/var/log/something.log" "/var/log/another.log"))
13651 (services (cons (simple-service 'rotate-my-stuff
13652 rottlog-service-type
13653 (list (log-rotation
13655 (files my-log-files))))
13659 @defvr {Scheme Variable} rottlog-service-type
13660 This is the type of the Rottlog service, whose value is a
13661 @code{rottlog-configuration} object.
13663 Other services can extend this one with new @code{log-rotation} objects
13664 (see below), thereby augmenting the set of files to be rotated.
13666 This service type can define mcron jobs (@pxref{Scheduled Job
13667 Execution}) to run the rottlog service.
13670 @deftp {Data Type} rottlog-configuration
13671 Data type representing the configuration of rottlog.
13674 @item @code{rottlog} (default: @code{rottlog})
13675 The Rottlog package to use.
13677 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
13678 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
13679 rottlog, GNU Rot[t]log Manual}).
13681 @item @code{rotations} (default: @code{%default-rotations})
13682 A list of @code{log-rotation} objects as defined below.
13685 This is a list of gexps where each gexp corresponds to an mcron job
13686 specification (@pxref{Scheduled Job Execution}).
13690 @deftp {Data Type} log-rotation
13691 Data type representing the rotation of a group of log files.
13693 Taking an example from the Rottlog manual (@pxref{Period Related File
13694 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
13700 (files '("/var/log/apache/*"))
13701 (options '("storedir apache-archives"
13707 The list of fields is as follows:
13710 @item @code{frequency} (default: @code{'weekly})
13711 The log rotation frequency, a symbol.
13714 The list of files or file glob patterns to rotate.
13716 @item @code{options} (default: @code{'()})
13717 The list of rottlog options for this rotation (@pxref{Configuration
13718 parameters,,, rottlog, GNU Rot[t]lg Manual}).
13720 @item @code{post-rotate} (default: @code{#f})
13721 Either @code{#f} or a gexp to execute once the rotation has completed.
13725 @defvr {Scheme Variable} %default-rotations
13726 Specifies weekly rotation of @code{%rotated-files} and of
13727 @file{/var/log/guix-daemon.log}.
13730 @defvr {Scheme Variable} %rotated-files
13731 The list of syslog-controlled files to be rotated. By default it is:
13732 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
13733 "/var/log/maillog")}.
13736 @node Networking Services
13737 @subsection Networking Services
13739 The @code{(gnu services networking)} module provides services to configure
13740 the network interface.
13742 @cindex DHCP, networking service
13743 @defvr {Scheme Variable} dhcp-client-service-type
13744 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
13745 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
13746 is the DHCP client package to use, @code{isc-dhcp} by default.
13749 @deffn {Scheme Procedure} dhcpd-service-type
13750 This type defines a service that runs a DHCP daemon. To create a
13751 service of this type, you must supply a @code{<dhcpd-configuration>}.
13755 (service dhcpd-service-type
13756 (dhcpd-configuration
13757 (config-file (local-file "my-dhcpd.conf"))
13758 (interfaces '("enp0s25"))))
13762 @deftp {Data Type} dhcpd-configuration
13764 @item @code{package} (default: @code{isc-dhcp})
13765 The package that provides the DHCP daemon. This package is expected to
13766 provide the daemon at @file{sbin/dhcpd} relative to its output
13767 directory. The default package is the
13768 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
13769 @item @code{config-file} (default: @code{#f})
13770 The configuration file to use. This is required. It will be passed to
13771 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
13772 object (@pxref{G-Expressions, file-like objects}). See @code{man
13773 dhcpd.conf} for details on the configuration file syntax.
13774 @item @code{version} (default: @code{"4"})
13775 The DHCP version to use. The ISC DHCP server supports the values ``4'',
13776 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
13777 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
13779 @item @code{run-directory} (default: @code{"/run/dhcpd"})
13780 The run directory to use. At service activation time, this directory
13781 will be created if it does not exist.
13782 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
13783 The PID file to use. This corresponds to the @code{-pf} option of
13784 @code{dhcpd}. See @code{man dhcpd} for details.
13785 @item @code{interfaces} (default: @code{'()})
13786 The names of the network interfaces on which dhcpd should listen for
13787 broadcasts. If this list is not empty, then its elements (which must be
13788 strings) will be appended to the @code{dhcpd} invocation when starting
13789 the daemon. It may not be necessary to explicitly specify any
13790 interfaces here; see @code{man dhcpd} for details.
13794 @defvr {Scheme Variable} static-networking-service-type
13795 This is the type for statically-configured network interfaces.
13796 @c TODO Document <static-networking> data structures.
13799 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
13800 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
13801 [#:requirement @code{'(udev)}]
13802 Return a service that starts @var{interface} with address @var{ip}. If
13803 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
13804 it must be a string specifying the default network gateway. @var{requirement}
13805 can be used to declare a dependency on another service before configuring the
13808 This procedure can be called several times, one for each network
13809 interface of interest. Behind the scenes what it does is extend
13810 @code{static-networking-service-type} with additional network interfaces
13816 (static-networking-service "eno1" "192.168.1.82"
13817 #:gateway "192.168.1.2"
13818 #:name-servers '("192.168.1.2"))
13825 @cindex network management
13826 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
13827 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
13828 management daemon that aims to simplify wired and wireless networking.
13830 This service adds the @var{wicd} package to the global profile, providing
13831 several commands to interact with the daemon and configure networking:
13832 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
13833 and @command{wicd-curses} user interfaces.
13836 @cindex ModemManager
13838 @defvr {Scheme Variable} modem-manager-service-type
13839 This is the service type for the
13840 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
13841 service. The value for this service type is a
13842 @code{modem-manager-configuration} record.
13844 This service is part of @code{%desktop-services} (@pxref{Desktop
13848 @deftp {Data Type} modem-manager-configuration
13849 Data type representing the configuration of ModemManager.
13852 @item @code{modem-manager} (default: @code{modem-manager})
13853 The ModemManager package to use.
13858 @cindex USB_ModeSwitch
13859 @cindex Modeswitching
13861 @defvr {Scheme Variable} usb-modeswitch-service-type
13862 This is the service type for the
13863 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
13864 value for this service type is a @code{usb-modeswitch-configuration} record.
13866 When plugged in, some USB modems (and other USB devices) initially present
13867 themselves as a read-only storage medium and not as a modem. They need to be
13868 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
13869 installs udev rules to automatically modeswitch these devices when they are
13872 This service is part of @code{%desktop-services} (@pxref{Desktop
13876 @deftp {Data Type} usb-modeswitch-configuration
13877 Data type representing the configuration of USB_ModeSwitch.
13880 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
13881 The USB_ModeSwitch package providing the binaries for modeswitching.
13883 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
13884 The package providing the device data and udev rules file used by
13887 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
13888 Which config file to use for the USB_ModeSwitch dispatcher. By default the
13889 config file shipped with USB_ModeSwitch is used which disables logging to
13890 @file{/var/log} among other default settings. If set to @code{#f}, no config
13896 @cindex NetworkManager
13898 @defvr {Scheme Variable} network-manager-service-type
13899 This is the service type for the
13900 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
13901 service. The value for this service type is a
13902 @code{network-manager-configuration} record.
13904 This service is part of @code{%desktop-services} (@pxref{Desktop
13908 @deftp {Data Type} network-manager-configuration
13909 Data type representing the configuration of NetworkManager.
13912 @item @code{network-manager} (default: @code{network-manager})
13913 The NetworkManager package to use.
13915 @item @code{dns} (default: @code{"default"})
13916 Processing mode for DNS, which affects how NetworkManager uses the
13917 @code{resolv.conf} configuration file.
13921 NetworkManager will update @code{resolv.conf} to reflect the nameservers
13922 provided by currently active connections.
13925 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
13926 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
13927 then update @code{resolv.conf} to point to the local nameserver.
13929 With this setting, you can share your network connection. For example when
13930 you want to share your network connection to another laptop @i{via} an
13931 Ethernet cable, you can open @command{nm-connection-editor} and configure the
13932 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
13933 and reestablish the connection (or reboot).
13935 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
13936 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
13937 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
13938 browser on your host system, or connect to the VM @i{via} SSH
13939 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
13940 host-to-guest connection, run this command once:
13943 nmcli connection add type tun \
13944 connection.interface-name tap0 \
13945 tun.mode tap tun.owner $(id -u) \
13946 ipv4.method shared \
13947 ipv4.addresses 172.28.112.1/24
13950 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
13951 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
13952 @command{qemu-system-...}.
13955 NetworkManager will not modify @code{resolv.conf}.
13958 @item @code{vpn-plugins} (default: @code{'()})
13959 This is the list of available plugins for virtual private networks
13960 (VPNs). An example of this is the @code{network-manager-openvpn}
13961 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
13967 @deffn {Scheme Variable} connman-service-type
13968 This is the service type to run @url{https://01.org/connman,Connman},
13969 a network connection manager.
13971 Its value must be an
13972 @code{connman-configuration} record as in this example:
13975 (service connman-service-type
13976 (connman-configuration
13977 (disable-vpn? #t)))
13980 See below for details about @code{connman-configuration}.
13983 @deftp {Data Type} connman-configuration
13984 Data Type representing the configuration of connman.
13987 @item @code{connman} (default: @var{connman})
13988 The connman package to use.
13990 @item @code{disable-vpn?} (default: @code{#f})
13991 When true, disable connman's vpn plugin.
13995 @cindex WPA Supplicant
13996 @defvr {Scheme Variable} wpa-supplicant-service-type
13997 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
13998 supplicant}, an authentication daemon required to authenticate against
13999 encrypted WiFi or ethernet networks.
14002 @deftp {Data Type} wpa-supplicant-configuration
14003 Data type representing the configuration of WPA Supplicant.
14005 It takes the following parameters:
14008 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
14009 The WPA Supplicant package to use.
14011 @item @code{dbus?} (default: @code{#t})
14012 Whether to listen for requests on D-Bus.
14014 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
14015 Where to store the PID file.
14017 @item @code{interface} (default: @code{#f})
14018 If this is set, it must specify the name of a network interface that
14019 WPA supplicant will control.
14021 @item @code{config-file} (default: @code{#f})
14022 Optional configuration file to use.
14024 @item @code{extra-options} (default: @code{'()})
14025 List of additional command-line arguments to pass to the daemon.
14029 @cindex hostapd service, for Wi-Fi access points
14030 @cindex Wi-Fi access points, hostapd service
14031 @defvr {Scheme Variable} hostapd-service-type
14032 This is the service type to run the @uref{https://w1.fi/hostapd/,
14033 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
14034 authentication servers. Its associated value must be a
14035 @code{hostapd-configuration} as shown below:
14038 ;; Use wlan1 to run the access point for "My Network".
14039 (service hostapd-service-type
14040 (hostapd-configuration
14041 (interface "wlan1")
14042 (ssid "My Network")
14047 @deftp {Data Type} hostapd-configuration
14048 This data type represents the configuration of the hostapd service, with
14049 the following fields:
14052 @item @code{package} (default: @code{hostapd})
14053 The hostapd package to use.
14055 @item @code{interface} (default: @code{"wlan0"})
14056 The network interface to run the WiFi access point.
14059 The SSID (@dfn{service set identifier}), a string that identifies this
14062 @item @code{broadcast-ssid?} (default: @code{#t})
14063 Whether to broadcast this SSID.
14065 @item @code{channel} (default: @code{1})
14066 The WiFi channel to use.
14068 @item @code{driver} (default: @code{"nl80211"})
14069 The driver interface type. @code{"nl80211"} is used with all Linux
14070 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
14071 RADIUS server that does # not control any wireless/wired driver.
14073 @item @code{extra-settings} (default: @code{""})
14074 Extra settings to append as-is to the hostapd configuration file. See
14075 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
14076 configuration file reference.
14080 @defvr {Scheme Variable} simulated-wifi-service-type
14081 This is the type of a service to simulate WiFi networking, which can be
14082 useful in virtual machines for testing purposes. The service loads the
14084 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
14085 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
14086 network that can be seen on @code{wlan0}, by default.
14088 The service's value is a @code{hostapd-configuration} record.
14092 @defvr {Scheme Variable} iptables-service-type
14093 This is the service type to set up an iptables configuration. iptables is a
14094 packet filtering framework supported by the Linux kernel. This service
14095 supports configuring iptables for both IPv4 and IPv6. A simple example
14096 configuration rejecting all incoming connections except those to the ssh port
14100 (service iptables-service-type
14101 (iptables-configuration
14102 (ipv4-rules (plain-file "iptables.rules" "*filter
14106 -A INPUT -p tcp --dport 22 -j ACCEPT
14107 -A INPUT -j REJECT --reject-with icmp-port-unreachable
14110 (ipv6-rules (plain-file "ip6tables.rules" "*filter
14114 -A INPUT -p tcp --dport 22 -j ACCEPT
14115 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
14121 @deftp {Data Type} iptables-configuration
14122 The data type representing the configuration of iptables.
14125 @item @code{iptables} (default: @code{iptables})
14126 The iptables package that provides @code{iptables-restore} and
14127 @code{ip6tables-restore}.
14128 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
14129 The iptables rules to use. It will be passed to @code{iptables-restore}.
14130 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
14132 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
14133 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
14134 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
14140 @defvr {Scheme Variable} nftables-service-type
14141 This is the service type to set up a nftables configuration. nftables is a
14142 netfilter project that aims to replace the existing iptables, ip6tables,
14143 arptables and ebtables framework. It provides a new packet filtering
14144 framework, a new user-space utility @command{nft}, and a compatibility layer
14145 for iptables. This service comes with a default ruleset
14146 @code{%default-nftables-ruleset} that rejecting all incomming connections
14147 except those to the ssh port 22. To use it, simply write:
14150 (service nftables-service-type)
14154 @deftp {Data Type} nftables-configuration
14155 The data type representing the configuration of nftables.
14158 @item @code{package} (default: @code{nftables})
14159 The nftables package that provides @command{nft}.
14160 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
14161 The nftables ruleset to use. This may be any ``file-like'' object
14162 (@pxref{G-Expressions, file-like objects}).
14166 @cindex NTP (Network Time Protocol), service
14167 @cindex ntpd, service for the Network Time Protocol daemon
14168 @cindex real time clock
14169 @defvr {Scheme Variable} ntp-service-type
14170 This is the type of the service running the @uref{https://www.ntp.org,
14171 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
14172 system clock synchronized with that of the specified NTP servers.
14174 The value of this service is an @code{ntpd-configuration} object, as described
14178 @deftp {Data Type} ntp-configuration
14179 This is the data type for the NTP service configuration.
14182 @item @code{servers} (default: @code{%ntp-servers})
14183 This is the list of servers (@code{<ntp-server>} records) with which
14184 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
14187 @item @code{allow-large-adjustment?} (default: @code{#t})
14188 This determines whether @command{ntpd} is allowed to make an initial
14189 adjustment of more than 1,000 seconds.
14191 @item @code{ntp} (default: @code{ntp})
14192 The NTP package to use.
14196 @defvr {Scheme Variable} %ntp-servers
14197 List of host names used as the default NTP servers. These are servers of the
14198 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
14201 @deftp {Data Type} ntp-server
14202 The data type representing the configuration of a NTP server.
14205 @item @code{type} (default: @code{'server})
14206 The type of the NTP server, given as a symbol. One of @code{'pool},
14207 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
14209 @item @code{address}
14210 The address of the server, as a string.
14212 @item @code{options}
14213 NTPD options to use with that specific server, given as a list of option names
14214 and/or of option names and values tuples. The following example define a server
14215 to use with the options @option{iburst} and @option{prefer}, as well as
14216 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
14221 (address "some.ntp.server.org")
14222 (options `(iburst (version 3) (maxpoll 16) prefer))))
14228 @deffn {Scheme Procedure} openntpd-service-type
14229 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
14230 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
14231 clock synchronized with that of the given servers.
14235 openntpd-service-type
14236 (openntpd-configuration
14237 (listen-on '("127.0.0.1" "::1"))
14238 (sensor '("udcf0 correction 70000"))
14239 (constraint-from '("www.gnu.org"))
14240 (constraints-from '("https://www.google.com/"))
14241 (allow-large-adjustment? #t)))
14246 @defvr {Scheme Variable} %openntpd-servers
14247 This variable is a list of the server addresses defined in
14248 @code{%ntp-servers}.
14251 @deftp {Data Type} openntpd-configuration
14253 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
14254 The openntpd executable to use.
14255 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
14256 A list of local IP addresses or hostnames the ntpd daemon should listen on.
14257 @item @code{query-from} (default: @code{'()})
14258 A list of local IP address the ntpd daemon should use for outgoing queries.
14259 @item @code{sensor} (default: @code{'()})
14260 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
14261 will listen to each sensor that actually exists and ignore non-existent ones.
14262 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
14264 @item @code{server} (default: @code{'()})
14265 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
14266 @item @code{servers} (default: @code{%openntp-servers})
14267 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
14268 @item @code{constraint-from} (default: @code{'()})
14269 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
14270 This time information is not used for precision but acts as an authenticated
14271 constraint, thereby reducing the impact of unauthenticated NTP
14272 man-in-the-middle attacks.
14273 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
14275 @item @code{constraints-from} (default: @code{'()})
14276 As with constraint from, specify a list of URLs, IP addresses or hostnames of
14277 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
14278 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
14279 @item @code{allow-large-adjustment?} (default: @code{#f})
14280 Determines if @code{ntpd} is allowed to make an initial adjustment of more
14286 @deffn {Scheme variable} inetd-service-type
14287 This service runs the @command{inetd} (@pxref{inetd invocation,,,
14288 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
14289 connections on internet sockets, and lazily starts the specified server
14290 program when a connection is made on one of these sockets.
14292 The value of this service is an @code{inetd-configuration} object. The
14293 following example configures the @command{inetd} daemon to provide the
14294 built-in @command{echo} service, as well as an smtp service which
14295 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
14296 gateway @code{hostname}:
14301 (inetd-configuration
14305 (socket-type 'stream)
14312 (socket-type 'stream)
14316 (program (file-append openssh "/bin/ssh"))
14318 '("ssh" "-qT" "-i" "/path/to/ssh_key"
14319 "-W" "smtp-server:25" "user@@hostname")))))))
14322 See below for more details about @code{inetd-configuration}.
14325 @deftp {Data Type} inetd-configuration
14326 Data type representing the configuration of @command{inetd}.
14329 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
14330 The @command{inetd} executable to use.
14332 @item @code{entries} (default: @code{'()})
14333 A list of @command{inetd} service entries. Each entry should be created
14334 by the @code{inetd-entry} constructor.
14338 @deftp {Data Type} inetd-entry
14339 Data type representing an entry in the @command{inetd} configuration.
14340 Each entry corresponds to a socket where @command{inetd} will listen for
14344 @item @code{node} (default: @code{#f})
14345 Optional string, a comma-separated list of local addresses
14346 @command{inetd} should use when listening for this service.
14347 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
14348 description of all options.
14350 A string, the name must correspond to an entry in @code{/etc/services}.
14351 @item @code{socket-type}
14352 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
14354 @item @code{protocol}
14355 A string, must correspond to an entry in @code{/etc/protocols}.
14356 @item @code{wait?} (default: @code{#t})
14357 Whether @command{inetd} should wait for the server to exit before
14358 listening to new service requests.
14360 A string containing the user (and, optionally, group) name of the user
14361 as whom the server should run. The group name can be specified in a
14362 suffix, separated by a colon or period, i.e.@: @code{"user"},
14363 @code{"user:group"} or @code{"user.group"}.
14364 @item @code{program} (default: @code{"internal"})
14365 The server program which will serve the requests, or @code{"internal"}
14366 if @command{inetd} should use a built-in service.
14367 @item @code{arguments} (default: @code{'()})
14368 A list strings or file-like objects, which are the server program's
14369 arguments, starting with the zeroth argument, i.e.@: the name of the
14370 program itself. For @command{inetd}'s internal services, this entry
14371 must be @code{'()} or @code{'("internal")}.
14374 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
14375 detailed discussion of each configuration field.
14379 @defvr {Scheme Variable} tor-service-type
14380 This is the type for a service that runs the @uref{https://torproject.org,
14381 Tor} anonymous networking daemon. The service is configured using a
14382 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
14383 @code{tor} unprivileged user, which is a member of the @code{tor} group.
14387 @deftp {Data Type} tor-configuration
14389 @item @code{tor} (default: @code{tor})
14390 The package that provides the Tor daemon. This package is expected to provide
14391 the daemon at @file{bin/tor} relative to its output directory. The default
14392 package is the @uref{https://www.torproject.org, Tor Project's}
14395 @item @code{config-file} (default: @code{(plain-file "empty" "")})
14396 The configuration file to use. It will be appended to a default configuration
14397 file, and the final configuration file will be passed to @code{tor} via its
14398 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
14399 file-like objects}). See @code{man tor} for details on the configuration file
14402 @item @code{hidden-services} (default: @code{'()})
14403 The list of @code{<hidden-service>} records to use. For any hidden service
14404 you include in this list, appropriate configuration to enable the hidden
14405 service will be automatically added to the default configuration file. You
14406 may conveniently create @code{<hidden-service>} records using the
14407 @code{tor-hidden-service} procedure described below.
14409 @item @code{socks-socket-type} (default: @code{'tcp})
14410 The default socket type that Tor should use for its SOCKS socket. This must
14411 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
14412 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
14413 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
14414 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
14417 If you want to customize the SOCKS socket in more detail, leave
14418 @code{socks-socket-type} at its default value of @code{'tcp} and use
14419 @code{config-file} to override the default by providing your own
14420 @code{SocksPort} option.
14424 @cindex hidden service
14425 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
14426 Define a new Tor @dfn{hidden service} called @var{name} and implementing
14427 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
14430 '((22 "127.0.0.1:22")
14431 (80 "127.0.0.1:8080"))
14434 In this example, port 22 of the hidden service is mapped to local port 22, and
14435 port 80 is mapped to local port 8080.
14437 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
14438 the @file{hostname} file contains the @code{.onion} host name for the hidden
14441 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
14442 project's documentation} for more information.
14445 The @code{(gnu services rsync)} module provides the following services:
14447 You might want an rsync daemon if you have files that you want available
14448 so anyone (or just yourself) can download existing files or upload new
14451 @deffn {Scheme Variable} rsync-service-type
14452 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
14453 The value for this service type is a
14454 @command{rsync-configuration} record as in this example:
14457 (service rsync-service-type)
14460 See below for details about @code{rsync-configuration}.
14463 @deftp {Data Type} rsync-configuration
14464 Data type representing the configuration for @code{rsync-service}.
14467 @item @code{package} (default: @var{rsync})
14468 @code{rsync} package to use.
14470 @item @code{port-number} (default: @code{873})
14471 TCP port on which @command{rsync} listens for incoming connections. If port
14472 is less than @code{1024} @command{rsync} needs to be started as the
14473 @code{root} user and group.
14475 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
14476 Name of the file where @command{rsync} writes its PID.
14478 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
14479 Name of the file where @command{rsync} writes its lock file.
14481 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
14482 Name of the file where @command{rsync} writes its log file.
14484 @item @code{use-chroot?} (default: @var{#t})
14485 Whether to use chroot for @command{rsync} shared directory.
14487 @item @code{share-path} (default: @file{/srv/rsync})
14488 Location of the @command{rsync} shared directory.
14490 @item @code{share-comment} (default: @code{"Rsync share"})
14491 Comment of the @command{rsync} shared directory.
14493 @item @code{read-only?} (default: @var{#f})
14494 Read-write permissions to shared directory.
14496 @item @code{timeout} (default: @code{300})
14497 I/O timeout in seconds.
14499 @item @code{user} (default: @var{"root"})
14500 Owner of the @code{rsync} process.
14502 @item @code{group} (default: @var{"root"})
14503 Group of the @code{rsync} process.
14505 @item @code{uid} (default: @var{"rsyncd"})
14506 User name or user ID that file transfers to and from that module should take
14507 place as when the daemon was run as @code{root}.
14509 @item @code{gid} (default: @var{"rsyncd"})
14510 Group name or group ID that will be used when accessing the module.
14515 Furthermore, @code{(gnu services ssh)} provides the following services.
14519 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
14520 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
14521 [#:allow-empty-passwords? #f] [#:root-login? #f] @
14522 [#:syslog-output? #t] [#:x11-forwarding? #t] @
14523 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
14524 [#:public-key-authentication? #t] [#:initialize? #t]
14525 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
14526 @var{host-key} must designate a file containing the host key, and readable
14529 When @var{daemonic?} is true, @command{lshd} will detach from the
14530 controlling terminal and log its output to syslogd, unless one sets
14531 @var{syslog-output?} to false. Obviously, it also makes lsh-service
14532 depend on existence of syslogd service. When @var{pid-file?} is true,
14533 @command{lshd} writes its PID to the file called @var{pid-file}.
14535 When @var{initialize?} is true, automatically create the seed and host key
14536 upon service activation if they do not exist yet. This may take long and
14537 require interaction.
14539 When @var{initialize?} is false, it is up to the user to initialize the
14540 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
14541 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
14542 basics,,, lsh, LSH Manual}).
14544 When @var{interfaces} is empty, lshd listens for connections on all the
14545 network interfaces; otherwise, @var{interfaces} must be a list of host names
14548 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
14549 passwords, and @var{root-login?} specifies whether to accept log-ins as
14552 The other options should be self-descriptive.
14557 @deffn {Scheme Variable} openssh-service-type
14558 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
14559 shell daemon, @command{sshd}. Its value must be an
14560 @code{openssh-configuration} record as in this example:
14563 (service openssh-service-type
14564 (openssh-configuration
14565 (x11-forwarding? #t)
14566 (permit-root-login 'without-password)
14568 `(("alice" ,(local-file "alice.pub"))
14569 ("bob" ,(local-file "bob.pub"))))))
14572 See below for details about @code{openssh-configuration}.
14574 This service can be extended with extra authorized keys, as in this
14578 (service-extension openssh-service-type
14579 (const `(("charlie"
14580 ,(local-file "charlie.pub")))))
14584 @deftp {Data Type} openssh-configuration
14585 This is the configuration record for OpenSSH's @command{sshd}.
14588 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
14589 Name of the file where @command{sshd} writes its PID.
14591 @item @code{port-number} (default: @code{22})
14592 TCP port on which @command{sshd} listens for incoming connections.
14594 @item @code{permit-root-login} (default: @code{#f})
14595 This field determines whether and when to allow logins as root. If
14596 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
14597 If it's the symbol @code{'without-password}, then root logins are
14598 permitted but not with password-based authentication.
14600 @item @code{allow-empty-passwords?} (default: @code{#f})
14601 When true, users with empty passwords may log in. When false, they may
14604 @item @code{password-authentication?} (default: @code{#t})
14605 When true, users may log in with their password. When false, they have
14606 other authentication methods.
14608 @item @code{public-key-authentication?} (default: @code{#t})
14609 When true, users may log in using public key authentication. When
14610 false, users have to use other authentication method.
14612 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
14613 This is used only by protocol version 2.
14615 @item @code{x11-forwarding?} (default: @code{#f})
14616 When true, forwarding of X11 graphical client connections is
14617 enabled---in other words, @command{ssh} options @option{-X} and
14618 @option{-Y} will work.
14620 @item @code{allow-agent-forwarding?} (default: @code{#t})
14621 Whether to allow agent forwarding.
14623 @item @code{allow-tcp-forwarding?} (default: @code{#t})
14624 Whether to allow TCP forwarding.
14626 @item @code{gateway-ports?} (default: @code{#f})
14627 Whether to allow gateway ports.
14629 @item @code{challenge-response-authentication?} (default: @code{#f})
14630 Specifies whether challenge response authentication is allowed (e.g.@: via
14633 @item @code{use-pam?} (default: @code{#t})
14634 Enables the Pluggable Authentication Module interface. If set to
14635 @code{#t}, this will enable PAM authentication using
14636 @code{challenge-response-authentication?} and
14637 @code{password-authentication?}, in addition to PAM account and session
14638 module processing for all authentication types.
14640 Because PAM challenge response authentication usually serves an
14641 equivalent role to password authentication, you should disable either
14642 @code{challenge-response-authentication?} or
14643 @code{password-authentication?}.
14645 @item @code{print-last-log?} (default: @code{#t})
14646 Specifies whether @command{sshd} should print the date and time of the
14647 last user login when a user logs in interactively.
14649 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
14650 Configures external subsystems (e.g.@: file transfer daemon).
14652 This is a list of two-element lists, each of which containing the
14653 subsystem name and a command (with optional arguments) to execute upon
14656 The command @command{internal-sftp} implements an in-process SFTP
14657 server. Alternatively, one can specify the @command{sftp-server} command:
14659 (service openssh-service-type
14660 (openssh-configuration
14662 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
14665 @item @code{accepted-environment} (default: @code{'()})
14666 List of strings describing which environment variables may be exported.
14668 Each string gets on its own line. See the @code{AcceptEnv} option in
14669 @code{man sshd_config}.
14671 This example allows ssh-clients to export the @env{COLORTERM} variable.
14672 It is set by terminal emulators, which support colors. You can use it in
14673 your shell's resource file to enable colors for the prompt and commands
14674 if this variable is set.
14677 (service openssh-service-type
14678 (openssh-configuration
14679 (accepted-environment '("COLORTERM"))))
14682 @item @code{authorized-keys} (default: @code{'()})
14683 @cindex authorized keys, SSH
14684 @cindex SSH authorized keys
14685 This is the list of authorized keys. Each element of the list is a user
14686 name followed by one or more file-like objects that represent SSH public
14690 (openssh-configuration
14692 `(("rekado" ,(local-file "rekado.pub"))
14693 ("chris" ,(local-file "chris.pub"))
14694 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
14698 registers the specified public keys for user accounts @code{rekado},
14699 @code{chris}, and @code{root}.
14701 Additional authorized keys can be specified @i{via}
14702 @code{service-extension}.
14704 Note that this does @emph{not} interfere with the use of
14705 @file{~/.ssh/authorized_keys}.
14707 @item @code{log-level} (default: @code{'info})
14708 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
14709 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
14710 page for @file{sshd_config} for the full list of level names.
14712 @item @code{extra-content} (default: @code{""})
14713 This field can be used to append arbitrary text to the configuration file. It
14714 is especially useful for elaborate configurations that cannot be expressed
14715 otherwise. This configuration, for example, would generally disable root
14716 logins, but permit them from one specific IP address:
14719 (openssh-configuration
14721 Match Address 192.168.0.1
14722 PermitRootLogin yes"))
14728 @deffn {Scheme Procedure} dropbear-service [@var{config}]
14729 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
14730 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
14733 For example, to specify a Dropbear service listening on port 1234, add
14734 this call to the operating system's @code{services} field:
14737 (dropbear-service (dropbear-configuration
14738 (port-number 1234)))
14742 @deftp {Data Type} dropbear-configuration
14743 This data type represents the configuration of a Dropbear SSH daemon.
14746 @item @code{dropbear} (default: @var{dropbear})
14747 The Dropbear package to use.
14749 @item @code{port-number} (default: 22)
14750 The TCP port where the daemon waits for incoming connections.
14752 @item @code{syslog-output?} (default: @code{#t})
14753 Whether to enable syslog output.
14755 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
14756 File name of the daemon's PID file.
14758 @item @code{root-login?} (default: @code{#f})
14759 Whether to allow @code{root} logins.
14761 @item @code{allow-empty-passwords?} (default: @code{#f})
14762 Whether to allow empty passwords.
14764 @item @code{password-authentication?} (default: @code{#t})
14765 Whether to enable password-based authentication.
14770 @deffn {Scheme Variable} autossh-service-type
14771 This is the type for the @uref{https://www.harding.motd.ca/autossh,
14772 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
14773 restarting it as necessary should it die or stop passing traffic.
14774 AutoSSH can be run manually from the command-line by passing arguments
14775 to the binary @command{autossh} from the package @code{autossh}, but it
14776 can also be run as a Guix service. This latter use case is documented
14779 AutoSSH can be used to forward local traffic to a remote machine using
14780 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
14783 For example, to specify a service running autossh as the user
14784 @code{pino} and forwarding all local connections to port @code{8081} to
14785 @code{remote:8081} using an SSH tunnel, add this call to the operating
14786 system's @code{services} field:
14789 (service autossh-service-type
14790 (autossh-configuration
14792 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
14796 @deftp {Data Type} autossh-configuration
14797 This data type represents the configuration of an AutoSSH service.
14801 @item @code{user} (default @code{"autossh"})
14802 The user as which the AutoSSH service is to be run.
14803 This assumes that the specified user exists.
14805 @item @code{poll} (default @code{600})
14806 Specifies the connection poll time in seconds.
14808 @item @code{first-poll} (default @code{#f})
14809 Specifies how many seconds AutoSSH waits before the first connection
14810 test. After this first test, polling is resumed at the pace defined in
14811 @code{poll}. When set to @code{#f}, the first poll is not treated
14812 specially and will also use the connection poll specified in
14815 @item @code{gate-time} (default @code{30})
14816 Specifies how many seconds an SSH connection must be active before it is
14817 considered successful.
14819 @item @code{log-level} (default @code{1})
14820 The log level, corresponding to the levels used by syslog---so @code{0}
14821 is the most silent while @code{7} is the chattiest.
14823 @item @code{max-start} (default @code{#f})
14824 The maximum number of times SSH may be (re)started before AutoSSH exits.
14825 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
14827 @item @code{message} (default @code{""})
14828 The message to append to the echo message sent when testing connections.
14830 @item @code{port} (default @code{"0"})
14831 The ports used for monitoring the connection. When set to @code{"0"},
14832 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
14833 a positive integer, ports @var{n} and @var{n}+1 are used for
14834 monitoring the connection, such that port @var{n} is the base
14835 monitoring port and @code{n+1} is the echo port. When set to
14836 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
14837 integers, the ports @var{n} and @var{n}+1 are used for monitoring the
14838 connection, such that port @var{n} is the base monitoring port and
14839 @var{m} is the echo port.
14841 @item @code{ssh-options} (default @code{'()})
14842 The list of command-line arguments to pass to @command{ssh} when it is
14843 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
14844 may cause undefined behaviour.
14849 @defvr {Scheme Variable} %facebook-host-aliases
14850 This variable contains a string for use in @file{/etc/hosts}
14851 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
14852 line contains a entry that maps a known server name of the Facebook
14853 on-line service---e.g., @code{www.facebook.com}---to the local
14854 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
14856 This variable is typically used in the @code{hosts-file} field of an
14857 @code{operating-system} declaration (@pxref{operating-system Reference,
14858 @file{/etc/hosts}}):
14861 (use-modules (gnu) (guix))
14864 (host-name "mymachine")
14867 ;; Create a /etc/hosts file with aliases for "localhost"
14868 ;; and "mymachine", as well as for Facebook servers.
14869 (plain-file "hosts"
14870 (string-append (local-host-aliases host-name)
14871 %facebook-host-aliases))))
14874 This mechanism can prevent programs running locally, such as Web
14875 browsers, from accessing Facebook.
14878 The @code{(gnu services avahi)} provides the following definition.
14880 @defvr {Scheme Variable} avahi-service-type
14881 This is the service that runs @command{avahi-daemon}, a system-wide
14882 mDNS/DNS-SD responder that allows for service discovery and
14883 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
14884 Its value must be a @code{zero-configuration} record---see below.
14886 This service extends the name service cache daemon (nscd) so that it can
14887 resolve @code{.local} host names using
14888 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
14889 Service Switch}, for information on host name resolution.
14891 Additionally, add the @var{avahi} package to the system profile so that
14892 commands such as @command{avahi-browse} are directly usable.
14895 @deftp {Data Type} avahi-configuration
14896 Data type representation the configuration for Avahi.
14900 @item @code{host-name} (default: @code{#f})
14901 If different from @code{#f}, use that as the host name to
14902 publish for this machine; otherwise, use the machine's actual host name.
14904 @item @code{publish?} (default: @code{#t})
14905 When true, allow host names and services to be published (broadcast) over the
14908 @item @code{publish-workstation?} (default: @code{#t})
14909 When true, @command{avahi-daemon} publishes the machine's host name and IP
14910 address via mDNS on the local network. To view the host names published on
14911 your local network, you can run:
14914 avahi-browse _workstation._tcp
14917 @item @code{wide-area?} (default: @code{#f})
14918 When true, DNS-SD over unicast DNS is enabled.
14920 @item @code{ipv4?} (default: @code{#t})
14921 @itemx @code{ipv6?} (default: @code{#t})
14922 These fields determine whether to use IPv4/IPv6 sockets.
14924 @item @code{domains-to-browse} (default: @code{'()})
14925 This is a list of domains to browse.
14929 @deffn {Scheme Variable} openvswitch-service-type
14930 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
14931 service, whose value should be an @code{openvswitch-configuration}
14935 @deftp {Data Type} openvswitch-configuration
14936 Data type representing the configuration of Open vSwitch, a multilayer
14937 virtual switch which is designed to enable massive network automation
14938 through programmatic extension.
14941 @item @code{package} (default: @var{openvswitch})
14942 Package object of the Open vSwitch.
14947 @defvr {Scheme Variable} pagekite-service-type
14948 This is the service type for the @uref{https://pagekite.net, PageKite} service,
14949 a tunneling solution for making localhost servers publicly visible, even from
14950 behind restrictive firewalls or NAT without forwarded ports. The value for
14951 this service type is a @code{pagekite-configuration} record.
14953 Here's an example exposing the local HTTP and SSH daemons:
14956 (service pagekite-service-type
14957 (pagekite-configuration
14958 (kites '("http:@@kitename:localhost:80:@@kitesecret"
14959 "raw/22:@@kitename:localhost:22:@@kitesecret"))
14960 (extra-file "/etc/pagekite.rc")))
14964 @deftp {Data Type} pagekite-configuration
14965 Data type representing the configuration of PageKite.
14968 @item @code{package} (default: @var{pagekite})
14969 Package object of PageKite.
14971 @item @code{kitename} (default: @code{#f})
14972 PageKite name for authenticating to the frontend server.
14974 @item @code{kitesecret} (default: @code{#f})
14975 Shared secret for authenticating to the frontend server. You should probably
14976 put this inside @code{extra-file} instead.
14978 @item @code{frontend} (default: @code{#f})
14979 Connect to the named PageKite frontend server instead of the
14980 @uref{https://pagekite.net,,pagekite.net} service.
14982 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
14983 List of service kites to use. Exposes HTTP on port 80 by default. The format
14984 is @code{proto:kitename:host:port:secret}.
14986 @item @code{extra-file} (default: @code{#f})
14987 Extra configuration file to read, which you are expected to create manually.
14988 Use this to add additional options and manage shared secrets out-of-band.
14994 @subsection X Window
14997 @cindex X Window System
14998 @cindex login manager
14999 Support for the X Window graphical display system---specifically
15000 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
15001 there is no @code{xorg-service} procedure. Instead, the X server is
15002 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
15005 @cindex GNOME, login manager
15006 GDM of course allows users to log in into window managers and desktop
15007 environments other than GNOME; for those using GNOME, GDM is required for
15008 features such as automatic screen locking.
15010 @cindex window manager
15011 To use X11, you must install at least one @dfn{window manager}---for
15012 example the @code{windowmaker} or @code{openbox} packages---preferably
15013 by adding it to the @code{packages} field of your operating system
15014 definition (@pxref{operating-system Reference, system-wide packages}).
15016 @defvr {Scheme Variable} gdm-service-type
15017 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
15018 Desktop Manager} (GDM), a program that manages graphical display servers and
15019 handles graphical user logins. Its value must be a @code{gdm-configuration}
15022 @cindex session types (X11)
15023 @cindex X11 session types
15024 GDM looks for @dfn{session types} described by the @file{.desktop} files in
15025 @file{/run/current-system/profile/share/xsessions} and allows users to choose
15026 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
15027 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
15028 set of packages automatically makes them available at the log-in screen.
15030 In addition, @file{~/.xsession} files are honored. When available,
15031 @file{~/.xsession} must be an executable that starts a window manager
15032 and/or other X clients.
15035 @deftp {Data Type} gdm-configuration
15037 @item @code{auto-login?} (default: @code{#f})
15038 @itemx @code{default-user} (default: @code{#f})
15039 When @code{auto-login?} is false, GDM presents a log-in screen.
15041 When @code{auto-login?} is true, GDM logs in directly as
15042 @code{default-user}.
15044 @item @code{debug?} (default: @code{#f})
15045 When true, GDM writes debug messages to its log.
15047 @item @code{gnome-shell-assets} (default: ...)
15048 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
15050 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
15051 Configuration of the Xorg graphical server.
15053 @item @code{xsession} (default: @code{(xinitrc)})
15054 Script to run before starting a X session.
15056 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
15057 File name of the @code{dbus-daemon} executable.
15059 @item @code{gdm} (default: @code{gdm})
15060 The GDM package to use.
15064 @defvr {Scheme Variable} slim-service-type
15065 This is the type for the SLiM graphical login manager for X11.
15067 Like GDM, SLiM looks for session types described by @file{.desktop} files and
15068 allows users to choose a session from the log-in screen using @kbd{F1}. It
15069 also honors @file{~/.xsession} files.
15071 Unlike GDM, SLiM does not spawn the user session on a different VT after
15072 logging in, which means that you can only start one graphical session. If you
15073 want to be able to run multiple graphical sessions at the same time you have
15074 to add multiple SLiM services to your system services. The following example
15075 shows how to replace the default GDM service with two SLiM services on tty7
15079 (use-modules (gnu services)
15080 (gnu services desktop)
15081 (gnu services xorg)
15082 (srfi srfi-1)) ;for 'remove'
15086 (services (cons* (service slim-service-type (slim-configuration
15089 (service slim-service-type (slim-configuration
15092 (remove (lambda (service)
15093 (eq? (service-kind service) gdm-service-type))
15094 %desktop-services))))
15099 @deftp {Data Type} slim-configuration
15100 Data type representing the configuration of @code{slim-service-type}.
15103 @item @code{allow-empty-passwords?} (default: @code{#t})
15104 Whether to allow logins with empty passwords.
15106 @item @code{auto-login?} (default: @code{#f})
15107 @itemx @code{default-user} (default: @code{""})
15108 When @code{auto-login?} is false, SLiM presents a log-in screen.
15110 When @code{auto-login?} is true, SLiM logs in directly as
15111 @code{default-user}.
15113 @item @code{theme} (default: @code{%default-slim-theme})
15114 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
15115 The graphical theme to use and its name.
15117 @item @code{auto-login-session} (default: @code{#f})
15118 If true, this must be the name of the executable to start as the default
15119 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
15121 If false, a session described by one of the available @file{.desktop}
15122 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
15126 You must install at least one window manager in the system profile or in
15127 your user profile. Failing to do that, if @code{auto-login-session} is
15128 false, you will be unable to log in.
15131 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
15132 Configuration of the Xorg graphical server.
15134 @item @code{display} (default @code{":0"})
15135 The display on which to start the Xorg graphical server.
15137 @item @code{vt} (default @code{"vt7"})
15138 The VT on which to start the Xorg graphical server.
15140 @item @code{xauth} (default: @code{xauth})
15141 The XAuth package to use.
15143 @item @code{shepherd} (default: @code{shepherd})
15144 The Shepherd package used when invoking @command{halt} and
15147 @item @code{sessreg} (default: @code{sessreg})
15148 The sessreg package used in order to register the session.
15150 @item @code{slim} (default: @code{slim})
15151 The SLiM package to use.
15155 @defvr {Scheme Variable} %default-theme
15156 @defvrx {Scheme Variable} %default-theme-name
15157 The default SLiM theme and its name.
15161 @deftp {Data Type} sddm-configuration
15162 This is the data type representing the SDDM service configuration.
15165 @item @code{display-server} (default: "x11")
15166 Select display server to use for the greeter. Valid values are
15167 @samp{"x11"} or @samp{"wayland"}.
15169 @item @code{numlock} (default: "on")
15170 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
15172 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
15173 Command to run when halting.
15175 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
15176 Command to run when rebooting.
15178 @item @code{theme} (default "maldives")
15179 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
15180 @samp{"maldives"} or @samp{"maya"}.
15182 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
15183 Directory to look for themes.
15185 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
15186 Directory to look for faces.
15188 @item @code{default-path} (default "/run/current-system/profile/bin")
15189 Default PATH to use.
15191 @item @code{minimum-uid} (default: 1000)
15192 Minimum UID displayed in SDDM and allowed for log-in.
15194 @item @code{maximum-uid} (default: 2000)
15195 Maximum UID to display in SDDM.
15197 @item @code{remember-last-user?} (default #t)
15198 Remember last user.
15200 @item @code{remember-last-session?} (default #t)
15201 Remember last session.
15203 @item @code{hide-users} (default "")
15204 Usernames to hide from SDDM greeter.
15206 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
15207 Users with shells listed will be hidden from the SDDM greeter.
15209 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
15210 Script to run before starting a wayland session.
15212 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
15213 Directory to look for desktop files starting wayland sessions.
15215 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
15216 Configuration of the Xorg graphical server.
15218 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
15221 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
15224 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
15225 Script to run after starting xorg-server.
15227 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
15228 Script to run before stopping xorg-server.
15230 @item @code{xsession-command} (default: @code{xinitrc})
15231 Script to run before starting a X session.
15233 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
15234 Directory to look for desktop files starting X sessions.
15236 @item @code{minimum-vt} (default: 7)
15239 @item @code{auto-login-user} (default "")
15240 User to use for auto-login.
15242 @item @code{auto-login-session} (default "")
15243 Desktop file to use for auto-login.
15245 @item @code{relogin?} (default #f)
15246 Relogin after logout.
15251 @cindex login manager
15253 @defvr {Scheme Variable} sddm-service-type
15254 This is the type of the service to run the
15255 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
15256 must be a @code{sddm-configuration} record (see below).
15258 Here's an example use:
15261 (service sddm-service-type
15262 (sddm-configuration
15263 (auto-login-user "alice")
15264 (auto-login-session "xfce.desktop")))
15268 @deftp {Data Type} sddm-configuration
15269 This data type represents the configuration of the SDDM login manager.
15270 The available fields are:
15273 @item @code{sddm} (default: @code{sddm})
15274 The SDDM package to use.
15276 @item @code{display-server} (default: @code{"x11"})
15277 This must be either @code{"x11"} or @code{"wayland"}.
15279 @c FIXME: Add more fields.
15281 @item @code{auto-login-user} (default: @code{""})
15282 If non-empty, this is the user account under which to log in
15285 @item @code{auto-login-session} (default: @code{""})
15286 If non-empty, this is the @file{.desktop} file name to use as the
15287 auto-login session.
15291 @cindex Xorg, configuration
15292 @deftp {Data Type} xorg-configuration
15293 This data type represents the configuration of the Xorg graphical display
15294 server. Note that there is not Xorg service; instead, the X server is started
15295 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
15296 of these display managers aggregates an @code{xorg-configuration} record.
15299 @item @code{modules} (default: @code{%default-xorg-modules})
15300 This is a list of @dfn{module packages} loaded by the Xorg
15301 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
15303 @item @code{fonts} (default: @code{%default-xorg-fonts})
15304 This is a list of font directories to add to the server's @dfn{font path}.
15306 @item @code{drivers} (default: @code{'()})
15307 This must be either the empty list, in which case Xorg chooses a graphics
15308 driver automatically, or a list of driver names that will be tried in this
15309 order---e.g., @code{("modesetting" "vesa")}.
15311 @item @code{resolutions} (default: @code{'()})
15312 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
15313 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
15316 @cindex keyboard layout, for Xorg
15317 @cindex keymap, for Xorg
15318 @item @code{keyboard-layout} (default: @code{#f})
15319 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
15320 English (``qwerty'') for a 105-key PC keyboard.
15322 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
15323 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
15324 information on how to specify the keyboard layout.
15326 @item @code{extra-config} (default: @code{'()})
15327 This is a list of strings or objects appended to the configuration file. It
15328 is used to pass extra text to be added verbatim to the configuration file.
15330 @item @code{server} (default: @code{xorg-server})
15331 This is the package providing the Xorg server.
15333 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
15334 This is the list of command-line arguments to pass to the X server. The
15335 default is @code{-nolisten tcp}.
15339 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
15340 [@var{login-manager-service-type}]
15341 Tell the log-in manager (of type @var{login-manager-service-type}) to use
15342 @var{config}, an @code{<xorg-configuration>} record.
15344 Since the Xorg configuration is embedded in the log-in manager's
15345 configuration---e.g., @code{gdm-configuration}---this procedure provides a
15346 shorthand to set the Xorg configuration.
15349 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
15350 Return a @code{startx} script in which the modules, fonts, etc. specified
15351 in @var{config}, are available. The result should be used in place of
15354 Usually the X server is started by a login manager.
15358 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
15359 Add @var{package}, a package for a screen locker or screen saver whose
15360 command is @var{program}, to the set of setuid programs and add a PAM entry
15361 for it. For example:
15364 (screen-locker-service xlockmore "xlock")
15367 makes the good ol' XlockMore usable.
15371 @node Printing Services
15372 @subsection Printing Services
15374 @cindex printer support with CUPS
15375 The @code{(gnu services cups)} module provides a Guix service definition
15376 for the CUPS printing service. To add printer support to a Guix
15377 system, add a @code{cups-service} to the operating system definition:
15379 @deffn {Scheme Variable} cups-service-type
15380 The service type for the CUPS print server. Its value should be a valid
15381 CUPS configuration (see below). To use the default settings, simply
15384 (service cups-service-type)
15388 The CUPS configuration controls the basic things about your CUPS
15389 installation: what interfaces it listens on, what to do if a print job
15390 fails, how much logging to do, and so on. To actually add a printer,
15391 you have to visit the @url{http://localhost:631} URL, or use a tool such
15392 as GNOME's printer configuration services. By default, configuring a
15393 CUPS service will generate a self-signed certificate if needed, for
15394 secure connections to the print server.
15396 Suppose you want to enable the Web interface of CUPS and also add
15397 support for Epson printers @i{via} the @code{escpr} package and for HP
15398 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
15399 like this (you need to use the @code{(gnu packages cups)} module):
15402 (service cups-service-type
15403 (cups-configuration
15404 (web-interface? #t)
15406 (list cups-filters escpr hplip-minimal))))
15409 Note: If you wish to use the Qt5 based GUI which comes with the hplip
15410 package then it is suggested that you install the @code{hplip} package,
15411 either in your OS configuration file or as your user.
15413 The available configuration parameters follow. Each parameter
15414 definition is preceded by its type; for example, @samp{string-list foo}
15415 indicates that the @code{foo} parameter should be specified as a list of
15416 strings. There is also a way to specify the configuration as a string,
15417 if you have an old @code{cupsd.conf} file that you want to port over
15418 from some other system; see the end for more details.
15420 @c The following documentation was initially generated by
15421 @c (generate-documentation) in (gnu services cups). Manually maintained
15422 @c documentation is better, so we shouldn't hesitate to edit below as
15423 @c needed. However if the change you want to make to this documentation
15424 @c can be done in an automated way, it's probably easier to change
15425 @c (generate-documentation) than to make it below and have to deal with
15426 @c the churn as CUPS updates.
15429 Available @code{cups-configuration} fields are:
15431 @deftypevr {@code{cups-configuration} parameter} package cups
15435 @deftypevr {@code{cups-configuration} parameter} package-list extensions
15436 Drivers and other extensions to the CUPS package.
15439 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
15440 Configuration of where to write logs, what directories to use for print
15441 spools, and related privileged configuration parameters.
15443 Available @code{files-configuration} fields are:
15445 @deftypevr {@code{files-configuration} parameter} log-location access-log
15446 Defines the access log filename. Specifying a blank filename disables
15447 access log generation. The value @code{stderr} causes log entries to be
15448 sent to the standard error file when the scheduler is running in the
15449 foreground, or to the system log daemon when run in the background. The
15450 value @code{syslog} causes log entries to be sent to the system log
15451 daemon. The server name may be included in filenames using the string
15452 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
15454 Defaults to @samp{"/var/log/cups/access_log"}.
15457 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
15458 Where CUPS should cache data.
15460 Defaults to @samp{"/var/cache/cups"}.
15463 @deftypevr {@code{files-configuration} parameter} string config-file-perm
15464 Specifies the permissions for all configuration files that the scheduler
15467 Note that the permissions for the printers.conf file are currently
15468 masked to only allow access from the scheduler user (typically root).
15469 This is done because printer device URIs sometimes contain sensitive
15470 authentication information that should not be generally known on the
15471 system. There is no way to disable this security feature.
15473 Defaults to @samp{"0640"}.
15476 @deftypevr {@code{files-configuration} parameter} log-location error-log
15477 Defines the error log filename. Specifying a blank filename disables
15478 error log generation. The value @code{stderr} causes log entries to be
15479 sent to the standard error file when the scheduler is running in the
15480 foreground, or to the system log daemon when run in the background. The
15481 value @code{syslog} causes log entries to be sent to the system log
15482 daemon. The server name may be included in filenames using the string
15483 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
15485 Defaults to @samp{"/var/log/cups/error_log"}.
15488 @deftypevr {@code{files-configuration} parameter} string fatal-errors
15489 Specifies which errors are fatal, causing the scheduler to exit. The
15494 No errors are fatal.
15497 All of the errors below are fatal.
15500 Browsing initialization errors are fatal, for example failed connections
15501 to the DNS-SD daemon.
15504 Configuration file syntax errors are fatal.
15507 Listen or Port errors are fatal, except for IPv6 failures on the
15508 loopback or @code{any} addresses.
15511 Log file creation or write errors are fatal.
15514 Bad startup file permissions are fatal, for example shared TLS
15515 certificate and key files with world-read permissions.
15518 Defaults to @samp{"all -browse"}.
15521 @deftypevr {@code{files-configuration} parameter} boolean file-device?
15522 Specifies whether the file pseudo-device can be used for new printer
15523 queues. The URI @uref{file:///dev/null} is always allowed.
15525 Defaults to @samp{#f}.
15528 @deftypevr {@code{files-configuration} parameter} string group
15529 Specifies the group name or ID that will be used when executing external
15532 Defaults to @samp{"lp"}.
15535 @deftypevr {@code{files-configuration} parameter} string log-file-perm
15536 Specifies the permissions for all log files that the scheduler writes.
15538 Defaults to @samp{"0644"}.
15541 @deftypevr {@code{files-configuration} parameter} log-location page-log
15542 Defines the page log filename. Specifying a blank filename disables
15543 page log generation. The value @code{stderr} causes log entries to be
15544 sent to the standard error file when the scheduler is running in the
15545 foreground, or to the system log daemon when run in the background. The
15546 value @code{syslog} causes log entries to be sent to the system log
15547 daemon. The server name may be included in filenames using the string
15548 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
15550 Defaults to @samp{"/var/log/cups/page_log"}.
15553 @deftypevr {@code{files-configuration} parameter} string remote-root
15554 Specifies the username that is associated with unauthenticated accesses
15555 by clients claiming to be the root user. The default is @code{remroot}.
15557 Defaults to @samp{"remroot"}.
15560 @deftypevr {@code{files-configuration} parameter} file-name request-root
15561 Specifies the directory that contains print jobs and other HTTP request
15564 Defaults to @samp{"/var/spool/cups"}.
15567 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
15568 Specifies the level of security sandboxing that is applied to print
15569 filters, backends, and other child processes of the scheduler; either
15570 @code{relaxed} or @code{strict}. This directive is currently only
15571 used/supported on macOS.
15573 Defaults to @samp{strict}.
15576 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
15577 Specifies the location of TLS certificates and private keys. CUPS will
15578 look for public and private keys in this directory: @file{.crt} files
15579 for PEM-encoded certificates and corresponding @file{.key} files for
15580 PEM-encoded private keys.
15582 Defaults to @samp{"/etc/cups/ssl"}.
15585 @deftypevr {@code{files-configuration} parameter} file-name server-root
15586 Specifies the directory containing the server configuration files.
15588 Defaults to @samp{"/etc/cups"}.
15591 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
15592 Specifies whether the scheduler calls fsync(2) after writing
15593 configuration or state files.
15595 Defaults to @samp{#f}.
15598 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
15599 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
15602 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
15603 Specifies the directory where temporary files are stored.
15605 Defaults to @samp{"/var/spool/cups/tmp"}.
15608 @deftypevr {@code{files-configuration} parameter} string user
15609 Specifies the user name or ID that is used when running external
15612 Defaults to @samp{"lp"}.
15615 @deftypevr {@code{files-configuration} parameter} string set-env
15616 Set the specified environment variable to be passed to child processes.
15618 Defaults to @samp{"variable value"}.
15622 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
15623 Specifies the logging level for the AccessLog file. The @code{config}
15624 level logs when printers and classes are added, deleted, or modified and
15625 when configuration files are accessed or updated. The @code{actions}
15626 level logs when print jobs are submitted, held, released, modified, or
15627 canceled, and any of the conditions for @code{config}. The @code{all}
15628 level logs all requests.
15630 Defaults to @samp{actions}.
15633 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
15634 Specifies whether to purge job history data automatically when it is no
15635 longer required for quotas.
15637 Defaults to @samp{#f}.
15640 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
15641 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
15642 For example, @samp{"_cups" "_print"} will tell network clients that both
15643 CUPS sharing and IPP Everywhere are supported.
15645 Defaults to @samp{"_cups"}.
15648 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
15649 Specifies which protocols to use for local printer sharing.
15651 Defaults to @samp{dnssd}.
15654 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
15655 Specifies whether the CUPS web interface is advertised.
15657 Defaults to @samp{#f}.
15660 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
15661 Specifies whether shared printers are advertised.
15663 Defaults to @samp{#f}.
15666 @deftypevr {@code{cups-configuration} parameter} string classification
15667 Specifies the security classification of the server. Any valid banner
15668 name can be used, including @samp{"classified"}, @samp{"confidential"},
15669 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
15670 banner can be omitted to disable secure printing functions.
15672 Defaults to @samp{""}.
15675 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
15676 Specifies whether users may override the classification (cover page) of
15677 individual print jobs using the @code{job-sheets} option.
15679 Defaults to @samp{#f}.
15682 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
15683 Specifies the default type of authentication to use.
15685 Defaults to @samp{Basic}.
15688 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
15689 Specifies whether encryption will be used for authenticated requests.
15691 Defaults to @samp{Required}.
15694 @deftypevr {@code{cups-configuration} parameter} string default-language
15695 Specifies the default language to use for text and web content.
15697 Defaults to @samp{"en"}.
15700 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
15701 Specifies the default paper size for new print queues. @samp{"Auto"}
15702 uses a locale-specific default, while @samp{"None"} specifies there is
15703 no default paper size. Specific size names are typically
15704 @samp{"Letter"} or @samp{"A4"}.
15706 Defaults to @samp{"Auto"}.
15709 @deftypevr {@code{cups-configuration} parameter} string default-policy
15710 Specifies the default access policy to use.
15712 Defaults to @samp{"default"}.
15715 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
15716 Specifies whether local printers are shared by default.
15718 Defaults to @samp{#t}.
15721 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
15722 Specifies the delay for updating of configuration and state files, in
15723 seconds. A value of 0 causes the update to happen as soon as possible,
15724 typically within a few milliseconds.
15726 Defaults to @samp{30}.
15729 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
15730 Specifies what to do when an error occurs. Possible values are
15731 @code{abort-job}, which will discard the failed print job;
15732 @code{retry-job}, which will retry the job at a later time;
15733 @code{retry-current-job}, which retries the failed job immediately; and
15734 @code{stop-printer}, which stops the printer.
15736 Defaults to @samp{stop-printer}.
15739 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
15740 Specifies the maximum cost of filters that are run concurrently, which
15741 can be used to minimize disk, memory, and CPU resource problems. A
15742 limit of 0 disables filter limiting. An average print to a
15743 non-PostScript printer needs a filter limit of about 200. A PostScript
15744 printer needs about half that (100). Setting the limit below these
15745 thresholds will effectively limit the scheduler to printing a single job
15748 Defaults to @samp{0}.
15751 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
15752 Specifies the scheduling priority of filters that are run to print a
15753 job. The nice value ranges from 0, the highest priority, to 19, the
15756 Defaults to @samp{0}.
15759 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
15760 Specifies whether to do reverse lookups on connecting clients. The
15761 @code{double} setting causes @code{cupsd} to verify that the hostname
15762 resolved from the address matches one of the addresses returned for that
15763 hostname. Double lookups also prevent clients with unregistered
15764 addresses from connecting to your server. Only set this option to
15765 @code{#t} or @code{double} if absolutely required.
15767 Defaults to @samp{#f}.
15770 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
15771 Specifies the number of seconds to wait before killing the filters and
15772 backend associated with a canceled or held job.
15774 Defaults to @samp{30}.
15777 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
15778 Specifies the interval between retries of jobs in seconds. This is
15779 typically used for fax queues but can also be used with normal print
15780 queues whose error policy is @code{retry-job} or
15781 @code{retry-current-job}.
15783 Defaults to @samp{30}.
15786 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
15787 Specifies the number of retries that are done for jobs. This is
15788 typically used for fax queues but can also be used with normal print
15789 queues whose error policy is @code{retry-job} or
15790 @code{retry-current-job}.
15792 Defaults to @samp{5}.
15795 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
15796 Specifies whether to support HTTP keep-alive connections.
15798 Defaults to @samp{#t}.
15801 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
15802 Specifies how long an idle client connection remains open, in seconds.
15804 Defaults to @samp{30}.
15807 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
15808 Specifies the maximum size of print files, IPP requests, and HTML form
15809 data. A limit of 0 disables the limit check.
15811 Defaults to @samp{0}.
15814 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
15815 Listens on the specified interfaces for connections. Valid values are
15816 of the form @var{address}:@var{port}, where @var{address} is either an
15817 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
15818 indicate all addresses. Values can also be file names of local UNIX
15819 domain sockets. The Listen directive is similar to the Port directive
15820 but allows you to restrict access to specific interfaces or networks.
15823 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
15824 Specifies the number of pending connections that will be allowed. This
15825 normally only affects very busy servers that have reached the MaxClients
15826 limit, but can also be triggered by large numbers of simultaneous
15827 connections. When the limit is reached, the operating system will
15828 refuse additional connections until the scheduler can accept the pending
15831 Defaults to @samp{128}.
15834 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
15835 Specifies a set of additional access controls.
15837 Available @code{location-access-controls} fields are:
15839 @deftypevr {@code{location-access-controls} parameter} file-name path
15840 Specifies the URI path to which the access control applies.
15843 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
15844 Access controls for all access to this path, in the same format as the
15845 @code{access-controls} of @code{operation-access-control}.
15847 Defaults to @samp{()}.
15850 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
15851 Access controls for method-specific access to this path.
15853 Defaults to @samp{()}.
15855 Available @code{method-access-controls} fields are:
15857 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
15858 If @code{#t}, apply access controls to all methods except the listed
15859 methods. Otherwise apply to only the listed methods.
15861 Defaults to @samp{#f}.
15864 @deftypevr {@code{method-access-controls} parameter} method-list methods
15865 Methods to which this access control applies.
15867 Defaults to @samp{()}.
15870 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
15871 Access control directives, as a list of strings. Each string should be
15872 one directive, such as @samp{"Order allow,deny"}.
15874 Defaults to @samp{()}.
15879 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
15880 Specifies the number of debugging messages that are retained for logging
15881 if an error occurs in a print job. Debug messages are logged regardless
15882 of the LogLevel setting.
15884 Defaults to @samp{100}.
15887 @deftypevr {@code{cups-configuration} parameter} log-level log-level
15888 Specifies the level of logging for the ErrorLog file. The value
15889 @code{none} stops all logging while @code{debug2} logs everything.
15891 Defaults to @samp{info}.
15894 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
15895 Specifies the format of the date and time in the log files. The value
15896 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
15898 Defaults to @samp{standard}.
15901 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
15902 Specifies the maximum number of simultaneous clients that are allowed by
15905 Defaults to @samp{100}.
15908 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
15909 Specifies the maximum number of simultaneous clients that are allowed
15910 from a single address.
15912 Defaults to @samp{100}.
15915 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
15916 Specifies the maximum number of copies that a user can print of each
15919 Defaults to @samp{9999}.
15922 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
15923 Specifies the maximum time a job may remain in the @code{indefinite}
15924 hold state before it is canceled. A value of 0 disables cancellation of
15927 Defaults to @samp{0}.
15930 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
15931 Specifies the maximum number of simultaneous jobs that are allowed. Set
15932 to 0 to allow an unlimited number of jobs.
15934 Defaults to @samp{500}.
15937 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
15938 Specifies the maximum number of simultaneous jobs that are allowed per
15939 printer. A value of 0 allows up to MaxJobs jobs per printer.
15941 Defaults to @samp{0}.
15944 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
15945 Specifies the maximum number of simultaneous jobs that are allowed per
15946 user. A value of 0 allows up to MaxJobs jobs per user.
15948 Defaults to @samp{0}.
15951 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
15952 Specifies the maximum time a job may take to print before it is
15953 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
15955 Defaults to @samp{10800}.
15958 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
15959 Specifies the maximum size of the log files before they are rotated, in
15960 bytes. The value 0 disables log rotation.
15962 Defaults to @samp{1048576}.
15965 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
15966 Specifies the maximum amount of time to allow between files in a
15967 multiple file print job, in seconds.
15969 Defaults to @samp{300}.
15972 @deftypevr {@code{cups-configuration} parameter} string page-log-format
15973 Specifies the format of PageLog lines. Sequences beginning with percent
15974 (@samp{%}) characters are replaced with the corresponding information,
15975 while all other characters are copied literally. The following percent
15976 sequences are recognized:
15980 insert a single percent character
15983 insert the value of the specified IPP attribute
15986 insert the number of copies for the current page
15989 insert the current page number
15992 insert the current date and time in common log format
15998 insert the printer name
16001 insert the username
16004 A value of the empty string disables page logging. The string @code{%p
16005 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
16006 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
16009 Defaults to @samp{""}.
16012 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
16013 Passes the specified environment variable(s) to child processes; a list
16016 Defaults to @samp{()}.
16019 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
16020 Specifies named access control policies.
16022 Available @code{policy-configuration} fields are:
16024 @deftypevr {@code{policy-configuration} parameter} string name
16025 Name of the policy.
16028 @deftypevr {@code{policy-configuration} parameter} string job-private-access
16029 Specifies an access list for a job's private values. @code{@@ACL} maps
16030 to the printer's requesting-user-name-allowed or
16031 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
16032 owner. @code{@@SYSTEM} maps to the groups listed for the
16033 @code{system-group} field of the @code{files-config} configuration,
16034 which is reified into the @code{cups-files.conf(5)} file. Other
16035 possible elements of the access list include specific user names, and
16036 @code{@@@var{group}} to indicate members of a specific group. The
16037 access list may also be simply @code{all} or @code{default}.
16039 Defaults to @samp{"@@OWNER @@SYSTEM"}.
16042 @deftypevr {@code{policy-configuration} parameter} string job-private-values
16043 Specifies the list of job values to make private, or @code{all},
16044 @code{default}, or @code{none}.
16046 Defaults to @samp{"job-name job-originating-host-name
16047 job-originating-user-name phone"}.
16050 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
16051 Specifies an access list for a subscription's private values.
16052 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
16053 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
16054 owner. @code{@@SYSTEM} maps to the groups listed for the
16055 @code{system-group} field of the @code{files-config} configuration,
16056 which is reified into the @code{cups-files.conf(5)} file. Other
16057 possible elements of the access list include specific user names, and
16058 @code{@@@var{group}} to indicate members of a specific group. The
16059 access list may also be simply @code{all} or @code{default}.
16061 Defaults to @samp{"@@OWNER @@SYSTEM"}.
16064 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
16065 Specifies the list of job values to make private, or @code{all},
16066 @code{default}, or @code{none}.
16068 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
16069 notify-subscriber-user-name notify-user-data"}.
16072 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
16073 Access control by IPP operation.
16075 Defaults to @samp{()}.
16079 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
16080 Specifies whether job files (documents) are preserved after a job is
16081 printed. If a numeric value is specified, job files are preserved for
16082 the indicated number of seconds after printing. Otherwise a boolean
16083 value applies indefinitely.
16085 Defaults to @samp{86400}.
16088 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
16089 Specifies whether the job history is preserved after a job is printed.
16090 If a numeric value is specified, the job history is preserved for the
16091 indicated number of seconds after printing. If @code{#t}, the job
16092 history is preserved until the MaxJobs limit is reached.
16094 Defaults to @samp{#t}.
16097 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
16098 Specifies the amount of time to wait for job completion before
16099 restarting the scheduler.
16101 Defaults to @samp{30}.
16104 @deftypevr {@code{cups-configuration} parameter} string rip-cache
16105 Specifies the maximum amount of memory to use when converting documents
16106 into bitmaps for a printer.
16108 Defaults to @samp{"128m"}.
16111 @deftypevr {@code{cups-configuration} parameter} string server-admin
16112 Specifies the email address of the server administrator.
16114 Defaults to @samp{"root@@localhost.localdomain"}.
16117 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
16118 The ServerAlias directive is used for HTTP Host header validation when
16119 clients connect to the scheduler from external interfaces. Using the
16120 special name @code{*} can expose your system to known browser-based DNS
16121 rebinding attacks, even when accessing sites through a firewall. If the
16122 auto-discovery of alternate names does not work, we recommend listing
16123 each alternate name with a ServerAlias directive instead of using
16126 Defaults to @samp{*}.
16129 @deftypevr {@code{cups-configuration} parameter} string server-name
16130 Specifies the fully-qualified host name of the server.
16132 Defaults to @samp{"localhost"}.
16135 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
16136 Specifies what information is included in the Server header of HTTP
16137 responses. @code{None} disables the Server header. @code{ProductOnly}
16138 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
16139 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
16140 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
16141 the output of the @code{uname} command. @code{Full} reports @code{CUPS
16142 2.0.0 (@var{uname}) IPP/2.0}.
16144 Defaults to @samp{Minimal}.
16147 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
16148 Listens on the specified interfaces for encrypted connections. Valid
16149 values are of the form @var{address}:@var{port}, where @var{address} is
16150 either an IPv6 address enclosed in brackets, an IPv4 address, or
16151 @code{*} to indicate all addresses.
16153 Defaults to @samp{()}.
16156 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
16157 Sets encryption options. By default, CUPS only supports encryption
16158 using TLS v1.0 or higher using known secure cipher suites. Security is
16159 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
16160 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
16161 suites, which are required for some older clients. The @code{AllowSSL3} option
16162 enables SSL v3.0, which is required for some older clients that do not support
16163 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
16164 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
16165 protocol version to TLS v1.1.
16167 Defaults to @samp{()}.
16170 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
16171 Specifies whether the scheduler requires clients to strictly adhere to
16172 the IPP specifications.
16174 Defaults to @samp{#f}.
16177 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
16178 Specifies the HTTP request timeout, in seconds.
16180 Defaults to @samp{300}.
16184 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
16185 Specifies whether the web interface is enabled.
16187 Defaults to @samp{#f}.
16190 At this point you're probably thinking ``oh dear, Guix manual, I like
16191 you but you can stop already with the configuration options''. Indeed.
16192 However, one more point: it could be that you have an existing
16193 @code{cupsd.conf} that you want to use. In that case, you can pass an
16194 @code{opaque-cups-configuration} as the configuration of a
16195 @code{cups-service-type}.
16197 Available @code{opaque-cups-configuration} fields are:
16199 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
16203 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
16204 The contents of the @code{cupsd.conf}, as a string.
16207 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
16208 The contents of the @code{cups-files.conf} file, as a string.
16211 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
16212 strings of the same name, you could instantiate a CUPS service like
16216 (service cups-service-type
16217 (opaque-cups-configuration
16218 (cupsd.conf cupsd.conf)
16219 (cups-files.conf cups-files.conf)))
16223 @node Desktop Services
16224 @subsection Desktop Services
16226 The @code{(gnu services desktop)} module provides services that are
16227 usually useful in the context of a ``desktop'' setup---that is, on a
16228 machine running a graphical display server, possibly with graphical user
16229 interfaces, etc. It also defines services that provide specific desktop
16230 environments like GNOME, Xfce or MATE.
16232 To simplify things, the module defines a variable containing the set of
16233 services that users typically expect on a machine with a graphical
16234 environment and networking:
16236 @defvr {Scheme Variable} %desktop-services
16237 This is a list of services that builds upon @code{%base-services} and
16238 adds or adjusts services for a typical ``desktop'' setup.
16240 In particular, it adds a graphical login manager (@pxref{X Window,
16241 @code{gdm-service-type}}), screen lockers, a network management tool
16242 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
16243 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
16244 energy and color management services, the @code{elogind} login and seat
16245 manager, the Polkit privilege service, the GeoClue location service, the
16246 AccountsService daemon that allows authorized users change system passwords,
16247 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
16248 name service switch service configured to be able to use @code{nss-mdns}
16249 (@pxref{Name Service Switch, mDNS}).
16252 The @code{%desktop-services} variable can be used as the @code{services}
16253 field of an @code{operating-system} declaration (@pxref{operating-system
16254 Reference, @code{services}}).
16256 Additionally, the @code{gnome-desktop-service-type},
16257 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
16258 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
16259 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
16260 services like the backlight adjustment helpers and the power management
16261 utilities are added to the system, extending @code{polkit} and @code{dbus}
16262 appropriately, allowing GNOME to operate with elevated privileges on a
16263 limited number of special-purpose system interfaces. Additionally,
16264 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
16265 metapackage to the system profile. Likewise, adding the Xfce service
16266 not only adds the @code{xfce} metapackage to the system profile, but it
16267 also gives the Thunar file manager the ability to open a ``root-mode''
16268 file management window, if the user authenticates using the
16269 administrator's password via the standard polkit graphical interface.
16270 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
16271 appropriately, allowing MATE to operate with elevated privileges on a
16272 limited number of special-purpose system interfaces. Additionally,
16273 adding a service of type @code{mate-desktop-service-type} adds the MATE
16274 metapackage to the system profile. ``Adding Enlightenment'' means that
16275 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
16276 are set as setuid, allowing Enlightenment's screen locker and other
16277 functionality to work as expected.
16279 The desktop environments in Guix use the Xorg display server by
16280 default. If you'd like to use the newer display server protocol
16281 called Wayland, you need to use the @code{sddm-service} instead of
16282 GDM as the graphical login manager. You should then
16283 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
16284 also try starting GNOME on Wayland manually from a TTY with the
16285 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
16286 gnome-session``. Currently only GNOME has support for Wayland.
16288 @defvr {Scheme Variable} gnome-desktop-service-type
16289 This is the type of the service that adds the @uref{https://www.gnome.org,
16290 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
16291 object (see below).
16293 This service adds the @code{gnome} package to the system profile, and extends
16294 polkit with the actions from @code{gnome-settings-daemon}.
16297 @deftp {Data Type} gnome-desktop-configuration
16298 Configuration record for the GNOME desktop environment.
16301 @item @code{gnome} (default: @code{gnome})
16302 The GNOME package to use.
16306 @defvr {Scheme Variable} xfce-desktop-service-type
16307 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
16308 desktop environment. Its value is an @code{xfce-desktop-configuration} object
16311 This service adds the @code{xfce} package to the system profile, and
16312 extends polkit with the ability for @code{thunar} to manipulate the file
16313 system as root from within a user session, after the user has authenticated
16314 with the administrator's password.
16317 @deftp {Data Type} xfce-desktop-configuration
16318 Configuration record for the Xfce desktop environment.
16321 @item @code{xfce} (default: @code{xfce})
16322 The Xfce package to use.
16326 @deffn {Scheme Variable} mate-desktop-service-type
16327 This is the type of the service that runs the @uref{https://mate-desktop.org/,
16328 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
16329 object (see below).
16331 This service adds the @code{mate} package to the system
16332 profile, and extends polkit with the actions from
16333 @code{mate-settings-daemon}.
16336 @deftp {Data Type} mate-desktop-configuration
16337 Configuration record for the MATE desktop environment.
16340 @item @code{mate} (default: @code{mate})
16341 The MATE package to use.
16345 @deffn {Scheme Variable} enlightenment-desktop-service-type
16346 Return a service that adds the @code{enlightenment} package to the system
16347 profile, and extends dbus with actions from @code{efl}.
16350 @deftp {Data Type} enlightenment-desktop-service-configuration
16352 @item @code{enlightenment} (default: @code{enlightenment})
16353 The enlightenment package to use.
16357 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
16358 the default @code{%desktop-services} variable doesn't include any of
16359 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
16360 @code{%desktop-services} in the @code{services} field of your
16361 @code{operating-system}:
16364 (use-modules (gnu))
16365 (use-service-modules desktop)
16368 ;; cons* adds items to the list given as its last argument.
16369 (services (cons* (service gnome-desktop-service-type)
16370 (service xfce-desktop-service)
16371 %desktop-services))
16375 These desktop environments will then be available as options in the
16376 graphical login window.
16378 The actual service definitions included in @code{%desktop-services} and
16379 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
16380 are described below.
16382 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
16383 Return a service that runs the ``system bus'', using @var{dbus}, with
16384 support for @var{services}.
16386 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
16387 facility. Its system bus is used to allow system services to communicate
16388 and to be notified of system-wide events.
16390 @var{services} must be a list of packages that provide an
16391 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
16392 and policy files. For example, to allow avahi-daemon to use the system bus,
16393 @var{services} must be equal to @code{(list avahi)}.
16396 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
16397 Return a service that runs the @code{elogind} login and
16398 seat management daemon. @uref{https://github.com/elogind/elogind,
16399 Elogind} exposes a D-Bus interface that can be used to know which users
16400 are logged in, know what kind of sessions they have open, suspend the
16401 system, inhibit system suspend, reboot the system, and other tasks.
16403 Elogind handles most system-level power events for a computer, for
16404 example suspending the system when a lid is closed, or shutting it down
16405 when the power button is pressed.
16407 The @var{config} keyword argument specifies the configuration for
16408 elogind, and should be the result of an @code{(elogind-configuration
16409 (@var{parameter} @var{value})...)} invocation. Available parameters and
16410 their default values are:
16413 @item kill-user-processes?
16415 @item kill-only-users
16417 @item kill-exclude-users
16419 @item inhibit-delay-max-seconds
16421 @item handle-power-key
16423 @item handle-suspend-key
16425 @item handle-hibernate-key
16427 @item handle-lid-switch
16429 @item handle-lid-switch-docked
16431 @item power-key-ignore-inhibited?
16433 @item suspend-key-ignore-inhibited?
16435 @item hibernate-key-ignore-inhibited?
16437 @item lid-switch-ignore-inhibited?
16439 @item holdoff-timeout-seconds
16443 @item idle-action-seconds
16445 @item runtime-directory-size-percent
16447 @item runtime-directory-size
16451 @item suspend-state
16452 @code{("mem" "standby" "freeze")}
16455 @item hibernate-state
16457 @item hibernate-mode
16458 @code{("platform" "shutdown")}
16459 @item hybrid-sleep-state
16461 @item hybrid-sleep-mode
16462 @code{("suspend" "platform" "shutdown")}
16466 @deffn {Scheme Procedure} accountsservice-service @
16467 [#:accountsservice @var{accountsservice}]
16468 Return a service that runs AccountsService, a system service that can
16469 list available accounts, change their passwords, and so on.
16470 AccountsService integrates with PolicyKit to enable unprivileged users
16471 to acquire the capability to modify their system configuration.
16472 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
16473 accountsservice web site} for more information.
16475 The @var{accountsservice} keyword argument is the @code{accountsservice}
16476 package to expose as a service.
16479 @deffn {Scheme Procedure} polkit-service @
16480 [#:polkit @var{polkit}]
16481 Return a service that runs the
16482 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
16483 management service}, which allows system administrators to grant access to
16484 privileged operations in a structured way. By querying the Polkit service, a
16485 privileged system component can know when it should grant additional
16486 capabilities to ordinary users. For example, an ordinary user can be granted
16487 the capability to suspend the system if the user is logged in locally.
16490 @defvr {Scheme Variable} polkit-wheel-service
16491 Service that adds the @code{wheel} group as admins to the Polkit
16492 service. This makes it so that users in the @code{wheel} group are queried
16493 for their own passwords when performing administrative actions instead of
16494 @code{root}'s, similar to the behaviour used by @code{sudo}.
16497 @defvr {Scheme Variable} upower-service-type
16498 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
16499 system-wide monitor for power consumption and battery levels, with the given
16500 configuration settings.
16502 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
16503 notably used by GNOME.
16506 @deftp {Data Type} upower-configuration
16507 Data type representation the configuration for UPower.
16511 @item @code{upower} (default: @var{upower})
16512 Package to use for @code{upower}.
16514 @item @code{watts-up-pro?} (default: @code{#f})
16515 Enable the Watts Up Pro device.
16517 @item @code{poll-batteries?} (default: @code{#t})
16518 Enable polling the kernel for battery level changes.
16520 @item @code{ignore-lid?} (default: @code{#f})
16521 Ignore the lid state, this can be useful if it's incorrect on a device.
16523 @item @code{use-percentage-for-policy?} (default: @code{#f})
16524 Whether battery percentage based policy should be used. The default is to use
16525 the time left, change to @code{#t} to use the percentage.
16527 @item @code{percentage-low} (default: @code{10})
16528 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16529 at which the battery is considered low.
16531 @item @code{percentage-critical} (default: @code{3})
16532 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16533 at which the battery is considered critical.
16535 @item @code{percentage-action} (default: @code{2})
16536 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16537 at which action will be taken.
16539 @item @code{time-low} (default: @code{1200})
16540 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16541 seconds at which the battery is considered low.
16543 @item @code{time-critical} (default: @code{300})
16544 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16545 seconds at which the battery is considered critical.
16547 @item @code{time-action} (default: @code{120})
16548 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16549 seconds at which action will be taken.
16551 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
16552 The action taken when @code{percentage-action} or @code{time-action} is
16553 reached (depending on the configuration of @code{use-percentage-for-policy?}).
16555 Possible values are:
16565 @code{'hybrid-sleep}.
16571 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
16572 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
16573 UDisks}, a @dfn{disk management} daemon that provides user interfaces
16574 with notifications and ways to mount/unmount disks. Programs that talk
16575 to UDisks include the @command{udisksctl} command, part of UDisks, and
16576 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
16577 it will only be able to use the file-system utilities installed in the
16578 system profile. For example if you want to be able to mount NTFS
16579 file-systems in read and write fashion, you'll need to have
16580 @code{ntfs-3g} installed system-wide.
16583 @deffn {Scheme Variable} colord-service-type
16584 This is the type of the service that runs @command{colord}, a system
16585 service with a D-Bus
16586 interface to manage the color profiles of input and output devices such as
16587 screens and scanners. It is notably used by the GNOME Color Manager graphical
16588 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
16589 site} for more information.
16592 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
16593 Return a configuration allowing an application to access GeoClue
16594 location data. @var{name} is the Desktop ID of the application, without
16595 the @code{.desktop} part. If @var{allowed?} is true, the application
16596 will have access to location information by default. The boolean
16597 @var{system?} value indicates whether an application is a system component
16598 or not. Finally @var{users} is a list of UIDs of all users for which
16599 this application is allowed location info access. An empty users list
16600 means that all users are allowed.
16603 @cindex scanner access
16604 @deffn {Scheme Procedure} sane-service-type
16605 This service provides access to scanners @i{via}
16606 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
16610 @defvr {Scheme Variable} %standard-geoclue-applications
16611 The standard list of well-known GeoClue application configurations,
16612 granting authority to the GNOME date-and-time utility to ask for the
16613 current location in order to set the time zone, and allowing the
16614 IceCat and Epiphany web browsers to request location information.
16615 IceCat and Epiphany both query the user before allowing a web page to
16616 know the user's location.
16619 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
16620 [#:whitelist '()] @
16621 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
16622 [#:submit-data? #f]
16623 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
16624 [#:submission-nick "geoclue"] @
16625 [#:applications %standard-geoclue-applications]
16626 Return a service that runs the GeoClue location service. This service
16627 provides a D-Bus interface to allow applications to request access to a
16628 user's physical location, and optionally to add information to online
16629 location databases. See
16630 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
16631 web site} for more information.
16634 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
16635 [@w{#:auto-enable? #f}]
16636 Return a service that runs the @command{bluetoothd} daemon, which
16637 manages all the Bluetooth devices and provides a number of D-Bus
16638 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
16639 powered automatically at boot, which can be useful when using a
16640 bluetooth keyboard or mouse.
16642 Users need to be in the @code{lp} group to access the D-Bus service.
16645 @defvr {Scheme Variable} gnome-keyring-service-type
16646 This is the type of the service that adds the
16647 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
16648 value is a @code{gnome-keyring-configuration} object (see below).
16650 This service adds the @code{gnome-keyring} package to the system profile
16651 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
16652 a user's login keyring when they log in or setting its password with passwd.
16655 @deftp {Data Type} gnome-keyring-configuration
16656 Configuration record for the GNOME Keyring service.
16659 @item @code{keyring} (default: @code{gnome-keyring})
16660 The GNOME keyring package to use.
16662 @item @code{pam-services}
16663 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
16664 services to extend, where @var{service} is the name of an existing
16665 service to extend and @var{kind} is one of @code{login} or
16668 If @code{login} is given, it adds an optional
16669 @code{pam_gnome_keyring.so} to the auth block without arguments and to
16670 the session block with @code{auto_start}. If @code{passwd} is given, it
16671 adds an optional @code{pam_gnome_keyring.so} to the password block
16674 By default, this field contains ``gdm-password'' with the value @code{login}
16675 and ``passwd'' is with the value @code{passwd}.
16680 @node Sound Services
16681 @subsection Sound Services
16683 @cindex sound support
16685 @cindex PulseAudio, sound support
16687 The @code{(gnu services sound)} module provides a service to configure the
16688 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
16689 preferred ALSA output driver.
16691 @deffn {Scheme Variable} alsa-service-type
16692 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
16693 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
16694 configuration file. The value for this type is a @command{alsa-configuration}
16695 record as in this example:
16698 (service alsa-service-type)
16701 See below for details about @code{alsa-configuration}.
16704 @deftp {Data Type} alsa-configuration
16705 Data type representing the configuration for @code{alsa-service}.
16708 @item @code{alsa-plugins} (default: @var{alsa-plugins})
16709 @code{alsa-plugins} package to use.
16711 @item @code{pulseaudio?} (default: @var{#t})
16712 Whether ALSA applications should transparently be made to use the
16713 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
16715 Using PulseAudio allows you to run several sound-producing applications
16716 at the same time and to individual control them @i{via}
16717 @command{pavucontrol}, among other things.
16719 @item @code{extra-options} (default: @var{""})
16720 String to append to the @file{/etc/asound.conf} file.
16725 Individual users who want to override the system configuration of ALSA can do
16726 it with the @file{~/.asoundrc} file:
16729 # In guix, we have to specify the absolute path for plugins.
16731 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
16734 # Routing ALSA to jack:
16735 # <http://jackaudio.org/faq/routing_alsa.html>.
16739 0 system:playback_1
16740 1 system:playback_2
16757 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
16760 @deffn {Scheme Variable} pulseaudio-service-type
16761 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
16762 sound server. It exists to allow system overrides of the default settings
16763 via @code{pulseaudio-configuration}, see below.
16766 This service overrides per-user configuration files. If you want
16767 PulseAudio to honor configuraton files in @file{~/.config/pulse} you
16768 have to unset the environment variables @env{PULSE_CONFIG} and
16769 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
16773 This service on its own does not ensure, that the @code{pulseaudio} package
16774 exists on your machine. It merely adds configuration files for it, as
16775 detailed below. In the (admittedly unlikely) case, that you find yourself
16776 without a @code{pulseaudio} package, consider enabling it through the
16777 @code{alsa-service-type} above.
16781 @deftp {Data Type} pulseaudio-configuration
16782 Data type representing the configuration for @code{pulseaudio-service}.
16785 @item @var{client-conf} (default: @code{'()})
16786 List of settings to set in @file{client.conf}.
16787 Accepts a list of strings or a symbol-value pairs. A string will be
16788 inserted as-is with a newline added. A pair will be formatted as
16789 ``key = value'', again with a newline added.
16791 @item @var{daemon-conf} (default: @code{'((flat-volumes . no))})
16792 List of settings to set in @file{daemon.conf}, formatted just like
16795 @item @var{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
16796 Script file to use as as @file{default.pa}.
16798 @item @var{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
16799 Script file to use as as @file{system.pa}.
16803 @deffn {Scheme Variable} ladspa-service-type
16804 This service sets the @var{LADSPA_PATH} variable, so that programs, which
16805 respect it, e.g. PulseAudio, can load LADSPA plugins.
16807 The following example will setup the service to enable modules from the
16808 @code{swh-plugins} package:
16811 (service ladspa-service-type
16812 (ladspa-configuration (plugins (list swh-plugins))))
16815 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
16820 @node Database Services
16821 @subsection Database Services
16825 The @code{(gnu services databases)} module provides the following services.
16827 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
16828 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
16829 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
16830 Return a service that runs @var{postgresql}, the PostgreSQL database
16833 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
16834 creates a database cluster with @var{locale} as the default
16835 locale, stored in @var{data-directory}. It then listens on @var{port}.
16837 @cindex postgresql extension-packages
16838 Additional extensions are loaded from packages listed in
16839 @var{extension-packages}. Extensions are available at runtime. For instance,
16840 to create a geographic database using the @code{postgis} extension, a user can
16841 configure the postgresql-service as in this example:
16845 (use-package-modules databases geo)
16849 ;; postgresql is required to run `psql' but postgis is not required for
16850 ;; proper operation.
16851 (packages (cons* postgresql %base-packages))
16854 (postgresql-service #:extension-packages (list postgis))
16858 Then the extension becomes visible and you can initialise an empty geographic
16859 database in this way:
16863 > create database postgistest;
16864 > \connect postgistest;
16865 > create extension postgis;
16866 > create extension postgis_topology;
16869 There is no need to add this field for contrib extensions such as hstore or
16870 dblink as they are already loadable by postgresql. This field is only
16871 required to add extensions provided by other packages.
16874 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
16875 Return a service that runs @command{mysqld}, the MySQL or MariaDB
16878 The optional @var{config} argument specifies the configuration for
16879 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
16882 @deftp {Data Type} mysql-configuration
16883 Data type representing the configuration of @var{mysql-service}.
16886 @item @code{mysql} (default: @var{mariadb})
16887 Package object of the MySQL database server, can be either @var{mariadb}
16890 For MySQL, a temporary root password will be displayed at activation time.
16891 For MariaDB, the root password is empty.
16893 @item @code{port} (default: @code{3306})
16894 TCP port on which the database server listens for incoming connections.
16898 @defvr {Scheme Variable} memcached-service-type
16899 This is the service type for the @uref{https://memcached.org/,
16900 Memcached} service, which provides a distributed in memory cache. The
16901 value for the service type is a @code{memcached-configuration} object.
16905 (service memcached-service-type)
16908 @deftp {Data Type} memcached-configuration
16909 Data type representing the configuration of memcached.
16912 @item @code{memcached} (default: @code{memcached})
16913 The Memcached package to use.
16915 @item @code{interfaces} (default: @code{'("0.0.0.0")})
16916 Network interfaces on which to listen.
16918 @item @code{tcp-port} (default: @code{11211})
16919 Port on which to accept connections on,
16921 @item @code{udp-port} (default: @code{11211})
16922 Port on which to accept UDP connections on, a value of 0 will disable
16923 listening on a UDP socket.
16925 @item @code{additional-options} (default: @code{'()})
16926 Additional command line options to pass to @code{memcached}.
16930 @defvr {Scheme Variable} mongodb-service-type
16931 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
16932 The value for the service type is a @code{mongodb-configuration} object.
16936 (service mongodb-service-type)
16939 @deftp {Data Type} mongodb-configuration
16940 Data type representing the configuration of mongodb.
16943 @item @code{mongodb} (default: @code{mongodb})
16944 The MongoDB package to use.
16946 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
16947 The configuration file for MongoDB.
16949 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
16950 This value is used to create the directory, so that it exists and is
16951 owned by the mongodb user. It should match the data-directory which
16952 MongoDB is configured to use through the configuration file.
16956 @defvr {Scheme Variable} redis-service-type
16957 This is the service type for the @uref{https://redis.io/, Redis}
16958 key/value store, whose value is a @code{redis-configuration} object.
16961 @deftp {Data Type} redis-configuration
16962 Data type representing the configuration of redis.
16965 @item @code{redis} (default: @code{redis})
16966 The Redis package to use.
16968 @item @code{bind} (default: @code{"127.0.0.1"})
16969 Network interface on which to listen.
16971 @item @code{port} (default: @code{6379})
16972 Port on which to accept connections on, a value of 0 will disable
16973 listening on a TCP socket.
16975 @item @code{working-directory} (default: @code{"/var/lib/redis"})
16976 Directory in which to store the database and related files.
16980 @node Mail Services
16981 @subsection Mail Services
16985 The @code{(gnu services mail)} module provides Guix service definitions
16986 for email services: IMAP, POP3, and LMTP servers, as well as mail
16987 transport agents (MTAs). Lots of acronyms! These services are detailed
16988 in the subsections below.
16990 @subsubheading Dovecot Service
16992 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
16993 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
16996 By default, Dovecot does not need much configuration; the default
16997 configuration object created by @code{(dovecot-configuration)} will
16998 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
16999 certificate will be generated for TLS-protected connections, though
17000 Dovecot will also listen on cleartext ports by default. There are a
17001 number of options, though, which mail administrators might need to change,
17002 and as is the case with other services, Guix allows the system
17003 administrator to specify these parameters via a uniform Scheme interface.
17005 For example, to specify that mail is located at @code{maildir~/.mail},
17006 one would instantiate the Dovecot service like this:
17009 (dovecot-service #:config
17010 (dovecot-configuration
17011 (mail-location "maildir:~/.mail")))
17014 The available configuration parameters follow. Each parameter
17015 definition is preceded by its type; for example, @samp{string-list foo}
17016 indicates that the @code{foo} parameter should be specified as a list of
17017 strings. There is also a way to specify the configuration as a string,
17018 if you have an old @code{dovecot.conf} file that you want to port over
17019 from some other system; see the end for more details.
17021 @c The following documentation was initially generated by
17022 @c (generate-documentation) in (gnu services mail). Manually maintained
17023 @c documentation is better, so we shouldn't hesitate to edit below as
17024 @c needed. However if the change you want to make to this documentation
17025 @c can be done in an automated way, it's probably easier to change
17026 @c (generate-documentation) than to make it below and have to deal with
17027 @c the churn as dovecot updates.
17029 Available @code{dovecot-configuration} fields are:
17031 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
17032 The dovecot package.
17035 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
17036 A list of IPs or hosts where to listen for connections. @samp{*}
17037 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
17038 interfaces. If you want to specify non-default ports or anything more
17039 complex, customize the address and port fields of the
17040 @samp{inet-listener} of the specific services you are interested in.
17043 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
17044 List of protocols we want to serve. Available protocols include
17045 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
17047 Available @code{protocol-configuration} fields are:
17049 @deftypevr {@code{protocol-configuration} parameter} string name
17050 The name of the protocol.
17053 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
17054 UNIX socket path to the master authentication server to find users.
17055 This is used by imap (for shared users) and lda.
17056 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17059 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
17060 Space separated list of plugins to load.
17063 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
17064 Maximum number of IMAP connections allowed for a user from each IP
17065 address. NOTE: The username is compared case-sensitively.
17066 Defaults to @samp{10}.
17071 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
17072 List of services to enable. Available services include @samp{imap},
17073 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
17076 Available @code{service-configuration} fields are:
17078 @deftypevr {@code{service-configuration} parameter} string kind
17079 The service kind. Valid values include @code{director},
17080 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
17081 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
17082 @code{tcpwrap}, @code{quota-warning}, or anything else.
17085 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
17086 Listeners for the service. A listener is either a
17087 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
17088 an @code{inet-listener-configuration}.
17089 Defaults to @samp{()}.
17091 Available @code{unix-listener-configuration} fields are:
17093 @deftypevr {@code{unix-listener-configuration} parameter} string path
17094 Path to the file, relative to @code{base-dir} field. This is also used as
17098 @deftypevr {@code{unix-listener-configuration} parameter} string mode
17099 The access mode for the socket.
17100 Defaults to @samp{"0600"}.
17103 @deftypevr {@code{unix-listener-configuration} parameter} string user
17104 The user to own the socket.
17105 Defaults to @samp{""}.
17108 @deftypevr {@code{unix-listener-configuration} parameter} string group
17109 The group to own the socket.
17110 Defaults to @samp{""}.
17114 Available @code{fifo-listener-configuration} fields are:
17116 @deftypevr {@code{fifo-listener-configuration} parameter} string path
17117 Path to the file, relative to @code{base-dir} field. This is also used as
17121 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
17122 The access mode for the socket.
17123 Defaults to @samp{"0600"}.
17126 @deftypevr {@code{fifo-listener-configuration} parameter} string user
17127 The user to own the socket.
17128 Defaults to @samp{""}.
17131 @deftypevr {@code{fifo-listener-configuration} parameter} string group
17132 The group to own the socket.
17133 Defaults to @samp{""}.
17137 Available @code{inet-listener-configuration} fields are:
17139 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
17140 The protocol to listen for.
17143 @deftypevr {@code{inet-listener-configuration} parameter} string address
17144 The address on which to listen, or empty for all addresses.
17145 Defaults to @samp{""}.
17148 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
17149 The port on which to listen.
17152 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
17153 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
17155 Defaults to @samp{#t}.
17160 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
17161 Maximum number of simultaneous client connections per process. Once
17162 this number of connections is received, the next incoming connection
17163 will prompt Dovecot to spawn another process. If set to 0,
17164 @code{default-client-limit} is used instead.
17166 Defaults to @samp{0}.
17170 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
17171 Number of connections to handle before starting a new process.
17172 Typically the only useful values are 0 (unlimited) or 1. 1 is more
17173 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
17174 Defaults to @samp{1}.
17178 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
17179 Maximum number of processes that can exist for this service. If set to
17180 0, @code{default-process-limit} is used instead.
17182 Defaults to @samp{0}.
17186 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
17187 Number of processes to always keep waiting for more connections.
17188 Defaults to @samp{0}.
17191 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
17192 If you set @samp{service-count 0}, you probably need to grow
17194 Defaults to @samp{256000000}.
17199 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
17200 Dict configuration, as created by the @code{dict-configuration}
17203 Available @code{dict-configuration} fields are:
17205 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
17206 A list of key-value pairs that this dict should hold.
17207 Defaults to @samp{()}.
17212 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
17213 A list of passdb configurations, each one created by the
17214 @code{passdb-configuration} constructor.
17216 Available @code{passdb-configuration} fields are:
17218 @deftypevr {@code{passdb-configuration} parameter} string driver
17219 The driver that the passdb should use. Valid values include
17220 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
17222 Defaults to @samp{"pam"}.
17225 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
17226 Space separated list of arguments to the passdb driver.
17227 Defaults to @samp{""}.
17232 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
17233 List of userdb configurations, each one created by the
17234 @code{userdb-configuration} constructor.
17236 Available @code{userdb-configuration} fields are:
17238 @deftypevr {@code{userdb-configuration} parameter} string driver
17239 The driver that the userdb should use. Valid values include
17240 @samp{passwd} and @samp{static}.
17241 Defaults to @samp{"passwd"}.
17244 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
17245 Space separated list of arguments to the userdb driver.
17246 Defaults to @samp{""}.
17249 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
17250 Override fields from passwd.
17251 Defaults to @samp{()}.
17256 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
17257 Plug-in configuration, created by the @code{plugin-configuration}
17261 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
17262 List of namespaces. Each item in the list is created by the
17263 @code{namespace-configuration} constructor.
17265 Available @code{namespace-configuration} fields are:
17267 @deftypevr {@code{namespace-configuration} parameter} string name
17268 Name for this namespace.
17271 @deftypevr {@code{namespace-configuration} parameter} string type
17272 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
17273 Defaults to @samp{"private"}.
17276 @deftypevr {@code{namespace-configuration} parameter} string separator
17277 Hierarchy separator to use. You should use the same separator for
17278 all namespaces or some clients get confused. @samp{/} is usually a good
17279 one. The default however depends on the underlying mail storage
17281 Defaults to @samp{""}.
17284 @deftypevr {@code{namespace-configuration} parameter} string prefix
17285 Prefix required to access this namespace. This needs to be
17286 different for all namespaces. For example @samp{Public/}.
17287 Defaults to @samp{""}.
17290 @deftypevr {@code{namespace-configuration} parameter} string location
17291 Physical location of the mailbox. This is in the same format as
17292 mail_location, which is also the default for it.
17293 Defaults to @samp{""}.
17296 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
17297 There can be only one INBOX, and this setting defines which
17299 Defaults to @samp{#f}.
17302 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
17303 If namespace is hidden, it's not advertised to clients via NAMESPACE
17304 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
17305 useful when converting from another server with different namespaces
17306 which you want to deprecate but still keep working. For example you can
17307 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
17309 Defaults to @samp{#f}.
17312 @deftypevr {@code{namespace-configuration} parameter} boolean list?
17313 Show the mailboxes under this namespace with the LIST command. This
17314 makes the namespace visible for clients that do not support the NAMESPACE
17315 extension. The special @code{children} value lists child mailboxes, but
17316 hides the namespace prefix.
17317 Defaults to @samp{#t}.
17320 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
17321 Namespace handles its own subscriptions. If set to @code{#f}, the
17322 parent namespace handles them. The empty prefix should always have this
17324 Defaults to @samp{#t}.
17327 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
17328 List of predefined mailboxes in this namespace.
17329 Defaults to @samp{()}.
17331 Available @code{mailbox-configuration} fields are:
17333 @deftypevr {@code{mailbox-configuration} parameter} string name
17334 Name for this mailbox.
17337 @deftypevr {@code{mailbox-configuration} parameter} string auto
17338 @samp{create} will automatically create this mailbox.
17339 @samp{subscribe} will both create and subscribe to the mailbox.
17340 Defaults to @samp{"no"}.
17343 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
17344 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
17345 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
17346 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
17347 Defaults to @samp{()}.
17354 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
17355 Base directory where to store runtime data.
17356 Defaults to @samp{"/var/run/dovecot/"}.
17359 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
17360 Greeting message for clients.
17361 Defaults to @samp{"Dovecot ready."}.
17364 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
17365 List of trusted network ranges. Connections from these IPs are
17366 allowed to override their IP addresses and ports (for logging and for
17367 authentication checks). @samp{disable-plaintext-auth} is also ignored
17368 for these networks. Typically you would specify your IMAP proxy servers
17370 Defaults to @samp{()}.
17373 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
17374 List of login access check sockets (e.g.@: tcpwrap).
17375 Defaults to @samp{()}.
17378 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
17379 Show more verbose process titles (in ps). Currently shows user name
17380 and IP address. Useful for seeing who is actually using the IMAP
17381 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
17383 Defaults to @samp{#f}.
17386 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
17387 Should all processes be killed when Dovecot master process shuts down.
17388 Setting this to @code{#f} means that Dovecot can be upgraded without
17389 forcing existing client connections to close (although that could also
17390 be a problem if the upgrade is e.g.@: due to a security fix).
17391 Defaults to @samp{#t}.
17394 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
17395 If non-zero, run mail commands via this many connections to doveadm
17396 server, instead of running them directly in the same process.
17397 Defaults to @samp{0}.
17400 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
17401 UNIX socket or host:port used for connecting to doveadm server.
17402 Defaults to @samp{"doveadm-server"}.
17405 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
17406 List of environment variables that are preserved on Dovecot startup
17407 and passed down to all of its child processes. You can also give
17408 key=value pairs to always set specific settings.
17411 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
17412 Disable LOGIN command and all other plaintext authentications unless
17413 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
17414 matches the local IP (i.e.@: you're connecting from the same computer),
17415 the connection is considered secure and plaintext authentication is
17416 allowed. See also ssl=required setting.
17417 Defaults to @samp{#t}.
17420 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
17421 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
17422 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
17423 for caching to be used.
17424 Defaults to @samp{0}.
17427 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
17428 Time to live for cached data. After TTL expires the cached record
17429 is no longer used, *except* if the main database lookup returns internal
17430 failure. We also try to handle password changes automatically: If
17431 user's previous authentication was successful, but this one wasn't, the
17432 cache isn't used. For now this works only with plaintext
17434 Defaults to @samp{"1 hour"}.
17437 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
17438 TTL for negative hits (user not found, password mismatch).
17439 0 disables caching them completely.
17440 Defaults to @samp{"1 hour"}.
17443 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
17444 List of realms for SASL authentication mechanisms that need them.
17445 You can leave it empty if you don't want to support multiple realms.
17446 Many clients simply use the first one listed here, so keep the default
17448 Defaults to @samp{()}.
17451 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
17452 Default realm/domain to use if none was specified. This is used for
17453 both SASL realms and appending @@domain to username in plaintext
17455 Defaults to @samp{""}.
17458 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
17459 List of allowed characters in username. If the user-given username
17460 contains a character not listed in here, the login automatically fails.
17461 This is just an extra check to make sure user can't exploit any
17462 potential quote escaping vulnerabilities with SQL/LDAP databases. If
17463 you want to allow all characters, set this value to empty.
17464 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
17467 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
17468 Username character translations before it's looked up from
17469 databases. The value contains series of from -> to characters. For
17470 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
17471 translated to @samp{@@}.
17472 Defaults to @samp{""}.
17475 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
17476 Username formatting before it's looked up from databases. You can
17477 use the standard variables here, e.g.@: %Lu would lowercase the username,
17478 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
17479 change the @samp{@@} into @samp{-AT-}. This translation is done after
17480 @samp{auth-username-translation} changes.
17481 Defaults to @samp{"%Lu"}.
17484 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
17485 If you want to allow master users to log in by specifying the master
17486 username within the normal username string (i.e.@: not using SASL
17487 mechanism's support for it), you can specify the separator character
17488 here. The format is then <username><separator><master username>.
17489 UW-IMAP uses @samp{*} as the separator, so that could be a good
17491 Defaults to @samp{""}.
17494 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
17495 Username to use for users logging in with ANONYMOUS SASL
17497 Defaults to @samp{"anonymous"}.
17500 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
17501 Maximum number of dovecot-auth worker processes. They're used to
17502 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
17503 They're automatically created and destroyed as needed.
17504 Defaults to @samp{30}.
17507 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
17508 Host name to use in GSSAPI principal names. The default is to use
17509 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
17510 allow all keytab entries.
17511 Defaults to @samp{""}.
17514 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
17515 Kerberos keytab to use for the GSSAPI mechanism. Will use the
17516 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
17517 need to change the auth service to run as root to be able to read this
17519 Defaults to @samp{""}.
17522 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
17523 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
17524 and @samp{ntlm-auth} helper.
17525 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
17526 Defaults to @samp{#f}.
17529 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
17530 Path for Samba's @samp{ntlm-auth} helper binary.
17531 Defaults to @samp{"/usr/bin/ntlm_auth"}.
17534 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
17535 Time to delay before replying to failed authentications.
17536 Defaults to @samp{"2 secs"}.
17539 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
17540 Require a valid SSL client certificate or the authentication
17542 Defaults to @samp{#f}.
17545 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
17546 Take the username from client's SSL certificate, using
17547 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
17549 Defaults to @samp{#f}.
17552 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
17553 List of wanted authentication mechanisms. Supported mechanisms are:
17554 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
17555 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
17556 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
17557 @samp{disable-plaintext-auth} setting.
17560 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
17561 List of IPs or hostnames to all director servers, including ourself.
17562 Ports can be specified as ip:port. The default port is the same as what
17563 director service's @samp{inet-listener} is using.
17564 Defaults to @samp{()}.
17567 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
17568 List of IPs or hostnames to all backend mail servers. Ranges are
17569 allowed too, like 10.0.0.10-10.0.0.30.
17570 Defaults to @samp{()}.
17573 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
17574 How long to redirect users to a specific server after it no longer
17575 has any connections.
17576 Defaults to @samp{"15 min"}.
17579 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
17580 How the username is translated before being hashed. Useful values
17581 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
17582 are shared within domain.
17583 Defaults to @samp{"%Lu"}.
17586 @deftypevr {@code{dovecot-configuration} parameter} string log-path
17587 Log file to use for error messages. @samp{syslog} logs to syslog,
17588 @samp{/dev/stderr} logs to stderr.
17589 Defaults to @samp{"syslog"}.
17592 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
17593 Log file to use for informational messages. Defaults to
17595 Defaults to @samp{""}.
17598 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
17599 Log file to use for debug messages. Defaults to
17600 @samp{info-log-path}.
17601 Defaults to @samp{""}.
17604 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
17605 Syslog facility to use if you're logging to syslog. Usually if you
17606 don't want to use @samp{mail}, you'll use local0..local7. Also other
17607 standard facilities are supported.
17608 Defaults to @samp{"mail"}.
17611 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
17612 Log unsuccessful authentication attempts and the reasons why they
17614 Defaults to @samp{#f}.
17617 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
17618 In case of password mismatches, log the attempted password. Valid
17619 values are no, plain and sha1. sha1 can be useful for detecting brute
17620 force password attempts vs. user simply trying the same password over
17621 and over again. You can also truncate the value to n chars by appending
17622 ":n" (e.g.@: sha1:6).
17623 Defaults to @samp{"no"}.
17626 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
17627 Even more verbose logging for debugging purposes. Shows for example
17629 Defaults to @samp{#f}.
17632 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
17633 In case of password mismatches, log the passwords and used scheme so
17634 the problem can be debugged. Enabling this also enables
17636 Defaults to @samp{#f}.
17639 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
17640 Enable mail process debugging. This can help you figure out why
17641 Dovecot isn't finding your mails.
17642 Defaults to @samp{#f}.
17645 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
17646 Show protocol level SSL errors.
17647 Defaults to @samp{#f}.
17650 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
17651 Prefix for each line written to log file. % codes are in
17652 strftime(3) format.
17653 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
17656 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
17657 List of elements we want to log. The elements which have a
17658 non-empty variable value are joined together to form a comma-separated
17662 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
17663 Login log format. %s contains @samp{login-log-format-elements}
17664 string, %$ contains the data we want to log.
17665 Defaults to @samp{"%$: %s"}.
17668 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
17669 Log prefix for mail processes. See doc/wiki/Variables.txt for list
17670 of possible variables you can use.
17671 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
17674 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
17675 Format to use for logging mail deliveries. You can use variables:
17678 Delivery status message (e.g.@: @samp{saved to INBOX})
17690 Defaults to @samp{"msgid=%m: %$"}.
17693 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
17694 Location for users' mailboxes. The default is empty, which means
17695 that Dovecot tries to find the mailboxes automatically. This won't work
17696 if the user doesn't yet have any mail, so you should explicitly tell
17697 Dovecot the full location.
17699 If you're using mbox, giving a path to the INBOX
17700 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
17701 where the other mailboxes are kept. This is called the @emph{root mail
17702 directory}, and it must be the first path given in the
17703 @samp{mail-location} setting.
17705 There are a few special variables you can use, e.g.:
17711 user part in user@@domain, same as %u if there's no domain
17713 domain part in user@@domain, empty if there's no domain
17718 See doc/wiki/Variables.txt for full list. Some examples:
17720 @item maildir:~/Maildir
17721 @item mbox:~/mail:INBOX=/var/mail/%u
17722 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
17724 Defaults to @samp{""}.
17727 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
17728 System user and group used to access mails. If you use multiple,
17729 userdb can override these by returning uid or gid fields. You can use
17730 either numbers or names. <doc/wiki/UserIds.txt>.
17731 Defaults to @samp{""}.
17734 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
17736 Defaults to @samp{""}.
17739 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
17740 Group to enable temporarily for privileged operations. Currently
17741 this is used only with INBOX when either its initial creation or
17742 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
17744 Defaults to @samp{""}.
17747 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
17748 Grant access to these supplementary groups for mail processes.
17749 Typically these are used to set up access to shared mailboxes. Note
17750 that it may be dangerous to set these if users can create symlinks
17751 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
17752 could allow a user to delete others' mailboxes, or @code{ln -s
17753 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
17757 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
17758 Allow full file system access to clients. There's no access checks
17759 other than what the operating system does for the active UID/GID. It
17760 works with both maildir and mboxes, allowing you to prefix mailboxes
17761 names with e.g.@: @file{/path/} or @file{~user/}.
17762 Defaults to @samp{#f}.
17765 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
17766 Don't use @code{mmap()} at all. This is required if you store indexes to
17767 shared file systems (NFS or clustered file system).
17768 Defaults to @samp{#f}.
17771 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
17772 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
17773 supports @samp{O_EXCL} since version 3, so this should be safe to use
17774 nowadays by default.
17775 Defaults to @samp{#t}.
17778 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
17779 When to use fsync() or fdatasync() calls:
17782 Whenever necessary to avoid losing important data
17784 Useful with e.g.@: NFS when @code{write()}s are delayed
17786 Never use it (best performance, but crashes can lose data).
17788 Defaults to @samp{"optimized"}.
17791 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
17792 Mail storage exists in NFS. Set this to yes to make Dovecot flush
17793 NFS caches whenever needed. If you're using only a single mail server
17795 Defaults to @samp{#f}.
17798 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
17799 Mail index files also exist in NFS. Setting this to yes requires
17800 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
17801 Defaults to @samp{#f}.
17804 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
17805 Locking method for index files. Alternatives are fcntl, flock and
17806 dotlock. Dotlocking uses some tricks which may create more disk I/O
17807 than other locking methods. NFS users: flock doesn't work, remember to
17808 change @samp{mmap-disable}.
17809 Defaults to @samp{"fcntl"}.
17812 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
17813 Directory in which LDA/LMTP temporarily stores incoming mails >128
17815 Defaults to @samp{"/tmp"}.
17818 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
17819 Valid UID range for users. This is mostly to make sure that users can't
17820 log in as daemons or other system users. Note that denying root logins is
17821 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
17823 Defaults to @samp{500}.
17826 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
17828 Defaults to @samp{0}.
17831 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
17832 Valid GID range for users. Users having non-valid GID as primary group ID
17833 aren't allowed to log in. If user belongs to supplementary groups with
17834 non-valid GIDs, those groups are not set.
17835 Defaults to @samp{1}.
17838 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
17840 Defaults to @samp{0}.
17843 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
17844 Maximum allowed length for mail keyword name. It's only forced when
17845 trying to create new keywords.
17846 Defaults to @samp{50}.
17849 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
17850 List of directories under which chrooting is allowed for mail
17851 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
17852 too). This setting doesn't affect @samp{login-chroot}
17853 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
17854 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
17855 which local users can modify, that may lead to root exploit. Usually
17856 this should be done only if you don't allow shell access for users.
17857 <doc/wiki/Chrooting.txt>.
17858 Defaults to @samp{()}.
17861 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
17862 Default chroot directory for mail processes. This can be overridden
17863 for specific users in user database by giving @samp{/./} in user's home
17864 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
17865 there is no real need to do chrooting, Dovecot doesn't allow users to
17866 access files outside their mail directory anyway. If your home
17867 directories are prefixed with the chroot directory, append @samp{/.} to
17868 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
17869 Defaults to @samp{""}.
17872 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
17873 UNIX socket path to master authentication server to find users.
17874 This is used by imap (for shared users) and lda.
17875 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17878 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
17879 Directory where to look up mail plugins.
17880 Defaults to @samp{"/usr/lib/dovecot"}.
17883 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
17884 List of plugins to load for all services. Plugins specific to IMAP,
17885 LDA, etc.@: are added to this list in their own .conf files.
17886 Defaults to @samp{()}.
17889 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
17890 The minimum number of mails in a mailbox before updates are done to
17891 cache file. This allows optimizing Dovecot's behavior to do less disk
17892 writes at the cost of more disk reads.
17893 Defaults to @samp{0}.
17896 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
17897 When IDLE command is running, mailbox is checked once in a while to
17898 see if there are any new mails or other changes. This setting defines
17899 the minimum time to wait between those checks. Dovecot can also use
17900 dnotify, inotify and kqueue to find out immediately when changes
17902 Defaults to @samp{"30 secs"}.
17905 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
17906 Save mails with CR+LF instead of plain LF. This makes sending those
17907 mails take less CPU, especially with sendfile() syscall with Linux and
17908 FreeBSD. But it also creates a bit more disk I/O which may just make it
17909 slower. Also note that if other software reads the mboxes/maildirs,
17910 they may handle the extra CRs wrong and cause problems.
17911 Defaults to @samp{#f}.
17914 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
17915 By default LIST command returns all entries in maildir beginning
17916 with a dot. Enabling this option makes Dovecot return only entries
17917 which are directories. This is done by stat()ing each entry, so it
17918 causes more disk I/O.
17919 (For systems setting struct @samp{dirent->d_type} this check is free
17920 and it's done always regardless of this setting).
17921 Defaults to @samp{#f}.
17924 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
17925 When copying a message, do it with hard links whenever possible.
17926 This makes the performance much better, and it's unlikely to have any
17928 Defaults to @samp{#t}.
17931 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
17932 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
17933 directory only when its mtime changes unexpectedly or when we can't find
17934 the mail otherwise.
17935 Defaults to @samp{#f}.
17938 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
17939 Which locking methods to use for locking mbox. There are four
17944 Create <mailbox>.lock file. This is the oldest and most NFS-safe
17945 solution. If you want to use /var/mail/ like directory, the users will
17946 need write access to that directory.
17948 Same as dotlock, but if it fails because of permissions or because there
17949 isn't enough disk space, just skip it.
17951 Use this if possible. Works with NFS too if lockd is used.
17953 May not exist in all systems. Doesn't work with NFS.
17955 May not exist in all systems. Doesn't work with NFS.
17958 You can use multiple locking methods; if you do the order they're declared
17959 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
17960 locking methods as well. Some operating systems don't allow using some of
17961 them simultaneously.
17964 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
17968 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
17969 Maximum time to wait for lock (all of them) before aborting.
17970 Defaults to @samp{"5 mins"}.
17973 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
17974 If dotlock exists but the mailbox isn't modified in any way,
17975 override the lock file after this much time.
17976 Defaults to @samp{"2 mins"}.
17979 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
17980 When mbox changes unexpectedly we have to fully read it to find out
17981 what changed. If the mbox is large this can take a long time. Since
17982 the change is usually just a newly appended mail, it'd be faster to
17983 simply read the new mails. If this setting is enabled, Dovecot does
17984 this but still safely fallbacks to re-reading the whole mbox file
17985 whenever something in mbox isn't how it's expected to be. The only real
17986 downside to this setting is that if some other MUA changes message
17987 flags, Dovecot doesn't notice it immediately. Note that a full sync is
17988 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
17989 Defaults to @samp{#t}.
17992 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
17993 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
17994 EXAMINE, EXPUNGE or CHECK commands. If this is set,
17995 @samp{mbox-dirty-syncs} is ignored.
17996 Defaults to @samp{#f}.
17999 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
18000 Delay writing mbox headers until doing a full write sync (EXPUNGE
18001 and CHECK commands and when closing the mailbox). This is especially
18002 useful for POP3 where clients often delete all mails. The downside is
18003 that our changes aren't immediately visible to other MUAs.
18004 Defaults to @samp{#t}.
18007 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
18008 If mbox size is smaller than this (e.g.@: 100k), don't write index
18009 files. If an index file already exists it's still read, just not
18011 Defaults to @samp{0}.
18014 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
18015 Maximum dbox file size until it's rotated.
18016 Defaults to @samp{10000000}.
18019 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
18020 Maximum dbox file age until it's rotated. Typically in days. Day
18021 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
18023 Defaults to @samp{"1d"}.
18026 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
18027 When creating new mdbox files, immediately preallocate their size to
18028 @samp{mdbox-rotate-size}. This setting currently works only in Linux
18029 with some file systems (ext4, xfs).
18030 Defaults to @samp{#f}.
18033 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
18034 sdbox and mdbox support saving mail attachments to external files,
18035 which also allows single instance storage for them. Other backends
18036 don't support this for now.
18038 WARNING: This feature hasn't been tested much yet. Use at your own risk.
18040 Directory root where to store mail attachments. Disabled, if empty.
18041 Defaults to @samp{""}.
18044 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
18045 Attachments smaller than this aren't saved externally. It's also
18046 possible to write a plugin to disable saving specific attachments
18048 Defaults to @samp{128000}.
18051 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
18052 File system backend to use for saving attachments:
18055 No SiS done by Dovecot (but this might help FS's own deduplication)
18057 SiS with immediate byte-by-byte comparison during saving
18058 @item sis-queue posix
18059 SiS with delayed comparison and deduplication.
18061 Defaults to @samp{"sis posix"}.
18064 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
18065 Hash format to use in attachment filenames. You can add any text and
18066 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
18067 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
18068 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
18069 Defaults to @samp{"%@{sha1@}"}.
18072 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
18074 Defaults to @samp{100}.
18077 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
18079 Defaults to @samp{1000}.
18082 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
18083 Default VSZ (virtual memory size) limit for service processes.
18084 This is mainly intended to catch and kill processes that leak memory
18085 before they eat up everything.
18086 Defaults to @samp{256000000}.
18089 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
18090 Login user is internally used by login processes. This is the most
18091 untrusted user in Dovecot system. It shouldn't have access to anything
18093 Defaults to @samp{"dovenull"}.
18096 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
18097 Internal user is used by unprivileged processes. It should be
18098 separate from login user, so that login processes can't disturb other
18100 Defaults to @samp{"dovecot"}.
18103 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
18104 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
18105 Defaults to @samp{"required"}.
18108 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
18109 PEM encoded X.509 SSL/TLS certificate (public key).
18110 Defaults to @samp{"</etc/dovecot/default.pem"}.
18113 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
18114 PEM encoded SSL/TLS private key. The key is opened before
18115 dropping root privileges, so keep the key file unreadable by anyone but
18117 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
18120 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
18121 If key file is password protected, give the password here.
18122 Alternatively give it when starting dovecot with -p parameter. Since
18123 this file is often world-readable, you may want to place this setting
18124 instead to a different.
18125 Defaults to @samp{""}.
18128 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
18129 PEM encoded trusted certificate authority. Set this only if you
18130 intend to use @samp{ssl-verify-client-cert? #t}. The file should
18131 contain the CA certificate(s) followed by the matching
18132 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
18133 Defaults to @samp{""}.
18136 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
18137 Require that CRL check succeeds for client certificates.
18138 Defaults to @samp{#t}.
18141 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
18142 Request client to send a certificate. If you also want to require
18143 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
18144 Defaults to @samp{#f}.
18147 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
18148 Which field from certificate to use for username. commonName and
18149 x500UniqueIdentifier are the usual choices. You'll also need to set
18150 @samp{auth-ssl-username-from-cert? #t}.
18151 Defaults to @samp{"commonName"}.
18154 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
18155 Minimum SSL protocol version to accept.
18156 Defaults to @samp{"TLSv1"}.
18159 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
18160 SSL ciphers to use.
18161 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
18164 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
18165 SSL crypto device to use, for valid values run "openssl engine".
18166 Defaults to @samp{""}.
18169 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
18170 Address to use when sending rejection mails.
18171 %d expands to recipient domain.
18172 Defaults to @samp{"postmaster@@%d"}.
18175 @deftypevr {@code{dovecot-configuration} parameter} string hostname
18176 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
18177 and in LMTP replies. Default is the system's real hostname@@domain.
18178 Defaults to @samp{""}.
18181 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
18182 If user is over quota, return with temporary failure instead of
18184 Defaults to @samp{#f}.
18187 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
18188 Binary to use for sending mails.
18189 Defaults to @samp{"/usr/sbin/sendmail"}.
18192 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
18193 If non-empty, send mails via this SMTP host[:port] instead of
18195 Defaults to @samp{""}.
18198 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
18199 Subject: header to use for rejection mails. You can use the same
18200 variables as for @samp{rejection-reason} below.
18201 Defaults to @samp{"Rejected: %s"}.
18204 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
18205 Human readable error message for rejection mails. You can use
18218 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
18221 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
18222 Delimiter character between local-part and detail in email
18224 Defaults to @samp{"+"}.
18227 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
18228 Header where the original recipient address (SMTP's RCPT TO:
18229 address) is taken from if not available elsewhere. With dovecot-lda -a
18230 parameter overrides this. A commonly used header for this is
18232 Defaults to @samp{""}.
18235 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
18236 Should saving a mail to a nonexistent mailbox automatically create
18238 Defaults to @samp{#f}.
18241 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
18242 Should automatically created mailboxes be also automatically
18244 Defaults to @samp{#f}.
18247 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
18248 Maximum IMAP command line length. Some clients generate very long
18249 command lines with huge mailboxes, so you may need to raise this if you
18250 get "Too long argument" or "IMAP command line too large" errors
18252 Defaults to @samp{64000}.
18255 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
18256 IMAP logout format string:
18259 total number of bytes read from client
18261 total number of bytes sent to client.
18263 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
18264 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@}"}.
18267 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
18268 Override the IMAP CAPABILITY response. If the value begins with '+',
18269 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
18270 Defaults to @samp{""}.
18273 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
18274 How long to wait between "OK Still here" notifications when client
18276 Defaults to @samp{"2 mins"}.
18279 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
18280 ID field names and values to send to clients. Using * as the value
18281 makes Dovecot use the default value. The following fields have default
18282 values currently: name, version, os, os-version, support-url,
18284 Defaults to @samp{""}.
18287 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
18288 ID fields sent by client to log. * means everything.
18289 Defaults to @samp{""}.
18292 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
18293 Workarounds for various client bugs:
18296 @item delay-newmail
18297 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
18298 CHECK commands. Some clients ignore them otherwise, for example OSX
18299 Mail (<v2.1). Outlook Express breaks more badly though, without this it
18300 may show user "Message no longer in server" errors. Note that OE6
18301 still breaks even with this workaround if synchronization is set to
18304 @item tb-extra-mailbox-sep
18305 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
18306 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
18307 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
18309 @item tb-lsub-flags
18310 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
18311 This makes Thunderbird realize they aren't selectable and show them
18312 greyed out, instead of only later giving "not selectable" popup error.
18314 Defaults to @samp{()}.
18317 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
18318 Host allowed in URLAUTH URLs sent by client. "*" allows all.
18319 Defaults to @samp{""}.
18323 Whew! Lots of configuration options. The nice thing about it though is
18324 that Guix has a complete interface to Dovecot's configuration
18325 language. This allows not only a nice way to declare configurations,
18326 but also offers reflective capabilities as well: users can write code to
18327 inspect and transform configurations from within Scheme.
18329 However, it could be that you just want to get a @code{dovecot.conf} up
18330 and running. In that case, you can pass an
18331 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
18332 @code{dovecot-service}. As its name indicates, an opaque configuration
18333 does not have easy reflective capabilities.
18335 Available @code{opaque-dovecot-configuration} fields are:
18337 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
18338 The dovecot package.
18341 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
18342 The contents of the @code{dovecot.conf}, as a string.
18345 For example, if your @code{dovecot.conf} is just the empty string, you
18346 could instantiate a dovecot service like this:
18349 (dovecot-service #:config
18350 (opaque-dovecot-configuration
18354 @subsubheading OpenSMTPD Service
18356 @deffn {Scheme Variable} opensmtpd-service-type
18357 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
18358 service, whose value should be an @code{opensmtpd-configuration} object
18359 as in this example:
18362 (service opensmtpd-service-type
18363 (opensmtpd-configuration
18364 (config-file (local-file "./my-smtpd.conf"))))
18368 @deftp {Data Type} opensmtpd-configuration
18369 Data type representing the configuration of opensmtpd.
18372 @item @code{package} (default: @var{opensmtpd})
18373 Package object of the OpenSMTPD SMTP server.
18375 @item @code{config-file} (default: @code{%default-opensmtpd-file})
18376 File-like object of the OpenSMTPD configuration file to use. By default
18377 it listens on the loopback network interface, and allows for mail from
18378 users and daemons on the local machine, as well as permitting email to
18379 remote servers. Run @command{man smtpd.conf} for more information.
18384 @subsubheading Exim Service
18386 @cindex mail transfer agent (MTA)
18387 @cindex MTA (mail transfer agent)
18390 @deffn {Scheme Variable} exim-service-type
18391 This is the type of the @uref{https://exim.org, Exim} mail transfer
18392 agent (MTA), whose value should be an @code{exim-configuration} object
18393 as in this example:
18396 (service exim-service-type
18397 (exim-configuration
18398 (config-file (local-file "./my-exim.conf"))))
18402 In order to use an @code{exim-service-type} service you must also have a
18403 @code{mail-aliases-service-type} service present in your
18404 @code{operating-system} (even if it has no aliases).
18406 @deftp {Data Type} exim-configuration
18407 Data type representing the configuration of exim.
18410 @item @code{package} (default: @var{exim})
18411 Package object of the Exim server.
18413 @item @code{config-file} (default: @code{#f})
18414 File-like object of the Exim configuration file to use. If its value is
18415 @code{#f} then use the default configuration file from the package
18416 provided in @code{package}. The resulting configuration file is loaded
18417 after setting the @code{exim_user} and @code{exim_group} configuration
18423 @subsubheading Getmail service
18428 @deffn {Scheme Variable} getmail-service-type
18429 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
18430 mail retriever, whose value should be an @code{getmail-configuration}.
18433 Available @code{getmail-configuration} fields are:
18435 @deftypevr {@code{getmail-configuration} parameter} symbol name
18436 A symbol to identify the getmail service.
18438 Defaults to @samp{"unset"}.
18442 @deftypevr {@code{getmail-configuration} parameter} package package
18443 The getmail package to use.
18447 @deftypevr {@code{getmail-configuration} parameter} string user
18448 The user to run getmail as.
18450 Defaults to @samp{"getmail"}.
18454 @deftypevr {@code{getmail-configuration} parameter} string group
18455 The group to run getmail as.
18457 Defaults to @samp{"getmail"}.
18461 @deftypevr {@code{getmail-configuration} parameter} string directory
18462 The getmail directory to use.
18464 Defaults to @samp{"/var/lib/getmail/default"}.
18468 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
18469 The getmail configuration file to use.
18471 Available @code{getmail-configuration-file} fields are:
18473 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
18474 What mail account to retrieve mail from, and how to access that account.
18476 Available @code{getmail-retriever-configuration} fields are:
18478 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
18479 The type of mail retriever to use. Valid values include @samp{passwd}
18482 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
18486 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
18487 Username to login to the mail server with.
18489 Defaults to @samp{unset}.
18493 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
18494 Username to login to the mail server with.
18496 Defaults to @samp{unset}.
18500 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
18501 Port number to connect to.
18503 Defaults to @samp{#f}.
18507 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
18508 Override fields from passwd.
18510 Defaults to @samp{""}.
18514 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
18515 Override fields from passwd.
18517 Defaults to @samp{()}.
18521 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
18522 PEM-formatted key file to use for the TLS negotiation.
18524 Defaults to @samp{""}.
18528 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
18529 PEM-formatted certificate file to use for the TLS negotiation.
18531 Defaults to @samp{""}.
18535 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
18536 CA certificates to use.
18538 Defaults to @samp{""}.
18542 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
18543 Extra retriever parameters.
18545 Defaults to @samp{()}.
18551 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
18552 What to do with retrieved messages.
18554 Available @code{getmail-destination-configuration} fields are:
18556 @deftypevr {@code{getmail-destination-configuration} parameter} string type
18557 The type of mail destination. Valid values include @samp{Maildir},
18558 @samp{Mboxrd} and @samp{MDA_external}.
18560 Defaults to @samp{unset}.
18564 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
18565 The path option for the mail destination. The behaviour depends on the
18568 Defaults to @samp{""}.
18572 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
18573 Extra destination parameters
18575 Defaults to @samp{()}.
18581 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
18584 Available @code{getmail-options-configuration} fields are:
18586 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
18587 If set to @samp{0}, getmail will only print warnings and errors. A
18588 value of @samp{1} means that messages will be printed about retrieving
18589 and deleting messages. If set to @samp{2}, getmail will print messages
18590 about each of it's actions.
18592 Defaults to @samp{1}.
18596 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
18597 If true, getmail will retrieve all available messages. Otherwise it
18598 will only retrieve messages it hasn't seen previously.
18600 Defaults to @samp{#t}.
18604 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
18605 If set to true, messages will be deleted from the server after
18606 retrieving and successfully delivering them. Otherwise, messages will
18607 be left on the server.
18609 Defaults to @samp{#f}.
18613 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
18614 Getmail will delete messages this number of days after seeing them, if
18615 they have been delivered. This means messages will be left on the
18616 server this number of days after delivering them. A value of @samp{0}
18617 disabled this feature.
18619 Defaults to @samp{0}.
18623 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
18624 Delete messages larger than this of bytes after retrieving them, even if
18625 the delete and delete-after options are disabled. A value of @samp{0}
18626 disables this feature.
18628 Defaults to @samp{0}.
18632 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
18633 Retrieve messages totalling up to this number of bytes before closing
18634 the session with the server. A value of @samp{0} disables this feature.
18636 Defaults to @samp{0}.
18640 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
18641 Don't retrieve messages larger than this number of bytes. A value of
18642 @samp{0} disables this feature.
18644 Defaults to @samp{0}.
18648 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
18649 If true, getmail will add a Delivered-To header to messages.
18651 Defaults to @samp{#t}.
18655 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
18656 If set, getmail adds a Received header to the messages.
18658 Defaults to @samp{#t}.
18662 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
18663 Getmail will record a log of its actions to the named file. A value of
18664 @samp{""} disables this feature.
18666 Defaults to @samp{""}.
18670 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
18671 If true, getmail will record a log of its actions using the system
18674 Defaults to @samp{#f}.
18678 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
18679 If true, getmail will log information about messages not retrieved and
18680 the reason for not retrieving them, as well as starting and ending
18683 Defaults to @samp{#f}.
18687 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
18688 Extra options to include.
18690 Defaults to @samp{()}.
18698 @deftypevr {@code{getmail-configuration} parameter} list idle
18699 A list of mailboxes that getmail should wait on the server for new mail
18700 notifications. This depends on the server supporting the IDLE
18703 Defaults to @samp{()}.
18707 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
18708 Environment variables to set for getmail.
18710 Defaults to @samp{()}.
18714 @subsubheading Mail Aliases Service
18716 @cindex email aliases
18717 @cindex aliases, for email addresses
18719 @deffn {Scheme Variable} mail-aliases-service-type
18720 This is the type of the service which provides @code{/etc/aliases},
18721 specifying how to deliver mail to users on this system.
18724 (service mail-aliases-service-type
18725 '(("postmaster" "bob")
18726 ("bob" "bob@@example.com" "bob@@example2.com")))
18730 The configuration for a @code{mail-aliases-service-type} service is an
18731 association list denoting how to deliver mail that comes to this
18732 system. Each entry is of the form @code{(alias addresses ...)}, with
18733 @code{alias} specifying the local alias and @code{addresses} specifying
18734 where to deliver this user's mail.
18736 The aliases aren't required to exist as users on the local system. In
18737 the above example, there doesn't need to be a @code{postmaster} entry in
18738 the @code{operating-system}'s @code{user-accounts} in order to deliver
18739 the @code{postmaster} mail to @code{bob} (which subsequently would
18740 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
18742 @subsubheading GNU Mailutils IMAP4 Daemon
18743 @cindex GNU Mailutils IMAP4 Daemon
18745 @deffn {Scheme Variable} imap4d-service-type
18746 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
18747 mailutils, GNU Mailutils Manual}), whose value should be an
18748 @code{imap4d-configuration} object as in this example:
18751 (service imap4d-service-type
18752 (imap4d-configuration
18753 (config-file (local-file "imap4d.conf"))))
18757 @deftp {Data Type} imap4d-configuration
18758 Data type representing the configuration of @command{imap4d}.
18761 @item @code{package} (default: @code{mailutils})
18762 The package that provides @command{imap4d}.
18764 @item @code{config-file} (default: @code{%default-imap4d-config-file})
18765 File-like object of the configuration file to use, by default it will listen
18766 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
18767 Mailutils Manual}, for details.
18772 @node Messaging Services
18773 @subsection Messaging Services
18778 The @code{(gnu services messaging)} module provides Guix service
18779 definitions for messaging services: currently only Prosody is supported.
18781 @subsubheading Prosody Service
18783 @deffn {Scheme Variable} prosody-service-type
18784 This is the type for the @uref{https://prosody.im, Prosody XMPP
18785 communication server}. Its value must be a @code{prosody-configuration}
18786 record as in this example:
18789 (service prosody-service-type
18790 (prosody-configuration
18791 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
18794 (int-component-configuration
18795 (hostname "conference.example.net")
18797 (mod-muc (mod-muc-configuration)))))
18800 (virtualhost-configuration
18801 (domain "example.net"))))))
18804 See below for details about @code{prosody-configuration}.
18808 By default, Prosody does not need much configuration. Only one
18809 @code{virtualhosts} field is needed: it specifies the domain you wish
18812 You can perform various sanity checks on the generated configuration
18813 with the @code{prosodyctl check} command.
18815 Prosodyctl will also help you to import certificates from the
18816 @code{letsencrypt} directory so that the @code{prosody} user can access
18817 them. See @url{https://prosody.im/doc/letsencrypt}.
18820 prosodyctl --root cert import /etc/letsencrypt/live
18823 The available configuration parameters follow. Each parameter
18824 definition is preceded by its type; for example, @samp{string-list foo}
18825 indicates that the @code{foo} parameter should be specified as a list of
18826 strings. Types starting with @code{maybe-} denote parameters that won't
18827 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
18829 There is also a way to specify the configuration as a string, if you
18830 have an old @code{prosody.cfg.lua} file that you want to port over from
18831 some other system; see the end for more details.
18833 The @code{file-object} type designates either a file-like object
18834 (@pxref{G-Expressions, file-like objects}) or a file name.
18836 @c The following documentation was initially generated by
18837 @c (generate-documentation) in (gnu services messaging). Manually maintained
18838 @c documentation is better, so we shouldn't hesitate to edit below as
18839 @c needed. However if the change you want to make to this documentation
18840 @c can be done in an automated way, it's probably easier to change
18841 @c (generate-documentation) than to make it below and have to deal with
18842 @c the churn as Prosody updates.
18844 Available @code{prosody-configuration} fields are:
18846 @deftypevr {@code{prosody-configuration} parameter} package prosody
18847 The Prosody package.
18850 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
18851 Location of the Prosody data storage directory. See
18852 @url{https://prosody.im/doc/configure}.
18853 Defaults to @samp{"/var/lib/prosody"}.
18856 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
18857 Additional plugin directories. They are searched in all the specified
18858 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
18859 Defaults to @samp{()}.
18862 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
18863 Every virtual host and component needs a certificate so that clients and
18864 servers can securely verify its identity. Prosody will automatically load
18865 certificates/keys from the directory specified here.
18866 Defaults to @samp{"/etc/prosody/certs"}.
18869 @deftypevr {@code{prosody-configuration} parameter} string-list admins
18870 This is a list of accounts that are admins for the server. Note that you
18871 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
18872 @url{https://prosody.im/doc/creating_accounts}.
18873 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
18874 Defaults to @samp{()}.
18877 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
18878 Enable use of libevent for better performance under high load. See
18879 @url{https://prosody.im/doc/libevent}.
18880 Defaults to @samp{#f}.
18883 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
18884 This is the list of modules Prosody will load on startup. It looks for
18885 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
18886 Documentation on modules can be found at:
18887 @url{https://prosody.im/doc/modules}.
18888 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
18891 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
18892 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
18893 should you want to disable them then add them to this list.
18894 Defaults to @samp{()}.
18897 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
18898 Path to a text file where the shared groups are defined. If this path is
18899 empty then @samp{mod_groups} does nothing. See
18900 @url{https://prosody.im/doc/modules/mod_groups}.
18901 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
18904 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
18905 Disable account creation by default, for security. See
18906 @url{https://prosody.im/doc/creating_accounts}.
18907 Defaults to @samp{#f}.
18910 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
18911 These are the SSL/TLS-related settings. Most of them are disabled so to
18912 use Prosody's defaults. If you do not completely understand these options, do
18913 not add them to your config, it is easy to lower the security of your server
18914 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
18916 Available @code{ssl-configuration} fields are:
18918 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
18919 This determines what handshake to use.
18922 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
18923 Path to your private key file.
18926 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
18927 Path to your certificate file.
18930 @deftypevr {@code{ssl-configuration} parameter} file-object capath
18931 Path to directory containing root certificates that you wish Prosody to
18932 trust when verifying the certificates of remote servers.
18933 Defaults to @samp{"/etc/ssl/certs"}.
18936 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
18937 Path to a file containing root certificates that you wish Prosody to trust.
18938 Similar to @code{capath} but with all certificates concatenated together.
18941 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
18942 A list of verification options (these mostly map to OpenSSL's
18943 @code{set_verify()} flags).
18946 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
18947 A list of general options relating to SSL/TLS. These map to OpenSSL's
18948 @code{set_options()}. For a full list of options available in LuaSec, see the
18952 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
18953 How long a chain of certificate authorities to check when looking for a
18954 trusted root certificate.
18957 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
18958 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
18959 clients, and in what order.
18962 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
18963 A path to a file containing parameters for Diffie-Hellman key exchange. You
18964 can create such a file with:
18965 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
18968 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
18969 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
18970 @samp{"secp384r1"}.
18973 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
18974 A list of ``extra'' verification options.
18977 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
18978 Password for encrypted private keys.
18983 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
18984 Whether to force all client-to-server connections to be encrypted or not.
18985 See @url{https://prosody.im/doc/modules/mod_tls}.
18986 Defaults to @samp{#f}.
18989 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
18990 Set of mechanisms that will never be offered. See
18991 @url{https://prosody.im/doc/modules/mod_saslauth}.
18992 Defaults to @samp{("DIGEST-MD5")}.
18995 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
18996 Whether to force all server-to-server connections to be encrypted or not.
18997 See @url{https://prosody.im/doc/modules/mod_tls}.
18998 Defaults to @samp{#f}.
19001 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
19002 Whether to require encryption and certificate authentication. This
19003 provides ideal security, but requires servers you communicate with to support
19004 encryption AND present valid, trusted certificates. See
19005 @url{https://prosody.im/doc/s2s#security}.
19006 Defaults to @samp{#f}.
19009 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
19010 Many servers don't support encryption or have invalid or self-signed
19011 certificates. You can list domains here that will not be required to
19012 authenticate using certificates. They will be authenticated using DNS. See
19013 @url{https://prosody.im/doc/s2s#security}.
19014 Defaults to @samp{()}.
19017 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
19018 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
19019 valid certificates for some domains by specifying a list here. See
19020 @url{https://prosody.im/doc/s2s#security}.
19021 Defaults to @samp{()}.
19024 @deftypevr {@code{prosody-configuration} parameter} string authentication
19025 Select the authentication backend to use. The default provider stores
19026 passwords in plaintext and uses Prosody's configured data storage to store the
19027 authentication data. If you do not trust your server please see
19028 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
19029 about using the hashed backend. See also
19030 @url{https://prosody.im/doc/authentication}
19031 Defaults to @samp{"internal_plain"}.
19034 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
19035 Set logging options. Advanced logging configuration is not yet supported
19036 by the Prosody service. See @url{https://prosody.im/doc/logging}.
19037 Defaults to @samp{"*syslog"}.
19040 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
19041 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
19042 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
19045 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
19046 Maximum allowed size of the HTTP body (in bytes).
19049 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
19050 Some modules expose their own URL in various ways. This URL is built
19051 from the protocol, host and port used. If Prosody sits behind a proxy, the
19052 public URL will be @code{http-external-url} instead. See
19053 @url{https://prosody.im/doc/http#external_url}.
19056 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
19057 A host in Prosody is a domain on which user accounts can be created. For
19058 example if you want your users to have addresses like
19059 @samp{"john.smith@@example.com"} then you need to add a host
19060 @samp{"example.com"}. All options in this list will apply only to this host.
19062 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
19063 the actual physical host that Prosody is installed on. A single Prosody
19064 instance can serve many domains, each one defined as a VirtualHost entry in
19065 Prosody's configuration. Conversely a server that hosts a single domain would
19066 have just one VirtualHost entry.
19068 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
19070 Available @code{virtualhost-configuration} fields are:
19072 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:
19073 @deftypevr {@code{virtualhost-configuration} parameter} string domain
19074 Domain you wish Prosody to serve.
19079 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
19080 Components are extra services on a server which are available to clients,
19081 usually on a subdomain of the main server (such as
19082 @samp{"mycomponent.example.com"}). Example components might be chatroom
19083 servers, user directories, or gateways to other protocols.
19085 Internal components are implemented with Prosody-specific plugins. To add an
19086 internal component, you simply fill the hostname field, and the plugin you wish
19087 to use for the component.
19089 See @url{https://prosody.im/doc/components}.
19090 Defaults to @samp{()}.
19092 Available @code{int-component-configuration} fields are:
19094 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:
19095 @deftypevr {@code{int-component-configuration} parameter} string hostname
19096 Hostname of the component.
19099 @deftypevr {@code{int-component-configuration} parameter} string plugin
19100 Plugin you wish to use for the component.
19103 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
19104 Multi-user chat (MUC) is Prosody's module for allowing you to create
19105 hosted chatrooms/conferences for XMPP users.
19107 General information on setting up and using multi-user chatrooms can be found
19108 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
19109 which you should read if you are new to XMPP chatrooms.
19111 See also @url{https://prosody.im/doc/modules/mod_muc}.
19113 Available @code{mod-muc-configuration} fields are:
19115 @deftypevr {@code{mod-muc-configuration} parameter} string name
19116 The name to return in service discovery responses.
19117 Defaults to @samp{"Prosody Chatrooms"}.
19120 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
19121 If @samp{#t}, this will only allow admins to create new chatrooms.
19122 Otherwise anyone can create a room. The value @samp{"local"} restricts room
19123 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
19124 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
19125 restricts to service administrators only.
19126 Defaults to @samp{#f}.
19129 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
19130 Maximum number of history messages that will be sent to the member that has
19131 just joined the room.
19132 Defaults to @samp{20}.
19139 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
19140 External components use XEP-0114, which most standalone components
19141 support. To add an external component, you simply fill the hostname field. See
19142 @url{https://prosody.im/doc/components}.
19143 Defaults to @samp{()}.
19145 Available @code{ext-component-configuration} fields are:
19147 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:
19148 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
19149 Password which the component will use to log in.
19152 @deftypevr {@code{ext-component-configuration} parameter} string hostname
19153 Hostname of the component.
19158 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
19159 Port(s) Prosody listens on for component connections.
19160 Defaults to @samp{(5347)}.
19163 @deftypevr {@code{prosody-configuration} parameter} string component-interface
19164 Interface Prosody listens on for component connections.
19165 Defaults to @samp{"127.0.0.1"}.
19168 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
19169 Raw content that will be added to the configuration file.
19172 It could be that you just want to get a @code{prosody.cfg.lua}
19173 up and running. In that case, you can pass an
19174 @code{opaque-prosody-configuration} record as the value of
19175 @code{prosody-service-type}. As its name indicates, an opaque configuration
19176 does not have easy reflective capabilities.
19177 Available @code{opaque-prosody-configuration} fields are:
19179 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
19180 The prosody package.
19183 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
19184 The contents of the @code{prosody.cfg.lua} to use.
19187 For example, if your @code{prosody.cfg.lua} is just the empty
19188 string, you could instantiate a prosody service like this:
19191 (service prosody-service-type
19192 (opaque-prosody-configuration
19193 (prosody.cfg.lua "")))
19196 @c end of Prosody auto-generated documentation
19198 @subsubheading BitlBee Service
19200 @cindex IRC (Internet Relay Chat)
19201 @cindex IRC gateway
19202 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
19203 interface to a variety of messaging protocols such as XMPP.
19205 @defvr {Scheme Variable} bitlbee-service-type
19206 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
19207 gateway daemon. Its value is a @code{bitlbee-configuration} (see
19210 To have BitlBee listen on port 6667 on localhost, add this line to your
19214 (service bitlbee-service-type)
19218 @deftp {Data Type} bitlbee-configuration
19219 This is the configuration for BitlBee, with the following fields:
19222 @item @code{interface} (default: @code{"127.0.0.1"})
19223 @itemx @code{port} (default: @code{6667})
19224 Listen on the network interface corresponding to the IP address
19225 specified in @var{interface}, on @var{port}.
19227 When @var{interface} is @code{127.0.0.1}, only local clients can
19228 connect; when it is @code{0.0.0.0}, connections can come from any
19229 networking interface.
19231 @item @code{bitlbee} (default: @code{bitlbee})
19232 The BitlBee package to use.
19234 @item @code{plugins} (default: @code{'()})
19235 List of plugin packages to use---e.g., @code{bitlbee-discord}.
19237 @item @code{extra-settings} (default: @code{""})
19238 Configuration snippet added as-is to the BitlBee configuration file.
19242 @subsubheading Quassel Service
19244 @cindex IRC (Internet Relay Chat)
19245 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
19246 meaning that one or more clients can attach to and detach from the
19249 @defvr {Scheme Variable} quassel-service-type
19250 This is the service type for the @url{https://quassel-irc.org/,Quassel}
19251 IRC backend daemon. Its value is a @code{quassel-configuration}
19255 @deftp {Data Type} quassel-configuration
19256 This is the configuration for Quassel, with the following fields:
19259 @item @code{quassel} (default: @code{quassel})
19260 The Quassel package to use.
19262 @item @code{interface} (default: @code{"::,0.0.0.0"})
19263 @item @code{port} (default: @code{4242})
19264 Listen on the network interface(s) corresponding to the IPv4 or IPv6
19265 interfaces specified in the comma delimited @var{interface}, on
19268 @item @code{loglevel} (default: @code{"Info"})
19269 The level of logging desired. Accepted values are Debug, Info, Warning
19274 @node Telephony Services
19275 @subsection Telephony Services
19277 @cindex Murmur (VoIP server)
19278 @cindex VoIP server
19279 This section describes how to set up and run a Murmur server. Murmur is
19280 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
19283 @deftp {Data Type} murmur-configuration
19284 The service type for the Murmur server. An example configuration can
19288 (service murmur-service-type
19289 (murmur-configuration
19291 "Welcome to this Mumble server running on Guix!")
19292 (cert-required? #t) ;disallow text password logins
19293 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
19294 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
19297 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
19298 password with the command that is printed during the activation phase.
19300 It is recommended to register a normal Mumble user account
19301 and grant it admin or moderator rights.
19302 You can use the @code{mumble} client to
19303 login as new normal user, register yourself, and log out.
19304 For the next step login with the name @code{SuperUser} use
19305 the @code{SuperUser} password that you set previously,
19306 and grant your newly registered mumble user administrator or moderator
19307 rights and create some channels.
19309 Available @code{murmur-configuration} fields are:
19312 @item @code{package} (default: @code{mumble})
19313 Package that contains @code{bin/murmurd}.
19315 @item @code{user} (default: @code{"murmur"})
19316 User who will run the Murmur server.
19318 @item @code{group} (default: @code{"murmur"})
19319 Group of the user who will run the murmur server.
19321 @item @code{port} (default: @code{64738})
19322 Port on which the server will listen.
19324 @item @code{welcome-text} (default: @code{""})
19325 Welcome text sent to clients when they connect.
19327 @item @code{server-password} (default: @code{""})
19328 Password the clients have to enter in order to connect.
19330 @item @code{max-users} (default: @code{100})
19331 Maximum of users that can be connected to the server at once.
19333 @item @code{max-user-bandwidth} (default: @code{#f})
19334 Maximum voice traffic a user can send per second.
19336 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
19337 File name of the sqlite database.
19338 The service's user will become the owner of the directory.
19340 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
19341 File name of the log file.
19342 The service's user will become the owner of the directory.
19344 @item @code{autoban-attempts} (default: @code{10})
19345 Maximum number of logins a user can make in @code{autoban-timeframe}
19346 without getting auto banned for @code{autoban-time}.
19348 @item @code{autoban-timeframe} (default: @code{120})
19349 Timeframe for autoban in seconds.
19351 @item @code{autoban-time} (default: @code{300})
19352 Amount of time in seconds for which a client gets banned
19353 when violating the autoban limits.
19355 @item @code{opus-threshold} (default: @code{100})
19356 Percentage of clients that need to support opus
19357 before switching over to opus audio codec.
19359 @item @code{channel-nesting-limit} (default: @code{10})
19360 How deep channels can be nested at maximum.
19362 @item @code{channelname-regex} (default: @code{#f})
19363 A string in form of a Qt regular expression that channel names must conform to.
19365 @item @code{username-regex} (default: @code{#f})
19366 A string in form of a Qt regular expression that user names must conform to.
19368 @item @code{text-message-length} (default: @code{5000})
19369 Maximum size in bytes that a user can send in one text chat message.
19371 @item @code{image-message-length} (default: @code{(* 128 1024)})
19372 Maximum size in bytes that a user can send in one image message.
19374 @item @code{cert-required?} (default: @code{#f})
19375 If it is set to @code{#t} clients that use weak password authentication
19376 will not be accepted. Users must have completed the certificate wizard to join.
19378 @item @code{remember-channel?} (default: @code{#f})
19379 Should murmur remember the last channel each user was in when they disconnected
19380 and put them into the remembered channel when they rejoin.
19382 @item @code{allow-html?} (default: @code{#f})
19383 Should html be allowed in text messages, user comments, and channel descriptions.
19385 @item @code{allow-ping?} (default: @code{#f})
19386 Setting to true exposes the current user count, the maximum user count, and
19387 the server's maximum bandwidth per client to unauthenticated users. In the
19388 Mumble client, this information is shown in the Connect dialog.
19390 Disabling this setting will prevent public listing of the server.
19392 @item @code{bonjour?} (default: @code{#f})
19393 Should the server advertise itself in the local network through the bonjour protocol.
19395 @item @code{send-version?} (default: @code{#f})
19396 Should the murmur server version be exposed in ping requests.
19398 @item @code{log-days} (default: @code{31})
19399 Murmur also stores logs in the database, which are accessible via RPC.
19400 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
19401 or -1 to disable logging to the database.
19403 @item @code{obfuscate-ips?} (default: @code{#t})
19404 Should logged ips be obfuscated to protect the privacy of users.
19406 @item @code{ssl-cert} (default: @code{#f})
19407 File name of the SSL/TLS certificate used for encrypted connections.
19410 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
19412 @item @code{ssl-key} (default: @code{#f})
19413 Filepath to the ssl private key used for encrypted connections.
19415 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
19418 @item @code{ssl-dh-params} (default: @code{#f})
19419 File name of a PEM-encoded file with Diffie-Hellman parameters
19420 for the SSL/TLS encryption. Alternatively you set it to
19421 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
19422 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
19424 @item @code{ssl-ciphers} (default: @code{#f})
19425 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
19428 This option is specified using
19429 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
19430 OpenSSL cipher list notation}.
19432 It is recommended that you try your cipher string using 'openssl ciphers <string>'
19433 before setting it here, to get a feel for which cipher suites you will get.
19434 After setting this option, it is recommend that you inspect your Murmur log
19435 to ensure that Murmur is using the cipher suites that you expected it to.
19437 Note: Changing this option may impact the backwards compatibility of your
19438 Murmur server, and can remove the ability for older Mumble clients to be able
19441 @item @code{public-registration} (default: @code{#f})
19442 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
19444 You can optionally register your server in the public server list that the
19445 @code{mumble} client shows on startup.
19446 You cannot register your server if you have set a @code{server-password},
19447 or set @code{allow-ping} to @code{#f}.
19449 It might take a few hours until it shows up in the public list.
19451 @item @code{file} (default: @code{#f})
19452 Optional alternative override for this configuration.
19456 @deftp {Data Type} murmur-public-registration-configuration
19457 Configuration for public registration of a murmur service.
19461 This is a display name for your server. Not to be confused with the hostname.
19463 @item @code{password}
19464 A password to identify your registration.
19465 Subsequent updates will need the same password. Don't lose your password.
19468 This should be a @code{http://} or @code{https://} link to your web
19471 @item @code{hostname} (default: @code{#f})
19472 By default your server will be listed by its IP address.
19473 If it is set your server will be linked by this host name instead.
19479 @node Monitoring Services
19480 @subsection Monitoring Services
19482 @subsubheading Tailon Service
19484 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
19485 viewing and searching log files.
19487 The following example will configure the service with default values.
19488 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
19491 (service tailon-service-type)
19494 The following example customises more of the Tailon configuration,
19495 adding @command{sed} to the list of allowed commands.
19498 (service tailon-service-type
19499 (tailon-configuration
19501 (tailon-configuration-file
19502 (allowed-commands '("tail" "grep" "awk" "sed"))))))
19506 @deftp {Data Type} tailon-configuration
19507 Data type representing the configuration of Tailon.
19508 This type has the following parameters:
19511 @item @code{config-file} (default: @code{(tailon-configuration-file)})
19512 The configuration file to use for Tailon. This can be set to a
19513 @dfn{tailon-configuration-file} record value, or any gexp
19514 (@pxref{G-Expressions}).
19516 For example, to instead use a local file, the @code{local-file} function
19520 (service tailon-service-type
19521 (tailon-configuration
19522 (config-file (local-file "./my-tailon.conf"))))
19525 @item @code{package} (default: @code{tailon})
19526 The tailon package to use.
19531 @deftp {Data Type} tailon-configuration-file
19532 Data type representing the configuration options for Tailon.
19533 This type has the following parameters:
19536 @item @code{files} (default: @code{(list "/var/log")})
19537 List of files to display. The list can include strings for a single file
19538 or directory, or a list, where the first item is the name of a
19539 subsection, and the remaining items are the files or directories in that
19542 @item @code{bind} (default: @code{"localhost:8080"})
19543 Address and port to which Tailon should bind on.
19545 @item @code{relative-root} (default: @code{#f})
19546 URL path to use for Tailon, set to @code{#f} to not use a path.
19548 @item @code{allow-transfers?} (default: @code{#t})
19549 Allow downloading the log files in the web interface.
19551 @item @code{follow-names?} (default: @code{#t})
19552 Allow tailing of not-yet existent files.
19554 @item @code{tail-lines} (default: @code{200})
19555 Number of lines to read initially from each file.
19557 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
19558 Commands to allow running. By default, @code{sed} is disabled.
19560 @item @code{debug?} (default: @code{#f})
19561 Set @code{debug?} to @code{#t} to show debug messages.
19563 @item @code{wrap-lines} (default: @code{#t})
19564 Initial line wrapping state in the web interface. Set to @code{#t} to
19565 initially wrap lines (the default), or to @code{#f} to initially not
19568 @item @code{http-auth} (default: @code{#f})
19569 HTTP authentication type to use. Set to @code{#f} to disable
19570 authentication (the default). Supported values are @code{"digest"} or
19573 @item @code{users} (default: @code{#f})
19574 If HTTP authentication is enabled (see @code{http-auth}), access will be
19575 restricted to the credentials provided here. To configure users, use a
19576 list of pairs, where the first element of the pair is the username, and
19577 the 2nd element of the pair is the password.
19580 (tailon-configuration-file
19581 (http-auth "basic")
19582 (users '(("user1" . "password1")
19583 ("user2" . "password2"))))
19590 @subsubheading Darkstat Service
19592 Darkstat is a packet sniffer that captures network traffic, calculates
19593 statistics about usage, and serves reports over HTTP.
19595 @defvar {Scheme Variable} darkstat-service-type
19596 This is the service type for the
19597 @uref{https://unix4lyfe.org/darkstat/, darkstat}
19598 service, its value must be a @code{darkstat-configuration} record as in
19602 (service darkstat-service-type
19603 (darkstat-configuration
19604 (interface "eno1")))
19608 @deftp {Data Type} darkstat-configuration
19609 Data type representing the configuration of @command{darkstat}.
19612 @item @code{package} (default: @code{darkstat})
19613 The darkstat package to use.
19615 @item @code{interface}
19616 Capture traffic on the specified network interface.
19618 @item @code{port} (default: @code{"667"})
19619 Bind the web interface to the specified port.
19621 @item @code{bind-address} (default: @code{"127.0.0.1"})
19622 Bind the web interface to the specified address.
19624 @item @code{base} (default: @code{"/"})
19625 Specify the path of the base URL. This can be useful if
19626 @command{darkstat} is accessed via a reverse proxy.
19631 @subsubheading Prometheus Node Exporter Service
19633 @cindex prometheus-node-exporter
19634 The Prometheus ``node exporter'' makes hardware and operating system statistics
19635 provided by the Linux kernel available for the Prometheus monitoring system.
19636 This service should be deployed on all physical nodes and virtual machines,
19637 where monitoring these statistics is desirable.
19639 @defvar {Scheme variable} prometheus-node-exporter-service-type
19640 This is the service type for the
19641 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
19642 service, its value must be a @code{prometheus-node-exporter-configuration}
19643 record as in this example:
19646 (service prometheus-node-exporter-service-type
19647 (prometheus-node-exporter-configuration
19648 (web-listen-address ":9100")))
19652 @deftp {Data Type} prometheus-node-exporter-configuration
19653 Data type representing the configuration of @command{node_exporter}.
19656 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
19657 The prometheus-node-exporter package to use.
19659 @item @code{web-listen-address} (default: @code{":9100"})
19660 Bind the web interface to the specified address.
19665 @subsubheading Zabbix server
19666 @cindex zabbix zabbix-server
19667 Zabbix provides monitoring metrics, among others network utilization, CPU load
19668 and disk space consumption:
19671 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
19672 @item Auto-discovery of servers and network devices and interfaces.
19673 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
19674 @item Distributed monitoring with centralized web administration.
19675 @item Native high performance agents.
19676 @item SLA, and ITIL KPI metrics on reporting.
19677 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
19678 @item Remote command execution through Zabbix proxies.
19681 @c %start of fragment
19683 Available @code{zabbix-server-configuration} fields are:
19685 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
19686 The zabbix-server package.
19690 @deftypevr {@code{zabbix-server-configuration} parameter} string user
19691 User who will run the Zabbix server.
19693 Defaults to @samp{"zabbix"}.
19697 @deftypevr {@code{zabbix-server-configuration} parameter} group group
19698 Group who will run the Zabbix server.
19700 Defaults to @samp{"zabbix"}.
19704 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
19705 Database host name.
19707 Defaults to @samp{"127.0.0.1"}.
19711 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
19714 Defaults to @samp{"zabbix"}.
19718 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
19721 Defaults to @samp{"zabbix"}.
19725 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
19726 Database password. Please, use @code{include-files} with
19727 @code{DBPassword=SECRET} inside a specified file instead.
19729 Defaults to @samp{""}.
19733 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
19736 Defaults to @samp{5432}.
19740 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
19741 Specifies where log messages are written to:
19745 @code{system} - syslog.
19748 @code{file} - file specified with @code{log-file} parameter.
19751 @code{console} - standard output.
19755 Defaults to @samp{""}.
19759 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
19760 Log file name for @code{log-type} @code{file} parameter.
19762 Defaults to @samp{"/var/log/zabbix/server.log"}.
19766 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
19769 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
19773 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
19774 The location of certificate authority (CA) files for SSL server
19775 certificate verification.
19777 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
19781 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
19782 Location of SSL client certificates.
19784 Defaults to @samp{"/etc/ssl/certs"}.
19788 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
19789 Extra options will be appended to Zabbix server configuration file.
19791 Defaults to @samp{""}.
19795 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
19796 You may include individual files or all files in a directory in the
19797 configuration file.
19799 Defaults to @samp{()}.
19803 @c %end of fragment
19805 @subsubheading Zabbix agent
19806 @cindex zabbix zabbix-agent
19808 Zabbix agent gathers information for Zabbix server.
19810 @c %start of fragment
19812 Available @code{zabbix-agent-configuration} fields are:
19814 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
19815 The zabbix-agent package.
19819 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
19820 User who will run the Zabbix agent.
19822 Defaults to @samp{"zabbix"}.
19826 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
19827 Group who will run the Zabbix agent.
19829 Defaults to @samp{"zabbix"}.
19833 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
19834 Unique, case sensitive hostname which is required for active checks and
19835 must match hostname as configured on the server.
19837 Defaults to @samp{"Zabbix server"}.
19841 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
19842 Specifies where log messages are written to:
19846 @code{system} - syslog.
19849 @code{file} - file specified with @code{log-file} parameter.
19852 @code{console} - standard output.
19856 Defaults to @samp{""}.
19860 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
19861 Log file name for @code{log-type} @code{file} parameter.
19863 Defaults to @samp{"/var/log/zabbix/agent.log"}.
19867 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
19870 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
19874 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
19875 List of IP addresses, optionally in CIDR notation, or hostnames of
19876 Zabbix servers and Zabbix proxies. Incoming connections will be
19877 accepted only from the hosts listed here.
19879 Defaults to @samp{("127.0.0.1")}.
19883 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
19884 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
19885 proxies for active checks. If port is not specified, default port is
19886 used. If this parameter is not specified, active checks are disabled.
19888 Defaults to @samp{("127.0.0.1")}.
19892 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
19893 Extra options will be appended to Zabbix server configuration file.
19895 Defaults to @samp{""}.
19899 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
19900 You may include individual files or all files in a directory in the
19901 configuration file.
19903 Defaults to @samp{()}.
19907 @c %end of fragment
19909 @subsubheading Zabbix front-end
19910 @cindex zabbix zabbix-front-end
19912 This service provides a WEB interface to Zabbix server.
19914 @c %start of fragment
19916 Available @code{zabbix-front-end-configuration} fields are:
19918 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
19919 NGINX configuration.
19923 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
19924 Database host name.
19926 Defaults to @samp{"localhost"}.
19930 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
19933 Defaults to @samp{5432}.
19937 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
19940 Defaults to @samp{"zabbix"}.
19944 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
19947 Defaults to @samp{"zabbix"}.
19951 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
19952 Database password. Please, use @code{db-secret-file} instead.
19954 Defaults to @samp{""}.
19958 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
19959 Secret file which will be appended to @file{zabbix.conf.php} file. This
19960 file contains credentials for use by Zabbix front-end. You are expected
19961 to create it manually.
19963 Defaults to @samp{""}.
19967 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
19968 Zabbix server hostname.
19970 Defaults to @samp{"localhost"}.
19974 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
19975 Zabbix server port.
19977 Defaults to @samp{10051}.
19982 @c %end of fragment
19984 @node Kerberos Services
19985 @subsection Kerberos Services
19988 The @code{(gnu services kerberos)} module provides services relating to
19989 the authentication protocol @dfn{Kerberos}.
19991 @subsubheading Krb5 Service
19993 Programs using a Kerberos client library normally
19994 expect a configuration file in @file{/etc/krb5.conf}.
19995 This service generates such a file from a definition provided in the
19996 operating system declaration.
19997 It does not cause any daemon to be started.
19999 No ``keytab'' files are provided by this service---you must explicitly create them.
20000 This service is known to work with the MIT client library, @code{mit-krb5}.
20001 Other implementations have not been tested.
20003 @defvr {Scheme Variable} krb5-service-type
20004 A service type for Kerberos 5 clients.
20008 Here is an example of its use:
20010 (service krb5-service-type
20011 (krb5-configuration
20012 (default-realm "EXAMPLE.COM")
20013 (allow-weak-crypto? #t)
20016 (name "EXAMPLE.COM")
20017 (admin-server "groucho.example.com")
20018 (kdc "karl.example.com"))
20021 (admin-server "kerb-admin.argrx.edu")
20022 (kdc "keys.argrx.edu"))))))
20026 This example provides a Kerberos@tie{}5 client configuration which:
20028 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
20029 of which have distinct administration servers and key distribution centers;
20030 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
20031 specified by clients;
20032 @item Accepts services which only support encryption types known to be weak.
20035 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
20036 Only the most commonly used ones are described here.
20037 For a full list, and more detailed explanation of each, see the MIT
20038 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
20042 @deftp {Data Type} krb5-realm
20043 @cindex realm, kerberos
20046 This field is a string identifying the name of the realm.
20047 A common convention is to use the fully qualified DNS name of your organization,
20048 converted to upper case.
20050 @item @code{admin-server}
20051 This field is a string identifying the host where the administration server is
20055 This field is a string identifying the key distribution center
20060 @deftp {Data Type} krb5-configuration
20063 @item @code{allow-weak-crypto?} (default: @code{#f})
20064 If this flag is @code{#t} then services which only offer encryption algorithms
20065 known to be weak will be accepted.
20067 @item @code{default-realm} (default: @code{#f})
20068 This field should be a string identifying the default Kerberos
20069 realm for the client.
20070 You should set this field to the name of your Kerberos realm.
20071 If this value is @code{#f}
20072 then a realm must be specified with every Kerberos principal when invoking programs
20073 such as @command{kinit}.
20075 @item @code{realms}
20076 This should be a non-empty list of @code{krb5-realm} objects, which clients may
20078 Normally, one of them will have a @code{name} field matching the @code{default-realm}
20084 @subsubheading PAM krb5 Service
20087 The @code{pam-krb5} service allows for login authentication and password
20088 management via Kerberos.
20089 You will need this service if you want PAM enabled applications to authenticate
20090 users using Kerberos.
20092 @defvr {Scheme Variable} pam-krb5-service-type
20093 A service type for the Kerberos 5 PAM module.
20096 @deftp {Data Type} pam-krb5-configuration
20097 Data type representing the configuration of the Kerberos 5 PAM module.
20098 This type has the following parameters:
20100 @item @code{pam-krb5} (default: @code{pam-krb5})
20101 The pam-krb5 package to use.
20103 @item @code{minimum-uid} (default: @code{1000})
20104 The smallest user ID for which Kerberos authentications should be attempted.
20105 Local accounts with lower values will silently fail to authenticate.
20110 @node LDAP Services
20111 @subsection LDAP Services
20113 @cindex nslcd, LDAP service
20115 The @code{(gnu services authentication)} module provides the
20116 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
20117 server. In addition to configuring the service itself, you may want to add
20118 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
20119 Switch} for detailed information.
20121 Here is a simple operating system declaration with a default configuration of
20122 the @code{nslcd-service-type} and a Name Service Switch configuration that
20123 consults the @code{ldap} name service last:
20126 (use-service-modules authentication)
20127 (use-modules (gnu system nss))
20133 (service nslcd-service-type)
20134 (service dhcp-client-service-type)
20136 (name-service-switch
20137 (let ((services (list (name-service (name "db"))
20138 (name-service (name "files"))
20139 (name-service (name "ldap")))))
20140 (name-service-switch
20141 (inherit %mdns-host-lookup-nss)
20142 (password services)
20145 (netgroup services)
20146 (gshadow services)))))
20149 @c %start of generated documentation for nslcd-configuration
20151 Available @code{nslcd-configuration} fields are:
20153 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
20154 The @code{nss-pam-ldapd} package to use.
20158 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
20159 The number of threads to start that can handle requests and perform LDAP
20160 queries. Each thread opens a separate connection to the LDAP server.
20161 The default is to start 5 threads.
20163 Defaults to @samp{disabled}.
20167 @deftypevr {@code{nslcd-configuration} parameter} string uid
20168 This specifies the user id with which the daemon should be run.
20170 Defaults to @samp{"nslcd"}.
20174 @deftypevr {@code{nslcd-configuration} parameter} string gid
20175 This specifies the group id with which the daemon should be run.
20177 Defaults to @samp{"nslcd"}.
20181 @deftypevr {@code{nslcd-configuration} parameter} log-option log
20182 This option controls the way logging is done via a list containing
20183 SCHEME and LEVEL. The SCHEME argument may either be the symbols
20184 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
20185 argument is optional and specifies the log level. The log level may be
20186 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
20187 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
20188 specified log level or higher are logged.
20190 Defaults to @samp{("/var/log/nslcd" info)}.
20194 @deftypevr {@code{nslcd-configuration} parameter} list uri
20195 The list of LDAP server URIs. Normally, only the first server will be
20196 used with the following servers as fall-back.
20198 Defaults to @samp{("ldap://localhost:389/")}.
20202 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
20203 The version of the LDAP protocol to use. The default is to use the
20204 maximum version supported by the LDAP library.
20206 Defaults to @samp{disabled}.
20210 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
20211 Specifies the distinguished name with which to bind to the directory
20212 server for lookups. The default is to bind anonymously.
20214 Defaults to @samp{disabled}.
20218 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
20219 Specifies the credentials with which to bind. This option is only
20220 applicable when used with binddn.
20222 Defaults to @samp{disabled}.
20226 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
20227 Specifies the distinguished name to use when the root user tries to
20228 modify a user's password using the PAM module.
20230 Defaults to @samp{disabled}.
20234 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
20235 Specifies the credentials with which to bind if the root user tries to
20236 change a user's password. This option is only applicable when used with
20239 Defaults to @samp{disabled}.
20243 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
20244 Specifies the SASL mechanism to be used when performing SASL
20247 Defaults to @samp{disabled}.
20251 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
20252 Specifies the SASL realm to be used when performing SASL authentication.
20254 Defaults to @samp{disabled}.
20258 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
20259 Specifies the authentication identity to be used when performing SASL
20262 Defaults to @samp{disabled}.
20266 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
20267 Specifies the authorization identity to be used when performing SASL
20270 Defaults to @samp{disabled}.
20274 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
20275 Determines whether the LDAP server host name should be canonicalised. If
20276 this is enabled the LDAP library will do a reverse host name lookup. By
20277 default, it is left up to the LDAP library whether this check is
20280 Defaults to @samp{disabled}.
20284 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
20285 Set the name for the GSS-API Kerberos credentials cache.
20287 Defaults to @samp{disabled}.
20291 @deftypevr {@code{nslcd-configuration} parameter} string base
20292 The directory search base.
20294 Defaults to @samp{"dc=example,dc=com"}.
20298 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
20299 Specifies the search scope (subtree, onelevel, base or children). The
20300 default scope is subtree; base scope is almost never useful for name
20301 service lookups; children scope is not supported on all servers.
20303 Defaults to @samp{(subtree)}.
20307 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
20308 Specifies the policy for dereferencing aliases. The default policy is
20309 to never dereference aliases.
20311 Defaults to @samp{disabled}.
20315 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
20316 Specifies whether automatic referral chasing should be enabled. The
20317 default behaviour is to chase referrals.
20319 Defaults to @samp{disabled}.
20323 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
20324 This option allows for custom attributes to be looked up instead of the
20325 default RFC 2307 attributes. It is a list of maps, each consisting of
20326 the name of a map, the RFC 2307 attribute to match and the query
20327 expression for the attribute as it is available in the directory.
20329 Defaults to @samp{()}.
20333 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
20334 A list of filters consisting of the name of a map to which the filter
20335 applies and an LDAP search filter expression.
20337 Defaults to @samp{()}.
20341 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
20342 Specifies the time limit in seconds to use when connecting to the
20343 directory server. The default value is 10 seconds.
20345 Defaults to @samp{disabled}.
20349 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
20350 Specifies the time limit (in seconds) to wait for a response from the
20351 LDAP server. A value of zero, which is the default, is to wait
20352 indefinitely for searches to be completed.
20354 Defaults to @samp{disabled}.
20358 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
20359 Specifies the period if inactivity (in seconds) after which the con‐
20360 nection to the LDAP server will be closed. The default is not to time
20363 Defaults to @samp{disabled}.
20367 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
20368 Specifies the number of seconds to sleep when connecting to all LDAP
20369 servers fails. By default one second is waited between the first
20370 failure and the first retry.
20372 Defaults to @samp{disabled}.
20376 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
20377 Specifies the time after which the LDAP server is considered to be
20378 permanently unavailable. Once this time is reached retries will be done
20379 only once per this time period. The default value is 10 seconds.
20381 Defaults to @samp{disabled}.
20385 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
20386 Specifies whether to use SSL/TLS or not (the default is not to). If
20387 'start-tls is specified then StartTLS is used rather than raw LDAP over
20390 Defaults to @samp{disabled}.
20394 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
20395 Specifies what checks to perform on a server-supplied certificate. The
20396 meaning of the values is described in the ldap.conf(5) manual page.
20398 Defaults to @samp{disabled}.
20402 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
20403 Specifies the directory containing X.509 certificates for peer authen‐
20404 tication. This parameter is ignored when using GnuTLS.
20406 Defaults to @samp{disabled}.
20410 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
20411 Specifies the path to the X.509 certificate for peer authentication.
20413 Defaults to @samp{disabled}.
20417 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
20418 Specifies the path to an entropy source. This parameter is ignored when
20421 Defaults to @samp{disabled}.
20425 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
20426 Specifies the ciphers to use for TLS as a string.
20428 Defaults to @samp{disabled}.
20432 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
20433 Specifies the path to the file containing the local certificate for
20434 client TLS authentication.
20436 Defaults to @samp{disabled}.
20440 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
20441 Specifies the path to the file containing the private key for client TLS
20444 Defaults to @samp{disabled}.
20448 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
20449 Set this to a number greater than 0 to request paged results from the
20450 LDAP server in accordance with RFC2696. The default (0) is to not
20451 request paged results.
20453 Defaults to @samp{disabled}.
20457 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
20458 This option prevents group membership lookups through LDAP for the
20459 specified users. Alternatively, the value 'all-local may be used. With
20460 that value nslcd builds a full list of non-LDAP users on startup.
20462 Defaults to @samp{disabled}.
20466 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
20467 This option ensures that LDAP users with a numeric user id lower than
20468 the specified value are ignored.
20470 Defaults to @samp{disabled}.
20474 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
20475 This option specifies an offset that is added to all LDAP numeric user
20476 ids. This can be used to avoid user id collisions with local users.
20478 Defaults to @samp{disabled}.
20482 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
20483 This option specifies an offset that is added to all LDAP numeric group
20484 ids. This can be used to avoid user id collisions with local groups.
20486 Defaults to @samp{disabled}.
20490 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
20491 If this option is set, the member attribute of a group may point to
20492 another group. Members of nested groups are also returned in the higher
20493 level group and parent groups are returned when finding groups for a
20494 specific user. The default is not to perform extra searches for nested
20497 Defaults to @samp{disabled}.
20501 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
20502 If this option is set, the group member list is not retrieved when
20503 looking up groups. Lookups for finding which groups a user belongs to
20504 will remain functional so the user will likely still get the correct
20505 groups assigned on login.
20507 Defaults to @samp{disabled}.
20511 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
20512 If this option is set, functions which cause all user/group entries to
20513 be loaded from the directory will not succeed in doing so. This can
20514 dramatically reduce LDAP server load in situations where there are a
20515 great number of users and/or groups. This option is not recommended for
20516 most configurations.
20518 Defaults to @samp{disabled}.
20522 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
20523 This option can be used to specify how user and group names are verified
20524 within the system. This pattern is used to check all user and group
20525 names that are requested and returned from LDAP.
20527 Defaults to @samp{disabled}.
20531 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
20532 This specifies whether or not to perform searches using case-insensitive
20533 matching. Enabling this could open up the system to authorization
20534 bypass vulnerabilities and introduce nscd cache poisoning
20535 vulnerabilities which allow denial of service.
20537 Defaults to @samp{disabled}.
20541 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
20542 This option specifies whether password policy controls are requested and
20543 handled from the LDAP server when performing user authentication.
20545 Defaults to @samp{disabled}.
20549 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
20550 By default nslcd performs an LDAP search with the user's credentials
20551 after BIND (authentication) to ensure that the BIND operation was
20552 successful. The default search is a simple check to see if the user's
20553 DN exists. A search filter can be specified that will be used instead.
20554 It should return at least one entry.
20556 Defaults to @samp{disabled}.
20560 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
20561 This option allows flexible fine tuning of the authorisation check that
20562 should be performed. The search filter specified is executed and if any
20563 entries match, access is granted, otherwise access is denied.
20565 Defaults to @samp{disabled}.
20569 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
20570 If this option is set password modification using pam_ldap will be
20571 denied and the specified message will be presented to the user instead.
20572 The message can be used to direct the user to an alternative means of
20573 changing their password.
20575 Defaults to @samp{disabled}.
20579 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
20580 List of pam service names for which LDAP authentication should suffice.
20582 Defaults to @samp{()}.
20586 @c %end of generated documentation for nslcd-configuration
20590 @subsection Web Services
20595 The @code{(gnu services web)} module provides the Apache HTTP Server,
20596 the nginx web server, and also a fastcgi wrapper daemon.
20598 @subsubheading Apache HTTP Server
20600 @deffn {Scheme Variable} httpd-service-type
20601 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
20602 (@dfn{httpd}). The value for this service type is a
20603 @code{httpd-configuration} record.
20605 A simple example configuration is given below.
20608 (service httpd-service-type
20609 (httpd-configuration
20612 (server-name "www.example.com")
20613 (document-root "/srv/http/www.example.com")))))
20616 Other services can also extend the @code{httpd-service-type} to add to
20620 (simple-service 'www.example.com-server httpd-service-type
20624 (list (string-join '("ServerName www.example.com"
20625 "DocumentRoot /srv/http/www.example.com")
20630 The details for the @code{httpd-configuration}, @code{httpd-module},
20631 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
20634 @deffn {Data Type} httpd-configuration
20635 This data type represents the configuration for the httpd service.
20638 @item @code{package} (default: @code{httpd})
20639 The httpd package to use.
20641 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20642 The pid file used by the shepherd-service.
20644 @item @code{config} (default: @code{(httpd-config-file)})
20645 The configuration file to use with the httpd service. The default value
20646 is a @code{httpd-config-file} record, but this can also be a different
20647 G-expression that generates a file, for example a @code{plain-file}. A
20648 file outside of the store can also be specified through a string.
20653 @deffn {Data Type} httpd-module
20654 This data type represents a module for the httpd service.
20658 The name of the module.
20661 The file for the module. This can be relative to the httpd package being
20662 used, the absolute location of a file, or a G-expression for a file
20663 within the store, for example @code{(file-append mod-wsgi
20664 "/modules/mod_wsgi.so")}.
20669 @defvr {Scheme Variable} %default-httpd-modules
20670 A default list of @code{httpd-module} objects.
20673 @deffn {Data Type} httpd-config-file
20674 This data type represents a configuration file for the httpd service.
20677 @item @code{modules} (default: @code{%default-httpd-modules})
20678 The modules to load. Additional modules can be added here, or loaded by
20679 additional configuration.
20681 For example, in order to handle requests for PHP files, you can use Apache’s
20682 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
20685 (service httpd-service-type
20686 (httpd-configuration
20691 (name "proxy_module")
20692 (file "modules/mod_proxy.so"))
20694 (name "proxy_fcgi_module")
20695 (file "modules/mod_proxy_fcgi.so"))
20696 %default-httpd-modules))
20697 (extra-config (list "\
20698 <FilesMatch \\.php$>
20699 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
20700 </FilesMatch>"))))))
20701 (service php-fpm-service-type
20702 (php-fpm-configuration
20703 (socket "/var/run/php-fpm.sock")
20704 (socket-group "httpd")))
20707 @item @code{server-root} (default: @code{httpd})
20708 The @code{ServerRoot} in the configuration file, defaults to the httpd
20709 package. Directives including @code{Include} and @code{LoadModule} are
20710 taken as relative to the server root.
20712 @item @code{server-name} (default: @code{#f})
20713 The @code{ServerName} in the configuration file, used to specify the
20714 request scheme, hostname and port that the server uses to identify
20717 This doesn't need to be set in the server config, and can be specified
20718 in virtual hosts. The default is @code{#f} to not specify a
20721 @item @code{document-root} (default: @code{"/srv/http"})
20722 The @code{DocumentRoot} from which files will be served.
20724 @item @code{listen} (default: @code{'("80")})
20725 The list of values for the @code{Listen} directives in the config
20726 file. The value should be a list of strings, when each string can
20727 specify the port number to listen on, and optionally the IP address and
20730 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20731 The @code{PidFile} to use. This should match the @code{pid-file} set in
20732 the @code{httpd-configuration} so that the Shepherd service is
20733 configured correctly.
20735 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
20736 The @code{ErrorLog} to which the server will log errors.
20738 @item @code{user} (default: @code{"httpd"})
20739 The @code{User} which the server will answer requests as.
20741 @item @code{group} (default: @code{"httpd"})
20742 The @code{Group} which the server will answer requests as.
20744 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
20745 A flat list of strings and G-expressions which will be added to the end
20746 of the configuration file.
20748 Any values which the service is extended with will be appended to this
20754 @deffn {Data Type} httpd-virtualhost
20755 This data type represents a virtualhost configuration block for the httpd service.
20757 These should be added to the extra-config for the httpd-service.
20760 (simple-service 'www.example.com-server httpd-service-type
20764 (list (string-join '("ServerName www.example.com"
20765 "DocumentRoot /srv/http/www.example.com")
20770 @item @code{addresses-and-ports}
20771 The addresses and ports for the @code{VirtualHost} directive.
20773 @item @code{contents}
20774 The contents of the @code{VirtualHost} directive, this should be a list
20775 of strings and G-expressions.
20780 @subsubheading NGINX
20782 @deffn {Scheme Variable} nginx-service-type
20783 Service type for the @uref{https://nginx.org/,NGinx} web server. The
20784 value for this service type is a @code{<nginx-configuration>} record.
20786 A simple example configuration is given below.
20789 (service nginx-service-type
20790 (nginx-configuration
20792 (list (nginx-server-configuration
20793 (server-name '("www.example.com"))
20794 (root "/srv/http/www.example.com"))))))
20797 In addition to adding server blocks to the service configuration
20798 directly, this service can be extended by other services to add server
20799 blocks, as in this example:
20802 (simple-service 'my-extra-server nginx-service-type
20803 (list (nginx-server-configuration
20804 (root "/srv/http/extra-website")
20805 (try-files (list "$uri" "$uri/index.html")))))
20809 At startup, @command{nginx} has not yet read its configuration file, so
20810 it uses a default file to log error messages. If it fails to load its
20811 configuration file, that is where error messages are logged. After the
20812 configuration file is loaded, the default error log file changes as per
20813 configuration. In our case, startup error messages can be found in
20814 @file{/var/run/nginx/logs/error.log}, and after configuration in
20815 @file{/var/log/nginx/error.log}. The second location can be changed
20816 with the @var{log-directory} configuration option.
20818 @deffn {Data Type} nginx-configuration
20819 This data type represents the configuration for NGinx. Some
20820 configuration can be done through this and the other provided record
20821 types, or alternatively, a config file can be provided.
20824 @item @code{nginx} (default: @code{nginx})
20825 The nginx package to use.
20827 @item @code{log-directory} (default: @code{"/var/log/nginx"})
20828 The directory to which NGinx will write log files.
20830 @item @code{run-directory} (default: @code{"/var/run/nginx"})
20831 The directory in which NGinx will create a pid file, and write temporary
20834 @item @code{server-blocks} (default: @code{'()})
20835 A list of @dfn{server blocks} to create in the generated configuration
20836 file, the elements should be of type
20837 @code{<nginx-server-configuration>}.
20839 The following example would setup NGinx to serve @code{www.example.com}
20840 from the @code{/srv/http/www.example.com} directory, without using
20843 (service nginx-service-type
20844 (nginx-configuration
20846 (list (nginx-server-configuration
20847 (server-name '("www.example.com"))
20848 (root "/srv/http/www.example.com"))))))
20851 @item @code{upstream-blocks} (default: @code{'()})
20852 A list of @dfn{upstream blocks} to create in the generated configuration
20853 file, the elements should be of type
20854 @code{<nginx-upstream-configuration>}.
20856 Configuring upstreams through the @code{upstream-blocks} can be useful
20857 when combined with @code{locations} in the
20858 @code{<nginx-server-configuration>} records. The following example
20859 creates a server configuration with one location configuration, that
20860 will proxy requests to a upstream configuration, which will handle
20861 requests with two servers.
20866 (nginx-configuration
20868 (list (nginx-server-configuration
20869 (server-name '("www.example.com"))
20870 (root "/srv/http/www.example.com")
20873 (nginx-location-configuration
20875 (body '("proxy_pass http://server-proxy;"))))))))
20877 (list (nginx-upstream-configuration
20878 (name "server-proxy")
20879 (servers (list "server1.example.com"
20880 "server2.example.com")))))))
20883 @item @code{file} (default: @code{#f})
20884 If a configuration @var{file} is provided, this will be used, rather than
20885 generating a configuration file from the provided @code{log-directory},
20886 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
20887 proper operation, these arguments should match what is in @var{file} to ensure
20888 that the directories are created when the service is activated.
20890 This can be useful if you have an existing configuration file, or it's
20891 not possible to do what is required through the other parts of the
20892 nginx-configuration record.
20894 @item @code{server-names-hash-bucket-size} (default: @code{#f})
20895 Bucket size for the server names hash tables, defaults to @code{#f} to
20896 use the size of the processors cache line.
20898 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
20899 Maximum bucket size for the server names hash tables.
20901 @item @code{modules} (default: @code{'()})
20902 List of nginx dynamic modules to load. This should be a list of file
20903 names of loadable modules, as in this example:
20908 (file-append nginx-accept-language-module "\
20909 /etc/nginx/modules/ngx_http_accept_language_module.so")))
20912 @item @code{global-directives} (default: @code{'((events . ()))})
20913 Association list of global directives for the top level of the nginx
20914 configuration. Values may themselves be association lists.
20918 `((worker_processes . 16)
20920 (events . ((worker_connections . 1024)))))
20923 @item @code{extra-content} (default: @code{""})
20924 Extra content for the @code{http} block. Should be string or a string
20925 valued G-expression.
20930 @deftp {Data Type} nginx-server-configuration
20931 Data type representing the configuration of an nginx server block.
20932 This type has the following parameters:
20935 @item @code{listen} (default: @code{'("80" "443 ssl")})
20936 Each @code{listen} directive sets the address and port for IP, or the
20937 path for a UNIX-domain socket on which the server will accept requests.
20938 Both address and port, or only address or only port can be specified.
20939 An address may also be a hostname, for example:
20942 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
20945 @item @code{server-name} (default: @code{(list 'default)})
20946 A list of server names this server represents. @code{'default} represents the
20947 default server for connections matching no other server.
20949 @item @code{root} (default: @code{"/srv/http"})
20950 Root of the website nginx will serve.
20952 @item @code{locations} (default: @code{'()})
20953 A list of @dfn{nginx-location-configuration} or
20954 @dfn{nginx-named-location-configuration} records to use within this
20957 @item @code{index} (default: @code{(list "index.html")})
20958 Index files to look for when clients ask for a directory. If it cannot be found,
20959 Nginx will send the list of files in the directory.
20961 @item @code{try-files} (default: @code{'()})
20962 A list of files whose existence is checked in the specified order.
20963 @code{nginx} will use the first file it finds to process the request.
20965 @item @code{ssl-certificate} (default: @code{#f})
20966 Where to find the certificate for secure connections. Set it to @code{#f} if
20967 you don't have a certificate or you don't want to use HTTPS.
20969 @item @code{ssl-certificate-key} (default: @code{#f})
20970 Where to find the private key for secure connections. Set it to @code{#f} if
20971 you don't have a key or you don't want to use HTTPS.
20973 @item @code{server-tokens?} (default: @code{#f})
20974 Whether the server should add its configuration to response.
20976 @item @code{raw-content} (default: @code{'()})
20977 A list of raw lines added to the server block.
20982 @deftp {Data Type} nginx-upstream-configuration
20983 Data type representing the configuration of an nginx @code{upstream}
20984 block. This type has the following parameters:
20988 Name for this group of servers.
20990 @item @code{servers}
20991 Specify the addresses of the servers in the group. The address can be
20992 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
20993 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
20994 prefix @samp{unix:}. For addresses using an IP address or domain name,
20995 the default port is 80, and a different port can be specified
21001 @deftp {Data Type} nginx-location-configuration
21002 Data type representing the configuration of an nginx @code{location}
21003 block. This type has the following parameters:
21007 URI which this location block matches.
21009 @anchor{nginx-location-configuration body}
21011 Body of the location block, specified as a list of strings. This can contain
21013 configuration directives. For example, to pass requests to a upstream
21014 server group defined using an @code{nginx-upstream-configuration} block,
21015 the following directive would be specified in the body @samp{(list "proxy_pass
21016 http://upstream-name;")}.
21021 @deftp {Data Type} nginx-named-location-configuration
21022 Data type representing the configuration of an nginx named location
21023 block. Named location blocks are used for request redirection, and not
21024 used for regular request processing. This type has the following
21029 Name to identify this location block.
21032 @xref{nginx-location-configuration body}, as the body for named location
21033 blocks can be used in a similar way to the
21034 @code{nginx-location-configuration body}. One restriction is that the
21035 body of a named location block cannot contain location blocks.
21040 @subsubheading Varnish Cache
21042 Varnish is a fast cache server that sits in between web applications
21043 and end users. It proxies requests from clients and caches the
21044 accessed URLs such that multiple requests for the same resource only
21045 creates one request to the back-end.
21047 @defvr {Scheme Variable} varnish-service-type
21048 Service type for the Varnish daemon.
21051 @deftp {Data Type} varnish-configuration
21052 Data type representing the @code{varnish} service configuration.
21053 This type has the following parameters:
21056 @item @code{package} (default: @code{varnish})
21057 The Varnish package to use.
21059 @item @code{name} (default: @code{"default"})
21060 A name for this Varnish instance. Varnish will create a directory in
21061 @file{/var/varnish/} with this name and keep temporary files there. If
21062 the name starts with a forward slash, it is interpreted as an absolute
21065 Pass the @code{-n} argument to other Varnish programs to connect to the
21066 named instance, e.g.@: @command{varnishncsa -n default}.
21068 @item @code{backend} (default: @code{"localhost:8080"})
21069 The backend to use. This option has no effect if @code{vcl} is set.
21071 @item @code{vcl} (default: #f)
21072 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
21073 is @code{#f}, Varnish will proxy @code{backend} using the default
21074 configuration. Otherwise this must be a file-like object with valid
21077 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
21078 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
21079 can do something along these lines:
21082 (define %gnu-mirror
21083 (plain-file "gnu.vcl"
21085 backend gnu @{ .host = \"www.gnu.org\"; @}"))
21089 (services (cons (service varnish-service-type
21090 (varnish-configuration
21092 (vcl %gnu-mirror)))
21096 The configuration of an already running Varnish instance can be inspected
21097 and changed using the @command{varnishadm} program.
21099 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
21100 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
21101 comprehensive documentation on Varnish and its configuration language.
21103 @item @code{listen} (default: @code{'("localhost:80")})
21104 List of addresses Varnish will listen on.
21106 @item @code{storage} (default: @code{'("malloc,128m")})
21107 List of storage backends that will be available in VCL.
21109 @item @code{parameters} (default: @code{'()})
21110 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
21112 @item @code{extra-options} (default: @code{'()})
21113 Additional arguments to pass to the @command{varnishd} process.
21118 @subsubheading Patchwork
21120 Patchwork is a patch tracking system. It can collect patches sent to a
21121 mailing list, and display them in a web interface.
21123 @defvr {Scheme Variable} patchwork-service-type
21124 Service type for Patchwork.
21127 The following example is an example of a minimal service for Patchwork, for
21128 the @code{patchwork.example.com} domain.
21131 (service patchwork-service-type
21132 (patchwork-configuration
21133 (domain "patchwork.example.com")
21135 (patchwork-settings-module
21136 (allowed-hosts (list domain))
21137 (default-from-email "patchwork@@patchwork.example.com")))
21138 (getmail-retriever-config
21139 (getmail-retriever-configuration
21140 (type "SimpleIMAPSSLRetriever")
21141 (server "imap.example.com")
21143 (username "patchwork")
21145 (list (file-append coreutils "/bin/cat")
21146 "/etc/getmail-patchwork-imap-password"))
21148 '((mailboxes . ("Patches"))))))))
21152 There are three records for configuring the Patchwork service. The
21153 @code{<patchwork-configuration>} relates to the configuration for Patchwork
21154 within the HTTPD service.
21156 The @code{settings-module} field within the @code{<patchwork-configuration>}
21157 record can be populated with the @code{<patchwork-settings-module>} record,
21158 which describes a settings module that is generated within the Guix store.
21160 For the @code{database-configuration} field within the
21161 @code{<patchwork-settings-module>}, the
21162 @code{<patchwork-database-configuration>} must be used.
21164 @deftp {Data Type} patchwork-configuration
21165 Data type representing the Patchwork service configuration. This type has the
21166 following parameters:
21169 @item @code{patchwork} (default: @code{patchwork})
21170 The Patchwork package to use.
21172 @item @code{domain}
21173 The domain to use for Patchwork, this is used in the HTTPD service virtual
21176 @item @code{settings-module}
21177 The settings module to use for Patchwork. As a Django application, Patchwork
21178 is configured with a Python module containing the settings. This can either be
21179 an instance of the @code{<patchwork-settings-module>} record, any other record
21180 that represents the settings in the store, or a directory outside of the
21183 @item @code{static-path} (default: @code{"/static/"})
21184 The path under which the HTTPD service should serve the static files.
21186 @item @code{getmail-retriever-config}
21187 The getmail-retriever-configuration record value to use with
21188 Patchwork. Getmail will be configured with this value, the messages will be
21189 delivered to Patchwork.
21194 @deftp {Data Type} patchwork-settings-module
21195 Data type representing a settings module for Patchwork. Some of these
21196 settings relate directly to Patchwork, but others relate to Django, the web
21197 framework used by Patchwork, or the Django Rest Framework library. This type
21198 has the following parameters:
21201 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
21202 The database connection settings used for Patchwork. See the
21203 @code{<patchwork-database-configuration>} record type for more information.
21205 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
21206 Patchwork, as a Django web application uses a secret key for cryptographically
21207 signing values. This file should contain a unique unpredictable value.
21209 If this file does not exist, it will be created and populated with a random
21210 value by the patchwork-setup shepherd service.
21212 This setting relates to Django.
21214 @item @code{allowed-hosts}
21215 A list of valid hosts for this Patchwork service. This should at least include
21216 the domain specified in the @code{<patchwork-configuration>} record.
21218 This is a Django setting.
21220 @item @code{default-from-email}
21221 The email address from which Patchwork should send email by default.
21223 This is a Patchwork setting.
21225 @item @code{static-url} (default: @code{#f})
21226 The URL to use when serving static assets. It can be part of a URL, or a full
21227 URL, but must end in a @code{/}.
21229 If the default value is used, the @code{static-path} value from the
21230 @code{<patchwork-configuration>} record will be used.
21232 This is a Django setting.
21234 @item @code{admins} (default: @code{'()})
21235 Email addresses to send the details of errors that occur. Each value should
21236 be a list containing two elements, the name and then the email address.
21238 This is a Django setting.
21240 @item @code{debug?} (default: @code{#f})
21241 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
21242 messages will be shown.
21244 This is a Django setting.
21246 @item @code{enable-rest-api?} (default: @code{#t})
21247 Whether to enable the Patchwork REST API.
21249 This is a Patchwork setting.
21251 @item @code{enable-xmlrpc?} (default: @code{#t})
21252 Whether to enable the XML RPC API.
21254 This is a Patchwork setting.
21256 @item @code{force-https-links?} (default: @code{#t})
21257 Whether to use HTTPS links on Patchwork pages.
21259 This is a Patchwork setting.
21261 @item @code{extra-settings} (default: @code{""})
21262 Extra code to place at the end of the Patchwork settings module.
21267 @deftp {Data Type} patchwork-database-configuration
21268 Data type representing the database configuration for Patchwork.
21271 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
21272 The database engine to use.
21274 @item @code{name} (default: @code{"patchwork"})
21275 The name of the database to use.
21277 @item @code{user} (default: @code{"httpd"})
21278 The user to connect to the database as.
21280 @item @code{password} (default: @code{""})
21281 The password to use when connecting to the database.
21283 @item @code{host} (default: @code{""})
21284 The host to make the database connection to.
21286 @item @code{port} (default: @code{""})
21287 The port on which to connect to the database.
21292 @subsubheading Mumi
21294 @cindex Mumi, Debbugs Web interface
21295 @cindex Debbugs, Mumi Web interface
21296 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
21297 Web interface to the Debbugs bug tracker, by default for
21298 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
21299 but it also fetches and indexes mail retrieved from Debbugs.
21301 @defvr {Scheme Variable} mumi-service-type
21302 This is the service type for Mumi.
21305 @deftp {Data Type} mumi-configuration
21306 Data type representing the Mumi service configuration. This type has the
21310 @item @code{mumi} (default: @code{mumi})
21311 The Mumi package to use.
21313 @item @code{mailer?} (default: @code{#true})
21314 Whether to enable or disable the mailer component.
21316 @item @code{mumi-configuration-sender}
21317 The email address used as the sender for comments.
21319 @item @code{mumi-configuration-smtp}
21320 A URI to configure the SMTP settings for Mailutils. This could be
21321 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
21322 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
21323 mailutils, GNU@tie{}Mailutils}.
21329 @subsubheading FastCGI
21332 FastCGI is an interface between the front-end and the back-end of a web
21333 service. It is a somewhat legacy facility; new web services should
21334 generally just talk HTTP between the front-end and the back-end.
21335 However there are a number of back-end services such as PHP or the
21336 optimized HTTP Git repository access that use FastCGI, so we have
21337 support for it in Guix.
21339 To use FastCGI, you configure the front-end web server (e.g., nginx) to
21340 dispatch some subset of its requests to the fastcgi backend, which
21341 listens on a local TCP or UNIX socket. There is an intermediary
21342 @code{fcgiwrap} program that sits between the actual backend process and
21343 the web server. The front-end indicates which backend program to run,
21344 passing that information to the @code{fcgiwrap} process.
21346 @defvr {Scheme Variable} fcgiwrap-service-type
21347 A service type for the @code{fcgiwrap} FastCGI proxy.
21350 @deftp {Data Type} fcgiwrap-configuration
21351 Data type representing the configuration of the @code{fcgiwrap} service.
21352 This type has the following parameters:
21354 @item @code{package} (default: @code{fcgiwrap})
21355 The fcgiwrap package to use.
21357 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
21358 The socket on which the @code{fcgiwrap} process should listen, as a
21359 string. Valid @var{socket} values include
21360 @code{unix:@var{/path/to/unix/socket}},
21361 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
21362 @code{tcp6:[@var{ipv6_addr}]:port}.
21364 @item @code{user} (default: @code{fcgiwrap})
21365 @itemx @code{group} (default: @code{fcgiwrap})
21366 The user and group names, as strings, under which to run the
21367 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
21368 the user asks for the specific user or group names @code{fcgiwrap} that
21369 the corresponding user and/or group is present on the system.
21371 It is possible to configure a FastCGI-backed web service to pass HTTP
21372 authentication information from the front-end to the back-end, and to
21373 allow @code{fcgiwrap} to run the back-end process as a corresponding
21374 local user. To enable this capability on the back-end, run
21375 @code{fcgiwrap} as the @code{root} user and group. Note that this
21376 capability also has to be configured on the front-end as well.
21381 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
21382 with some additional features useful for sites of any size.
21384 These features include:
21386 @item Adaptive process spawning
21387 @item Basic statistics (similar to Apache's mod_status)
21388 @item Advanced process management with graceful stop/start
21389 @item Ability to start workers with different uid/gid/chroot/environment
21390 and different php.ini (replaces safe_mode)
21391 @item Stdout & stderr logging
21392 @item Emergency restart in case of accidental opcode cache destruction
21393 @item Accelerated upload support
21394 @item Support for a "slowlog"
21395 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
21396 a special function to finish request & flush all data while continuing to do
21397 something time-consuming (video converting, stats processing, etc.)
21399 ...@: and much more.
21401 @defvr {Scheme Variable} php-fpm-service-type
21402 A Service type for @code{php-fpm}.
21405 @deftp {Data Type} php-fpm-configuration
21406 Data Type for php-fpm service configuration.
21408 @item @code{php} (default: @code{php})
21409 The php package to use.
21410 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
21411 The address on which to accept FastCGI requests. Valid syntaxes are:
21413 @item @code{"ip.add.re.ss:port"}
21414 Listen on a TCP socket to a specific address on a specific port.
21415 @item @code{"port"}
21416 Listen on a TCP socket to all addresses on a specific port.
21417 @item @code{"/path/to/unix/socket"}
21418 Listen on a unix socket.
21421 @item @code{user} (default: @code{php-fpm})
21422 User who will own the php worker processes.
21423 @item @code{group} (default: @code{php-fpm})
21424 Group of the worker processes.
21425 @item @code{socket-user} (default: @code{php-fpm})
21426 User who can speak to the php-fpm socket.
21427 @item @code{socket-group} (default: @code{nginx})
21428 Group that can speak to the php-fpm socket.
21429 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
21430 The process id of the php-fpm process is written to this file
21431 once the service has started.
21432 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
21433 Log for the php-fpm master process.
21434 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
21435 Detailed settings for the php-fpm process manager.
21438 @item @code{<php-fpm-dynamic-process-manager-configuration>}
21439 @item @code{<php-fpm-static-process-manager-configuration>}
21440 @item @code{<php-fpm-on-demand-process-manager-configuration>}
21442 @item @code{display-errors} (default @code{#f})
21443 Determines whether php errors and warning should be sent to clients
21444 and displayed in their browsers.
21445 This is useful for local php development, but a security risk for public sites,
21446 as error messages can reveal passwords and personal data.
21447 @item @code{timezone} (default @code{#f})
21448 Specifies @code{php_admin_value[date.timezone]} parameter.
21449 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
21450 This file will log the @code{stderr} outputs of php worker processes.
21451 Can be set to @code{#f} to disable logging.
21452 @item @code{file} (default @code{#f})
21453 An optional override of the whole configuration.
21454 You can use the @code{mixed-text-file} function or an absolute filepath for it.
21458 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
21459 Data Type for the @code{dynamic} php-fpm process manager. With the
21460 @code{dynamic} process manager, spare worker processes are kept around
21461 based on it's configured limits.
21463 @item @code{max-children} (default: @code{5})
21464 Maximum of worker processes.
21465 @item @code{start-servers} (default: @code{2})
21466 How many worker processes should be started on start-up.
21467 @item @code{min-spare-servers} (default: @code{1})
21468 How many spare worker processes should be kept around at minimum.
21469 @item @code{max-spare-servers} (default: @code{3})
21470 How many spare worker processes should be kept around at maximum.
21474 @deftp {Data type} php-fpm-static-process-manager-configuration
21475 Data Type for the @code{static} php-fpm process manager. With the
21476 @code{static} process manager, an unchanging number of worker processes
21479 @item @code{max-children} (default: @code{5})
21480 Maximum of worker processes.
21484 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
21485 Data Type for the @code{on-demand} php-fpm process manager. With the
21486 @code{on-demand} process manager, worker processes are only created as
21489 @item @code{max-children} (default: @code{5})
21490 Maximum of worker processes.
21491 @item @code{process-idle-timeout} (default: @code{10})
21492 The time in seconds after which a process with no requests is killed.
21497 @deffn {Scheme Procedure} nginx-php-location @
21498 [#:nginx-package nginx] @
21499 [socket (string-append "/var/run/php" @
21500 (version-major (package-version php)) @
21502 A helper function to quickly add php to an @code{nginx-server-configuration}.
21505 A simple services setup for nginx with php can look like this:
21507 (services (cons* (service dhcp-client-service-type)
21508 (service php-fpm-service-type)
21509 (service nginx-service-type
21510 (nginx-server-configuration
21511 (server-name '("example.com"))
21512 (root "/srv/http/")
21514 (list (nginx-php-location)))
21516 (ssl-certificate #f)
21517 (ssl-certificate-key #f)))
21521 @cindex cat-avatar-generator
21522 The cat avatar generator is a simple service to demonstrate the use of php-fpm
21523 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
21524 the hash of a user's email address.
21526 @deffn {Scheme Procedure} cat-avatar-generator-service @
21527 [#:cache-dir "/var/cache/cat-avatar-generator"] @
21528 [#:package cat-avatar-generator] @
21529 [#:configuration (nginx-server-configuration)]
21530 Returns an nginx-server-configuration that inherits @code{configuration}. It
21531 extends the nginx configuration to add a server block that serves @code{package},
21532 a version of cat-avatar-generator. During execution, cat-avatar-generator will
21533 be able to use @code{cache-dir} as its cache directory.
21536 A simple setup for cat-avatar-generator can look like this:
21538 (services (cons* (cat-avatar-generator-service
21540 (nginx-server-configuration
21541 (server-name '("example.com"))))
21546 @subsubheading Hpcguix-web
21548 @cindex hpcguix-web
21549 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
21550 program is a customizable web interface to browse Guix packages,
21551 initially designed for users of high-performance computing (HPC)
21554 @defvr {Scheme Variable} hpcguix-web-service-type
21555 The service type for @code{hpcguix-web}.
21558 @deftp {Data Type} hpcguix-web-configuration
21559 Data type for the hpcguix-web service configuration.
21563 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
21564 configuration. The main items available in this spec are:
21567 @item @code{title-prefix} (default: @code{"hpcguix | "})
21568 The page title prefix.
21570 @item @code{guix-command} (default: @code{"guix"})
21571 The @command{guix} command.
21573 @item @code{package-filter-proc} (default: @code{(const #t)})
21574 A procedure specifying how to filter packages that are displayed.
21576 @item @code{package-page-extension-proc} (default: @code{(const '())})
21577 Extension package for @code{hpcguix-web}.
21579 @item @code{menu} (default: @code{'()})
21580 Additional entry in page @code{menu}.
21582 @item @code{channels} (default: @code{%default-channels})
21583 List of channels from which the package list is built (@pxref{Channels}).
21585 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
21586 The expiration time, in seconds, after which the package list is rebuilt from
21587 the latest instances of the given channels.
21590 See the hpcguix-web repository for a
21591 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
21594 @item @code{package} (default: @code{hpcguix-web})
21595 The hpcguix-web package to use.
21599 A typical hpcguix-web service declaration looks like this:
21602 (service hpcguix-web-service-type
21603 (hpcguix-web-configuration
21605 #~(define site-config
21606 (hpcweb-configuration
21607 (title-prefix "Guix-HPC - ")
21608 (menu '(("/about" "ABOUT"))))))))
21612 The hpcguix-web service periodically updates the package list it publishes by
21613 pulling channels from Git. To that end, it needs to access X.509 certificates
21614 so that it can authenticate Git servers when communicating over HTTPS, and it
21615 assumes that @file{/etc/ssl/certs} contains those certificates.
21617 Thus, make sure to add @code{nss-certs} or another certificate package to the
21618 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
21619 more information on X.509 certificates.
21622 @node Certificate Services
21623 @subsection Certificate Services
21626 @cindex HTTP, HTTPS
21627 @cindex Let's Encrypt
21628 @cindex TLS certificates
21629 The @code{(gnu services certbot)} module provides a service to
21630 automatically obtain a valid TLS certificate from the Let's Encrypt
21631 certificate authority. These certificates can then be used to serve
21632 content securely over HTTPS or other TLS-based protocols, with the
21633 knowledge that the client will be able to verify the server's
21636 @url{https://letsencrypt.org/, Let's Encrypt} provides the
21637 @code{certbot} tool to automate the certification process. This tool
21638 first securely generates a key on the server. It then makes a request
21639 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
21640 checks that the request originates from the host in question by using a
21641 challenge-response protocol, requiring the server to provide its
21642 response over HTTP. If that protocol completes successfully, the CA
21643 signs the key, resulting in a certificate. That certificate is valid
21644 for a limited period of time, and therefore to continue to provide TLS
21645 services, the server needs to periodically ask the CA to renew its
21648 The certbot service automates this process: the initial key
21649 generation, the initial certification request to the Let's Encrypt
21650 service, the web server challenge/response integration, writing the
21651 certificate to disk, the automated periodic renewals, and the deployment
21652 tasks associated with the renewal (e.g.@: reloading services, copying keys
21653 with different permissions).
21655 Certbot is run twice a day, at a random minute within the hour. It
21656 won't do anything until your certificates are due for renewal or
21657 revoked, but running it regularly would give your service a chance of
21658 staying online in case a Let's Encrypt-initiated revocation happened for
21661 By using this service, you agree to the ACME Subscriber Agreement, which
21662 can be found there:
21663 @url{https://acme-v01.api.letsencrypt.org/directory}.
21665 @defvr {Scheme Variable} certbot-service-type
21666 A service type for the @code{certbot} Let's Encrypt client. Its value
21667 must be a @code{certbot-configuration} record as in this example:
21670 (define %nginx-deploy-hook
21672 "nginx-deploy-hook"
21673 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
21674 (kill pid SIGHUP))))
21676 (service certbot-service-type
21677 (certbot-configuration
21678 (email "foo@@example.net")
21681 (certificate-configuration
21682 (domains '("example.net" "www.example.net"))
21683 (deploy-hook %nginx-deploy-hook))
21684 (certificate-configuration
21685 (domains '("bar.example.net")))))))
21688 See below for details about @code{certbot-configuration}.
21691 @deftp {Data Type} certbot-configuration
21692 Data type representing the configuration of the @code{certbot} service.
21693 This type has the following parameters:
21696 @item @code{package} (default: @code{certbot})
21697 The certbot package to use.
21699 @item @code{webroot} (default: @code{/var/www})
21700 The directory from which to serve the Let's Encrypt challenge/response
21703 @item @code{certificates} (default: @code{()})
21704 A list of @code{certificates-configuration}s for which to generate
21705 certificates and request signatures. Each certificate has a @code{name}
21706 and several @code{domains}.
21709 Mandatory email used for registration, recovery contact, and important
21710 account notifications.
21712 @item @code{server} (default: @code{#f})
21713 Optional URL of ACME server. Setting this overrides certbot's default,
21714 which is the Let's Encrypt server.
21716 @item @code{rsa-key-size} (default: @code{2048})
21717 Size of the RSA key.
21719 @item @code{default-location} (default: @i{see below})
21720 The default @code{nginx-location-configuration}. Because @code{certbot}
21721 needs to be able to serve challenges and responses, it needs to be able
21722 to run a web server. It does so by extending the @code{nginx} web
21723 service with an @code{nginx-server-configuration} listening on the
21724 @var{domains} on port 80, and which has a
21725 @code{nginx-location-configuration} for the @code{/.well-known/} URI
21726 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
21727 these nginx configuration data types.
21729 Requests to other URL paths will be matched by the
21730 @code{default-location}, which if present is added to all
21731 @code{nginx-server-configuration}s.
21733 By default, the @code{default-location} will issue a redirect from
21734 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
21735 you to define what to serve on your site via @code{https}.
21737 Pass @code{#f} to not issue a default location.
21741 @deftp {Data Type} certificate-configuration
21742 Data type representing the configuration of a certificate.
21743 This type has the following parameters:
21746 @item @code{name} (default: @i{see below})
21747 This name is used by Certbot for housekeeping and in file paths; it
21748 doesn't affect the content of the certificate itself. To see
21749 certificate names, run @code{certbot certificates}.
21751 Its default is the first provided domain.
21753 @item @code{domains} (default: @code{()})
21754 The first domain provided will be the subject CN of the certificate, and
21755 all domains will be Subject Alternative Names on the certificate.
21757 @item @code{challenge} (default: @code{#f})
21758 The challenge type that has to be run by certbot. If @code{#f} is specified,
21759 default to the HTTP challenge. If a value is specified, defaults to the
21760 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
21761 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
21762 and gives Let's Encrypt permission to log the public IP address of the
21763 requesting machine.
21765 @item @code{authentication-hook} (default: @code{#f})
21766 Command to be run in a shell once for each certificate challenge to be
21767 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
21768 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
21769 contains the validation string and @code{$CERTBOT_TOKEN} contains the
21770 file name of the resource requested when performing an HTTP-01 challenge.
21772 @item @code{cleanup-hook} (default: @code{#f})
21773 Command to be run in a shell once for each certificate challenge that
21774 have been answered by the @code{auth-hook}. For this command, the shell
21775 variables available in the @code{auth-hook} script are still available, and
21776 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
21777 of the @code{auth-hook} script.
21779 @item @code{deploy-hook} (default: @code{#f})
21780 Command to be run in a shell once for each successfully issued
21781 certificate. For this command, the shell variable
21782 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
21783 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
21784 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
21785 contain a space-delimited list of renewed certificate domains (for
21786 example, @samp{"example.com www.example.com"}.
21791 For each @code{certificate-configuration}, the certificate is saved to
21792 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
21793 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
21795 @subsection DNS Services
21796 @cindex DNS (domain name system)
21797 @cindex domain name system (DNS)
21799 The @code{(gnu services dns)} module provides services related to the
21800 @dfn{domain name system} (DNS). It provides a server service for hosting
21801 an @emph{authoritative} DNS server for multiple zones, slave or master.
21802 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
21803 caching and forwarding DNS server for the LAN, which uses
21804 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
21806 @subsubheading Knot Service
21808 An example configuration of an authoritative server for two zones, one master
21812 (define-zone-entries example.org.zone
21813 ;; Name TTL Class Type Data
21814 ("@@" "" "IN" "A" "127.0.0.1")
21815 ("@@" "" "IN" "NS" "ns")
21816 ("ns" "" "IN" "A" "127.0.0.1"))
21818 (define master-zone
21819 (knot-zone-configuration
21820 (domain "example.org")
21822 (origin "example.org")
21823 (entries example.org.zone)))))
21826 (knot-zone-configuration
21827 (domain "plop.org")
21828 (dnssec-policy "default")
21829 (master (list "plop-master"))))
21831 (define plop-master
21832 (knot-remote-configuration
21834 (address (list "208.76.58.171"))))
21838 (services (cons* (service knot-service-type
21839 (knot-configuration
21840 (remotes (list plop-master))
21841 (zones (list master-zone slave-zone))))
21846 @deffn {Scheme Variable} knot-service-type
21847 This is the type for the Knot DNS server.
21849 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
21850 zones, that is to say domain names you would buy from a registrar. This server
21851 is not a resolver, meaning that it can only resolve names for which it is
21852 authoritative. This server can be configured to serve zones as a master server
21853 or a slave server as a per-zone basis. Slave zones will get their data from
21854 masters, and will serve it as an authoritative server. From the point of view
21855 of a resolver, there is no difference between master and slave.
21857 The following data types are used to configure the Knot DNS server:
21860 @deftp {Data Type} knot-key-configuration
21861 Data type representing a key.
21862 This type has the following parameters:
21865 @item @code{id} (default: @code{""})
21866 An identifier for other configuration fields to refer to this key. IDs must
21867 be unique and must not be empty.
21869 @item @code{algorithm} (default: @code{#f})
21870 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
21871 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
21872 and @code{'hmac-sha512}.
21874 @item @code{secret} (default: @code{""})
21875 The secret key itself.
21880 @deftp {Data Type} knot-acl-configuration
21881 Data type representing an Access Control List (ACL) configuration.
21882 This type has the following parameters:
21885 @item @code{id} (default: @code{""})
21886 An identifier for ether configuration fields to refer to this key. IDs must be
21887 unique and must not be empty.
21889 @item @code{address} (default: @code{'()})
21890 An ordered list of IP addresses, network subnets, or network ranges represented
21891 with strings. The query must match one of them. Empty value means that
21892 address match is not required.
21894 @item @code{key} (default: @code{'()})
21895 An ordered list of references to keys represented with strings. The string
21896 must match a key ID defined in a @code{knot-key-configuration}. No key means
21897 that a key is not require to match that ACL.
21899 @item @code{action} (default: @code{'()})
21900 An ordered list of actions that are permitted or forbidden by this ACL. Possible
21901 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
21902 and @code{'update}.
21904 @item @code{deny?} (default: @code{#f})
21905 When true, the ACL defines restrictions. Listed actions are forbidden. When
21906 false, listed actions are allowed.
21911 @deftp {Data Type} zone-entry
21912 Data type representing a record entry in a zone file.
21913 This type has the following parameters:
21916 @item @code{name} (default: @code{"@@"})
21917 The name of the record. @code{"@@"} refers to the origin of the zone. Names
21918 are relative to the origin of the zone. For example, in the @code{example.org}
21919 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
21920 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
21921 refers to @code{ns.example.org}.
21923 @item @code{ttl} (default: @code{""})
21924 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
21926 @item @code{class} (default: @code{"IN"})
21927 The class of the record. Knot currently supports only @code{"IN"} and
21928 partially @code{"CH"}.
21930 @item @code{type} (default: @code{"A"})
21931 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
21932 address), NS (Name Server) and MX (Mail eXchange). Many other types are
21935 @item @code{data} (default: @code{""})
21936 The data contained in the record. For instance an IP address associated with
21937 an A record, or a domain name associated with an NS record. Remember that
21938 domain names are relative to the origin unless they end with a dot.
21943 @deftp {Data Type} zone-file
21944 Data type representing the content of a zone file.
21945 This type has the following parameters:
21948 @item @code{entries} (default: @code{'()})
21949 The list of entries. The SOA record is taken care of, so you don't need to
21950 put it in the list of entries. This list should probably contain an entry
21951 for your primary authoritative DNS server. Other than using a list of entries
21952 directly, you can use @code{define-zone-entries} to define a object containing
21953 the list of entries more easily, that you can later pass to the @code{entries}
21954 field of the @code{zone-file}.
21956 @item @code{origin} (default: @code{""})
21957 The name of your zone. This parameter cannot be empty.
21959 @item @code{ns} (default: @code{"ns"})
21960 The domain of your primary authoritative DNS server. The name is relative to
21961 the origin, unless it ends with a dot. It is mandatory that this primary
21962 DNS server corresponds to an NS record in the zone and that it is associated
21963 to an IP address in the list of entries.
21965 @item @code{mail} (default: @code{"hostmaster"})
21966 An email address people can contact you at, as the owner of the zone. This
21967 is translated as @code{<mail>@@<origin>}.
21969 @item @code{serial} (default: @code{1})
21970 The serial number of the zone. As this is used to keep track of changes by
21971 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
21972 Always increment it when you make a change in your zone.
21974 @item @code{refresh} (default: @code{(* 2 24 3600)})
21975 The frequency at which slaves will do a zone transfer. This value is a number
21976 of seconds. It can be computed by multiplications or with
21977 @code{(string->duration)}.
21979 @item @code{retry} (default: @code{(* 15 60)})
21980 The period after which a slave will retry to contact its master when it fails
21981 to do so a first time.
21983 @item @code{expiry} (default: @code{(* 14 24 3600)})
21984 Default TTL of records. Existing records are considered correct for at most
21985 this amount of time. After this period, resolvers will invalidate their cache
21986 and check again that it still exists.
21988 @item @code{nx} (default: @code{3600})
21989 Default TTL of inexistant records. This delay is usually short because you want
21990 your new domains to reach everyone quickly.
21995 @deftp {Data Type} knot-remote-configuration
21996 Data type representing a remote configuration.
21997 This type has the following parameters:
22000 @item @code{id} (default: @code{""})
22001 An identifier for other configuration fields to refer to this remote. IDs must
22002 be unique and must not be empty.
22004 @item @code{address} (default: @code{'()})
22005 An ordered list of destination IP addresses. Addresses are tried in sequence.
22006 An optional port can be given with the @@ separator. For instance:
22007 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
22009 @item @code{via} (default: @code{'()})
22010 An ordered list of source IP addresses. An empty list will have Knot choose
22011 an appropriate source IP. An optional port can be given with the @@ separator.
22012 The default is to choose at random.
22014 @item @code{key} (default: @code{#f})
22015 A reference to a key, that is a string containing the identifier of a key
22016 defined in a @code{knot-key-configuration} field.
22021 @deftp {Data Type} knot-keystore-configuration
22022 Data type representing a keystore to hold dnssec keys.
22023 This type has the following parameters:
22026 @item @code{id} (default: @code{""})
22027 The id of the keystore. It must not be empty.
22029 @item @code{backend} (default: @code{'pem})
22030 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
22032 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
22033 The configuration string of the backend. An example for the PKCS#11 is:
22034 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
22035 For the pem backend, the string represents a path in the file system.
22040 @deftp {Data Type} knot-policy-configuration
22041 Data type representing a dnssec policy. Knot DNS is able to automatically
22042 sign your zones. It can either generate and manage your keys automatically or
22043 use keys that you generate.
22045 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
22046 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
22047 zone. In order to be trusted, the KSK needs to be present in the parent zone
22048 (usually a top-level domain). If your registrar supports dnssec, you will
22049 have to send them your KSK's hash so they can add a DS record in their zone.
22050 This is not automated and need to be done each time you change your KSK.
22052 The policy also defines the lifetime of keys. Usually, ZSK can be changed
22053 easily and use weaker cryptographic functions (they use lower parameters) in
22054 order to sign records quickly, so they are changed often. The KSK however
22055 requires manual interaction with the registrar, so they are changed less often
22056 and use stronger parameters because they sign only one record.
22058 This type has the following parameters:
22061 @item @code{id} (default: @code{""})
22062 The id of the policy. It must not be empty.
22064 @item @code{keystore} (default: @code{"default"})
22065 A reference to a keystore, that is a string containing the identifier of a
22066 keystore defined in a @code{knot-keystore-configuration} field. The
22067 @code{"default"} identifier means the default keystore (a kasp database that
22068 was setup by this service).
22070 @item @code{manual?} (default: @code{#f})
22071 Whether the key management is manual or automatic.
22073 @item @code{single-type-signing?} (default: @code{#f})
22074 When @code{#t}, use the Single-Type Signing Scheme.
22076 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
22077 An algorithm of signing keys and issued signatures.
22079 @item @code{ksk-size} (default: @code{256})
22080 The length of the KSK. Note that this value is correct for the default
22081 algorithm, but would be unsecure for other algorithms.
22083 @item @code{zsk-size} (default: @code{256})
22084 The length of the ZSK. Note that this value is correct for the default
22085 algorithm, but would be unsecure for other algorithms.
22087 @item @code{dnskey-ttl} (default: @code{'default})
22088 The TTL value for DNSKEY records added into zone apex. The special
22089 @code{'default} value means same as the zone SOA TTL.
22091 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
22092 The period between ZSK publication and the next rollover initiation.
22094 @item @code{propagation-delay} (default: @code{(* 24 3600)})
22095 An extra delay added for each key rollover step. This value should be high
22096 enough to cover propagation of data from the master server to all slaves.
22098 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
22099 A validity period of newly issued signatures.
22101 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
22102 A period how long before a signature expiration the signature will be refreshed.
22104 @item @code{nsec3?} (default: @code{#f})
22105 When @code{#t}, NSEC3 will be used instead of NSEC.
22107 @item @code{nsec3-iterations} (default: @code{5})
22108 The number of additional times the hashing is performed.
22110 @item @code{nsec3-salt-length} (default: @code{8})
22111 The length of a salt field in octets, which is appended to the original owner
22112 name before hashing.
22114 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
22115 The validity period of newly issued salt field.
22120 @deftp {Data Type} knot-zone-configuration
22121 Data type representing a zone served by Knot.
22122 This type has the following parameters:
22125 @item @code{domain} (default: @code{""})
22126 The domain served by this configuration. It must not be empty.
22128 @item @code{file} (default: @code{""})
22129 The file where this zone is saved. This parameter is ignored by master zones.
22130 Empty means default location that depends on the domain name.
22132 @item @code{zone} (default: @code{(zone-file)})
22133 The content of the zone file. This parameter is ignored by slave zones. It
22134 must contain a zone-file record.
22136 @item @code{master} (default: @code{'()})
22137 A list of master remotes. When empty, this zone is a master. When set, this
22138 zone is a slave. This is a list of remotes identifiers.
22140 @item @code{ddns-master} (default: @code{#f})
22141 The main master. When empty, it defaults to the first master in the list of
22144 @item @code{notify} (default: @code{'()})
22145 A list of slave remote identifiers.
22147 @item @code{acl} (default: @code{'()})
22148 A list of acl identifiers.
22150 @item @code{semantic-checks?} (default: @code{#f})
22151 When set, this adds more semantic checks to the zone.
22153 @item @code{disable-any?} (default: @code{#f})
22154 When set, this forbids queries of the ANY type.
22156 @item @code{zonefile-sync} (default: @code{0})
22157 The delay between a modification in memory and on disk. 0 means immediate
22160 @item @code{zonefile-load} (default: @code{#f})
22161 The way the zone file contents are applied during zone load. Possible values
22165 @item @code{#f} for using the default value from Knot,
22166 @item @code{'none} for not using the zone file at all,
22167 @item @code{'difference} for computing the difference between already available
22168 contents and zone contents and applying it to the current zone contents,
22169 @item @code{'difference-no-serial} for the same as @code{'difference}, but
22170 ignoring the SOA serial in the zone file, while the server takes care of it
22172 @item @code{'whole} for loading zone contents from the zone file.
22175 @item @code{journal-content} (default: @code{#f})
22176 The way the journal is used to store zone and its changes. Possible values
22177 are @code{'none} to not use it at all, @code{'changes} to store changes and
22178 @code{'all} to store contents. @code{#f} does not set this option, so the
22179 default value from Knot is used.
22181 @item @code{max-journal-usage} (default: @code{#f})
22182 The maximum size for the journal on disk. @code{#f} does not set this option,
22183 so the default value from Knot is used.
22185 @item @code{max-journal-depth} (default: @code{#f})
22186 The maximum size of the history. @code{#f} does not set this option, so the
22187 default value from Knot is used.
22189 @item @code{max-zone-size} (default: @code{#f})
22190 The maximum size of the zone file. This limit is enforced for incoming
22191 transfer and updates. @code{#f} does not set this option, so the default
22192 value from Knot is used.
22194 @item @code{dnssec-policy} (default: @code{#f})
22195 A reference to a @code{knot-policy-configuration} record, or the special
22196 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
22199 @item @code{serial-policy} (default: @code{'increment})
22200 A policy between @code{'increment} and @code{'unixtime}.
22205 @deftp {Data Type} knot-configuration
22206 Data type representing the Knot configuration.
22207 This type has the following parameters:
22210 @item @code{knot} (default: @code{knot})
22213 @item @code{run-directory} (default: @code{"/var/run/knot"})
22214 The run directory. This directory will be used for pid file and sockets.
22216 @item @code{includes} (default: @code{'()})
22217 A list of strings or file-like objects denoting other files that must be
22218 included at the top of the configuration file.
22220 @cindex secrets, Knot service
22221 This can be used to manage secrets out-of-band. For example, secret
22222 keys may be stored in an out-of-band file not managed by Guix, and
22223 thus not visible in @file{/gnu/store}---e.g., you could store secret
22224 key configuration in @file{/etc/knot/secrets.conf} and add this file
22225 to the @code{includes} list.
22227 One can generate a secret tsig key (for nsupdate and zone transfers with the
22228 keymgr command from the knot package. Note that the package is not automatically
22229 installed by the service. The following example shows how to generate a new
22233 keymgr -t mysecret > /etc/knot/secrets.conf
22234 chmod 600 /etc/knot/secrets.conf
22237 Also note that the generated key will be named @var{mysecret}, so it is the
22238 name that needs to be used in the @var{key} field of the
22239 @code{knot-acl-configuration} record and in other places that need to refer
22242 It can also be used to add configuration not supported by this interface.
22244 @item @code{listen-v4} (default: @code{"0.0.0.0"})
22245 An ip address on which to listen.
22247 @item @code{listen-v6} (default: @code{"::"})
22248 An ip address on which to listen.
22250 @item @code{listen-port} (default: @code{53})
22251 A port on which to listen.
22253 @item @code{keys} (default: @code{'()})
22254 The list of knot-key-configuration used by this configuration.
22256 @item @code{acls} (default: @code{'()})
22257 The list of knot-acl-configuration used by this configuration.
22259 @item @code{remotes} (default: @code{'()})
22260 The list of knot-remote-configuration used by this configuration.
22262 @item @code{zones} (default: @code{'()})
22263 The list of knot-zone-configuration used by this configuration.
22268 @subsubheading Knot Resolver Service
22270 @deffn {Scheme Variable} knot-resolver-service-type
22271 This this the type of the knot resolver service, whose value should be
22272 an @code{knot-resolver-configuration} object as in this example:
22275 (service knot-resolver-service-type
22276 (knot-resolver-configuration
22277 (kresd-config-file (plain-file "kresd.conf" "
22278 net.listen('192.168.0.1', 5353)
22279 user('knot-resolver', 'knot-resolver')
22280 modules = @{ 'hints > iterate', 'stats', 'predict' @}
22281 cache.size = 100 * MB
22285 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
22288 @deftp {Data Type} knot-resolver-configuration
22289 Data type representing the configuration of knot-resolver.
22292 @item @code{package} (default: @var{knot-resolver})
22293 Package object of the knot DNS resolver.
22295 @item @code{kresd-config-file} (default: %kresd.conf)
22296 File-like object of the kresd configuration file to use, by default it
22297 will listen on @code{127.0.0.1} and @code{::1}.
22299 @item @code{garbage-collection-interval} (default: 1000)
22300 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
22306 @subsubheading Dnsmasq Service
22308 @deffn {Scheme Variable} dnsmasq-service-type
22309 This is the type of the dnsmasq service, whose value should be an
22310 @code{dnsmasq-configuration} object as in this example:
22313 (service dnsmasq-service-type
22314 (dnsmasq-configuration
22316 (servers '("192.168.1.1"))))
22320 @deftp {Data Type} dnsmasq-configuration
22321 Data type representing the configuration of dnsmasq.
22324 @item @code{package} (default: @var{dnsmasq})
22325 Package object of the dnsmasq server.
22327 @item @code{no-hosts?} (default: @code{#f})
22328 When true, don't read the hostnames in /etc/hosts.
22330 @item @code{port} (default: @code{53})
22331 The port to listen on. Setting this to zero completely disables DNS
22332 responses, leaving only DHCP and/or TFTP functions.
22334 @item @code{local-service?} (default: @code{#t})
22335 Accept DNS queries only from hosts whose address is on a local subnet,
22336 ie a subnet for which an interface exists on the server.
22338 @item @code{listen-addresses} (default: @code{'()})
22339 Listen on the given IP addresses.
22341 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
22342 The file to read the IP address of the upstream nameservers from.
22344 @item @code{no-resolv?} (default: @code{#f})
22345 When true, don't read @var{resolv-file}.
22347 @item @code{servers} (default: @code{'()})
22348 Specify IP address of upstream servers directly.
22350 @item @code{addresses} (default: @code{'()})
22351 For each entry, specify an IP address to return for any host in the
22352 given domains. Queries in the domains are never forwarded and always
22353 replied to with the specified IP address.
22355 This is useful for redirecting hosts locally, for example:
22358 (service dnsmasq-service-type
22359 (dnsmasq-configuration
22361 '(; Redirect to a local web-server.
22362 "/example.org/127.0.0.1"
22363 ; Redirect subdomain to a specific IP.
22364 "/subdomain.example.org/192.168.1.42"))))
22367 Note that rules in @file{/etc/hosts} take precedence over this.
22369 @item @code{cache-size} (default: @code{150})
22370 Set the size of dnsmasq's cache. Setting the cache size to zero
22373 @item @code{negative-cache?} (default: @code{#t})
22374 When false, disable negative caching.
22379 @subsubheading ddclient Service
22382 The ddclient service described below runs the ddclient daemon, which takes
22383 care of automatically updating DNS entries for service providers such as
22384 @uref{https://dyn.com/dns/, Dyn}.
22386 The following example show instantiates the service with its default
22390 (service ddclient-service-type)
22393 Note that ddclient needs to access credentials that are stored in a
22394 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
22395 @code{secret-file} below). You are expected to create this file manually, in
22396 an ``out-of-band'' fashion (you @emph{could} make this file part of the
22397 service configuration, for instance by using @code{plain-file}, but it will be
22398 world-readable @i{via} @file{/gnu/store}). See the examples in the
22399 @file{share/ddclient} directory of the @code{ddclient} package.
22401 @c %start of fragment
22403 Available @code{ddclient-configuration} fields are:
22405 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
22406 The ddclient package.
22410 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
22411 The period after which ddclient will retry to check IP and domain name.
22413 Defaults to @samp{300}.
22417 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
22418 Use syslog for the output.
22420 Defaults to @samp{#t}.
22424 @deftypevr {@code{ddclient-configuration} parameter} string mail
22427 Defaults to @samp{"root"}.
22431 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
22432 Mail failed update to user.
22434 Defaults to @samp{"root"}.
22438 @deftypevr {@code{ddclient-configuration} parameter} string pid
22439 The ddclient PID file.
22441 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
22445 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
22446 Enable SSL support.
22448 Defaults to @samp{#t}.
22452 @deftypevr {@code{ddclient-configuration} parameter} string user
22453 Specifies the user name or ID that is used when running ddclient
22456 Defaults to @samp{"ddclient"}.
22460 @deftypevr {@code{ddclient-configuration} parameter} string group
22461 Group of the user who will run the ddclient program.
22463 Defaults to @samp{"ddclient"}.
22467 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
22468 Secret file which will be appended to @file{ddclient.conf} file. This
22469 file contains credentials for use by ddclient. You are expected to
22470 create it manually.
22472 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
22476 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
22477 Extra options will be appended to @file{ddclient.conf} file.
22479 Defaults to @samp{()}.
22484 @c %end of fragment
22488 @subsection VPN Services
22489 @cindex VPN (virtual private network)
22490 @cindex virtual private network (VPN)
22492 The @code{(gnu services vpn)} module provides services related to
22493 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
22494 your machine to connect to a VPN, and a @emph{server} service for your machine
22495 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
22497 @deffn {Scheme Procedure} openvpn-client-service @
22498 [#:config (openvpn-client-configuration)]
22500 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
22503 @deffn {Scheme Procedure} openvpn-server-service @
22504 [#:config (openvpn-server-configuration)]
22506 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
22508 Both can be run simultaneously.
22511 @c %automatically generated documentation
22513 Available @code{openvpn-client-configuration} fields are:
22515 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
22516 The OpenVPN package.
22520 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
22521 The OpenVPN pid file.
22523 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22527 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
22528 The protocol (UDP or TCP) used to open a channel between clients and
22531 Defaults to @samp{udp}.
22535 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
22536 The device type used to represent the VPN connection.
22538 Defaults to @samp{tun}.
22542 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
22543 The certificate authority to check connections against.
22545 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22549 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
22550 The certificate of the machine the daemon is running on. It should be
22551 signed by the authority given in @code{ca}.
22553 Defaults to @samp{"/etc/openvpn/client.crt"}.
22557 @deftypevr {@code{openvpn-client-configuration} parameter} string key
22558 The key of the machine the daemon is running on. It must be the key whose
22559 certificate is @code{cert}.
22561 Defaults to @samp{"/etc/openvpn/client.key"}.
22565 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
22566 Whether to use the lzo compression algorithm.
22568 Defaults to @samp{#t}.
22572 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
22573 Don't re-read key files across SIGUSR1 or --ping-restart.
22575 Defaults to @samp{#t}.
22579 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
22580 Don't close and reopen TUN/TAP device or run up/down scripts across
22581 SIGUSR1 or --ping-restart restarts.
22583 Defaults to @samp{#t}.
22587 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
22588 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22589 poll/epoll/select prior to the write operation.
22591 Defaults to @samp{#f}.
22594 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
22597 Defaults to @samp{3}.
22601 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
22602 Add an additional layer of HMAC authentication on top of the TLS control
22603 channel to protect against DoS attacks.
22605 Defaults to @samp{#f}.
22609 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
22610 Authenticate with server using username/password. The option is a file
22611 containing username/password on 2 lines. Do not use a file-like object as it
22612 would be added to the store and readable by any user.
22614 Defaults to @samp{'disabled}.
22617 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
22618 Whether to check the server certificate has server usage extension.
22620 Defaults to @samp{#t}.
22624 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
22625 Bind to a specific local port number.
22627 Defaults to @samp{#f}.
22631 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
22632 Retry resolving server address.
22634 Defaults to @samp{#t}.
22638 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
22639 A list of remote servers to connect to.
22641 Defaults to @samp{()}.
22643 Available @code{openvpn-remote-configuration} fields are:
22645 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
22648 Defaults to @samp{"my-server"}.
22652 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
22653 Port number the server listens to.
22655 Defaults to @samp{1194}.
22660 @c %end of automatic openvpn-client documentation
22662 @c %automatically generated documentation
22664 Available @code{openvpn-server-configuration} fields are:
22666 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
22667 The OpenVPN package.
22671 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
22672 The OpenVPN pid file.
22674 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22678 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
22679 The protocol (UDP or TCP) used to open a channel between clients and
22682 Defaults to @samp{udp}.
22686 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
22687 The device type used to represent the VPN connection.
22689 Defaults to @samp{tun}.
22693 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
22694 The certificate authority to check connections against.
22696 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22700 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
22701 The certificate of the machine the daemon is running on. It should be
22702 signed by the authority given in @code{ca}.
22704 Defaults to @samp{"/etc/openvpn/client.crt"}.
22708 @deftypevr {@code{openvpn-server-configuration} parameter} string key
22709 The key of the machine the daemon is running on. It must be the key whose
22710 certificate is @code{cert}.
22712 Defaults to @samp{"/etc/openvpn/client.key"}.
22716 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
22717 Whether to use the lzo compression algorithm.
22719 Defaults to @samp{#t}.
22723 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
22724 Don't re-read key files across SIGUSR1 or --ping-restart.
22726 Defaults to @samp{#t}.
22730 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
22731 Don't close and reopen TUN/TAP device or run up/down scripts across
22732 SIGUSR1 or --ping-restart restarts.
22734 Defaults to @samp{#t}.
22738 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
22739 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22740 poll/epoll/select prior to the write operation.
22742 Defaults to @samp{#f}.
22745 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
22748 Defaults to @samp{3}.
22752 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
22753 Add an additional layer of HMAC authentication on top of the TLS control
22754 channel to protect against DoS attacks.
22756 Defaults to @samp{#f}.
22760 @deftypevr {@code{openvpn-server-configuration} parameter} number port
22761 Specifies the port number on which the server listens.
22763 Defaults to @samp{1194}.
22767 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
22768 An ip and mask specifying the subnet inside the virtual network.
22770 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
22774 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
22775 A CIDR notation specifying the IPv6 subnet inside the virtual network.
22777 Defaults to @samp{#f}.
22781 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
22782 The Diffie-Hellman parameters file.
22784 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
22788 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
22789 The file that records client IPs.
22791 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
22795 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
22796 When true, the server will act as a gateway for its clients.
22798 Defaults to @samp{#f}.
22802 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
22803 When true, clients are allowed to talk to each other inside the VPN.
22805 Defaults to @samp{#f}.
22809 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
22810 Causes ping-like messages to be sent back and forth over the link so
22811 that each side knows when the other side has gone down. @code{keepalive}
22812 requires a pair. The first element is the period of the ping sending,
22813 and the second element is the timeout before considering the other side
22818 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
22819 The maximum number of clients.
22821 Defaults to @samp{100}.
22825 @deftypevr {@code{openvpn-server-configuration} parameter} string status
22826 The status file. This file shows a small report on current connection.
22827 It is truncated and rewritten every minute.
22829 Defaults to @samp{"/var/run/openvpn/status"}.
22833 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
22834 The list of configuration for some clients.
22836 Defaults to @samp{()}.
22838 Available @code{openvpn-ccd-configuration} fields are:
22840 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
22843 Defaults to @samp{"client"}.
22847 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
22850 Defaults to @samp{#f}.
22854 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
22857 Defaults to @samp{#f}.
22864 @c %end of automatic openvpn-server documentation
22867 @node Network File System
22868 @subsection Network File System
22871 The @code{(gnu services nfs)} module provides the following services,
22872 which are most commonly used in relation to mounting or exporting
22873 directory trees as @dfn{network file systems} (NFS).
22875 While it is possible to use the individual components that together make
22876 up a Network File System service, we recommended to configure an NFS
22877 server with the @code{nfs-service-type}.
22879 @subsubheading NFS Service
22880 @cindex NFS, server
22882 The NFS service takes care of setting up all NFS component services,
22883 kernel configuration file systems, and installs configuration files in
22884 the locations that NFS expects.
22886 @defvr {Scheme Variable} nfs-service-type
22887 A service type for a complete NFS server.
22890 @deftp {Data Type} nfs-configuration
22891 This data type represents the configuration of the NFS service and all
22894 It has the following parameters:
22896 @item @code{nfs-utils} (default: @code{nfs-utils})
22897 The nfs-utils package to use.
22899 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
22900 If a list of string values is provided, the @command{rpc.nfsd} daemon
22901 will be limited to supporting the given versions of the NFS protocol.
22903 @item @code{exports} (default: @code{'()})
22904 This is a list of directories the NFS server should export. Each entry
22905 is a list consisting of two elements: a directory name and a string
22906 containing all options. This is an example in which the directory
22907 @file{/export} is served to all NFS clients as a read-only share:
22913 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
22916 @item @code{rpcmountd-port} (default: @code{#f})
22917 The network port that the @command{rpc.mountd} daemon should use.
22919 @item @code{rpcstatd-port} (default: @code{#f})
22920 The network port that the @command{rpc.statd} daemon should use.
22922 @item @code{rpcbind} (default: @code{rpcbind})
22923 The rpcbind package to use.
22925 @item @code{idmap-domain} (default: @code{"localdomain"})
22926 The local NFSv4 domain name.
22928 @item @code{nfsd-port} (default: @code{2049})
22929 The network port that the @command{nfsd} daemon should use.
22931 @item @code{nfsd-threads} (default: @code{8})
22932 The number of threads used by the @command{nfsd} daemon.
22934 @item @code{nfsd-tcp?} (default: @code{#t})
22935 Whether the @command{nfsd} daemon should listen on a TCP socket.
22937 @item @code{nfsd-udp?} (default: @code{#f})
22938 Whether the @command{nfsd} daemon should listen on a UDP socket.
22940 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22941 The directory where the pipefs file system is mounted.
22943 @item @code{debug} (default: @code{'()"})
22944 A list of subsystems for which debugging output should be enabled. This
22945 is a list of symbols. Any of these symbols are valid: @code{nfsd},
22946 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
22950 If you don't need a complete NFS service or prefer to build it yourself
22951 you can use the individual component services that are documented below.
22953 @subsubheading RPC Bind Service
22956 The RPC Bind service provides a facility to map program numbers into
22957 universal addresses.
22958 Many NFS related services use this facility. Hence it is automatically
22959 started when a dependent service starts.
22961 @defvr {Scheme Variable} rpcbind-service-type
22962 A service type for the RPC portmapper daemon.
22966 @deftp {Data Type} rpcbind-configuration
22967 Data type representing the configuration of the RPC Bind Service.
22968 This type has the following parameters:
22970 @item @code{rpcbind} (default: @code{rpcbind})
22971 The rpcbind package to use.
22973 @item @code{warm-start?} (default: @code{#t})
22974 If this parameter is @code{#t}, then the daemon will read a
22975 state file on startup thus reloading state information saved by a previous
22981 @subsubheading Pipefs Pseudo File System
22985 The pipefs file system is used to transfer NFS related data
22986 between the kernel and user space programs.
22988 @defvr {Scheme Variable} pipefs-service-type
22989 A service type for the pipefs pseudo file system.
22992 @deftp {Data Type} pipefs-configuration
22993 Data type representing the configuration of the pipefs pseudo file system service.
22994 This type has the following parameters:
22996 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22997 The directory to which the file system is to be attached.
23002 @subsubheading GSS Daemon Service
23005 @cindex global security system
23007 The @dfn{global security system} (GSS) daemon provides strong security for RPC
23009 Before exchanging RPC requests an RPC client must establish a security
23010 context. Typically this is done using the Kerberos command @command{kinit}
23011 or automatically at login time using PAM services (@pxref{Kerberos Services}).
23013 @defvr {Scheme Variable} gss-service-type
23014 A service type for the Global Security System (GSS) daemon.
23017 @deftp {Data Type} gss-configuration
23018 Data type representing the configuration of the GSS daemon service.
23019 This type has the following parameters:
23021 @item @code{nfs-utils} (default: @code{nfs-utils})
23022 The package in which the @command{rpc.gssd} command is to be found.
23024 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23025 The directory where the pipefs file system is mounted.
23031 @subsubheading IDMAP Daemon Service
23033 @cindex name mapper
23035 The idmap daemon service provides mapping between user IDs and user names.
23036 Typically it is required in order to access file systems mounted via NFSv4.
23038 @defvr {Scheme Variable} idmap-service-type
23039 A service type for the Identity Mapper (IDMAP) daemon.
23042 @deftp {Data Type} idmap-configuration
23043 Data type representing the configuration of the IDMAP daemon service.
23044 This type has the following parameters:
23046 @item @code{nfs-utils} (default: @code{nfs-utils})
23047 The package in which the @command{rpc.idmapd} command is to be found.
23049 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23050 The directory where the pipefs file system is mounted.
23052 @item @code{domain} (default: @code{#f})
23053 The local NFSv4 domain name.
23054 This must be a string or @code{#f}.
23055 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
23057 @item @code{verbosity} (default: @code{0})
23058 The verbosity level of the daemon.
23063 @node Continuous Integration
23064 @subsection Continuous Integration
23066 @cindex continuous integration
23067 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
23068 continuous integration tool for Guix. It can be used both for development and
23069 for providing substitutes to others (@pxref{Substitutes}).
23071 The @code{(gnu services cuirass)} module provides the following service.
23073 @defvr {Scheme Procedure} cuirass-service-type
23074 The type of the Cuirass service. Its value must be a
23075 @code{cuirass-configuration} object, as described below.
23078 To add build jobs, you have to set the @code{specifications} field of the
23079 configuration. Here is an example of a service that polls the Guix repository
23080 and builds the packages from a manifest. Some of the packages are defined in
23081 the @code{"custom-packages"} input, which is the equivalent of
23082 @env{GUIX_PACKAGE_PATH}.
23085 (define %cuirass-specs
23087 '((#:name . "my-manifest")
23088 (#:load-path-inputs . ("guix"))
23089 (#:package-path-inputs . ("custom-packages"))
23090 (#:proc-input . "guix")
23091 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
23092 (#:proc . cuirass-jobs)
23093 (#:proc-args . ((subset . "manifests")
23094 (systems . ("x86_64-linux"))
23095 (manifests . (("config" . "guix/manifest.scm")))))
23096 (#:inputs . (((#:name . "guix")
23097 (#:url . "git://git.savannah.gnu.org/guix.git")
23098 (#:load-path . ".")
23099 (#:branch . "master")
23100 (#:no-compile? . #t))
23101 ((#:name . "config")
23102 (#:url . "https://git.example.org/config.git")
23103 (#:load-path . ".")
23104 (#:branch . "master")
23105 (#:no-compile? . #t))
23106 ((#:name . "custom-packages")
23107 (#:url . "https://git.example.org/custom-packages.git")
23108 (#:load-path . ".")
23109 (#:branch . "master")
23110 (#:no-compile? . #t)))))))
23112 (service cuirass-service-type
23113 (cuirass-configuration
23114 (specifications %cuirass-specs)))
23117 While information related to build jobs is located directly in the
23118 specifications, global settings for the @command{cuirass} process are
23119 accessible in other @code{cuirass-configuration} fields.
23121 @deftp {Data Type} cuirass-configuration
23122 Data type representing the configuration of Cuirass.
23125 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
23126 Location of the log file.
23128 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
23129 Location of the log file used by the web interface.
23131 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
23132 Location of the repository cache.
23134 @item @code{user} (default: @code{"cuirass"})
23135 Owner of the @code{cuirass} process.
23137 @item @code{group} (default: @code{"cuirass"})
23138 Owner's group of the @code{cuirass} process.
23140 @item @code{interval} (default: @code{60})
23141 Number of seconds between the poll of the repositories followed by the
23144 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
23145 Location of sqlite database which contains the build results and previously
23146 added specifications.
23148 @item @code{ttl} (default: @code{(* 30 24 3600)})
23149 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
23150 are registered for build results. This means that build results are protected
23151 from garbage collection for at least @var{ttl} seconds.
23153 @item @code{port} (default: @code{8081})
23154 Port number used by the HTTP server.
23156 @item @code{host} (default: @code{"localhost"})
23157 Listen on the network interface for @var{host}. The default is to
23158 accept connections from localhost.
23160 @item @code{specifications} (default: @code{#~'()})
23161 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
23162 where a specification is an association list
23163 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
23164 keys are keywords (@code{#:keyword-example}) as shown in the example
23167 @item @code{use-substitutes?} (default: @code{#f})
23168 This allows using substitutes to avoid building every dependencies of a job
23171 @item @code{one-shot?} (default: @code{#f})
23172 Only evaluate specifications and build derivations once.
23174 @item @code{fallback?} (default: @code{#f})
23175 When substituting a pre-built binary fails, fall back to building
23178 @item @code{extra-options} (default: @code{'()})
23179 Extra options to pass when running the Cuirass processes.
23181 @item @code{cuirass} (default: @code{cuirass})
23182 The Cuirass package to use.
23186 @node Power Management Services
23187 @subsection Power Management Services
23190 @cindex power management with TLP
23191 @subsubheading TLP daemon
23193 The @code{(gnu services pm)} module provides a Guix service definition
23194 for the Linux power management tool TLP.
23196 TLP enables various powersaving modes in userspace and kernel.
23197 Contrary to @code{upower-service}, it is not a passive,
23198 monitoring tool, as it will apply custom settings each time a new power
23199 source is detected. More information can be found at
23200 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
23202 @deffn {Scheme Variable} tlp-service-type
23203 The service type for the TLP tool. Its value should be a valid
23204 TLP configuration (see below). To use the default settings, simply
23207 (service tlp-service-type)
23211 By default TLP does not need much configuration but most TLP parameters
23212 can be tweaked using @code{tlp-configuration}.
23214 Each parameter definition is preceded by its type; for example,
23215 @samp{boolean foo} indicates that the @code{foo} parameter
23216 should be specified as a boolean. Types starting with
23217 @code{maybe-} denote parameters that won't show up in TLP config file
23218 when their value is @code{'disabled}.
23220 @c The following documentation was initially generated by
23221 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
23222 @c documentation is better, so we shouldn't hesitate to edit below as
23223 @c needed. However if the change you want to make to this documentation
23224 @c can be done in an automated way, it's probably easier to change
23225 @c (generate-documentation) than to make it below and have to deal with
23226 @c the churn as TLP updates.
23228 Available @code{tlp-configuration} fields are:
23230 @deftypevr {@code{tlp-configuration} parameter} package tlp
23235 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
23236 Set to true if you wish to enable TLP.
23238 Defaults to @samp{#t}.
23242 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
23243 Default mode when no power supply can be detected. Alternatives are AC
23246 Defaults to @samp{"AC"}.
23250 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
23251 Number of seconds Linux kernel has to wait after the disk goes idle,
23252 before syncing on AC.
23254 Defaults to @samp{0}.
23258 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
23259 Same as @code{disk-idle-ac} but on BAT mode.
23261 Defaults to @samp{2}.
23265 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
23266 Dirty pages flushing periodicity, expressed in seconds.
23268 Defaults to @samp{15}.
23272 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
23273 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
23275 Defaults to @samp{60}.
23279 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
23280 CPU frequency scaling governor on AC mode. With intel_pstate driver,
23281 alternatives are powersave and performance. With acpi-cpufreq driver,
23282 alternatives are ondemand, powersave, performance and conservative.
23284 Defaults to @samp{disabled}.
23288 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
23289 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
23291 Defaults to @samp{disabled}.
23295 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
23296 Set the min available frequency for the scaling governor on AC.
23298 Defaults to @samp{disabled}.
23302 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
23303 Set the max available frequency for the scaling governor on AC.
23305 Defaults to @samp{disabled}.
23309 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
23310 Set the min available frequency for the scaling governor on BAT.
23312 Defaults to @samp{disabled}.
23316 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
23317 Set the max available frequency for the scaling governor on BAT.
23319 Defaults to @samp{disabled}.
23323 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
23324 Limit the min P-state to control the power dissipation of the CPU, in AC
23325 mode. Values are stated as a percentage of the available performance.
23327 Defaults to @samp{disabled}.
23331 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
23332 Limit the max P-state to control the power dissipation of the CPU, in AC
23333 mode. Values are stated as a percentage of the available performance.
23335 Defaults to @samp{disabled}.
23339 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
23340 Same as @code{cpu-min-perf-on-ac} on BAT mode.
23342 Defaults to @samp{disabled}.
23346 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
23347 Same as @code{cpu-max-perf-on-ac} on BAT mode.
23349 Defaults to @samp{disabled}.
23353 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
23354 Enable CPU turbo boost feature on AC mode.
23356 Defaults to @samp{disabled}.
23360 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
23361 Same as @code{cpu-boost-on-ac?} on BAT mode.
23363 Defaults to @samp{disabled}.
23367 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
23368 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
23369 used under light load conditions.
23371 Defaults to @samp{#f}.
23375 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
23376 Same as @code{sched-powersave-on-ac?} but on BAT mode.
23378 Defaults to @samp{#t}.
23382 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
23383 Enable Linux kernel NMI watchdog.
23385 Defaults to @samp{#f}.
23389 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
23390 For Linux kernels with PHC patch applied, change CPU voltages. An
23391 example value would be @samp{"F:V F:V F:V F:V"}.
23393 Defaults to @samp{disabled}.
23397 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
23398 Set CPU performance versus energy saving policy on AC. Alternatives are
23399 performance, normal, powersave.
23401 Defaults to @samp{"performance"}.
23405 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
23406 Same as @code{energy-perf-policy-ac} but on BAT mode.
23408 Defaults to @samp{"powersave"}.
23412 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
23417 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
23418 Hard disk advanced power management level.
23422 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
23423 Same as @code{disk-apm-bat} but on BAT mode.
23427 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
23428 Hard disk spin down timeout. One value has to be specified for each
23429 declared hard disk.
23431 Defaults to @samp{disabled}.
23435 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
23436 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
23438 Defaults to @samp{disabled}.
23442 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
23443 Select IO scheduler for disk devices. One value has to be specified for
23444 each declared hard disk. Example alternatives are cfq, deadline and
23447 Defaults to @samp{disabled}.
23451 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
23452 SATA aggressive link power management (ALPM) level. Alternatives are
23453 min_power, medium_power, max_performance.
23455 Defaults to @samp{"max_performance"}.
23459 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
23460 Same as @code{sata-linkpwr-ac} but on BAT mode.
23462 Defaults to @samp{"min_power"}.
23466 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
23467 Exclude specified SATA host devices for link power management.
23469 Defaults to @samp{disabled}.
23473 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
23474 Enable Runtime Power Management for AHCI controller and disks on AC
23477 Defaults to @samp{disabled}.
23481 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
23482 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
23484 Defaults to @samp{disabled}.
23488 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
23489 Seconds of inactivity before disk is suspended.
23491 Defaults to @samp{15}.
23495 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
23496 PCI Express Active State Power Management level. Alternatives are
23497 default, performance, powersave.
23499 Defaults to @samp{"performance"}.
23503 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
23504 Same as @code{pcie-aspm-ac} but on BAT mode.
23506 Defaults to @samp{"powersave"}.
23510 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
23511 Radeon graphics clock speed level. Alternatives are low, mid, high,
23514 Defaults to @samp{"high"}.
23518 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
23519 Same as @code{radeon-power-ac} but on BAT mode.
23521 Defaults to @samp{"low"}.
23525 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
23526 Radeon dynamic power management method (DPM). Alternatives are battery,
23529 Defaults to @samp{"performance"}.
23533 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
23534 Same as @code{radeon-dpm-state-ac} but on BAT mode.
23536 Defaults to @samp{"battery"}.
23540 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
23541 Radeon DPM performance level. Alternatives are auto, low, high.
23543 Defaults to @samp{"auto"}.
23547 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
23548 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
23550 Defaults to @samp{"auto"}.
23554 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
23555 Wifi power saving mode.
23557 Defaults to @samp{#f}.
23561 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
23562 Same as @code{wifi-power-ac?} but on BAT mode.
23564 Defaults to @samp{#t}.
23568 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
23569 Disable wake on LAN.
23571 Defaults to @samp{#t}.
23575 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
23576 Timeout duration in seconds before activating audio power saving on
23577 Intel HDA and AC97 devices. A value of 0 disables power saving.
23579 Defaults to @samp{0}.
23583 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
23584 Same as @code{sound-powersave-ac} but on BAT mode.
23586 Defaults to @samp{1}.
23590 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
23591 Disable controller in powersaving mode on Intel HDA devices.
23593 Defaults to @samp{#t}.
23597 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
23598 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
23599 powered on again by releasing (and reinserting) the eject lever or by
23600 pressing the disc eject button on newer models.
23602 Defaults to @samp{#f}.
23606 @deftypevr {@code{tlp-configuration} parameter} string bay-device
23607 Name of the optical drive device to power off.
23609 Defaults to @samp{"sr0"}.
23613 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
23614 Runtime Power Management for PCI(e) bus devices. Alternatives are on
23617 Defaults to @samp{"on"}.
23621 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
23622 Same as @code{runtime-pm-ac} but on BAT mode.
23624 Defaults to @samp{"auto"}.
23628 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
23629 Runtime Power Management for all PCI(e) bus devices, except blacklisted
23632 Defaults to @samp{#t}.
23636 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
23637 Exclude specified PCI(e) device addresses from Runtime Power Management.
23639 Defaults to @samp{disabled}.
23643 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
23644 Exclude PCI(e) devices assigned to the specified drivers from Runtime
23649 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
23650 Enable USB autosuspend feature.
23652 Defaults to @samp{#t}.
23656 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
23657 Exclude specified devices from USB autosuspend.
23659 Defaults to @samp{disabled}.
23663 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
23664 Exclude WWAN devices from USB autosuspend.
23666 Defaults to @samp{#t}.
23670 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
23671 Include specified devices into USB autosuspend, even if they are already
23672 excluded by the driver or via @code{usb-blacklist-wwan?}.
23674 Defaults to @samp{disabled}.
23678 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
23679 Enable USB autosuspend before shutdown.
23681 Defaults to @samp{disabled}.
23685 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
23686 Restore radio device state (bluetooth, wifi, wwan) from previous
23687 shutdown on system startup.
23689 Defaults to @samp{#f}.
23694 @cindex CPU frequency scaling with thermald
23695 @subsubheading Thermald daemon
23697 The @code{(gnu services pm)} module provides an interface to
23698 thermald, a CPU frequency scaling service which helps prevent overheating.
23700 @defvr {Scheme Variable} thermald-service-type
23701 This is the service type for
23702 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
23703 Thermal Daemon, which is responsible for controlling the thermal state
23704 of processors and preventing overheating.
23707 @deftp {Data Type} thermald-configuration
23708 Data type representing the configuration of @code{thermald-service-type}.
23711 @item @code{ignore-cpuid-check?} (default: @code{#f})
23712 Ignore cpuid check for supported CPU models.
23714 @item @code{thermald} (default: @var{thermald})
23715 Package object of thermald.
23720 @node Audio Services
23721 @subsection Audio Services
23723 The @code{(gnu services audio)} module provides a service to start MPD
23724 (the Music Player Daemon).
23727 @subsubheading Music Player Daemon
23729 The Music Player Daemon (MPD) is a service that can play music while
23730 being controlled from the local machine or over the network by a variety
23733 The following example shows how one might run @code{mpd} as user
23734 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
23737 (service mpd-service-type
23743 @defvr {Scheme Variable} mpd-service-type
23744 The service type for @command{mpd}
23747 @deftp {Data Type} mpd-configuration
23748 Data type representing the configuration of @command{mpd}.
23751 @item @code{user} (default: @code{"mpd"})
23752 The user to run mpd as.
23754 @item @code{music-dir} (default: @code{"~/Music"})
23755 The directory to scan for music files.
23757 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
23758 The directory to store playlists.
23760 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
23761 The location of the music database.
23763 @item @code{state-file} (default: @code{"~/.mpd/state"})
23764 The location of the file that stores current MPD's state.
23766 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
23767 The location of the sticker database.
23769 @item @code{port} (default: @code{"6600"})
23770 The port to run mpd on.
23772 @item @code{address} (default: @code{"any"})
23773 The address that mpd will bind to. To use a Unix domain socket,
23774 an absolute path can be specified here.
23776 @item @code{outputs} (default: @code{"(list (mpd-output))"})
23777 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
23782 @deftp {Data Type} mpd-output
23783 Data type representing an @command{mpd} audio output.
23786 @item @code{name} (default: @code{"MPD"})
23787 The name of the audio output.
23789 @item @code{type} (default: @code{"pulse"})
23790 The type of audio output.
23792 @item @code{enabled?} (default: @code{#t})
23793 Specifies whether this audio output is enabled when MPD is started. By
23794 default, all audio outputs are enabled. This is just the default
23795 setting when there is no state file; with a state file, the previous
23798 @item @code{tags?} (default: @code{#t})
23799 If set to @code{#f}, then MPD will not send tags to this output. This
23800 is only useful for output plugins that can receive tags, for example the
23801 @code{httpd} output plugin.
23803 @item @code{always-on?} (default: @code{#f})
23804 If set to @code{#t}, then MPD attempts to keep this audio output always
23805 open. This may be useful for streaming servers, when you don’t want to
23806 disconnect all listeners even when playback is accidentally stopped.
23808 @item @code{mixer-type}
23809 This field accepts a symbol that specifies which mixer should be used
23810 for this audio output: the @code{hardware} mixer, the @code{software}
23811 mixer, the @code{null} mixer (allows setting the volume, but with no
23812 effect; this can be used as a trick to implement an external mixer
23813 External Mixer) or no mixer (@code{none}).
23815 @item @code{extra-options} (default: @code{'()"})
23816 An association list of option symbols to string values to be appended to
23817 the audio output configuration.
23822 The following example shows a configuration of @code{mpd} that provides
23823 an HTTP audio streaming output.
23826 (service mpd-service-type
23834 `((encoder . "vorbis")
23835 (port . "8080"))))))))
23839 @node Virtualization Services
23840 @subsection Virtualization services
23842 The @code{(gnu services virtualization)} module provides services for
23843 the libvirt and virtlog daemons, as well as other virtualization-related
23846 @subsubheading Libvirt daemon
23847 @code{libvirtd} is the server side daemon component of the libvirt
23848 virtualization management system. This daemon runs on host servers
23849 and performs required management tasks for virtualized guests.
23851 @deffn {Scheme Variable} libvirt-service-type
23852 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
23853 Its value must be a @code{libvirt-configuration}.
23856 (service libvirt-service-type
23857 (libvirt-configuration
23858 (unix-sock-group "libvirt")
23859 (tls-port "16555")))
23863 @c Auto-generated with (generate-libvirt-documentation)
23864 Available @code{libvirt-configuration} fields are:
23866 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
23871 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
23872 Flag listening for secure TLS connections on the public TCP/IP port.
23873 must set @code{listen} for this to have any effect.
23875 It is necessary to setup a CA and issue server certificates before using
23878 Defaults to @samp{#t}.
23882 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
23883 Listen for unencrypted TCP connections on the public TCP/IP port. must
23884 set @code{listen} for this to have any effect.
23886 Using the TCP socket requires SASL authentication by default. Only SASL
23887 mechanisms which support data encryption are allowed. This is
23888 DIGEST_MD5 and GSSAPI (Kerberos5)
23890 Defaults to @samp{#f}.
23894 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
23895 Port for accepting secure TLS connections This can be a port number, or
23898 Defaults to @samp{"16514"}.
23902 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
23903 Port for accepting insecure TCP connections This can be a port number,
23906 Defaults to @samp{"16509"}.
23910 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
23911 IP address or hostname used for client connections.
23913 Defaults to @samp{"0.0.0.0"}.
23917 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
23918 Flag toggling mDNS advertisement of the libvirt service.
23920 Alternatively can disable for all services on a host by stopping the
23923 Defaults to @samp{#f}.
23927 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
23928 Default mDNS advertisement name. This must be unique on the immediate
23931 Defaults to @samp{"Virtualization Host <hostname>"}.
23935 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
23936 UNIX domain socket group ownership. This can be used to allow a
23937 'trusted' set of users access to management capabilities without
23940 Defaults to @samp{"root"}.
23944 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
23945 UNIX socket permissions for the R/O socket. This is used for monitoring
23948 Defaults to @samp{"0777"}.
23952 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
23953 UNIX socket permissions for the R/W socket. Default allows only root.
23954 If PolicyKit is enabled on the socket, the default will change to allow
23955 everyone (eg, 0777)
23957 Defaults to @samp{"0770"}.
23961 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
23962 UNIX socket permissions for the admin socket. Default allows only owner
23963 (root), do not change it unless you are sure to whom you are exposing
23966 Defaults to @samp{"0777"}.
23970 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
23971 The directory in which sockets will be found/created.
23973 Defaults to @samp{"/var/run/libvirt"}.
23977 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
23978 Authentication scheme for UNIX read-only sockets. By default socket
23979 permissions allow anyone to connect
23981 Defaults to @samp{"polkit"}.
23985 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
23986 Authentication scheme for UNIX read-write sockets. By default socket
23987 permissions only allow root. If PolicyKit support was compiled into
23988 libvirt, the default will be to use 'polkit' auth.
23990 Defaults to @samp{"polkit"}.
23994 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
23995 Authentication scheme for TCP sockets. If you don't enable SASL, then
23996 all TCP traffic is cleartext. Don't do this outside of a dev/test
23999 Defaults to @samp{"sasl"}.
24003 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
24004 Authentication scheme for TLS sockets. TLS sockets already have
24005 encryption provided by the TLS layer, and limited authentication is done
24008 It is possible to make use of any SASL authentication mechanism as well,
24009 by using 'sasl' for this option
24011 Defaults to @samp{"none"}.
24015 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
24016 API access control scheme.
24018 By default an authenticated user is allowed access to all APIs. Access
24019 drivers can place restrictions on this.
24021 Defaults to @samp{()}.
24025 @deftypevr {@code{libvirt-configuration} parameter} string key-file
24026 Server key file path. If set to an empty string, then no private key is
24029 Defaults to @samp{""}.
24033 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
24034 Server key file path. If set to an empty string, then no certificate is
24037 Defaults to @samp{""}.
24041 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
24042 Server key file path. If set to an empty string, then no CA certificate
24045 Defaults to @samp{""}.
24049 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
24050 Certificate revocation list path. If set to an empty string, then no
24053 Defaults to @samp{""}.
24057 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
24058 Disable verification of our own server certificates.
24060 When libvirtd starts it performs some sanity checks against its own
24063 Defaults to @samp{#f}.
24067 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
24068 Disable verification of client certificates.
24070 Client certificate verification is the primary authentication mechanism.
24071 Any client which does not present a certificate signed by the CA will be
24074 Defaults to @samp{#f}.
24078 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
24079 Whitelist of allowed x509 Distinguished Name.
24081 Defaults to @samp{()}.
24085 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
24086 Whitelist of allowed SASL usernames. The format for username depends on
24087 the SASL authentication mechanism.
24089 Defaults to @samp{()}.
24093 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
24094 Override the compile time default TLS priority string. The default is
24095 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
24096 is desired for libvirt to deviate from the global default settings.
24098 Defaults to @samp{"NORMAL"}.
24102 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
24103 Maximum number of concurrent client connections to allow over all
24106 Defaults to @samp{5000}.
24110 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
24111 Maximum length of queue of connections waiting to be accepted by the
24112 daemon. Note, that some protocols supporting retransmission may obey
24113 this so that a later reattempt at connection succeeds.
24115 Defaults to @samp{1000}.
24119 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
24120 Maximum length of queue of accepted but not yet authenticated clients.
24121 Set this to zero to turn this feature off
24123 Defaults to @samp{20}.
24127 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
24128 Number of workers to start up initially.
24130 Defaults to @samp{5}.
24134 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
24135 Maximum number of worker threads.
24137 If the number of active clients exceeds @code{min-workers}, then more
24138 threads are spawned, up to max_workers limit. Typically you'd want
24139 max_workers to equal maximum number of clients allowed.
24141 Defaults to @samp{20}.
24145 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
24146 Number of priority workers. If all workers from above pool are stuck,
24147 some calls marked as high priority (notably domainDestroy) can be
24148 executed in this pool.
24150 Defaults to @samp{5}.
24154 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
24155 Total global limit on concurrent RPC calls.
24157 Defaults to @samp{20}.
24161 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
24162 Limit on concurrent requests from a single client connection. To avoid
24163 one client monopolizing the server this should be a small fraction of
24164 the global max_requests and max_workers parameter.
24166 Defaults to @samp{5}.
24170 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
24171 Same as @code{min-workers} but for the admin interface.
24173 Defaults to @samp{1}.
24177 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
24178 Same as @code{max-workers} but for the admin interface.
24180 Defaults to @samp{5}.
24184 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
24185 Same as @code{max-clients} but for the admin interface.
24187 Defaults to @samp{5}.
24191 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
24192 Same as @code{max-queued-clients} but for the admin interface.
24194 Defaults to @samp{5}.
24198 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
24199 Same as @code{max-client-requests} but for the admin interface.
24201 Defaults to @samp{5}.
24205 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
24206 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
24208 Defaults to @samp{3}.
24212 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
24215 A filter allows to select a different logging level for a given category
24216 of logs The format for a filter is one of:
24227 where @code{name} is a string which is matched against the category
24228 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
24229 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
24230 name in the filter can be a substring of the full category name, in
24231 order to match multiple similar categories), the optional @samp{"+"}
24232 prefix tells libvirt to log stack trace for each message matching name,
24233 and @code{x} is the minimal level where matching messages should be
24251 Multiple filters can be defined in a single filters statement, they just
24252 need to be separated by spaces.
24254 Defaults to @samp{"3:remote 4:event"}.
24258 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
24261 An output is one of the places to save logging information. The format
24262 for an output can be:
24266 output goes to stderr
24268 @item x:syslog:name
24269 use syslog for the output and use the given name as the ident
24271 @item x:file:file_path
24272 output to a file, with the given filepath
24275 output to journald logging system
24279 In all case the x prefix is the minimal level, acting as a filter
24296 Multiple outputs can be defined, they just need to be separated by
24299 Defaults to @samp{"3:stderr"}.
24303 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
24304 Allows usage of the auditing subsystem to be altered
24308 0: disable all auditing
24311 1: enable auditing, only if enabled on host
24314 2: enable auditing, and exit if disabled on host.
24318 Defaults to @samp{1}.
24322 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
24323 Send audit messages via libvirt logging infrastructure.
24325 Defaults to @samp{#f}.
24329 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
24330 Host UUID. UUID must not have all digits be the same.
24332 Defaults to @samp{""}.
24336 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
24337 Source to read host UUID.
24341 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
24344 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
24348 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
24351 Defaults to @samp{"smbios"}.
24355 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
24356 A keepalive message is sent to a client after @code{keepalive_interval}
24357 seconds of inactivity to check if the client is still responding. If
24358 set to -1, libvirtd will never send keepalive requests; however clients
24359 can still send them and the daemon will send responses.
24361 Defaults to @samp{5}.
24365 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
24366 Maximum number of keepalive messages that are allowed to be sent to the
24367 client without getting any response before the connection is considered
24370 In other words, the connection is automatically closed approximately
24371 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
24372 the last message received from the client. When @code{keepalive-count}
24373 is set to 0, connections will be automatically closed after
24374 @code{keepalive-interval} seconds of inactivity without sending any
24375 keepalive messages.
24377 Defaults to @samp{5}.
24381 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
24382 Same as above but for admin interface.
24384 Defaults to @samp{5}.
24388 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
24389 Same as above but for admin interface.
24391 Defaults to @samp{5}.
24395 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
24396 Timeout for Open vSwitch calls.
24398 The @code{ovs-vsctl} utility is used for the configuration and its
24399 timeout option is set by default to 5 seconds to avoid potential
24400 infinite waits blocking libvirt.
24402 Defaults to @samp{5}.
24406 @c %end of autogenerated docs
24408 @subsubheading Virtlog daemon
24409 The virtlogd service is a server side daemon component of libvirt that is
24410 used to manage logs from virtual machine consoles.
24412 This daemon is not used directly by libvirt client applications, rather it
24413 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
24414 standalone daemon, the main @code{libvirtd} daemon can be restarted without
24415 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
24416 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
24418 @deffn {Scheme Variable} virtlog-service-type
24419 This is the type of the virtlog daemon.
24420 Its value must be a @code{virtlog-configuration}.
24423 (service virtlog-service-type
24424 (virtlog-configuration
24425 (max-clients 1000)))
24429 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
24430 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
24432 Defaults to @samp{3}.
24436 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
24439 A filter allows to select a different logging level for a given category
24440 of logs The format for a filter is one of:
24451 where @code{name} is a string which is matched against the category
24452 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
24453 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
24454 be a substring of the full category name, in order to match multiple
24455 similar categories), the optional "+" prefix tells libvirt to log stack
24456 trace for each message matching name, and @code{x} is the minimal level
24457 where matching messages should be logged:
24474 Multiple filters can be defined in a single filters statement, they just
24475 need to be separated by spaces.
24477 Defaults to @samp{"3:remote 4:event"}.
24481 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
24484 An output is one of the places to save logging information The format
24485 for an output can be:
24489 output goes to stderr
24491 @item x:syslog:name
24492 use syslog for the output and use the given name as the ident
24494 @item x:file:file_path
24495 output to a file, with the given filepath
24498 output to journald logging system
24502 In all case the x prefix is the minimal level, acting as a filter
24519 Multiple outputs can be defined, they just need to be separated by
24522 Defaults to @samp{"3:stderr"}.
24526 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
24527 Maximum number of concurrent client connections to allow over all
24530 Defaults to @samp{1024}.
24534 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
24535 Maximum file size before rolling over.
24537 Defaults to @samp{2MB}
24541 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
24542 Maximum number of backup files to keep.
24544 Defaults to @samp{3}
24548 @subsubheading Transparent Emulation with QEMU
24551 @cindex @code{binfmt_misc}
24552 @code{qemu-binfmt-service-type} provides support for transparent
24553 emulation of program binaries built for different architectures---e.g.,
24554 it allows you to transparently execute an ARMv7 program on an x86_64
24555 machine. It achieves this by combining the @uref{https://www.qemu.org,
24556 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
24558 @defvr {Scheme Variable} qemu-binfmt-service-type
24559 This is the type of the QEMU/binfmt service for transparent emulation.
24560 Its value must be a @code{qemu-binfmt-configuration} object, which
24561 specifies the QEMU package to use as well as the architecture we want to
24565 (service qemu-binfmt-service-type
24566 (qemu-binfmt-configuration
24567 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
24570 In this example, we enable transparent emulation for the ARM and aarch64
24571 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
24572 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
24573 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
24576 @deftp {Data Type} qemu-binfmt-configuration
24577 This is the configuration for the @code{qemu-binfmt} service.
24580 @item @code{platforms} (default: @code{'()})
24581 The list of emulated QEMU platforms. Each item must be a @dfn{platform
24582 object} as returned by @code{lookup-qemu-platforms} (see below).
24584 @item @code{guix-support?} (default: @code{#f})
24585 When it is true, QEMU and all its dependencies are added to the build
24586 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
24587 @option{--chroot-directory} option}). This allows the @code{binfmt_misc}
24588 handlers to be used within the build environment, which in turn means
24589 that you can transparently build programs for another architecture.
24591 For example, let's suppose you're on an x86_64 machine and you have this
24595 (service qemu-binfmt-service-type
24596 (qemu-binfmt-configuration
24597 (platforms (lookup-qemu-platforms "arm"))
24598 (guix-support? #t)))
24604 guix build -s armhf-linux inkscape
24608 and it will build Inkscape for ARMv7 @emph{as if it were a native
24609 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
24610 if you'd like to test a package build for an architecture you don't have
24613 @item @code{qemu} (default: @code{qemu})
24614 The QEMU package to use.
24618 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
24619 Return the list of QEMU platform objects corresponding to
24620 @var{platforms}@dots{}. @var{platforms} must be a list of strings
24621 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
24622 @code{"mips64el"}, and so on.
24625 @deffn {Scheme Procedure} qemu-platform? @var{obj}
24626 Return true if @var{obj} is a platform object.
24629 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
24630 Return the name of @var{platform}---a string such as @code{"arm"}.
24634 @subsubheading The Hurd in a Virtual Machine
24636 @cindex @code{hurd}
24639 Service @code{hurd-vm} provides support for running GNU/Hurd in a
24640 virtual machine (VM), a so-called ``Childhurd''. The virtual machine is
24641 a Shepherd service that can be referred to by the names @code{hurd-vm}
24642 and @code{childhurd} and be controlled with commands such as:
24646 herd stop childhurd
24649 The given GNU/Hurd operating system configuration is cross-compiled.
24651 @defvr {Scheme Variable} hurd-vm-service-type
24652 This is the type of the Hurd in a Virtual Machine service. Its value
24653 must be a @code{hurd-vm-configuration} object, which specifies the
24654 operating system (@pxref{operating-system Reference}) and the disk size
24655 for the Hurd Virtual Machine, the QEMU package to use as well as the
24656 options for running it.
24661 (service hurd-vm-service-type
24662 (hurd-vm-configuration
24663 (disk-size (* 5000 (expt 2 20))) ;5G
24664 (memory-size 1024))) ;1024MiB
24667 would create a disk image big enough to build GNU@tie{}Hello, with some
24671 @deftp {Data Type} hurd-vm-configuration
24672 The data type representing the configuration for
24673 @code{hurd-vm-service-type}.
24676 @item @code{os} (default: @var{%hurd-vm-operating-system})
24677 The operating system to instantiate. This default is bare-bones with a
24678 permissive OpenSSH secure shell daemon listening on port 2222
24679 (@pxref{Networking Services, @code{openssh-service-type}}).
24681 @item @code{qemu} (default: @code{qemu-minimal})
24682 The QEMU package to use.
24684 @item @code{image} (default: @var{hurd-vm-disk-image})
24685 The procedure used to build the disk-image built from this
24688 @item @code{disk-size} (default: @code{'guess})
24689 The size of the disk image.
24691 @item @code{memory-size} (default: @code{512})
24692 The memory size of the Virtual Machine in mebibytes.
24694 @item @code{options} (default: @code{'("--device"} @code{"rtl8139,netdev=net0"} @
24695 @code{"--netdev"} @
24696 @code{"user,id=net0,hostfwd=tcp:127.0.0.1:20022-:2222,hostfwd=tcp:127.0.0.1:25900-:5900"} @
24697 @code{"--snapshot"} @
24699 The extra options for running QEMU.
24703 Note that by default the VM image is volatile, i.e., once stopped the
24704 contents are lost. If you want a stateful image instead, override the
24705 configuration's @code{image} and @code{options} without
24706 the @code{--snapshot} flag using something along these lines:
24709 (service hurd-vm-service-type
24710 (hurd-vm-configuration
24711 (image (const "/out/of/store/writable/hurd.img"))
24712 (options '("--device" "rtl8139,netdev=net0"
24714 "user,id=net0,hostfwd=tcp:127.0.0.1:20022-:2222"))))
24717 @node Version Control Services
24718 @subsection Version Control Services
24720 The @code{(gnu services version-control)} module provides a service to
24721 allow remote access to local Git repositories. There are three options:
24722 the @code{git-daemon-service}, which provides access to repositories via
24723 the @code{git://} unsecured TCP-based protocol, extending the
24724 @code{nginx} web server to proxy some requests to
24725 @code{git-http-backend}, or providing a web interface with
24726 @code{cgit-service-type}.
24728 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
24730 Return a service that runs @command{git daemon}, a simple TCP server to
24731 expose repositories over the Git protocol for anonymous access.
24733 The optional @var{config} argument should be a
24734 @code{<git-daemon-configuration>} object, by default it allows read-only
24735 access to exported@footnote{By creating the magic file
24736 @file{git-daemon-export-ok} in the repository directory.} repositories under
24741 @deftp {Data Type} git-daemon-configuration
24742 Data type representing the configuration for @code{git-daemon-service}.
24745 @item @code{package} (default: @var{git})
24746 Package object of the Git distributed version control system.
24748 @item @code{export-all?} (default: @var{#f})
24749 Whether to allow access for all Git repositories, even if they do not
24750 have the @file{git-daemon-export-ok} file.
24752 @item @code{base-path} (default: @file{/srv/git})
24753 Whether to remap all the path requests as relative to the given path.
24754 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
24755 then if you later try to pull @code{git://example.com/hello.git}, git
24756 daemon will interpret the path as @code{/srv/git/hello.git}.
24758 @item @code{user-path} (default: @var{#f})
24759 Whether to allow @code{~user} notation to be used in requests. When
24760 specified with empty string, requests to @code{git://host/~alice/foo} is
24761 taken as a request to access @code{foo} repository in the home directory
24762 of user @code{alice}. If @var{(user-path "path")} is specified, the
24763 same request is taken as a request to access @code{path/foo} repository
24764 in the home directory of user @code{alice}.
24766 @item @code{listen} (default: @var{'()})
24767 Whether to listen on specific IP addresses or hostnames, defaults to
24770 @item @code{port} (default: @var{#f})
24771 Whether to listen on an alternative port, which defaults to 9418.
24773 @item @code{whitelist} (default: @var{'()})
24774 If not empty, only allow access to this list of directories.
24776 @item @code{extra-options} (default: @var{'()})
24777 Extra options will be passed to @code{git daemon}, please run
24778 @command{man git-daemon} for more information.
24783 The @code{git://} protocol lacks authentication. When you pull from a
24784 repository fetched via @code{git://}, you don't know whether the data you
24785 receive was modified or is even coming from the specified host, and your
24786 connection is subject to eavesdropping. It's better to use an authenticated
24787 and encrypted transport, such as @code{https}. Although Git allows you
24788 to serve repositories using unsophisticated file-based web servers,
24789 there is a faster protocol implemented by the @code{git-http-backend}
24790 program. This program is the back-end of a proper Git web service. It
24791 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
24792 on running the necessary @code{fcgiwrap} daemon.
24794 Guix has a separate configuration data type for serving Git repositories
24797 @deftp {Data Type} git-http-configuration
24798 Data type representing the configuration for a future
24799 @code{git-http-service-type}; can currently be used to configure Nginx
24800 trough @code{git-http-nginx-location-configuration}.
24803 @item @code{package} (default: @var{git})
24804 Package object of the Git distributed version control system.
24806 @item @code{git-root} (default: @file{/srv/git})
24807 Directory containing the Git repositories to expose to the world.
24809 @item @code{export-all?} (default: @var{#f})
24810 Whether to expose access for all Git repositories in @var{git-root},
24811 even if they do not have the @file{git-daemon-export-ok} file.
24813 @item @code{uri-path} (default: @file{/git/})
24814 Path prefix for Git access. With the default @code{/git/} prefix, this
24815 will map @code{http://@var{server}/git/@var{repo}.git} to
24816 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
24817 with this prefix are not passed on to this Git instance.
24819 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
24820 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
24825 There is no @code{git-http-service-type}, currently; instead you can
24826 create an @code{nginx-location-configuration} from a
24827 @code{git-http-configuration} and then add that location to a web
24830 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
24831 [config=(git-http-configuration)]
24832 Compute an @code{nginx-location-configuration} that corresponds to the
24833 given Git http configuration. An example nginx service definition to
24834 serve the default @file{/srv/git} over HTTPS might be:
24837 (service nginx-service-type
24838 (nginx-configuration
24841 (nginx-server-configuration
24842 (listen '("443 ssl"))
24843 (server-name "git.my-host.org")
24845 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
24846 (ssl-certificate-key
24847 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
24850 (git-http-nginx-location-configuration
24851 (git-http-configuration (uri-path "/"))))))))))
24854 This example assumes that you are using Let's Encrypt to get your TLS
24855 certificate. @xref{Certificate Services}. The default @code{certbot}
24856 service will redirect all HTTP traffic on @code{git.my-host.org} to
24857 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
24858 system services. @xref{Web Services}.
24861 @subsubheading Cgit Service
24863 @cindex Cgit service
24864 @cindex Git, web interface
24865 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
24866 repositories written in C.
24868 The following example will configure the service with default values.
24869 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
24872 (service cgit-service-type)
24875 The @code{file-object} type designates either a file-like object
24876 (@pxref{G-Expressions, file-like objects}) or a string.
24878 @c %start of fragment
24880 Available @code{cgit-configuration} fields are:
24882 @deftypevr {@code{cgit-configuration} parameter} package package
24887 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
24888 NGINX configuration.
24892 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
24893 Specifies a command which will be invoked to format the content of about
24894 pages (both top-level and for each repository).
24896 Defaults to @samp{""}.
24900 @deftypevr {@code{cgit-configuration} parameter} string agefile
24901 Specifies a path, relative to each repository path, which can be used to
24902 specify the date and time of the youngest commit in the repository.
24904 Defaults to @samp{""}.
24908 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
24909 Specifies a command that will be invoked for authenticating repository
24912 Defaults to @samp{""}.
24916 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
24917 Flag which, when set to @samp{age}, enables date ordering in the branch
24918 ref list, and when set @samp{name} enables ordering by branch name.
24920 Defaults to @samp{"name"}.
24924 @deftypevr {@code{cgit-configuration} parameter} string cache-root
24925 Path used to store the cgit cache entries.
24927 Defaults to @samp{"/var/cache/cgit"}.
24931 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
24932 Number which specifies the time-to-live, in minutes, for the cached
24933 version of repository pages accessed with a fixed SHA1.
24935 Defaults to @samp{-1}.
24939 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
24940 Number which specifies the time-to-live, in minutes, for the cached
24941 version of repository pages accessed without a fixed SHA1.
24943 Defaults to @samp{5}.
24947 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
24948 Number which specifies the time-to-live, in minutes, for the cached
24949 version of the repository summary page.
24951 Defaults to @samp{5}.
24955 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
24956 Number which specifies the time-to-live, in minutes, for the cached
24957 version of the repository index page.
24959 Defaults to @samp{5}.
24963 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
24964 Number which specifies the time-to-live, in minutes, for the result of
24965 scanning a path for Git repositories.
24967 Defaults to @samp{15}.
24971 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
24972 Number which specifies the time-to-live, in minutes, for the cached
24973 version of the repository about page.
24975 Defaults to @samp{15}.
24979 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
24980 Number which specifies the time-to-live, in minutes, for the cached
24981 version of snapshots.
24983 Defaults to @samp{5}.
24987 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
24988 The maximum number of entries in the cgit cache. When set to @samp{0},
24989 caching is disabled.
24991 Defaults to @samp{0}.
24995 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
24996 Sort items in the repo list case sensitively.
24998 Defaults to @samp{#t}.
25002 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
25003 List of common prefixes which, when combined with a repository URL,
25004 generates valid clone URLs for the repository.
25006 Defaults to @samp{()}.
25010 @deftypevr {@code{cgit-configuration} parameter} list clone-url
25011 List of @code{clone-url} templates.
25013 Defaults to @samp{()}.
25017 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
25018 Command which will be invoked to format commit messages.
25020 Defaults to @samp{""}.
25024 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
25025 Flag which, when set to @samp{date}, enables strict date ordering in the
25026 commit log, and when set to @samp{topo} enables strict topological
25029 Defaults to @samp{"git log"}.
25033 @deftypevr {@code{cgit-configuration} parameter} file-object css
25034 URL which specifies the css document to include in all cgit pages.
25036 Defaults to @samp{"/share/cgit/cgit.css"}.
25040 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
25041 Specifies a command which will be invoked to format names and email
25042 address of committers, authors, and taggers, as represented in various
25043 places throughout the cgit interface.
25045 Defaults to @samp{""}.
25049 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
25050 Flag which, when set to @samp{#t}, will make cgit generate a HTML
25051 fragment suitable for embedding in other HTML pages.
25053 Defaults to @samp{#f}.
25057 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
25058 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
25059 commit history graph to the left of the commit messages in the
25060 repository log page.
25062 Defaults to @samp{#f}.
25066 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
25067 Flag which, when set to @samp{#t}, allows all filter settings to be
25068 overridden in repository-specific cgitrc files.
25070 Defaults to @samp{#f}.
25074 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
25075 Flag which, when set to @samp{#t}, allows users to follow a file in the
25078 Defaults to @samp{#f}.
25082 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
25083 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
25086 Defaults to @samp{#t}.
25090 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
25091 Flag which, when set to @samp{#t}, will make cgit generate extra links
25092 "summary", "commit", "tree" for each repo in the repository index.
25094 Defaults to @samp{#f}.
25098 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
25099 Flag which, when set to @samp{#t}, will make cgit display the owner of
25100 each repo in the repository index.
25102 Defaults to @samp{#t}.
25106 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
25107 Flag which, when set to @samp{#t}, will make cgit print the number of
25108 modified files for each commit on the repository log page.
25110 Defaults to @samp{#f}.
25114 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
25115 Flag which, when set to @samp{#t}, will make cgit print the number of
25116 added and removed lines for each commit on the repository log page.
25118 Defaults to @samp{#f}.
25122 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
25123 Flag which, when set to @code{#t}, will make cgit display remote
25124 branches in the summary and refs views.
25126 Defaults to @samp{#f}.
25130 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
25131 Flag which, when set to @code{1}, will make cgit use the subject of the
25132 parent commit as link text when generating links to parent commits in
25135 Defaults to @samp{#f}.
25139 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
25140 Flag which, when set to @samp{#t}, will make cgit use the subject of the
25141 parent commit as link text when generating links to parent commits in
25144 Defaults to @samp{#f}.
25148 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
25149 Flag which, when set to @samp{#t}, will make cgit generate linenumber
25150 links for plaintext blobs printed in the tree view.
25152 Defaults to @samp{#t}.
25156 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
25157 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
25158 set any repo specific settings.
25160 Defaults to @samp{#f}.
25164 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
25165 URL used as link to a shortcut icon for cgit.
25167 Defaults to @samp{"/favicon.ico"}.
25171 @deftypevr {@code{cgit-configuration} parameter} string footer
25172 The content of the file specified with this option will be included
25173 verbatim at the bottom of all pages (i.e.@: it replaces the standard
25174 "generated by..."@: message).
25176 Defaults to @samp{""}.
25180 @deftypevr {@code{cgit-configuration} parameter} string head-include
25181 The content of the file specified with this option will be included
25182 verbatim in the HTML HEAD section on all pages.
25184 Defaults to @samp{""}.
25188 @deftypevr {@code{cgit-configuration} parameter} string header
25189 The content of the file specified with this option will be included
25190 verbatim at the top of all pages.
25192 Defaults to @samp{""}.
25196 @deftypevr {@code{cgit-configuration} parameter} file-object include
25197 Name of a configfile to include before the rest of the current config-
25200 Defaults to @samp{""}.
25204 @deftypevr {@code{cgit-configuration} parameter} string index-header
25205 The content of the file specified with this option will be included
25206 verbatim above the repository index.
25208 Defaults to @samp{""}.
25212 @deftypevr {@code{cgit-configuration} parameter} string index-info
25213 The content of the file specified with this option will be included
25214 verbatim below the heading on the repository index page.
25216 Defaults to @samp{""}.
25220 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
25221 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
25222 in the servers timezone.
25224 Defaults to @samp{#f}.
25228 @deftypevr {@code{cgit-configuration} parameter} file-object logo
25229 URL which specifies the source of an image which will be used as a logo
25232 Defaults to @samp{"/share/cgit/cgit.png"}.
25236 @deftypevr {@code{cgit-configuration} parameter} string logo-link
25237 URL loaded when clicking on the cgit logo image.
25239 Defaults to @samp{""}.
25243 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
25244 Command which will be invoked to format the Owner column of the main
25247 Defaults to @samp{""}.
25251 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
25252 Number of items to display in atom feeds view.
25254 Defaults to @samp{10}.
25258 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
25259 Number of entries to list per page in "log" view.
25261 Defaults to @samp{50}.
25265 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
25266 Number of commit message characters to display in "log" view.
25268 Defaults to @samp{80}.
25272 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
25273 Specifies the number of entries to list per page on the repository index
25276 Defaults to @samp{50}.
25280 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
25281 Specifies the maximum number of repo description characters to display
25282 on the repository index page.
25284 Defaults to @samp{80}.
25288 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
25289 Specifies the maximum size of a blob to display HTML for in KBytes.
25291 Defaults to @samp{0}.
25295 @deftypevr {@code{cgit-configuration} parameter} string max-stats
25296 Maximum statistics period. Valid values are @samp{week},@samp{month},
25297 @samp{quarter} and @samp{year}.
25299 Defaults to @samp{""}.
25303 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
25304 Mimetype for the specified filename extension.
25306 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
25307 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
25308 "image/png") (svg "image/svg+xml"))}.
25312 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
25313 Specifies the file to use for automatic mimetype lookup.
25315 Defaults to @samp{""}.
25319 @deftypevr {@code{cgit-configuration} parameter} string module-link
25320 Text which will be used as the formatstring for a hyperlink when a
25321 submodule is printed in a directory listing.
25323 Defaults to @samp{""}.
25327 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
25328 If set to the value @samp{#t} caching will be disabled.
25330 Defaults to @samp{#f}.
25334 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
25335 If set to @samp{#t} showing full author email addresses will be
25338 Defaults to @samp{#f}.
25342 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
25343 Flag which, when set to @samp{#t}, will make cgit omit the standard
25344 header on all pages.
25346 Defaults to @samp{#f}.
25350 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
25351 A list of subdirectories inside of @code{repository-directory}, relative
25352 to it, that should loaded as Git repositories. An empty list means that
25353 all subdirectories will be loaded.
25355 Defaults to @samp{()}.
25359 @deftypevr {@code{cgit-configuration} parameter} file-object readme
25360 Text which will be used as default value for @code{cgit-repo-readme}.
25362 Defaults to @samp{""}.
25366 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
25367 If set to @code{#t} and @code{repository-directory} is enabled, if any
25368 repositories are found with a suffix of @code{.git}, this suffix will be
25369 removed for the URL and name.
25371 Defaults to @samp{#f}.
25375 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
25376 Maximum number of files to consider when detecting renames.
25378 Defaults to @samp{-1}.
25382 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
25383 The way in which repositories in each section are sorted.
25385 Defaults to @samp{""}.
25389 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
25390 Text used as content for the @code{robots} meta-tag.
25392 Defaults to @samp{("noindex" "nofollow")}.
25396 @deftypevr {@code{cgit-configuration} parameter} string root-desc
25397 Text printed below the heading on the repository index page.
25399 Defaults to @samp{"a fast webinterface for the git dscm"}.
25403 @deftypevr {@code{cgit-configuration} parameter} string root-readme
25404 The content of the file specified with this option will be included
25405 verbatim below the ``about'' link on the repository index page.
25407 Defaults to @samp{""}.
25411 @deftypevr {@code{cgit-configuration} parameter} string root-title
25412 Text printed as heading on the repository index page.
25414 Defaults to @samp{""}.
25418 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
25419 If set to @samp{#t} and repository-directory is enabled,
25420 repository-directory will recurse into directories whose name starts
25421 with a period. Otherwise, repository-directory will stay away from such
25422 directories, considered as ``hidden''. Note that this does not apply to
25423 the @file{.git} directory in non-bare repos.
25425 Defaults to @samp{#f}.
25429 @deftypevr {@code{cgit-configuration} parameter} list snapshots
25430 Text which specifies the default set of snapshot formats that cgit
25431 generates links for.
25433 Defaults to @samp{()}.
25437 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
25438 Name of the directory to scan for repositories (represents
25441 Defaults to @samp{"/srv/git"}.
25445 @deftypevr {@code{cgit-configuration} parameter} string section
25446 The name of the current repository section - all repositories defined
25447 after this option will inherit the current section name.
25449 Defaults to @samp{""}.
25453 @deftypevr {@code{cgit-configuration} parameter} string section-sort
25454 Flag which, when set to @samp{1}, will sort the sections on the
25455 repository listing by name.
25457 Defaults to @samp{""}.
25461 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
25462 A number which, if defined prior to repository-directory, specifies how
25463 many path elements from each repo path to use as a default section name.
25465 Defaults to @samp{0}.
25469 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
25470 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
25473 Defaults to @samp{#f}.
25477 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
25478 Specifies a command which will be invoked to format plaintext blobs in
25481 Defaults to @samp{""}.
25485 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
25486 Specifies the number of branches to display in the repository ``summary''
25489 Defaults to @samp{10}.
25493 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
25494 Specifies the number of log entries to display in the repository
25497 Defaults to @samp{10}.
25501 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
25502 Specifies the number of tags to display in the repository ``summary''
25505 Defaults to @samp{10}.
25509 @deftypevr {@code{cgit-configuration} parameter} string strict-export
25510 Filename which, if specified, needs to be present within the repository
25511 for cgit to allow access to that repository.
25513 Defaults to @samp{""}.
25517 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
25518 URL which, if specified, will be used as root for all cgit links.
25520 Defaults to @samp{"/"}.
25524 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
25525 A list of @dfn{cgit-repo} records to use with config.
25527 Defaults to @samp{()}.
25529 Available @code{repository-cgit-configuration} fields are:
25531 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
25532 A mask of snapshot formats for this repo that cgit generates links for,
25533 restricted by the global @code{snapshots} setting.
25535 Defaults to @samp{()}.
25539 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
25540 Override the default @code{source-filter}.
25542 Defaults to @samp{""}.
25546 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
25547 The relative URL used to access the repository.
25549 Defaults to @samp{""}.
25553 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
25554 Override the default @code{about-filter}.
25556 Defaults to @samp{""}.
25560 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
25561 Flag which, when set to @samp{age}, enables date ordering in the branch
25562 ref list, and when set to @samp{name} enables ordering by branch name.
25564 Defaults to @samp{""}.
25568 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
25569 A list of URLs which can be used to clone repo.
25571 Defaults to @samp{()}.
25575 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
25576 Override the default @code{commit-filter}.
25578 Defaults to @samp{""}.
25582 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
25583 Flag which, when set to @samp{date}, enables strict date ordering in the
25584 commit log, and when set to @samp{topo} enables strict topological
25587 Defaults to @samp{""}.
25591 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
25592 The name of the default branch for this repository. If no such branch
25593 exists in the repository, the first branch name (when sorted) is used as
25594 default instead. By default branch pointed to by HEAD, or ``master'' if
25595 there is no suitable HEAD.
25597 Defaults to @samp{""}.
25601 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
25602 The value to show as repository description.
25604 Defaults to @samp{""}.
25608 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
25609 The value to show as repository homepage.
25611 Defaults to @samp{""}.
25615 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
25616 Override the default @code{email-filter}.
25618 Defaults to @samp{""}.
25622 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
25623 A flag which can be used to disable the global setting
25624 @code{enable-commit-graph?}.
25626 Defaults to @samp{disabled}.
25630 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
25631 A flag which can be used to disable the global setting
25632 @code{enable-log-filecount?}.
25634 Defaults to @samp{disabled}.
25638 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
25639 A flag which can be used to disable the global setting
25640 @code{enable-log-linecount?}.
25642 Defaults to @samp{disabled}.
25646 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
25647 Flag which, when set to @code{#t}, will make cgit display remote
25648 branches in the summary and refs views.
25650 Defaults to @samp{disabled}.
25654 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
25655 A flag which can be used to override the global setting
25656 @code{enable-subject-links?}.
25658 Defaults to @samp{disabled}.
25662 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
25663 A flag which can be used to override the global setting
25664 @code{enable-html-serving?}.
25666 Defaults to @samp{disabled}.
25670 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
25671 Flag which, when set to @code{#t}, hides the repository from the
25674 Defaults to @samp{#f}.
25678 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
25679 Flag which, when set to @samp{#t}, ignores the repository.
25681 Defaults to @samp{#f}.
25685 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
25686 URL which specifies the source of an image which will be used as a logo
25687 on this repo’s pages.
25689 Defaults to @samp{""}.
25693 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
25694 URL loaded when clicking on the cgit logo image.
25696 Defaults to @samp{""}.
25700 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
25701 Override the default @code{owner-filter}.
25703 Defaults to @samp{""}.
25707 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
25708 Text which will be used as the formatstring for a hyperlink when a
25709 submodule is printed in a directory listing. The arguments for the
25710 formatstring are the path and SHA1 of the submodule commit.
25712 Defaults to @samp{""}.
25716 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
25717 Text which will be used as the formatstring for a hyperlink when a
25718 submodule with the specified subdirectory path is printed in a directory
25721 Defaults to @samp{()}.
25725 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
25726 Override the default maximum statistics period.
25728 Defaults to @samp{""}.
25732 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
25733 The value to show as repository name.
25735 Defaults to @samp{""}.
25739 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
25740 A value used to identify the owner of the repository.
25742 Defaults to @samp{""}.
25746 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
25747 An absolute path to the repository directory.
25749 Defaults to @samp{""}.
25753 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
25754 A path (relative to repo) which specifies a file to include verbatim as
25755 the ``About'' page for this repo.
25757 Defaults to @samp{""}.
25761 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
25762 The name of the current repository section - all repositories defined
25763 after this option will inherit the current section name.
25765 Defaults to @samp{""}.
25769 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
25770 Extra options will be appended to cgitrc file.
25772 Defaults to @samp{()}.
25778 @deftypevr {@code{cgit-configuration} parameter} list extra-options
25779 Extra options will be appended to cgitrc file.
25781 Defaults to @samp{()}.
25786 @c %end of fragment
25788 However, it could be that you just want to get a @code{cgitrc} up and
25789 running. In that case, you can pass an @code{opaque-cgit-configuration}
25790 as a record to @code{cgit-service-type}. As its name indicates, an
25791 opaque configuration does not have easy reflective capabilities.
25793 Available @code{opaque-cgit-configuration} fields are:
25795 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
25799 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
25800 The contents of the @code{cgitrc}, as a string.
25803 For example, if your @code{cgitrc} is just the empty string, you
25804 could instantiate a cgit service like this:
25807 (service cgit-service-type
25808 (opaque-cgit-configuration
25812 @subsubheading Gitolite Service
25814 @cindex Gitolite service
25815 @cindex Git, hosting
25816 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
25817 repositories on a central server.
25819 Gitolite can handle multiple repositories and users, and supports flexible
25820 configuration of the permissions for the users on the repositories.
25822 The following example will configure Gitolite using the default @code{git}
25823 user, and the provided SSH public key.
25826 (service gitolite-service-type
25827 (gitolite-configuration
25828 (admin-pubkey (plain-file
25830 "ssh-rsa AAAA... guix@@example.com"))))
25833 Gitolite is configured through a special admin repository which you can clone,
25834 for example, if you setup Gitolite on @code{example.com}, you would run the
25835 following command to clone the admin repository.
25838 git clone git@@example.com:gitolite-admin
25841 When the Gitolite service is activated, the provided @code{admin-pubkey} will
25842 be inserted in to the @file{keydir} directory in the gitolite-admin
25843 repository. If this results in a change in the repository, it will be
25844 committed using the message ``gitolite setup by GNU Guix''.
25846 @deftp {Data Type} gitolite-configuration
25847 Data type representing the configuration for @code{gitolite-service-type}.
25850 @item @code{package} (default: @var{gitolite})
25851 Gitolite package to use.
25853 @item @code{user} (default: @var{git})
25854 User to use for Gitolite. This will be user that you use when accessing
25857 @item @code{group} (default: @var{git})
25858 Group to use for Gitolite.
25860 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
25861 Directory in which to store the Gitolite configuration and repositories.
25863 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
25864 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
25865 representing the configuration for Gitolite.
25867 @item @code{admin-pubkey} (default: @var{#f})
25868 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
25869 setup Gitolite. This will be inserted in to the @file{keydir} directory
25870 within the gitolite-admin repository.
25872 To specify the SSH key as a string, use the @code{plain-file} function.
25875 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
25881 @deftp {Data Type} gitolite-rc-file
25882 Data type representing the Gitolite RC file.
25885 @item @code{umask} (default: @code{#o0077})
25886 This controls the permissions Gitolite sets on the repositories and their
25889 A value like @code{#o0027} will give read access to the group used by Gitolite
25890 (by default: @code{git}). This is necessary when using Gitolite with software
25891 like cgit or gitweb.
25893 @item @code{git-config-keys} (default: @code{""})
25894 Gitolite allows you to set git config values using the @samp{config} keyword. This
25895 setting allows control over the config keys to accept.
25897 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
25898 Set the role names allowed to be used by users running the perms command.
25900 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
25901 This setting controls the commands and features to enable within Gitolite.
25907 @node Game Services
25908 @subsection Game Services
25910 @subsubheading The Battle for Wesnoth Service
25912 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
25913 based tactical strategy game, with several single player campaigns, and
25914 multiplayer games (both networked and local).
25916 @defvar {Scheme Variable} wesnothd-service-type
25917 Service type for the wesnothd service. Its value must be a
25918 @code{wesnothd-configuration} object. To run wesnothd in the default
25919 configuration, instantiate it as:
25922 (service wesnothd-service-type)
25926 @deftp {Data Type} wesnothd-configuration
25927 Data type representing the configuration of @command{wesnothd}.
25930 @item @code{package} (default: @code{wesnoth-server})
25931 The wesnoth server package to use.
25933 @item @code{port} (default: @code{15000})
25934 The port to bind the server to.
25939 @node PAM Mount Service
25940 @subsection PAM Mount Service
25943 The @code{(gnu services pam-mount)} module provides a service allowing
25944 users to mount volumes when they log in. It should be able to mount any
25945 volume format supported by the system.
25947 @defvar {Scheme Variable} pam-mount-service-type
25948 Service type for PAM Mount support.
25951 @deftp {Data Type} pam-mount-configuration
25952 Data type representing the configuration of PAM Mount.
25954 It takes the following parameters:
25958 The configuration rules that will be used to generate
25959 @file{/etc/security/pam_mount.conf.xml}.
25961 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
25962 Guile Reference Manual}), and the the default ones don't mount anything
25963 for anyone at login:
25966 `((debug (@@ (enable "0")))
25967 (mntoptions (@@ (allow ,(string-join
25968 '("nosuid" "nodev" "loop"
25969 "encryption" "fsck" "nonempty"
25970 "allow_root" "allow_other")
25972 (mntoptions (@@ (require "nosuid,nodev")))
25973 (logout (@@ (wait "0")
25977 (mkmountpoint (@@ (enable "1")
25981 Some @code{volume} elements must be added to automatically mount volumes
25982 at login. Here's an example allowing the user @code{alice} to mount her
25983 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
25984 the partition where he stores his data:
25987 (define pam-mount-rules
25988 `((debug (@@ (enable "0")))
25989 (volume (@@ (user "alice")
25992 (mountpoint "/home/alice")))
25993 (volume (@@ (user "bob")
25996 (mountpoint "/home/bob/data")
25997 (options "defaults,autodefrag,compress")))
25998 (mntoptions (@@ (allow ,(string-join
25999 '("nosuid" "nodev" "loop"
26000 "encryption" "fsck" "nonempty"
26001 "allow_root" "allow_other")
26003 (mntoptions (@@ (require "nosuid,nodev")))
26004 (logout (@@ (wait "0")
26008 (mkmountpoint (@@ (enable "1")
26009 (remove "true")))))
26011 (service pam-mount-service-type
26012 (pam-mount-configuration
26013 (rules pam-mount-rules)))
26016 The complete list of possible options can be found in the man page for
26017 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
26022 @node Guix Services
26023 @subsection Guix Services
26025 @subsubheading Guix Data Service
26026 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
26027 and provides data about GNU Guix. This includes information about
26028 packages, derivations and lint warnings.
26030 The data is stored in a PostgreSQL database, and available through a web
26033 @defvar {Scheme Variable} guix-data-service-type
26034 Service type for the Guix Data Service. Its value must be a
26035 @code{guix-data-service-configuration} object. The service optionally
26036 extends the getmail service, as the guix-commits mailing list is used to
26037 find out about changes in the Guix git repository.
26040 @deftp {Data Type} guix-data-service-configuration
26041 Data type representing the configuration of the Guix Data Service.
26044 @item @code{package} (default: @code{guix-data-service})
26045 The Guix Data Service package to use.
26047 @item @code{user} (default: @code{"guix-data-service"})
26048 The system user to run the service as.
26050 @item @code{group} (default: @code{"guix-data-service"})
26051 The system group to run the service as.
26053 @item @code{port} (default: @code{8765})
26054 The port to bind the web service to.
26056 @item @code{host} (default: @code{"127.0.0.1"})
26057 The host to bind the web service to.
26059 @item @code{getmail-idle-mailboxes} (default: @code{#f})
26060 If set, this is the list of mailboxes that the getmail service will be
26061 configured to listen to.
26063 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
26064 If set, this is the @code{getmail-retriever-configuration} object with
26065 which to configure getmail to fetch mail from the guix-commits mailing
26068 @item @code{extra-options} (default: @var{'()})
26069 Extra command line options for @code{guix-data-service}.
26071 @item @code{extra-process-jobs-options} (default: @var{'()})
26072 Extra command line options for @code{guix-data-service-process-jobs}.
26077 @node Linux Services
26078 @subsection Linux Services
26081 @cindex out of memory killer
26083 @cindex early out of memory daemon
26084 @subsubheading Early OOM Service
26086 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
26087 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
26088 space and provides a more responsive and configurable alternative to the
26089 in-kernel OOM killer. It is useful to prevent the system from becoming
26090 unresponsive when it runs out of memory.
26092 @deffn {Scheme Variable} earlyoom-service-type
26093 The service type for running @command{earlyoom}, the Early OOM daemon.
26094 Its value must be a @code{earlyoom-configuration} object, described
26095 below. The service can be instantiated in its default configuration
26099 (service earlyoom-service-type)
26103 @deftp {Data Type} earlyoom-configuration
26104 This is the configuration record for the @code{earlyoom-service-type}.
26107 @item @code{earlyoom} (default: @var{earlyoom})
26108 The Earlyoom package to use.
26110 @item @code{minimum-available-memory} (default: @code{10})
26111 The threshold for the minimum @emph{available} memory, in percentages.
26113 @item @code{minimum-free-swap} (default: @code{10})
26114 The threshold for the minimum free swap memory, in percentages.
26116 @item @code{prefer-regexp} (default: @code{#f})
26117 A regular expression (as a string) to match the names of the processes
26118 that should be preferably killed.
26120 @item @code{avoid-regexp} (default: @code{#f})
26121 A regular expression (as a string) to match the names of the processes
26122 that should @emph{not} be killed.
26124 @item @code{memory-report-interval} (default: @code{0})
26125 The interval in seconds at which a memory report is printed. It is
26126 disabled by default.
26128 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
26129 A boolean indicating whether the positive adjustments set in
26130 @file{/proc/*/oom_score_adj}.
26132 @item @code{show-debug-messages?} (default: @code{#f})
26133 A boolean indicating whether debug messages should be printed. The logs
26134 are saved at @file{/var/log/earlyoom.log}.
26136 @item @code{send-notification-command} (default: @code{#f})
26137 This can be used to provide a custom command used for sending
26143 @cindex kernel module loader
26144 @subsubheading Kernel Module Loader Service
26146 The kernel module loader service allows one to load loadable kernel
26147 modules at boot. This is especially useful for modules that don't
26148 autoload and need to be manually loaded, as it's the case with
26151 @deffn {Scheme Variable} kernel-module-loader-service-type
26152 The service type for loading loadable kernel modules at boot with
26153 @command{modprobe}. Its value must be a list of strings representing
26154 module names. For example loading the drivers provided by
26155 @code{ddcci-driver-linux}, in debugging mode by passing some module
26156 parameters, can be done as follow:
26159 (use-modules (gnu) (gnu services))
26160 (use-package-modules linux)
26161 (use-service-modules linux)
26163 (define ddcci-config
26164 (plain-file "ddcci.conf"
26165 "options ddcci dyndbg delay=120"))
26169 (services (cons* (service kernel-module-loader-service-type
26170 '("ddcci" "ddcci_backlight"))
26171 (simple-service 'ddcci-config etc-service-type
26172 (list `("modprobe.d/ddcci.conf"
26175 (kernel-loadable-modules (list ddcci-driver-linux)))
26179 @node Hurd Services
26180 @subsection Hurd Services
26182 @defvr {Scheme Variable} hurd-console-service-type
26183 This service starts the fancy @code{VGA} console client on the Hurd.
26185 The service's value is a @code{hurd-console-configuration} record.
26188 @deftp {Data Type} hurd-console-configuration
26189 This is the data type representing the configuration for the
26190 hurd-console-service.
26193 @item @code{hurd} (default: @var{hurd})
26194 The Hurd package to use.
26198 @defvr {Scheme Variable} hurd-getty-service-type
26199 This service starts a tty using the Hurd @code{getty} program.
26201 The service's value is a @code{hurd-getty-configuration} record.
26204 @deftp {Data Type} hurd-getty-configuration
26205 This is the data type representing the configuration for the
26206 hurd-getty-service.
26209 @item @code{hurd} (default: @var{hurd})
26210 The Hurd package to use.
26213 The name of the console this Getty runs on---e.g., @code{"tty1"}.
26215 @item @code{baud-rate} (default: @code{38400})
26216 An integer specifying the baud rate of the tty.
26221 @node Miscellaneous Services
26222 @subsection Miscellaneous Services
26224 @cindex fingerprint
26225 @subsubheading Fingerprint Service
26227 The @code{(gnu services authentication)} module provides a DBus service to
26228 read and identify fingerprints via a fingerprint sensor.
26230 @defvr {Scheme Variable} fprintd-service-type
26231 The service type for @command{fprintd}, which provides the fingerprint
26232 reading capability.
26235 (service fprintd-service-type)
26240 @subsubheading System Control Service
26242 The @code{(gnu services sysctl)} provides a service to configure kernel
26243 parameters at boot.
26245 @defvr {Scheme Variable} sysctl-service-type
26246 The service type for @command{sysctl}, which modifies kernel parameters
26247 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
26251 (service sysctl-service-type
26252 (sysctl-configuration
26253 (settings '(("net.ipv4.ip_forward" . "1")))))
26257 @deftp {Data Type} sysctl-configuration
26258 The data type representing the configuration of @command{sysctl}.
26261 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
26262 The @command{sysctl} executable to use.
26264 @item @code{settings} (default: @code{'()})
26265 An association list specifies kernel parameters and their values.
26270 @subsubheading PC/SC Smart Card Daemon Service
26272 The @code{(gnu services security-token)} module provides the following service
26273 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
26274 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
26275 manager that coordinates communications with smart card readers, smart cards
26276 and cryptographic tokens that are connected to the system.
26278 @defvr {Scheme Variable} pcscd-service-type
26279 Service type for the @command{pcscd} service. Its value must be a
26280 @code{pcscd-configuration} object. To run pcscd in the default
26281 configuration, instantiate it as:
26284 (service pcscd-service-type)
26288 @deftp {Data Type} pcscd-configuration
26289 The data type representing the configuration of @command{pcscd}.
26292 @item @code{pcsc-lite} (default: @code{pcsc-lite})
26293 The pcsc-lite package that provides pcscd.
26294 @item @code{usb-drivers} (default: @code{(list ccid)})
26295 List of packages that provide USB drivers to pcscd. Drivers are expected to be
26296 under @file{pcsc/drivers} in the store directory of the package.
26301 @subsubheading Lirc Service
26303 The @code{(gnu services lirc)} module provides the following service.
26305 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
26306 [#:device #f] [#:driver #f] [#:config-file #f] @
26307 [#:extra-options '()]
26308 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
26309 decodes infrared signals from remote controls.
26311 Optionally, @var{device}, @var{driver} and @var{config-file}
26312 (configuration file name) may be specified. See @command{lircd} manual
26315 Finally, @var{extra-options} is a list of additional command-line options
26316 passed to @command{lircd}.
26320 @subsubheading Spice Service
26322 The @code{(gnu services spice)} module provides the following service.
26324 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
26325 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
26326 that enables sharing the clipboard with a vm and setting the guest display
26327 resolution when the graphical console window resizes.
26330 @cindex inputattach
26331 @subsubheading inputattach Service
26333 @cindex tablet input, for Xorg
26334 @cindex touchscreen input, for Xorg
26335 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
26336 use input devices such as Wacom tablets, touchscreens, or joysticks with the
26337 Xorg display server.
26339 @deffn {Scheme Variable} inputattach-service-type
26340 Type of a service that runs @command{inputattach} on a device and
26341 dispatches events from it.
26344 @deftp {Data Type} inputattach-configuration
26346 @item @code{device-type} (default: @code{"wacom"})
26347 The type of device to connect to. Run @command{inputattach --help}, from the
26348 @code{inputattach} package, to see the list of supported device types.
26350 @item @code{device} (default: @code{"/dev/ttyS0"})
26351 The device file to connect to the device.
26353 @item @code{baud-rate} (default: @code{#f})
26354 Baud rate to use for the serial connection.
26355 Should be a number or @code{#f}.
26357 @item @code{log-file} (default: @code{#f})
26358 If true, this must be the name of a file to log messages to.
26362 @subsubheading Dictionary Service
26364 The @code{(gnu services dict)} module provides the following service:
26366 @defvr {Scheme Variable} dicod-service-type
26367 This is the type of the service that runs the @command{dicod} daemon, an
26368 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
26371 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
26372 Return a service that runs the @command{dicod} daemon, an implementation
26373 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
26375 The optional @var{config} argument specifies the configuration for
26376 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
26377 default it serves the GNU Collaborative International Dictionary of English.
26379 You can add @command{open localhost} to your @file{~/.dico} file to make
26380 @code{localhost} the default server for @command{dico} client
26381 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
26384 @deftp {Data Type} dicod-configuration
26385 Data type representing the configuration of dicod.
26388 @item @code{dico} (default: @var{dico})
26389 Package object of the GNU Dico dictionary server.
26391 @item @code{interfaces} (default: @var{'("localhost")})
26392 This is the list of IP addresses and ports and possibly socket file
26393 names to listen to (@pxref{Server Settings, @code{listen} directive,,
26394 dico, GNU Dico Manual}).
26396 @item @code{handlers} (default: @var{'()})
26397 List of @code{<dicod-handler>} objects denoting handlers (module instances).
26399 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
26400 List of @code{<dicod-database>} objects denoting dictionaries to be served.
26404 @deftp {Data Type} dicod-handler
26405 Data type representing a dictionary handler (module instance).
26409 Name of the handler (module instance).
26411 @item @code{module} (default: @var{#f})
26412 Name of the dicod module of the handler (instance). If it is @code{#f},
26413 the module has the same name as the handler.
26414 (@pxref{Modules,,, dico, GNU Dico Manual}).
26416 @item @code{options}
26417 List of strings or gexps representing the arguments for the module handler
26421 @deftp {Data Type} dicod-database
26422 Data type representing a dictionary database.
26426 Name of the database, will be used in DICT commands.
26428 @item @code{handler}
26429 Name of the dicod handler (module instance) used by this database
26430 (@pxref{Handlers,,, dico, GNU Dico Manual}).
26432 @item @code{complex?} (default: @var{#f})
26433 Whether the database configuration complex. The complex configuration
26434 will need a corresponding @code{<dicod-handler>} object, otherwise not.
26436 @item @code{options}
26437 List of strings or gexps representing the arguments for the database
26438 (@pxref{Databases,,, dico, GNU Dico Manual}).
26442 @defvr {Scheme Variable} %dicod-database:gcide
26443 A @code{<dicod-database>} object serving the GNU Collaborative International
26444 Dictionary of English using the @code{gcide} package.
26447 The following is an example @code{dicod-service} configuration.
26450 (dicod-service #:config
26451 (dicod-configuration
26452 (handlers (list (dicod-handler
26456 (list #~(string-append "dbdir=" #$wordnet))))))
26457 (databases (list (dicod-database
26460 (handler "wordnet")
26461 (options '("database=wn")))
26462 %dicod-database:gcide))))
26466 @subsubheading Docker Service
26468 The @code{(gnu services docker)} module provides the following services.
26470 @defvr {Scheme Variable} docker-service-type
26472 This is the type of the service that runs @url{https://www.docker.com,Docker},
26473 a daemon that can execute application bundles (sometimes referred to as
26474 ``containers'') in isolated environments.
26478 @deftp {Data Type} docker-configuration
26479 This is the data type representing the configuration of Docker and Containerd.
26483 @item @code{package} (default: @code{docker})
26484 The Docker package to use.
26486 @item @code{containerd} (default: @var{containerd})
26487 The Containerd package to use.
26489 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
26490 The Docker user-land networking proxy package to use.
26492 @item @code{enable-proxy?} (default @code{#f})
26493 Enable or disable the use of the Docker user-land networking proxy.
26495 @item @code{debug?} (default @code{#f})
26496 Enable or disable debug output.
26502 @subsubheading Auditd Service
26504 The @code{(gnu services auditd)} module provides the following service.
26506 @defvr {Scheme Variable} auditd-service-type
26508 This is the type of the service that runs
26509 @url{https://people.redhat.com/sgrubb/audit/,auditd},
26510 a daemon that tracks security-relevant information on your system.
26512 Examples of things that can be tracked:
26522 Failed login attempts
26529 @command{auditctl} from the @code{audit} package can be used in order
26530 to add or remove events to be tracked (until the next reboot).
26531 In order to permanently track events, put the command line arguments
26532 of auditctl into @file{/etc/audit/audit.rules}.
26533 @command{aureport} from the @code{audit} package can be used in order
26534 to view a report of all recorded events.
26535 The audit daemon usually logs into the directory @file{/var/log/audit}.
26539 @deftp {Data Type} auditd-configuration
26540 This is the data type representing the configuration of auditd.
26544 @item @code{audit} (default: @code{audit})
26545 The audit package to use.
26550 @defvr {Scheme Variable} singularity-service-type
26551 This is the type of the service that allows you to run
26552 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
26553 create and run application bundles (aka. ``containers''). The value for this
26554 service is the Singularity package to use.
26556 The service does not install a daemon; instead, it installs helper programs as
26557 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
26558 @command{singularity run} and similar commands.
26562 @subsubheading Nix service
26564 The @code{(gnu services nix)} module provides the following service.
26566 @defvr {Scheme Variable} nix-service-type
26568 This is the type of the service that runs build daemon of the
26569 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
26573 (use-modules (gnu))
26574 (use-service-modules nix)
26575 (use-package-modules package-management)
26579 (packages (append (list nix)
26582 (services (append (list (service nix-service-type))
26586 After @command{guix system reconfigure} configure Nix for your user:
26589 @item Add a Nix channel and update it. See
26590 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
26592 @item Create a symlink to your profile and activate Nix profile:
26596 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
26597 $ source /run/current-system/profile/etc/profile.d/nix.sh
26602 @node Setuid Programs
26603 @section Setuid Programs
26605 @cindex setuid programs
26606 Some programs need to run with ``root'' privileges, even when they are
26607 launched by unprivileged users. A notorious example is the
26608 @command{passwd} program, which users can run to change their
26609 password, and which needs to access the @file{/etc/passwd} and
26610 @file{/etc/shadow} files---something normally restricted to root, for
26611 obvious security reasons. To address that, these executables are
26612 @dfn{setuid-root}, meaning that they always run with root privileges
26613 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
26614 for more info about the setuid mechanism).
26616 The store itself @emph{cannot} contain setuid programs: that would be a
26617 security issue since any user on the system can write derivations that
26618 populate the store (@pxref{The Store}). Thus, a different mechanism is
26619 used: instead of changing the setuid bit directly on files that are in
26620 the store, we let the system administrator @emph{declare} which programs
26621 should be setuid root.
26623 The @code{setuid-programs} field of an @code{operating-system}
26624 declaration contains a list of G-expressions denoting the names of
26625 programs to be setuid-root (@pxref{Using the Configuration System}).
26626 For instance, the @command{passwd} program, which is part of the Shadow
26627 package, can be designated by this G-expression (@pxref{G-Expressions}):
26630 #~(string-append #$shadow "/bin/passwd")
26633 A default set of setuid programs is defined by the
26634 @code{%setuid-programs} variable of the @code{(gnu system)} module.
26636 @defvr {Scheme Variable} %setuid-programs
26637 A list of G-expressions denoting common programs that are setuid-root.
26639 The list includes commands such as @command{passwd}, @command{ping},
26640 @command{su}, and @command{sudo}.
26643 Under the hood, the actual setuid programs are created in the
26644 @file{/run/setuid-programs} directory at system activation time. The
26645 files in this directory refer to the ``real'' binaries, which are in the
26648 @node X.509 Certificates
26649 @section X.509 Certificates
26651 @cindex HTTPS, certificates
26652 @cindex X.509 certificates
26654 Web servers available over HTTPS (that is, HTTP over the transport-layer
26655 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
26656 that the client can then use to @emph{authenticate} the server. To do
26657 that, clients verify that the server's certificate is signed by a
26658 so-called @dfn{certificate authority} (CA). But to verify the CA's
26659 signature, clients must have first acquired the CA's certificate.
26661 Web browsers such as GNU@tie{}IceCat include their own set of CA
26662 certificates, such that they are able to verify CA signatures
26665 However, most other programs that can talk HTTPS---@command{wget},
26666 @command{git}, @command{w3m}, etc.---need to be told where CA
26667 certificates can be found.
26669 @cindex @code{nss-certs}
26670 In Guix, this is done by adding a package that provides certificates
26671 to the @code{packages} field of the @code{operating-system} declaration
26672 (@pxref{operating-system Reference}). Guix includes one such package,
26673 @code{nss-certs}, which is a set of CA certificates provided as part of
26674 Mozilla's Network Security Services.
26676 Note that it is @emph{not} part of @code{%base-packages}, so you need to
26677 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
26678 most applications and libraries look for certificates by default, points
26679 to the certificates installed globally.
26681 Unprivileged users, including users of Guix on a foreign distro,
26682 can also install their own certificate package in
26683 their profile. A number of environment variables need to be defined so
26684 that applications and libraries know where to find them. Namely, the
26685 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
26686 variables. Some applications add their own environment variables; for
26687 instance, the Git version control system honors the certificate bundle
26688 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
26689 would typically run something like:
26692 guix install nss-certs
26693 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
26694 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
26695 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
26698 As another example, R requires the @env{CURL_CA_BUNDLE} environment
26699 variable to point to a certificate bundle, so you would have to run
26700 something like this:
26703 guix install nss-certs
26704 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
26707 For other applications you may want to look up the required environment
26708 variable in the relevant documentation.
26711 @node Name Service Switch
26712 @section Name Service Switch
26714 @cindex name service switch
26716 The @code{(gnu system nss)} module provides bindings to the
26717 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
26718 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
26719 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
26720 extended with new ``name'' lookup methods for system databases, which
26721 includes host names, service names, user accounts, and more (@pxref{Name
26722 Service Switch, System Databases and Name Service Switch,, libc, The GNU
26723 C Library Reference Manual}).
26725 The NSS configuration specifies, for each system database, which lookup
26726 method is to be used, and how the various methods are chained
26727 together---for instance, under which circumstances NSS should try the
26728 next method in the list. The NSS configuration is given in the
26729 @code{name-service-switch} field of @code{operating-system} declarations
26730 (@pxref{operating-system Reference, @code{name-service-switch}}).
26733 @cindex .local, host name lookup
26734 As an example, the declaration below configures the NSS to use the
26735 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
26736 back-end}, which supports host name lookups over multicast DNS (mDNS)
26737 for host names ending in @code{.local}:
26740 (name-service-switch
26741 (hosts (list %files ;first, check /etc/hosts
26743 ;; If the above did not succeed, try
26744 ;; with 'mdns_minimal'.
26746 (name "mdns_minimal")
26748 ;; 'mdns_minimal' is authoritative for
26749 ;; '.local'. When it returns "not found",
26750 ;; no need to try the next methods.
26751 (reaction (lookup-specification
26752 (not-found => return))))
26754 ;; Then fall back to DNS.
26758 ;; Finally, try with the "full" 'mdns'.
26763 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
26764 contains this configuration, so you will not have to type it if all you
26765 want is to have @code{.local} host lookup working.
26767 Note that, in this case, in addition to setting the
26768 @code{name-service-switch} of the @code{operating-system} declaration,
26769 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
26770 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
26771 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
26772 to the name service cache daemon (@pxref{Base Services,
26773 @code{nscd-service}}).
26775 For convenience, the following variables provide typical NSS
26778 @defvr {Scheme Variable} %default-nss
26779 This is the default name service switch configuration, a
26780 @code{name-service-switch} object.
26783 @defvr {Scheme Variable} %mdns-host-lookup-nss
26784 This is the name service switch configuration with support for host name
26785 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
26788 The reference for name service switch configuration is given below. It
26789 is a direct mapping of the configuration file format of the C library , so
26790 please refer to the C library manual for more information (@pxref{NSS
26791 Configuration File,,, libc, The GNU C Library Reference Manual}).
26792 Compared to the configuration file format of libc NSS, it has the advantage
26793 not only of adding this warm parenthetic feel that we like, but also
26794 static checks: you will know about syntax errors and typos as soon as you
26795 run @command{guix system}.
26797 @deftp {Data Type} name-service-switch
26799 This is the data type representation the configuration of libc's name
26800 service switch (NSS). Each field below represents one of the supported
26817 The system databases handled by the NSS. Each of these fields must be a
26818 list of @code{<name-service>} objects (see below).
26822 @deftp {Data Type} name-service
26824 This is the data type representing an actual name service and the
26825 associated lookup action.
26829 A string denoting the name service (@pxref{Services in the NSS
26830 configuration,,, libc, The GNU C Library Reference Manual}).
26832 Note that name services listed here must be visible to nscd. This is
26833 achieved by passing the @code{#:name-services} argument to
26834 @code{nscd-service} the list of packages providing the needed name
26835 services (@pxref{Base Services, @code{nscd-service}}).
26838 An action specified using the @code{lookup-specification} macro
26839 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
26840 Reference Manual}). For example:
26843 (lookup-specification (unavailable => continue)
26844 (success => return))
26849 @node Initial RAM Disk
26850 @section Initial RAM Disk
26853 @cindex initial RAM disk
26854 For bootstrapping purposes, the Linux-Libre kernel is passed an
26855 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
26856 root file system as well as an initialization script. The latter is
26857 responsible for mounting the real root file system, and for loading any
26858 kernel modules that may be needed to achieve that.
26860 The @code{initrd-modules} field of an @code{operating-system}
26861 declaration allows you to specify Linux-libre kernel modules that must
26862 be available in the initrd. In particular, this is where you would list
26863 modules needed to actually drive the hard disk where your root partition
26864 is---although the default value of @code{initrd-modules} should cover
26865 most use cases. For example, assuming you need the @code{megaraid_sas}
26866 module in addition to the default modules to be able to access your root
26867 file system, you would write:
26872 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
26875 @defvr {Scheme Variable} %base-initrd-modules
26876 This is the list of kernel modules included in the initrd by default.
26879 Furthermore, if you need lower-level customization, the @code{initrd}
26880 field of an @code{operating-system} declaration allows
26881 you to specify which initrd you would like to use. The @code{(gnu
26882 system linux-initrd)} module provides three ways to build an initrd: the
26883 high-level @code{base-initrd} procedure and the low-level
26884 @code{raw-initrd} and @code{expression->initrd} procedures.
26886 The @code{base-initrd} procedure is intended to cover most common uses.
26887 For example, if you want to add a bunch of kernel modules to be loaded
26888 at boot time, you can define the @code{initrd} field of the operating
26889 system declaration like this:
26892 (initrd (lambda (file-systems . rest)
26893 ;; Create a standard initrd but set up networking
26894 ;; with the parameters QEMU expects by default.
26895 (apply base-initrd file-systems
26896 #:qemu-networking? #t
26900 The @code{base-initrd} procedure also handles common use cases that
26901 involves using the system as a QEMU guest, or as a ``live'' system with
26902 volatile root file system.
26904 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
26905 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
26906 such as trying to guess which kernel modules and packages should be included
26907 to the initrd. An example use of @code{raw-initrd} is when a user has
26908 a custom Linux kernel configuration and default kernel modules included by
26909 @code{base-initrd} are not available.
26911 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
26912 honors several options passed on the Linux kernel command line
26913 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
26914 @code{-append} option of QEMU), notably:
26917 @item --load=@var{boot}
26918 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
26919 program, once it has mounted the root file system.
26921 Guix uses this option to yield control to a boot program that runs the
26922 service activation programs and then spawns the GNU@tie{}Shepherd, the
26923 initialization system.
26925 @item --root=@var{root}
26926 Mount @var{root} as the root file system. @var{root} can be a device
26927 name like @code{/dev/sda1}, a file system label, or a file system UUID.
26928 When unspecified, the device name from the root file system of the
26929 operating system declaration is used.
26931 @item --system=@var{system}
26932 Have @file{/run/booted-system} and @file{/run/current-system} point to
26935 @item modprobe.blacklist=@var{modules}@dots{}
26936 @cindex module, black-listing
26937 @cindex black list, of kernel modules
26938 Instruct the initial RAM disk as well as the @command{modprobe} command
26939 (from the kmod package) to refuse to load @var{modules}. @var{modules}
26940 must be a comma-separated list of module names---e.g.,
26941 @code{usbkbd,9pnet}.
26944 Start a read-eval-print loop (REPL) from the initial RAM disk before it
26945 tries to load kernel modules and to mount the root file system. Our
26946 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
26947 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
26948 Manual}, for more information on Guile's REPL.
26952 Now that you know all the features that initial RAM disks produced by
26953 @code{base-initrd} and @code{raw-initrd} provide,
26954 here is how to use it and customize it further.
26957 @cindex initial RAM disk
26958 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
26959 [#:linux-modules '()] [#:mapped-devices '()] @
26960 [#:keyboard-layout #f] @
26961 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
26962 Return a derivation that builds a raw initrd. @var{file-systems} is
26963 a list of file systems to be mounted by the initrd, possibly in addition to
26964 the root file system specified on the kernel command line via @option{--root}.
26965 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
26966 @var{mapped-devices} is a list of device mappings to realize before
26967 @var{file-systems} are mounted (@pxref{Mapped Devices}).
26968 @var{helper-packages} is a list of packages to be copied in the initrd. It may
26969 include @code{e2fsck/static} or other packages needed by the initrd to check
26970 the root file system.
26972 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26973 the desired console keyboard layout. This is done before @var{mapped-devices}
26974 are set up and before @var{file-systems} are mounted such that, should the
26975 user need to enter a passphrase or use the REPL, this happens using the
26976 intended keyboard layout.
26978 When @var{qemu-networking?} is true, set up networking with the standard QEMU
26979 parameters. When @var{virtio?} is true, load additional modules so that the
26980 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
26982 When @var{volatile-root?} is true, the root file system is writable but any changes
26986 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
26987 [#:mapped-devices '()] [#:keyboard-layout #f] @
26988 [#:qemu-networking? #f] [#:volatile-root? #f] @
26989 [#:linux-modules '()]
26990 Return as a file-like object a generic initrd, with kernel
26991 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
26992 mounted by the initrd, possibly in addition to the root file system specified
26993 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
26994 mappings to realize before @var{file-systems} are mounted.
26996 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26997 the desired console keyboard layout. This is done before @var{mapped-devices}
26998 are set up and before @var{file-systems} are mounted such that, should the
26999 user need to enter a passphrase or use the REPL, this happens using the
27000 intended keyboard layout.
27002 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
27004 The initrd is automatically populated with all the kernel modules necessary
27005 for @var{file-systems} and for the given options. Additional kernel
27006 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
27007 loaded at boot time in the order in which they appear.
27010 Needless to say, the initrds we produce and use embed a
27011 statically-linked Guile, and the initialization program is a Guile
27012 program. That gives a lot of flexibility. The
27013 @code{expression->initrd} procedure builds such an initrd, given the
27014 program to run in that initrd.
27016 @deffn {Scheme Procedure} expression->initrd @var{exp} @
27017 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
27018 Return as a file-like object a Linux initrd (a gzipped cpio archive)
27019 containing @var{guile} and that evaluates @var{exp}, a G-expression,
27020 upon booting. All the derivations referenced by @var{exp} are
27021 automatically copied to the initrd.
27024 @node Bootloader Configuration
27025 @section Bootloader Configuration
27028 @cindex boot loader
27030 The operating system supports multiple bootloaders. The bootloader is
27031 configured using @code{bootloader-configuration} declaration. All the
27032 fields of this structure are bootloader agnostic except for one field,
27033 @code{bootloader} that indicates the bootloader to be configured and
27036 Some of the bootloaders do not honor every field of
27037 @code{bootloader-configuration}. For instance, the extlinux
27038 bootloader does not support themes and thus ignores the @code{theme}
27041 @deftp {Data Type} bootloader-configuration
27042 The type of a bootloader configuration declaration.
27046 @item @code{bootloader}
27047 @cindex EFI, bootloader
27048 @cindex UEFI, bootloader
27049 @cindex BIOS, bootloader
27050 The bootloader to use, as a @code{bootloader} object. For now
27051 @code{grub-bootloader}, @code{grub-efi-bootloader},
27052 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
27054 @vindex grub-efi-bootloader
27055 @code{grub-efi-bootloader} allows to boot on modern systems using the
27056 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
27057 use if the installation image contains a @file{/sys/firmware/efi} directory
27058 when you boot it on your system.
27060 @vindex grub-bootloader
27061 @code{grub-bootloader} allows you to boot in particular Intel-based machines
27062 in ``legacy'' BIOS mode.
27064 @cindex ARM, bootloaders
27065 @cindex AArch64, bootloaders
27066 Available bootloaders are described in @code{(gnu bootloader @dots{})}
27067 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
27068 of bootloaders for a wide range of ARM and AArch64 systems, using the
27069 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
27071 @item @code{target}
27072 This is a string denoting the target onto which to install the
27075 The interpretation depends on the bootloader in question. For
27076 @code{grub-bootloader}, for example, it should be a device name understood by
27077 the bootloader @command{installer} command, such as @code{/dev/sda} or
27078 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
27079 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
27080 system, usually @file{/boot/efi}.
27082 @item @code{menu-entries} (default: @code{()})
27083 A possibly empty list of @code{menu-entry} objects (see below), denoting
27084 entries to appear in the bootloader menu, in addition to the current
27085 system entry and the entry pointing to previous system generations.
27087 @item @code{default-entry} (default: @code{0})
27088 The index of the default boot menu entry. Index 0 is for the entry of the
27091 @item @code{timeout} (default: @code{5})
27092 The number of seconds to wait for keyboard input before booting. Set to
27093 0 to boot immediately, and to -1 to wait indefinitely.
27095 @cindex keyboard layout, for the bootloader
27096 @item @code{keyboard-layout} (default: @code{#f})
27097 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
27098 layout, usually US@tie{}English (``qwerty'').
27100 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
27104 This option is currently ignored by bootloaders other than @code{grub} and
27108 @item @code{theme} (default: @var{#f})
27109 The bootloader theme object describing the theme to use. If no theme
27110 is provided, some bootloaders might use a default theme, that's true
27113 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
27114 The output terminals used for the bootloader boot menu, as a list of
27115 symbols. GRUB accepts the values: @code{console}, @code{serial},
27116 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
27117 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
27118 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
27119 configuration,,, grub,GNU GRUB manual}).
27121 @item @code{terminal-inputs} (default: @code{'()})
27122 The input terminals used for the bootloader boot menu, as a list of
27123 symbols. For GRUB, the default is the native platform terminal as
27124 determined at run-time. GRUB accepts the values: @code{console},
27125 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
27126 @code{usb_keyboard}. This field corresponds to the GRUB variable
27127 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
27130 @item @code{serial-unit} (default: @code{#f})
27131 The serial unit used by the bootloader, as an integer from 0 to 3.
27132 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
27133 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
27135 @item @code{serial-speed} (default: @code{#f})
27136 The speed of the serial interface, as an integer. For GRUB, the
27137 default value is chosen at run-time; currently GRUB chooses
27138 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
27145 Should you want to list additional boot menu entries @i{via} the
27146 @code{menu-entries} field above, you will need to create them with the
27147 @code{menu-entry} form. For example, imagine you want to be able to
27148 boot another distro (hard to imagine!), you can define a menu entry
27153 (label "The Other Distro")
27154 (linux "/boot/old/vmlinux-2.6.32")
27155 (linux-arguments '("root=/dev/sda2"))
27156 (initrd "/boot/old/initrd"))
27161 @deftp {Data Type} menu-entry
27162 The type of an entry in the bootloader menu.
27167 The label to show in the menu---e.g., @code{"GNU"}.
27169 @item @code{linux} (default: @code{#f})
27170 The Linux kernel image to boot, for example:
27173 (file-append linux-libre "/bzImage")
27176 For GRUB, it is also possible to specify a device explicitly in the
27177 file path using GRUB's device naming convention (@pxref{Naming
27178 convention,,, grub, GNU GRUB manual}), for example:
27181 "(hd0,msdos1)/boot/vmlinuz"
27184 If the device is specified explicitly as above, then the @code{device}
27185 field is ignored entirely.
27187 @item @code{linux-arguments} (default: @code{()})
27188 The list of extra Linux kernel command-line arguments---e.g.,
27189 @code{("console=ttyS0")}.
27191 @item @code{initrd} (default: @code{#f})
27192 A G-Expression or string denoting the file name of the initial RAM disk
27193 to use (@pxref{G-Expressions}).
27195 @item @code{device} (default: @code{#f})
27196 The device where the kernel and initrd are to be found---i.e., for GRUB,
27197 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
27199 This may be a file system label (a string), a file system UUID (a
27200 bytevector, @pxref{File Systems}), or @code{#f}, in which case
27201 the bootloader will search the device containing the file specified by
27202 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
27203 must @emph{not} be an OS device name such as @file{/dev/sda1}.
27205 @item @code{multiboot-kernel} (default: @code{#f})
27206 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
27207 manual}). When this field is set, a Multiboot menu-entry is generated.
27211 (file-append mach "/boot/gnumach")
27214 @item @code{multiboot-arguments} (default: @code{()})
27215 The list of extra command-line arguments for the multiboot-kernel.
27217 @item @code{multiboot-modules} (default: @code{()})
27218 The list of commands for loading Multiboot modules. For example:
27221 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
27223 (list (file-append libc "/lib/ld.so.1") "exec"
27233 @c FIXME: Write documentation once it's stable.
27234 For now only GRUB has theme support. GRUB themes are created using
27235 the @code{grub-theme} form, which is not fully documented yet.
27237 @deftp {Data Type} grub-theme
27238 Data type representing the configuration of the GRUB theme.
27241 @item @code{gfxmode} (default: @code{'("auto")})
27242 The GRUB @code{gfxmode} to set (a list of screen resolution strings, see
27243 @pxref{gfxmode,,, grub, GNU GRUB manual}).
27247 @deffn {Scheme Procedure} grub-theme
27248 Return the default GRUB theme used by the operating system if no
27249 @code{theme} field is specified in @code{bootloader-configuration}
27252 It comes with a fancy background image displaying the GNU and Guix
27256 For example, to override the default resolution, you may use something
27261 (bootloader-configuration
27264 (inherit (grub-theme))
27265 (gfxmode '("1024x786x32" "auto"))))))
27268 @node Invoking guix system
27269 @section Invoking @code{guix system}
27271 Once you have written an operating system declaration as seen in the
27272 previous section, it can be @dfn{instantiated} using the @command{guix
27273 system} command. The synopsis is:
27276 guix system @var{options}@dots{} @var{action} @var{file}
27279 @var{file} must be the name of a file containing an
27280 @code{operating-system} declaration. @var{action} specifies how the
27281 operating system is instantiated. Currently the following values are
27286 Display available service type definitions that match the given regular
27287 expressions, sorted by relevance:
27293 $ guix system search console
27294 name: console-fonts
27295 location: gnu/services/base.scm:806:2
27296 extends: shepherd-root
27297 description: Install the given fonts on the specified ttys (fonts are per
27298 + virtual console on GNU/Linux). The value of this service is a list of
27299 + tty/font pairs. The font can be the name of a font provided by the `kbd'
27300 + package or any valid argument to `setfont', as in this example:
27302 + '(("tty1" . "LatGrkCyr-8x16")
27303 + ("tty2" . (file-append
27305 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
27306 + ("tty3" . (file-append
27308 + "/share/consolefonts/ter-132n"))) ; for HDPI
27312 location: gnu/services/base.scm:1190:2
27313 extends: shepherd-root
27314 description: Provide console login using the `mingetty' program.
27318 location: gnu/services/base.scm:860:2
27320 description: Provide a console log-in service as specified by its
27321 + configuration value, a `login-configuration' object.
27327 As for @command{guix package --search}, the result is written in
27328 @code{recutils} format, which makes it easy to filter the output
27329 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
27332 Build the operating system described in @var{file}, activate it, and
27333 switch to it@footnote{This action (and the related actions
27334 @code{switch-generation} and @code{roll-back}) are usable only on
27335 systems already running Guix System.}.
27338 @c The paragraph below refers to the problem discussed at
27339 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
27340 It is highly recommended to run @command{guix pull} once before you run
27341 @command{guix system reconfigure} for the first time (@pxref{Invoking
27342 guix pull}). Failing to do that you would see an older version of Guix
27343 once @command{reconfigure} has completed.
27346 This effects all the configuration specified in @var{file}: user
27347 accounts, system services, global package list, setuid programs, etc.
27348 The command starts system services specified in @var{file} that are not
27349 currently running; if a service is currently running this command will
27350 arrange for it to be upgraded the next time it is stopped (e.g.@: by
27351 @code{herd stop X} or @code{herd restart X}).
27353 This command creates a new generation whose number is one greater than
27354 the current generation (as reported by @command{guix system
27355 list-generations}). If that generation already exists, it will be
27356 overwritten. This behavior mirrors that of @command{guix package}
27357 (@pxref{Invoking guix package}).
27359 It also adds a bootloader menu entry for the new OS configuration,
27360 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
27361 entries for older configurations to a submenu, allowing you to choose
27362 an older system generation at boot time should you need it.
27364 @cindex provenance tracking, of the operating system
27365 Upon completion, the new system is deployed under
27366 @file{/run/current-system}. This directory contains @dfn{provenance
27367 meta-data}: the list of channels in use (@pxref{Channels}) and
27368 @var{file} itself, when available. This information is useful should
27369 you later want to inspect how this particular generation was built.
27371 In fact, assuming @var{file} is self-contained, you can later rebuild
27372 generation @var{n} of your operating system with:
27375 guix time-machine \
27376 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
27377 system reconfigure \
27378 /var/guix/profiles/system-@var{n}-link/configuration.scm
27381 You can think of it as some sort of built-in version control! Your
27382 system is not just a binary artifact: @emph{it carries its own source}.
27383 @xref{Service Reference, @code{provenance-service-type}}, for more
27384 information on provenance tracking.
27386 @item switch-generation
27387 @cindex generations
27388 Switch to an existing system generation. This action atomically
27389 switches the system profile to the specified system generation. It
27390 also rearranges the system's existing bootloader menu entries. It
27391 makes the menu entry for the specified system generation the default,
27392 and it moves the entries for the other generations to a submenu, if
27393 supported by the bootloader being used. The next time the system
27394 boots, it will use the specified system generation.
27396 The bootloader itself is not being reinstalled when using this
27397 command. Thus, the installed bootloader is used with an updated
27398 configuration file.
27400 The target generation can be specified explicitly by its generation
27401 number. For example, the following invocation would switch to system
27405 guix system switch-generation 7
27408 The target generation can also be specified relative to the current
27409 generation with the form @code{+N} or @code{-N}, where @code{+3} means
27410 ``3 generations ahead of the current generation,'' and @code{-1} means
27411 ``1 generation prior to the current generation.'' When specifying a
27412 negative value such as @code{-1}, you must precede it with @code{--} to
27413 prevent it from being parsed as an option. For example:
27416 guix system switch-generation -- -1
27419 Currently, the effect of invoking this action is @emph{only} to switch
27420 the system profile to an existing generation and rearrange the
27421 bootloader menu entries. To actually start using the target system
27422 generation, you must reboot after running this action. In the future,
27423 it will be updated to do the same things as @command{reconfigure},
27424 like activating and deactivating services.
27426 This action will fail if the specified generation does not exist.
27429 @cindex rolling back
27430 Switch to the preceding system generation. The next time the system
27431 boots, it will use the preceding system generation. This is the inverse
27432 of @command{reconfigure}, and it is exactly the same as invoking
27433 @command{switch-generation} with an argument of @code{-1}.
27435 Currently, as with @command{switch-generation}, you must reboot after
27436 running this action to actually start using the preceding system
27439 @item delete-generations
27440 @cindex deleting system generations
27441 @cindex saving space
27442 Delete system generations, making them candidates for garbage collection
27443 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
27446 This works in the same way as @samp{guix package --delete-generations}
27447 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
27448 arguments, all system generations but the current one are deleted:
27451 guix system delete-generations
27454 You can also select the generations you want to delete. The example below
27455 deletes all the system generations that are more than two month old:
27458 guix system delete-generations 2m
27461 Running this command automatically reinstalls the bootloader with an updated
27462 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
27463 longer lists the generations that have been deleted.
27466 Build the derivation of the operating system, which includes all the
27467 configuration files and programs needed to boot and run the system.
27468 This action does not actually install anything.
27471 Populate the given directory with all the files necessary to run the
27472 operating system specified in @var{file}. This is useful for first-time
27473 installations of Guix System. For instance:
27476 guix system init my-os-config.scm /mnt
27479 copies to @file{/mnt} all the store items required by the configuration
27480 specified in @file{my-os-config.scm}. This includes configuration
27481 files, packages, and so on. It also creates other essential files
27482 needed for the system to operate correctly---e.g., the @file{/etc},
27483 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
27485 This command also installs bootloader on the target specified in
27486 @file{my-os-config}, unless the @option{--no-bootloader} option was
27490 @cindex virtual machine
27492 @anchor{guix system vm}
27493 Build a virtual machine that contains the operating system declared in
27494 @var{file}, and return a script to run that virtual machine (VM).
27497 The @code{vm} action and others below
27498 can use KVM support in the Linux-libre kernel. Specifically, if the
27499 machine has hardware virtualization support, the corresponding
27500 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
27501 must exist and be readable and writable by the user and by the
27502 build users of the daemon (@pxref{Build Environment Setup}).
27505 Arguments given to the script are passed to QEMU as in the example
27506 below, which enables networking and requests 1@tie{}GiB of RAM for the
27510 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
27513 The VM shares its store with the host system.
27515 Additional file systems can be shared between the host and the VM using
27516 the @option{--share} and @option{--expose} command-line options: the former
27517 specifies a directory to be shared with write access, while the latter
27518 provides read-only access to the shared directory.
27520 The example below creates a VM in which the user's home directory is
27521 accessible read-only, and where the @file{/exchange} directory is a
27522 read-write mapping of @file{$HOME/tmp} on the host:
27525 guix system vm my-config.scm \
27526 --expose=$HOME --share=$HOME/tmp=/exchange
27529 On GNU/Linux, the default is to boot directly to the kernel; this has
27530 the advantage of requiring only a very tiny root disk image since the
27531 store of the host can then be mounted.
27533 The @option{--full-boot} option forces a complete boot sequence, starting
27534 with the bootloader. This requires more disk space since a root image
27535 containing at least the kernel, initrd, and bootloader data files must
27536 be created. The @option{--image-size} option can be used to specify the
27539 @cindex System images, creation in various formats
27540 @cindex Creating system images in various formats
27543 @itemx docker-image
27544 Return a virtual machine, disk image, or Docker image of the operating
27545 system declared in @var{file} that stands alone. By default,
27546 @command{guix system} estimates the size of the image needed to store
27547 the system, but you can use the @option{--image-size} option to specify
27548 a value. Docker images are built to contain exactly what they need, so
27549 the @option{--image-size} option is ignored in the case of
27550 @code{docker-image}.
27552 You can specify the root file system type by using the
27553 @option{--file-system-type} option. It defaults to @code{ext4}.
27555 When using @code{vm-image}, the returned image is in qcow2 format, which
27556 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
27557 for more information on how to run the image in a virtual machine.
27559 When using @code{disk-image}, a raw disk image is produced; it can be
27560 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
27561 the device corresponding to a USB stick, one can copy the image to it
27562 using the following command:
27565 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
27568 When using @code{docker-image}, a Docker image is produced. Guix builds
27569 the image from scratch, not from a pre-existing Docker base image. As a
27570 result, it contains @emph{exactly} what you define in the operating
27571 system configuration file. You can then load the image and launch a
27572 Docker container using commands like the following:
27575 image_id="`docker load < guix-system-docker-image.tar.gz`"
27576 container_id="`docker create $image_id`"
27577 docker start $container_id
27580 This command starts a new Docker container from the specified image. It
27581 will boot the Guix system in the usual manner, which means it will
27582 start any services you have defined in the operating system
27583 configuration. You can get an interactive shell running in the container
27584 using @command{docker exec}:
27587 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
27590 Depending on what you run in the Docker container, it
27591 may be necessary to give the container additional permissions. For
27592 example, if you intend to build software using Guix inside of the Docker
27593 container, you may need to pass the @option{--privileged} option to
27594 @code{docker create}.
27596 Last, the @option{--network} option applies to @command{guix system
27597 docker-image}: it produces an image where network is supposedly shared
27598 with the host, and thus without services like nscd or NetworkManager.
27601 Return a script to run the operating system declared in @var{file}
27602 within a container. Containers are a set of lightweight isolation
27603 mechanisms provided by the kernel Linux-libre. Containers are
27604 substantially less resource-demanding than full virtual machines since
27605 the kernel, shared objects, and other resources can be shared with the
27606 host system; this also means they provide thinner isolation.
27608 Currently, the script must be run as root in order to support more than
27609 a single user and group. The container shares its store with the host
27612 As with the @code{vm} action (@pxref{guix system vm}), additional file
27613 systems to be shared between the host and container can be specified
27614 using the @option{--share} and @option{--expose} options:
27617 guix system container my-config.scm \
27618 --expose=$HOME --share=$HOME/tmp=/exchange
27622 This option requires Linux-libre 3.19 or newer.
27627 @var{options} can contain any of the common build options (@pxref{Common
27628 Build Options}). In addition, @var{options} can contain one of the
27632 @item --expression=@var{expr}
27633 @itemx -e @var{expr}
27634 Consider the operating-system @var{expr} evaluates to.
27635 This is an alternative to specifying a file which evaluates to an
27637 This is used to generate the Guix system installer @pxref{Building the
27638 Installation Image}).
27640 @item --system=@var{system}
27641 @itemx -s @var{system}
27642 Attempt to build for @var{system} instead of the host system type.
27643 This works as per @command{guix build} (@pxref{Invoking guix build}).
27647 Return the derivation file name of the given operating system without
27650 @cindex provenance tracking, of the operating system
27651 @item --save-provenance
27652 As discussed above, @command{guix system init} and @command{guix system
27653 reconfigure} always save provenance information @i{via} a dedicated
27654 service (@pxref{Service Reference, @code{provenance-service-type}}).
27655 However, other commands don't do that by default. If you wish to, say,
27656 create a virtual machine image that contains provenance information, you
27660 guix system vm-image --save-provenance config.scm
27663 That way, the resulting image will effectively ``embed its own source''
27664 in the form of meta-data in @file{/run/current-system}. With that
27665 information, one can rebuild the image to make sure it really contains
27666 what it pretends to contain; or they could use that to derive a variant
27669 @item --file-system-type=@var{type}
27670 @itemx -t @var{type}
27671 For the @code{disk-image} action, create a file system of the given
27672 @var{type} on the image.
27674 When this option is omitted, @command{guix system} uses @code{ext4}.
27676 @cindex ISO-9660 format
27677 @cindex CD image format
27678 @cindex DVD image format
27679 @option{--file-system-type=iso9660} produces an ISO-9660 image, suitable
27680 for burning on CDs and DVDs.
27682 @item --image-size=@var{size}
27683 For the @code{vm-image} and @code{disk-image} actions, create an image
27684 of the given @var{size}. @var{size} may be a number of bytes, or it may
27685 include a unit as a suffix (@pxref{Block size, size specifications,,
27686 coreutils, GNU Coreutils}).
27688 When this option is omitted, @command{guix system} computes an estimate
27689 of the image size as a function of the size of the system declared in
27694 For the @code{container} action, allow containers to access the host network,
27695 that is, do not create a network namespace.
27697 @item --root=@var{file}
27698 @itemx -r @var{file}
27699 Make @var{file} a symlink to the result, and register it as a garbage
27702 @item --skip-checks
27703 Skip pre-installation safety checks.
27705 By default, @command{guix system init} and @command{guix system
27706 reconfigure} perform safety checks: they make sure the file systems that
27707 appear in the @code{operating-system} declaration actually exist
27708 (@pxref{File Systems}), and that any Linux kernel modules that may be
27709 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
27710 RAM Disk}). Passing this option skips these tests altogether.
27713 @cindex on-error strategy
27714 @cindex error strategy
27715 @item --on-error=@var{strategy}
27716 Apply @var{strategy} when an error occurs when reading @var{file}.
27717 @var{strategy} may be one of the following:
27720 @item nothing-special
27721 Report the error concisely and exit. This is the default strategy.
27724 Likewise, but also display a backtrace.
27727 Report the error and enter Guile's debugger. From there, you can run
27728 commands such as @code{,bt} to get a backtrace, @code{,locals} to
27729 display local variable values, and more generally inspect the state of the
27730 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
27731 a list of available debugging commands.
27735 Once you have built, configured, re-configured, and re-re-configured
27736 your Guix installation, you may find it useful to list the operating
27737 system generations available on disk---and that you can choose from the
27738 bootloader boot menu:
27743 Describe the current system generation: its file name, the kernel and
27744 bootloader used, etc., as well as provenance information when available.
27746 @item list-generations
27747 List a summary of each generation of the operating system available on
27748 disk, in a human-readable way. This is similar to the
27749 @option{--list-generations} option of @command{guix package}
27750 (@pxref{Invoking guix package}).
27752 Optionally, one can specify a pattern, with the same syntax that is used
27753 in @command{guix package --list-generations}, to restrict the list of
27754 generations displayed. For instance, the following command displays
27755 generations that are up to 10 days old:
27758 $ guix system list-generations 10d
27763 The @command{guix system} command has even more to offer! The following
27764 sub-commands allow you to visualize how your system services relate to
27767 @anchor{system-extension-graph}
27770 @item extension-graph
27771 Emit in Dot/Graphviz format to standard output the @dfn{service
27772 extension graph} of the operating system defined in @var{file}
27773 (@pxref{Service Composition}, for more information on service
27779 $ guix system extension-graph @var{file} | xdot -
27782 shows the extension relations among services.
27784 @anchor{system-shepherd-graph}
27785 @item shepherd-graph
27786 Emit in Dot/Graphviz format to standard output the @dfn{dependency
27787 graph} of shepherd services of the operating system defined in
27788 @var{file}. @xref{Shepherd Services}, for more information and for an
27793 @node Invoking guix deploy
27794 @section Invoking @code{guix deploy}
27796 We've already seen @code{operating-system} declarations used to manage a
27797 machine's configuration locally. Suppose you need to configure multiple
27798 machines, though---perhaps you're managing a service on the web that's
27799 comprised of several servers. @command{guix deploy} enables you to use those
27800 same @code{operating-system} declarations to manage multiple remote hosts at
27801 once as a logical ``deployment''.
27804 The functionality described in this section is still under development
27805 and is subject to change. Get in touch with us on
27806 @email{guix-devel@@gnu.org}!
27810 guix deploy @var{file}
27813 Such an invocation will deploy the machines that the code within @var{file}
27814 evaluates to. As an example, @var{file} might contain a definition like this:
27817 ;; This is a Guix deployment of a "bare bones" setup, with
27818 ;; no X11 display server, to a machine with an SSH daemon
27819 ;; listening on localhost:2222. A configuration such as this
27820 ;; may be appropriate for virtual machine with ports
27821 ;; forwarded to the host's loopback interface.
27823 (use-service-modules networking ssh)
27824 (use-package-modules bootloaders)
27828 (host-name "gnu-deployed")
27829 (timezone "Etc/UTC")
27830 (bootloader (bootloader-configuration
27831 (bootloader grub-bootloader)
27832 (target "/dev/vda")
27833 (terminal-outputs '(console))))
27834 (file-systems (cons (file-system
27836 (device "/dev/vda1")
27838 %base-file-systems))
27840 (append (list (service dhcp-client-service-type)
27841 (service openssh-service-type
27842 (openssh-configuration
27843 (permit-root-login #t)
27844 (allow-empty-passwords? #t))))
27848 (operating-system %system)
27849 (environment managed-host-environment-type)
27850 (configuration (machine-ssh-configuration
27851 (host-name "localhost")
27852 (system "x86_64-linux")
27854 (identity "./id_rsa")
27858 The file should evaluate to a list of @var{machine} objects. This example,
27859 upon being deployed, will create a new generation on the remote system
27860 realizing the @code{operating-system} declaration @code{%system}.
27861 @code{environment} and @code{configuration} specify how the machine should be
27862 provisioned---that is, how the computing resources should be created and
27863 managed. The above example does not create any resources, as a
27864 @code{'managed-host} is a machine that is already running the Guix system and
27865 available over the network. This is a particularly simple case; a more
27866 complex deployment may involve, for example, starting virtual machines through
27867 a Virtual Private Server (VPS) provider. In such a case, a different
27868 @var{environment} type would be used.
27870 Do note that you first need to generate a key pair on the coordinator machine
27871 to allow the daemon to export signed archives of files from the store
27872 (@pxref{Invoking guix archive}).
27875 # guix archive --generate-key
27879 Each target machine must authorize the key of the master machine so that it
27880 accepts store items it receives from the coordinator:
27883 # guix archive --authorize < coordinator-public-key.txt
27886 @code{user}, in this example, specifies the name of the user account to log in
27887 as to perform the deployment. Its default value is @code{root}, but root
27888 login over SSH may be forbidden in some cases. To work around this,
27889 @command{guix deploy} can log in as an unprivileged user and employ
27890 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
27891 currently installed on the remote and can be invoked non-interactively as
27892 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
27893 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
27894 be accomplished with the following operating system configuration snippet:
27898 (gnu system)) ;for %sudoers-specification
27900 (define %user "username")
27905 (plain-file "sudoers"
27906 (string-append (plain-file-content %sudoers-specification)
27907 (format #f "~a ALL = NOPASSWD: ALL~%"
27912 For more information regarding the format of the @file{sudoers} file,
27913 consult @command{man sudoers}.
27915 @deftp {Data Type} machine
27916 This is the data type representing a single machine in a heterogeneous Guix
27920 @item @code{operating-system}
27921 The object of the operating system configuration to deploy.
27923 @item @code{environment}
27924 An @code{environment-type} describing how the machine should be provisioned.
27926 @item @code{configuration} (default: @code{#f})
27927 An object describing the configuration for the machine's @code{environment}.
27928 If the @code{environment} has a default configuration, @code{#f} may be used.
27929 If @code{#f} is used for an environment with no default configuration,
27930 however, an error will be thrown.
27934 @deftp {Data Type} machine-ssh-configuration
27935 This is the data type representing the SSH client parameters for a machine
27936 with an @code{environment} of @code{managed-host-environment-type}.
27939 @item @code{host-name}
27940 @item @code{build-locally?} (default: @code{#t})
27941 If false, system derivations will be built on the machine being deployed to.
27942 @item @code{system}
27943 The system type describing the architecture of the machine being deployed
27944 to---e.g., @code{"x86_64-linux"}.
27945 @item @code{authorize?} (default: @code{#t})
27946 If true, the coordinator's signing key will be added to the remote's ACL
27948 @item @code{port} (default: @code{22})
27949 @item @code{user} (default: @code{"root"})
27950 @item @code{identity} (default: @code{#f})
27951 If specified, the path to the SSH private key to use to authenticate with the
27954 @item @code{host-key} (default: @code{#f})
27955 This should be the SSH host key of the machine, which looks like this:
27958 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
27961 When @code{host-key} is @code{#f}, the server is authenticated against
27962 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
27968 @deftp {Data Type} digital-ocean-configuration
27969 This is the data type describing the Droplet that should be created for a
27970 machine with an @code{environment} of @code{digital-ocean-environment-type}.
27973 @item @code{ssh-key}
27974 The path to the SSH private key to use to authenticate with the remote
27975 host. In the future, this field may not exist.
27977 A list of string ``tags'' that uniquely identify the machine. Must be given
27978 such that no two machines in the deployment have the same set of tags.
27979 @item @code{region}
27980 A Digital Ocean region slug, such as @code{"nyc3"}.
27982 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
27983 @item @code{enable-ipv6?}
27984 Whether or not the droplet should be created with IPv6 networking.
27988 @node Running Guix in a VM
27989 @section Running Guix in a Virtual Machine
27991 @cindex virtual machine
27992 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
27994 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
27995 This image is a compressed image in QCOW format. You will first need to
27996 decompress with @command{xz -d}, and then you can pass it to an emulator such
27997 as QEMU (see below for details).
27999 This image boots the Xfce graphical environment and it contains some
28000 commonly-used tools. You can install more software in the image by running
28001 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
28002 also reconfigure the system based on its initial configuration file available
28003 as @file{/run/current-system/configuration.scm} (@pxref{Using the
28004 Configuration System}).
28006 Instead of using this pre-built image, one can also build their own virtual
28007 machine image using @command{guix system vm-image} (@pxref{Invoking guix
28008 system}). The returned image is in qcow2 format, which the
28009 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
28012 If you built your own image, you must copy it out of the store
28013 (@pxref{The Store}) and give yourself permission to write to the copy
28014 before you can use it. When invoking QEMU, you must choose a system
28015 emulator that is suitable for your hardware platform. Here is a minimal
28016 QEMU invocation that will boot the result of @command{guix system
28017 vm-image} on x86_64 hardware:
28020 $ qemu-system-x86_64 \
28021 -nic user,model=virtio-net-pci \
28022 -enable-kvm -m 1024 \
28023 -device virtio-blk,drive=myhd \
28024 -drive if=none,file=/tmp/qemu-image,id=myhd
28027 Here is what each of these options means:
28030 @item qemu-system-x86_64
28031 This specifies the hardware platform to emulate. This should match the
28034 @item -nic user,model=virtio-net-pci
28035 Enable the unprivileged user-mode network stack. The guest OS can
28036 access the host but not vice versa. This is the simplest way to get the
28037 guest OS online. @code{model} specifies which network device to emulate:
28038 @code{virtio-net-pci} is a special device made for virtualized operating
28039 systems and recommended for most uses. Assuming your hardware platform is
28040 x86_64, you can get a list of available NIC models by running
28041 @command{qemu-system-x86_64 -nic model=help}.
28044 If your system has hardware virtualization extensions, enabling the
28045 virtual machine support (KVM) of the Linux kernel will make things run
28048 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
28050 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
28051 which may be insufficient for some operations.
28053 @item -device virtio-blk,drive=myhd
28054 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
28055 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
28056 better performance than if it were emulating a complete disk drive. See the
28057 QEMU and KVM documentation for more info.
28059 @item -drive if=none,file=/tmp/qemu-image,id=myhd
28060 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
28061 the ``myhd'' drive.
28064 The default @command{run-vm.sh} script that is returned by an invocation of
28065 @command{guix system vm} does not add a @command{-nic user} flag by default.
28066 To get network access from within the vm add the @code{(dhcp-client-service)}
28067 to your system definition and start the VM using
28068 @command{`guix system vm config.scm` -nic user}. An important caveat of using
28069 @command{-nic user} for networking is that @command{ping} will not work, because
28070 it uses the ICMP protocol. You'll have to use a different command to check for
28071 network connectivity, for example @command{guix download}.
28073 @subsection Connecting Through SSH
28077 To enable SSH inside a VM you need to add an SSH server like
28078 @code{openssh-service-type} to your VM (@pxref{Networking Services,
28079 @code{openssh-service-type}}). In addition you need to forward the SSH port,
28080 22 by default, to the host. You can do this with
28083 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
28086 To connect to the VM you can run
28089 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
28092 The @command{-p} tells @command{ssh} the port you want to connect to.
28093 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
28094 every time you modify your @command{config.scm} file and the
28095 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
28096 connection to an unknown host every time you connect.
28098 @subsection Using @command{virt-viewer} with Spice
28100 As an alternative to the default @command{qemu} graphical client you can
28101 use the @command{remote-viewer} from the @command{virt-viewer} package. To
28102 connect pass the @command{-spice port=5930,disable-ticketing} flag to
28103 @command{qemu}. See previous section for further information on how to do this.
28105 Spice also allows you to do some nice stuff like share your clipboard with your
28106 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
28109 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
28110 -chardev spicevmc,name=vdagent,id=vdagent
28111 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
28112 name=com.redhat.spice.0
28115 You'll also need to add the @code{(spice-vdagent-service)} to your
28116 system definition (@pxref{Miscellaneous Services, Spice service}).
28118 @node Defining Services
28119 @section Defining Services
28121 The previous sections show the available services and how one can combine
28122 them in an @code{operating-system} declaration. But how do we define
28123 them in the first place? And what is a service anyway?
28126 * Service Composition:: The model for composing services.
28127 * Service Types and Services:: Types and services.
28128 * Service Reference:: API reference.
28129 * Shepherd Services:: A particular type of service.
28132 @node Service Composition
28133 @subsection Service Composition
28137 Here we define a @dfn{service} as, broadly, something that extends the
28138 functionality of the operating system. Often a service is a process---a
28139 @dfn{daemon}---started when the system boots: a secure shell server, a
28140 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
28141 whose execution can be triggered by another daemon---e.g., an FTP server
28142 started by @command{inetd} or a D-Bus service activated by
28143 @command{dbus-daemon}. Occasionally, a service does not map to a
28144 daemon. For instance, the ``account'' service collects user accounts
28145 and makes sure they exist when the system runs; the ``udev'' service
28146 collects device management rules and makes them available to the eudev
28147 daemon; the @file{/etc} service populates the @file{/etc} directory
28150 @cindex service extensions
28151 Guix system services are connected by @dfn{extensions}. For instance, the
28152 secure shell service @emph{extends} the Shepherd---the
28153 initialization system, running as PID@tie{}1---by giving it the command
28154 lines to start and stop the secure shell daemon (@pxref{Networking
28155 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
28156 service by passing it its @file{.service} specification, and extends the
28157 udev service by passing it device management rules (@pxref{Desktop
28158 Services, @code{upower-service}}); the Guix daemon service extends the
28159 Shepherd by passing it the command lines to start and stop the daemon,
28160 and extends the account service by passing it a list of required build
28161 user accounts (@pxref{Base Services}).
28163 All in all, services and their ``extends'' relations form a directed
28164 acyclic graph (DAG). If we represent services as boxes and extensions
28165 as arrows, a typical system might provide something like this:
28167 @image{images/service-graph,,5in,Typical service extension graph.}
28169 @cindex system service
28170 At the bottom, we see the @dfn{system service}, which produces the
28171 directory containing everything to run and boot the system, as returned
28172 by the @command{guix system build} command. @xref{Service Reference},
28173 to learn about the other service types shown here.
28174 @xref{system-extension-graph, the @command{guix system extension-graph}
28175 command}, for information on how to generate this representation for a
28176 particular operating system definition.
28178 @cindex service types
28179 Technically, developers can define @dfn{service types} to express these
28180 relations. There can be any number of services of a given type on the
28181 system---for instance, a system running two instances of the GNU secure
28182 shell server (lsh) has two instances of @code{lsh-service-type}, with
28183 different parameters.
28185 The following section describes the programming interface for service
28186 types and services.
28188 @node Service Types and Services
28189 @subsection Service Types and Services
28191 A @dfn{service type} is a node in the DAG described above. Let us start
28192 with a simple example, the service type for the Guix build daemon
28193 (@pxref{Invoking guix-daemon}):
28196 (define guix-service-type
28200 (list (service-extension shepherd-root-service-type guix-shepherd-service)
28201 (service-extension account-service-type guix-accounts)
28202 (service-extension activation-service-type guix-activation)))
28203 (default-value (guix-configuration))))
28207 It defines three things:
28211 A name, whose sole purpose is to make inspection and debugging easier.
28214 A list of @dfn{service extensions}, where each extension designates the
28215 target service type and a procedure that, given the parameters of the
28216 service, returns a list of objects to extend the service of that type.
28218 Every service type has at least one service extension. The only
28219 exception is the @dfn{boot service type}, which is the ultimate service.
28222 Optionally, a default value for instances of this type.
28225 In this example, @code{guix-service-type} extends three services:
28228 @item shepherd-root-service-type
28229 The @code{guix-shepherd-service} procedure defines how the Shepherd
28230 service is extended. Namely, it returns a @code{<shepherd-service>}
28231 object that defines how @command{guix-daemon} is started and stopped
28232 (@pxref{Shepherd Services}).
28234 @item account-service-type
28235 This extension for this service is computed by @code{guix-accounts},
28236 which returns a list of @code{user-group} and @code{user-account}
28237 objects representing the build user accounts (@pxref{Invoking
28240 @item activation-service-type
28241 Here @code{guix-activation} is a procedure that returns a gexp, which is
28242 a code snippet to run at ``activation time''---e.g., when the service is
28246 A service of this type is instantiated like this:
28249 (service guix-service-type
28250 (guix-configuration
28252 (use-substitutes? #f)))
28255 The second argument to the @code{service} form is a value representing
28256 the parameters of this specific service instance.
28257 @xref{guix-configuration-type, @code{guix-configuration}}, for
28258 information about the @code{guix-configuration} data type. When the
28259 value is omitted, the default value specified by
28260 @code{guix-service-type} is used:
28263 (service guix-service-type)
28266 @code{guix-service-type} is quite simple because it extends other
28267 services but is not extensible itself.
28269 @c @subsubsubsection Extensible Service Types
28271 The service type for an @emph{extensible} service looks like this:
28274 (define udev-service-type
28275 (service-type (name 'udev)
28277 (list (service-extension shepherd-root-service-type
28278 udev-shepherd-service)))
28280 (compose concatenate) ;concatenate the list of rules
28281 (extend (lambda (config rules)
28283 (($ <udev-configuration> udev initial-rules)
28284 (udev-configuration
28285 (udev udev) ;the udev package to use
28286 (rules (append initial-rules rules)))))))))
28289 This is the service type for the
28290 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
28291 management daemon}. Compared to the previous example, in addition to an
28292 extension of @code{shepherd-root-service-type}, we see two new fields:
28296 This is the procedure to @dfn{compose} the list of extensions to
28297 services of this type.
28299 Services can extend the udev service by passing it lists of rules; we
28300 compose those extensions simply by concatenating them.
28303 This procedure defines how the value of the service is @dfn{extended} with
28304 the composition of the extensions.
28306 Udev extensions are composed into a list of rules, but the udev service
28307 value is itself a @code{<udev-configuration>} record. So here, we
28308 extend that record by appending the list of rules it contains to the
28309 list of contributed rules.
28312 This is a string giving an overview of the service type. The string can
28313 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
28314 @command{guix system search} command searches these strings and displays
28315 them (@pxref{Invoking guix system}).
28318 There can be only one instance of an extensible service type such as
28319 @code{udev-service-type}. If there were more, the
28320 @code{service-extension} specifications would be ambiguous.
28322 Still here? The next section provides a reference of the programming
28323 interface for services.
28325 @node Service Reference
28326 @subsection Service Reference
28328 We have seen an overview of service types (@pxref{Service Types and
28329 Services}). This section provides a reference on how to manipulate
28330 services and service types. This interface is provided by the
28331 @code{(gnu services)} module.
28333 @deffn {Scheme Procedure} service @var{type} [@var{value}]
28334 Return a new service of @var{type}, a @code{<service-type>} object (see
28335 below). @var{value} can be any object; it represents the parameters of
28336 this particular service instance.
28338 When @var{value} is omitted, the default value specified by @var{type}
28339 is used; if @var{type} does not specify a default value, an error is
28342 For instance, this:
28345 (service openssh-service-type)
28349 is equivalent to this:
28352 (service openssh-service-type
28353 (openssh-configuration))
28356 In both cases the result is an instance of @code{openssh-service-type}
28357 with the default configuration.
28360 @deffn {Scheme Procedure} service? @var{obj}
28361 Return true if @var{obj} is a service.
28364 @deffn {Scheme Procedure} service-kind @var{service}
28365 Return the type of @var{service}---i.e., a @code{<service-type>} object.
28368 @deffn {Scheme Procedure} service-value @var{service}
28369 Return the value associated with @var{service}. It represents its
28373 Here is an example of how a service is created and manipulated:
28377 (service nginx-service-type
28378 (nginx-configuration
28380 (log-directory log-directory)
28381 (run-directory run-directory)
28382 (file config-file))))
28387 (eq? (service-kind s) nginx-service-type)
28391 The @code{modify-services} form provides a handy way to change the
28392 parameters of some of the services of a list such as
28393 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
28394 evaluates to a list of services. Of course, you could always use
28395 standard list combinators such as @code{map} and @code{fold} to do that
28396 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
28397 @code{modify-services} simply provides a more concise form for this
28400 @deffn {Scheme Syntax} modify-services @var{services} @
28401 (@var{type} @var{variable} => @var{body}) @dots{}
28403 Modify the services listed in @var{services} according to the given
28404 clauses. Each clause has the form:
28407 (@var{type} @var{variable} => @var{body})
28410 where @var{type} is a service type---e.g.,
28411 @code{guix-service-type}---and @var{variable} is an identifier that is
28412 bound within the @var{body} to the service parameters---e.g., a
28413 @code{guix-configuration} instance---of the original service of that
28416 The @var{body} should evaluate to the new service parameters, which will
28417 be used to configure the new service. This new service will replace the
28418 original in the resulting list. Because a service's service parameters
28419 are created using @code{define-record-type*}, you can write a succinct
28420 @var{body} that evaluates to the new service parameters by using the
28421 @code{inherit} feature that @code{define-record-type*} provides.
28423 @xref{Using the Configuration System}, for example usage.
28427 Next comes the programming interface for service types. This is
28428 something you want to know when writing new service definitions, but not
28429 necessarily when simply looking for ways to customize your
28430 @code{operating-system} declaration.
28432 @deftp {Data Type} service-type
28433 @cindex service type
28434 This is the representation of a @dfn{service type} (@pxref{Service Types
28439 This is a symbol, used only to simplify inspection and debugging.
28441 @item @code{extensions}
28442 A non-empty list of @code{<service-extension>} objects (see below).
28444 @item @code{compose} (default: @code{#f})
28445 If this is @code{#f}, then the service type denotes services that cannot
28446 be extended---i.e., services that do not receive ``values'' from other
28449 Otherwise, it must be a one-argument procedure. The procedure is called
28450 by @code{fold-services} and is passed a list of values collected from
28451 extensions. It may return any single value.
28453 @item @code{extend} (default: @code{#f})
28454 If this is @code{#f}, services of this type cannot be extended.
28456 Otherwise, it must be a two-argument procedure: @code{fold-services}
28457 calls it, passing it the initial value of the service as the first
28458 argument and the result of applying @code{compose} to the extension
28459 values as the second argument. It must return a value that is a valid
28460 parameter value for the service instance.
28463 @xref{Service Types and Services}, for examples.
28466 @deffn {Scheme Procedure} service-extension @var{target-type} @
28468 Return a new extension for services of type @var{target-type}.
28469 @var{compute} must be a one-argument procedure: @code{fold-services}
28470 calls it, passing it the value associated with the service that provides
28471 the extension; it must return a valid value for the target service.
28474 @deffn {Scheme Procedure} service-extension? @var{obj}
28475 Return true if @var{obj} is a service extension.
28478 Occasionally, you might want to simply extend an existing service. This
28479 involves creating a new service type and specifying the extension of
28480 interest, which can be verbose; the @code{simple-service} procedure
28481 provides a shorthand for this.
28483 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
28484 Return a service that extends @var{target} with @var{value}. This works
28485 by creating a singleton service type @var{name}, of which the returned
28486 service is an instance.
28488 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
28492 (simple-service 'my-mcron-job mcron-service-type
28493 #~(job '(next-hour (3)) "guix gc -F 2G"))
28497 At the core of the service abstraction lies the @code{fold-services}
28498 procedure, which is responsible for ``compiling'' a list of services
28499 down to a single directory that contains everything needed to boot and
28500 run the system---the directory shown by the @command{guix system build}
28501 command (@pxref{Invoking guix system}). In essence, it propagates
28502 service extensions down the service graph, updating each node parameters
28503 on the way, until it reaches the root node.
28505 @deffn {Scheme Procedure} fold-services @var{services} @
28506 [#:target-type @var{system-service-type}]
28507 Fold @var{services} by propagating their extensions down to the root of
28508 type @var{target-type}; return the root service adjusted accordingly.
28511 Lastly, the @code{(gnu services)} module also defines several essential
28512 service types, some of which are listed below.
28514 @defvr {Scheme Variable} system-service-type
28515 This is the root of the service graph. It produces the system directory
28516 as returned by the @command{guix system build} command.
28519 @defvr {Scheme Variable} boot-service-type
28520 The type of the ``boot service'', which produces the @dfn{boot script}.
28521 The boot script is what the initial RAM disk runs when booting.
28524 @defvr {Scheme Variable} etc-service-type
28525 The type of the @file{/etc} service. This service is used to create
28526 files under @file{/etc} and can be extended by
28527 passing it name/file tuples such as:
28530 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
28533 In this example, the effect would be to add an @file{/etc/issue} file
28534 pointing to the given file.
28537 @defvr {Scheme Variable} setuid-program-service-type
28538 Type for the ``setuid-program service''. This service collects lists of
28539 executable file names, passed as gexps, and adds them to the set of
28540 setuid-root programs on the system (@pxref{Setuid Programs}).
28543 @defvr {Scheme Variable} profile-service-type
28544 Type of the service that populates the @dfn{system profile}---i.e., the
28545 programs under @file{/run/current-system/profile}. Other services can
28546 extend it by passing it lists of packages to add to the system profile.
28549 @cindex provenance tracking, of the operating system
28550 @defvr {Scheme Variable} provenance-service-type
28551 This is the type of the service that records @dfn{provenance meta-data}
28552 in the system itself. It creates several files under
28553 @file{/run/current-system}:
28557 This is a ``channel file'' that can be passed to @command{guix pull -C}
28558 or @command{guix time-machine -C}, and which describes the channels used
28559 to build the system, if that information was available
28560 (@pxref{Channels}).
28562 @item configuration.scm
28563 This is the file that was passed as the value for this
28564 @code{provenance-service-type} service. By default, @command{guix
28565 system reconfigure} automatically passes the OS configuration file it
28566 received on the command line.
28569 This contains the same information as the two other files but in a
28570 format that is more readily processable.
28573 In general, these two pieces of information (channels and configuration
28574 file) are enough to reproduce the operating system ``from source''.
28577 This information is necessary to rebuild your operating system, but it
28578 is not always sufficient. In particular, @file{configuration.scm}
28579 itself is insufficient if it is not self-contained---if it refers to
28580 external Guile modules or to extra files. If you want
28581 @file{configuration.scm} to be self-contained, we recommend that modules
28582 or files it refers to be part of a channel.
28584 Besides, provenance meta-data is ``silent'' in the sense that it does
28585 not change the bits contained in your system, @emph{except for the
28586 meta-data bits themselves}. Two different OS configurations or sets of
28587 channels can lead to the same system, bit-for-bit; when
28588 @code{provenance-service-type} is used, these two systems will have
28589 different meta-data and thus different store file names, which makes
28590 comparison less trivial.
28593 This service is automatically added to your operating system
28594 configuration when you use @command{guix system reconfigure},
28595 @command{guix system init}, or @command{guix deploy}.
28598 @node Shepherd Services
28599 @subsection Shepherd Services
28601 @cindex shepherd services
28603 @cindex init system
28604 The @code{(gnu services shepherd)} module provides a way to define
28605 services managed by the GNU@tie{}Shepherd, which is the
28606 initialization system---the first process that is started when the
28607 system boots, also known as PID@tie{}1
28608 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
28610 Services in the Shepherd can depend on each other. For instance, the
28611 SSH daemon may need to be started after the syslog daemon has been
28612 started, which in turn can only happen once all the file systems have
28613 been mounted. The simple operating system defined earlier (@pxref{Using
28614 the Configuration System}) results in a service graph like this:
28616 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
28618 You can actually generate such a graph for any operating system
28619 definition using the @command{guix system shepherd-graph} command
28620 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
28622 The @code{%shepherd-root-service} is a service object representing
28623 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
28624 by passing it lists of @code{<shepherd-service>} objects.
28626 @deftp {Data Type} shepherd-service
28627 The data type representing a service managed by the Shepherd.
28630 @item @code{provision}
28631 This is a list of symbols denoting what the service provides.
28633 These are the names that may be passed to @command{herd start},
28634 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
28635 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
28636 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
28638 @item @code{requirement} (default: @code{'()})
28639 List of symbols denoting the Shepherd services this one depends on.
28641 @cindex one-shot services, for the Shepherd
28642 @item @code{one-shot?} (default: @code{#f})
28643 Whether this service is @dfn{one-shot}. One-shot services stop immediately
28644 after their @code{start} action has completed. @xref{Slots of services,,,
28645 shepherd, The GNU Shepherd Manual}, for more info.
28647 @item @code{respawn?} (default: @code{#t})
28648 Whether to restart the service when it stops, for instance when the
28649 underlying process dies.
28652 @itemx @code{stop} (default: @code{#~(const #f)})
28653 The @code{start} and @code{stop} fields refer to the Shepherd's
28654 facilities to start and stop processes (@pxref{Service De- and
28655 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
28656 G-expressions that get expanded in the Shepherd configuration file
28657 (@pxref{G-Expressions}).
28659 @item @code{actions} (default: @code{'()})
28660 @cindex actions, of Shepherd services
28661 This is a list of @code{shepherd-action} objects (see below) defining
28662 @dfn{actions} supported by the service, in addition to the standard
28663 @code{start} and @code{stop} actions. Actions listed here become available as
28664 @command{herd} sub-commands:
28667 herd @var{action} @var{service} [@var{arguments}@dots{}]
28670 @item @code{auto-start?} (default: @code{#t})
28671 Whether this service should be started automatically by the Shepherd. If it
28672 is @code{#f} the service has to be started manually with @code{herd start}.
28674 @item @code{documentation}
28675 A documentation string, as shown when running:
28678 herd doc @var{service-name}
28681 where @var{service-name} is one of the symbols in @code{provision}
28682 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
28684 @item @code{modules} (default: @code{%default-modules})
28685 This is the list of modules that must be in scope when @code{start} and
28686 @code{stop} are evaluated.
28691 @deftp {Data Type} shepherd-action
28692 This is the data type that defines additional actions implemented by a
28693 Shepherd service (see above).
28697 Symbol naming the action.
28699 @item documentation
28700 This is a documentation string for the action. It can be viewed by running:
28703 herd doc @var{service} action @var{action}
28707 This should be a gexp that evaluates to a procedure of at least one argument,
28708 which is the ``running value'' of the service (@pxref{Slots of services,,,
28709 shepherd, The GNU Shepherd Manual}).
28712 The following example defines an action called @code{say-hello} that kindly
28718 (documentation "Say hi!")
28719 (procedure #~(lambda (running . args)
28720 (format #t "Hello, friend! arguments: ~s\n"
28725 Assuming this action is added to the @code{example} service, then you can do:
28728 # herd say-hello example
28729 Hello, friend! arguments: ()
28730 # herd say-hello example a b c
28731 Hello, friend! arguments: ("a" "b" "c")
28734 This, as you can see, is a fairly sophisticated way to say hello.
28735 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
28739 @defvr {Scheme Variable} shepherd-root-service-type
28740 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
28742 This is the service type that extensions target when they want to create
28743 shepherd services (@pxref{Service Types and Services}, for an example).
28744 Each extension must pass a list of @code{<shepherd-service>}.
28747 @defvr {Scheme Variable} %shepherd-root-service
28748 This service represents PID@tie{}1.
28752 @node Documentation
28753 @chapter Documentation
28755 @cindex documentation, searching for
28756 @cindex searching for documentation
28757 @cindex Info, documentation format
28759 @cindex manual pages
28760 In most cases packages installed with Guix come with documentation.
28761 There are two main documentation formats: ``Info'', a browseable
28762 hypertext format used for GNU software, and ``manual pages'' (or ``man
28763 pages''), the linear documentation format traditionally found on Unix.
28764 Info manuals are accessed with the @command{info} command or with Emacs,
28765 and man pages are accessed using @command{man}.
28767 You can look for documentation of software installed on your system by
28768 keyword. For example, the following command searches for information
28769 about ``TLS'' in Info manuals:
28773 "(emacs)Network Security" -- STARTTLS
28774 "(emacs)Network Security" -- TLS
28775 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
28776 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
28781 The command below searches for the same keyword in man pages:
28785 SSL (7) - OpenSSL SSL/TLS library
28786 certtool (1) - GnuTLS certificate tool
28790 These searches are purely local to your computer so you have the
28791 guarantee that documentation you find corresponds to what you have
28792 actually installed, you can access it off-line, and your privacy is
28795 Once you have these results, you can view the relevant documentation by
28799 $ info "(gnutls)Core TLS API"
28809 Info manuals contain sections and indices as well as hyperlinks like
28810 those found in Web pages. The @command{info} reader (@pxref{Top, Info
28811 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
28812 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
28813 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
28814 Introduction}, for an introduction to Info navigation.
28816 @node Installing Debugging Files
28817 @chapter Installing Debugging Files
28819 @cindex debugging files
28820 Program binaries, as produced by the GCC compilers for instance, are
28821 typically written in the ELF format, with a section containing
28822 @dfn{debugging information}. Debugging information is what allows the
28823 debugger, GDB, to map binary code to source code; it is required to
28824 debug a compiled program in good conditions.
28826 The problem with debugging information is that is takes up a fair amount
28827 of disk space. For example, debugging information for the GNU C Library
28828 weighs in at more than 60 MiB. Thus, as a user, keeping all the
28829 debugging info of all the installed programs is usually not an option.
28830 Yet, space savings should not come at the cost of an impediment to
28831 debugging---especially in the GNU system, which should make it easier
28832 for users to exert their computing freedom (@pxref{GNU Distribution}).
28834 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
28835 mechanism that allows users to get the best of both worlds: debugging
28836 information can be stripped from the binaries and stored in separate
28837 files. GDB is then able to load debugging information from those files,
28838 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
28841 The GNU distribution takes advantage of this by storing debugging
28842 information in the @code{lib/debug} sub-directory of a separate package
28843 output unimaginatively called @code{debug} (@pxref{Packages with
28844 Multiple Outputs}). Users can choose to install the @code{debug} output
28845 of a package when they need it. For instance, the following command
28846 installs the debugging information for the GNU C Library and for GNU
28850 guix install glibc:debug guile:debug
28853 GDB must then be told to look for debug files in the user's profile, by
28854 setting the @code{debug-file-directory} variable (consider setting it
28855 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
28859 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
28862 From there on, GDB will pick up debugging information from the
28863 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
28865 In addition, you will most likely want GDB to be able to show the source
28866 code being debugged. To do that, you will have to unpack the source
28867 code of the package of interest (obtained with @code{guix build
28868 --source}, @pxref{Invoking guix build}), and to point GDB to that source
28869 directory using the @code{directory} command (@pxref{Source Path,
28870 @code{directory},, gdb, Debugging with GDB}).
28872 @c XXX: keep me up-to-date
28873 The @code{debug} output mechanism in Guix is implemented by the
28874 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
28875 opt-in---debugging information is available only for the packages
28876 with definitions explicitly declaring a @code{debug} output. This may be
28877 changed to opt-out in the future if our build farm servers can handle
28878 the load. To check whether a package has a @code{debug} output, use
28879 @command{guix package --list-available} (@pxref{Invoking guix package}).
28882 @node Security Updates
28883 @chapter Security Updates
28885 @cindex security updates
28886 @cindex security vulnerabilities
28887 Occasionally, important security vulnerabilities are discovered in software
28888 packages and must be patched. Guix developers try hard to keep track of
28889 known vulnerabilities and to apply fixes as soon as possible in the
28890 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
28891 containing only security updates). The @command{guix lint} tool helps
28892 developers find out about vulnerable versions of software packages in the
28897 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
28898 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
28899 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
28903 @xref{Invoking guix lint}, for more information.
28905 Guix follows a functional
28906 package management discipline (@pxref{Introduction}), which implies
28907 that, when a package is changed, @emph{every package that depends on it}
28908 must be rebuilt. This can significantly slow down the deployment of
28909 fixes in core packages such as libc or Bash, since basically the whole
28910 distribution would need to be rebuilt. Using pre-built binaries helps
28911 (@pxref{Substitutes}), but deployment may still take more time than
28915 To address this, Guix implements @dfn{grafts}, a mechanism that allows
28916 for fast deployment of critical updates without the costs associated
28917 with a whole-distribution rebuild. The idea is to rebuild only the
28918 package that needs to be patched, and then to ``graft'' it onto packages
28919 explicitly installed by the user and that were previously referring to
28920 the original package. The cost of grafting is typically very low, and
28921 order of magnitudes lower than a full rebuild of the dependency chain.
28923 @cindex replacements of packages, for grafts
28924 For instance, suppose a security update needs to be applied to Bash.
28925 Guix developers will provide a package definition for the ``fixed''
28926 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
28927 Packages}). Then, the original package definition is augmented with a
28928 @code{replacement} field pointing to the package containing the bug fix:
28935 (replacement bash-fixed)))
28938 From there on, any package depending directly or indirectly on Bash---as
28939 reported by @command{guix gc --requisites} (@pxref{Invoking guix
28940 gc})---that is installed is automatically ``rewritten'' to refer to
28941 @code{bash-fixed} instead of @code{bash}. This grafting process takes
28942 time proportional to the size of the package, usually less than a
28943 minute for an ``average'' package on a recent machine. Grafting is
28944 recursive: when an indirect dependency requires grafting, then grafting
28945 ``propagates'' up to the package that the user is installing.
28947 Currently, the length of the name and version of the graft and that of
28948 the package it replaces (@code{bash-fixed} and @code{bash} in the example
28949 above) must be equal. This restriction mostly comes from the fact that
28950 grafting works by patching files, including binary files, directly.
28951 Other restrictions may apply: for instance, when adding a graft to a
28952 package providing a shared library, the original shared library and its
28953 replacement must have the same @code{SONAME} and be binary-compatible.
28955 The @option{--no-grafts} command-line option allows you to forcefully
28956 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
28960 guix build bash --no-grafts
28964 returns the store file name of the original Bash, whereas:
28971 returns the store file name of the ``fixed'', replacement Bash. This
28972 allows you to distinguish between the two variants of Bash.
28974 To verify which Bash your whole profile refers to, you can run
28975 (@pxref{Invoking guix gc}):
28978 guix gc -R `readlink -f ~/.guix-profile` | grep bash
28982 @dots{} and compare the store file names that you get with those above.
28983 Likewise for a complete Guix system generation:
28986 guix gc -R `guix system build my-config.scm` | grep bash
28989 Lastly, to check which Bash running processes are using, you can use the
28990 @command{lsof} command:
28993 lsof | grep /gnu/store/.*bash
28997 @node Bootstrapping
28998 @chapter Bootstrapping
29000 @c Adapted from the ELS 2013 paper.
29002 @cindex bootstrapping
29004 Bootstrapping in our context refers to how the distribution gets built
29005 ``from nothing''. Remember that the build environment of a derivation
29006 contains nothing but its declared inputs (@pxref{Introduction}). So
29007 there's an obvious chicken-and-egg problem: how does the first package
29008 get built? How does the first compiler get compiled? Note that this is
29009 a question of interest only to the curious hacker, not to the regular
29010 user, so you can shamelessly skip this section if you consider yourself
29011 a ``regular user''.
29013 @cindex bootstrap binaries
29014 The GNU system is primarily made of C code, with libc at its core. The
29015 GNU build system itself assumes the availability of a Bourne shell and
29016 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
29017 `grep'. Furthermore, build programs---programs that run
29018 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
29019 (@pxref{Derivations}). Consequently, to be able to build anything at
29020 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
29021 Binutils, libc, and the other packages mentioned above---the
29022 @dfn{bootstrap binaries}.
29024 These bootstrap binaries are ``taken for granted'', though we can also
29025 re-create them if needed (@pxref{Preparing to Use the Bootstrap
29029 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
29030 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
29033 @node Reduced Binary Seed Bootstrap
29034 @section The Reduced Binary Seed Bootstrap
29036 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
29037 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
29038 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
29039 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
29040 ``taken for granted.''
29042 Taking the bootstrap binaries for granted means that we consider them to
29043 be a correct and trustworthy ``seed'' for building the complete system.
29044 Therein lies a problem: the combined size of these bootstrap binaries is
29045 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
29046 or even inspecting these is next to impossible.
29048 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
29049 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
29050 Source Bootstrap'' and while we are working towards that goal it would
29051 be hyperbole to use that term for what we do now.}.
29053 The Reduced Binary Seed bootstrap removes the most critical tools---from a
29054 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
29055 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
29056 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
29057 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
29059 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
29060 C Library are built from source. From here on the more traditional
29061 bootstrap process resumes. This approach has reduced the bootstrap
29062 binaries in size to about 145MB in Guix v1.1.
29064 The next step that Guix has taken is to replace the shell and all its
29065 utilities with implementations in Guile Scheme, the @emph{Scheme-only
29066 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
29067 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
29068 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
29069 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
29070 removed are now built from source.
29072 Building the GNU System from source is currently only possibly by adding
29073 some historical GNU packages as intermediate steps@footnote{Packages
29074 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
29075 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
29076 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
29077 and GNU packages become more bootstrappable again (e.g., new releases of
29078 GNU Sed will also ship as gzipped tarballs again, as alternative to the
29079 hard to bootstrap @code{xz}-compression), this set of added packages can
29080 hopefully be reduced again.
29082 The graph below shows the resulting dependency graph for
29083 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
29084 traditional bootstrap of the rest of the Guix System.
29086 @c ./pre-inst-env guix graph -e '(@@ (gnu packages commencement) gcc-core-mesboot0)' | sed -re 's,((bootstrap-mescc-tools|bootstrap-mes|guile-bootstrap).*shape =) box,\1 ellipse,' > doc/images/gcc-core-mesboot0-graph.dot
29087 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
29089 The only significant binary bootstrap seeds that remain@footnote{
29090 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
29091 together with @code{mes}.} are a Scheme intepreter and a Scheme
29092 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
29093 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
29094 to get Guile running.}.
29096 This further reduction has brought down the size of the binary seed to
29097 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
29099 Work is ongoing to remove all binary blobs from our free software
29100 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
29101 is work to bring these bootstraps to the @code{arm-linux} and
29102 @code{aarch64-linux} architectures and to the Hurd.
29104 If you are interested, join us on @samp{#bootstrappable} on the Freenode
29105 IRC network or discuss on @email{bug-mes@@gnu.org} or
29106 @email{gash-devel@@nongnu.org}.
29108 @node Preparing to Use the Bootstrap Binaries
29109 @section Preparing to Use the Bootstrap Binaries
29111 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
29112 @c large image, it's hard to scroll. Oh well.
29113 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
29115 The figure above shows the very beginning of the dependency graph of the
29116 distribution, corresponding to the package definitions of the @code{(gnu
29117 packages bootstrap)} module. A similar figure can be generated with
29118 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
29121 guix graph -t derivation \
29122 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
29123 | dot -Tps > gcc.ps
29126 or, for the further Reduced Binary Seed bootstrap
29129 guix graph -t derivation \
29130 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
29131 | dot -Tps > mes.ps
29134 At this level of detail, things are
29135 slightly complex. First, Guile itself consists of an ELF executable,
29136 along with many source and compiled Scheme files that are dynamically
29137 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
29138 tarball shown in this graph. This tarball is part of Guix's ``source''
29139 distribution, and gets inserted into the store with @code{add-to-store}
29140 (@pxref{The Store}).
29142 But how do we write a derivation that unpacks this tarball and adds it
29143 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
29144 derivation---the first one that gets built---uses @code{bash} as its
29145 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
29146 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
29147 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
29148 the Guix source distribution, whose sole purpose is to allow the Guile
29149 tarball to be unpacked.
29151 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
29152 Guile that can be used to run subsequent build programs. Its first task
29153 is to download tarballs containing the other pre-built binaries---this
29154 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
29155 @code{ftp-client.scm} are used for this purpose. The
29156 @code{module-import.drv} derivations import those modules in a directory
29157 in the store, using the original layout. The
29158 @code{module-import-compiled.drv} derivations compile those modules, and
29159 write them in an output directory with the right layout. This
29160 corresponds to the @code{#:modules} argument of
29161 @code{build-expression->derivation} (@pxref{Derivations}).
29163 Finally, the various tarballs are unpacked by the derivations
29164 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
29165 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
29166 point we have a working C tool chain.
29168 @unnumberedsec Building the Build Tools
29170 Bootstrapping is complete when we have a full tool chain that does not
29171 depend on the pre-built bootstrap tools discussed above. This
29172 no-dependency requirement is verified by checking whether the files of
29173 the final tool chain contain references to the @file{/gnu/store}
29174 directories of the bootstrap inputs. The process that leads to this
29175 ``final'' tool chain is described by the package definitions found in
29176 the @code{(gnu packages commencement)} module.
29178 The @command{guix graph} command allows us to ``zoom out'' compared to
29179 the graph above, by looking at the level of package objects instead of
29180 individual derivations---remember that a package may translate to
29181 several derivations, typically one derivation to download its source,
29182 one to build the Guile modules it needs, and one to actually build the
29183 package from source. The command:
29186 guix graph -t bag \
29187 -e '(@@@@ (gnu packages commencement)
29188 glibc-final-with-bootstrap-bash)' | xdot -
29192 displays the dependency graph leading to the ``final'' C
29193 library@footnote{You may notice the @code{glibc-intermediate} label,
29194 suggesting that it is not @emph{quite} final, but as a good
29195 approximation, we will consider it final.}, depicted below.
29197 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
29199 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
29200 The first tool that gets built with the bootstrap binaries is
29201 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
29202 for all the following packages. From there Findutils and Diffutils get
29205 Then come the first-stage Binutils and GCC, built as pseudo cross
29206 tools---i.e., with @option{--target} equal to @option{--host}. They are
29207 used to build libc. Thanks to this cross-build trick, this libc is
29208 guaranteed not to hold any reference to the initial tool chain.
29210 From there the final Binutils and GCC (not shown above) are built. GCC
29211 uses @command{ld} from the final Binutils, and links programs against
29212 the just-built libc. This tool chain is used to build the other
29213 packages used by Guix and by the GNU Build System: Guile, Bash,
29216 And voilà! At this point we have the complete set of build tools that
29217 the GNU Build System expects. These are in the @code{%final-inputs}
29218 variable of the @code{(gnu packages commencement)} module, and are
29219 implicitly used by any package that uses @code{gnu-build-system}
29220 (@pxref{Build Systems, @code{gnu-build-system}}).
29223 @unnumberedsec Building the Bootstrap Binaries
29225 @cindex bootstrap binaries
29226 Because the final tool chain does not depend on the bootstrap binaries,
29227 those rarely need to be updated. Nevertheless, it is useful to have an
29228 automated way to produce them, should an update occur, and this is what
29229 the @code{(gnu packages make-bootstrap)} module provides.
29231 The following command builds the tarballs containing the bootstrap binaries
29232 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
29233 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
29234 and Guile, and a tarball containing a mixture of Coreutils and other basic
29235 command-line tools):
29238 guix build bootstrap-tarballs
29241 The generated tarballs are those that should be referred to in the
29242 @code{(gnu packages bootstrap)} module mentioned at the beginning of
29245 Still here? Then perhaps by now you've started to wonder: when do we
29246 reach a fixed point? That is an interesting question! The answer is
29247 unknown, but if you would like to investigate further (and have
29248 significant computational and storage resources to do so), then let us
29251 @unnumberedsec Reducing the Set of Bootstrap Binaries
29253 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
29254 binary code! Why is that a problem? It's a problem because these big chunks
29255 of binary code are practically non-auditable, which makes it hard to establish
29256 what source code produced them. Every unauditable binary also leaves us
29257 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
29258 paper @emph{Reflections on Trusting Trust}.
29260 This is mitigated by the fact that our bootstrap binaries were generated
29261 from an earlier Guix revision. Nevertheless it lacks the level of
29262 transparency that we get in the rest of the package dependency graph,
29263 where Guix always gives us a source-to-binary mapping. Thus, our goal
29264 is to reduce the set of bootstrap binaries to the bare minimum.
29266 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
29267 on-going projects to do that. One of these is about replacing the
29268 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
29269 of increasing complexity, which could be built from source starting from
29270 a simple and auditable assembler.
29272 Our first major achievement is the replacement of of GCC, the GNU C Library
29273 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
29274 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
29275 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
29276 bootstrapped yet and thus we inject them as binary seeds. We call this the
29277 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
29278 binaries! Also, it has eliminated the C compiler binary; i686-linux and
29279 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
29281 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
29282 also looking at any other bootstrap binaries. Your help is welcome!
29285 @chapter Porting to a New Platform
29287 As discussed above, the GNU distribution is self-contained, and
29288 self-containment is achieved by relying on pre-built ``bootstrap
29289 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
29290 operating system kernel, CPU architecture, and application binary
29291 interface (ABI). Thus, to port the distribution to a platform that is
29292 not yet supported, one must build those bootstrap binaries, and update
29293 the @code{(gnu packages bootstrap)} module to use them on that platform.
29295 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
29296 When everything goes well, and assuming the GNU tool chain supports the
29297 target platform, this can be as simple as running a command like this
29301 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
29304 For this to work, the @code{glibc-dynamic-linker} procedure in
29305 @code{(gnu packages bootstrap)} must be augmented to return the right
29306 file name for libc's dynamic linker on that platform; likewise,
29307 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
29308 taught about the new platform.
29310 Once these are built, the @code{(gnu packages bootstrap)} module needs
29311 to be updated to refer to these binaries on the target platform. That
29312 is, the hashes and URLs of the bootstrap tarballs for the new platform
29313 must be added alongside those of the currently supported platforms. The
29314 bootstrap Guile tarball is treated specially: it is expected to be
29315 available locally, and @file{gnu/local.mk} has rules to download it for
29316 the supported architectures; a rule for the new platform must be added
29319 In practice, there may be some complications. First, it may be that the
29320 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
29321 above) is not recognized by all the GNU tools. Typically, glibc
29322 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
29323 configure flag (see @code{gcc.scm} for examples of how to handle this).
29324 Second, some of the required packages could fail to build for that
29325 platform. Lastly, the generated binaries could be broken for some
29328 @c *********************************************************************
29329 @include contributing.texi
29331 @c *********************************************************************
29332 @node Acknowledgments
29333 @chapter Acknowledgments
29335 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
29336 which was designed and
29337 implemented by Eelco Dolstra, with contributions from other people (see
29338 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
29339 management, and promoted unprecedented features, such as transactional
29340 package upgrades and rollbacks, per-user profiles, and referentially
29341 transparent build processes. Without this work, Guix would not exist.
29343 The Nix-based software distributions, Nixpkgs and NixOS, have also been
29344 an inspiration for Guix.
29346 GNU@tie{}Guix itself is a collective work with contributions from a
29347 number of people. See the @file{AUTHORS} file in Guix for more
29348 information on these fine people. The @file{THANKS} file lists people
29349 who have helped by reporting bugs, taking care of the infrastructure,
29350 providing artwork and themes, making suggestions, and more---thank you!
29353 @c *********************************************************************
29354 @node GNU Free Documentation License
29355 @appendix GNU Free Documentation License
29356 @cindex license, GNU Free Documentation License
29357 @include fdl-1.3.texi
29359 @c *********************************************************************
29360 @node Concept Index
29361 @unnumbered Concept Index
29364 @node Programming Index
29365 @unnumbered Programming Index
29366 @syncodeindex tp fn
29367 @syncodeindex vr fn
29372 @c Local Variables:
29373 @c ispell-local-dictionary: "american";